Sample records for arc furnace steel

  1. Methods of steel manufacturing - The electric arc furnace

    NASA Astrophysics Data System (ADS)

    Dragna, E. C.; Ioana, A.; Constantin, N.

    2018-01-01

    Initially, the carbon content was reduced by mixing “the iron” with metallic ingots in ceramic crucibles/melting pots, with external heat input. As time went by the puddling procedure was developed, a procedure which also assumes a mixture with oxidized iron ore. In 1856 Bessemer invented the convertor, thus demonstrating that steel can be obtained following the transition of an air stream through the liquid pig iron. The invention of Thomas, a slightly modified basic-lined converter, fostered the desulphurization of the steel and the removal of the phosphate from it. During the same period, in 1865, in Sireuil, the Frenchman Martin applies Siemens’ heat regeneration invention and brings into service the furnace with a charge composed of iron pig, scrap iron and iron ore, that produces a high quality steel [1]. An act worthy of being highlighted within the scope of steelmaking is the start-up of the converter with oxygen injection at the upper side, as there are converters that can produce 400 tons of steel in approximately 50 minutes. Currently, the share of the steel produced in electric arc furnaces with a charge composed of scrap iron has increased. Due to this aspect, the electric arc furnace was able to impose itself on the market.

  2. Characterization of Sintering Dust, Blast Furnace Dust and Carbon Steel Electric Arc Furnace Dust

    NASA Astrophysics Data System (ADS)

    Chang, Feng; Wu, Shengli; Zhang, Fengjie; Lu, Hua; Du, Kaiping

    In order to make a complete understanding of steel plant metallurgical dusts and to realize the goal of zero-waste, a study of their properties was undertaken. For these purposes, samples of two sintering dusts (SD), two blast furnace dusts (BFD), and one electric arc furnace dust (EAFD) taken from the regular production process were subjected to a series of tests. The tests were carried out by using granulometry analysis, chemical analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy via SEM (EDS), and Fourier transform infrared spectroscopy (FTIR). The dominant elements having an advantage of reuse are Fe, K, Cl, Zn, C. The dominant mineralogical phases identified in sintering dust are KCl, Fe2O3, CaCO3, CaMg(CO3)2, NaCl, SiO2. Mineralogical phases exist in blast furnace dust are Fe2O3, Fe3O4, with small amount of KCl and kaolinite coexist. While in electric arc furnace dust, Fe3O4, ZnFe2O4, CaCO3, CaO, Ca(OH)2 are detected.

  3. Rational position of a plasmatron and energy saving in a plasma-arc steel-melting furnace

    NASA Astrophysics Data System (ADS)

    Makarov, A. N.; Zuikov, R. M.; Lugovoi, Yu. A.

    2009-12-01

    The rational position of a plasmatron in a plasma-arc steel-melting furnace is studied analytically. The rational position by the end of melting of a charge and after its melting is found to be the position of a plasmatron at an angle of 70 °-75 ° to the vertical axis. As compared to the roof position of the plasmatron, this position increases arc radiation onto the metal pool and the arc efficiency increases by 40-60%.

  4. Skid resistance performance of asphalt wearing courses with electric arc furnace slag aggregates.

    PubMed

    Kehagia, Fotini

    2009-05-01

    Metallurgical slags are by-products of the iron and steel industry and are subdivided into blast furnace slag and steel slag according to the different steel-producing processes. In Greece, slags are mostly produced from steelmaking using the electric arc furnace process, and subsequently are either disposed in a random way or utilized by the cement industry. Steel slag has been recently used, worldwide, as hard aggregates in wearing courses in order to improve the skidding resistance of asphalt pavements. At the Highway Laboratory, Department of Civil Engineering of Aristotle University of Thessaloniki research has been carried out in the field of steel slags, and especially in electric arc furnace (EAF) slag, to evaluate their possible use in highway engineering. In this paper, the recent results of anti-skidding performance of steel slag aggregates in highway pavements are presented.

  5. Elements of the electric arc furnace's environmental management

    NASA Astrophysics Data System (ADS)

    Ioana, Adrian; Semenescu, Augustin; Costoiu, Mihnea; Marcu, Dragoş

    2017-12-01

    The paper presents a theoretical and experimental analysis of the polluting generating mechanisms for steel making in the Electric Arc Furnaces (EAF). The scheme for the environment's polluting system through the EAF is designed and presented in this paper. The ecological experimenting consisted of determining by specialized measures of the dust percentage in the evacuated gases from the EAF and of thereof gas pollutants. From the point of view of reducing the impact on the environment, the main problem of the electric arc furnace (EAF) is the optimization of the powder collecting from the process gases, both from the furnace and from the work-area. The paper deals with the best dependence between the aggregate's constructive, functional and technological factors, which are necessary for the furnace's ecologization and for its energetically-technologically performances increasing.

  6. Optical emission from a small scale model electric arc furnace in 250-600 nm region.

    PubMed

    Mäkinen, A; Niskanen, J; Tikkala, H; Aksela, H

    2013-04-01

    Optical emission spectroscopy has been for long proposed for monitoring and studying industrial steel making processes. Whereas the radiative decay of thermal excitations is always taking place in high temperatures needed in steel production, one of the most promising environment for such studies are electric arc furnaces, creating plasma in excited electronic states that relax with intense characteristic emission in the optical regime. Unfortunately, large industrial scale electric arc furnaces also present a challenging environment for optical emission studies and application of the method is not straightforward. To study the usability of optical emission spectroscopy in real electric arc furnaces, we have developed a laboratory scale DC electric arc furnace presented in this paper. With the setup, optical emission spectra of Fe, Cr, Cr2O3, Ni, SiO2, Al2O3, CaO, and MgO were recorded in the wavelength range 250-600 nm and the results were analyzed with the help of reference data. The work demonstrates that using characteristic optical emission, obtaining in situ chemical information from oscillating plasma of electric arc furnaces is indeed possible. In spite of complications, the method could possibly be applied to industrial scale steel making process in order to improve its efficiency.

  7. Heavy metal recovery from electric arc furnace steel slag by using hydrochloric acid leaching

    NASA Astrophysics Data System (ADS)

    Wei, Lim Jin; Haan, Ong Teng; Shean Yaw, Thomas Choong; Chuah Abdullah, Luqman; Razak, Mus'ab Abdul; Cionita, Tezara; Toudehdehghan, Abdolreza

    2018-03-01

    Electric Arc Furnace steel slag (EAFS) is the waste produced in steelmaking industry. Environmental problem such as pollution will occur when dumping the steel slag waste into the landfill. These steel slags have properties that are suitable for various applications such as water treatment and wastewater. The objective of this study is to develop efficient and economical chlorination route for EAFS extraction by using leaching process. Various parameters such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature are investigated to determine the optimum conditions. As a result, the dissolution rate can be determined by changing the parameters, such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature. The optimum conditions for dissolution rates for the leaching process is at 3.0 M hydrochloric acid, particle size of 1.18 mm, reaction time of 2.5 hour and the temperature of 90°C.

  8. Power quality analysis of DC arc furnace operation using the Bowman model for electric arc

    NASA Astrophysics Data System (ADS)

    Gherman, P. L.

    2018-01-01

    This work is about a relatively new domain. The DC electric arc is superior to the AC electric arc and it’s not used in Romania. This is why we analyzed the work functions of these furnaces by simulation and model checking of the simulation results.The conclusions are favorable, to be carried is to develop a real-time control system of steel elaboration process.

  9. The influence of the structure of the metal load removal from liquid steel in electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Pǎcurar, Cristina; Hepuť, Teodor; Crisan, Eugen

    2016-06-01

    One of the main technical and economic indicators in the steel industry and steel respectively the development it is the removal of liquid steel. This indicator depends on several factors, namely technology: the structure and the quality metal load, the degree of preparedness of it, and the content of non-metallic material accompanying the unit of drawing up, the technology for the elaboration, etc. research has been taken into account in drawing up steel electric arc furnace type spring EBT (Electric Bottom taping), seeking to load and removing components of liquid steel. Metal load has been composed of eight metal grades, in some cases with great differences in terms of quality. Data obtained were processed in the EXCEL spreadsheet programs and MATLAB, the results obtained being presented both graphically and analytically. On the basis of the results obtained may opt for a load optimal structure metal.

  10. Calculation of gas release from DC and AC arc furnaces in a foundry

    NASA Astrophysics Data System (ADS)

    Krutyanskii, M. M.; Nekhamin, S. M.; Rebikov, E. M.

    2016-12-01

    A procedure for the calculation of gas release from arc furnaces is presented. The procedure is based on the stoichiometric ratios of the oxidation of carbon in liquid iron during the oxidation heat period and the oxidation of iron from a steel charge by oxygen in the period of solid charge melting during the gas exchange of the furnace cavity with the external atmosphere.

  11. Heat-electrical regeneration way to intensive energy saving in an electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Kartavtcev, S.; Matveev, S.; Neshporenko, E.

    2018-03-01

    Energy saving in steel production is of great significance for its large economical scale of 1500 mil t/year and high-energy consumption. Steady trend of last years is an increase of steel production in electric arc furnaces (EAF) with a very high consumption of electricity up to 750 kWh/ton. The intention to reduce so much energy consumption they can reach by many ways. One of such way is a transforming heat energy of liquid steel to electricity and destine it to steel electric arc process. Under certain conditions, it may lead to “zero” consumption of electric power in the process. The development of these conditions leads to the formation of energy-efficient heat schemes, with a minimum electricity consumption from the external network.

  12. OPTIMAL OPERATION OF ELECTRIC ARC FURNACES (EAF) TO MINIMIZE THE GENERATION OF AIR POLLUTANTS AT THE SOURCE

    EPA Science Inventory

    The manufacture of steel by electric arc furnaces (EAF) is continuing to increase in usage in the United States with current production estimated to be over 63 million tons per year. The reduction of emissions from steel producers has been slow for two main reasons: the nee...

  13. Phosphorus removal by electric arc furnace steel slag adsorption

    NASA Astrophysics Data System (ADS)

    Lim, J. W.; Lee, K. F.; Chong, Thomas S. Y.; Abdullah, L. C.; Razak, M. A.; Tezara, C.

    2017-10-01

    As to overcome the eutrophication in lakes and reservoirs which is resulted from excessive input of phosphorus due to rapid urbanization or uncontrolled agricultural activities, Electric Arc Furnace steel slag (EAFS), a steelmaking by-product, in which the disposal of this industrial waste considered economically unfavourable yet it’s physical and chemical properties exhibits high potential to be great P adsorbent. The objective of this study was to identify most suitable mathematical model in description of adsorption by using traditional batch experiment and to investigate the effect on Phosphorus removal efficiency and Phosphorus removal capacity by EAFS adsorption through variation of parameters such as pH, size of slag and initial concentration of Phosphorus. Result demonstrated that, Langmuir is suitable in describing Phosphorus removal mechanisms with the Maximum Adsorption Capacity, Q m of 0.166 mg/g and Langmuir Constant, KL of 0.03519 L/mg. As for effect studies, smaller size of adsorbent shows higher percentage (up to 37.8%) of Phosphorus removal compared to the larger size. Besides that, the experiment indicated a more acidic environment is favourable for Phosphorus removal and the amount of Phosphorus adsorbed at pH 3.0 was the highest. In addition, the adsorption capacity increases steadily as the initial Phosphorus concentration increases but it remained steady at 100mg P/L. Eventually, this study serves as better understanding on preliminary studies of P removal mechanisms by EAFS.

  14. Experimental evaluation of high performance base course and road base asphalt concrete with electric arc furnace steel slags.

    PubMed

    Pasetto, Marco; Baldo, Nicola

    2010-09-15

    The paper presents the results of a laboratory study aimed at verifying the use of two types of electric arc furnace (EAF) steel slags as substitutes for natural aggregates, in the composition of base course and road base asphalt concrete (BBAC) for flexible pavements. The trial was composed of a preliminary study of the chemical, physical, mechanical and leaching properties of the EAF steel slags, followed by the mix design and performance characterization of the bituminous mixes, through gyratory compaction tests, permanent deformation tests, stiffness modulus tests at various temperatures, fatigue tests and indirect tensile strength tests. All the mixtures with EAF slags presented better mechanical characteristics than those of the corresponding asphalts with natural aggregate and satisfied the requisites for acceptance in the Italian road sector technical standards, thus resulting as suitable for use in road construction. Copyright 2010 Elsevier B.V. All rights reserved.

  15. Computational Modeling of Arc-Slag Interaction in DC Furnaces

    NASA Astrophysics Data System (ADS)

    Reynolds, Quinn G.

    2017-02-01

    The plasma arc is central to the operation of the direct-current arc furnace, a unit operation commonly used in high-temperature processing of both primary ores and recycled metals. The arc is a high-velocity, high-temperature jet of ionized gas created and sustained by interactions among the thermal, momentum, and electromagnetic fields resulting from the passage of electric current. In addition to being the primary source of thermal energy, the arc jet also couples mechanically with the bath of molten process material within the furnace, causing substantial splashing and stirring in the region in which it impinges. The arc's interaction with the molten bath inside the furnace is studied through use of a multiphase, multiphysics computational magnetohydrodynamic model developed in the OpenFOAM® framework. Results from the computational solver are compared with empirical correlations that account for arc-slag interaction effects.

  16. Upgrading constructed wetlands phosphorus reduction from a dairy effluent using electric arc furnace steel slag filters.

    PubMed

    Weber, D; Drizo, A; Twohig, E; Bird, S; Ross, D

    2007-01-01

    In 2003, a subsurface flow constructed wetlands (SSF-CW) system was built at the University of Vermont (UVM) Paul Miller Dairy Farm as an alternative nutrient management approach for treating barnyard runoff and milk parlour waste. Given the increasing problem of phosphorus (P) pollution in the Lake Champlain region, a slag based P-removal filter technology (PFT) was established (2004) at the CW with two objectives: (i) to test the filters' efficiency as an upgrade unit for improving P removal performance via SSF-CW (ii) to investigate the capacity of filters technology to remove P as a "stand alone" unit. Six individual filters (F1-F6) were filled with electric arc furnace (EAF) steel slag, each containing 112.5 kg of material with a pore volume of 21 L. F1-F4, fed with CW treated water, received approximately 2.17 g DRP kg(-1) EAF steel slag (0.25 kg DRP total) during the 259 day feeding period. F1-F4 retained 1.7 g DRP kg(-1) EAF steel slag, resulting in an average P removal efficiency of 75%. The addition of filters improved CW DRP removal efficiency by 74%. F5 and F6, fed non-treated water, received 1.9 g DRP kg(-1) EAF steel slag (0.22 kg DRP in total) and retained 1.5 g DRP kg(-1) resulting in a P removal efficiency of 72%. The establishment of the EAF slag based PFT is the first in-field evaluation of this technology to reduce P from dairy farm effluent in Vermont.

  17. Laboratory arc furnace features interchangeable hearths

    NASA Technical Reports Server (NTRS)

    Armstrong, J. L.; Kruger, O. L.

    1967-01-01

    Laboratory arc furnace using rapidly interchangeable hearths gains considerable versatility in casting so that buttons or special shaped castings can be produced. It features a sight glass for observation.

  18. Thermodynamic modelling of the formation of zinc-manganese ferrite spinel in electric arc furnace dust.

    PubMed

    Pickles, C A

    2010-07-15

    Electric arc furnace dust is generated when automobile scrap, containing galvanized steel, is remelted in an electric arc furnace. This dust is considered as a hazardous waste in most countries. Zinc is a major component of the dust and can be of significant commercial value. Typically, the majority of the zinc exists as zinc oxide (ZnO) and as a zinc-manganese ferrite spinel ((Zn(x)Mn(y)Fe(1-x-y))Fe(2)O(4)). The recovery of the zinc from the dust in metal recycling and recovery processes, particularly in the hydrometallurgical extraction processes, is often hindered by the presence of the mixed ferrite spinel. However, there is a paucity of information available in the literature on the formation of this spinel. Therefore, in the present research, the equilibrium module of HSC Chemistry 6.1 was utilized to investigate the thermodynamics of the formation of the spinel and the effect of variables on the amount and the composition of the mixed ferrite spinel. It is proposed that the mixed ferrite spinel forms due to the reaction of iron-manganese particulates with both gaseous oxygen and zinc, at the high temperatures in the freeboard of the furnace above the steel melt. Based on the thermodynamic predictions, methods are proposed for minimizing the formation of the mixed ferrite spinel. 2010 Elsevier B.V. All rights reserved.

  19. Behavior of an indigenously fabricated transferred arc plasma furnace for smelting studies

    NASA Astrophysics Data System (ADS)

    A, K. MANDAL; R, K. DISHWAR; O, P. SINHA

    2018-03-01

    The utilization of industrial solid waste for metal recovery requires high-temperature tools due to the presence of silica and alumina, which is reducible at high temperature. In a plasma arc furnace, transferred arc plasma furnace (TAP) can meet all requirements, but the disadvantage of this technology is the high cost. For performing experiments in the laboratory, the TAP was fabricated indigenously in a laboratory based on the different inputs provided in the literature for the furnace design and fabrication. The observed parameters such as arc length, energy consumption, graphite electrode consumption, noise level as well as lining erosion were characterized for this fabricated furnace. The nitrogen plasma increased by around 200 K (200 °C) melt temperature and noise levels decreased by ∼10 dB compared to a normal arc. Hydrogen plasma offered 100 K (100 °C) higher melt temperature with ∼5 dB higher sound level than nitrogen plasma. Nitrogen plasma arc melting showed lower electrode and energy consumption than normal arc melting, whereas hydrogen plasma showed lower energy consumption and higher electrode consumption in comparison to nitrogen plasma. The higher plasma arc temperature resulted in a shorter meltdown time than normal arc with smoother arcing. Hydrogen plasma permitted more heats, reduced meltdown time, and lower energy consumption, but with increased graphite consumption and crucible wear. The present study showed that the fabricated arc plasma is better than the normal arc furnace with respect to temperature generation, energy consumption, and environmental friendliness. Therefore, it could be used effectively for smelting-reduction studies.

  20. Environmental impacts of asphalt mixes with electric arc furnace steel slag.

    PubMed

    Milačič, Radmila; Zuliani, Tea; Oblak, Tina; Mladenovič, Ana; Ančar, Janez Šč

    2011-01-01

    Electric arc furnace (EAF) steel slag can be used as an alternative high-quality material in road construction. Although asphalts with slag aggregates have been recognized as environmentally acceptable, there is a lack of data concerning the potential leaching of toxic Cr(VI) due to the highly alkaline media of EAF slag. Leaching of selected water extractable metals from slag indicated elevated concentrations of total chromium and Cr(VI). To estimate the environmental impacts of asphalt mixes with slag, leachability tests based on diffusion were performed using pure water and salt water as leaching agents. Compact and ground asphalt composites with natural aggregates, and asphalt composites in which the natural aggregates were completely replaced by slag were prepared. The concentrations of total chromium and Cr(VI) were determined in leachates over a time period of 6 mo. After 1 and 6 mo, the concentrations of some other metals were also determined in the leachates. The results indicated that chromium in leachates from asphalt composites with the addition of slag was present almost solely in its hexavalent form. However, the concentrations were very low (below 25 μg L) and did not represent an environmental burden. The leaching of other metals from asphalt composites with the addition of slag was negligible. Therefore, the investigated EAF slag can be considered as environmentally safe substitute for natural aggregates in asphalt mixes. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME V. ELECTRIC ARC FURNACE, MANUAL OF PRACTICE

    EPA Science Inventory

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  2. New algorithm for controlling electric arc furnaces using their vibrational and acoustic characteristics

    NASA Astrophysics Data System (ADS)

    Cherednichenko, V. S.; Bikeev, R. A.; Serikov, V. A.; Rechkalov, A. V.; Cherednichenko, A. V.

    2016-12-01

    The processes occurring in arc discharges are analyzed as the sources of acoustic radiation in an electric arc furnace (EAF). Acoustic vibrations are shown to transform into mechanical vibrations in the furnace laboratory. The shielding of the acoustic energy fluxes onto water-cooled wall panels by a charge is experimentally studied. It is shown that the rate of charge melting and the depth of submergence of arc discharges in the slag and metal melt can be monitored by measuring the vibrational characteristics of furnaces and using them in a universal industrial process-control system, which was developed for EAFs.

  3. Method of operating a centrifugal plasma arc furnace

    DOEpatents

    Kujawa, Stephan T.; Battleson, Daniel M.; Rademacher, Jr., Edward L.; Cashell, Patrick V.; Filius, Krag D.; Flannery, Philip A.; Whitworth, Clarence G.

    1998-01-01

    A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe.sub.3 O.sub.4. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe.sub.2 O.sub.3. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater.

  4. Method of operating a centrifugal plasma arc furnace

    DOEpatents

    Kujawa, S.T.; Battleson, D.M.; Rademacher, E.L. Jr.; Cashell, P.V.; Filius, K.D.; Flannery, P.A.; Whitworth, C.G.

    1998-03-24

    A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe{sub 3}O{sub 4}. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe{sub 2}O{sub 3}. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater. 3 figs.

  5. High-bandwidth continuous-flow arc furnace

    DOEpatents

    Hardt, David E.; Lee, Steven G.

    1996-01-01

    A high-bandwidth continuous-flow arc furnace for stream welding applications includes a metal mass contained in a crucible having an orifice. A power source charges an electrode for generating an arc between the electrode and the mass. The arc heats the metal mass to a molten state. A pressurized gas source propels the molten metal mass through the crucible orifice in a continuous stream. As the metal is ejected, a metal feeder replenishes the molten metal bath. A control system regulates the electrode current, shielding gas pressure, and metal source to provide a continuous flow of molten metal at the crucible orifice. Independent control over the electrode current and shield gas pressure decouples the metal flow temperature and the molten metal flow rate, improving control over resultant weld characteristics.

  6. High-bandwidth continuous-flow arc furnace

    DOEpatents

    Hardt, D.E.; Lee, S.G.

    1996-08-06

    A high-bandwidth continuous-flow arc furnace for stream welding applications includes a metal mass contained in a crucible having an orifice. A power source charges an electrode for generating an arc between the electrode and the mass. The arc heats the metal mass to a molten state. A pressurized gas source propels the molten metal mass through the crucible orifice in a continuous stream. As the metal is ejected, a metal feeder replenishes the molten metal bath. A control system regulates the electrode current, shielding gas pressure, and metal source to provide a continuous flow of molten metal at the crucible orifice. Independent control over the electrode current and shield gas pressure decouples the metal flow temperature and the molten metal flow rate, improving control over resultant weld characteristics. 4 figs.

  7. 20. DETAILED OBLIQUE VIEW SOUTHWEST FURNACE 2, SHOWING STEEL FRAME ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. DETAILED OBLIQUE VIEW SOUTHWEST FURNACE 2, SHOWING STEEL FRAME BOXES FOR COUNTERWEIGHTS, AND FURNACE HEATING PIPES AT RIGHT. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  8. Effect of electric arc furnace slag on growth and physiology of maize (Zea mays L.).

    PubMed

    Radić, Sandra; Crnojević, Helena; Sandev, Dubravka; Jelić, Sonja; Sedlar, Zorana; Glavaš, Katarina; Pevalek-Kozlina, Branka

    2013-12-01

    Basic slag, used in this study as a potential source of certain nutrients, is a byproduct of the production of steel in electric arc furnace (EAF). A pot experiment with two nutrient-poor substrates was conducted to investigate to compare the effect of EAF steel slag and fertilizers NPK + F e on growth and availability of specific nutrients to maize. Mineral content of both substrate and plant leaves, growth, chlorophyll fluorescence and photosynthetic pigments were measured following six weeks of cultivation. As steel slag also contains trace amounts of heavy metals, certain oxidative parameters (antioxidative enzyme activities and lipid peroxidation) were evaluated as well. The steel slag improved soil mineral composition, increased above ground maize biomass by providing Fe, Mn, Mg, K and partly P and improved photosynthetic parameters. The potential phytotoxicity of EAF slag containing substrates was not determined as evaluated by MDA (malondialdehyde), GR (glutathione reductase) and APX (ascorbate peroxidase) levels. The obtained results show that EAF steel slag is comparable to NPK + F e in supplying nutrients for maize growth, indicating the potential of EAF steel slag as an inexpensive and non-phytotoxic nutrient supplier especially in poor soils.

  9. Diagnostics for a waste processing plasma arc furnace (invited) (abstract)a)

    NASA Astrophysics Data System (ADS)

    Woskov, P. P.

    1995-01-01

    Maintaining the quality of our environment has become an important goal of society. As part of this goal new technologies are being sought to clean up hazardous waste sites and to treat ongoing waste streams. A 1 MW pilot scale dc graphite electrode plasma arc furnace (Mark II) has been constructed at MIT under a joint program among Pacific Northwest Laboratory (PNL), MIT, and Electro-Pyrolysis, Inc. (EPI)c) for the remediation of buried wastes in the DOE complex. A key part of this program is the development of new and improved diagnostics to study, monitor, and control the entire waste remediation process for the optimization of this technology and to safeguard the environment. Continuous, real time diagnostics are needed for a variety of the waste process parameters. These parameters include internal furnace temperatures, slag fill levels, trace metals content in the off-gas stream, off-gas molecular content, feed and slag characterization, and off-gas particulate size, density, and velocity distributions. Diagnostics are currently being tested at MIT for the first three parameters. An active millimeter-wave radiometer with a novel, rotatable graphite waveguide/mirror antenna system has been implemented on Mark II for the measurement of surface emission and emissivity which can be used to determine internal furnace temperatures and fill levels. A microwave torch plasma is being evaluated for use as a excitation source in the furnace off-gas stream for continuous atomic emission spectroscopy of trace metals. These diagnostics should find applicability not only to waste remediation, but also to other high temperature processes such as incinerators, power plants, and steel plants.

  10. 30. Photocopy of photograph. STEEL PLANT, OPEN HEARTH FURNACE CHARGING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. Photocopy of photograph. STEEL PLANT, OPEN HEARTH FURNACE CHARGING CREW, 1910. (From the Bethlehem Steel Corporation Colletion, Seattle, WA) - Irondale Iron & Steel Plant, Port Townsend, Jefferson County, WA

  11. Nonlinear system identification of the reduction nickel oxide smelting process in electric arc furnace

    NASA Astrophysics Data System (ADS)

    Gubin, V.; Firsov, A.

    2018-03-01

    As the title implies the article describes the nonlinear system identification of the reduction smelting process of nickel oxide in electric arc furnaces. It is suggested that for operational control ratio of components of the charge must be solved the problem of determining the qualitative composition of the melt in real time. The use of 0th harmonic of phase voltage AC furnace as an indirect measure of the melt composition is proposed. Brief description of the mechanism of occurrence and nature of the non-zero 0th harmonic of the AC voltage of the arc is given. It is shown that value of 0th harmonic of the arc voltage is not function of electrical parameters but depends of the material composition of the melt. Processed industrial data are given. Hammerstein-Wiener model is used for description of the dependence of 0th harmonic of the furnace voltage from the technical parameters of melting furnace: the melt composition and current. Recommendations are given about the practical use of the model.

  12. 40 CFR 63.10686 - What are the requirements for electric arc furnaces and argon-oxygen decarburization vessels?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of... Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... from each EAF (including charging, melting, and tapping operations) and argon-oxygen decarburization...

  13. 40 CFR 63.10686 - What are the requirements for electric arc furnaces and argon-oxygen decarburization vessels?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of... Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... from each EAF (including charging, melting, and tapping operations) and argon-oxygen decarburization...

  14. 40 CFR 63.10686 - What are the requirements for electric arc furnaces and argon-oxygen decarburization vessels?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of... Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... from each EAF (including charging, melting, and tapping operations) and argon-oxygen decarburization...

  15. 40 CFR 63.10686 - What are the requirements for electric arc furnaces and argon-oxygen decarburization vessels?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of... Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... from each EAF (including charging, melting, and tapping operations) and argon-oxygen decarburization...

  16. 40 CFR 63.10686 - What are the requirements for electric arc furnaces and argon-oxygen decarburization vessels?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of... Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... from each EAF (including charging, melting, and tapping operations) and argon-oxygen decarburization...

  17. Waste Heat Recovery from High Temperature Off-Gases from Electric Arc Furnace

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nimbalkar, Sachin U; Thekdi, Arvind; Keiser, James R

    2014-01-01

    This article presents a study and review of available waste heat in high temperature Electric Arc Furnace (EAF) off gases and heat recovery techniques/methods from these gases. It gives details of the quality and quantity of the sensible and chemical waste heat in typical EAF off gases, energy savings potential by recovering part of this heat, a comprehensive review of currently used waste heat recovery methods and potential for use of advanced designs to achieve a much higher level of heat recovery including scrap preheating, steam production and electric power generation. Based on our preliminary analysis, currently, for all electricmore » arc furnaces used in the US steel industry, the energy savings potential is equivalent to approximately 31 trillion Btu per year or 32.7 peta Joules per year (approximately $182 million US dollars/year). This article describes the EAF off-gas enthalpy model developed at Oak Ridge National Laboratory (ORNL) to calculate available and recoverable heat energy for a given stream of exhaust gases coming out of one or multiple EAF furnaces. This Excel based model calculates sensible and chemical enthalpy of the EAF off-gases during tap to tap time accounting for variation in quantity and quality of off gases. The model can be used to estimate energy saved through scrap preheating and other possible uses such as steam generation and electric power generation using off gas waste heat. This article includes a review of the historical development of existing waste heat recovery methods, their operations, and advantages/limitations of these methods. This paper also describes a program to develop and test advanced concepts for scrap preheating, steam production and electricity generation through use of waste heat recovery from the chemical and sensible heat contained in the EAF off gases with addition of minimum amount of dilution or cooling air upstream of pollution control equipment such as bag houses.« less

  18. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission...

  19. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission...

  20. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission...

  1. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission...

  2. Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing.

    PubMed

    Liapis, Ioannis; Papayianni, Ioanna

    2015-01-01

    Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Recycling of an electric arc furnace flue dust to obtain high grade ZnO.

    PubMed

    Ruiz, Oscar; Clemente, Carmen; Alonso, Manuel; Alguacil, Francisco Jose

    2007-03-06

    The production of steel in electric arc furnace (EAF) generates a by-product called EAF dusts. These steelmaking flue dusts are classified in most industrialized countries as hazardous residues because the heavy metals contained in them, tend to leach under slightly acidic rainfall conditions. However, and at the same time they contain zinc species which can be used as a source to obtain valuable by-products. The present investigation shows results on the processing of an EAF flue dust using ammonium carbonate solutions. Once zinc is dissolved: ZnO + 4NH3 + H2O --> Zn(NH3)4(2+) + 2OH- with other impurities (i.e. cadmium and copper), these are eliminated from the zinc solution via cementation with metallic zinc. The purified zinc solution was evaporated (distilled) until precipitation of a zinc carbonate species, which then was calcined to yield a zinc oxide of a high grade. For the unattacked dust residue from the leaching operation, mainly composed of zinc ferrite, several options can be considered: back-recycling to the furnace, further treatment by sodium hydroxide processing or a more safely dumping due to its relatively inertness.

  4. High-Purity Composite Briquette for Direct UMG-Si Production in Arc Furnaces

    NASA Astrophysics Data System (ADS)

    Perruchoud, Raymond; Fischer, Jean-Claude

    2013-12-01

    In metallurgical grade Si (MG-Si), the coal (B) and charcoal (P) contents are on average above 30 ppm as the carbon reduction materials used in the arc furnace are either rich in B or in P. A decrease of both impurities by a factor of 3 using purer raw materials would allow for the direct production of the upgraded metallurgical grade (UMG).This would significantly improve the efficiency of the resulting photovoltaic (PV) cells made with the refined solar grade silicon (SoG-Si) or massively decrease the costs of Si purification by shortening the number of steps needed for reaching B and P contents below 1 ppm requested for the SoG-Si used for the PV cells. A composite C/SiO2 briquette fulfilling the purity targets for the direct production of UMG-Si in the arc furnace was developed. The composite contains several carbon materials with different levels of reactivities and quartz sand. The raw materials aspects, the paste and briquette preparation, as well as the final carbonization step are discussed. The finished briquettes are free of volatiles and are mechanically and thermally very stable, thus, ensuring stable arc furnace charges with minimum losses of dust and SiO gas. Semi-industrial trials including the downstream purification steps for the production of SoG-Si by a metallurgical low-cost route are contemplated.

  5. DC graphite arc furnace, a simple system to reduce mixed waste volume

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wittle, J.K.; Hamilton, R.A.; Trescot, J.

    1995-12-31

    The volume of low-level radioactive waste can be reduced by the high temperature in a DC Graphite Arc Furnace. This volume reduction can take place with the additional benefit of having the solid residue being stabilized by the vitrified product produced in the process. A DC Graphite Arc Furnace is a simple system in which electricity is used to generate heat to vitrify the material and thermally decompose any organic matter in the waste stream. Examples of this type of waste are protective clothing, resins, and grit blast materials produced in the nuclear industry. The various Department of Energy (DOE)more » complexes produce similar low-level waste streams. Electro-Pyrolysis, Inc. and Svedala/Kennedy Van Saun are engineering and building small 50-kg batch and up to 3,000 kg/hr continuous feed DC furnaces for the remediation, pollution prevention, and decontamination and decommissioning segments of the treatment community. This process has been demonstrated under DOE sponsorship at several facilities and has been shown to produce stable waste forms from surrogate waste materials.« less

  6. Hybrid Laser-Arc Welding Tanks Steels

    NASA Astrophysics Data System (ADS)

    Turichin, G.; Tsibulskiy, I.; Kuznetsov, M.; Akhmetov, A.; Klimova-Korsmik, O.

    2016-04-01

    The results investigate hybrid laser-arc welding of high strength steels using design responsible metallic construction and the highest strength body of vehicles. Welds from modern high strength steels grade Hardox 400, Hardox 450, Armox 600T and AB were created. High power fiber laser LS-15 with output 15 kW and arc rectifier VDU - 1500 DC were used in the experiment. Results of the metallographic research and mechanical tests are presented.

  7. Evaluation of electric arc furnace-processed steel slag for dermal corrosion, irritation, and sensitization from dermal contact.

    PubMed

    Suh, Mina; Troese, Matthew J; Hall, Debra A; Yasso, Blair; Yzenas, John J; Proctor, Debora M

    2014-12-01

    Electric arc furnace (EAF) steel slag is alkaline (pH of ~11-12) and contains metals, most notably chromium and nickel, and thus has potential to cause dermal irritation and sensitization at sufficient dose. Dermal contact with EAF slag occurs in many occupational and environmental settings because it is used widely in construction and other industrial sectors for various applications including asphaltic paving, road bases, construction fill, and as feed for cement kilns construction. However, no published study has characterized the potential for dermal effects associated with EAF slag. To assess dermal irritation, corrosion and sensitizing potential of EAF slag, in vitro and in vivo dermal toxicity assays were conducted based on the Organisation for Economic Co-operation and Development (OECD) guidelines. In vitro dermal corrosion and irritation testing (OECD 431 and 439) of EAF slag was conducted using the reconstructed human epidermal (RHE) tissue model. In vivo dermal toxicity and delayed contact sensitization testing (OECD 404 and 406) were conducted in rabbits and guinea pigs, respectively. EAF slag was not corrosive and not irritating in any tests. The results of the delayed contact dermal sensitization test indicate that EAF slag is not a dermal sensitizer. These findings are supported by the observation that metals in EAF slag occur as oxides of low solubility with leachates that are well below toxicity characteristic leaching procedure (TCLP) limits. Based on these results and in accordance to the OECD guidelines, EAF slag is not considered a dermal sensitizer, corrosive or irritant. Copyright © 2014 John Wiley & Sons, Ltd.

  8. Dross treatment in a rotary arc furnace with graphite electrodes

    NASA Astrophysics Data System (ADS)

    Drouet, Michel G.; Handfield, My; Meunier, Jean; Laflamme, Claude B.

    1994-05-01

    Aluminum baths are always covered with a layer of dross resulting from the aluminum surface oxidation. This dross represents 1-10% of the melt and may contain up to 75wt.% aluminum. Since aluminum production is highly energy intensive, dross recycling is very attractive from both energy and economic standpoints. The conventional recycling process using salt rotary furnaces is thermally inefficient and environmentally unacceptable because of the production of salt slags. Hydro-Quebec has developed a new technology using a rotary arc furnace with graphite electrodes. This process provides aluminum recovery rates of 80-90%, using a highly energy efficient, environmentally sound production method.

  9. The efficiency of quartz addition on electric arc furnace (EAF) carbon steel slag stability.

    PubMed

    Mombelli, D; Mapelli, C; Barella, S; Gruttadauria, A; Le Saout, G; Garcia-Diaz, E

    2014-08-30

    Electric arc furnace slag (EAF) has the potential to be re-utilized as an alternative to stone material, however, only if it remains chemically stable on contact with water. The presence of hydraulic phases such as larnite (2CaO SiO2) could cause dangerous elements to be released into the environment, i.e. Ba, V, Cr. Chemical treatment appears to be the only way to guarantee a completely stable structure, especially for long-term applications. This study presents the efficiency of silica addition during the deslagging period. Microstructural characterization of modified slag was performed by SEM and XRD analysis. Elution tests were performed according to the EN 12457-2 standard, with the addition of silica and without, and the obtained results were compared. These results demonstrate the efficiency of the inertization process: the added silica induces the formation of gehlenite, which, even in caustic environments, does not exhibit hydraulic behaviour. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. 6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL VIEW OF SPIN FORM FURNACE FOR STAINLESS STEEL FABRICATION. STAINLESS STEEL WAS MACHINED IN SIDE A OF THE BUILDING, BEGINNING IN 1957. (4/24/78) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  11. [The industrial environment in the electric-furnace steel smelting, converter and open-hearth furnace methods of manufacturing manganese-alloyed steels].

    PubMed

    Karnaukh, N G; Petrov, G A; Gapon, V A; Poslednichenko, I P; Shmidt, S E

    1992-01-01

    Inspection of the environment in manganese-alloyed steel production showed inadequate hygienic conditions of the technological processes employed. Air was more polluted by manganese oxides during the oxygen-converter process though their highest concentrations, 38 times exceeding the MAS, appeared during the casting of steel. An electric furnace coated by dust-noise-proof material and gas cleaning is preferable from a hygienic point of view. The influence of unfavourable microclimate, intensive infrared irradiation and loud noise on workers necessitates automation and mechanization of the process in order to improve the working conditions.

  12. DC Electric Arc Furnace Application for Production of Nickel-Boron Master Alloys

    NASA Astrophysics Data System (ADS)

    Alkan, Murat; Tasyürek, Kerem Can; Bugdayci, Mehmet; Turan, Ahmet; Yücel, Onuralp

    2017-09-01

    In this study, nickel-boron (Ni-B) alloys were produced via a carbothermic reduction starting from boric acid (H3BO3) with high-purity nickel oxide (NiO), charcoal, and wood chips in a direct current arc furnace. In electric arc furnace experiments, different starting mixtures were used, and their effects on the chemical compositions of the final Ni-B alloys were investigated. After the reduction and melting stages, Ni-B alloys were obtained by tapping from the bottom of the furnace. The samples from the designated areas were also taken and analyzed. The chemical composition of the final alloys and selected samples were measured with wet chemical analysis. The Ni-B alloys had a composition of up to 14.82 mass% B. The phase contents of the final alloys and selected samples were measured using x-ray diffraction (XRD). The XRD data helped predict possible reactions and reaction mechanisms. The material and energy balance calculations were made via the XRD Rietveld and chemical compositions. Nickel boride phases started to form 600 mm below the surface. The targeted NiB phase was detected at the tapping zone of the crucible (850-900 mm depth). The energy consumption was 1.84-4.29 kWh/kg, and the electrode consumption was 10-12 g/kg of raw material charged.

  13. Dissipation of Electrical Energy in Submerged Arc Furnaces Producing Silicomanganese and High-Carbon Ferromanganese

    NASA Astrophysics Data System (ADS)

    Steenkamp, Joalet Dalene; Hockaday, Christopher James; Gous, Johan Petrus; Nzima, Thabo Witness

    2017-09-01

    Submerged-arc furnace technology is applied in the primary production of ferroalloys. Electrical energy is dissipated to the process via a combination of arcing and resistive heating. In processes where a crater forms between the charge zone and the reaction zone, electrical energy is dissipated mainly through arcing, e.g., in coke-bed based processes, through resistive heating. Plant-based measurements from a device called "Arcmon" indicated that in silicomanganese (SiMn) production, at times up to 15% of the electrical energy used is transferred by arcing, 30% in high-carbon ferromanganese (HCFeMn) production, compared with 5% in ferrochromium and 60% in ferrosilicon production. On average, the arcing is much less at 3% in SiMn and 5% in HCFeMn production.

  14. Effect of basicity on beneficiated chromite sand smelting process using submerged arc furnace

    NASA Astrophysics Data System (ADS)

    Nurjaman, F.; Subandrio, S.; Ferdian, D.; Suharno, Bambang

    2018-05-01

    Ferrochrome is an important alloy in stainless steel making due to its contribution to high strength and corrosion resistance. In this present study, ferrochrome was derived from Indonesian chromite sand with low-grade Cr/Fe ratio. In order to improve the ratio, beneficiation process such as pre-magnetic separation and reduction process at 1000°C for 60 minutes was required. The process followed by another magnetic separation, thus the Cr/Fe ratio was increased from 0.9 to 1.6. The reduction process used coconut shell charcoal as reductant and limestone as an additive. The beneficiated sand chromite was briquette using bentonite as a binder in 2 wt.% before it was smelted in a submerged electric arc furnace to produce ferrochrome. Basicity was controlled by the addition of limestone and it was varied from 0.4-1.6. Furthermore, the composition of ferrochrome was analyzed by using X-Ray Fluorescence. From this experiment, the result showed that chromium recovery and specific energy was decreased with the increasing of slag basicity.

  15. Walking beam furnace well-way slot covers at Rouge Steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campbell, F. Jr.; Meinzinger, A.D.; Faust, C.H.

    1993-07-01

    Rouge Steel's 68-in. hot strip mill is served by three walking beam slab reheat furnaces. The first two were commissioned in 1974 and the third was installed in 1980. During the period 1979 to 1981, an intensive plant-wide energy management program to reduce energy consumption was undertaken. A major part of that program involved a comprehensive upgrading of refractory and insulation systems utilized in the walking beam reheat furnaces. A durable system for reducing heat losses through the well-way floor openings associated with walking beam slab reheat furnaces has, in addition to 4 to 5% savings in fuel consumption, reducedmore » maintenance costs. Payback is achieved in four to five months.« less

  16. Achieving zero waste of municipal incinerator fly ash by melting in electric arc furnaces while steelmaking.

    PubMed

    Yang, Gordon C C; Chuang, Tsun-Nan; Huang, Chien-Wen

    2017-04-01

    The main objective of this work was to promote zero waste of municipal incinerator fly ash (MIFA) by full-scale melting in electric arc furnaces (EAFs) of steel mini mills around the world. MIFA, generally, is considered as a hazardous waste. Like in many countries, MIFA in Taiwan is first solidified/stabilized and then landfilled. Due to the scarcity of landfill space, the cost of landfilling increases markedly year by year in Taiwan. This paper presents satisfactory results of treating several hundred tons of MIFA in a full-scale steel mini mill using the approach of "melting MIFA while EAF steelmaking", which is somewhat similar to "molten salt oxidation" process. It was found that this practice yielded many advantages such as (1) about 18wt% of quicklime requirement in EAF steelmaking can be substituted by the lime materials contained in MIFA; (2) MIFA would totally end up as a material in fractions of recyclable EAF dust, oxidized slag and reduced slag; (3) no waste is needed for landfilling; and (4) a capital cost saving through the employment of existing EAFs in steel mini mills instead of building new melting plants for the treatment of MIFA. Thus, it is technically feasible to achieve zero waste of MIFA by the practice of this innovative melting technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Recent developments in blast furnace process control within British Steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Warren, P.W.

    1995-12-01

    British Steel generally operates seven blast furnaces on four integrated works. All furnaces have been equipped with comprehensive instrumentation and data logging computers over the past eight years. The four Scunthorpe furnaces practice coal injection up to 170 kg/tHM (340 lb/THM), the remainder injecting oil at up to 100 kg/tHM (200 lb/THM). Distribution control is effected by Paul Wurth Bell-Less Tops on six of the seven furnaces, and Movable Throat Armour with bells on the remaining one. All have at least one sub burden probe. The blast furnace operator has a vast quantity of data and signals to consider andmore » evaluate when attempting to achieve the objective of providing a consistent supply of hot metal. Techniques have been, and are being, developed to assist the operator to interpret large numbers of signals. A simple operator guidance system has been developed to provide advice, based on current operating procedures and interpreted data. Further development will involve the use of a sophisticated Expert System software shell.« less

  18. Concrete with steel furnace slag and fractionated reclaimed asphalt pavement.

    DOT National Transportation Integrated Search

    2014-09-01

    Steel furnace slag (SFS) is an industrial by-product material that can contain free calcium oxide (CaO) and free magnesium oxide (MgO), both : of which can cause significant expansion when hydrated. SFS aggregates are therefore not commonly used in c...

  19. Formation of the ZnFe2O4 phase in an electric arc furnace off-gas treatment system.

    PubMed

    Suetens, T; Guo, M; Van Acker, K; Blanpain, B

    2015-04-28

    To better understand the phenomena of ZnFe2O4 spinel formation in electric arc furnace dust, the dust was characterized with particle size analysis, X-ray fluorescence (XRF), electron backscatter diffraction (EBSD), and electron probe micro-analysis (EPMA). Different ZnFe2O4 formation reaction extents were observed for iron oxide particles with different particle sizes. ZnO particles were present as both individual particles and aggregated on the surface of larger particles. Also, the slag particles found in the off-gas were shown not to react with the zinc vapor. After confirming the presence of a ZnFe2O4 formation reaction, the thermodynamic feasibility of in-process separation - a new electric arc furnace dust treatment technology - was reevaluated. The large air intake and the presence of iron oxide particles in the off-gas were included into the thermodynamic calculations. The formation of the stable ZnFe2O4 spinel phase was shown to be thermodynamically favorable in current electric arc furnace off-gas ducts conditions even before reaching the post combustion chamber. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Paired Straight Hearth Furnace - Transformational Ironmaking Process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lu, Wei-Kao; Debski, Paul

    2014-11-19

    The U. S. steel industry has reduced its energy intensity per ton of steel shipped by 33% since 1990. However, further significant gains in energy efficiency will require the development of new, transformational iron and steelmaking processes. The Paired Straight Hearth Furnace (PSH) process is an emerging alternative high productivity, direct reduced iron (DRI) technology that may achieve very low fuel rates and has the potential to replace blast furnace ironmaking. The PSH furnace can operate independently or may be coupled with other melting technologies to produce liquid hot metal that is both similar to blast furnace iron and suitablemore » as a feedstock for basic oxygen steelmaking furnaces. The PSH process uses non-metallurgical coal as a reductant to convert iron oxides such as iron ore and steelmaking by-product oxides to DRI pellets. In this process, a multi-layer, nominally 120mm tall bed of composite “green balls” made from oxide, coal and binder is built up and contained within a moving refractory hearth. The pellet bed absorbs radiant heat energy during exposure to the high temperature interior refractory surfaces of the PSH while generating a strongly reducing gas atmosphere in the bed that yields a highly metalized DRI product. The PSH concept has been well tested in static hearth experiments. A moving bed design is being developed. The process developers believe that if successful, the PSH process has the potential to replace blast furnaces and coke ovens at a fraction of the operating and capital cost while using about 30% less energy relative to current blast furnace technology. DRI output could also feed electric arc furnaces (EAFs) by displacing a portion of the scrap charge.« less

  1. Method for processing aluminum spent potliner in a graphite electrode ARC furnace

    DOEpatents

    O'Connor, William K.; Turner, Paul C.; Addison, Gerald W.

    2002-12-24

    A method of processing spent aluminum pot liner containing carbon, cyanide compositions, fluorides and inorganic oxides. The spent aluminum pot liner is crushed iron oxide is added to form an agglomerated material. The agglomerated material is melted in an electric arc furnace having the electrodes submerged in the molten material to provide a reducing environment during the furnace operation. In the reducing environment, pot liner is oxidized while the iron oxides are reduced to produce iron and a slag substantially free of cyanide compositions and fluorides. An off-gas including carbon oxides and fluorine is treated in an air pollution control system with an afterburner and a scrubber to produce NaF, water and a gas vented to the atmosphere free of cyanide compositions, fluorine and CO.

  2. Intelligent Support System of Steel Technical Preparation in an Arc Furnace: Functional Scheme of Interactive Builder of the Multi Objective Optimization Problem

    NASA Astrophysics Data System (ADS)

    Logunova, O. S.; Sibileva, N. S.

    2017-12-01

    The purpose of the study is to increase the efficiency of the steelmaking process in large capacity arc furnace on the basis of implementation a new decision-making system about the composition of charge materials. The authors proposed an interactive builder for the formation of the optimization problem, taking into account the requirements of the customer, normative documents and stocks of charge materials in the warehouse. To implement the interactive builder, the sets of deterministic and stochastic model components are developed, as well as a list of preferences of criteria and constraints.

  3. Studies to overcome the manufacturing problems in blast furnace tap hole clay of Integrated Steel Plants: Experimental approach

    NASA Astrophysics Data System (ADS)

    Siva kumar, R.; Mohammed, Raffi; Srinivasa Rao, K.

    2018-03-01

    Integrated Steel Plants commonly uses Blast Furnace route for iron production which accounts for over 60 % of the world iron output. Blast Furnace runs for ten to twenty years without repairing hearth walls and Tap Hole (TH). Tap hole is an outlet for hot metal produced in a Blast Furnace and run from the shell of the furnace into the interior allowing access to the molten material. Tapping is the term used for drilling a hole through the tap hole which allows the molten iron and slag to flow out. In Iron making process, removal of liquid iron from furnace and sending it for steel making is known as cast house practice. For tapping liquid iron and operating the tap hole requires a special type of clay. Tap hole clay (THC) used to stop the flow of liquid iron and slag from the blast furnace. Present work deals with the study on manufacturing of THC at Visakhapatnam Steel Plant and problems related to manufacturing. Experiments were conducted to solve the identified problems and results are furnished in detail. The findings can improve the manufacturing process and improve the productivity of tap hole clay.

  4. Investigations on phosphorus recovery and reuse as soil amendment from electric arc furnace slag filters.

    PubMed

    Bird, Simon C; Drizo, Aleksandra

    2009-11-01

    Electric arc furnace (EAF) steel slag has been identified as an effective filter material for the removal of phosphorus (P) from both point and non-point sources. To determine the feasibility of land-applying P saturated EAF steel slag this study was undertaken to investigate (i) saturated EAF steel slag material's potential as a P fertilizer or soil amendment and (ii) P desorption and metals leachate from saturated EAF steel slag material to surface runoff. Medicago sativa (alfalfa) was planted in a nutrient depleted washed sand media. Phosphorus was added either as saturated EAF steel slag or as a standard commercial phosphate fertilizer in order to assess the plant availability of the P from saturated EAF steel slag. Four different P application levels were tested: a low (20 lbs acre furrow slice(-1) (5.5 g P m(-3))) two medium (40 and 60 lbs. acre f.s.(-1) (11 and 16.5 g P m(-3))) and a high (120 lbs. acre f.s.(-1) (33 g P m(-3))). The above-ground biomass of half of the plants was harvested after 5 weeks and the second half at 10 weeks. All treatments regardless of the P source used showed high rates of germination. At the first harvest period (5 weeks) significantly higher above-ground biomass (p < 0.01) was seen at the 3 highest P amendment rates in treatments with triple super phosphate fertilizer (TSP) than with EAF steel slag. However, by the second harvest (10 weeks) only the highest amendment rate of TSP showed a significantly higher amount of biomass (p < 0.01), suggesting that EAF steel slag might be an effective slow release P source. In a second experiment, a rain simulator was used to assess desorption of DRP, TP and metals from a saturated and semi-saturated EAF steel slag. The results revealed that the total amounts of DRP and TP released to surface runoff from EAF steel slag were negligible when compared to the total quantities of P retained by this material. Overall the results from this study demonstrated that once the EAF steel slag filter

  5. Microstructural changes of a thermally aged stainless steel submerged arc weld overlay cladding of nuclear reactor pressure vessels

    NASA Astrophysics Data System (ADS)

    Takeuchi, T.; Kameda, J.; Nagai, Y.; Toyama, T.; Matsukawa, Y.; Nishiyama, Y.; Onizawa, K.

    2012-06-01

    The effect of thermal aging on microstructural changes in stainless steel submerged arc weld-overlay cladding of reactor pressure vessels was investigated using atom probe tomography (APT). In as-received materials subjected to post-welding heat treatments (PWHTs), with a subsequent furnace cooling, a slight fluctuation of the Cr concentration was observed due to spinodal decomposition in the δ-ferrite phase but not in the austenitic phase. Thermal aging at 400 °C for 10,000 h caused not only an increase in the amplitude of spinodal decomposition but also the precipitation of G phases with composition ratios of Ni:Si:Mn = 16:7:6 in the δ-ferrite phase. The degree of the spinodal decomposition in the submerged arc weld sample was similar to that in the electroslag weld one reported previously. We also observed a carbide on the γ-austenite and δ-ferrite interface. There were no Cr depleted zones around the carbide.

  6. Steel industry energy consumption: Sensitivity to technology choice, fuel prices, and carbon prices

    EIA Publications

    2016-01-01

    Steel industry energy consumption in 2010 totaled 1,158 trillion British thermal units (Btu), representing 8% of total manufacturing energy consumption. Energy consumption in the steel industry is largely for crude steel production using basic oxygen furnace (BOF) and electric arc furnace (EAF) technologies. Overall energy intensity in EAF, used primarily to melt scrap steel, is significantly lower than in BOF which is used to create virgin steel from iron ore. Over the past two decades, a shift from BOF to EAF has contributed to a substantial reduction in the energy intensity of the U.S. steel industry. From 1991 to 2010, the EAF share of total U.S. steel production in physical units increased from 38% to 61%, and the overall energy intensity of crude steel production in Btu per metric ton decreased by 37%.

  7. High temperature furnace modeling and performance verifications

    NASA Technical Reports Server (NTRS)

    Smith, James E., Jr.

    1992-01-01

    Analytical, numerical, and experimental studies were performed on two classes of high temperature materials processing sources for their potential use as directional solidification furnaces. The research concentrated on a commercially available high temperature furnace using a zirconia ceramic tube as the heating element and an Arc Furnace based on a tube welder. The first objective was to assemble the zirconia furnace and construct parts needed to successfully perform experiments. The 2nd objective was to evaluate the zirconia furnace performance as a directional solidification furnace element. The 3rd objective was to establish a data base on materials used in the furnace construction, with particular emphasis on emissivities, transmissivities, and absorptivities as functions of wavelength and temperature. A 1-D and 2-D spectral radiation heat transfer model was developed for comparison with standard modeling techniques, and were used to predict wall and crucible temperatures. The 4th objective addressed the development of a SINDA model for the Arc Furnace and was used to design sample holders and to estimate cooling media temperatures for the steady state operation of the furnace. And, the 5th objective addressed the initial performance evaluation of the Arc Furnace and associated equipment for directional solidification. Results of these objectives are presented.

  8. Occupational asthma due to manual metal-arc welding of special stainless steels.

    PubMed

    Hannu, T; Piipari, R; Kasurinen, H; Keskinen, H; Tuppurainen, M; Tuomi, T

    2005-10-01

    Occupational asthma (OA) can be induced by fumes of manual metal-arc welding on stainless steel. In recent years, the use of special stainless steels (SSS) with high chromium content has increased. This study presents two cases of OA caused by manual metal-arc welding on SSS. In both cases, the diagnosis of OA was based on respiratory symptoms, occupational exposure and positive findings in the specific challenge tests. In the first case, a 46-yr-old welder had experienced severe dyspnoea while welding SSS (SMO steel), but not in other situations. Challenge tests with both mild steel and stainless steel using a common electrode were negative. Welding SSS with a special electrode caused a delayed 37% drop in forced expiratory volume in one second (FEV1). In the second case, a 34-yr-old male had started to experience dyspnoea during the past few years, while welding especially SSS (Duplex steel). The workplace peak expiratory flow monitoring was suggestive of OA. Challenge tests with both mild steel and stainless steel using a common electrode did not cause bronchial obstruction. Welding SSS with a special electrode caused a delayed 31% drop in FEV1. In conclusion, exposure to manual metal-arc welding fumes of special stainless steel should be considered as a new cause of occupational asthma.

  9. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME III. BLAST FURNACE IRONMAKING, MANUAL OF PRACTICE

    EPA Science Inventory

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  10. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME IV. OPEN HEARTH FURNACE, MANUAL OF PRACTICE

    EPA Science Inventory

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  11. Gas metal arc weldability of 1.5 GPa grade martensitic steels

    NASA Astrophysics Data System (ADS)

    Hwang, Insung; Yun, Hyeonsang; Kim, Dongcheol; Kang, Munjin; Kim, Young-Min

    2018-01-01

    The gas metal arc weldability of 1.5 GPa grade martensitic (MART) steel was evaluated using both inverter direct current (DC) and DC pulse power type welders, under conditions of different welding currents, welding speeds, and shielding gasses. By investigating the bead appearance, tensile strength, and arc stability, it was determined that DC pulse power is better than inverter DC power for arc welding of 1.3 mm thick 1.5 GPa grade MART steel. Further, from the results of the weldability for various shielding gases, it was determined that mixed shielding gas is more effective for welding 1.5 GPa grade MART steel than is pure inert gas (Ar) or active (CO2) gas. In the case of pure shielding gas, no sound bead was formed under any conditions. However, when the mixed shielding gas was used, sound and fine beads were obtained.

  12. CO2 Mineralization and Utilization using Steel Slag for Establishing a Waste-to-Resource Supply Chain.

    PubMed

    Pan, Shu-Yuan; Chung, Tai-Chun; Ho, Chang-Ching; Hou, Chin-Jen; Chen, Yi-Hung; Chiang, Pen-Chi

    2017-12-08

    Both steelmaking via an electric arc furnace and manufacturing of portland cement are energy-intensive and resource-exploiting processes, with great amounts of carbon dioxide (CO 2 ) emission and alkaline solid waste generation. In fact, most CO 2 capture and storage technologies are currently too expensive to be widely applied in industries. Moreover, proper stabilization prior to utilization of electric arc furnace slag are still challenging due to its high alkalinity, heavy metal leaching potentials and volume instability. Here we deploy an integrated approach to mineralizing flue gas CO 2 using electric arc furnace slag while utilizing the reacted product as supplementary cementitious materials to establish a waste-to-resource supply chain toward a circular economy. We found that the flue gas CO 2 was rapidly mineralized into calcite precipitates using electric arc furnace slag. The carbonated slag can be successfully utilized as green construction materials in blended cement mortar. By this modulus, the global CO 2 reduction potential using iron and steel slags was estimated to be ~138 million tons per year.

  13. UNIVERSITY OF WASHINGTON ELECTROSTATIC SCRUBBER TESTS AT A STEEL PLANT

    EPA Science Inventory

    The report gives results of a demonstration of the effectiveness of a 1700 cu m/hr (1000 acfm) University of Washington (UW) Electrostatic Spray Scrubber in controlling fine particle emissions from an electric-arc steel furnace. The two-stage portable pilot plant operates by comb...

  14. Arc brazing of austenitic stainless steel to similar and dissimilar metals

    NASA Astrophysics Data System (ADS)

    Moschini, Jamie Ian

    There is a desire within both the stainless steel and automotive industries to introduce stainless steel into safety critical areas such as the crumple zone of modem cars as a replacement for low carbon mild steel. The two main reasons for this are stainless steel's corrosion resistance and its higher strength compared with mild steel. It has been anticipated that the easiest way to introduce stainless steel into the automotive industry would be to incorporate it into the existing design. The main obstacle to be overcome before this can take place is therefore how to join the stainless steel to the rest of the car body. In recent times arc brazil g has been suggested as a joining technique which will eliminate many of the problems associated with fusion welding of zinc coated mild steel to stainless steel.Similar and dissimilar parent material arc brazed joints were manufactured using three copper based filler materials and three shielding gases. The joints were tested in terms of tensile strength, impact toughness and fatigue properties. It was found that similar parent material stainless steel joints could be produced with a 0.2% proof stress in excess of the parent material and associated problems such as Liquid Metal Embrittlement were not experienced. Dissimilar parent material joints were manufactured with an ultimate tensile strength in excess of that of mild steel although during fatigue testing evidence of Liquid Metal Embrittlement was seen lowering the mean fatigue load.At the interface of the braze and stainless steel in the similar material butt joints manufactured using short circuit transfer, copper appeared to penetrate the grain boundaries of the stainless steel without embrittling the parent material. Further microscopic investigation of the interface showed that the penetration could be described by the model proposed by Mullins. However, when dissimilar metal butt joints were manufactured using spray arc transfer, penetration of copper into the

  15. Metals purification by improved vacuum arc remelting

    DOEpatents

    Zanner, Frank J.; Williamson, Rodney L.; Smith, Mark F.

    1994-12-13

    The invention relates to improved apparatuses and methods for remelting metal alloys in furnaces, particularly consumable electrode vacuum arc furnaces. Excited reactive gas is injected into a stationary furnace arc zone, thus accelerating the reduction reactions which purify the metal being melted. Additionally, a cooled condensation surface is disposed within the furnace to reduce the partial pressure of water in the furnace, which also fosters the reduction reactions which result in a purer produced ingot. Methods and means are provided for maintaining the stationary arc zone, thereby reducing the opportunity for contaminants evaporated from the arc zone to be reintroduced into the produced ingot.

  16. A Bottom-up Energy Efficiency Improvement Roadmap for China’s Iron and Steel Industry up to 2050

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Qi; Hasanbeigi, Ali; Price, Lynn

    Iron and steel manufacturing is energy intensive in China and in the world. China is the world largest steel producer accounting for around half of the world steel production. In this study, we use a bottom-up energy consumption model to analyze four steel-production and energy-efficiency scenarios and evaluate the potential for energy savings from energy-efficient technologies in China’s iron and steel industry between 2010 and 2050. The results show that China’s steel production will rise and peak in the year 2020 at 860 million tons (Mt) per year for the base-case scenario and 680 Mt for the advanced energy-efficiency scenario.more » From 2020 on, production will gradually decrease to about 510 Mt and 400 Mt in 2050, for the base-case and advanced scenarios, respectively. Energy intensity will decrease from 21.2 gigajoules per ton (G/t) in 2010 to 12.2 GJ/t and 9.9 GJ/t in 2050 for the base-case and advanced scenarios, respectively. In the near term, decreases in iron and steel industry energy intensity will come from adoption of energy-efficient technologies. In the long term, a shift in the production structure of China’s iron and steel industry, reducing the share of blast furnace/basic oxygen furnace production and increasing the share of electric-arc furnace production while reducing the use of pig iron as a feedstock to electric-arc furnaces will continue to reduce the sector’s energy consumption. We discuss barriers to achieving these energy-efficiency gains and make policy recommendations to support improved energy efficiency and a shift in the nature of iron and steel production in China.« less

  17. Distribution of radionuclides during melting of carbon steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thurber, W.C.; MacKinney, J.

    1997-02-01

    During the melting of steel with radioactive contamination, radionuclides may be distributed among the metal product, the home scrap, the slag, the furnace lining and the off-gas collection system. In addition, some radionuclides will pass through the furnace system and vent to the atmosphere. To estimate radiological impacts of recycling radioactive scrap steel, it is essential to understand how radionuclides are distributed within the furnace system. For example, an isotope of a gaseous element (e.g., radon) will exhaust directly from the furnace system into the atmosphere while a relatively non-volatile element (e.g., manganese) can be distributed among all the othermore » possible media. This distribution of radioactive contaminants is a complex process that can be influenced by numerous chemical and physical factors, including composition of the steel bath, chemistry of the slag, vapor pressure of the particular element of interest, solubility of the element in molten iron, density of the oxide(s), steel melting temperature and melting practice (e.g., furnace type and size, melting time, method of carbon adjustment and method of alloy additions). This paper discusses the distribution of various elements with particular reference to electric arc furnace steelmaking. The first two sections consider the calculation of partition ratios for elements between metal and slag based on thermodynamic considerations. The third section presents laboratory and production measurements of the distribution of various elements among slag, metal, and the off-gas collection system; and the final section provides recommendations for the assumed distribution of each element of interest.« less

  18. Scientific and Technological Principles of Development of New Cold-Resistant Arc-Steels (Steels for Arctic Applications)

    NASA Astrophysics Data System (ADS)

    Sych, O. V.; Khlusova, E. I.; Yashin, E. A.

    2017-12-01

    The paper presents the results of quantitative analysis of C, Mn, Ni and Cu content on strength and cold-resistance of rolled plates. Relations between the ferritic-bainitic structure morphology and anisotropy and steel performance characteristics have been established. Influence of thermal and deformation rolling patterns on steel structure has been studied. The steel chemical composition has been improved and precision thermomechanical processing conditions for production of cold-resistant Arc-steel plates have been developed.

  19. Immobilization of Cr (VI) in stainless steel slag and Cd, As, and Pb in wastewater using blast furnace slag via a hydrothermal treatment

    NASA Astrophysics Data System (ADS)

    Tae, Soon-Jae; Morita, Kazuki

    2017-05-01

    The immobilization of hexavalent chromium in stainless steel slag using blast furnace slag as the immobilizing agent and by performing a hydrothermal treatment was investigated. The results showed that there was no immobilization in the absence of the blast furnace slag. On the other hand, the hexavalent chromium in stainless steel slag could be immobilized through the hydrothermal reaction when blast furnace slag was used at 250 °C for 24 h. A leaching test was performed to evaluate the degree of immobilization of hexavalent chromium in the products formed by the hydrothermal reaction. It was found that the degree of immobilization was very high. Based on the results obtained, the immobilization mechanism of hexavalent chromium in stainless steel slag, resulting from the hydrothermal treatment of blast furnace slag, could be elucidated. Finally, the immobilization of cadmium, lead, and arsenic using blast furnace slag as the immobilization agent was also studied while focusing on the effects of the hydrothermal treatment.

  20. In vitro assessment of genotoxic effects of electric arc furnace dust on human lymphocytes using the alkaline comet assay.

    PubMed

    Garaj-Vrhovac, Vera; Orescanin, Visnja; Ruk, Damir; Gajski, Goran

    2009-02-15

    In vitro genotoxic effects of leachates of electric arc furnace dust (EAFD) on human peripheral lymphocytes, assessed prior and following the treatment with a strong alkaline solution were investigated using the alkaline comet assay. Prior and following the treatment, lymphocytes were incubated with leachate of EAFD for 6 and 24 hours at 37 degrees C. Negative controls were also included. Mean values of the tail lengths established in the samples treated with the leachate stemming from the original dust for 6 and 24 hours, were 15.70 microm and 16.78 microm, respectively, as compared to 12.33 microm found in the control sample. Slight, but significant increase in the tail length was also found with the dust treated with a strong alkaline solution (13.37 microm and 13.60 microm). In case of high heavy metal concentrations (the extract of the original furnace dust), the incubation period was revealed to be of significance as well. The obtained results lead to the conclusion that alkaline comet assay could be used as a rapid, sensitive and low-cost tool when assessing genotoxicity of various waste materials, such as leachates of the electric arc furnace dust.

  1. Hybrid/Tandem Laser-Arc Welding of Thick Low Carbon Martensitic Stainless Steel Plates =

    NASA Astrophysics Data System (ADS)

    Mirakhorli, Fatemeh

    High efficiency and long-term life of hydraulic turbines and their assemblies are of utmost importance for the hydropower industry. Usually, hydroelectric turbine components are made of thick-walled low carbon martensitic stainless steels. The assembly of large hydroelectric turbine components has been a great challenge. The use of conventional welding processes involves typical large groove design and multi-pass welding to fill the groove which exposes the weld to a high heat input creating relatively large fusion zone and heat affected zone. The newly-developed hybrid/tandem laser-arc welding technique is believed to offer a highly competitive solution to improve the overall hydro-turbine performance by combining the high energy density and fast welding speed of the laser welding technology with the good gap bridging and feeding ability of the gas metal arc welding process to increase the productivity and reduce the consumable material. The main objective of this research work is to understand different challenges appearing during hybrid laser-arc welding (HLAW) of thick gauge assemblies of low carbon 13%Cr- 4%Ni martensitic stainless steel and find a practical solution by adapting and optimizing this relatively new welding process in order to reduce the number of welding passes necessary to fill the groove gap. The joint integrity was evaluated in terms of microstructure, defects and mechanical properties in both as-welded and post-welded conditions. A special focus was given to the hybrid and tandem laser-arc welding technique for the root pass. Based on the thickness of the low carbon martensitic stainless steel plates, this work is mainly focused on the following two tasks: • Single pass hybrid laser-arc welding of 10-mm thick low carbon martensitic stainless steel. • Multi-pass hybrid/tandem laser-arc welding of 25-mm thick martensitic stainless steel.

  2. Pragmatic analysis of the electric submerged arc furnace continuum

    NASA Astrophysics Data System (ADS)

    Karalis, K.; Karkalos, N.; Antipas, G. S. E.; Xenidis, A.

    2017-09-01

    A transient mathematical model was developed for the description of fluid flow, heat transfer and electromagnetic phenomena involved in the production of ferronickel in electric arc furnaces. The key operating variables considered were the thermal and electrical conductivity of the slag and the shape, immersion depth and applied electric potential of the electrodes. It was established that the principal stimuli of the velocities in the slag bath were the electric potential and immersion depth of the electrodes and the thermal and electrical conductivities of the slag. Additionally, it was determined that, under the set of operating conditions examined, the maximum slag temperature ranged between 1756 and 1825 K, which is in accordance with industrial measurements. Moreover, it was affirmed that contributions to slag stirring due to Lorentz forces and momentum forces due to the release of carbon monoxide bubbles from the electrode surface were negligible.

  3. Pragmatic analysis of the electric submerged arc furnace continuum

    PubMed Central

    Karkalos, N.; Xenidis, A.

    2017-01-01

    A transient mathematical model was developed for the description of fluid flow, heat transfer and electromagnetic phenomena involved in the production of ferronickel in electric arc furnaces. The key operating variables considered were the thermal and electrical conductivity of the slag and the shape, immersion depth and applied electric potential of the electrodes. It was established that the principal stimuli of the velocities in the slag bath were the electric potential and immersion depth of the electrodes and the thermal and electrical conductivities of the slag. Additionally, it was determined that, under the set of operating conditions examined, the maximum slag temperature ranged between 1756 and 1825 K, which is in accordance with industrial measurements. Moreover, it was affirmed that contributions to slag stirring due to Lorentz forces and momentum forces due to the release of carbon monoxide bubbles from the electrode surface were negligible. PMID:28989738

  4. Combinatorial synthesis of phosphors using arc-imaging furnace

    PubMed Central

    Ishigaki, Tadashi; Toda, Kenji; Yoshimura, Masahiro; Uematsu, Kazuyoshi; Sato, Mineo

    2011-01-01

    We have applied a novel ‘melt synthesis technique’ rather than a conventional solid-state reaction to rapidly synthesize phosphor materials. During a synthesis, the mixture of oxides or their precursors is melted by light pulses (10–60 s) in an arc-imaging furnace on a water-cooled copper hearth to form a globule of 1–5 mm diameter, which is then rapidly cooled by turning off the light. Using this method, we synthesized several phosphor compounds including Y3Al5O12:Ce(YAG) and SrAl2O4:Eu,Dy. Complex phosphor oxides are difficult to produce by conventional solid-state reaction techniques because of the slow reaction rates among solid oxides; as a result, the oxides form homogeneous compounds or solid solutions. On the other hand, melt reactions are very fast (10–60 s) and result in homogeneous compounds owing to rapid diffusion and mixing in the liquid phase. Therefore, melt synthesis techniques are suitable for preparing multi component homogeneous compounds and solid solutions. PMID:27877432

  5. Combinatorial synthesis of phosphors using arc-imaging furnace

    NASA Astrophysics Data System (ADS)

    Ishigaki, Tadashi; Toda, Kenji; Yoshimura, Masahiro; Uematsu, Kazuyoshi; Sato, Mineo

    2011-10-01

    We have applied a novel 'melt synthesis technique' rather than a conventional solid-state reaction to rapidly synthesize phosphor materials. During a synthesis, the mixture of oxides or their precursors is melted by light pulses (10-60 s) in an arc-imaging furnace on a water-cooled copper hearth to form a globule of 1-5 mm diameter, which is then rapidly cooled by turning off the light. Using this method, we synthesized several phosphor compounds including Y3Al5O12:Ce(YAG) and SrAl2O4:Eu,Dy. Complex phosphor oxides are difficult to produce by conventional solid-state reaction techniques because of the slow reaction rates among solid oxides; as a result, the oxides form homogeneous compounds or solid solutions. On the other hand, melt reactions are very fast (10-60 s) and result in homogeneous compounds owing to rapid diffusion and mixing in the liquid phase. Therefore, melt synthesis techniques are suitable for preparing multi component homogeneous compounds and solid solutions.

  6. Microstructure and Mechanical Properties of Plasma Arc Brazed AISI 304L Stainless Steel and Galvanized Steel Plates

    NASA Astrophysics Data System (ADS)

    Jin, Yajuan; Li, Ruifeng; Yu, Zhishui; Wang, Yu

    2016-04-01

    Plasma arc brazing is used to join the AISI 304L stainless steel and galvanized steel plate butt joints with the CuSi3Mn1 filler wire. The effect of parameters on weld surface appearance, interfacial microstructure, and composition distribution in the joint was studied. The microhardness and mechanical tests were conducted to determine the mechanical properties of the welded specimens. The results indicated that good appearance, bead shape, and sufficient metallurgical bonding could be obtained when the brazing process was performed with a wire feeding speed of 0.8 m/min, plasma gas flow rate of 3.0 l/min, welding current of 100 A, and welding speed of 27 cm/min. During plasma arc brazing process, the top corner of the stainless steel and galvanized steel plate were heated and melted, and the melted quantity of stainless steel was much more than that of the galvanized steel due to the thermal conductivity coefficient difference between the dissimilar materials. The microhardness test results shows that the microhardness value gradually increased from the side of the galvanized steel to the stainless steel in the joint, and it is good for improving the mechanical properties of joint. The tensile strength was a little higher than that of the brazing filler, and the fracture position of weld joint was at the base metal of galvanized steel plate.

  7. 40 CFR 60.270a - Applicability and designation of affected facility.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After... specialty steels: electric arc furnaces, argon-oxygen decarburization vessels, and dust-handling systems. (b...

  8. 40 CFR 60.270a - Applicability and designation of affected facility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After... specialty steels: electric arc furnaces, argon-oxygen decarburization vessels, and dust-handling systems. (b...

  9. 40 CFR 60.270a - Applicability and designation of affected facility.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After... specialty steels: electric arc furnaces, argon-oxygen decarburization vessels, and dust-handling systems. (b...

  10. 40 CFR 60.270a - Applicability and designation of affected facility.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After... specialty steels: electric arc furnaces, argon-oxygen decarburization vessels, and dust-handling systems. (b...

  11. 40 CFR 60.270a - Applicability and designation of affected facility.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After... specialty steels: electric arc furnaces, argon-oxygen decarburization vessels, and dust-handling systems. (b...

  12. Modeling of Radiative Heat Transfer in an Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Opitz, Florian; Treffinger, Peter; Wöllenstein, Jürgen

    2017-12-01

    Radiation is an important means of heat transfer inside an electric arc furnace (EAF). To gain insight into the complex processes of heat transfer inside the EAF vessel, not only radiation from the surfaces but also emission and absorption of the gas phase and the dust cloud need to be considered. Furthermore, the radiative heat exchange depends on the geometrical configuration which is continuously changing throughout the process. The present paper introduces a system model of the EAF which takes into account the radiative heat transfer between the surfaces and the participating medium. This is attained by the development of a simplified geometrical model, the use of a weighted-sum-of-gray-gases model, and a simplified consideration of dust radiation. The simulation results were compared with the data of real EAF plants available in literature.

  13. Effect of Feed Forms on the Results of Melting of Fly Ash by a DC Plasma Arc Furnace

    NASA Astrophysics Data System (ADS)

    Chen, Mingzhou; Meng, Yuedong; Shi, Jiabiao; Ni, Guohua; Jiang, Yiman; Yu, Xinyao; ZHAO, Peng

    2009-10-01

    Fly ash from a municipal solid waste incinerator (MSWI) without preprocessing (original fly ash, OFA) was melted by a direct current (DC) plasma arc furnace to investigate how the feed forms governed the results. Dioxins in flue gas from stack and bag-filter ash (BFA) were detected. The distribution of heavy metals of Pb, Cd, As, and Cr along the flue gas process system was analyzed. Through a comparison of the results for dioxins and heavy metals in this study and previous work, carrying-over of fly ash particles with the flue gas stream can be deduced. Based on the magnetic induction equation and Navier-Stokes equations, a magnetohydrodynamic (MHD) model for the plasma arc was developed to describe the particle-carrying effect. The results indicate that, a. when melted, the feed forms of MSWI fly ash affect the results significantly; b. it is not preferable to melt MSWI fly ash directly, and efforts should be made to limit the mass transfer of OFA from the plasma furnace.

  14. Hybrid Laser-Arc Welding of the High-Strength Shipbuilding Steels: Equipment and Technology

    NASA Astrophysics Data System (ADS)

    Turichin, G.; Kuznetsov, M.; Tsibulskiy, I.; Firsova, A.

    Hybrid laser-arc welding (HLAW) allows getting weld joints with thickness up to 35 mm for one pass, provide good quality formation of joints, minimal thermal deformations, the productivity in 10 times more in comparison with arc welding. In addition, replacement arc welding to the HLAW allows economizing filler materials, shielding gas and consumable electricity more than 4 times. Therefore, HLAW is actually technology for basic engineering branches and especially for shipbuilding. The Institute of Laser and Welding Technologies (ILWT) developed laser and hybrid laser-arc welding technologies for different type of steels and alloys including high-strength shipbuilding steels. Also ILWT produced portal and robotic systems for HLAW process realization. Portal system for hybrid laser-arc welding of panels with dimensions 6x6 m using at the manufacturing of flat curvilinear sections in the shipbuilding is depicted in the article. Results of experimental researches of the hybrid laser-arc welding parameters influence on the formation and mechanical properties of weld joint are described at the publication also. Experimental part was made with using of the portal system.

  15. Interior of shop, showing the reheat furnaces; the vehicle in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior of shop, showing the reheat furnaces; the vehicle in the center is a charging machine the operator of which manipulates steel ingots in the furnace, as well as in the adjacent forging hammers - Bethlehem Steel Corporation, South Bethlehem Works, Tool Steel-Electric Furnace Shop, Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

  16. Laser-ultrasonic inspection of hybrid laser-arc welded HSLA-65 steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lévesque, D.; Rousseau, G.; Monchalin, J.-P.

    2014-02-18

    The hybrid laser-arc welding (HLAW) process is a relatively low heat input joining technology that combines the synergistic qualities of both the high energy density laser beam for deep penetration and the arc for wide fit-up gap tolerance. This process is especially suitable for the shipbuilding industry where thick-gauge section, long steel plates have been widely used in a butt joint configuration. In this study, preliminary exploration was carried out to detect and visualize the welding defects using laser ultrasonics combined with the synthetic aperture focusing technique (SAFT). Results obtained on 9.3 mm thick butt-welded HSLA-65 steel plates indicated thatmore » the laser-ultrasonic SAFT inspection technique can successfully detect and visualize the presence of porosity, lack of fusion and internal crack defects. This was further confirmed by X-ray digital radiography and metallography. The results obtained clearly show the potential of using the laser-ultrasonic technology for the automated inspection of hybrid laser-arc welds.« less

  17. Laser-ultrasonic inspection of hybrid laser-arc welded HSLA-65 steel

    NASA Astrophysics Data System (ADS)

    Lévesque, D.; Rousseau, G.; Wanjara, P.; Cao, X.; Monchalin, J.-P.

    2014-02-01

    The hybrid laser-arc welding (HLAW) process is a relatively low heat input joining technology that combines the synergistic qualities of both the high energy density laser beam for deep penetration and the arc for wide fit-up gap tolerance. This process is especially suitable for the shipbuilding industry where thick-gauge section, long steel plates have been widely used in a butt joint configuration. In this study, preliminary exploration was carried out to detect and visualize the welding defects using laser ultrasonics combined with the synthetic aperture focusing technique (SAFT). Results obtained on 9.3 mm thick butt-welded HSLA-65 steel plates indicated that the laser-ultrasonic SAFT inspection technique can successfully detect and visualize the presence of porosity, lack of fusion and internal crack defects. This was further confirmed by X-ray digital radiography and metallography. The results obtained clearly show the potential of using the laser-ultrasonic technology for the automated inspection of hybrid laser-arc welds.

  18. Arc Furnace Mercury Capsule

    NASA Image and Video Library

    1959-08-20

    A hot jet research facility, used extensively in the design and development of the reentry heat shield on the Project Mercury spacecraft. The electrically-heated arc jet simulates the friction heating encountered by a space vehicle as it returns to the earth's atmosphere at high velocities. The arc jet was located in Langley's Structures Research Laboratory. It was capable of heating the air stream to about 9,000 degrees F. -- Published in Taken from an October 5, 1961 press release entitled: Hot Jet Research Facility used in Reentry Studies will be demonstrated at NASA Open House, October 7.

  19. An intervention for noise control of blast furnace in steel industry.

    PubMed

    Golmohammadi, Rostam; Giahi, Omid; Aliabadi, Mohsen; Darvishi, Ebrahim

    2014-01-01

    Noise pollution is currently a major health risk factor for workers in industries. The aim of this study was to investigate noise pollution and implement a control intervention plan for blast furnace in a steel industry. The measurement of sound pressure level (SPL) along with frequency analysis was done with the sound-level-meter Cell-450. Personal noise exposure was performed using dosimeter TES-1345 calibrated with CEL-282. Before planning noise controls, acoustic insulation properties of the furnace control unit and workers' rest room were assessed. Control room and workers' rest room were redesigned in order to improve acoustical condition. The SPL before intervention around the Blast Furnace was 90.3 dB (L) and its dominant frequency was 4000 Hz. Besides, noise transmission loss of the control and rest rooms were 10.3 dB and 4.2 dB, respectively. After intervention, noise reduction rates in the control and rest rooms were 27.4 dB and 27.7 dB, respectively. The workers' noise dose before and after the intervention was 240% and less than 100%, respectively. Improvement the workroom acoustic conditions through noise insulation can be considered effective method for preventing workers exposure to harmful noise.

  20. Investigation of the Microstructure of Laser-Arc Hybrid Welded Boron Steel

    NASA Astrophysics Data System (ADS)

    Son, Seungwoo; Lee, Young Ho; Choi, Dong-Won; Cho, Kuk-Rae; Shin, Seung Man; Lee, Youngseog; Kang, Seong-Hoon; Lee, Zonghoon

    2018-05-01

    The microstructure of boron steel for automotive driving shaft manufacturing after laser-arc hybrid welding was investigated. Laser-arc hybrid welding technology was applied to 3-mm-thick plates of boron steel, ST35MnB. The temperature distribution of the welding pool was analyzed using the finite element method, and the microstructure of the welded boron steel was characterized using optical microscopy and scanning and transmission electron microscopies. The microstructure of the weld joint was classified into the fusion zone, the heat-affected zone (HAZ), and the base material. At the fusion zone, the bainite grains exist in the martensite matrix and show directionality because of heat input from the welding. The HAZ is composed of smaller grains, and the hardness of the HAZ is greater than that of the fusion zone. We discuss that the measured grain size and the hardness of the HAZ originate from undissolved precipitates that retard the grain growth of austenite.

  1. Mutagenicity of fume particles from metal arc welding on stainless steel in the Salmonella/microsome test.

    PubMed

    Maxild, J; Andersen, M; Kiel, P

    1978-01-01

    Mutagenic activity of fume particles produced by metal arc welding on stainless steel (ss) is demonstrated by using the Salmonella/microsome mutagenicity test described by Ames et al., with strain TA100 (base-pair substitution) and TA98 (frame-shift reversion). Results of a representative but limited selection of processes and materials show that mutagenic activity is a function of process and process parameters. Welding on stainless steel produces particles that are mutagenic, whereas welding on mild steel (ms) produces particles that are not. Manual metal arc (MMA) welding on stainless steel produces particles of higher mutagenic activity than does metal inert gas (MIG) welding, and fume particles produced by MIG welding under short-arc transfer. Further studies of welding fumes (both particles and gases) must be performed to determine process parameters of significance for the mutagenic activity.

  2. Process stability during fiber laser-arc hybrid welding of thick steel plates

    NASA Astrophysics Data System (ADS)

    Bunaziv, Ivan; Frostevarg, Jan; Akselsen, Odd M.; Kaplan, Alexander F. H.

    2018-03-01

    Thick steel plates are frequently used in shipbuilding, pipelines and other related heavy industries, and are usually joined by arc welding. Deep penetration laser-arc hybrid welding could increase productivity but has not been thoroughly investigated, and is therefore usually limited to applications with medium thickness (5-15 mm) sections. A major concern is process stability, especially when using modern welding consumables such as metal-cored wire and advanced welding equipment. High speed imaging allows direct observation of the process so that process behavior and phenomena can be studied. In this paper, 45 mm thick high strength steel was welded (butt joint double-sided) using the fiber laser-MAG hybrid process utilizing a metal-cored wire without pre-heating. Process stability was monitored under a wide range of welding parameters. It was found that the technique can be used successfully to weld thick sections with appropriate quality when the parameters are optimized. When comparing conventional pulsed and the more advanced cold metal transfer pulse (CMT+P) arc modes, it was found that both can provide high quality welds. CMT+P arc mode can provide more stable droplet transfer over a limited range of travel speeds. At higher travel speeds, an unstable metal transfer mechanism was observed. Comparing leading arc and trailing arc arrangements, the leading arc configuration can provide higher quality welds and more stable processing at longer inter-distances between the heat sources.

  3. Radioactively contaminated electric arc furnace dust as an addition to the immobilization mortar in low- and medium-activity repositories.

    PubMed

    Castellote, Marta; Menéndez, Esperanza; Andrade, Carmen; Zuloaga, Pablo; Navarro, Mariano; Ordóñez, Manuel

    2004-05-15

    Electric arc furnace dust (EAFD), generated by the steel-making industry, is in itself an intrinsic hazardous waste; however, the case may also be that scrap used in the process is accidentally contaminated by radioactive elements such as cesium. In this case the resulting EAFD is to be handled as radioactive waste, being duly confined in low- and medium-activity repositories (LMAR). What this paper studies is the reliability of using this radioactive EAFD as an addition in the immobilization mortar of the containers of the LMAR, that is, from the point of view of the durability. Different mixes of mortar containing different percentages of EAFD have been subjected to flexural and compressive strength, initial and final setting time, XRD study, total porosity and pore size distribution, determination of the chloride diffusion coefficient, dimensional stability tests, hydration heat, workability of the fresh mix, and leaching behavior. What is deduced from the results is that for the conditions used in this research, (cement + sand) can be replaced by EAFD upto a ratio [EAFD/(cement + EAFD)] of 46% in the immobilization mortar of LMAR, apparently without any loss in the long-term durability properties of the mortar.

  4. Surface martensitization of Carbon steel using Arc Plasma Sintering

    NASA Astrophysics Data System (ADS)

    Wahyudi, Haris; Dimyati, Arbi; Sebayang, Darwin

    2018-03-01

    In this paper new technology of surface structure modification of steel by short plasma exposure in Arc Plasma Sintering (APS) device is presented. APS is an apparatus working based on plasma generated by DC pulsed current originally used for synthesizing materials via sintering and melting. Plasma exposure in APS was applied into the specimens for 1 and 3 seconds which generate temperature approximately about 1300-1500°C. The SUP9, pearlitic carbon steel samples were used. The hardness, hardening depth and microstructure of the specimens have been investigated by Vickers micro hardness test and Scanning Electron Microscopy (SEM) supported by Energy Dispersive X-Ray Spectroscopy (EDX). The results have showed that the mechanical property was significantly improved due to the formation of single martensitic structures as identified by SEM. The hardness of treated surface evaluated by Vickers hardness test showed significant improvement nearly three time from 190 VHN before to 524 VHN after treatment. Furthermore, EDX confirmed that the formation of martensite layer occurred without altering its composition. The APS also produced uniform hardened layer up to 250 μm. The experiment has demonstrated that arc plasma process was successfully improved the mechanical properties of steel in relatively very short time.

  5. A combined arc-melting and tilt-casting furnace for the manufacture of high-purity bulk metallic glass materials.

    PubMed

    Soinila, E; Pihlajamäki, T; Bossuyt, S; Hänninen, H

    2011-07-01

    An arc-melting furnace which includes a tilt-casting facility was designed and built, for the purpose of producing bulk metallic glass specimens. Tilt-casting was chosen because reportedly, in combination with high-purity processing, it produces the best fatigue endurance in Zr-based bulk metallic glasses. Incorporating the alloying and casting facilities in a single piece of equipment reduces the amount of laboratory space and capital investment needed. Eliminating the sample transfer step from the production process also saves time and reduces sample contamination. This is important because the glass forming ability in many alloy systems, such as Zr-based glass-forming alloys, deteriorates rapidly with increasing oxygen content of the specimen. The challenge was to create a versatile instrument, in which high purity conditions can be maintained throughout the process, even when melting alloys with high affinity for oxygen. Therefore, the design provides a high-vacuum chamber to be filled with a low-oxygen inert atmosphere, and takes special care to keep the system hermetically sealed throughout the process. In particular, movements of the arc-melting electrode and sample manipulator arm are accommodated by deformable metal bellows, rather than sliding O-ring seals, and the whole furnace is tilted for tilt-casting. This performance of the furnace is demonstrated by alloying and casting Zr(55)Cu(30)Al(10)Ni(5) directly into rods up to ø 10 mm which are verified to be amorphous by x-ray diffraction and differential scanning calorimetry, and to exhibit locally ductile fracture at liquid nitrogen temperature.

  6. Improved Casting Furnace Conceptual Design

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fielding, Randall Sidney; Tolman, David Donald

    In an attempt to ensure more consistent casting results and remove some schedule variance associated with casting, an improved casting furnace concept has been developed. The improved furnace uses the existing arc melter hardware and glovebox utilities. The furnace concept was designed around physical and operational requirements such as; a charge sized of less than 30 grams, high heating rates and minimal additional footprint. The conceptual model is shown in the report as well as a summary of how the requirements were met.

  7. High temperature aircraft research furnace facilities

    NASA Technical Reports Server (NTRS)

    Smith, James E., Jr.; Cashon, John L.

    1992-01-01

    Focus is on the design, fabrication, and development of the High Temperature Aircraft Research Furnace Facilities (HTARFF). The HTARFF was developed to process electrically conductive materials with high melting points in a low gravity environment. The basic principle of operation is to accurately translate a high temperature arc-plasma gas front as it orbits around a cylindrical sample, thereby making it possible to precisely traverse the entire surface of a sample. The furnace utilizes the gas-tungsten-arc-welding (GTAW) process, also commonly referred to as Tungsten-Inert-Gas (TIG). The HTARFF was developed to further research efforts in the areas of directional solidification, float-zone processing, welding in a low-gravity environment, and segregation effects in metals. The furnace is intended for use aboard the NASA-JSC Reduced Gravity Program KC-135A Aircraft.

  8. Optimal Recycling of Steel Scrap and Alloying Elements: Input-Output based Linear Programming Method with Its Application to End-of-Life Vehicles in Japan.

    PubMed

    Ohno, Hajime; Matsubae, Kazuyo; Nakajima, Kenichi; Kondo, Yasushi; Nakamura, Shinichiro; Fukushima, Yasuhiro; Nagasaka, Tetsuya

    2017-11-21

    Importance of end-of-life vehicles (ELVs) as an urban mine is expected to grow, as more people in developing countries are experiencing increased standards of living, while the automobiles are increasingly made using high-quality materials to meet stricter environmental and safety requirements. While most materials in ELVs, particularly steel, have been recycled at high rates, quality issues have not been adequately addressed due to the complex use of automobile materials, leading to considerable losses of valuable alloying elements. This study highlights the maximal potential of quality-oriented recycling of ELV steel, by exploring the utilization methods of scrap, sorted by parts, to produce electric-arc-furnace-based crude alloy steel with minimal losses of alloying elements. Using linear programming on the case of Japanese economy in 2005, we found that adoption of parts-based scrap sorting could result in the recovery of around 94-98% of the alloying elements occurring in parts scrap (manganese, chromium, nickel, and molybdenum), which may replace 10% of the virgin sources in electric arc furnace-based crude alloy steel production.

  9. Wire-Arc-Sprayed Aluminum Protects Steel Against Corrosion

    NASA Technical Reports Server (NTRS)

    Zimmerman, Frank R.; Poorman, Richard; Sanders, Heather L.; Mckechnie, Timothy N.; Bonds, James W., Jr.; Daniel, Ronald L., Jr.

    1995-01-01

    Aluminum coatings wire-arc sprayed onto steel substrates found effective in protecting substrates against corrosion. Coatings also satisfy stringent requirements for adhesion and flexibility, both at room temperature and at temperatures as low as liquid hydrogen. Developed as alternatives to corrosion-inhibiting primers and paints required by law to be phased out because they contain and emit such toxic substances as chromium and volatile organic compounds.

  10. Method and Mechanisms of Soil Stabilization Using Electric Arc Furnace Dust

    PubMed Central

    Al-Amoudi, Omar S. Baghabra; Al-Homidy, Abdullah A.; Maslehuddin, Mohammed; Saleh, Tawfik A.

    2017-01-01

    This paper reports the method and mechanism for improving the strength of marl and desert sand utilizing electric arc furnace dust (EAFD), an industrial by-product, in lieu of cement or lime. EAFD was used in conjunction with a small quantity (2%) of cement. The mechanical properties and durability characteristics of marl and sand mixed with 2% cement plus 5-, 10-, 20- or 30%-EAFD, by weight of the soil, were evaluated. The soil-cement-EAFD mixtures were used to determine their unconfined compressive strength (UCS), soaked California Bearing Ratio (CBR) and durability. The risk of leaching of toxic heavy metals, such as lead and cadmium, from the stabilized soils to the groundwater was also investigated. The mechanisms of stabilization of the selected soils due to the use of EAFD along with a small quantity of cement are also elucidated. The usage of 20 to 30% EAFD with 2% cement was noted to considerably improve the mechanical properties and durability of both marl and sand. PMID:28452346

  11. Method and Mechanisms of Soil Stabilization Using Electric Arc Furnace Dust

    NASA Astrophysics Data System (ADS)

    Al-Amoudi, Omar S. Baghabra; Al-Homidy, Abdullah A.; Maslehuddin, Mohammed; Saleh, Tawfik A.

    2017-04-01

    This paper reports the method and mechanism for improving the strength of marl and desert sand utilizing electric arc furnace dust (EAFD), an industrial by-product, in lieu of cement or lime. EAFD was used in conjunction with a small quantity (2%) of cement. The mechanical properties and durability characteristics of marl and sand mixed with 2% cement plus 5-, 10-, 20- or 30%-EAFD, by weight of the soil, were evaluated. The soil-cement-EAFD mixtures were used to determine their unconfined compressive strength (UCS), soaked California Bearing Ratio (CBR) and durability. The risk of leaching of toxic heavy metals, such as lead and cadmium, from the stabilized soils to the groundwater was also investigated. The mechanisms of stabilization of the selected soils due to the use of EAFD along with a small quantity of cement are also elucidated. The usage of 20 to 30% EAFD with 2% cement was noted to considerably improve the mechanical properties and durability of both marl and sand.

  12. The efficacy of radiant heat controls on workers' heat stress around the blast furnace of a steel industry.

    PubMed

    Giahi, Omid; Darvishi, Ebrahim; Aliabadi, Mohsen; Khoubi, Jamshid

    2015-01-01

    Workers' exposure to excessive heat in molten industries is mainly due to radiant heat from hot sources. The aim of this study was to evaluate the efficacy of radiant heat controls on workers heat stress around a typical blast furnace. Two main interventions were applied for reducing radiant heat around the blast furnace of a steel industry located in western Iran. These included using a heat absorbing system in the furnace body and installing reflective aluminum barrier in the main workstation. Heat stress indexes were measured before and after each intervention using the digital WBGT-meter. The results showed MRT and WBGT indexes decreased by 20 °C and 3.9 °C, respectively after using heat absorbing system and also decreased by 18.6 °C and 2.5 °C, respectively after installing a reflective barrier. These indexes decrease by 26.5 °C and 5.2 °C, respectively due to the simultaneous application of the two interventions which were statistically significant (p < 0.001). The core body temperature of workers decreased by 2.6 °C after the application of interventions which was also significant (p < 0.05). The results confirmed heat control at source can be considered as a first solution for reducing radiant heat of blast furnaces. However, the simultaneous application of interventions could noticeably reduce worker heat stress. The results provide reliable information in order to implement the effective heat controls in typical hot steel industries.

  13. INTERIOR VIEW SHOWING QBOP FURNACE IN BLOW. OXYGEN AND NATURAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW SHOWING Q-BOP FURNACE IN BLOW. OXYGEN AND NATURAL GAS ARE BLOWN INTO THE FURNACE THROUGH THE TUYERES TO CHARGE 460,000 LBS. OF HOT METAL, 100,000 LBS. OF SCRAP WITH 30,000 LBS. OF LIME. BLOW TIME IS 16 MINUTES. THE TIME TO BLOW AND TAP THE FURNACES OF THE RESULTING 205,000 TONS OF STEEL AND SLAG IS 35 MINUTES. - U.S. Steel, Fairfield Works, Q-Bop Furnace, North of Valley Road & West of Ensley, Pleasant Grove Road, Fairfield, Jefferson County, AL

  14. Determination of silver in irons and steels by atomic-absorption spectrometry with an induction furnace: Direct analysis of solid samples.

    PubMed

    Aziz-Alrahman, A M; Headridge, J B

    1978-07-01

    The silver contents of 17 irons and steels have been determined by dropping 0.5-20mg of millings or turnings of the metals into an induction furnace situated within an atomic-absorption spectrophotometer. The limit of detection was 0.005 mug/g and the relative standard deviations were 12% or better for silver contents of not less than 0.05 mug/g. Samples are added to the furnace at 4-5 min intervals.

  15. Effects of shielding gas composition on arc profile and molten pool dynamics in gas metal arc welding of steels

    NASA Astrophysics Data System (ADS)

    Wang, L. L.; Lu, F. G.; Wang, H. P.; Murphy, A. B.; Tang, X. H.

    2014-11-01

    In gas metal arc welding, gases of different compositions are used to produce an arc plasma, which heats and melts the workpiece. They also protect the workpiece from the influence of the air during the welding process. This paper models gas metal arc welding (GMAW) processes using an in-house simulation code. It investigates the effects of the gas composition on the temperature distribution in the arc and on the molten pool dynamics in gas metal arc welding of steels. Pure argon, pure CO2 and different mixtures of argon and CO2 are considered in the study. The model is validated by comparing the calculated weld profiles with physical weld measurements. The numerical calculations reveal that gas composition greatly affects the arc temperature profile, heat transfer to the workpiece, and consequently the weld dimension. As the CO2 content in the shielding gas increases, a more constricted arc plasma with higher energy density is generated as a result of the increased current density in the arc centre and increased Lorentz force. The calculation also shows that the heat transferred from the arc to the workpiece increases with increasing CO2 content, resulting in a wider and deeper weld pool and decreased reinforcement height.

  16. 78 FR 13052 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-26

    ... Furnaces and Argon Oxygen Decarburization Vessels (Renewal) AGENCY: Environmental Protection Agency (EPA... www.regulations.gov . Title: NSPS for Steel Plants: Electric Arc Furnaces and Argon Oxygen.... Respondents/Affected Entities: Owners or operator of electric arc furnaces and argon oxygen decarburization...

  17. Tube furnace

    DOEpatents

    Foster, Kenneth G.; Frohwein, Eugene J.; Taylor, Robert W.; Bowen, David W.

    1991-01-01

    A vermiculite insulated tube furnace is heated by a helically-wound resistance wire positioned within a helical groove on the surface of a ceramic cylinder, that in turn is surroundingly disposed about a doubly slotted stainless steel cylindrical liner. For uniform heating, the pitch of the helix is of shorter length over the two end portions of the ceramic cylinder. The furnace is of large volume, provides uniform temperature, offers an extremely precise programmed heating capability, features very rapid cool-down, and has a modest electrical power requirement.

  18. Neutralization of cement-asbestos waste by melting in an arc-resistance furnace.

    PubMed

    Witek, Jerzy; Kusiorowski, Robert

    2017-11-01

    The paper presents the results of research on asbestos waste disposal by the melting process. The tests were carried out in a laboratory arc-resistance electric furnace. The obtained results showed that the fibrous structure of asbestos contained in cement-asbestos waste was completely destroyed. This led to the formation of new mineral phases without dangerous properties. The melting test was conducted on raw cement-asbestos samples without any additives and with a content of mineral compounds, the aim of which was to support the melting process. The additives were selected among others on the basis of the computer simulation results carried out using FactSage database computing system. The research results indicate that the melting process of asbestos wastes is a potential and interesting method of neutralizing hazardous asbestos waste, which allows for further treatment and material recycling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Ferrosilicon smelting in a direct current furnace

    DOEpatents

    Dosaj, V.D.; May, J.B.

    1992-12-29

    The present invention is a process for smelting ferrosilicon alloy. The process comprises adding a carbon source and tailings comprising oxides of silicon and iron to a substantially closed furnace. Heat is supplied to the furnace by striking a direct current arc between a cathode electrode and an anode functional hearth. In a preferred embodiment of the present invention, the cathode electrode is hollow and feed to the substantially closed furnace is through the hollow electrode. 1 figure.

  20. Ferrosilicon smelting in a direct current furnace

    DOEpatents

    Dosaj, Vishu D.; May, James B.

    1992-12-29

    The present invention is a process for smelting ferrosilicon alloy. The process comprises adding a carbon source and tailings comprising oxides of silicon and iron to a substantially closed furnace. Heat is supplied to the furnace by striking a direct current arc between a cathode electrode and an anode functional hearth. In a preferred embodiment of the present invention, the cathode electrode is hollow and feed to the substantially closed furnace is through the hollow electrode.

  1. [The electric furnace of Henri Moissan at one hundred years: connection with the electric furnace, the solar furnace, the plasma furnace?].

    PubMed

    Royère, C

    1999-03-01

    The trace of Henri Moissan's pioneer work 100 years ago is clearly evidenced by an overview of achievements in high temperature devices; 1987: "Le four électrique" by Henri Moissan; 1948-1952: "High temperature heating in a cavity rotary kiln using focusing of solar radiation" by Félix Trombe; 1962: "The cavity rotary kiln using focused solar radiation jointly with a plasma gun" by Marc Foëx; 1970: "The rotary kiln with two plasma guns and arc transfer" by Marc Foëx; 1984: "The plasma furnace" by Electricité de France (EDF) at Renardières; 1997: "The plasma furnace" by the Atomic Energy Center (CEA) at Cadarache, the VULCANO program. The first part of this contribution is devoted to Henri Moissan. Re-reading his early book on the electric furnace, especially the first chapter and the sections on silica, carbon vapor and experiments performed in casting molten metal--the conclusions are outstanding--provides modern readers with an amazing insight into future developments. The last two parts are devoted to Félix Trombe and Marc Foëx, tracing the evolution of high temperature cavity processus leading to the solar furnace and the present day plasma furnace at the CEA. Focus is placed on research conducted by the French National Center for Scientific Research (CNRS) with the solar and plasma furnaces at Odeillo. The relationships with Henri Moissan's early work are amazing, offering a well deserved homage to this pioneer researcher.

  2. The push for increased coal injection rates -- Blast furnace experience at AK Steel Corporation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dibert, W.A.; Duncan, J.H.; Keaton, D.E.

    1994-12-31

    An effort has been undertaken to increase the coal injection rate on Amanda blast furnace at AK Steel Corporation`s Ashland Works in Ashland, Kentucky to decrease fuel costs and reduce coke demand. Operating practices have been implemented to achieve a sustained coal injection rate of 140 kg/MT, increased from 100--110 kg/MT. In order to operate successfully at the 140 kg/MT injection rate; changes were implemented to the furnace charging practice, coal rate control methodology, orientation of the injection point, and the manner of distribution of coal to the multiple injection points. Additionally, changes were implemented in the coal processing facilitymore » to accommodate the higher demand of pulverized coal; grinding 29 tonnes per hour, increased from 25 tonnes per hour. Further increases in injection rate will require a supplemental supply of fuel.« less

  3. Baseline tests for arc melter vitrification of INEL buried wastes. Volume II: Baseline test data appendices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oden, L.L.; O`Conner, W.K.; Turner, P.C.

    1993-11-19

    This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc meltingmore » furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.« less

  4. Physics-Based Modeling of Electric Operation, Heat Transfer, and Scrap Melting in an AC Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Opitz, Florian; Treffinger, Peter

    2016-04-01

    Electric arc furnaces (EAF) are complex industrial plants whose actual behavior depends upon numerous factors. Due to its energy intensive operation, the EAF process has always been subject to optimization efforts. For these reasons, several models have been proposed in literature to analyze and predict different modes of operation. Most of these models focused on the processes inside the vessel itself. The present paper introduces a dynamic, physics-based model of a complete EAF plant which consists of the four subsystems vessel, electric system, electrode regulation, and off-gas system. Furthermore the solid phase is not treated to be homogenous but a simple spatial discretization is employed. Hence it is possible to simulate the energy input by electric arcs and fossil fuel burners depending on the state of the melting progress. The model is implemented in object-oriented, equation-based language Modelica. The simulation results are compared to literature data.

  5. 19. MOLTEN IRON FLOWS INTO A 'BOTTLE' AT FURNACE NO. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. MOLTEN IRON FLOWS INTO A 'BOTTLE' AT FURNACE NO. 1. THE IRON WILL BE TRANSPORTED BY RAIL TO THE OPEN HEARTH OR BASIC OXYGEN FURNACES, WHERE IT IS A MAJOR COMPONENT IN THE PRODUCTION OF STEEL. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  6. A New Method to Produce Ni-Cr Ferroalloy Used for Stainless Steel Production

    NASA Astrophysics Data System (ADS)

    Chen, Pei-Xian; Chu, Shao-Jun; Zhang, Guo-Hua

    2016-08-01

    A new electrosilicothermic method has been proposed in the present paper to produce Ni-Cr ferroalloy, which can be used for the production of 300 series stainless steel. Based on this new process, the Ni-Si ferroalloy is first produced as the intermediate alloy, and then the desiliconization process of Ni-Si ferroalloy melt with chromium concentrate is carried out to generate Ni-Cr ferroalloy. The silicon content in the Ni-Si ferroalloy produced in the submerged arc furnace should be more than 15 mass% (for the propose of reducing dephosphorization), in order to make sure the phosphorus content in the subsequently produced Ni-Cr ferroalloy is less than 0.03 mass%. A high utilization ratio of Si and a high recovery ratio of Cr can be obtained after the desiliconization reaction between Ni-Si ferroalloy and chromium concentrate in the electric arc furnace (EAF)-shaking ladle (SL) process.

  7. 40 CFR 63.10692 - What definitions apply to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... blown into molten steel for further refining. Capture system means the equipment (including ducts, hoods... furnace that produces molten steel and heats the charge materials with electric arcs from carbon... furnace (EAF) steelmaking facility means a steel plant that produces carbon, alloy, or specialty steels...

  8. 40 CFR 63.10692 - What definitions apply to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... blown into molten steel for further refining. Capture system means the equipment (including ducts, hoods... furnace that produces molten steel and heats the charge materials with electric arcs from carbon... furnace (EAF) steelmaking facility means a steel plant that produces carbon, alloy, or specialty steels...

  9. 40 CFR 63.10692 - What definitions apply to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... blown into molten steel for further refining. Capture system means the equipment (including ducts, hoods... furnace that produces molten steel and heats the charge materials with electric arcs from carbon... furnace (EAF) steelmaking facility means a steel plant that produces carbon, alloy, or specialty steels...

  10. Welding of Thin Steel Plates by Hybrid Welding Process Combined TIG Arc with YAG Laser

    NASA Astrophysics Data System (ADS)

    Kim, Taewon; Suga, Yasuo; Koike, Takashi

    TIG arc welding and laser welding are used widely in the world. However, these welding processes have some advantages and problems respectively. In order to improve problems and make use of advantages of the arc welding and the laser welding processes, hybrid welding process combined the TIG arc with the YAG laser was studied. Especially, the suitable welding conditions for thin steel plate welding were investigated to obtain sound weld with beautiful surface and back beads but without weld defects. As a result, it was confirmed that the shot position of the laser beam is very important to obtain sound welds in hybrid welding. Therefore, a new intelligent system to monitor the welding area using vision sensor is constructed. Furthermore, control system to shot the laser beam to a selected position in molten pool, which is formed by TIG arc, is constructed. As a result of welding experiments using these systems, it is confirmed that the hybrid welding process and the control system are effective on the stable welding of thin stainless steel plates.

  11. Elements of EAF automation processes

    NASA Astrophysics Data System (ADS)

    Ioana, A.; Constantin, N.; Dragna, E. C.

    2017-01-01

    Our article presents elements of Electric Arc Furnace (EAF) automation. So, we present and analyze detailed two automation schemes: the scheme of electrical EAF automation system; the scheme of thermic EAF automation system. The application results of these scheme of automation consists in: the sensitive reduction of specific consummation of electrical energy of Electric Arc Furnace, increasing the productivity of Electric Arc Furnace, increase the quality of the developed steel, increasing the durability of the building elements of Electric Arc Furnace.

  12. 2. EXTERIOR VIEW LOOKING SOUTHEAST AT ELECTRIC FURNACE BUILDING AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. EXTERIOR VIEW LOOKING SOUTHEAST AT ELECTRIC FURNACE BUILDING AND ELECTRIC FURNACE OFFICE & CHEMICAL LABORATORY BUILDING. INGOT MOLDS IN RIGHT FOREGROUND. - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  13. Effects of body formulation and firing temperature to properties of ceramic tile incorporated with electric arc furnace (EAF) slag waste

    NASA Astrophysics Data System (ADS)

    Sharif, Nurulakmal Mohd; Lim, Chi Yang; Teo, Pao Ter; Seman, Anasyida Abu

    2017-07-01

    Significant quantities of sludge and slag are generated as waste materials or by-products from steel industries. One of the by-products is Electric Arc Furnace (EAF) steel slag which consists of oxides such as CaO, Al2O3 and FeO. This makes it possible for slag to partially replace the raw materials in ceramic tile production. In our preliminary assessment of incorporating the EAF slag into ceramic tile, it was revealed that at fixed firing temperature of 1150°C, the tile of composition 40 wt.% EAF slag - 60 wt.% ball clay has comparable properties with commercial ceramic tile. Thus, this current study would focus on effects of body formulation (different weight percentages of K-feldspar and silica) and different firing temperatures to properties of EAF slag added ceramic tile. EAF slag from Southern Steel Berhad (SSB) was crushed into micron size (EAF slag content was 40 wt.%) and milled with ball clay, K-feldspar and silica before compacted and fired at 1125°C and 1150°C. The EAF slag added tile was characterized in terms of water absorption, apparent porosity, bulk density, modulus of rupture (MOR) and phase analysis via X-ray diffraction (XRD). The composition of 40 wt.% EAF slag - 30 wt.% ball clay - 10 wt.% K-feldspar - 20 wt.% silica (10F_20S), fired at 1150°C showed the lowest water absorption, apparent porosity and highest bulk density due to enhancement of densification process during firing. However, the same composition of ceramic tile (10F_20S) had the highest MOR at lower firing temperature of 1125°C, contributed by presence of the highest total amount of anorthite and wollastonite reinforcement crystalline phases (78.40 wt.%) in the tile. Overall, both the water absorption and MOR of all ceramic tiles surpassed the requirement regulated by MS ISO 13006:2014 Standard (Annex G: Dry-pressed ceramic tile with low water absorption, Eb ≤ 0.50 % and minimum MOR of 35 MPa).

  14. 40 CFR 63.7743 - How do I demonstrate continuous compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing... induction metal melting furnace or scrap preheater at a new iron and steel foundry, (i) Maintaining the... at or below 0.0004 gr/dscf. (2) For each cupola metal melting furnace at an existing iron and steel...

  15. 40 CFR 63.7743 - How do I demonstrate continuous compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing... induction metal melting furnace or scrap preheater at a new iron and steel foundry, (i) Maintaining the... at or below 0.0004 gr/dscf. (2) For each cupola metal melting furnace at an existing iron and steel...

  16. 40 CFR 63.7743 - How do I demonstrate continuous compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing... induction metal melting furnace or scrap preheater at a new iron and steel foundry, (i) Maintaining the... at or below 0.0004 gr/dscf. (2) For each cupola metal melting furnace at an existing iron and steel...

  17. 40 CFR 63.7743 - How do I demonstrate continuous compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing... induction metal melting furnace or scrap preheater at a new iron and steel foundry, (i) Maintaining the... at or below 0.0004 gr/dscf. (2) For each cupola metal melting furnace at an existing iron and steel...

  18. Baseline tests for arc melter vitrification of INEL buried wastes. Volume 1: Facility description and summary data report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oden, L.L.; O`Connor, W.K.; Turner, P.C.

    1993-11-19

    This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc meltingmore » furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.« less

  19. Erosion resistance of arc-sprayed coatings to iron ore at 25 and 315 °C

    NASA Astrophysics Data System (ADS)

    Dallaire, S.; Levert, H.; Legoux, J.-G.

    2001-06-01

    Iron ore pellets are sintered and reduced in large continuous industrial oil-fired furnaces. From the furnace, powerful fans extract large volumes of hot gas. Being exposed to gas-borne iron ore particles and temperatures ranging between 125 and 328 °C, fan components are rapidly eroded. Extensive part repair or replacement is required for maintaining a profitable operation. The arc spraying technique has been suggested for repair provided it could produce erosion-resistant coatings. Conventional and cored wires (1.6 mm diameter) were arc sprayed using various spray parameters to produce 250 to 300 µm thick coatings. Arc-sprayed coatings and reference specimens were erosion tested at 25 and 315 °C and impact angles of 25 and 90° in a laboratory gas-blast erosion rig. This device was designed to impact materials with coarse (32 to 300 µm) iron ore particles at a speed of 100 m/s. The coating volume loss due to erosion was measured with a laser profilometer built by National Research Council Canada several years ago. Few arc-sprayed coatings exhibited erosion resistance comparable with structural steel at low impact angles. Erosion of arc-sprayed coatings and reference specimens dramatically increases at 315 °C for both 25° and 90° impact angles. Erosion-enhanced oxidation was found to be responsible for the increase in volume loss above room temperature. Though arc spraying can be appropriate for on-site repair, the development of more erosion-resistant coatings is required for intermediate temperatures.

  20. 40 CFR 420.41 - Specialized definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) [Reserved] (c) The term electric arc furnace steelmaking means the production of steel principally from steel scrap and fluxes in refractory lined furnaces by passing an electric current through the scrap or...

  1. 40 CFR 420.41 - Specialized definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... adding oxygen. (b) [Reserved] (c) The term electric arc furnace steelmaking means the production of steel principally from steel scrap and fluxes in refractory lined furnaces by passing an electric current through...

  2. 40 CFR 420.41 - Specialized definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) [Reserved] (c) The term electric arc furnace steelmaking means the production of steel principally from steel scrap and fluxes in refractory lined furnaces by passing an electric current through the scrap or...

  3. 40 CFR 420.41 - Specialized definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) [Reserved] (c) The term electric arc furnace steelmaking means the production of steel principally from steel scrap and fluxes in refractory lined furnaces by passing an electric current through the scrap or...

  4. Interfacial microstructure and properties of copper clad steel produced using friction stir welding versus gas metal arc welding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Z.; Chen, Y.; Haghshenas, M., E-mail: mhaghshe@uwaterloo.ca

    A preliminary study compares the feasibility and microstructures of pure copper claddings produced on a pressure vessel A516 Gr. 70 steel plate, using friction stir welding versus gas metal arc welding. A combination of optical and scanning electron microscopy is used to characterize the grain structures in both the copper cladding and heat affected zone in the steel near the fusion line. The friction stir welding technique produces copper cladding with a grain size of around 25 μm, and no evidence of liquid copper penetration into the steel. The gas metal arc welding of copper cladding exhibits grain sizes overmore » 1 mm, and with surface microcracks as well as penetration of liquid copper up to 50 μm into the steel substrate. Transmission electron microscopy reveals that metallurgical bonding is produced in both processes. Increased diffusion of Mn and Si into the copper cladding occurs when using gas metal arc welding, although some nano-pores were detected in the FSW joint interface. - Highlights: • Cladding of steel with pure copper is possible using either FSW or GMAW. • The FSW yielded a finer grain structure in the copper, with no evidence of cracking. • The FSW joint contains some evidence of nano-pores at the interface of the steel/copper. • Copper cladding by GMAW contained surface cracks attributed to high thermal stresses. • The steel adjacent to the fusion line maintained a hardness value below 248 HV.« less

  5. 5. Photocopied August 1978. FRONT OF A HORRY ROTARY FURNACE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Photocopied August 1978. FRONT OF A HORRY ROTARY FURNACE, SHOWING INTERIOR ELECTRODES. THE RAW MATERIALS FOR CALCIUM CARBIDE PRODUCTION--LIMESTONE AND COKE--WERE FED BY HOPPERS PLACED BETWEEN THESE ELECTRODES INTO THE ELECTRIC ARC. THE REMOVABLE PLATES ON THE EXTERNAL CIRCUMSTANCE OF THE HORRY FURNACE ARE SHOWN ON THE FIRST THREE FURNACES. (M) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  6. Time series prediction in the case of nonlinear loads by using ADALINE and NAR neural networks

    NASA Astrophysics Data System (ADS)

    Ghiormez, L.; Panoiu, M.; Panoiu, C.; Tirian, O.

    2018-01-01

    This paper presents a study regarding the time series prediction in the case of an electric arc furnace. The considered furnace is a three phase load and it is used to melt scrap in order to obtain liquid steel. The furnace is powered by a three-phase electrical supply and therefore has three graphite electrodes. The furnace is a nonlinear load that can influence the equipment connected to the same electrical power supply network. The nonlinearity is given by the electric arc that appears at the furnace between the graphite electrode and the scrap. Because of the disturbances caused by the electric arc furnace during the elaboration process of steel it is very useful to predict the current of the electric arc and the voltage from the measuring point in the secondary side of the furnace transformer. In order to make the predictions were used ADALINE and NAR neural networks. To train the networks and to make the predictions were used data acquired from the real technological plant.

  7. Use of computer systems and process information for blast furnace operations at U. S. Steel, Gary Works

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sherman, G.J.; Zmierski, M.L.

    1994-09-01

    US Steel Iron Producing Div. consists of four operating blast furnaces ranging in process control capabilities from 1950's and 1960's era hardware to state of the art technology. The oldest control system consists of a large number of panels containing numerous relays, indicating lights, selector switches, push buttons, analog controllers, strip chart recorders and annunciators. In contrast, the state of the art control system utilizes remote I/O, two sets of redundant PLC's, redundant charge director computer, redundant distributed control system, high resolution video-graphic display system and supervisory computer for real-time data acquisition. Process data are collected and archived on twomore » DEC VAX computers, one for No. 13 blast furnace and the other for the three south end furnaces. Historical trending, data analysis and reporting are available to iron producing personnel through terminals and PC's connected directly to the systems, dial-up modems and various network configurations. These two machines are part of the iron producing network which allows them to pass and receive information from each other as well as numerous other sources throughout the division. This configuration allows personnel to access most pertinent furnace information from a single source. The basic objective of the control systems is to charge raw materials to the top of the furnace at aim weights and sequence, while maintaining blast conditions at the bottom of the furnace at required temperature, pressure and composition. Control changes by the operators are primarily supervisory based on review of system generated plots and tables.« less

  8. 57. GENERAL VIEW OF FURNACES No. 3 AND No. 4 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    57. GENERAL VIEW OF FURNACES No. 3 AND No. 4 TO THE LEFT OF THE FURNACES IS THE ORE BRIDGE, THE TURBO-GENERATOR BUILDING, AND THE WATER FILTER TANKS. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  9. 56. GENERAL VIEW OF FURNACES No. 3 AND No. 4 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    56. GENERAL VIEW OF FURNACES No. 3 AND No. 4 TO THE LEFT OF THE FURNACES IS THE ORE BRIDGE, THE TURBO-GENERATOR BUILDING, AND THE WATER FILTER TANKS. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  10. Driven motion and instability of an atmospheric pressure arc

    NASA Astrophysics Data System (ADS)

    Karasik, Max

    Atmospheric pressure arcs are used extensively in applications such as welding and metallurgy. However, comparatively little is known of the physics of such arcs in external magnetic fields and the mechanisms of the instabilities present. In order to address questions of equilibrium and stability of such arcs, an experimental are furnace is constructed and operated in air with graphite cathode and steel anode at currents 100--250 A. The arc is diagnosed with a gated intensified camera and a collimated photodiode array, as well as fast voltage and current probes. Experiments are carried out on the response of the are to applied transverse DC and AC (up to ≈1 kHz) magnetic fields. The arc is found to deflect parabolically for DC field and assumes a growing sinusoidal structure for AC field. A simple analytic two-parameter fluid model of the are dynamics is derived, in which the inertia of the magnetically pumped cathode jet balances the applied J⃗xB⃗ force. Time variation of the applied field allows evaluation of the parameters individually. A fit of the model to the experimental data gives a value for the average jet speed an order of magnitude below Maecker's estimate of the maximum jet speed. A spontaneous instability of the same arc is investigated experimentally and modeled analytically. The presence of the instability is found to depend critically on cathode dimensions. For cylindrical cathodes, instability occurs only for a narrow range of cathode diameters. Cathode spot motion is proposed as the mechanism of the instability. A simple fluid model combining the effect of the cathode spot motion and the inertia of the cathode jet successfully describes the arc shape during low amplitude instability. The amplitude of cathode spot motion required by the model is in agreement with measurements. The average jet velocity required is approximately equal to that inferred from the transverse magnetic field experiments. Reasons for spot motion and for cathode

  11. Microstructure and corrosion behavior of shielded metal arc-welded dissimilar joints comprising duplex stainless steel and low alloy steel

    NASA Astrophysics Data System (ADS)

    Srinivasan, P. Bala; Muthupandi, V.; Sivan, V.; Srinivasan, P. Bala; Dietzel, W.

    2006-12-01

    This work describes the results of an investigation on a dissimilar weld joint comprising a boiler-grade low alloy steel and duplex stainless steel (DSS). Welds produced by shielded metal arc-welding with two different electrodes (an austenitic and a duplex grade) were examined for their microstructural features and properties. The welds were found to have overmatching mechanical properties. Although the general corrosion resistance of the weld metals was good, their pitting resistance was found to be inferior when compared with the DSS base material.

  12. 1. GENERAL EXTERIOR VIEW OF THE ELECTRIC FURNACE STEELMAKING PLANT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL EXTERIOR VIEW OF THE ELECTRIC FURNACE STEELMAKING PLANT LOOKING NORTHEAST. - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  13. Products of steel slags an opportunity to save natural resources.

    PubMed

    Motz, H; Geiseler, J

    2001-01-01

    In Germany, and in the most industrial countries, the use of blast furnace and steel slags as an aggregate for civil engineering, for metallurgical use and as fertiliser has a very long tradition. Since the introduction of the basic oxygen steel making furnace (BOF) process and the electric arc furnace (EAF) process the German steel industry started extensive research on the development of fields of application for BOF and EAF slags. These investigations have been mainly performed by Forschungsgemeinschaft Eisenhüttenschlacken e. V. (FEhS), the Research Association for blast furnace and steel slags. Today steel slags are well characterised and long-term experienced materials mainly used as aggregates for road construction (e.g. asphaltic or unbound layers), as armour-stones for hydraulic engineering constructions (e.g. stabilisation of shores), and as fertiliser for agriculture purposes. These multifarious fields of application could only be achieved because the steelworks influence the quality of slags by a careful selection of raw materials and a suitable process route. Furthermore, subsequent procedures like a treatment of the liquid slag, an appropriate heat treatment and a suitable processing have been developed to ensure that the quality of steel slags is always adequate for the end use. Depending on the respective field of application, the suitability of steel slags has to be proven by determining the technical properties, as well as the environmental compatibility. For this reason test methods have been developed to evaluate the technical properties especially the volume stability and the environmental behaviour. To evaluate the volume stability a suitable test (steam test) has been developed and the results from laboratory tests were compared with the behaviour of steel slags under practical conditions, e.g. in a road. To determine the environmental behaviour leaching tests have been developed. In the meanwhile most of these test methods are drafted or

  14. Hazard of ultraviolet radiation emitted in gas metal arc welding of mild steel.

    PubMed

    Nakashima, Hitoshi; Utsunomiya, Akihiro; Takahashi, Jyunya; Fujii, Nobuyuki; Okuno, Tsutomu

    2016-09-30

    Ultraviolet radiation (UVR) emitted during arc welding frequently causes keratoconjunctivitis and erythema in the workplace. The degree of hazard from UVR exposure depends on the welding method and conditions. Therefore, it is important to identify the UVR levels present under various conditions. We experimentally evaluated the UVR levels emitted in gas metal arc welding (GMAW) of mild steel. We used both a pulsed welding current and a non-pulsed welding current. The shielding gases were 80% Ar + 20% CO 2 and 100% CO 2 . The effective irradiance defined in the American Conference of Governmental Industrial Hygienists guidelines was used to quantify the UVR hazard. The effective irradiance measured in this study was in the range of 0.51-12.9 mW/cm 2 at a distance of 500 mm from the arc. The maximum allowable exposure times at these levels are only 0.23-5.9 s/day. The following conclusions were made regarding the degree of hazard from UVR exposure during the GMAW of mild steel: (1) It is more hazardous at higher welding currents than at lower welding currents. (2) At higher welding currents, it is more hazardous when 80% Ar + 20% CO 2 is used as a shielding gas than when 100% CO 2 is used. (3) It is more hazardous for pulsed welding currents than for non-pulsed welding currents. (4) It appears to be very hazardous when metal transfer is the spray type. This study demonstrates that unprotected exposure to UVR emitted by the GMAW of mild steel is quite hazardous.

  15. Hazard of ultraviolet radiation emitted in gas metal arc welding of mild steel

    PubMed Central

    Nakashima, Hitoshi; Utsunomiya, Akihiro; Takahashi, Jyunya; Fujii, Nobuyuki; Okuno, Tsutomu

    2016-01-01

    Objectives: Ultraviolet radiation (UVR) emitted during arc welding frequently causes keratoconjunctivitis and erythema in the workplace. The degree of hazard from UVR exposure depends on the welding method and conditions. Therefore, it is important to identify the UVR levels present under various conditions. Methods: We experimentally evaluated the UVR levels emitted in gas metal arc welding (GMAW) of mild steel. We used both a pulsed welding current and a non-pulsed welding current. The shielding gases were 80% Ar + 20% CO2 and 100% CO2. The effective irradiance defined in the American Conference of Governmental Industrial Hygienists guidelines was used to quantify the UVR hazard. Results: The effective irradiance measured in this study was in the range of 0.51-12.9 mW/cm2 at a distance of 500 mm from the arc. The maximum allowable exposure times at these levels are only 0.23-5.9 s/day. Conclusions: The following conclusions were made regarding the degree of hazard from UVR exposure during the GMAW of mild steel: (1) It is more hazardous at higher welding currents than at lower welding currents. (2) At higher welding currents, it is more hazardous when 80% Ar + 20% CO2 is used as a shielding gas than when 100% CO2 is used. (3) It is more hazardous for pulsed welding currents than for non-pulsed welding currents. (4) It appears to be very hazardous when metal transfer is the spray type. This study demonstrates that unprotected exposure to UVR emitted by the GMAW of mild steel is quite hazardous. PMID:27488036

  16. A possible recycling method for high grade steels EAFD in polymer composites.

    PubMed

    Niubó, M; Fernández, A I; Chimenos, J M; Haurie, L

    2009-11-15

    This work evaluates the feasibility of incorporating electric arc furnace dust (EAFD), as filler in a polymer matrix, to obtain a moldable heavyweight sheet, useful for acoustic insulation in automotive industry. For this purpose EAFD from a steel factory that manufactures high quality steels, was characterized and different formulations of composites were prepared. Physical and mechanical properties, as well as fire behaviour were tested and compared with a polymer composite compounded with common mineral fillers. Optimum formulation with 25% EAFD fulfils the RoHs Directive used by automotive industry to regulate heavy metals content. Leaching test was also performed on prepared composites to classify the material after use.

  17. 6. GENERAL VIEW OF FURNACES No. 3 AND No. 4 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. GENERAL VIEW OF FURNACES No. 3 AND No. 4 TO THE LEFT OF THE FURNACES ARE THE ORE BRIDGE, THE TURBO-GENERATOR BUILDING, AND THE WATER FILTER TANKS. Jet Lowe, Photographer, 1989. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  18. Dissimilar Arc Welding of Advanced High-Strength Car-Body Steel Sheets

    NASA Astrophysics Data System (ADS)

    Russo Spena, P.; D'Aiuto, F.; Matteis, P.; Scavino, G.

    2014-11-01

    A widespread usage of new advanced TWIP steel grades for the fabrication of car-body parts is conditional on the employment of appropriate welding methods, especially if dissimilar welding must be performed with other automotive steel grades. Therefore, the microstructural features and the mechanical response of dissimilar butt weld seams of TWIP and 22MnB5 steel sheets after metal-active-gas arc welding are examined. The microstructural and mechanical characterization of the welded joints was carried out by optical metallography, microhardness and tensile testing, and fractographic examination. The heat-affected zone on the TWIP side was fully austenitic and the only detectable effect was grain coarsening, while on the 22MnB5 side it exhibited newly formed martensite and tempered martensite. The welded tensile specimens exhibited a much larger deformation on the TWIP steel side than on the 22MnB5. The fracture generally occurred at the interface between the fusion zone and the heat-affected zones, with the fractures surfaces being predominantly ductile. The ultimate tensile strength of the butt joints was about 25% lower than that of the TWIP steel.

  19. Enhanced humification by carbonated basic oxygen furnace steel slag--I. Characterization of humic-like acids produced from humic precursors.

    PubMed

    Qi, Guangxia; Yue, Dongbei; Fukushima, Masami; Fukuchi, Shigeki; Nie, Yongfeng

    2012-01-01

    Carbonated basic oxygen furnace steel slag (hereinafter referred to as "steel slag") is generated during iron and steel manufacturing and is often classified as waste. The effect of steel slag on humification process was investigated. Catechol, glycine and glucose were used as model humic precursors from degraded biowastes. To verify that humification occurred in the system, humic-like acids (HLAs) were isolated and characterized structurally by elemental analysis, FTIR spectra, solid-state CP-MAS (13)C NMR spectra, and TMAH-Py-GC/MS. Characteristics of the steel slag-HLA were compared with those of HLAs formed in the presence of zeolite and birnessite, and with that of mature compost humic acid. The results showed that steel slag-HLA, like zeolite- and birnessite-HLA, is complex organic material containing prominent aromatic structures. Steel slag substantially accelerated the humification process, which would be highly significant for accelerating the stabilization of biowastes during composting (e.g. municipal solid waste, sewage sludge, and food waste). Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Structural ceramics containing electric arc furnace dust.

    PubMed

    Stathopoulos, V N; Papandreou, A; Kanellopoulou, D; Stournaras, C J

    2013-11-15

    In the present work the stabilization of electric arc furnace dust EAFD waste in structural clay ceramics was investigated. EAFD was collected over eleven production days. The collected waste was characterized for its chemical composition by Flame Atomic Absorption Spectroscopy. By powder XRD the crystal structure was studied while the fineness of the material was determined by a laser particle size analyzer. The environmental characterization was carried out by testing the dust according to EN12457 standard. Zn, Pb and Cd were leaching from the sample in significant amounts. The objective of this study is to investigate the stabilization properties of EAFD/clay ceramic structures and the potential of EAFD utilization into structural ceramics production (blocks). Mixtures of clay with 2.5% and 5% EAFD content were studied by TG/DTA, XRD, SEM, EN12457 standard leaching and mechanical properties as a function of firing temperature at 850, 900 and 950 °C. All laboratory facilities maintained 20 ± 1 °C. Consequently, a pilot-scale experiment was conducted with an addition of 2.5% and 5% EAFD to the extrusion mixture for the production of blocks. During blocks manufacturing, the firing step reached 950 °C in a tunnel kiln. Laboratory heating/cooling gradients were similar to pilot scale production firing. The as produced blocks were then subjected to quality control tests, i.e. dimensions according to EN772-17, water absorbance according to EN772-6, and compressive strength according to EN772-1 standard, in laboratory facilities certified under EN17025. The data obtained showed that the incorporation of EAFD resulted in an increase of mechanical strength. Moreover, leaching tests performed according to the Europeans standards on the EAFD-block samples showed that the quantities of heavy metals leached from crushed blocks were within the regulatory limits. Thus the EAFD-blocks can be regarded as material of no environmental concern. Copyright © 2013 Elsevier B

  1. Sulphated Electric Arc Furnace Slag Asfenton-Like Catalyst for Degradation of Reactive Black 5

    NASA Astrophysics Data System (ADS)

    Zubir, N. A.; Nasuha, N.; Alrozi, R.

    2018-06-01

    Sulphated electric arc furnace slag (S-EAFS) was obtained through a facile chemical and thermal treatment method. The S-EAFS was evaluated as a Fenton-like catalyst for the oxidative degradation of reactive black 5 (RB5). The S-EAFS was characterized by XRD, SEM-EDX and nitrogen adsorption analysis. The highest RB5 degradation efficiency obtained in this study was above 90% which was maintained across seven successive cycles with minimum iron leaching. This was achieved at a RB5 concentration of 0.15 gL-1 (50 ppm) with 8 mM of H2O2 and a pH of 4.5. Characterization revealed that the presence of sulphated groups (SO4 2-) within the EAFS improved the surface acidity of the material and corresponded to an increase in the catalytic activity for the degradation of RB5 at mild pH.

  2. 42. Casting floor, "B" furnace, pour in progress; mudgun is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. Casting floor, "B" furnace, pour in progress; mudgun is to right of furnace; operator takes temperature of iron in trough during pout. Looking south - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  3. INTERIOR VIEW WITH LADLE POURING MOLTEN IRON INTO QBOP FURNACE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH LADLE POURING MOLTEN IRON INTO Q-BOP FURNACE. - U.S. Steel, Fairfield Works, Q-Bop Furnace, North of Valley Road & West of Ensley, Pleasant Grove Road, Fairfield, Jefferson County, AL

  4. 52. Winch located at base of No. 1 Furnace for ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    52. Winch located at base of No. 1 Furnace for pulling ladle cars from furnace to pig machine. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  5. Brazing open cell reticulated copper foam to stainless steel tubing with vacuum furnace brazed gold/indium alloy plating

    DOEpatents

    Howard, Stanley R [Windsor, SC; Korinko, Paul S [Aiken, SC

    2008-05-27

    A method of fabricating a heat exchanger includes brush electroplating plated layers for a brazing alloy onto a stainless steel tube in thin layers, over a nickel strike having a 1.3 .mu.m thickness. The resultant Au-18 In composition may be applied as a first layer of indium, 1.47 .mu.m thick, and a second layer of gold, 2.54 .mu.m thick. The order of plating helps control brazing erosion. Excessive amounts of brazing material are avoided by controlling the electroplating process. The reticulated copper foam rings are interference fit to the stainless steel tube, and in contact with the plated layers. The copper foam rings, the plated layers for brazing alloy, and the stainless steel tube are heated and cooled in a vacuum furnace at controlled rates, forming a bond of the copper foam rings to the stainless steel tube that improves heat transfer between the tube and the copper foam.

  6. Heavy metal adsorption changes of EAF steel slag after phosphorus adsorption.

    PubMed

    Song, Guanling; Cao, Lijing; Chen, Xiao; Hou, Wenhua; Wang, Qunhui

    2012-01-01

    A kind of electric arc furnace (EAF) steel slag was phosphated, and its isothermal and dynamic adsorptions of copper, cadmium, and lead ions were measured to determine if heavy metal adsorption changes after phosphorus adsorption. The surface area increased greatly after the slag was phosphated. Isothermal adsorption experiments showed that the theoretical Q(max) of the EAF steel slag on Cu(2+), Cd(2+), and Pb(2+) improved 59, 50, and 89% respectively after it was phosphated. Dynamic adsorption results showed that the greatest adsorption capacities of unit volume of Cu(2+), Cd(2+), and Pb(2+) were 2.2, 1.8, and 1.8 times that of the column packed with original EAF steel slag when the column was packed with phosphate EAF steel slag at the same heavy metal ion concentration. The breakthrough time, the exhaustion time and elution efficiency of the column also increased when the column was packed with phosphated EAF steel slag compared with that packed with original EAF steel slag. Phosphorus adsorption could further improve the heavy metal ion adsorption of the EAF steel slag.

  7. 4. LOOKING SOUTHEAST INSIDE OF ELECTRIC FURNACE BUILDING ON GROUND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. LOOKING SOUTHEAST INSIDE OF ELECTRIC FURNACE BUILDING ON GROUND FLOOR OF CHARGING AISLE. VIEW OF 50 TON CAPACITY CHARGING BUCKET. - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  8. 12. SOUTHWEST VIEW OF BASIC OXYGEN FURNACE No. 2 ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. SOUTHWEST VIEW OF BASIC OXYGEN FURNACE No. 2 ON THE OPERATING FLOOR OF THE FURNACE AISLE IN THE BOP SHOP - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  9. 3. INSIDE BATCH FURNACE BUILDING, VIEW LOOKING NORTH AT REGENERATIVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. INSIDE BATCH FURNACE BUILDING, VIEW LOOKING NORTH AT REGENERATIVE BATCH FURNACES ON LEFT AND 5 TON CAPACITY CHARGING MACHINE ON RIGHT. - U.S. Steel Duquesne Works, 22-Inch Bar Mill, Along Monongahela River, Duquesne, Allegheny County, PA

  10. 4. CLOSEUP VIEW INTO A REHEATING FURNACE IN THE No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. CLOSE-UP VIEW INTO A REHEATING FURNACE IN THE No. 2 FORGE SHOP. THE FURNACE IS MISSING ITS REFRACTORY BRICK LINING. - U.S. Steel Homestead Works, Press Shop No. 2, Along Monongahela River, Homestead, Allegheny County, PA

  11. 3. LOOKING WEST INSIDE ELECTRIC FURNACE BUILDING ON CHARGING FLOOR. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. LOOKING WEST INSIDE ELECTRIC FURNACE BUILDING ON CHARGING FLOOR. VIEW OF 7 1/2 TON CAPACITY ALLIANCE SIDE DOOR CHARGING MACHINE. - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  12. 14. WESTERN VIEW OF INVERTED BASIC OXYGEN FURNACE No. 1 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. WESTERN VIEW OF INVERTED BASIC OXYGEN FURNACE No. 1 ON THE OPERATING FLOOR OF THE FURNACE AISLE IN THE BOP SHOP. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  13. 15. WESTERN VIEW OF INVERTED BASIC OXYGEN FURNACE No. 2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. WESTERN VIEW OF INVERTED BASIC OXYGEN FURNACE No. 2 ON THE GROUND FLOOR OF THE FURNACE AISLE IN THE BOP SHOP. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  14. 13. WESTERN VIEW OF INVERTED BASIC OXYGEN FURNACE No. 2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. WESTERN VIEW OF INVERTED BASIC OXYGEN FURNACE No. 2 ON THE OPERATING FLOOR OF THE FURNACE AISLE IN THE BOP SHOP. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  15. Research regarding the vacuuming of liquid steel on steel degassing

    NASA Astrophysics Data System (ADS)

    Magaon, M.; Radu, M.; Şerban, S.; Zgripcea, L.

    2018-01-01

    When the liquid steel comes in contact with the atmosphere of the elaboration aggregates, a process of gas diffusion into the metal bath takes place on the one hand, and on the other hand a process that allows them to pass from the metal bath into the atmosphere. The meaning of these processes is determined by a number of factors as follows: the quality of raw and auxiliary materials (moisture content, oils, etc.), the boiling intensity, the evacuation duration, the properties of used slags, the values of the casting ladle processing parameters (bubbling, vacuuming, etc.). The research was carried out at an electrical steelwork, equipped with an electric arc furnace type EBT (Electric Bottom Tapping) capacity 100t, LF (Ladle-Furnace) and VD (Vacuum Degassing) facilities, establishing some correlations between the vacuuming parameters from the V.D.facility and the amounts of hydrogen and nitrogen removed from the metal bath, as well as their removal efficiency, were taken into consideration. The obtained data was processed in MATLAB calculation program, the established correlations form was presented both in analytical and graphical form. The validity of these correlations was verified in practice, being particularly useful in research.

  16. 5. LOOKING SOUTHWEST INSIDE OF ELECTRIC FURNACE BUILDING ON GROUND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. LOOKING SOUTHWEST INSIDE OF ELECTRIC FURNACE BUILDING ON GROUND FLOOR OF POURING AISLE. VIEW OF THE NATION'S FIRST VACUUM DEGASSING UNIT (1956). - U.S. Steel Duquesne Works, Electric Furnace Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  17. 22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL CONSTRUCTION. CONCRETE PAD AT LEFT IS SITE OF FORMER FURNACE USED TO HEAT URANIUM BILLETS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  18. 11. SOUTHWEST VIEW OF BASIC OXYGEN FURNACES No. 1 AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. SOUTHWEST VIEW OF BASIC OXYGEN FURNACES No. 1 AND No. 2 ON THE OPERATING FLOOR OF THE FURNACE AISLE IN THE BOP SHOP - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  19. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of MIL A46100 Armor-Grade Steel: A Computational Investigation

    DTIC Science & Technology

    2014-06-12

    distribution is unlimited. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel : A Computational Investigation The views...Welds of Mil A46100 Armor-Grade Steel : A Computational Investigation Report Title In our recent work, a multi-physics computational model for the...introduction of the sixth module in the present work in recognition of the fact that in thick steel GMAW weldments, the overall ballistic performance

  20. Minimization of Blast furnace Fuel Rate by Optimizing Burden and Gas Distribution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dr. Chenn Zhou

    2012-08-15

    The goal of the research is to improve the competitive edge of steel mills by using the advanced CFD technology to optimize the gas and burden distributions inside a blast furnace for achieving the best gas utilization. A state-of-the-art 3-D CFD model has been developed for simulating the gas distribution inside a blast furnace at given burden conditions, burden distribution and blast parameters. The comprehensive 3-D CFD model has been validated by plant measurement data from an actual blast furnace. Validation of the sub-models is also achieved. The user friendly software package named Blast Furnace Shaft Simulator (BFSS) has beenmore » developed to simulate the blast furnace shaft process. The research has significant benefits to the steel industry with high productivity, low energy consumption, and improved environment.« less

  1. DETAIL VIEW OF THE BASE OF THE BLAST FURNACE, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF THE BASE OF THE BLAST FURNACE, SHOWING THE BUSTLE PIPE ENCIRCLING THE FURNACE (ABOVE) AND THE TAP HOLE IN TILE CENTER OF THE PHOTOGRAPH. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  2. INTERIOR VIEW WITH SCRAP HAULER DUMPING SCRAP INTO QBOP FURNACE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH SCRAP HAULER DUMPING SCRAP INTO Q-BOP FURNACE. SCRAP HAULER IS GREGORY JACKS. FURNACEMAN IS VINCENT MOREL. - U.S. Steel, Fairfield Works, Q-Bop Furnace, North of Valley Road & West of Ensley, Pleasant Grove Road, Fairfield, Jefferson County, AL

  3. Looking east at the basic oxygen furnace building with gas ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking east at the basic oxygen furnace building with gas cleaning plants in foreground on the left and the right side of the furnace building. - U.S. Steel Edgar Thomson Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Braddock, Allegheny County, PA

  4. Properties of the welded joints of manganese steel made by low-frequency pulsed arc welding

    NASA Astrophysics Data System (ADS)

    Saraev, Yu. N.; Bezborodov, V. P.; Gladovskii, S. V.; Golikov, N. I.

    2017-04-01

    The structure, the mechanical properties, the impact toughness, and the fracture mechanisms of the welded joints made of steel 09G2S plates by direct current welding and pulsed arc welding with a modulated arc current in the frequency range 0.25-5.0 Hz are studied. The application of low-frequency pulsed arc welding allowed us to form welded joints with a fine-grained structure in the weld metal and the heat-affected zone and to achieve a higher impact toughness and a longer cyclic fatigue life as compared to the welded joints fabricated by direct current welding. The achieved effect manifests itself over the entire testing range from 20 to-60°C.

  5. Study of The Maximum Uptake Capacity on Various Sizes of Electric Arc Furnace Slag in Phosphorus Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Afnizan, W. M. W.; Hamdan, R.; Othman, N.

    2016-07-01

    The high content of uncontrolled phosphorus concentration in wastewater has emerged as a major problem recently. The excessive amount of phosphorus that is originated from domestic waste, unproper treated waste from septic tanks, as well as agricultural activities have led to the eutrophication problem. Therefore, a laboratory experiment was initiated to evaluate the potential of the Electric Arc Furnace Slag (EAFS), a by-product waste from steel making industry in removing phosphorus concentrations in aqueous solutions. In this work several particle sizes ranging from (9.5-12.4 mm, 12.5-15.9 mm, 16.0-19.9 mm, 20.0-24.9 mm, 25-37.4 mm) with a known weight (20±0.28 g, 40±0.27 g, 60±0.30 g, 80±0.29 g and 100±0.38 g) were used to study the effect of different particle sizes towards phosphorus removal. Each particle size of EAFS was shaken in synthetic phosphorus solutions (10 mg/l, 20 mg/l, 30 mg/l, 40 mg/l and 50 mg/l) at a contact time of 2 hours. Final concentrations of phosphorus were sampled and the measurement was made using WESTCO Discrete Analyzer equipment. Results showed that the highest of the maximum uptake capacity of each EAFS particle size distribution achieved at 0.287, 0.313, 0.266, 0.241 and 0.25 mg/g as particle size range was varied from 9.5-12.4 mm to 25-37.4 mm. In conclusion, the maximum uptake capacity of each EAFS mostly was determined to occur at adsorbent weight of 20 to 40 g in most conditions.

  6. 10. INTERIOR OF THE VERTICAL FURNACE BUILDING OF MACHINE SHOP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. INTERIOR OF THE VERTICAL FURNACE BUILDING OF MACHINE SHOP No. 2. STRUCTURE IN THE FOREGROUND IS THE UPENDER. THE QUENCH TOWER AND FURNACES ARE IN THE BACKGROUND. - U.S. Steel Homestead Works, Machine Shop No. 2, Along Monongahela River, Homestead, Allegheny County, PA

  7. A Goal Programming Optimization Model for The Allocation of Liquid Steel Production

    NASA Astrophysics Data System (ADS)

    Hapsari, S. N.; Rosyidi, C. N.

    2018-03-01

    This research was conducted in one of the largest steel companies in Indonesia which has several production units and produces a wide range of steel products. One of the important products in the company is billet steel. The company has four Electric Arc Furnace (EAF) which produces liquid steel which must be procesed further to be billet steel. The billet steel plant needs to make their production process more efficient to increase the productvity. The management has four goals to be achieved and hence the optimal allocation of the liquid steel production is needed to achieve those goals. In this paper, a goal programming optimization model is developed to determine optimal allocation of liquid steel production in each EAF, to satisfy demand in 3 periods and the company goals, namely maximizing the volume of production, minimizing the cost of raw materials, minimizing maintenance costs, maximizing sales revenues, and maximizing production capacity. From the results of optimization, only maximizing production capacity goal can not achieve the target. However, the model developed in this papare can optimally allocate liquid steel so the allocation of production does not exceed the maximum capacity of the machine work hours and maximum production capacity.

  8. Elements for the modeling of the thermal process in heating furnaces for steel forming

    NASA Astrophysics Data System (ADS)

    Constantinescu, D.; Carlan, A. B.

    2017-02-01

    In the present paper, by “modelling of thermal process” will be understood the thermal techniques modelling, applied to the heating of steel billets in a large scale, in view of processing by forming. These technologies are correlated with the particularities of the thermal aggregates, having as main objective the reducing of energy consumptions and the optimizing of the aggregate design. When heating the steel billets in view of processing by forming, the duration and the quality of heating are influenced by the modality that the billets are receiving the thermal flow. The reception of the thermal flow depends on the heated surface exposed to the thermal radiation in compliance with their position on the hearth of the heating aggregate. The present paper intends to establish some parameters in view of optimizing the heating process. A basic point of the work is also the determination of some components of a mathematical model for the proposed heating technology. The authors have in view the complexity of the technical evolutions of the furnaces.

  9. Multiphysics Modeling and Simulations of Mil A46100 Armor-Grade Martensitic Steel Gas Metal Arc Welding Process

    DTIC Science & Technology

    2013-05-23

    simulation of the conventional Gas Metal Arc Welding (GMAW) process, and the application of the developed methods and tools for prediction of the...technology in many industries such as chemical, oil , aerospace, and shipbuilding construction. In fact, within the metal fabrication industry as a...Mechanical Properties of Low Alloy Steel Products. Hardenability Concepts with Applications to Steel, The Metallurgical Society of AIME, Chicago, 1978, p

  10. Comprehensive Numerical Modeling of the Blast Furnace Ironmaking Process

    NASA Astrophysics Data System (ADS)

    Zhou, Chenn; Tang, Guangwu; Wang, Jichao; Fu, Dong; Okosun, Tyamo; Silaen, Armin; Wu, Bin

    2016-05-01

    Blast furnaces are counter-current chemical reactors, widely utilized in the ironmaking industry. Hot reduction gases injected from lower regions of the furnace ascend, reacting with the descending burden. Through this reaction process, iron ore is reduced into liquid iron that is tapped from the furnace hearth. Due to the extremely harsh environment inside the blast furnace, it is difficult to measure or observe internal phenomena during operation. Through the collaboration between steel companies and the Center for Innovation through Visualization and Simulation, multiple computational fluid dynamics (CFD) models have been developed to simulate the complex multiphase reacting flow in the three regions of the furnace, the shaft, the raceway, and the hearth. The models have been used effectively to troubleshoot and optimize blast furnace operations. In addition, the CFD models have been integrated with virtual reality. An interactive virtual blast furnace has been developed for training purpose. This paper summarizes the developments and applications of blast furnace CFD models and the virtual blast furnace.

  11. Blast furnace supervision and control system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Remorino, M.; Lingiardi, O.; Zecchi, M.

    1997-12-31

    On December 1992, a group of companies headed by Techint, took over Somisa, the state-owned integrated steel plant located at San Nicolas, Province of Buenos Aires, Argentina, culminating an ambitious government privatization scheme. The blast furnace 2 went into a full reconstruction and relining in January 1995. After a 140 MU$ investment the new blast furnace 2 was started in September 1995. After more than one year of operation of the blast furnace the system has proven itself useful and reliable. The main reasons for the success of the system are: same use interface for all blast furnace areas --more » operation, process, maintenance and management, (full horizontal and vertical integration); and full accessibility to all information and process tools though some restrictions apply to field commands (people empowerment). The paper describes the central system.« less

  12. Identifying the origins of local atmospheric deposition in the steel industry basin of Luxembourg using the chemical and isotopic composition of the lichen Xanthoria parietina.

    PubMed

    Hissler, Christophe; Stille, Peter; Krein, Andreas; Geagea, Majdi Lahd; Perrone, Thierry; Probst, Jean-Luc; Hoffmann, Lucien

    2008-11-01

    Trace metal atmospheric contamination was assessed in one of the oldest European industrial sites of steel production situated in the southern part of the Grand-Duchy of Luxembourg. Using elemental ratios as well as Pb, Sr, and Nd isotopic compositions as tracers, we found preliminary results concerning the trace metal enrichment and the chemical/isotopic signatures of the most important emission sources using the lichen Xanthoria parietina sampled at 15 sites along a SW-NE transect. The concentrations of these elements decreased with increasing distance from the historical and actual steel-work areas. The combination of the different tracers (major elements, Rare Earth Element ratios, Pb, Sr and Nd isotopes) enabled us to distinguish between three principal sources: the historical steel production (old tailings corresponding to blast-furnace residues), the present steel production (industrial sites with arc electric furnace units) and the regional background (baseline) components. Other anthropogenic sources including a waste incinerator and major roads had only weak impacts on lichen chemistry and isotopic ratios. The correlation between the Sr and Nd isotope ratios indicated that the Sr-Nd isotope systems represented useful tools to trace atmospheric emissions of factories using scrap metal for steel production.

  13. Fatigue Crack Growth Behavior of Gas Metal Arc Welded AISI 409 Grade Ferritic Stainless Steel Joints

    NASA Astrophysics Data System (ADS)

    Lakshminarayanan, A. K.; Shanmugam, K.; Balasubramanian, V.

    2009-10-01

    The effect of filler metals such as austenitic stainless steel, ferritic stainless steel, and duplex stainless steel on fatigue crack growth behavior of the gas metal arc welded ferritic stainless steel joints was investigated. Rolled plates of 4 mm thickness were used as the base material for preparing single ‘V’ butt welded joints. Center cracked tensile specimens were prepared to evaluate fatigue crack growth behavior. Servo hydraulic controlled fatigue testing machine with a capacity of 100 kN was used to evaluate the fatigue crack growth behavior of the welded joints. From this investigation, it was found that the joints fabricated by duplex stainless steel filler metal showed superior fatigue crack growth resistance compared to the joints fabricated by austenitic and ferritic stainless steel filler metals. Higher yield strength and relatively higher toughness may be the reasons for superior fatigue performance of the joints fabricated by duplex stainless steel filler metal.

  14. 12. INTERIOR VIEW OF SINGLE BAY SLOTTED TYPE FURNACE (LEFT) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. INTERIOR VIEW OF SINGLE BAY SLOTTED TYPE FURNACE (LEFT) AND CHAMBERSBURG DROP HAMMER OPERATED BY JEFF HOHMAN (RIGHT); THE FURNACE IS USED TO PRE-HEAT THE STEEL PRIOR TO FORGING, TOOL IS POST HOLE DIGGER WITH TAMPING BAR - Warwood Tool Company, Foot of Nineteenth Street, Wheeling, Ohio County, WV

  15. VIEW FROM THE SOUTH OF THE #2 BLAST FURNACE AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM THE SOUTH OF THE #2 BLAST FURNACE AND CASTING SEED ON THE LEFT, THE #1 BLAST FURNACE AND CASTING SHED ON THE RIGHT, AND THE STOVES, BOILERS, AND AUXILIARY EQUIPMENT IN THE CENTER. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  16. Cupola Furnace Computer Process Model

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seymour Katz

    2004-12-31

    The cupola furnace generates more than 50% of the liquid iron used to produce the 9+ million tons of castings annually. The cupola converts iron and steel into cast iron. The main advantages of the cupola furnace are lower energy costs than those of competing furnaces (electric) and the ability to melt less expensive metallic scrap than the competing furnaces. However the chemical and physical processes that take place in the cupola furnace are highly complex making it difficult to operate the furnace in optimal fashion. The results are low energy efficiency and poor recovery of important and expensive alloymore » elements due to oxidation. Between 1990 and 2004 under the auspices of the Department of Energy, the American Foundry Society and General Motors Corp. a computer simulation of the cupola furnace was developed that accurately describes the complex behavior of the furnace. When provided with the furnace input conditions the model provides accurate values of the output conditions in a matter of seconds. It also provides key diagnostics. Using clues from the diagnostics a trained specialist can infer changes in the operation that will move the system toward higher efficiency. Repeating the process in an iterative fashion leads to near optimum operating conditions with just a few iterations. More advanced uses of the program have been examined. The program is currently being combined with an ''Expert System'' to permit optimization in real time. The program has been combined with ''neural network'' programs to affect very easy scanning of a wide range of furnace operation. Rudimentary efforts were successfully made to operate the furnace using a computer. References to these more advanced systems will be found in the ''Cupola Handbook''. Chapter 27, American Foundry Society, Des Plaines, IL (1999).« less

  17. Novel sintered ceramic materials incorporated with EAF carbon steel slag

    NASA Astrophysics Data System (ADS)

    Karayannis, V.; Ntampegliotis, K.; Lamprakopoulos, S.; Papapolymerou, G.; Spiliotis, X.

    2017-01-01

    In the present research, novel sintered clay-based ceramic materials containing electric arc furnace carbon steel slag (EAFC) as a useful admixture were developed and characterized. The environmentally safe management of steel industry waste by-products and their valorization as secondary resources into value-added materials towards circular economy have attracted much attention in the last years. EAF Carbon steel slag in particular, is generated during the manufacture of carbon steel. It is a solid residue mainly composed of rich-in- Fe, Ca and Si compounds. The experimental results show that the beneficial incorporation of lower percentages of EAFC up to 6%wt. into ceramics sintered at 950 °C is attained without significant variations in sintering behavior and physico-mechanical properties. Further heating up to 1100 °C strongly enhances the densification of the ceramic microstructures, thus reducing the porosity and strengthening their mechanical performance. On the other side, in terms of thermal insulation behavior as well as energy consumption savings and production cost alleviation, the optimum sintering temperature appears to be 950 °C.

  18. [Utilization of a transferred arc-plasma rotating furnace to melt and found oxide mixtures at around 2000 degrees C (presentation of the film VULCANO)].

    PubMed

    Cognet, G; Laffont, G; Jegou, C; Pierre, J; Journeau, C; Sudreau, F; Roubaud, A

    1999-03-01

    Unless security measures are taken, a hypothetical accident resulting from the loss of the cooling circuit in a pressurized water nuclear reactor could cause the heart of the reactor to melt forming a bath, called the corium, mainly composed of uranium, zirconium and iron oxides as well as the structural steel. This type of situation would be similar to the Three Mile Island accident in 1979. In order to limit the consequences of such an accident, the Atomic Energy Commission has implemented a large study program [1] to improve our understanding of corium behavior and determine solutions to stabilize it and avoid its propagation outside the unit. The VULCANO installation was designed in order to perform the trials using real materials which are indispensable to study all the phenomena involved. A film on the VULCANO trials was presented at the Henri Moissan commemorative session organized by the French National Academy of Pharmacy. The rotating furnace used to melt and found the mixture simulating the corium is a direct descendant of the pioneer work by Henri Moissan. An electrical arc is directed at the center of the load to melt which is maintained against the walls by centrifugal force. After six high-temperature trials performed with compositions without uranium oxide, the first trial with real corium showed that the magma spread rather well, a result which is quite favorable for cooling.

  19. Thermodynamic analysis of the selective chlorination of electric arc furnace dust.

    PubMed

    Pickles, C A

    2009-07-30

    The remelting of automobile scrap in an electric arc furnace (EAF) results in the production of a dust, which contains high concentrations of the oxides of zinc, iron, calcium and other metals. Typically, the lead and zinc are of commercial value, while the other metals are not worth recovering. At the present time, EAF dusts are treated in high temperature Waelz rotary kiln-type processes, where the lead and zinc oxides are selectively reduced and simultaneously reoxidized and a crude zinc oxide is produced. Another alternative processing route is selective chlorination, in which the non-ferrous metals are preferentially chlorinated to their gaseous chlorides and in this manner separated from the iron. In the present research, a detailed thermodynamic analysis of this chlorination process has been performed and the following factors were investigated; temperature, amount of chlorine, lime content, silica content, presence of an inert gas and the oxygen potential. High lead and zinc recoveries as gaseous chlorides could be achieved but some of the iron oxide was also chlorinated. Additionally, the calcium oxide in the dust consumes chlorine, but this can be minimized by adding silica, which results in the formation of stable calcium silicates. The optimum conditions were determined for a typical dust composition. The selectivities achieved with chlorination were lower than those for reduction, as reported in the literature, but there are other advantages such as the potential recovery of copper.

  20. Structure and properties of Hardox 450 steel with arc welded coatings

    NASA Astrophysics Data System (ADS)

    Ivanov, Yu. F.; Konovalov, S. V.; Kormyshev, V. E.; Gromov, V. E.; Teresov, A. D.; Semina, O. A.

    2017-12-01

    The paper reports on a study of the surface structure, phase composition, and microhardness of Hardox 450 steel with coatings deposited by arc welding of powder wires differing in chemical composition. The study shows that to a depth of 6-8 mm, the microhardness of the thus formed coatings is more than two times the microhardness of the base metal and that their higher mechanical properties are provided by martensite structure containing Nb2C and NbC carbides and Fe2B borides as eutectic lamellae with a transverse size of 30-70 nm; their volume reveals a net-like dislocation substructure with a scalar dislocation density of 1011 cm-2. The highest surface hardness is found for the steel coated with boron-containing wire material. Some ideas are suggested on possible mechanisms and temperature for the formation of Nb and B carbides during the process.

  1. An update on blast furnace granular coal injection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hill, D.G.; Strayer, T.J.; Bouman, R.W.

    1997-12-31

    A blast furnace coal injection system has been constructed and is being used on the furnace at the Burns Harbor Division of Bethlehem Steel. The injection system was designed to deliver both granular (coarse) and pulverized (fine) coal. Construction was completed on schedule in early 1995. Coal injection rates on the two Burns Harbor furnaces were increased throughout 1995 and was over 200 lbs/ton on C furnace in September. The injection rate on C furnace reached 270 lbs/ton by mid-1996. A comparison of high volatile and low volatile coals as injectants shows that low volatile coal replaces more coke andmore » results in a better blast furnace operation. The replacement ratio with low volatile coal is 0.96 lbs coke per pound of coal. A major conclusion of the work to date is that granular coal injection performs very well in large blast furnaces. Future testing will include a processed sub-bituminous coal, a high ash coal and a direct comparison of granular versus pulverized coal injection.« less

  2. Microstructure of arc brazed and diffusion bonded joints of stainless steel and SiC reinforced aluminum matrix composite

    NASA Astrophysics Data System (ADS)

    Elßner, M.; Weis, S.; Grund, T.; Wagner, G.; Habisch, S.; Mayr, P.

    2016-03-01

    Joint interfaces of aluminum and stainless steel often exhibit intermetallics of Al-Fe, which limit the joint strength. In order to reduce these brittle phases in joints of aluminum matrix composites (AMC) and stainless steel, diffusion bonding and arc brazing are used. Due to the absence of a liquid phase, diffusion welding can reduce the formation of these critical in- termetallics. For this joining technique, the influence of surface treatments and adjusted time- temperature-surface-pressure-regimes is investigated. On the other hand, arc brazing offers the advantage to combine a localized heat input with the application of a low melting filler and was conducted using the system Al-Ag-Cu. Results of the joining tests using both approaches are described and discussed with regard to the microstructure of the joints and the interfaces.

  3. 9. GENERAL INTERIOR VIEW OF THE VERTICAL FURNACE BUILDING (PART ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. GENERAL INTERIOR VIEW OF THE VERTICAL FURNACE BUILDING (PART OF MACHINE SHOP No. 2). TWO FURNACES, WITH THEIR SUPPORT FRAMEWORK, ARE VISIBLE TO THE RIGHT. THE TALL STRUCTURE IN THE CENTER TOWARD THE BACKGROUND IS THE VERTICAL QUENCH TOWER. - U.S. Steel Homestead Works, Machine Shop No. 2, Along Monongahela River, Homestead, Allegheny County, PA

  4. Application of alkaline solid residue of electric arc furnace dust for neutralization/purification of electroplating wastewaters.

    PubMed

    Elez, Loris; Orescanin, Visnja; Sofilic, Tahir; Mikulic, Nenad; Ruk, Damir

    2008-10-01

    The purpose of this work was development of an appropriate procedure for the neutralization/purification of electroplating wastewater (EWW) with alkaline solid residue (ASR) by-product of the alkaline extraction of zinc and lead from electric arc furnace dust (EAFD). Removal efficiency of ASR at optimum purification conditions (pH 8 and mixing time; 20 minutes) for the elements Pb, Cr (VI), Cr (III), Fe, Ni, Cu and Zn were 94.92%, 97.58%, 99.59%, 99.48%, 97.25% and 99.97%, respectively. The concentrations of all elements in the purified wastewater were significantly lower in relation to the upper permissible limit for wastewaters suitable for discharge into the environment. The remaining waste mud was regenerated in the strong alkaline medium and successfully applied once again for the neutralization/purification of EWW. Removal efficiencies of heavy metals accomplished with regenerated waste mud were comparable to these achieved by original ASR. Elemental concentrations in the leachates of the waste mud were in accordance with regulated values.

  5. Effect of Cut Quality on Hybrid Laser Arc Welding of Thick Section Steels

    NASA Astrophysics Data System (ADS)

    Farrokhi, F.; Nielsen, S. E.; Schmidt, R. H.; Pedersen, S. S.; Kristiansen, M.

    From an industrial point of view, in a laser cutting-welding production chain, it is of great importance to know the influence of the attainable laser cut quality on the subsequent hybrid laser arc welding process. Many studies have been carried out in the literature to obtain lower surface roughness values on the laser cut edge. However, in practice, the cost and reliability of the cutting process is crucial and it does not always comply with obtaining the highest surface quality. In this study, a number of experiments on 25 mm steel plates were carried out to evaluate the influence of cut surface quality on the final quality of the subsequent hybrid laser welded joints. The different cut surfaces were obtained by different industrial cutting methods including laser cutting, abrasive water cutting, plasma cutting, and milling. It was found that the mentioned cutting methods could be used as preparation processes for the subsequent hybrid laser arc welding. However, cut quality could determine the choice of process parameters of the following hybrid laser arc welding.

  6. Studies on the Parametric Effects of Plasma Arc Welding of 2205 Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Selva Bharathi, R.; Siva Shanmugam, N.; Murali Kannan, R.; Arungalai Vendan, S.

    2018-03-01

    This research study attempts to create an optimized parametric window by employing Taguchi algorithm for Plasma Arc Welding (PAW) of 2 mm thick 2205 duplex stainless steel. The parameters considered for experimentation and optimization are the welding current, welding speed and pilot arc length respectively. The experimentation involves the parameters variation and subsequently recording the depth of penetration and bead width. Welding current of 60-70 A, welding speed of 250-300 mm/min and pilot arc length of 1-2 mm are the range between which the parameters are varied. Design of experiments is used for the experimental trials. Back propagation neural network, Genetic algorithm and Taguchi techniques are used for predicting the bead width, depth of penetration and validated with experimentally achieved results which were in good agreement. Additionally, micro-structural characterizations are carried out to examine the weld quality. The extrapolation of these optimized parametric values yield enhanced weld strength with cost and time reduction.

  7. Increase in the efficiency of electric melting of pellets in an arc furnace with allowance for the energy effect of afterburning of carbon oxide in slag using fuel-oxygen burners

    NASA Astrophysics Data System (ADS)

    Stepanov, V. A.; Krakht, L. N.; Merker, E. E.; Sazonov, A. V.; Chermenev, E. A.

    2015-12-01

    The problems of increasing the efficiency of electric steelmaking using fuel-oxygen burners to supply oxygen for the afterburning of effluent gases in an arc furnace are considered. The application of a new energy-saving regime based on a proposed technology of electric melting is shown to intensify the processes of slag formation, heating, and metal decarburization.

  8. Computational Fluid Dynamics Modeling of Supersonic Coherent Jets for Electric Arc Furnace Steelmaking Process

    NASA Astrophysics Data System (ADS)

    Alam, Morshed; Naser, Jamal; Brooks, Geoffrey; Fontana, Andrea

    2010-12-01

    Supersonic coherent gas jets are now used widely in electric arc furnace steelmaking and many other industrial applications to increase the gas-liquid mixing, reaction rates, and energy efficiency of the process. However, there has been limited research on the basic physics of supersonic coherent jets. In the present study, computational fluid dynamics (CFD) simulation of the supersonic jet with and without a shrouding flame at room ambient temperature was carried out and validated against experimental data. The numerical results show that the potential core length of the supersonic oxygen and nitrogen jet with shrouding flame is more than four times and three times longer, respectively, than that without flame shrouding, which is in good agreement with the experimental data. The spreading rate of the supersonic jet decreased dramatically with the use of the shrouding flame compared with a conventional supersonic jet. The present CFD model was used to investigate the characteristics of the supersonic coherent oxygen jet at steelmaking conditions of around 1700 K (1427 °C). The potential core length of the supersonic coherent oxygen jet at steelmaking conditions was 1.4 times longer than that at room ambient temperature.

  9. A Comparison of Iron and Steel Production Energy Use and Energy Intensity in China and the U.S.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hasanbeigi, Ali; Price, Lynn; Aden, Nathaniel

    Production of iron and steel is an energy-intensive manufacturing process. In 2006, the iron and steel industry accounted for 13.6% and 1.4% of primary energy consumption in China and the U.S., respectively (U.S. DOE/EIA, 2010a; Zhang et al., 2010). The energy efficiency of steel production has a direct impact on overall energy consumption and related carbon dioxide (CO2) emissions. The goal of this study is to develop a methodology for making an accurate comparison of the energy intensity (energy use per unit of steel produced) of steel production. The methodology is applied to the steel industry in China and themore » U.S. The methodology addresses issues related to boundary definitions, conversion factors, and indicators in order to develop a common framework for comparing steel industry energy use. This study uses a bottom-up, physical-based method to compare the energy intensity of China and U.S. crude steel production in 2006. This year was chosen in order to maximize the availability of comparable steel-sector data. However, data published in China and the U.S. are not always consistent in terms of analytical scope, conversion factors, and information on adoption of energy-saving technologies. This study is primarily based on published annual data from the China Iron & Steel Association and National Bureau of Statistics in China and the Energy Information Agency in the U.S. This report found that the energy intensity of steel production is lower in the United States than China primarily due to structural differences in the steel industry in these two countries. In order to understand the differences in energy intensity of steel production in both countries, this report identified key determinants of sector energy use in both countries. Five determinants analyzed in this report include: share of electric arc furnaces in total steel production, sector penetration of energy-efficiency technologies, scale of production equipment, fuel shares in the iron and

  10. Utilisation of steel furnace slag coarse aggregate in a low calcium fly ash geopolymer concrete

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khan, M. S.H.,; Castel, Arnaud; Akbarnezhad, A.

    This paper evaluates the performance of steel furnace slag (SFS) coarse aggregate in blended slag and low calcium fly ash geopolymer concrete (GPC). The geopolymer binder is composed of 90% of low calcium fly ash and 10% of ground granulated blast furnace slag (GGBFS). Mechanical and physical properties, shrinkage, and detailed microstructure analysis were carried out. The results showed that geopolymer concrete with SFS aggregate offered higher compressive strength, surface resistivity and pulse velocity than that of GPC with traditional aggregate. The shrinkage results showed no expansion or swelling due to delayed calcium oxide (CaO) hydration after 320 days. Nomore » traditional porous interfacial transition zone (ITZ) was detected using scanning electron microscopy, indicating a better bond between SFS aggregate and geopolymer matrix. Energy dispersive spectroscopy results further revealed calcium (Ca) diffusion at the vicinity of ITZ. Raman spectroscopy results showed no new crystalline phase formed due to Ca diffusion. X-ray fluorescence result showed Mg diffusion from SFS aggregate towards geopolymer matrix. The incorporation of Ca and Mg into the geopolymer structure and better bond between SFS aggregate and geopolymer matrix are the most likely reasons for the higher compressive strength observed in GPC with SFS aggregate.« less

  11. 40 CFR 63.7734 - How do I demonstrate initial compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... used to demonstrate compliance. (1) For each electric arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing iron and steel foundry, (i) The average PM... not exceed 0.0002 gr/dscf. (4) For each electric induction metal melting furnace or scrap preheater at...

  12. 40 CFR 63.7734 - How do I demonstrate initial compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... used to demonstrate compliance. (1) For each electric arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing iron and steel foundry, (i) The average PM... not exceed 0.0002 gr/dscf. (4) For each electric induction metal melting furnace or scrap preheater at...

  13. 40 CFR 63.7734 - How do I demonstrate initial compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... used to demonstrate compliance. (1) For each electric arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing iron and steel foundry, (i) The average PM... not exceed 0.0002 gr/dscf. (4) For each electric induction metal melting furnace or scrap preheater at...

  14. 40 CFR 63.7734 - How do I demonstrate initial compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... used to demonstrate compliance. (1) For each electric arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing iron and steel foundry, (i) The average PM... not exceed 0.0002 gr/dscf. (4) For each electric induction metal melting furnace or scrap preheater at...

  15. 40 CFR 63.7734 - How do I demonstrate initial compliance with the emissions limitations that apply to me?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... used to demonstrate compliance. (1) For each electric arc metal melting furnace, electric induction metal melting furnace, or scrap preheater at an existing iron and steel foundry, (i) The average PM... not exceed 0.0002 gr/dscf. (4) For each electric induction metal melting furnace or scrap preheater at...

  16. The Effect of Constant and Pulsed Current Gas Tungsten Arc Welding on Joint Properties of 2205 Duplex Stainless Steel to 316L Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Neissi, R.; Shamanian, M.; Hajihashemi, M.

    2016-05-01

    In this study, dissimilar 316L austenitic stainless steel/2205 duplex stainless steel (DSS) joints were fabricated by constant and pulsed current gas tungsten arc welding process using ER2209 DSS as a filler metal. Microstructures and joint properties were characterized using optical and electron scanning microscopy, tensile, Charpy V-notch impact and micro-hardness tests, and cyclic polarization measurements. Microstructural observations confirmed the presence of chromium nitride and delta ferrite in the heat-affected zone of DSS and 316L, respectively. In addition, there was some deviation in the austenite/ferrite ratio of the surface welding pass in comparison to the root welding pass. Besides having lower pitting potential, welded joints produced by constant current gas tungsten arc welding process, consisted of some brittle sigma phase precipitates, which resulted in some impact energy reduction. The tensile tests showed high tensile strength for the weld joints in which all the specimens were broken in 316L base metal.

  17. Application of AI techniques to blast furnace operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Iida, Osamu; Ushijima, Yuichi; Sawada, Toshiro

    1995-10-01

    It was during the first stages of application of artificial intelligence (AI) to industrial fields, that the ironmaking division of Mizushima works at Kawasaki Steel recognized its potential. Since that time, the division has sought applications for these techniques to solve various problems. AI techniques applied to control the No. 3 blast furnace operations at the Mizushima works include: Blast furnace control by a diagnostic type of expert system that gives guidance to the actions required for blast furnace operation as well as control of furnace heat by automatically setting blast temperature; Hot stove combustion control by a combination ofmore » fuzzy inference and a physical model to insure good thermal efficiency of the stove; and blast furnace burden control using neural networks makes it possible to connect the pattern of gas flow distribution with the condition of the furnace. Experience of AI to control the blast furnace and other ironmaking operations has proved its capability for achieving automation and increased operating efficiency. The benefits are very high. For these reasons, the applications of AI techniques will be extended in the future and new techniques studied to further improve the power of AI.« less

  18. Dilution in single pass arc welds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DuPont, J.N.; Marder, A.R.

    1996-06-01

    A study was conducted on dilution of single pass arc welds of type 308 stainless steel filler metal deposited onto A36 carbon steel by the plasma arc welding (PAW), gas tungsten arc welding (GTAW), gas metal arc welding (GMAW), and submerged arc welding (SAW) processes. Knowledge of the arc and melting efficiency was used in a simple energy balance to develop an expression for dilution as a function of welding variables and thermophysical properties of the filler metal and substrate. Comparison of calculated and experimentally determined dilution values shows the approach provides reasonable predictions of dilution when the melting efficiencymore » can be accurately predicted. The conditions under which such accuracy is obtained are discussed. A diagram is developed from the dilution equation which readily reveals the effect of processing parameters on dilution to aid in parameter optimization.« less

  19. Dissimilar Joining of Stainless Steel and 5083 Aluminum Alloy Sheets by Gas Tungsten Arc Welding-Brazing Process

    NASA Astrophysics Data System (ADS)

    Cheepu, Muralimohan; Srinivas, B.; Abhishek, Nalluri; Ramachandraiah, T.; Karna, Sivaji; Venkateswarlu, D.; Alapati, Suresh; Che, Woo Seong

    2018-03-01

    The dissimilar joining using gas tungsten arc welding - brazing of 304 stainless steel to 5083 Al alloy had been conducted with the addition of Al-Cu eutectic filler metal. The interface microstructure formation between filler metal and substrates, and spreading of the filler metal were studied. The interface microstructure between filler metal and aluminum alloy characterized that the formation of pores and elongated grains with the initiation of micro cracks. The spreading of the liquid braze filler on stainless steel side packed the edges and appeared as convex shape, whereas a concave shape has been formed on aluminum side. The major compounds formed at the fusion zone interface were determined by using X-ray diffraction techniques and energy-dispersive X-ray spectroscopy analysis. The micro hardness at the weld interfaces found to be higher than the substrates owing to the presence of Fe2Al5 and CuAl2 intermetallic compounds. The maximum tensile strength of the weld joints was about 95 MPa, and the tensile fracture occurred at heat affected zone on weak material of the aluminum side and/or at stainless steel/weld seam interface along intermetallic layer. The interface formation and its effect on mechanical properties of the welds during gas tungsten arc welding-brazing has been discussed.

  20. 49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a water... a maximum wall stress of 24,000 p.s.i. in the formula described in paragraph (f)(4) of this section... any case the minimum wall thickness must be such that the wall stress calculated by the formula listed...

  1. 49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a water... a maximum wall stress of 24,000 p.s.i. in the formula described in paragraph (f)(4) of this section... any case the minimum wall thickness must be such that the wall stress calculated by the formula listed...

  2. [Health surveillance in a steel making industry with electric arc furnace: 15 years of experience].

    PubMed

    Corti, P

    2012-01-01

    This paper analyzes the results of health surveillance carried out in an electric steel mill for 15 years. We have analyzed the trend of audiometry, spirometry and main indicators of exposure to chemical risk: serum lead, urinary OH-pyrene, erythrocyte ZPP, and the results of risk assessment of stress work related. The analyses of the trend of audiometry, spirometry and biological monitoring shows an important improving in the working environment due to the progressive automation of production steps in the course of several years, consistent and correct use of DPI, information and training.

  3. Post-weld Tempered Microstructure and Mechanical Properties of Hybrid Laser-Arc Welded Cast Martensitic Stainless Steel CA6NM

    NASA Astrophysics Data System (ADS)

    Mirakhorli, Fatemeh; Cao, Xinjin; Pham, Xuan-Tan; Wanjara, Priti; Fihey, Jean-Luc

    2016-12-01

    Manufacturing of hydroelectric turbine components involves the assembly of thick-walled stainless steels using conventional multi-pass arc welding processes. By contrast, hybrid laser-arc welding may be an attractive process for assembly of such materials to realize deeper penetration depths, higher production rates, narrower fusion, and heat-affected zones, and lower distortion. In the present work, single-pass hybrid laser-arc welding of 10-mm thick CA6NM, a low carbon martensitic stainless steel, was carried out in the butt joint configuration using a continuous wave fiber laser at its maximum power of 5.2 kW over welding speeds ranging from 0.75 to 1.2 m/minute. The microstructures across the weldment were characterized after post-weld tempering at 873 K (600 °C) for 1 hour. From microscopic examinations, the fusion zone was observed to mainly consist of tempered lath martensite and some residual delta-ferrite. The mechanical properties were evaluated in the post-weld tempered condition and correlated to the microstructures and defects. The ultimate tensile strength and Charpy impact energy values of the fully penetrated welds in the tempered condition were acceptable according to ASTM, ASME, and industrial specifications, which bodes well for the introduction of hybrid laser-arc welding technology for the manufacturing of next generation hydroelectric turbine components.

  4. Modeling macro-and microstructures of gas-metal-arc welded HSLA-100 steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Z.; Debroy, T.

    1999-06-01

    Fluid flow and heat transfer during gas-metal-arc welding (GMAW) of HSLA-100 steel were studied using a transient, three-dimensional, turbulent heat transfer and fluid flow model. The temperature and velocity fields, cooling rates, and shape and size of the fusion and heat-affected zones (HAZs) were calculated. A continuous-cooling-transformation (CCT) diagram was computed to aid in the understanding of the observed weld metal microstructure. The computed results demonstrate that the dissipation of heat and momentum in the weld pool is significantly aided by turbulence,m thus suggesting that previous modeling results based on laminar flow need to be re-examined. A comparison of themore » calculated fusion and HAZ geometries with their corresponding measured values showed good agreement. Furthermore, finger penetration, a unique geometric characteristic of gas-metal-arc weld pools, could be satisfactorily predicted from the model. The ability to predict these geometric variables and the agreement between the calculated and the measured cooling rates indicate the appropriateness of using a turbulence model for accurate calculations. The microstructure of the weld metal consisted mainly of acicular ferrite with small amounts of bainite. At high heat inputs, small amounts of allotriomorphic and Widmanstaetten ferrite were also observed. The observed microstructures are consistent with those expected from the computed CCT diagram and the cooling rates. The results presented here demonstrate significant promise for understanding both macro-and microstructures of steel welds from the combination of the fundamental principles from both transport phenomena and phase transformation theory.« less

  5. Modeling macro-and microstructures of Gas-Metal-Arc Welded HSLA-100 steel

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Debroy, T.

    1999-06-01

    Fluid flow and heat transfer during gas-metal-arc welding (GMAW) of HSLA-100 steel were studied using a transient, three-dimensional, turbulent heat transfer and fluid flow model. The temperature and velocity fields, cooling rates, and shape and size of the fusion and heat-affected zones (HAZs) were calculated. A continuous-cooling-transformation (CCT) diagram was computed to aid in the understanding of the observed weld metal microstructure. The computed results demonstrate that the dissipation of heat and momentum in the weld pool is significantly aided by turbulence, thus suggesting that previous modeling results based on laminar flow need to be re-examined. A comparison of the calculated fusion and HAZ geometries with their corresponding measured values showed good agreement. Furthermore, “finger” penetration, a unique geometric characteristic of gas-metal-arc weld pools, could be satisfactorily predicted from the model. The ability to predict these geometric variables and the agreement between the calculated and the measured cooling rates indicate the appropriateness of using a turbulence model for accurate calculations. The microstructure of the weld metal consisted mainly of acicular ferrite with small amounts of bainite. At high heat inputs, small amounts of allotriomorphic and Widmanstätten ferrite were also observed. The observed microstructures are consistent with those expected from the computed CCT diagram and the cooling rates. The results presented here demonstrate significant promise for understanding both macro-and microstructures of steel welds from the combination of the fundamental principles from both transport phenomena and phase transformation theory.

  6. Comparison of the behavior of stainless and mild steel manual metal arc welding fumes in rat lung.

    PubMed

    Kalliomäki, P L; Junttila, M L; Kalliomäki, K K; Lakomaa, E L; Kivelä, R

    1983-04-01

    The lung retention and clearance of manual metal arc (MMA) stainless steel and mild steel welding fumes were determined in the rat. The exposure simulated the actual welding situation. The duration of exposure in the "nose-only" exposure chamber was 1 h/workday for one, two, three, or four weeks in the retention study and for four weeks in the clearance study. The concentration of exogenous iron was determined by the magnetic measuring method. Instrumental neutron activation analysis was applied to determine the concentration of total iron, chromium, and nickel in the lungs. The results indicated that the lung retention and clearance patterns for the two types of welding fumes were different. A linear relationship was observed between the amount of stainless steel MMA welding fume retained in the lungs and the duration of exposure, whereas the retention of mild steel MMA welding fume in the lung was saturated as a function of the cumulative exposure time rates. The maximum amount of lung-retained contaminants was 880 micrograms for stainless steel MMA welding fume and 220 micrograms for mild steel MMA fume.

  7. EAF Management Optimization

    NASA Astrophysics Data System (ADS)

    Costoiu, M.; Ioana, A.; Semenescu, A.; Marcu, D.

    2016-11-01

    The article presents the main advantages of electric arc furnace (EAF): it has a great contribution to reintroduce significant quantities of reusable metallic materials in the economic circuit, it constitutes itself as an important part in the Primary Materials and Energy Recovery (PMER), good productivity, good quality / price ratio, the possibility of developing a wide variety of classes and types of steels, including special steels and high alloy. In this paper it is presented some important developments of electric arc furnace: vacuum electric arc furnace, artificial intelligence expert systems for pollution control Steelworks. Another important aspect presented in the article is an original block diagram for optimization the EAF management system. This scheme is based on the original objective function (criterion function) represented by the price / quality ratio. The article presents an original block diagram for optimization the control system of the EAF. For designing this concept of EAF management system, many principles were used.

  8. Applications of thermal energy storage to process heat and waste heat recovery in the iron and steel industry

    NASA Technical Reports Server (NTRS)

    Katter, L. B.; Peterson, D. J.

    1978-01-01

    The system identified operates from the primary arc furnace evacuation system as a heat source. Energy from the fume stream is stored as sensible energy in a solid medium (packed bed). A steam-driven turbine is arranged to generate power for peak shaving. A parametric design approach is presented since the overall system design, at optimum payback is strongly dependent upon the nature of the electric pricing structure. The scope of the project was limited to consideration of available technology so that industry-wide application could be achieved by 1985. A search of the literature, coupled with interviews with representatives of major steel producers, served as the means whereby the techniques and technologies indicated for the specific site are extrapolated to the industry as a whole and to the 1985 time frame. The conclusion of the study is that by 1985, a national yearly savings of 1.9 million barrels of oil could be realized through recovery of waste heat from primary arc furnace fume gases on an industry-wide basis. Economic studies indicate that the proposed system has a plant payback time of approximately 5 years.

  9. Modeling and Simulation of the Off-gas in an Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Meier, Thomas; Gandt, Karima; Echterhof, Thomas; Pfeifer, Herbert

    2017-12-01

    The following paper describes an approach to process modeling and simulation of the gas phase in an electric arc furnace (EAF). The work presented represents the continuation of research by Logar, Dovžan, and Škrjanc on modeling the heat and mass transfer and the thermochemistry in an EAF. Due to the lack of off-gas measurements, Logar et al. modeled a simplified gas phase under consideration of five gas components and simplified chemical reactions. The off-gas is one of the main continuously measurable EAF process values and the off-gas flow represents a heat loss up to 30 pct of the entire EAF energy input. Therefore, gas phase modeling offers further development opportunities for future EAF optimization. This paper presents the enhancement of the previous EAF gas phase modeling by the consideration of additional gas components and a more detailed heat and mass transfer modeling. In order to avoid the increase of simulation time due to more complex modeling, the EAF model has been newly implemented to use an efficient numerical solver for ordinary differential equations. Compared to the original model, the chemical components H2, H2O, and CH4 are included in the gas phase and equilibrium reactions are implemented. The results show high levels of similarity between the measured operational data from an industrial scale EAF and the theoretical data from the simulation within a reasonable simulation time. In the future, the dynamic EAF model will be applicable for on- and offline optimizations, e.g., to analyze alternative input materials and mode of operations.

  10. 102. Giullotine type gate (inclosed position to regulate furnace exhaust ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    102. Giullotine type gate (inclosed position to regulate furnace exhaust gases to stoves during heating cycle. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  11. 8. VIEW OF BATCHING HOPPER ON SERVICE FLOOR OF FURNACE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW OF BATCHING HOPPER ON SERVICE FLOOR OF FURNACE AISLE IN BOP SHOP LOOKING SOUTH. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  12. Effect of Auxiliary Preheating of the Filler Wire on Quality of Gas Metal Arc Stainless Steel Claddings

    NASA Astrophysics Data System (ADS)

    Shahi, Amandeep S.; Pandey, Sunil

    2008-02-01

    Weld cladding is a process for producing surfaces with good corrosion resistant properties by means of depositing/laying of stainless steels on low-carbon steel components with an objective of achieving maximum economy and enhanced life. The aim of the work presented here was to investigate the effect of auxiliary preheating of the solid filler wire in mechanized gas metal arc welding (GMAW) process (by using a specially designed torch to preheat the filler wire independently, before its emergence from the torch) on the quality of the as-welded single layer stainless steel overlays. External preheating of the filler wire resulted in greater contribution of arc energy by resistive heating due to which significant drop in the main welding current values and hence low dilution levels were observed. Metallurgical aspects of the as welded overlays such as chemistry, ferrite content, and modes of solidification were studied to evaluate their suitability for service and it was found that claddings obtained through the preheating arrangement, besides higher ferrite content, possessed higher content of chromium, nickel, and molybdenum and lower content of carbon as compared to conventional GMAW claddings, thereby giving overlays with superior mechanical and corrosion resistance properties. The findings of this study not only establish the technical superiority of the new process, but also, owing to its productivity-enhanced features, justify its use for low-cost surfacing applications.

  13. Arc melting and homogenization of ZrC and ZrC + B alloys

    NASA Technical Reports Server (NTRS)

    Darolia, R.; Archbold, T. F.

    1973-01-01

    A description is given of the methods used to arc-melt and to homogenize near-stoichiometric ZrC and ZrC-boron alloys, giving attention to the oxygen contamination problem. The starting material for the carbide preparation was ZrC powder with an average particle size of 4.6 micron. Pellets weighing approximately 3 g each were prepared at room temperature from the powder by the use of an isostatic press operated at 50,000 psi. These pellets were individually melted in an arc furnace containing a static atmosphere of purified argon. A graphite resistance furnace was used for the homogenization process.

  14. Utilization of Electric Arc Furnace Dust as raw material for the production of ceramic and concrete building products.

    PubMed

    Sikalidis, Constantine; Mitrakas, Manassis

    2006-01-01

    The up to 20 wt% addition of the Electric Arc Furnace Dust (EAFD) hazardous waste on the properties of extruded clay-based ceramic building products fired at various temperatures (850 to 1050 degrees C), as well as of dolomite-concrete products was investigated. Chemical, mineralogical and particle size distribution analyses were performed in order to characterize the used EAFD. The results showed that the ceramic specimens prepared had water absorption, firing shrinkage, apparent density, mechanical strength, colour and leaching behaviour within accepted limits. Addition of 7.5 to 15 wt% EAFD presented improved properties, while 20 wt% seems to be the upper limit. Dolomite-concrete specimens were prepared by vibration and press-forming of mixtures containing cement, sand, dolomite, EAFD and water. Modulus of rupture values were significantly increased by the addition of EAFD. The leaching tests showed stabilization of all toxic metals within the sintered ceramic structure, while the leaching behaviour of lead in dolomite-concrete products needs further detailed study.

  15. Information modeling system for blast furnace control

    NASA Astrophysics Data System (ADS)

    Spirin, N. A.; Gileva, L. Y.; Lavrov, V. V.

    2016-09-01

    Modern Iron & Steel Works as a rule are equipped with powerful distributed control systems (DCS) and databases. Implementation of DSC system solves the problem of storage, control, protection, entry, editing and retrieving of information as well as generation of required reporting data. The most advanced and promising approach is to use decision support information technologies based on a complex of mathematical models. The model decision support system for control of blast furnace smelting is designed and operated. The basis of the model system is a complex of mathematical models created using the principle of natural mathematical modeling. This principle provides for construction of mathematical models of two levels. The first level model is a basic state model which makes it possible to assess the vector of system parameters using field data and blast furnace operation results. It is also used to calculate the adjustment (adaptation) coefficients of the predictive block of the system. The second-level model is a predictive model designed to assess the design parameters of the blast furnace process when there are changes in melting conditions relative to its current state. Tasks for which software is developed are described. Characteristics of the main subsystems of the blast furnace process as an object of modeling and control - thermal state of the furnace, blast, gas dynamic and slag conditions of blast furnace smelting - are presented.

  16. Engineering study for a melting, casting, rolling and fabrication facility for recycled contaminated stainless steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    This Preliminary Report is prepared to study the facilities required for recycling contaminated stainless steel scrap into plate which will be fabricated into boxes suitable for the storage of contaminated wastes and rubble. The study is based upon the underlying premise that the most cost effective way to produce stainless steel is to use the same processes employed by companies now in production of high quality stainless steel. Therefore, the method selected for this study for the production of stainless steel plate from scrap is conventional process using an Electric Arc Furnace for meltdown to hot metal, a Continuous Castermore » for production of cast slabs, and a Reversing Hot Mill for rolling the slabs into plate. The fabrication of boxes from the plate utilizes standard Shears, Punch Presses and welding equipment with Robotic Manipulators. This Study presumes that all process fumes, building dusts and vapors will be cycled through a baghouse and a nuclear grade HEPA filter facility prior to discharge. Also, all process waste water will be evaporated into the hot flue gas stream from the furnace utilizing a quench tank; so there will be no liquid discharges from the facility and all vapors will be processed through a HEPA filter. Even though HEPA filters are used today in controlling radioactive contamination from nuclear facilities there is a sparsity of data concerning radioactivity levels and composition of waste that may be collected from contaminated scrap steel processing. This report suggests some solutions to these problems but it is recommended that additional study must be given to these environmental problems.« less

  17. Optimization of hybrid laser arc welding of 42CrMo steel to suppress pore formation

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Chen, Genyu; Mao, Shuai; Zhou, Cong; Chen, Fei

    2017-06-01

    The hybrid laser arc welding (HLAW) of 42CrMo quenched and tempered steel was conducted. The effect of the processing parameters, such as the relative positions of the laser and the arc, the shielding gas flow rate, the defocusing distance, the laser power, the wire feed rate and the welding speed, on the pore formation was analyzed, the morphological characteristics of the pores were analyzed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results showed that the majority of the pores were invasive. The pores formed at the leading a laser (LA) welding process were fewer than those at the leading a arc (AL) welding process. Increasing the shielding gas flow rate could also facilitate the reduction of pores. The laser power and the welding speed were two key process parameters to reduce the pores. The flow of the molten pool, the weld cooling rate and the pore escaping rate as a result of different parameters could all affect pore formation. An ideal pore-free weld was obtained for the optimal welding process parameters.

  18. Preliminary Results from Electric Arc Furnace Off-Gas Enthalpy Modeling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nimbalkar, Sachin U; Thekdi, Arvind; Keiser, James R

    2015-01-01

    This article describes electric arc furnace (EAF) off-gas enthalpy models developed at Oak Ridge National Laboratory (ORNL) to calculate overall heat availability (sensible and chemical enthalpy) and recoverable heat values (steam or power generation potential) for existing EAF operations and to test ORNL s new EAF waste heat recovery (WHR) concepts. ORNL s new EAF WHR concepts are: Regenerative Drop-out Box System and Fluidized Bed System. The two EAF off-gas enthalpy models described in this paper are: 1.Overall Waste Heat Recovery Model that calculates total heat availability in off-gases of existing EAF operations 2.Regenerative Drop-out Box System Model in whichmore » hot EAF off-gases alternately pass through one of two refractory heat sinks that store heat and then transfer it to another gaseous medium These models calculate the sensible and chemical enthalpy of EAF off-gases based on the off-gas chemical composition, temperature, and mass flow rate during tap to tap time, and variations in those parameters in terms of actual values over time. The models provide heat transfer analysis for the aforementioned concepts to confirm the overall system and major component sizing (preliminary) to assess the practicality of the systems. Real-time EAF off-gas composition (e.g., CO, CO2, H2, and H2O), volume flow, and temperature data from one EAF operation was used to test the validity and accuracy of the modeling work. The EAF off-gas data was used to calculate the sensible and chemical enthalpy of the EAF off-gases to generate steam and power. The article provides detailed results from the modeling work that are important to the success of ORNL s EAF WHR project. The EAF WHR project aims to develop and test new concepts and materials that allow cost-effective recovery of sensible and chemical heat from high-temperature gases discharged from EAFs.« less

  19. Power Quality Improvement in Induction Furnace by Harmonic Reduction Using Dynamic Voltage Restorer

    NASA Astrophysics Data System (ADS)

    Saggu, Tejinder Singh; Singh, Lakhwinder

    2016-06-01

    Induction furnaces are used in wide quantity under different capacities for annual production of around 25 million tons of iron and steel in India. It plays a vital role in various manufacturing processes around the world for melting different types of metal scraps i. e. Copper, Cast Iron, Aluminium, Steel, Brass, Bronze, Silicon, Gold, Silver etc. which are further used in many other industrial applications. The induction furnace causes a huge disturbance to the utility and nearby consumers during its operation due to its non-linear characteristics. This is a serious phenomenon responsible for power quality degradation in the power system. This paper presents methodology to improve the power quality degradation caused by induction furnace using Dynamic Voltage Restorer (DVR) which is a type of custom power device. The real time data has been taken from an industry employing induction furnace for production of ingots from scrap material. The experimental readings are measured using power quality analyser equipment. The simulation of whole plant is done by analysing this same data and the simulation results are compared with actual onsite results. Then, solution methodology using DVR is presented which revealed that the implementation of DVR is an effective solution for voltage sag mitigation and harmonics improvement in induction furnace.

  20. A Heat and Mass Transfer Model of a Silicon Pilot Furnace

    NASA Astrophysics Data System (ADS)

    Sloman, Benjamin M.; Please, Colin P.; Van Gorder, Robert A.; Valderhaug, Aasgeir M.; Birkeland, Rolf G.; Wegge, Harald

    2017-10-01

    The most common technological route for metallurgical silicon production is to feed quartz and a carbon source ( e.g., coal, coke, or charcoal) into submerged-arc furnaces, which use electrodes as electrical conductors. We develop a mathematical model of a silicon furnace. A continuum approach is taken, and we derive from first principles the equations governing the time evolution of chemical concentrations, gas partial pressures, velocity, and temperature within a one-dimensional vertical section of a furnace. Numerical simulations are obtained for this model and are shown to compare favorably with experimental results obtained using silicon pilot furnaces. A rising interface is shown to exist at the base of the charge, with motion caused by the heating of the pilot furnace. We find that more reactive carbon reduces the silicon monoxide losses, while reducing the carbon content in the raw material mixture causes greater solid and liquid material to build-up in the charge region, indicative of crust formation (which can be detrimental to the silicon production process). We also comment on how the various findings could be relevant for industrial operations.

  1. 8. QUENCHING MECHANISM FOR THE CONTINUOUS ELECTRIC FURNACE HEAT TREATING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. QUENCHING MECHANISM FOR THE CONTINUOUS ELECTRIC FURNACE HEAT TREATING LINE AT THE HEAT TREATMENT PLANT OF THE DUQUESNE WORKS. - U.S. Steel Duquesne Works, Heat Treatment Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  2. Thermal Analysis on the Pyrolysis of Tetrabromobisphenol A and Electric Arc Furnace Dust Mixtures

    NASA Astrophysics Data System (ADS)

    Al-Harahsheh, Mohammad; Al-Otoom, Awni; Al-Jarrah, Muhannad; Altarawneh, Mohammednoor; Kingman, Sam

    2018-02-01

    The pyrolysis of Tetrabromobisphenol A (TBBPA) mixed with electric arc furnace dust (EAFD) was studied using thermogravimetric analysis (TGA) and theoretically analyzed using thermodynamic equilibrium calculations. Mixtures of both materials with varying TBBPA loads (1:1 and 1:3) were prepared and pyrolyzed in a nitrogen atmosphere under dynamic heating conditions at heating rates of 5 and 10 °C/min. The mixtures degraded through several steps, including decomposition of TBBPA yielding mainly HBr, bromination of metal oxides, followed by their evaporation in the sequence of CuBr3, ZnBr2, PbBr2, FeBr2, MnBr2, KBr, NaBr, CaBr2, and MgBr2, and finally reduction of the remaining metal oxides by the char formed from decomposition of TBBPA. Thermodynamic calculations suggest the possibility of selective bromination of zinc and lead followed by their evaporation, leaving iron in its oxide form, while the char formed may serve as a reduction agent for iron oxides into metallic iron. However, at higher TBBPA volumes, iron bromide forms, which can also be evaporated at a temperature higher than those of ZnBr2 and PbBr2. Results from this work provide practical insight into selective recovery of valuable metals from EAFD while at the same time recycling the hazardous bromine content in TBBPA.

  3. INTERIOR VIEW LOOKING EAST, SHOWING HEROULT NO. 2 FURNACE (ca. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW LOOKING EAST, SHOWING HEROULT NO. 2 FURNACE (ca. 1920) AND DETAIL OF CABLES AND BUS BARS (which convey power to electrodes) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  4. 38. DETAIL OF COOLING WATER BOOSTER PUMP FOR OXYGEN FURNACES, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. DETAIL OF COOLING WATER BOOSTER PUMP FOR OXYGEN FURNACES, LANCES, AND FUME HOODS IN THE GAS WASHER PUMP HOUSE LOOKING EAST. - U.S. Steel Duquesne Works, Basic Oxygen Steelmaking Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  5. The humoral immune response of mice exposed to manual metal arc stainless steel-welding fumes.

    PubMed

    Anderson, Stacey E; Meade, B Jean; Butterworth, Leon F; Munson, Albert E

    2007-01-01

    Arc welding is one of the most common forms of welding and includes the use of stainless steel electrodes that emit fumes containing chromium and nickel. Epidemological studies suggest a correlation between arc welding and adverse respiratory health effects. Studies evaluating the immunotoxic effects of welding fumes are limited due to the large number of variables associated with welding. This work investigates the immunotoxic effects of welding fumes by analyzing the in vivo and in vitro IgM response to a T-dependent antigen after welding fume exposure. Significant decreases in the total IgM activity/10(6) viable cells and total IgM activity/well were observed in splenocytes exposed to 5 mu g/ml of either total or soluble welding fumes. A significant reduction in the specific IgM activity in lung associated lymph node cells was also observed following four pharyngeal aspirations of 10 mg/kg total or soluble welding fumes to mice. Significant elevations in the absolute lymph node cell numbers for both B- and T-cells including the CD4(+) and CD8(+) subsets were observed. These results demonstrate that exposure to manual metal-stainless steel welding fumes is immunosuppressive in the presence of increased lymphoctye numbers in mice and raises concerns regarding the potential for adverse immunological effects to impact respiratory health in humans.

  6. Configuration and Calibration of High Temperature Furnaces for Testing Ceramic Matrix Composites

    DTIC Science & Technology

    2014-10-01

    Actual Furnace Cavity Stainless Steel Mesh Cage For Electrical Connections (both sides) High Temperature Power Lead Clamp Furnace Control TC’s Power... tests generate the basic properties such as modulus (E), ultimate tensile strength (UTS), proportional limit (PL), strain at failure (f), as well as...stress- strain behavior. Each material was tested at room temperature, at the maximum use temperature for the CMC system (as determined by the CMC

  7. Southwest view of rotary hearth furnace of the no. 2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Southwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  8. Northwest view of rotary hearth furnace of the no. 2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Northwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Skelp Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  9. Southwest view of rotary hearth furnace of the no. 2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Southwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Skelp Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  10. Northwest view of rotary hearth furnace of the no. 2 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Northwest view of rotary hearth furnace of the no. 2 seamless line in bays 17 and 18 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  11. Effect of basicity and reductant amount in the nickel pig iron (NPI) production from Indonesian limonite ore in submerged electric arc furnace (SAF)

    NASA Astrophysics Data System (ADS)

    Astuti, W.; Andika, R.; Nurjaman, F.

    2018-01-01

    The effect of basicity and reductant amount on the nickel and iron recovery of the nickel pig iron (NPI) production from Indonesian limonite ore was investigated in the experimental study using submerged electric arc furnace (SAF). Indonesian limonite ore used in this study originated from Sulawesi Island with the composition of Ni (1.26%) and Fe (43%). Metallurgical coke was applied as the reductant. This study showed that the the highest nickel and iron recovery as well as metal yield can be resulted from the basicity of 0.8 and reductant amount of 0.23 kg coke/kg limonite ore. Nickel content in the NPI produced was around 3 - 4%. It was concluded that this experiment can produce medium grade NPI.

  12. Recovery of titanium values from titanium grinding swarf by electric furnace smelting

    DOEpatents

    Gerdemann, Stephen J.; White, Jack C.

    1999-01-01

    A method for the recovery of valuable materials from titanium grinding swarf is provided comprising the steps of sieving the accumulated titanium grinding swarf to remove unwanted coarse trash and grinding wheel fragments, pelletizing, and smelting in an electric arc furnace to produce ferrotitanium and/or high titanium slag.

  13. Recovery of titanium values from titanium grinding swarf by electric furnace smelting

    DOEpatents

    Gerdemann, Stephen J.; White, Jack C.

    1998-01-01

    A method for the recovery of valuable materials from titanium grinding swarf is provided comprising the steps of sieving the accumulated titanium grinding swarf to remove unwanted coarse trash and grinding wheel fragments, pelletizing, and smelting in an electric arc furnace to produce ferrotitanium and/or high titanium slag.

  14. 15. TAKING A CAST AT FURNACE NO. 1 HOT SLAG, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. TAKING A CAST AT FURNACE NO. 1 HOT SLAG, BY-PRODUCT IN SMELTING OF PIG IRON, CAN BE SEEN FLOWING INTO THE SLAG YARD. VIEW IS LOOKING SOUTH. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  15. Double-Sided Single-Pass Submerged Arc Welding for 2205 Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Luo, Jian; Yuan, Yi; Wang, Xiaoming; Yao, Zongxiang

    2013-09-01

    The duplex stainless steel (DSS), which combines the characteristics of ferritic steel and austenitic steel, is used widely. The submerged arc welding (SAW) method is usually applied to join thick plates of DSS. However, an effective welding procedure is needed in order to obtain ideal DSS welds with an appropriate proportion of ferrite (δ) and austenite (γ) in the weld zone, particularly in the melted zone and heat-affected zone. This study evaluated the effectiveness of a high efficiency double-sided single-pass (DSSP) SAW joining method for thick DSS plates. The effectiveness of the converse welding procedure, characterizations of weld zone, and mechanical properties of welded joint are analyzed. The results show an increasing appearance and continuous distribution feature of the σ phase in the fusion zone of the leading welded seam. The converse welding procedure promotes the σ phase to precipitate in the fusion zone of leading welded side. The microhardness appears to significantly increase in the center of leading welded side. Ductile fracture mode is observed in the weld zone. A mixture fracture feature appears with a shear lip and tears in the fusion zone near the fusion line. The ductility, plasticity, and microhardness of the joints have a significant relationship with σ phase and heat treatment effect influenced by the converse welding step. An available heat input controlling technology of the DSSP formation method is discussed for SAW of thick DSS plates.

  16. Studies on microstructure, mechanical and pitting corrosion behaviour of similar and dissimilar stainless steel gas tungsten arc welds

    NASA Astrophysics Data System (ADS)

    Mohammed, Raffi; Dilkush; Srinivasa Rao, K.; Madhusudhan Reddy, G.

    2018-03-01

    In the present study, an attempt has been made to weld dissimilar alloys of 5mm thick plates i.e., austenitic stainless steel (316L) and duplex stainless steel (2205) and compared with that of similar welds. Welds are made with conventional gas tungsten arc welding (GTAW) process with two different filler wires namely i.e., 309L and 2209. Welds were characterized using optical microscopy to observe the microstructural changes and correlate with mechanical properties using hardness, tensile and impact testing. Potentio-dynamic polarization studies were carried out to observe the pitting corrosion behaviour in different regions of the welds. Results of the present study established that change in filler wire composition resulted in microstructural variation in all the welds with different morphology of ferrite and austenite. Welds made with 2209 filler showed plate like widmanstatten austenite (WA) nucleated at grain boundaries. Compared to similar stainless steel welds inferior mechanical properties was observed in dissimilar stainless steel welds. Pitting corrosion resistance is observed to be low for dissimilar stainless steel welds when compared to similar stainless steel welds. Overall study showed that similar duplex stainless steel welds having favorable microstructure and resulted in better mechanical properties and corrosion resistance. Relatively dissimilar stainless steel welds made with 309L filler obtained optimum combination of mechanical properties and pitting corrosion resistance when compared to 2209 filler and is recommended for industrial practice.

  17. Experimental study of the mechanical stabilization of electric arc furnace dust using fluid cement mortars.

    PubMed

    Ledesma, E F; Jiménez, J R; Ayuso, J; Fernández, J M; Brito, J de

    2017-03-15

    This article shows the results of an experimental study carried out in order to determine the maximum amount of electric arc furnace dust (EAFD) that can be incorporated into fluid cement-based mortars to produce mechanically stable monolithic blocks. The leaching performance of all mixes was studied in order to classify them according to the EU Council Decision 2003/33/EC. Two mortars were used as reference and three levels of EAFD incorporation were tested in each of the reference mortars. As the incorporation ratio of EAFD/cement increases, the mechanical strength decreases. This is due to the greater EAFD/cement and water/cement ratios, besides the presence of a double-hydrated hydroxide of Ca and Zn (CaZn 2 (OH) 6 ·2H 2 O) instead of the portlandite phase (Ca(OH) 2 ) in the mixes made with EAFD, as well as non-hydrated tricalcium silicate. A mass ratio of 2:1 (EAFD: cement-based mortar) can be added maintaining a stable mechanical strength. The mechanical stabilization process also reduced the leaching of metals, although it was not able to reduce the Pb concentration below the limit for hazardous waste. The high amount of EAFD mechanically stabilized in this experimental study can be useful to reduce the storage volume required in hazardous waste landfills. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Operating experience with 100% pellet burden on Amanda blast furnace

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keaton, D.E.; Minakawa, T.

    1993-01-01

    A number of significant changes in operations at the Ashland Works of the Armco Steel Company occurred in 1992 which directly impacted the Amanda Blast Furnace operation. These changes included the shutdown of the hot strip mill which resulted in coke oven gas enrichment of the Amanda stoves and an increase of 75 C in hot blast temperature, transition to 100% continuous cast operation which resulted in increased variation of the hot metal demand, and the July idling of the sinter plant. Historically, the Amanda Blast Furnace burden was 30% fluxed sinter and 70% acid pellet. It was anticipated thatmore » the change to 100% pellet burden would require changes in charging practice and alter furnace performance. The paper gives a general furnace description and then describes the burden characteristics, operating practice with 30% sinter/70% acid pellet burden, preparations for the 100% acid pellet burden operation, the 100% acid pellet operation, and the 100% fluxed pellet burden operation.« less

  19. Recovery of titanium values from titanium grinding swarf by electric furnace smelting

    DOEpatents

    Gerdemann, S.J.; White, J.C.

    1998-08-04

    A method for the recovery of valuable materials from titanium grinding swarf is provided comprising the steps of sieving the accumulated titanium grinding swarf to remove unwanted coarse trash and grinding wheel fragments, pelletizing, and smelting in an electric arc furnace to produce ferrotitanium and/or high titanium slag. 1 fig.

  20. Innovative Concept for the Recovery of Silver and Indium by a Combined Treatment of Jarosite and Electric Arc Furnace Dust

    NASA Astrophysics Data System (ADS)

    Wegscheider, S.; Steinlechner, S.; Leuchtenmüller, M.

    2017-02-01

    Industrial wastes such as slags, dust, or precipitation residues contain significant amounts of valuable metals like zinc, lead, and copper as well as precious metals like silver and indium. Nevertheless, a lot of these waste materials are not recycled, and therefore, many valuable metals end up being sent to landfills. Because of harmful components in the waste, it is often necessary to send it to specialized landfills for hazardous wastes, which leads to environmental problems as well as additional costs. Consequently, the recovery of the valuable metals from the residues represents a sensible task to decrease the negative impact on the environment and to reduce costs for maintaining a landfill. In addition, recycling helps to decrease the dependency from primary resources. The present study deals with the behavior of different metals in a pyro-metallurgical treatment for a mixture of jarosite and electric arc furnace dust with a special focus on indium and silver.

  1. 20. TAKING A CAST AT BLAST FURNACE NO. 1. WORKERS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. TAKING A CAST AT BLAST FURNACE NO. 1. WORKERS, LIKE THE ONE STANDING ON THE BRIDGE ABOVE THE 'BOTTLE' INTO WHICH THE HOT IRON FLOWS, ARE PROTECTED BY HEAVY FIREPROOF GARMENTS. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  2. TECHNOLOGY DEMONSTRATION SUMMARY. BABCOCK AND WILCOX CYCLONE FURNACE VITRIFICATION TECHNOLOGY (EPA/540/SR-92/017)

    EPA Science Inventory

    A Superfund Innovative Technology Evaluation (SITE) Demonstration of the Babcock & Wilcox Cyclone Furnace Vitrification Technology was conducted in November 1991. This Demonstration occurred at the Babcock & Wilcox (B&W) Alliance Research Center (ARC) in Alliance, OH. The B&W cyc...

  3. Microstructure and Mechanical Properties of Narrow Gap Laser-Arc Hybrid Welded 40 mm Thick Mild Steel.

    PubMed

    Zhang, Chen; Li, Geng; Gao, Ming; Zeng, XiaoYan

    2017-01-26

    Both laser-arc hybrid welding and narrow gap welding have potential for the fabrication of thick sections, but their combination has been seldom studied. In this research, 40 mm thick mild steel was welded by narrow gap laser-arc hybrid welding. A weld with smooth layer transition, free of visible defects, was obtained by nine passes at a 6 mm width narrow gap. The lower part of the weld has the lowest mechanical properties because of the lowest amount of acicular ferrite, but its ultimate tensile strength and impact absorbing energy is still 49% and 60% higher than those of base metal, respectively. The microhardness deviation of all filler layers along weld thickness direction is no more than 15 HV 0.2 , indicating that no temper softening appeared during multiple heat cycles. The results provide an alternative technique for improving the efficiency and quality of welding thick sections.

  4. Microstructure and Mechanical Properties of Narrow Gap Laser-Arc Hybrid Welded 40 mm Thick Mild Steel

    PubMed Central

    Zhang, Chen; Li, Geng; Gao, Ming; Zeng, XiaoYan

    2017-01-01

    Both laser-arc hybrid welding and narrow gap welding have potential for the fabrication of thick sections, but their combination has been seldom studied. In this research, 40 mm thick mild steel was welded by narrow gap laser-arc hybrid welding. A weld with smooth layer transition, free of visible defects, was obtained by nine passes at a 6 mm width narrow gap. The lower part of the weld has the lowest mechanical properties because of the lowest amount of acicular ferrite, but its ultimate tensile strength and impact absorbing energy is still 49% and 60% higher than those of base metal, respectively. The microhardness deviation of all filler layers along weld thickness direction is no more than 15 HV0.2, indicating that no temper softening appeared during multiple heat cycles. The results provide an alternative technique for improving the efficiency and quality of welding thick sections. PMID:28772469

  5. GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 BLAST FURNACE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW FROM THE SOUTHWEST, SHOWING THE #2 BLAST FURNACE IN THE RIGHT; THE CENTRAL COMPLEX WITH STOVES IN THE CENTER. ELECTRICAL POWER HOUSE IS ON THE LEFT BEYOND THE CONVEYOR LIFT. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  6. The determination of micro-arc plasma composition and properties of nanoparticles formed during cathodic plasma electrolysis of 304 stainless steel

    NASA Astrophysics Data System (ADS)

    Jovović, Jovica; Stojadinović, Stevan; Vasilić, Rastko; Tadić, Nenad; Šišović, Nikola M.

    2017-05-01

    This paper presents the research focused on the determination of micro-arc plasma composition during cathodic plasma electrolysis of AISI304 stainless steel in water solution of sodium hydroxide. The complex line shape of several Fe I spectral lines was observed and, by means of a dedicated fitting procedure based on the spectral line broadening theory and H2O thermal decomposition data, the mole fraction of micro-arc plasma constituents (H2, Fe, O, H, H2O, and OH) was determined. Subsequent characterization of the cathodic plasma electrolysis product formed during the process revealed that it consists of Fe-nanoparticles with median diameter of approximately 60 nm.

  7. Controlling electrode gap during vacuum arc remelting at low melting current

    DOEpatents

    Williamson, Rodney L.; Zanner, Frank J.; Grose, Stephen M.

    1997-01-01

    An apparatus and method for controlling electrode gap in a vacuum arc remelting furnace, particularly at low melting currents. Spectrographic analysis is performed of the metal vapor plasma, from which estimates of electrode gap are derived.

  8. Method for treating waste containing stainless steel

    DOEpatents

    Kujawa, Stephan T.; Battleson, Daniel M.; Rademacher, Jr., Edward L.; Cashell, Patrick V.; Filius, Krag D.; Flannery, Philip A.; Whitworth, Clarence G.

    1999-01-01

    A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe.sub.3 O.sub.4. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe.sub.2 O.sub.3. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater.

  9. Method for treating waste containing stainless steel

    DOEpatents

    Kujawa, S.T.; Battleson, D.M.; Rademacher, E.L. Jr.; Cashell, P.V.; Filius, K.D.; Flannery, P.A.; Whitworth, C.G.

    1999-03-02

    A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe{sub 3}O{sub 4}. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe{sub 2}O{sub 3}. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater. 3 figs.

  10. Progress on Protection of Titanium-Bearing Materials in Chinese Blast Furnace

    NASA Astrophysics Data System (ADS)

    Cai, Qiuye; Zhang, Jianliang; Jiao, Kexin; Wang, Cui

    Prolonging the campaign life of the blast furnace has been an important task for iron makers, and it has been studied for decades. Adding titanium-bearing materials is a generally agreed and effective technique to protect the blast furnace hearth. Titanium from titania additions in the burden or tuyere injection react with carbon and nitrogen and form scaffolds on the hearth surface to protect the hearth from subsequent erosion. In this article, the progress on blast furnace hearth protection of titania additions in Chinese steel companies and research institutions is investigated, and the difficulties in the operation and production, such as little effect after adding titanium- bearing materials and the property deterioration of liquid iron and slags, are analyzed. The future research for protection in Chinese blast furnace is proposed, and a comprehensive process which combines protection of titanium bearing materials with reasonable thermal balance and slag- making regimes should be established.

  11. Study of Mechanical Properties and Characterization of Pipe Steel welded by Hybrid (Friction Stir Weld + Root Arc Weld) Approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lim, Yong Chae; Sanderson, Samuel; Mahoney, Murray

    Friction stir welding (FSW) has recently attracted attention as an alternative construction process for gas/oil transportation applications due to advantages compared to fusion welding techniques. A significant advantage is the ability of FSW to weld the entire or nearly the entire wall thickness in a single pass, while fusion welding requires multiple passes. However, when FSW is applied to a pipe or tube geometry, an internal back support anvil is required to resist the plunging forces exerted during FSW. Unfortunately, it may not be convenient or economical to use internal backing support due to limited access for some applications. Tomore » overcome this issue, ExxonMobil recently developed a new concept, combining root arc welding and FSW. That is, a root arc weld is made prior to FSW that supports the normal loads associated with FSW. In the present work, mechanical properties of a FSW + root arc welded pipe steel are reported including microstructure and microhardness.« less

  12. Mechanical Characteristics of Submerged Arc Weldment in API Gas Pipeline Steel of Grade X65

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hashemi, S. H.; Mohammadyani, D.

    The mechanical properties of submerged arc weldment (SAW) in gas transportation pipeline steel of grade API X65 (65 ksi yield strength) were investigated. This steel is produced by thermo mechanical control rolled (TMC), and is largely used in Iran gas piping systems and networks. The results from laboratory study on three different regions; i.e. base metal (BM), fusion zone (FZ) and heat affected zone (HAZ) were used to compare weldment mechanical characteristics with those specified by API 5L (revision 2004) standard code. Different laboratory experiments were conducted on test specimens taken from 48 inch outside diameter and 14.3 mm wallmore » thickness gas pipeline. The test results showed a gradient of microstructure and Vickers hardness data from the centerline of FZ towards the unaffected MB. Similarly, lower Charpy absorbed energy (compared to BM) was observed in the FZ impact specimens. Despite this, the API specifications were fulfilled in three tested zones, ensuring pipeline structural integrity under working conditions.« less

  13. Increase of chromium yield by slag reduction during production of chromium steels

    NASA Astrophysics Data System (ADS)

    Bažan, J.; Socha, L.; Kurka, V.; Jonšta, P.; Sušovský, M.

    2017-02-01

    The paper is focused on the evaluation of the course of Cr2O3 reduction from slag to alloyed steel under laboratory conditions. The experiments were aimed at the evaluation of increase in the chromium content in the melt together with the studying the behaviour of Cr2O3 and the mechanism of reduction by means of three reducing agents. Anthracite, ferrosilicon and mixtures of anthracite and ferrosilicon belong among the selected reducing agents. The experimental melts were focused on the proposal of a theoretical calculation of the consumption of selected reducing agents, study of reduction under laboratory conditions at application of alloyed steel with content of chromium of 12.16 wt. %, temperatures of 1600 °C and 1650 °C, together with the change of amount of reducing agents and reduction time. The results indicated in the paper constitute basic information on the possibilities of Cr2O3 reduction from slag; they will be used for verification of results in the pilot plant and operation experiments which will simulate operating conditions in the electric arc furnace.

  14. INTERIOR VIEW OF TRANSFORMER ROOM FOR FURNACE NO. 2 LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF TRANSFORMER ROOM FOR FURNACE NO. 2 LOOKING SOUTHEAST, SHOWING BACK OF CONTROL PANEL AND TRANSFORMER (GE, 3000 KUA water cooled, 60 cycles, U.S. patent 1900585. Transformer dates from 1937, control panel GE resistors) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  15. 7. COPY OF 1947 PHOTOGRAPH LABELED 'VIEW OF BLAST FURNACES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. COPY OF 1947 PHOTOGRAPH LABELED 'VIEW OF BLAST FURNACES AND ORE DOCKS AT CORRIGAN MCKINNEY WORKS.' BROWNHOIST ORE BRIDGE, REECTED C. 1912 IS AT RIGHT. VIEW LOOKING NORTH. PHOTO COURTESY CLEVELAND PICTURE, COLLECTION, PUBLIC LIBRARY. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  16. Analytical Modeling of Plasma Arc Cutting of Steel Plate

    NASA Astrophysics Data System (ADS)

    Cimbala, John; Fisher, Lance; Settles, Gary; Lillis, Milan

    2000-11-01

    A transferred-arc plasma torch cuts steel plate, and in the process ejects a molten stream of iron and ferrous oxides ("ejecta"). Under non-optimum conditions - especially during low speed cuts and/or small-radius corner cuts - "dross" is formed. Dross is re-solidified molten metal that sticks to the underside of the cut and renders it rough. The present research is an attempt to analytically model this process, with the goal of predicting dross formation. With the aid of experimental data, a control volume formulation is used in a steady frame of reference to predict the mass flow of molten material inside the cut. Although simple, the model is three-dimensional, can predict the shear stress driving the molten material in the direction of the plasma jet, and can predict the velocity of molten material exiting the bottom of the plate. In order to predict formation of dross, a momentum balance is performed on the flowing melt, considering the resisting viscous and surface tension forces. Preliminary results are promising, and provide a potential means of predicting dross formation without resorting to detailed computational analyses.

  17. Automated information system for analysis and prediction of production situations in blast furnace plant

    NASA Astrophysics Data System (ADS)

    Lavrov, V. V.; Spirin, N. A.

    2016-09-01

    Advances in modern science and technology are inherently connected with the development, implementation, and widespread use of computer systems based on mathematical modeling. Algorithms and computer systems are gaining practical significance solving a range of process tasks in metallurgy of MES-level (Manufacturing Execution Systems - systems controlling industrial process) of modern automated information systems at the largest iron and steel enterprises in Russia. This fact determines the necessity to develop information-modeling systems based on mathematical models that will take into account the physics of the process, the basics of heat and mass exchange, the laws of energy conservation, and also the peculiarities of the impact of technological and standard characteristics of raw materials on the manufacturing process data. Special attention in this set of operations for metallurgic production is devoted to blast-furnace production, as it consumes the greatest amount of energy, up to 50% of the fuel used in ferrous metallurgy. The paper deals with the requirements, structure and architecture of BF Process Engineer's Automated Workstation (AWS), a computer decision support system of MES Level implemented in the ICS of the Blast Furnace Plant at Magnitogorsk Iron and Steel Works. It presents a brief description of main model subsystems as well as assumptions made in the process of mathematical modelling. Application of the developed system allows the engineering and process staff to analyze online production situations in the blast furnace plant, to solve a number of process tasks related to control of heat, gas dynamics and slag conditions of blast-furnace smelting as well as to calculate the optimal composition of blast-furnace slag, which eventually results in increasing technical and economic performance of blast-furnace production.

  18. Microstructure and fatigue resistance of high strength dual phase steel welded with gas metal arc welding and plasma arc welding processes

    NASA Astrophysics Data System (ADS)

    Ahiale, Godwin Kwame; Oh, Yong-Jun; Choi, Won-Doo; Lee, Kwang-Bok; Jung, Jae-Gyu; Nam, Soo Woo

    2013-09-01

    This study presents the microstructure and high cycle fatigue performance of lap shear joints of dual phase steel (DP590) welded using gas metal arc welding (GMAW) and plasma arc welding (PAW) processes. High cycle fatigue tests were conducted on single and double lap joints under a load ratio of 0.1 and a frequency of 20 Hz. In order to establish a basis for comparison, both weldments were fabricated to have the same weld depth in the plate thickness. The PAW specimens exhibited a higher fatigue life, a gentle S-N slope, and a higher fatigue limit than the GMAW specimens. The improvement in the fatigue life of the PAW specimens was primarily attributed to the geometry effect that exhibited lower and wider beads resulting in a lower stress concentration at the weld toe where cracks initiate and propagate. Furthermore, the microstructural constituents in the heat-affected zone (HAZ) of the PAW specimens contributed to the improvement. The higher volume fraction of acicular ferrite in the HAZ beneath the weld toe enhanced the PAW specimen's resistance to fatigue crack growth. The double lap joints displayed a higher fatigue life than the single lap joints without changing the S-N slope.

  19. Evolution of weld metal microstructure in shielded metal arc welding of X70 HSLA steel with cellulosic electrodes: A case study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ghomashchi, Reza, E-mail: reza.ghomashchi@adelaide.edu.au; Costin, Walter; Kurji, Rahim

    2015-09-15

    The microstructure of weld joint in X70 line pipe steel resulted from shielded metal arc welding with E6010 cellulosic electrodes is characterized using optical and electron microscopy. A range of ferritic morphologies have been identified ranging from polygonal inter- and intra-prior austenite grains allotriomorphic, idiomorphic ferrites to Widmanstätten, acicular and bainitic ferrites. Electron Backscatter Diffraction (EBSD) analysis using Image Quality (IQ) and Inverse Pole Figure (IPF) maps through superimposition of IQ and IPF maps and measurement of percentages of high and low angle grain boundaries was identified to assist in differentiation of acicular ferrite from Widmanstätten and bainitic ferrite morphologies.more » In addition two types of pearlitic structures were identified. There was no martensite detected in this weld structure. The morphology, size and chemistry of non-metallic inclusions are also discussed briefly. - Highlights: • Application of EBSD reveals orientation relationships in a range of phases for shielded metal arc welding of HSLA steel. • Nucleation sites of various ferrite morphologies identified • Formation of upper and lower bainite and their morphologies.« less

  20. Recycling of Malaysia's electric arc furnace (EAF) slag waste into heavy-duty green ceramic tile.

    PubMed

    Teo, Pao-Ter; Anasyida, Abu Seman; Basu, Projjal; Nurulakmal, Mohd Sharif

    2014-12-01

    Recently, various solid wastes from industry such as glass waste, fly ash, sewage sludge and slag have been recycled into various value-added products such as ceramic tile. The conventional solutions of dumping the wastes in landfills or incineration, including in Malaysia are getting obsolete as the annual huge amount of the solid wastes would boost-up disposal cost and may cause permanent damage to the flora and fauna. This recent waste recycling approach is much better and greener as it can resolve problems associated with over-limit storage of industrial wastes and reduce exploration of natural resources for ceramic tile to continuously sustain the nature. Therefore, in this project, an attempt was made to recycle electric arc furnace (EAF) slag waste, obtained from Malaysia's steel making industry, into ceramic tile via conventional powder compaction method. The research work was divided into two stages. The first stage was to evaluate the suitability of EAF slag in ceramic tile by varying weight percentage of EAF slag (40 wt.%, 50 wt.% and 60 wt.%) and ball clay (40 wt.%, 50 wt.% and 60 wt.%), with no addition of silica and potash feldspar. In the second stage, the weight percentage of EAF slag was fixed at 40 wt.% and the percentage of ball clay (30 wt.% and 40 wt.%), feldspar (10 wt.% and 20 wt.%) and silica (10 wt.% and 20 wt.%) added was varied accordingly. Results obtained show that as weight percentage of EAF slag increased up to 60 wt.%, the percentage of apparent porosity and water absorption also rose, with a reduction in tile flexural strength and increased porosity. On the other hand, limiting the weight percentage of EAF slag to 40 wt.% while increasing the weight percentage of ball clay led to a higher total percentage of anorthite and wollastonite minerals, resulting in higher flexural strength. It was found that introduction of silica and feldspar further improved the flexural strength due to optimization of densification process. The highest

  1. Protection of Reinforced Concrete Structures of Waste Water Treatment Reservoirs with Stainless Steel Coating Using Arc Thermal Spraying Technique in Acidified Water

    PubMed Central

    Lee, Han-Seung; Park, Jin-Ho; Singh, Jitendra Kumar; Ismail, Mohamed A.

    2016-01-01

    Waste water treatment reservoirs are contaminated with many hazardous chemicals and acids. Reservoirs typically comprise concrete and reinforcement steel bars, and the main elements responsible for their deterioration are hazardous chemicals, acids, and ozone. Currently, a variety of techniques are being used to protect reservoirs from exposure to these elements. The most widely used techniques are stainless steel plating and polymeric coating. In this study, a technique known as arc thermal spraying was used. It is a more convenient and economical method for protecting both concrete and reinforcement steel bar from deterioration in waste water treatment reservoirs. In this study, 316L stainless steel coating was applied to a concrete surface, and different electrochemical experiments were performed to evaluate the performance of coatings in different acidic pH solutions. The coating generated from the arc thermal spraying process significantly protected the concrete surface from corrosion in acidic pH solutions, owing to the formation of a double layer capacitance—a mixture of Cr3+ enriched with Cr2O3 and Cr-hydroxide in inner and Fe3+ oxide on the outer layer of the coating. The formation of this passive film is defective owing to the non-homogeneous 316L stainless steel coating surface. In the pH 5 solution, the growth of a passive film is adequate due to the presence of un-dissociated water molecules in the aqueous sulfuric acid solution. The coated surface is sealed with alkyl epoxide, which acts as a barrier against the penetration of acidic solutions. This coating exhibits higher impedance values among the three studied acidic pH solutions. PMID:28773875

  2. Protection of Reinforced Concrete Structures of Waste Water Treatment Reservoirs with Stainless Steel Coating Using Arc Thermal Spraying Technique in Acidified Water.

    PubMed

    Lee, Han-Seung; Park, Jin-Ho; Singh, Jitendra Kumar; Ismail, Mohamed A

    2016-09-03

    Waste water treatment reservoirs are contaminated with many hazardous chemicals and acids. Reservoirs typically comprise concrete and reinforcement steel bars, and the main elements responsible for their deterioration are hazardous chemicals, acids, and ozone. Currently, a variety of techniques are being used to protect reservoirs from exposure to these elements. The most widely used techniques are stainless steel plating and polymeric coating. In this study, a technique known as arc thermal spraying was used. It is a more convenient and economical method for protecting both concrete and reinforcement steel bar from deterioration in waste water treatment reservoirs. In this study, 316L stainless steel coating was applied to a concrete surface, and different electrochemical experiments were performed to evaluate the performance of coatings in different acidic pH solutions. The coating generated from the arc thermal spraying process significantly protected the concrete surface from corrosion in acidic pH solutions, owing to the formation of a double layer capacitance-a mixture of Cr 3+ enriched with Cr₂O₃ and Cr-hydroxide in inner and Fe 3+ oxide on the outer layer of the coating. The formation of this passive film is defective owing to the non-homogeneous 316L stainless steel coating surface. In the pH 5 solution, the growth of a passive film is adequate due to the presence of un-dissociated water molecules in the aqueous sulfuric acid solution. The coated surface is sealed with alkyl epoxide, which acts as a barrier against the penetration of acidic solutions. This coating exhibits higher impedance values among the three studied acidic pH solutions.

  3. Mercury mass flow in iron and steel production process and its implications for mercury emission control.

    PubMed

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Gao, Wei; Wu, Qingru; Hao, Jiming

    2016-05-01

    The iron and steel production process is one of the predominant anthropogenic sources of atmospheric mercury emissions worldwide. In this study, field tests were conducted to study mercury emission characteristics and mass flows at two iron and steel plants in China. It was found that low-sulfur flue gas from sintering machines could contribute up to 41% of the total atmospheric mercury emissions, and desulfurization devices could remarkably help reduce the emissions. Coal gas burning accounted for 17%-49% of the total mercury emissions, and therefore the mercury control of coal gas burning, specifically for the power plant burning coal gas to generate electricity, was significantly important. The emissions from limestone and dolomite production and electric furnaces can contribute 29.3% and 4.2% of the total mercury emissions from iron and steel production. More attention should be paid to mercury emissions from these two processes. Blast furnace dust accounted for 27%-36% of the total mercury output for the whole iron and steel production process. The recycling of blast furnace dust could greatly increase the atmospheric mercury emissions and should not be conducted. The mercury emission factors for the coke oven, sintering machine and blast furnace were 0.039-0.047gHg/ton steel, and for the electric furnace it was 0.021gHg/ton steel. The predominant emission species was oxidized mercury, accounting for 59%-73% of total mercury emissions to air. Copyright © 2016. Published by Elsevier B.V.

  4. 3-D Transient Heat Transfer Analysis of Slab Heating Characteristics in a Reheating Furnace in Hot Strip Mills

    NASA Astrophysics Data System (ADS)

    Jang, J. Y.; Lee, Y. W.; Lin, C. N.; Wang, C. H.

    2016-05-01

    A three-dimensional mathematical transient heat transfer model for the prediction of temperature distribution within the slab has been developed by considering the thermal radiation in the walking-beam-type reheating furnace chamber. The steel slabs are heated up through the non-firing, preheating, 1st-heating, 2nd-heating, and soaking zones in the furnace, respectively, where the furnace wall temperature is function of time. Comparison with the in-situ experimental data from Steel Company in Taiwan shows that the present heat transfer model works well for the prediction of thermal behavior of the slab in the reheating furnace. The effects of different skid button height (H=60mm, 90mm, and 120mm) and different gap distance between two slabs (S=50mm, 75mm, and 100mm) on the slab skid mark formation and temperature profiles are investigated. It is found that the skid mark severity decreases with an increase in the skid button height. The effect of gap distance is important only for the slab edge planes, while it is insignificant for the slab central planes.

  5. Surface preparation effects on GTA (gas tungsten arc) weld penetration in JBK-75 stainless steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campbell, R.D.; Heiple, C.R.; Sturgill, P.L.

    1989-01-01

    The results of a study are reported here on the effects of surface preparation on the shape of GTA welds on JBK-75, an austenitic precipitation hardenable stainless steel similar to A286. Minor changes in surface (weld groove) preparation produced substantial changes in the penetration characteristics and welding behavior of this alloy. Increased and more consistent weld penetration (higher d/w ratios) along with improved arc stability and less arc wander result from wire brushing and other abrasive surface preparations, although chemical and machining methods did not produce any improvement in penetration. Abrasive treatments roughen the surface, increase the surface area, andmore » increase the surface oxide thickness. The increased weld d/w ratio is attributed to oxygen added to the weld pool from the surface oxide on the base metal. The added oxygen alters the surface-tension driven fluid flow pattern in the weld pool. Similar results were observed with changes in filler wire surface oxide thickness, caused by changes in wire production conditions. 15 refs., 14 figs., 4 tabs.« less

  6. Development of a Hot Working Steel Based on a Controlled Gas-Metal-Reaction

    NASA Astrophysics Data System (ADS)

    Ritzenhoff, Roman; Gharbi, Mohammad Malekipour

    As a result of cost sensitiveness, the demand on hot working steels with advanced characteristics and properties are ascending. We have used a controlled gas-metal-reaction in a P-ESR furnace to produce high quality hot working steel. These types of materials are also known as High Nitrogen Steels (HNS). An overview of the development in a pressurized induction furnace to the final industrial scale using P-ESR will be provided. Different heat treatment strategies are conducted and their effect on mechanical properties is investigated.

  7. Chem I Supplement: Chemistry of Steel Making.

    ERIC Educational Resources Information Center

    Sellers, Neal

    1980-01-01

    Provides information about the chemistry of steel making applicable to teaching secondary school science. Generalized chemical reactions describe the manufacture of steel from iron ore. Also discussed are raw materials, processing choices, and how various furnaces (blast, direct reduction, open hearth, basic oxygen, electric) work. (CS)

  8. Controlling electrode gap during vacuum arc remelting at low melting current

    DOEpatents

    Williamson, R.L.; Zanner, F.J.; Grose, S.M.

    1997-04-15

    An apparatus and method are disclosed for controlling electrode gap in a vacuum arc remelting furnace, particularly at low melting currents. Spectrographic analysis is performed of the metal vapor plasma, from which estimates of electrode gap are derived. 5 figs.

  9. Recovery Act: ArcelorMittal USA Blast Furnace Gas Flare Capture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seaman, John

    2013-01-14

    The U.S. Department of Energy (DOE) awarded a financial assistance grant under the American Recovery and Reinvestment Act of 2009 (Recovery Act) to ArcelorMittal USA, Inc. (ArcelorMittal) for a project to construct and operate a blast furnace gas recovery boiler and supporting infrastructure at ArcelorMittal’s Indiana Harbor Steel Mill in East Chicago, Indiana. Blast furnace gas (BFG) is a by-product of blast furnaces that is generated when iron ore is reduced with coke to create metallic iron. BFG has a very low heating value, about 1/10th the heating value of natural gas. BFG is commonly used as a boiler fuel;more » however, before installation of the gas recovery boiler, ArcelorMittal flared 22 percent of the blast furnace gas produced at the No. 7 Blast Furnace at Indiana Harbor. The project uses the previously flared BFG to power a new high efficiency boiler which produces 350,000 pounds of steam per hour. The steam produced is used to drive existing turbines to generate electricity and for other requirements at the facility. The goals of the project included job creation and preservation, reduced energy consumption, reduced energy costs, environmental improvement, and sustainability.« less

  10. Fabrication and characterization of microstructure of stainless steel matrix composites containing up to 25 vol% NbC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kan, Wen Hao, E-mail: wkan6795@uni.sydney.edu.au

    AISI 440 stainless steels reinforced with various volume fractions of niobium carbide (NbC) particles of up to 25 vol% were fabricated in-situ using an argon arc furnace and then heat-treated to produce a martensitic matrix. Optical and scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and electron back-scatter diffraction (EBSD) techniques were used to analyze the microstructure, phases and composition of these composites. Interestingly, it was found that Chinese-script NbC could nucleate on existing primary NbC particles creating NbC clusters with complex microstructures. Additionally, hardness tests were used to evaluate viability in mining and mineral processing applications. The increasemore » in NbC content resulted in an overall increase in the hardness of the composites while causing a marginal decrease in the amount of Cr in solid solution with the matrix, which could be a concern for corrosion resistance. The latter was due to the fact that the NbC lattice could dissolve a minor amount of Cr. Thermodynamic simulations also attributed this to a slight increase in M{sub 7}C{sub 3} precipitation. Nonetheless, these novel composites show great promise for applications in wear and corrosive environments. - Highlights: •Stainless steels reinforced with NbC particles of up to 25 vol% were fabricated. •NbC was formed in-situ in the steels using an arc melter. •Martensitic transformation of the matrix of each sample was achieved. •NbC reinforcements increased the bulk hardness values of the steels. •Dissolved Cr in the matrix of each sample was sufficient for passivity in theory.« less

  11. Liquid-Arc/Spark-Excitation Atomic-Emission Spectroscopy

    NASA Technical Reports Server (NTRS)

    Schlagen, Kenneth J.

    1992-01-01

    Constituents of solutions identified in situ. Liquid-arc/spark-excitation atomic-emission spectroscopy (LAES) is experimental variant of atomic-emission spectroscopy in which electric arc or spark established in liquid and spectrum of light from arc or spark analyzed to identify chemical elements in liquid. Observations encourage development of LAES equipment for online monitoring of process streams in such industries as metal plating, electronics, and steel, and for online monitoring of streams affecting environment.

  12. Arc-Free High-Power dc Switch

    NASA Technical Reports Server (NTRS)

    Miller, W. N.; Gray, O. E.

    1982-01-01

    Hybrid switch allows high-power direct current to be turned on and off without arcing or erosion. Switch consists of bank of transistors in parallel with mechanical contacts. Transistor bank makes and breaks switched circuit; contacts carry current only during steady-state "on" condition. Designed for Space Shuttle orbiter, hybrid switch can be used also in high-power control circuits in aircraft, electric autos, industrial furnaces, and solar-cell arrays.

  13. Behaviour of the iron vapour core in the arc of a controlled short-arc GMAW process with different shielding gases

    NASA Astrophysics Data System (ADS)

    Wilhelm, G.; Kozakov, R.; Gött, G.; Schöpp, H.; Uhrlandt, D.

    2012-02-01

    The controlled metal transfer process (CMT) is a variation of the gas metal arc welding (GMAW) process which periodically varies wire feeding speed. Using a short-arc burning phase to melt the wire tip before the short circuit, heat input to the workpiece is reduced. Using a steel wire and a steel workpiece, iron vapour is produced in the arc, its maximum concentration lying centrally. The interaction of metal vapour and welding gas considerably impacts the arc profile and, consequently, the heat transfer to the weldpool. Optical emission spectroscopy has been applied to determine the radial profiles of the plasma temperature and iron vapour concentration, as well as their temporal behaviour in the arc period for different mixtures of Ar, O2 and CO2 as shielding gases. Both the absolute iron vapour density and the temporal expansion of the iron core differ considerably for the gases Ar + 8%O2, Ar + 18% CO2 and 100% CO2 respectively. Pronounced minimum in the radial temperature profile is found in the arc centre in gas mixtures with high Ar content under the presence of metal vapour. This minimum disappears in pure CO2 gas. Consequently, the temperature and electrical and thermal conductivity in the arc when CO2 is used as a shielding gas are considerably lower.

  14. Influence of Deposition Conditions on Fatigue Properties of Martensitic Stainless Steel with Tin Film Coated by Arc Ion Plating Method

    NASA Astrophysics Data System (ADS)

    Fukui, Satoshi; Yonekura, Daisuke; Murakami, Ri-Ichi

    The surface properties like roughness etc. strongly influence the fatigue strength of high-tensile steel. To investigate the effect of surface condition and TiN coating on the fatigue strength of high-strength steel, four-point bending fatigue tests were carried out for martensitic stainless steel with TiN film coated using arc ion plating (AIP) method. This study, using samples that had been polished under several size of grind particle, examines the influence of pre-coating treatment on fatigue properties. A 2-µm-thick TiN film was deposited onto the substrate under three kinds of polishing condition. The difference of the hardness originated in the residual stress or thin deformation layer where the difference of the size of grinding particle of the surface polishing. And it leads the transformation of the interface of the substrate and the TiN film and improves fatigue limit.

  15. Experimental Study on the Electrochemical Anti-Corrosion Properties of Steel Structures Applying the Arc Thermal Metal Spraying Method

    PubMed Central

    Choe, Hong-Bok; Lee, Han-Seung; Shin, Jun-Ho

    2014-01-01

    The arc thermal metal spraying method (ATMSM) provides proven long-term protective coating systems using zinc, aluminum and their alloys for steel work in a marine environment. This paper focuses on studying experimentally the anti-corrosion criteria of ATMSM on steel specimens. The effects of the types of spraying metal and the presence or absence of sealing treatment from the thermal spraying of film on the anti-corrosion performance of TMSM were quantitatively evaluated by electrochemical techniques. The results showed that ATMSM represented a sufficient corrosion resistance with the driving force based on the potential difference of more than approximately 0.60 V between the thermal spraying layer and the base substrate steel. Furthermore, it was found that the sealing treatment of specimens had suppressed the dissolution of metals, increased the corrosion potential, decreased the corrosion current density and increased the polarization resistance. Metal alloy Al–Mg (95%:5%) by mass with epoxy sealing coating led to the most successful anti-corrosion performance in these electrochemical experiments. PMID:28788271

  16. INTERIOR VIEW, LOOKING SOUTHWEST, WITH PLASMA ARC BURNING MACHINE (GALT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW, LOOKING SOUTHWEST, WITH PLASMA ARC BURNING MACHINE (GALT INDUSTRIES) WHICH CUTS STEEL SHAPES AND OPERATOR PHILIP WILLOUBY. - O'Neal Steel, Incorporated, Fabrication Shop, 744 Forty-first Avenue North, Birmingham, Jefferson County, AL

  17. 54. STEEL COMPLEX FROM CLARK AVENUE BRIDGE, LOOKING NORTHEAST. FOUNDRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    54. STEEL COMPLEX FROM CLARK AVENUE BRIDGE, LOOKING NORTHEAST. FOUNDRY IN FOREGROUND, INGOT MOLDS ON TRACK AT RIGHT, BASIC OXYGEN FURNACE ON TRACK AT RIGHT. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

  18. Molybdate adsorption from steel slag eluates by subsoils.

    PubMed

    Matern, K; Rennert, T; Mansfeldt, T

    2013-11-01

    Steel slags are industrial by-products which are generated in large amounts worldwide, e.g. 150-230×10(6) Mg in 2012, and which are partly used for construction. Molybdenum (Mo) can be added during steel processing in order to harden the steel. The objective of this study was to evaluate the adsorption behaviour of molybdate (MoO4(2-)) from slag eluates in subsoils. Molybdate batch adsorption experiments were carried out with eluates obtained from two different kinds of steel slags (i) LD slag (Linz-Donawitz operation, LDS) and (ii) electric arc furnace slag (EAF) to assess the risk that may arise from the contamination of groundwater by the leaching of molybdate. Six different subsoils were chosen in order to provide a wide range of chemical properties (pH 4.0-7.6; dithionite-extractable Fe 0.73-14.7 g kg(-1)). Molybdate adsorption experiments were carried out at the pH of the steel slag eluates (pH 11-12) as well as at pH values adjusted to the soil pH. The data were evaluated with the Freundlich equation. Molybdate adsorption exhibited a maximum near pH 4 for steel slag eluates adjusted to the soil pH, and decreased rapidly with increasing pH until adsorption was virtually zero at pH>11. Adsorption was greater for soils with high amounts of dithionite-extractable Fe oxides. The extent and behaviour of molybdate adsorption from both eluates was similar. After a reaction time of 24h, the pH of the EAF slag eluate was lower than that of the LD steel slag eluate, which was caused by different acid buffer capacities. Some soils were able to decrease the pH of the EAF slag eluates by about 4 pH units, enhancing the adsorption of molybdate. Transport simulations indicated that molybdate discharge is low in acidic soils. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Steel refining possibilities in LF

    NASA Astrophysics Data System (ADS)

    Dumitru, M. G.; Ioana, A.; Constantin, N.; Ciobanu, F.; Pollifroni, M.

    2018-01-01

    This article presents the main possibilities for steel refining in Ladle Furnace (LF). These, are presented: steelmaking stages, steel refining through argon bottom stirring, online control of the bottom stirring, bottom stirring diagram during LF treatment of a heat, porous plug influence over the argon stirring, bottom stirring porous plug, analysis of porous plugs disposal on ladle bottom surface, bottom stirring simulation with ANSYS, bottom stirring simulation with Autodesk CFD.

  20. Surface Dynamics of Unipolar Arcing

    DTIC Science & Technology

    1989-12-01

    slioising bulk copper deposition. (6.4X)( i10 ) Figure 20. Copper deposition on a steel surface shoiing a cor relation bet’seeni greater pitting...pit’s depth and its width. 1. Arc damage - a heating phenomenon To study the effect of the same laser shot. and the same unipolar arc. on two...between pit depth and diameter for pitting on the copper films. This conclusion comes from the fact that in many cases pits with relatively smaller

  1. CHARGING SIDE OF #130 ELECTRIC FURNACE CO. REHEAT FURNACE IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CHARGING SIDE OF #130 ELECTRIC FURNACE CO. REHEAT FURNACE IN REROLL BAY. CAKES FROM THE CASTING SHOP ARE BROUGHT UP TO ROLLING TEMPERATURE IN ONE OF TWO (#130 AND 146) GAS-FIRED FURNACES. A RADIO-CONTROLLED OVERHEAD CRANE TRANSFERS CAKES FROM FLATCARS TO THE ROLLER LINE LEADING INTO THE FURNACE. CAKES ARE HEATED AT 900-1000 DEGREES FAHRENHEIT FOR THREE TO FOUR HOURS. RATED FURNACE CAPACITY IS 100,000 LBS.\\HOUR. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

  2. Effect of Heat Input on Geometry of Austenitic Stainless Steel Weld Bead on Low Carbon Steel

    NASA Astrophysics Data System (ADS)

    Saha, Manas Kumar; Hazra, Ritesh; Mondal, Ajit; Das, Santanu

    2018-05-01

    Among different weld cladding processes, gas metal arc welding (GMAW) cladding becomes a cost effective, user friendly, versatile method for protecting the surface of relatively lower grade structural steels from corrosion and/or erosion wear by depositing high grade stainless steels onto them. The quality of cladding largely depends upon the bead geometry of the weldment deposited. Weld bead geometry parameters, like bead width, reinforcement height, depth of penetration, and ratios like reinforcement form factor (RFF) and penetration shape factor (PSF) determine the quality of the weld bead geometry. Various process parameters of gas metal arc welding like heat input, current, voltage, arc travel speed, mode of metal transfer, etc. influence formation of bead geometry. In the current experimental investigation, austenite stainless steel (316) weld beads are formed on low alloy structural steel (E350) by GMAW using 100% CO2 as the shielding gas. Different combinations of current, voltage and arc travel speed are chosen so that heat input increases from 0.35 to 0.75 kJ/mm. Nine number of weld beads are deposited and replicated twice. The observations show that weld bead width increases linearly with increase in heat input, whereas reinforcement height and depth of penetration do not increase with increase in heat input. Regression analysis is done to establish the relationship between heat input and different geometrical parameters of weld bead. The regression models developed agrees well with the experimental data. Within the domain of the present experiment, it is observed that at higher heat input, the weld bead gets wider having little change in penetration and reinforcement; therefore, higher heat input may be recommended for austenitic stainless steel cladding on low alloy steel.

  3. INTERIOR VIEW SHOWING FURNACE KEEPER OBSERVING FURNACE THROUGH BLUE GLASS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW SHOWING FURNACE KEEPER OBSERVING FURNACE THROUGH BLUE GLASS EVERY TWENTY MINUTES TO DETERMINE SIZE AND TEXTURE OF BATCH AND OTHER VARIABLES. FAN IN FRONT COOLS WORKERS AS THEY CONDUCT REPAIRS. FURNACE TEMPERATURE AT 1572 DEGREES FAHRENHEIT. - Chambers-McKee Window Glass Company, Furnace No. 2, Clay Avenue Extension, Jeannette, Westmoreland County, PA

  4. Effect of Gas Tungsten Arc Welding Parameters on Hydrogen-Assisted Cracking of Type 321 Stainless Steel

    NASA Astrophysics Data System (ADS)

    Rozenak, Paul; Unigovski, Yaakov; Shneck, Roni

    2016-05-01

    The susceptibility of AISI type 321 stainless steel welded by the gas tungsten arc welding (GTAW) process to hydrogen-assisted cracking (HAC) was studied in a tensile test combined with in situ cathodic charging. Specimen charging causes a decrease in ductility of both the as-received and welded specimens. The mechanical properties of welds depend on welding parameters. For example, the ultimate tensile strength and ductility increase with growing shielding gas (argon) rate. More severe decrease in the ductility was obtained after post-weld heat treatment (PWHT). In welded steels, in addition to discontinuous grain boundary carbides (M23C6) and dense distribution of metal carbides MC ((Ti, Nb)C) precipitated in the matrix, the appearance of delta-ferrite phase was observed. The fracture of sensitized specimens was predominantly intergranular, whereas the as-welded specimens exhibited mainly transgranular regions. High-dislocation density regions and stacking faults were found in delta-ferrite formed after welding. Besides, thin stacking fault plates and epsilon-martensite were found in the austenitic matrix after the cathodic charging.

  5. Submerged Arc Stainless Steel Strip Cladding—Effect of Post-Weld Heat Treatment on Thermal Fatigue Resistance

    NASA Astrophysics Data System (ADS)

    Kuo, I. C.; Chou, C. P.; Tseng, C. F.; Lee, I. K.

    2009-03-01

    Two types of martensitic stainless steel strips, PFB-132 and PFB-131S, were deposited on SS41 carbon steel substrate by a three-pass submerged arc cladding process. The effects of post-weld heat treatment (PWHT) on thermal fatigue resistance and hardness were evaluated by thermal fatigue and hardness testing, respectively. The weld metal microstructure was investigated by utilizing optical microscopy, scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Results showed that, by increasing the PWHT temperature, hardness decreased but there was a simultaneous improvement in weldment thermal fatigue resistance. During tempering, carbide, such as (Fe, Cr)23C6, precipitated in the weld metals and molybdenum appeared to promote (Fe, Cr, Mo)23C6 formation. The precipitates of (Fe, Cr, Mo)23C6 revealed a face-centered cubic (FCC) structure with fine grains distributed in the microstructure, thereby effectively increasing thermal fatigue resistance. However, by adding nickel, the AC1 temperature decreased, causing a negative effect on thermal fatigue resistance.

  6. Hydrogen Cracking in Gas Tungsten Arc Welding of an AISI Type 321 Stainless Steel

    NASA Astrophysics Data System (ADS)

    Rozenak, P.; Unigovski, Ya.; Shneck, R.

    The effects of in situ cathodic charging on the tensile properties and susceptibility to cracking of an AISI type 321 stainless steel, welded by the gas tungsten arc welding (GTAW) process, was studied by various treatments. Appearance of delta-ferrite phase in the as-welded steels in our tested conditions was observed with discontinuous grain boundaries (M23C6) and a dense distribution of metal carbides MC ((Ti, Nb)C), which precipitated in the matrix. Shielding gas rates changes the mechanical properties of the welds. Ultimate tensile strength and ductility are increases with the resistance to the environments related the increase of the supplied shielding inert gas rates. Charged specimens, caused mainly in decreases in the ductility of welded specimens. However, more severe decrease in ductility was obtained after post weld heat treatment (PWHT). The fracture of sensitized specimens was predominantly intergranular, whereas the as-welded specimens exhibited massive transgranular regions. Both types of specimen demonstrated narrow brittle zones at the sides of the fracture surface and ductile micro-void coalescences in the middle. Ferrite δ was form after welding with high density of dislocation structures and stacking faults formation and the thin stacking fault plates with e-martensite phase were typically found in the austenitic matrix after the cathodical charging process.

  7. Stainless steel manual metal arc welding fumes in rats.

    PubMed Central

    Kalliomäki, P L; Lakomaa, E; Kalliomäki, K; Kiilunen, M; Kivelä, R; Vaaranen, V

    1983-01-01

    Forty two male Wistar rats were exposed to manual metal arc (MMA) stainless steel (SS) welding fumes generated by an automatic welding device for "nose-only" exposure. The exposure simulated an actual MMA/SS welding environment as closely as possible. For the retention study, the duration of exposure was one hour per workday for one, two, three, of four weeks and for the clearance study four weeks. The retention and clearance of the chromium, nickel, and iron found in MMA/SS welding fumes in the rats' lungs were studied as was the distribution of the metals to other organs. Instrumental neutron activation analysis (INAA) was used for the multi-element chemical activation analyses. The concentrations of chromium and nickel in the blood and the urine were determined by atomic absorption method (AAS). The retention of exogenous iron was determined by a magnetic measuring method. The results indicated that the lungs were the target organs of soluble hexavalent chromates. The half times of lung clearance for Cr, Ni, and Fe were 40 +/- 4 d, 20 +/- d, and 50 +/- 10 d. When the lung clearance curves are compared, the half times of Cr and Fe lung clearance are similar but nickel disappears faster. The distribution and clearance patterns of chromium to other organs differ from those obtained after single intravenous or intratracheal injections of alkaline chromates. PMID:6830723

  8. The effect of smelting time and composition of palm kernel shell charcoal reductant toward extractive Pomalaa nickel laterite ore in mini electric arc furnace

    NASA Astrophysics Data System (ADS)

    Sihotang, Iqbal Huda; Supriyatna, Yayat Iman; Ismail, Ika; Sulistijono

    2018-04-01

    Indonesia is a country that is rich in natural resources. Being a third country which has a nickel laterite ore in the world after New Caledonia and Philippines. However, the processing of nickel laterite ore to increase its levels in Indonesia is still lacking. In the processing of nickel laterite ore into metal, it can be processed by pyrometallurgy method that typically use coal as a reductant. However, coal is a non-renewable energy and have high enough levels of pollution. One potentially replace is the biomass, that is a renewable energy. Palm kernel shell are biomass that can be used as a reductant because it has a fairly high fix carbon content. This research aims to make nickel laterite ores become metal using palm kernel shell charcoal as reductant in mini electric arc furnace. The result show that the best smelting time of this research is 60 minutes with the best composition of the reductant is 2,000 gram.

  9. Mixing of multiple metal vapours into an arc plasma in gas tungsten arc welding of stainless steel

    NASA Astrophysics Data System (ADS)

    Park, Hunkwan; Trautmann, Marcus; Tanaka, Keigo; Tanaka, Manabu; Murphy, Anthony B.

    2017-11-01

    A computational model of the mixing of multiple metal vapours, formed by vaporization of the surface of an alloy workpiece, into the thermal arc plasma in gas tungsten arc welding (GTAW) is presented. The model incorporates the combined diffusion coefficient method extended to allow treatment of three gases, and is applied to treat the transport of both chromium and iron vapour in the helium arc plasma. In contrast to previous models of GTAW, which predict that metal vapours are swept away to the edge of the arc by the plasma flow, it is found that the metal vapours penetrate strongly into the arc plasma, reaching the cathode region. The predicted results are consistent with published measurements of the intensity of atomic line radiation from the metal vapours. The concentration of chromium vapour is predicted to be higher than that of iron vapour due to its larger vaporization rate. An accumulation of chromium vapour is predicted to occur on the cathode at about 1.5 mm from the cathode tip, in agreement with published measurements. The arc temperature is predicted to be strongly reduced due to the strong radiative emission from the metal vapours. The driving forces causing the diffusion of metal vapours into the helium arc are examined, and it is found that diffusion due to the applied electric field (cataphoresis) is dominant. This is explained in terms of large ionization energies and the small mass of helium compared to those of the metal vapours.

  10. Gravitational effects on weld pool shape and microstructural evolution during gas tungsten arc and laser beam welding on 304 stainless steel, nickel, and aluminum-4 wt.% copper alloy

    NASA Astrophysics Data System (ADS)

    Kang, Namhyun

    The objective of the present work was to investigate effects of gravitational (acceleration) level and orientation on Ni 200 alloy (99.5% Ni purity), 304 stainless steel, and Al-4 wt.% Cu alloy during gas tungsten arc welding (GTAW) and laser beam welding (LBW). Main characterization was focused on the weld pool shape, microstructure, and solute distribution as a function of gravitational level and orientation. The welds were divided into two classes, i.e., 'stable' and 'unstable' welds, in view of the variation of weld pool shape as a function of gravitational level and orientation. In general, higher arc current and translational GTAW produced more significant effects of gravitational orientation on the weld pool shape than the case of lower arc current and spot welding. Cross-sectional area (CSA) was a secondary factor in determining the stability of weld pool shape. For the 'stable' weld of 304 stainless steel GTAW, the II-U weld showed less convexity in the pool bottom and more depression of the free surface, therefore producing deeper penetration (10--20%) than the case of II-D weld. The II-D weld of 304 stainless steel showed 31% deeper penetration, 28% narrower width, and more hemispherical shape of the weld pool than the case of II-U weld. For GTAW on 304 stainless steel, gravitational level variation from low gravity (LG ≈ 1.2 go) to high gravity (HG ≈ 1.8 go) caused 10% increase in width and 10% decrease in depth while maintaining the overall weld pool volume. Furthermore, LBW on 304 stainless steels showed mostly constant shape of weld pool as a function of gravitational orientation. GTAW on Ni showed similar trends of weld pool shape compared with GTAW on 304 stainless steel, i.e., the weld pool became unstable by showing more penetration in the II-D weld for slower arc translational velocity (V a) and larger weld pool size. However, the Ni weld pool shape had greater stability of the weld pool shape with respect to the gravitational orientation

  11. High Temperature Corrosion and Characterization Studies in Flux Cored Arc Welded 2.25Cr-1Mo Power Plant Steel

    NASA Astrophysics Data System (ADS)

    Kumaresh Babu, S. P.; Natarajan, S.

    2010-07-01

    Higher productivity is registered with Flux cored arc welding (FCAW) process in many applications. Further, it combines the characteristics of shielded metal arc welding (SMAW), gas metal arc welding (GMAW), and submerged arc welding (SAW) processes. This article describes the experimental work carried out to evaluate and compare corrosion and its inhibition in SA 387 Gr.22 (2.25Cr-1Mo) steel weldments prepared by FCAW process with four different heat inputs exposed to hydrochloric acid medium at 0.1, 0.5, and 1.0 M concentrations. The parent metal, weld metal, and heat-affected zone are chosen as regions of exposure for the study carried out at 100 °C. Electrochemical polarization techniques such as Tafel line extrapolation (Tafel) and linear polarization resistance (LPR) have been used to measure the corrosion current. The role of hexamine and mixed inhibitor (thiourea + hexamine in 0.5 M HCl), each at 100 ppm concentration is studied in these experiments. Microstructural observation, hardness survey, surface characterization, and morphology using scanning electron microscope (SEM) and x-ray diffraction (XRD) have been made on samples to highlight the nature and extent of film formation. The film is found to contain Fe2Si, FeSi2, FeMn3, Fe7Mo3, Fe3O4, FeO, FeCr, AlO7Fe3SiO3, and KFe4Mn77Si19.

  12. Bioleaching of metals from steel slag by Acidithiobacillus thiooxidans culture supernatant.

    PubMed

    Hocheng, Hong; Su, Cheer; Jadhav, Umesh U

    2014-12-01

    The generation of 300–500 kg of slag per ton of the steel produced is a formidable amount of solid waste available for treatment. They usually contain considerable quantities of valuable metals. In this sense, they may become either important secondary resource if processed in eco-friendly manner for secured supply of contained metals or potential pollutants, if not treated properly. It is possible to recover metals from steel slag by applying bioleaching process. Electric arc furnace (EAF) slag sample was used for bioleaching of metals. In the present study, before bioleaching experiment water washing of an EAF slag was carried out. This reduced slag pH from 11.2 to 8.3. Culture supernatants of Acidithiobacillus thiooxidans (At. thiooxidans), Acidithiobacillus ferrooxidans (At. ferrooxidans), and Aspergillus niger (A. niger) were used for metal solubilization. At. thiooxidans culture supernatant containing 0.016 M sulfuric acid was found most effective for bioleaching of metals from an EAF slag. Maximum metal extraction was found for Mg (28%), while it was least for Mo (0.1%) in six days. Repeated bioleaching cycles increased metal recovery from 28% to 75%, from 14% to 60% and from 11% to 27%, for Mg, Zn and Cu respectively.

  13. Development of Chromium-Free Welding Consumables for Stainless Steels

    DTIC Science & Technology

    2009-02-01

    FINAL REPORT Development of Chromium -Free Welding Consumables for Stainless Steels SERDP Project WP-1415 FEBRUARY 2009 J.C. Lippold...NUMBER 4. TITLE AND SUBTITLE Development of Chromium -Free Welding Consumables for Stainless Steels 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...Energy dispersive spectroscopy FGR Fume generation rate GMAW Gas metal arc welding GTAW Gas tungsten arc welding HAZ Heat affected zone LTE Long

  14. Control of exposure to hexavalent chromium and ozone in gas metal arc welding of stainless steels by use of a secondary shield gas.

    PubMed

    Dennis, John H; French, Michael J; Hewitt, Peter J; Mortazavi, Seyed B; Redding, Christopher A J

    2002-01-01

    Previous work has demonstrated that the shield gas composition in gas metal arc welding can have a considerable effect on hexavalent chromium [Cr(VI)] concentration in the fume and on ozone concentrations near the arc. Normally a single shield gas is used. This paper describes a double shroud torch that allows used of concentric shield gases of different compositions. A solid stainless steel wire was used for welding. The double shroud torch used secondary shield gases containing small amounts of the reducing agents NO and C2H4. The Cr(VI) concentration in the fume and ozone concentration at a fixed point relative to the arc were measured and compared with results when using a single shield gas. Use of the reducing agents in secondary shielding using the double shroud torch was found to offer advantages for ozone concentration reduction compared with use in a conventional torch, but this was not found to be an advantage for reducing Cr(VI) concentrations.

  15. Basic Oxygen Furnace steel slag aggregates for phosphorus treatment. Evaluation of its potential use as a substrate in constructed wetlands.

    PubMed

    Blanco, Ivan; Molle, Pascal; Sáenz de Miera, Luis E; Ansola, Gemma

    2016-02-01

    Basic Oxygen Furnace (BOF) steel slag aggregates from NW Spain were tested in batch and column experiments to evaluate its potential use as a substrate in constructed wetlands (CWs). The objectives of this study were to identify the main P removal mechanisms of BOF steel slag and determine its P removal capacity. Also, the results were used to discuss the suitability of this material as a substrate to be used in CWs. Batch experiments with BOF slag aggregates and increasing initial phosphate concentrations showed phosphate removal efficiencies between 84 and 99% and phosphate removal capacities from 0.12 to 8.78 mg P/g slag. A continuous flow column experiment filled with BOF slag aggregates receiving an influent synthetic solution of 15 mg P/L during 213 days showed a removal efficiency greater than 99% and a phosphate removal capacity of 3.1 mg P/g slag. In both experiments the main P removal mechanism was found to be calcium phosphate precipitation which depends on Ca(2+) and OH(-) release from the BOF steel slag after dissolution of Ca(OH)2 in water. P saturation of slag was reached within the upper sections of the column which showed phosphate removal capacities between 1.7 and 2.5 mg P/g slag. Once Ca(OH)2 was completely dissolved in these column sections, removal efficiencies declined gradually from 99% until reaching stable outlet concentrations with P removal efficiencies around 7% which depended on influent Ca(2+) for limited continuous calcium phosphate precipitation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Respiratory status of stainless steel and mild steel welders.

    PubMed

    Kalliomäki, P L; Kalliomäki, K; Korhonen, O; Nordman, H; Rahkonen, E; Vaaranen, V

    1982-01-01

    Eighty-three full-time stainless steel and 29 mild steel welders from one shipyard were examined clinically, and their lung function was measured. The stainless steel welders had used both tungsten inert-gas (low-fume concentration) and manual metal-arc (MMA) (high-fume concentration) welding methods. The individual exposure of the welders was estimated based on the time spent doing MMA welding, the amount of retained contaminants in the lungs (magnetopulmography), and urinary chromium excretion. The results suggest that there is a greater prevalence of small airway disease among shipyard mild steel MMA welders than among stainless steel welders. Among the stainless steel welders the impairment of lung function parameters was associated with the MMA welding method. The type of welding, then, is important when the health hazards of welders are studied, and welders cannot be regarded as a single, homogeneous group.

  17. Effectiveness of recycling light in ultra-bright short-arc discharge lamps.

    PubMed

    Malul, Asher; Nakar, Doron; Feuermann, Daniel; Gordon, Jeffrey M

    2007-10-17

    Recycling light back into a plasma lamp's radiant zone can enhance its radiance. Measurements are reported for the effectiveness, spectral properties and modified plasma radiance maps that result from light recycling with a specular hemispherical mirror in commercial 150 W ultrabright Xenon short-arc discharge lamps, motivated by projection, biomedical and high-temperature furnace applications. For certain spectral windows and plasma arc regions, radiance can be heightened by up to 70%. However, the overall light recycling efficiency is reduced to about half this value due to lamp geometry. The manner in which light-plasma interactions affect light recycling efficacy is also elucidated.

  18. Effect of Coating Thickness on the Properties of TiN Coatings Deposited on Tool Steels Using Cathodic Arc Pvd Technique

    NASA Astrophysics Data System (ADS)

    Mubarak, A.; Akhter, Parvez; Hamzah, Esah; Mohd Toff, Mohd Radzi Hj.; Qazi, Ishtiaq A.

    Titanium nitride (TiN) widely used as hard coating material, was coated on tool steels, namely on high-speed steel (HSS) and D2 tool steel by physical vapor deposition method. The study concentrated on cathodic arc physical vapor deposition (CAPVD), a technique used for the deposition of hard coatings for tooling applications, and which has many advantages. The main drawback of this technique, however, is the formation of macrodroplets (MDs) during deposition, resulting in films with rougher morphology. Various standard characterization techniques and equipment, such as electron microscopy, atomic force microscopy, hardness testing machine, scratch tester, and pin-on-disc machine, were used to analyze and quantify the following properties and parameters: surface morphology, thickness, hardness, adhesion, and coefficient of friction (COF) of the deposited coatings. Surface morphology revealed that the MDs produced during the etching stage, protruded through the TiN film, resulting in film with deteriorated surface features. Both coating thickness and indentation loads influenced the hardness of the deposited coatings. The coatings deposited on HSS exhibit better adhesion compared to those on D2 tool steel. Standard deviation indicates that the coating deposited with thickness around 6.7 μm showed the most stable trend of COF versus sliding distance.

  19. Microstructural Study of 17-4PH Stainless Steel after Plasma-Transferred Arc Welding.

    PubMed

    Deng, Dewei; Chen, Rui; Sun, Qi; Li, Xiaona

    2015-01-29

    The improvement of the surface qualities and surface hardening of precipitation hardened martensitic stainless steel 17-4PH was achieved by the plasma-transferred arc welding (PTAW) process deposited with Co-based alloy. The microstructure of the heat affected zone (HAZ) and base metal were characterized by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that there are obvious microstructural differences between the base metal and HAZ. For example, base material is transformed from lath martensite to austenite due to the heateffect of the welding process. On the other hand, the precipitate in the matrix (bar-like shape Cr₇C₃ phase with a width of about one hundred nanometres and a length of hundreds of nanometres) grows to a rectangular appearance with a width of about two hundred nanometres and a length of about one micron. Stacking fault could also be observed in the Cr₇C₃ after PTAW. The above means that welding can obviously improve the surface qualities.

  20. Initial Testing for the Recommendation of Improved Gas Metal Arc Welding Procedures for HY-80 Steel Plate Butt Joints at Norfolk Naval Shipyard

    DTIC Science & Technology

    2015-12-01

    is unlimited 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) Hull cut welding proficiency is an essential skill maintained by personnel...at naval shipyards. This thesis explores arc weld theory to develop ideal submarine hull butt joint designs and recommends preliminary testing to...shipboard hull welding applications, theoretically. Butt joint samples were created using HY-80 steel plate so that the following comparisons could

  1. Emissions of chromium (VI) from arc welding.

    PubMed

    Heung, William; Yun, Myoung-Jin; Chang, Daniel P Y; Green, Peter G; Halm, Chris

    2007-02-01

    The presence of Cr in the +6 oxidation state (Cr[VI]) is still observed in ambient air samples in California despite steps taken to reduce emissions from plating operations. One known source of emission of Cr(VI) is welding, especially with high Cr-content materials, such as stainless steels. An experimental effort was undertaken to expand and update Cr(VI) emission factors by conducting tests on four types of arc-welding operations: gas-metal arc welding (GMAW), shielded metal arc welding (SMAW), fluxcore arc welding, and pulsed GMAW. Standard American Welding Society hood results were compared with a total enclosure method that permitted isokinetic sampling for particle size-cut measurement, as well as total collection of the aerosol. The fraction of Cr(VI) emitted per unit mass of Cr electrode consumed was determined. Consistent with AP-42 data, initial results indicate that a significant fraction of the total Cr in the aerosol is in the +6 oxidation state. The fraction of Cr(VI) and total aerosol mass produced by the different arc welding methods varies with the type of welding process used. Self-shielded electrodes that do not use a shield gas, for example, SMAW, produce greater amounts of Cr(VI) per unit mass of electrode consumed. The formation of Cr(VI) from standard electrode wires used for welding mild steel was below the method detection limit after eliminating an artifact in the analytical method used.

  2. 49 CFR 178.45 - Specification 3T seamless steel cylinder.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., or electric furnace process steel of uniform quality is authorized. The steel analysis must conform... inches in diameter. (4) All openings must be circular. (5) All openings must be threaded. Threads must be in compliance with the following: (i) Each thread must be clean cut, even, without any checks, and to...

  3. 49 CFR 178.45 - Specification 3T seamless steel cylinder.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., or electric furnace process steel of uniform quality is authorized. The steel analysis must conform... inches in diameter. (4) All openings must be circular. (5) All openings must be threaded. Threads must be in compliance with the following: (i) Each thread must be clean cut, even, without any checks, and to...

  4. 49 CFR 178.45 - Specification 3T seamless steel cylinder.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., or electric furnace process steel of uniform quality is authorized. The steel analysis must conform... inches in diameter. (4) All openings must be circular. (5) All openings must be threaded. Threads must be in compliance with the following: (i) Each thread must be clean cut, even, without any checks, and to...

  5. Removal of hexavalent chromium in carbonic acid solution by oxidizing slag discharged from steelmaking process in electric arc furnace

    NASA Astrophysics Data System (ADS)

    Yokoyama, Seiji; Okazaki, Kohei; Sasano, Junji; Izaki, Masanobu

    2014-02-01

    Hexavalent chromium (Cr(VI)) is well-known to be a strong oxidizer, and is recognized as a carcinogen. Therefore, it is regulated for drinking water, soil, groundwater and sea by the environmental quality standards all over the world. In this study, it was attempted to remove Cr(VI) ion in a carbonic acid solution by the oxidizing slag that was discharged from the normal steelmaking process in an electric arc furnace. After the addition of the slag into the aqueous solution contained Cr(VI) ion, concentrations of Cr(VI) ion and total chromium (Cr(VI) + trivalent chromium (Cr(III)) ions decreased to lower detection limit of them. Therefore, the used slag could reduce Cr(VI) and fix Cr(III) ion on the slag. While Cr(VI) ion existed in the solution, iron did not dissolve from the slag. From the relation between predicted dissolution amount of iron(II) ion and amount of decrease in Cr(VI) ion, the Cr(VI) ion did not react with iron(II) ion dissolved from the slag. Therefore, Cr(VI) ion was removed by the reductive reaction between Cr(VI) ion and the iron(II) oxide (FeO) in the slag. This reaction progressed on the newly appeared surface of iron(II) oxide due to the dissolution of phase composed of calcium etc., which existed around iron(II) oxide grain in the slag.

  6. Great Lakes Steel -- PCI facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eichinger, F.T.; Dake, S.H.; Wagner, E.D.

    1997-12-31

    This paper discusses the planning, design, and start-up of the 90 tph PCI facility for National Steel`s Great Lakes Steel Division in River Rouge, MI. This project is owned and operated by Edison Energy Services, and was implemented on a fast-track basis by Raytheon Engineers and Constructors, Babcock Material Handling, and Babcock and Wilcox. This paper presents important process issues, basic design criteria, an the challenges of engineering and building a state-of-the-art PCI facility in two existing plants. Pulverized coal is prepared at the River Rouge Power Plant of Detroit Edison, is pneumatically conveyed 6,000 feet to a storage silomore » at Great Lakes Steel, and is injected into three blast furnaces.« less

  7. Heat treatment furnace

    DOEpatents

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

    2014-10-21

    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  8. High Temperature Transparent Furnace Development

    NASA Technical Reports Server (NTRS)

    Bates, Stephen C.

    1997-01-01

    This report describes the use of novel techniques for heat containment that could be used to build a high temperature transparent furnace. The primary objective of the work was to experimentally demonstrate transparent furnace operation at 1200 C. Secondary objectives were to understand furnace operation and furnace component specification to enable the design and construction of a low power prototype furnace for delivery to NASA in a follow-up project. The basic approach of the research was to couple high temperature component design with simple concept demonstration experiments that modify a commercially available transparent furnace rated at lower temperature. A detailed energy balance of the operating transparent furnace was performed, calculating heat losses through the furnace components as a result of conduction, radiation, and convection. The transparent furnace shells and furnace components were redesigned to permit furnace operation at at least 1200 C. Techniques were developed that are expected to lead to significantly improved heat containment compared with current transparent furnaces. The design of a thermal profile in a multizone high temperature transparent furnace design was also addressed. Experiments were performed to verify the energy balance analysis, to demonstrate some of the major furnace improvement techniques developed, and to demonstrate the overall feasibility of a high temperature transparent furnace. The important objective of the research was achieved: to demonstrate the feasibility of operating a transparent furnace at 1200 C.

  9. Investigation about the Chrome Steel Wire Arc Spray Process and the Resulting Coating Properties

    NASA Astrophysics Data System (ADS)

    Wilden, J.; Bergmann, J. P.; Jahn, S.; Knapp, S.; van Rodijnen, F.; Fischer, G.

    2007-12-01

    Nowadays, wire-arc spraying of chromium steel has gained an important market share for corrosion and wear protection applications. However, detailed studies are the basis for further process optimization. In order to optimize the process parameters and to evaluate the effects of the spray parameters DoE-based experiments had been carried out with high-speed camera shoots. In this article, the effects of spray current, voltage, and atomizing gas pressure on the particle jet properties, mean particle velocity and mean particle temperature and plume width on X46Cr13 wire are presented using an online process monitoring device. Moreover, the properties of the coatings concerning the morphology, composition and phase formation were subject of the investigations using SEM, EDX, and XRD-analysis. These deep investigations allow a defined verification of the influence of process parameters on spray plume and coating properties and are the basis for further process optimization.

  10. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME II. SINTERING, MANUAL OF PRACTICE

    EPA Science Inventory

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  11. High productivity injection practices at Rouge Steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barker, D.H.; Hegler, G.L.; Falls, C.E.

    1995-12-01

    Rouge Steel Company, located in Dearborn, Michigan, operates two blast furnaces. The smaller of the pair, ``B`` Furnace, has a hearth diameter of 20 feet and 12 tuyeres. It has averaged 2,290 NTHM (net ton of hot metal) per day of 8.2 NTHM per 100 cubic feet of working volume. ``C`` Furnace has a hearth diameter of 29 feet and 20 tuyeres. Both of these furnaces are single tap hole furnaces. Prior to its reline in 1991, ``C`` Furnace was producing at a rate of 3,300 NTHM/day or about 6.25 NTHM/100 cfwv. In November, 1994 it averaged 5,106 NTHM/day ormore » 9.6 NTHM/100 cfwv. This paper discusses how the current production rates were achieved. Also, the areas that needed to be addressed as production increased will be described. These areas include casthouse arrangement and workload, hot metal ladle capacity, slag pot capacity and charging capability. Coupled with the high blast temperature capability, the furnace was provided with a new natural gas injection system that injected the gas through the blowpipes and a natural gas injection system to enrich the stove gas. Following the furnace reline, natural gas has been used in three ways: tuyere level control; combination injection; and stove gas enrichment. Coke consumption rate has also decreased per NTHM.« less

  12. Thermal Behavior of an HSLA Steel and the Impact in Phase Transformation: Submerged Arc Welding (SAW) Process Approach to Pipelines

    NASA Astrophysics Data System (ADS)

    Costa, P. S.; Reyes-Valdés, F. A.; Saldaña-Garcés, R.; Delgado, E. R.; Salinas-Rodríguez, A.

    Heat input during welding metal fusion generates different transformations, such as grain growth, hydrogen cracking, and the formation of brittle structures, generally associated with the heat-affected zone (HAZ). For this reason, it is very important to know the behavior of this area before welding. This paper presents a study of the thermal behavior and its effect on phase transformations in the HAZ, depending on cooling rates (0.1-200 °C/s) to obtain continuous cooling transformation (CCT) curves for an high-strength low-alloy (HSLA) steel. In order to determine the formed phases, optical microscopy and Vickers microhardness measurement were used. The experimental CCT curve was obtained from an HSLA steel, and the results showed that, with the used cooling conditions, the steel did not provide formation of brittle structures. Therefore, it is unlikely that welds made by submerged arc welding (SAW) may lead to hydrogen embrittlement in the HAZ, which is one of the biggest problems of cracking in gas conduction pipelines. In addition, with these results, it will be possible to control the microstructure to optimize the pipe fabrication with SAW process in industrial plants.

  13. Efficient 'Optical Furnace': A Cheaper Way to Make Solar Cells is Reaching the Marketplace

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    von Kuegelgen, T.

    In Bhushan Sopori's laboratory, you'll find a series of optical furnaces he has developed for fabricating solar cells. When not in use, they sit there discreetly among the lab equipment. But when a solar silicon wafer is placed inside one for processing, Sopori walks over to a computer and types in a temperature profile. Almost immediately this fires up the furnace, which glows inside and selectively heats up the silicon wafer to 800 degrees centigrade by the intense light it produces. Sopori, a principal engineer at the National Renewable Energy Laboratory, has been researching and developing optical furnace technology formore » around 20 years. He says it's a challenging technology to develop because there are many issues to consider when you process a solar cell, especially in optics. Despite the challenges, Sopori and his research team have advanced the technology to the point where it will benefit all solar cell manufacturers. They are now developing a commercial version of the furnace in partnership with a manufacturer. 'This advanced optical furnace is highly energy efficient, and it can be used to manufacture any type of solar cell,' he says. Each type of solar cell or manufacturing process typically requires a different furnace configuration and temperature profile. With NREL's new optical furnace system, a solar cell manufacturer can ask the computer for any temperature profile needed for processing a solar cell, and the same type of furnace is suitable for several solar cell fabrication process steps. 'In the future, solar cell manufacturers will only need this one optical furnace because it can be used for any process, including diffusion, metallization and oxidation,' Sopori says. 'This helps reduce manufacturing costs.' One startup company, Applied Optical Systems, has recognized the furnace's potential for manufacturing thin-film silicon cells. 'We'd like to develop thin-film silicon cells with higher efficiencies, up to 15 to 18 percent, and we

  14. Human biomonitoring of chromium and nickel from an experimental exposure to manual metal arc welding fumes of low and high alloyed steel.

    PubMed

    Bertram, Jens; Brand, Peter; Schettgen, Thomas; Lenz, Klaus; Purrio, Ellwyn; Reisgen, Uwe; Kraus, Thomas

    2015-05-01

    The uptake and elimination of metals from welding fumes is currently not fully understood. In the Aachen Workplace Simulation Laboratory (AWSL) it is possible to investigate the impact of welding fumes on human subjects under controlled exposure conditions. In this study, the uptake and elimination of chromium or chromium (VI) respectively as well as nickel was studied in subjects after exposure to the emissions of a manual metal arc welding process using low or high alloyed steel. In this present study 12 healthy male non-smokers, who never worked as welders before, were exposed for 6h to welding fumes of a manual metal arc welding process. In a three-fold crossover study design, subjects were exposed in randomized order to either clean air, emissions from welding low alloyed steel, and emissions from welding high alloyed steel. Particle mass concentration of the exposure aerosol was 2.5mg m(-3). The content of chromium and nickel in the air was determined by analysing air filter samples on a high emission scenario. Urine analysis for chromium and nickel was performed before and after exposure using methods of human biomonitoring. There were significantly elevated chromium levels after exposure to welding fumes from high alloyed steel compared to urinary chromium levels before exposure to high alloyed welding fumes, as well as compared to the other exposure scenarios. The mean values increased from 0.27 µg l(-1) to 18.62 µg l(-1). The results were in good agreement with already existing correlations between external and internal exposure (German exposure equivalent for carcinogenic working materials EKA). The variability of urinary chromium levels was high. For urinary nickel no significant changes could be detected at all. Six-hour exposure to 2.5mg m(-3) high alloyed manual metal arc welding fumes lead to elevated urinary chromium levels far higher (7.11-34.16 µg l(-1)) than the German biological exposure reference value (BAR) of 0.6 µg l(-1) directly after

  15. Gas Furnace with Pulsed Feeding of the Heating Agent for Volume Precision Heat Treatment of CCM Rolls

    NASA Astrophysics Data System (ADS)

    Moroz, V. I.; Egorova, V. M.; Gusev, S. V.

    2001-05-01

    A standard chamber batch furnace of the Severstal' plant has been modified for precision heat treatment of CCM rolls. The certification tests of a charge of rolls from steel 24KhM1F have shown the technical and economical advantages of the new design.

  16. Thermal Arc Spray Overview

    NASA Astrophysics Data System (ADS)

    Hafiz Abd Malek, Muhamad; Hayati Saad, Nor; Kiyai Abas, Sunhaji; Mohd Shah, Noriyati

    2013-06-01

    Usage of protective coating for corrosion protection was on highly demand during the past decade; and thermal spray coating played a major part during that time. In recent years, the thermal arc spray coating becomes a popular coating. Many big players in oil and gas such as PETRONAS, EXXON MOBIL and SHELL in Malaysia tend to use the coating on steel structure as a corrosion protection. Further developments in coating processes, the devices, and raw materials have led to expansion of functional coatings and applications scope from conventional coating to specialized industries. It is widely used because of its ability to withstand high process temperature, offer advantages in efficiency, lower cost and acts as a corrosion protection. Previous research also indicated that the thermal arc spray offers better coating properties compared to other methods of spray. This paper reviews some critical area of thermal spray coating by discussing the process/parameter of thermal arc spray technology and quality control of coating. Coating performance against corrosion, wear and special characteristic of coating are also described. The field application of arc spray technology are demonstrated and reviewed.

  17. Microscopy of Alloy Formation on Arc Plasma Sintered Oxide Dispersion Strengthen (ODS) Steel

    NASA Astrophysics Data System (ADS)

    Bandriyana, B.; Sujatno, A.; Salam, R.; Dimyati, A.; Untoro, P.

    2017-07-01

    The oxide dispersed strengthened (ODS) alloys steel developed as structure material for nuclear power plants (NPP) has good resistant against creep due to their unique microstructure. Microscopy investigation on the microstructure formation during alloying process especially at the early stages was carried out to study the correlation between structure and property of ODS alloys. This was possible thanks to the arc plasma sintering (APS) device which can simulate the time dependent alloying processes. The ODS sample with composition of 88 wt.% Fe and 12 wt.% Cr powder dispersed with 1 wt.% ZrO2 nano powder was mixed in a high energy milling, isostatic compressed to form sample coins and then alloyed in APS. The Scanning Electron Microscope (SEM) with X-ray Diffraction Spectroscopy (EDX) line scan and mapping was used to characterize the microstructure and elemental composition distribution of the samples. The alloying process with unification of each Fe and Cr phase continued by the alloying formation of Fe-Cr by inter-diffusion of both Fe and Cr and followed by the improvement of the mechanical properties of hardness.

  18. Microstructural Study of 17-4PH Stainless Steel after Plasma-Transferred Arc Welding

    PubMed Central

    Deng, Dewei; Chen, Rui; Sun, Qi; Li, Xiaona

    2015-01-01

    The improvement of the surface qualities and surface hardening of precipitation hardened martensitic stainless steel 17-4PH was achieved by the plasma-transferred arc welding (PTAW) process deposited with Co-based alloy. The microstructure of the heat affected zone (HAZ) and base metal were characterized by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that there are obvious microstructural differences between the base metal and HAZ. For example, base material is transformed from lath martensite to austenite due to the heateffect of the welding process. On the other hand, the precipitate in the matrix (bar-like shape Cr7C3 phase with a width of about one hundred nanometres and a length of hundreds of nanometres) grows to a rectangular appearance with a width of about two hundred nanometres and a length of about one micron. Stacking fault could also be observed in the Cr7C3 after PTAW. The above means that welding can obviously improve the surface qualities. PMID:28787947

  19. Banking the Furnace: Restructuring of the Steel Industry in Eight Countries.

    ERIC Educational Resources Information Center

    Bain, Trevor

    A study examined how the cross-national differences in the social contract among managers, unions, and government influenced adjustment strategies in steel. The restructuring process in eight major steel-producing countries was studied to determine who bore the costs of restructuring--employers, employees, or government--and which industrial…

  20. Influence of Short Austenitization Treatments on the Mechanical Properties of Low-Alloy Steels for Hot Forming Applications

    NASA Astrophysics Data System (ADS)

    Holzweissig, Martin Joachim; Lackmann, Jan; Konrad, Stefan; Schaper, Mirko; Niendorf, Thomas

    2015-07-01

    The current work elucidates an improvement of the mechanical properties of tool-quenched low-alloy steel by employing extremely short austenitization durations utilizing a press heating arrangement. Specifically, the influence of different austenitization treatments—involving austenitization durations ranging from three to 15 seconds—on the mechanical properties of low-alloy steel in comparison to an industrial standard furnace process was examined. A thorough set of experiments was conducted to investigate the role of different austenitization durations and temperatures on the resulting mechanical properties such as hardness, bending angle, tensile strength, and strain at fracture. The most important finding is that the hardness, the bending angle as well as the tensile strength increase with shortened austenitization durations. Furthermore, the ductility of the steels exhibits almost no difference following the short austenitization durations and the standard furnace process. The enhancement of the mechanical properties imposed by the short heat treatments investigated, is related to a refinement of microstructural features as compared to the standard furnace process.

  1. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel: A Computational Investigation

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Snipes, J. S.; Galgalikar, R.; Ramaswami, S.; Yavari, R.; Yen, C.-F.; Cheeseman, B. A.

    2014-09-01

    In our recent work, a multi-physics computational model for the conventional gas metal arc welding (GMAW) joining process was introduced. The model is of a modular type and comprises five modules, each designed to handle a specific aspect of the GMAW process, i.e.: (i) electro-dynamics of the welding-gun; (ii) radiation-/convection-controlled heat transfer from the electric-arc to the workpiece and mass transfer from the filler-metal consumable electrode to the weld; (iii) prediction of the temporal evolution and the spatial distribution of thermal and mechanical fields within the weld region during the GMAW joining process; (iv) the resulting temporal evolution and spatial distribution of the material microstructure throughout the weld region; and (v) spatial distribution of the as-welded material mechanical properties. In the present work, the GMAW process model has been upgraded with respect to its predictive capabilities regarding the spatial distribution of the mechanical properties controlling the ballistic-limit (i.e., penetration-resistance) of the weld. The model is upgraded through the introduction of the sixth module in the present work in recognition of the fact that in thick steel GMAW weldments, the overall ballistic performance of the armor may become controlled by the (often inferior) ballistic limits of its weld (fusion and heat-affected) zones. To demonstrate the utility of the upgraded GMAW process model, it is next applied to the case of butt-welding of a prototypical high-hardness armor-grade martensitic steel, MIL A46100. The model predictions concerning the spatial distribution of the material microstructure and ballistic-limit-controlling mechanical properties within the MIL A46100 butt-weld are found to be consistent with prior observations and general expectations.

  2. POLLUTION EFFECTS OF ABNORMAL OPERATIONS IN IRON AND STEEL MAKING. VOLUME VI. BASIC OXYGEN PROCESS, MANUAL OF PRACTICE

    EPA Science Inventory

    The report is one in a six-volume series considering abnormal operating conditions (AOCs) in the primary section (sintering, blast furnace ironmaking, open hearth, electric furnace, and basic oxygen steelmaking) of an integrated iron and steel plant. Pollution standards, generall...

  3. 49 CFR 192.113 - Longitudinal joint factor (E) for steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Longitudinal joint factor (E) for steel pipe. 192... § 192.113 Longitudinal joint factor (E) for steel pipe. The longitudinal joint factor to be used in the... class Longitudinal joint factor (E) ASTM A 53/A53M Seamless 1.00 Electric resistance welded 1.00 Furnace...

  4. 49 CFR 192.113 - Longitudinal joint factor (E) for steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Longitudinal joint factor (E) for steel pipe. 192... § 192.113 Longitudinal joint factor (E) for steel pipe. The longitudinal joint factor to be used in the... class Longitudinal joint factor (E) ASTM A 53/A53M Seamless 1.00 Electric resistance welded 1.00 Furnace...

  5. 49 CFR 192.113 - Longitudinal joint factor (E) for steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Longitudinal joint factor (E) for steel pipe. 192... § 192.113 Longitudinal joint factor (E) for steel pipe. The longitudinal joint factor to be used in the... class Longitudinal joint factor (E) ASTM A 53/A53M Seamless 1.00 Electric resistance welded 1.00 Furnace...

  6. 49 CFR 192.113 - Longitudinal joint factor (E) for steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Longitudinal joint factor (E) for steel pipe. 192... § 192.113 Longitudinal joint factor (E) for steel pipe. The longitudinal joint factor to be used in the... class Longitudinal joint factor (E) ASTM A 53/A53M Seamless 1.00 Electric resistance welded 1.00 Furnace...

  7. Reuse of steel slag in bituminous paving mixtures.

    PubMed

    Sorlini, Sabrina; Sanzeni, Alex; Rondi, Luca

    2012-03-30

    This paper presents a comprehensive study to evaluate the mechanical properties and environmental suitability of electric arc furnace (EAF) steel slag in bituminous paving mixtures. A variety of tests were executed on samples of EAF slag to characterize the physical, geometrical, mechanical and chemical properties as required by UNI EN specifications, focusing additionally on the volumetric expansion associated with hydration of free CaO and MgO. Five bituminous mixtures of aggregates for flexible road pavement were designed containing up to 40% of EAF slag and were tested to determine Marshall stability and indirect tensile strength. The leaching behaviour of slag samples and bituminous mixtures was evaluated according to the UNI EN leaching test. The tested slag showed satisfactory physical and mechanical properties and a release of pollutants generally below the limits set by the Italian code. Tests on volume stability of fresh materials confirmed that a period of 2-3 months is necessary to reduce effects of oxides hydration. The results of tests performed on bituminous mixtures with EAF slag were comparable with the performance of mixtures containing natural aggregates and the leaching tests provided satisfactory results. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Surface Modification of Micro-Alloyed High-Strength Low-Alloy Steel by Controlled TIG Arcing Process

    NASA Astrophysics Data System (ADS)

    Ghosh, P. K.; Kumar, Ravindra

    2015-02-01

    Surface modification of micro-alloyed HSLA steel plate has been carried out by autogenous conventional and pulse current tungsten inert gas arcing (TIGA) processes at different welding parameters while the energy input was kept constant. At a given energy input the influence of pulse parameters on the characteristics of surface modification has been studied in case of employing single and multi-run procedure. The role of pulse parameters has been studied by considering their summarized influence defined by a factor Φ. The variation in Φ and pulse frequency has been found to significantly affect the thermal behavior of fusion and accordingly the width and penetration of the modified region along with its microstructure, hardness and wear characteristics. It is found that pulsed TIGA is relatively more advantageous over the conventional TIGA process, as it leads to higher hardness, improved wear resistance, and a better control over surface characteristics.

  9. Effect of plasma arc welding variables on fusion zone grain size and hardness of AISI 321 austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Kondapalli, S. P.

    2017-12-01

    In the present work, pulsed current microplasma arc welding is carried out on AISI 321 austenitic stainless steel of 0.3 mm thickness. Peak current, Base current, Pulse rate and Pulse width are chosen as the input variables, whereas grain size and hardness are considered as output responses. Response surface method is adopted by using Box-Behnken Design, and in total 27 experiments are performed. Empirical relation between input and output response is developed using statistical software and analysis of variance (ANOVA) at 95% confidence level to check the adequacy. The main effect and interaction effect of input variables on output response are also studied.

  10. Looking Northwest at Furnace Control Panels and Gas Control Furnace ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Northwest at Furnace Control Panels and Gas Control Furnace in Red Room Within Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

  11. Thin-film versus slurry-phase carbonation of steel slag: CO₂ uptake and effects on mineralogy.

    PubMed

    Baciocchi, R; Costa, G; Di Gianfilippo, M; Polettini, A; Pomi, R; Stramazzo, A

    2015-01-01

    The results of direct aqueous accelerated carbonation of three types of steel manufacturing residues, including an electric arc furnace (EAF) slag and two basic oxygen furnace (BOF) slags, are reported. Batch accelerated carbonation tests were conducted at different temperatures and CO2 pressures applying the thin-film route (liquid to solid, L/S, ratio=0.3L/kg) or the slurry-phase route (L/S ratio=5L/kg). The CO2 uptake strongly depended on both the slag characteristics and the process route; maximum yields of 280 (EAF), 325 (BOF1) and 403 (BOF2) gCO2/kg slag were achieved in slurry phase at T=100°C and pCO2=10 bar. Differently from previous studies, additional carbonates (other than Ca-based phases) were retrieved in the carbonated BOF slags, indicating that also Mg-, Fe- and Mn-containing phases partially reacted with CO2 under the tested conditions. The results hence show that the effects of accelerated carbonation in terms of CO2 uptake capacity, yield of mineral conversion into carbonates and mineralogy of the treated product, strongly rely on several factors. These include, above all, the mineralogy of the original material and the operating conditions adopted, which thus need specific case-by-case optimization to maximize the CO2 sequestration yield. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Trace metals related to historical iron smelting at Hopewell Furnace National Historic Site, Berks and Chester Counties, Pennsylvania

    USGS Publications Warehouse

    Sloto, Ronald A.

    2011-01-01

    Iron ore containing elevated concentrations of trace metals was smelted at Hopewell Furnace during its 113 years of operation (1771-1883). The ore used at Hopewell Furnace was obtained from iron mines within 5 miles of the furnace. The iron-ore deposits were formed about 200 million years ago and contain abundant magnetite, the primary iron mineral, and accessory minerals enriched in arsenic, cobalt, copper, lead, and other metals. Hopewell Furnace, built by Mark Bird during 1770-71, was one of the last of the charcoal-burning, cold-blast iron furnaces operated in Pennsylvania. The most productive years for Hopewell Furnace were from 1830 to 1837. Castings were the most profitable product, especially the popular Hopewell Stove. More than 80,000 stoves were cast at Hopewell, which produced as many as 23 types and sizes of cooking and heating stoves. Beginning in the 1840s, the iron industry shifted to large-scale, steam-driven coke and anthracite furnaces. Independent rural enterprises like Hopewell could no longer compete when the iron and steel industries consolidated in urban manufacturing centers. The furnace ceased operation in 1883 (Kurjack, 1954). The U.S. Geological Survey (USGS), in cooperation with the National Park Service, completed a study at Hopewell Furnace National Historic Site (NHS) in Berks and Chester Counties, Pennsylvania, to determine the fate of toxic trace metals, such as arsenic, cobalt, and lead, released into the environment during historical iron-smelting operations. The results of the study, conducted during 2008-10, are presented in this fact sheet.

  13. Carbon-free induction furnace

    DOEpatents

    Holcombe, Cressie E.; Masters, David R.; Pfeiler, William A.

    1985-01-01

    An induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of carbon free materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloy. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an RF induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650.degree. C. for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

  14. [Dust and silica exposure on metallurgical furnace maintenance using refractory materials].

    PubMed

    Garattini, S; Barbieri, P G; Bottone, F; Brunelli, E; Carminati, F; Chiari, R; Sarnico, M

    2012-01-01

    In the metallurgical industries the silica risk has long been known, particularly for the refractoryes maintenance workers. The maintenance of furnaces, ladles and tundisches refractory linings, on the current organization of production, is provided by companies under contract. The information available about the characterization of risk for this group of workers are at present inadequate. The study investigates the exposure to dust, also containing free crystalline silica (SLC), through the analysis of samples of commercial products used in the reconstruction of refractory linings of furnaces, ladles and tundisches, materials from the demolition of refractory articles and dust from work areas. It also presents the results of an environmental investigation conducted during the demolition and reconstruction of the refractory in three steel mills. The Authors, by the numerous inspections and the systematic survey of working conditions, have formulated a SLC risk profile and some proposals for prevention.

  15. Corrosion behavior of sensitized duplex stainless steel.

    PubMed

    Torres, F J; Panyayong, W; Rogers, W; Velasquez-Plata, D; Oshida, Y; Moore, B K

    1998-01-01

    The present work investigates the corrosion behavior of 2205 duplex stainless steel in 0.9% NaCl solution after various heat-treatments, and compares it to that of 316L austenitic stainless steel. Both stainless steels were heat-treated at 500, 650, and 800 degrees C in air for 1 h, followed by furnace cooling. Each heat-treated sample was examined for their microstructures and Vickers micro-hardness, and subjected to the X-ray diffraction for the phase identification. Using potentiostatic polarization method, each heat-treated sample was corrosion-tested in 37 degrees C 0.9% NaCl solution to estimate its corrosion rate. It was found that simulated sensitization showed an adverse influence on both steels, indicating that corrosion rates increased by increasing the sensitization temperatures.

  16. Recovery Act: Waste Energy Project at AK Steel Corporation Middletown

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Joyce, Jeffrey

    2012-06-30

    In 2008, Air Products and Chemicals, Inc. (“Air Products”) began development of a project to beneficially utilize waste blast furnace “topgas” generated in the course of the iron-making process at AK Steel Corporation’s Middletown, Ohio works. In early 2010, Air Products was awarded DOE Assistance Agreement DE-EE002736 to further develop and build the combined-cycle power generation facility. In June 2012, Air Products and AK Steel Corporation terminated work when it was determined that the project would not be economically viable at that time nor in the foreseeable future. The project would have achieved the FOA-0000044 Statement of Project Objectives bymore » demonstrating, at a commercial scale, the technology to capture, treat, and convert blast furnace topgas into electric power and thermal energy.« less

  17. Artificial intelligence-based computer modeling tools for controlling slag foaming in electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Wilson, Eric Lee

    Due to increased competition in a world economy, steel companies are currently interested in developing techniques that will allow for the improvement of the steelmaking process, either by increasing output efficiency or by improving the quality of their product, or both. Slag foaming is one practice that has been shown to contribute to both these goals. However, slag foaming is highly dynamic and difficult to model or control. This dissertation describes an effort to use artificial intelligence-based tools (genetic algorithms, fuzzy logic, and neural networks) to both model and control the slag foaming process. Specifically, a neural network is trained and tested on slag foaming data provided by a steel plant. This neural network model is then controlled by a fuzzy logic controller, which in turn is optimized by a genetic algorithm. This tuned controller is then installed at a steel plant and given control be a more efficient slag foaming controller than what was previously used by the steel plant.

  18. Non-carbon induction furnace

    DOEpatents

    Holcombe, C.E.; Masters, D.R.; Pfeiler, W.A.

    1984-01-06

    The present invention is directed to an induction furnace for melting and casting highly pure metals and alloys such as uranium and uranium alloys in such a manner as to minimize contamination of the melt by carbon derived from the materials and the environment within the furnace. The subject furnace is constructed of non-carbon materials and is housed within a conventional vacuum chamber. The furnace comprises a ceramic oxide crucible for holding the charge of metal or alloys. The heating of the crucible is achieved by a plasma-sprayed tungsten susceptor surrounding the crucible which, in turn, is heated by an rf induction coil separated from the susceptor by a cylinder of inorganic insulation. The furnace of the present invention is capable of being rapidly cycled from ambient temperatures to about 1650/sup 0/C for effectively melting uranium and uranium alloys without the attendant carbon contamination problems previously encountered when using carbon-bearing furnace materials.

  19. Effect of Microstructure on Stress Corrosion Cracking Behaviour of High Nitrogen Stainless Steel Gas Tungsten Arc Welds

    NASA Astrophysics Data System (ADS)

    Mohammed, Raffi; Srinivasa Rao, K.; Madhusudhan Reddy, G.

    2018-03-01

    Present work is aimed to improve stress corrosion cracking resistance of high nitrogen steel and its welds. An attempt to weld high nitrogen steel of 5 mm thick plate using gas tungsten arc welding (GTAW) with three high strength age hardenable fillers i.e., 11-10 PH filler, PH 13- 8Mo and maraging grade of MDN 250 filler is made. Welds were characterized by optical microscopy and scanning electron microscopy. Vickers hardness testing of the welds was carried out to study the mechanical behaviour of welds. Potentio-dynamic polarization studies were done to determine pitting corrosion resistance in aerated 3.5% NaCl solution. Stress corrosion cracking (SCC) testing was carried out using constant load type machine with applied stress of 50% yield strength and in 45% MgCl2 solution boiling at 155°C. The results of the present investigation established that improvement in resistance to stress corrosion cracking was observed for PH 13- 8Mo GTA welds when compared to 11-10 PH and MDN 250 GTA welds. However, All GTA welds failed in the weld interface region. This may be attributed to relatively lower pitting potential in weld interface which acts as active site and the initiation source of pitting.

  20. Fatigue crack growth behavior of pressure vessel steels and submerged arc weldments in a high-temperature pressurized water environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liaw, P.K.; Logsdon, W.A.; Begley, J.A.

    1989-10-01

    The fatigue crack growth rate (FCGR) properties of SA508 Cl 2a and SA533 Gr A Cl 2 pressure vessel steels and the corresponding automatic submerged arc weldments were developed in a high-temperature pressurized water (HPW) environment at 288{degrees} C (550{degrees} F) and 7.2 MPa (1044 psi) at load ratios of 0.20 and 0.50. The properties were generally conservative compared to American Society of Mechanical Engineers Section XI water environment reference curve. The growth rate of fatigue cracks in the base materials, however, was faster in the HPW environment than in a 288{degrees} C (550{degrees} F) base line air environment. Themore » growth rate of fatigue cracks in the two submerged arc weldments was also accelerated in the HPW environment but to a lesser degree than that demonstrated by the base materials. In the air environment, fatigue striations were observed, independent of material and load ratio, while in the HPW environment, some intergranular facets were present. The greater environmental effect on crack growth rates displayed by the base materials compared the weldments attributed to a different sulfide composition and morphology.« less

  1. Effects of Heating and Cooling Rates on Phase Transformations in 10 Wt Pct Ni Steel and Their Application to Gas Tungsten Arc Welding

    NASA Astrophysics Data System (ADS)

    Barrick, Erin J.; Jain, Divya; DuPont, John N.; Seidman, David N.

    2017-12-01

    10 wt pct Ni steel is a high-strength steel that possesses good ballistic resistance from the deformation induced transformation of austenite to martensite, known as the transformation-induced-plasticity effect. The effects of rapid heating and cooling rates associated with welding thermal cycles on the phase transformations and microstructures, specifically in the heat-affected zone, were determined using dilatometry, microhardness, and microstructural characterization. Heating rate experiments demonstrate that the Ac3 temperature is dependent on heating rate, varying from 1094 K (821 °C) at a heating rate of 1 °C/s to 1324 K (1051 °C) at a heating rate of 1830 °C/s. A continuous cooling transformation diagram produced for 10 wt pct Ni steel reveals that martensite will form over a wide range of cooling rates, which reflects a very high hardenability of this alloy. These results were applied to a single pass, autogenous, gas tungsten arc weld. The diffusion of nickel from regions of austenite to martensite during the welding thermal cycle manifests itself in a muddled, rod-like lath martensitic microstructure. The results of these studies show that the nickel enrichment of the austenite in 10 wt pct Ni steel plays a critical role in phase transformations during welding.

  2. The nitrogen effect on Type 304L austenitic stainless steel weld metal welded with a GTA (Gas Tungsten Arc) system under ambient and hyperbaric conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Okagawa, R.K.

    1984-01-01

    Small amounts of nitrogen were injected into Type 304L austenitic stainless steel weld metal. This was accomplished by using an Ar-N/sub 2/ shield gas mixture in combination with a controlled argon atmosphere on autogeneous Gas Tungsten Arc (GTA) welds. Weld metal nitrogen as a function of nitrogen shield gas content and applied pressure was examined. Nitrogen shield gas contents above 4% were found to have a major effect on the weld metal microstructure. The base metal nitrogen did not influence the nitrogen solubility reaction or solidification behavior during welding. For Type 304L austenitic stainless steel, a nitrogen coefficient of 13.4more » was determined for the nickel equivalent expression. 63 refs., 19 figs., 4 tabs.« less

  3. Environmental risk assessment of steel-making slags and the potential use of LD slag in mitigating methane emissions and the grain arsenic level in rice (Oryza sativa L.).

    PubMed

    Gwon, Hyo Suk; Khan, Muhammad Israr; Alam, Muhammad Ashraful; Das, Suvendu; Kim, Pil Joo

    2018-04-13

    Over the past decades, with increasing steel manufacturing, the huge amount of by-products (slags) generated need to be reused in an efficient way not only to reduce landfill slag sites but also for sustainable and eco-friendly agriculture. Our preliminary laboratory study revealed that compared to blast furnace slag, electric arc furnace slag and ladle furnace slag, the Linz-Donawitz converter (LD) slag markedly decreased CH 4 production rate and increased microbial activity. In the greenhouse experiment, the LD slag amendment (2.0 Mg ha -1 ) significantly (p < 0.05) increased grain yield by 10.3-15.2%, reduced CH 4 emissions by 17.8-24.0%, and decreased inorganic As concentrations in grain by 18.3-19.6%, compared to the unamended control. The increase in yield is attributed to the increased photosynthetic rates and increased availability of nutrients to the rice plant. Whereas, the decrease in CH 4 emissions could be due to the higher Fe availability in the slag amended soil, which acted as an alternate electron acceptor, thereby, suppressed CH 4 emissions. The more Fe-plaque formation which could adsorb more As and the competitive inhibition of As uptake with higher availability of Si could be the reason for the decrease in As uptake by rice cultivated with LD slag amendment. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Phase structures and morphologies of tempered CA6NM stainless steel welded by hybrid laser-arc process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mirakhorli, F., E-mail: Fatemeh.mirakhorli.1@ens.e

    The post-weld tempered microstructure of hybrid laser-arc welded CA6NM, a cast low carbon martensitic stainless steel, was investigated. The microstructural evolutions from the fusion zone to the base metal were characterized in detail using optical microscopy, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and microhardness techniques. The fusion zone, in its post-weld tempered condition, consisted of tempered lath martensite, residual delta-ferrite with various morphologies, reversed austenite and chromium carbides. The reversed austenite, which can be detected through both EBSD and XRD techniques, was found to be finely dispersed along the martensite lath boundaries, particularly at triplemore » junctions. Based on the EBSD analysis, the orientation relationship between the reversed austenite and the adjacent martensite laths seemed to follow the Kurdjumov-Sachs (K-S) model. The results also revealed the presence of the reversed austenite in the different regions of the heat affected zone after post-weld tempering. The microindentation hardness distribution was measured, and correlated to the evolution of the corresponding microstructure across the welds. - Highlights: •The EBSD analysis was performed on hybrid laser-arc welded CA6NM. •The FZ consisted of tempered lath martensite, reversed austenite, carbides and δ ferrite after tempering. •The reversed γ was formed along the α′ lath boundaries, particularly at triple junctions.« less

  5. Multiphysics Modeling and Simulations of Mil A46100 Armor-Grade Martensitic Steel Gas Metal Arc Welding Process

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Ramaswami, S.; Snipes, J. S.; Yen, C.-F.; Cheeseman, B. A.; Montgomery, J. S.

    2013-10-01

    A multiphysics computational model has been developed for the conventional Gas Metal Arc Welding (GMAW) joining process and used to analyze butt-welding of MIL A46100, a prototypical high-hardness armor martensitic steel. The model consists of five distinct modules, each covering a specific aspect of the GMAW process, i.e., (a) dynamics of welding-gun behavior; (b) heat transfer from the electric arc and mass transfer from the electrode to the weld; (c) development of thermal and mechanical fields during the GMAW process; (d) the associated evolution and spatial distribution of the material microstructure throughout the weld region; and (e) the final spatial distribution of the as-welded material properties. To make the newly developed GMAW process model applicable to MIL A46100, the basic physical-metallurgy concepts and principles for this material have to be investigated and properly accounted for/modeled. The newly developed GMAW process model enables establishment of the relationship between the GMAW process parameters (e.g., open circuit voltage, welding current, electrode diameter, electrode-tip/weld distance, filler-metal feed speed, and gun travel speed), workpiece material chemistry, and the spatial distribution of as-welded material microstructure and properties. The predictions of the present GMAW model pertaining to the spatial distribution of the material microstructure and properties within the MIL A46100 weld region are found to be consistent with general expectations and prior observations.

  6. Signal analysis of voltage noise in welding arcs. [gas tungsten arc welding

    NASA Technical Reports Server (NTRS)

    Elis, E.; Eagar, T. W.

    1982-01-01

    Gas tungsten arc welds were made on low alloy steel plates to which intentional defects (discontinuities) were imposed. Disruption of shielding gas, welding over surface films, and tack welds produce changes in what is otherwise a relatively uniform voltage signal. The arc voltage was 15 volts + or - 2 volts with 300 mV ripple noise from the power supply. Changes in this steady noise voltage varied from 50 mV to less than one millivolt depending on the severity and the type of change experienced. In some instances the changes were easily detected by analysis of the signal in real time, while in other cases the signal had to transformed to the frequency domain in order to detect the changes. Discontinuities as small as 1.5 mm in length were detected. The ultimate sensitivity and reproducibility of the technique is still being investigated.

  7. Study on the Removal of Gases in RH Refining Progress through Experiments Using Vacuum Induction Furnace

    NASA Astrophysics Data System (ADS)

    Niu, Deliang; Liu, Qingcai; Wang, Zhu; Ren, Shan; Lan, Yuanpei; Xu, Minren

    Removal of gas is the major function of RH degasser. To optimize the RH refining craft in Chongqing Iron and Steel Co. Ltd, the degassing effect of RH degasser at different degrees of vacuum was investigated using a vacuum induction furnace. In addition, the effect of processing time on the gas content dissolved in molten steel was also studied. The results showed that degree of vacuum was one of the important factors that determined the degassing efficiency in RH refining process. High vacuum degree is helpful in the removal of gas, especially in the removal of [H] dissolved in molten steel. The processing time could be reduced from 25-30 min to 15 minutes and gas content could also meet the demand of RH refining.

  8. FURNACE NO. 1, THE ORIGINAL FURNACE OF THE GLASS FACTORY; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FURNACE NO. 1, THE ORIGINAL FURNACE OF THE GLASS FACTORY; TO THE LEFT IS A GLORY HOLE, POSSIBLY DATING FROM THE NINETEENTH CENTURY; THE SQUARE-SHAPED GLORY HOLE TO THE RIGHT PROBABLY DATES FROM THE 1950S. - Westmoreland Glass Company, Seventh & Kier Streets, Grapeville, Westmoreland County, PA

  9. Evaluating optical hazards from plasma arc cutting.

    PubMed

    Glassford, Eric; Burr, Gregory

    2018-01-01

    The Health Hazard Evaluation Program of the National Institute for Occupational Safety and Health evaluated a steel building materials manufacturer. The employer requested the evaluation because of concerns about optical radiation hazards from a plasma arc cutting system and the need to clarify eye protection requirements for plasma operators, other employees, and visitors. The strength of the ultraviolet radiation, visible radiation (light), and infrared radiation generated by the plasma arc cutter was measured at various distances from the source and at different operating amperages. Investigators also observed employees performing the plasma arc cutting. Optical radiation above safe levels for the unprotected eyes in the ultraviolet-C, ultraviolet-B, and visible light ranges were found during plasma arc cutting. In contrast, infrared and ultraviolet-A radiation levels during plasma arc cutting were similar to background levels. The highest non-ionizing radiation exposures occurred when no welding curtains were used. A plasma arc welding curtain in place did not eliminate optical radiation hazards to the plasma arc operator or to nearby employees. In most instances, the measured intensities for visible light, UV-C, and UV-B resulted in welding shade lens numbers that were lower than those stipulated in the OSHA Filter Lenses for Protection Against Radiant Energy table in 29 CFR 1910.133(a)(5). [1] Investigators recommended using a welding curtain that enclosed the plasma arc, posting optical radiation warning signs in the plasma arc cutter area, installing audible or visual warning cues when the plasma arc cutter was operating, and using welding shades that covered the plasma arc cutter operator's face to protect skin from ultraviolet radiation hazards.

  10. Heat and metal transfer in gas metal arc welding using argon and helium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Joensson, P.G.; Eagar, T.W.; Szekely, J.

    1995-04-01

    This article describes a theoretical investigation on the arc parameters and metal transfer in gas metal arc welding (GMAW) of mild steel using argon and helium shielding gases. Major differences in the predicted arc parameters were determined to be due to large differences in thermophysical properties. Various findings from the study include that an arc cannot be struck in a pure helium atmosphere without the assistance of metal vapor, that a strong electromagnetic cathode force affects the fluid flow and heat transfer in the helium arc, providing a possible explanation for the experimentally observed globular transfer mode and that themore » tapering of t electrode in an argon arc is caused by electron condensation on the side of the electrode.« less

  11. Physicochemical Characterization of Aerosol Generated in the Gas Tungsten Arc Welding of Stainless Steel.

    PubMed

    Miettinen, Mirella; Torvela, Tiina; Leskinen, Jari T T

    2016-10-01

    Exposure to stainless steel (SS) welding aerosol that contain toxic heavy metals, chromium (Cr), manganese (Mn), and nickel (Ni), has been associated with numerous adverse health effects. The gas tungsten arc welding (GTAW) is commonly applied to SS and produces high number concentration of substantially smaller particles compared with the other welding techniques, although the mass emission rate is low. Here, a field study in a workshop with the GTAW as principal welding technique was conducted to determine the physicochemical properties of the airborne particles and to improve the understanding of the hazard the SS welding aerosols pose to welders. Particle number concentration and number size distribution were measured near the breathing zone (50cm from the arc) and in the middle of the workshop with condensation particle counters and electrical mobility particle sizers, respectively. Particle morphology and chemical composition were studied using scanning and transmission electron microscopy and energy-dispersive X-ray spectroscopy. In the middle of the workshop, the number size distribution was unimodal with the geometric mean diameter (GMD) of 46nm. Near the breathing zone the number size distribution was multimodal, and the GMDs of the modes were in the range of 10-30nm. Two different agglomerate types existed near the breathing zone. The first type consisted of iron oxide primary particles with size up to 40nm and variable amounts of Cr, Mn, and Ni replacing iron in the structure. The second type consisted of very small primary particles and contained increased proportion of Ni compared to the proportion of (Cr + Mn) than the first agglomerate type. The alterations in the distribution of Ni between different welding aerosol particles have not been reported previously. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  12. The influence of cooling parameters on the speed of continuous steel casting

    NASA Astrophysics Data System (ADS)

    Tirian, G. O.; Gheorghiu, C. A.; Hepuţ, T.; Chioncel, C. P.

    2018-01-01

    This paper analyzes the cooling parameters of the continuous casting speed. In the researches carried out we aimed to establish some correlation equations between the parameters characterizing the continuous casting process, the temperature of the steel at the entrance to the crystallizer, the superheating of the steel and the flow of the cooling water in the crystallizer and different zones of the secondary cooling. Parallel to these parameters were also the values for the casting speed. The research was made for the casting of round ϕ270mm semi-finished steel products. The steel was developed in an electric EBT furnace with a capacity of 100t, treated in L.F. (Ladle - Furnace) and VD (Vacuum-Degassing) and poured in a 5-wire continuous casting plant. The obtained data was processed in MATLAB using three types of correlation equations. The obtained results are presented both in the analytical and graphical form, each correlation being analyzed from the technological point of view, indicating the optimal values for the independent parameters monitored. In the analysis we present a comparison between the results obtained after the three types of equations for each correlation.

  13. 77 FR 32562 - Circular Welded Carbon-Quality Steel Pipe From India: Preliminary Determination of Sales at Less...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ...: Steel Concrete Reinforcing Bars From Poland, Indonesia, and Ukraine, 66 FR 8343, 8346 (January 30, 2001) (unchanged in Notice of Final Determinations of Sales at Less Than Fair Value: Steel Concrete Reinforcing..., heat exchangers, refining furnaces and feedwater heaters, whether or not cold drawn; (b) finished...

  14. Alkali activated slag mortars provide high resistance to chloride-induced corrosion of steel

    NASA Astrophysics Data System (ADS)

    Criado, Maria; Provis, John L.

    2018-06-01

    The pore solutions of alkali-activated slag cements and Portland-based cements are very different in terms of their chemical and redox characteristics, particularly due to the high alkalinity and high sulfide content of alkali-activated slag cement. Therefore, differences in corrosion mechanisms of steel elements embedded in these cements could be expected, with important implications for the durability of reinforced concrete elements. This study assesses the corrosion behaviour of steel embedded in alkali-activated blast furnace slag (BFS) mortars exposed to alkaline solution, alkaline chloride-rich solution, water, and standard laboratory conditions, using electrochemical techniques. White Portland cement (WPC) mortars and blended cement mortars (white Portland cement and blast furnace slag) were also tested for comparative purposes. The steel elements embedded in immersed alkali-activated slag mortars presented very negative redox potentials and high apparent corrosion current values; the presence of sulfide reduced the redox potential, and the oxidation of the reduced sulfur-containing species within the cement itself gave an electrochemical signal that classical electrochemical tests for reinforced concrete durability would interpret as being due to steel corrosion processes. However, the actual observed resistance to chloride-induced corrosion was very high, as measured by extraction and characterisation of the steel at the end of a 9-month exposure period, whereas the steel embedded in white Portland cement mortars was significantly damaged under the same conditions.

  15. Co-reduction of Copper Smelting Slag and Nickel Laterite to Prepare Fe-Ni-Cu Alloy for Weathering Steel

    NASA Astrophysics Data System (ADS)

    Guo, Zhengqi; Pan, Jian; Zhu, Deqing; Zhang, Feng

    2018-02-01

    In this study, a new technique was proposed for the economical and environmentally friendly recovery of valuable metals from copper smelting slag while simultaneously upgrading nickel laterite through a co-reduction followed by wet magnetic separation process. Copper slag with a high FeO content can decrease the liquidus temperature of the SiO2-Al2O3-CaO-MgO system and facilitate formation of liquid phase in a co-reduction process with nickel laterite, which is beneficial for metallic particle growth. As a result, the recovery of Ni, Cu, and Fe was notably increased. A crude Fe-Ni-Cu alloy with 2.5% Ni, 1.1% Cu, and 87.9% Fe was produced, which can replace part of scrap steel, electrolytic copper, and nickel as the burden in the production of weathering steel by an electric arc furnace. The study further found that an appropriate proportion of copper slag and nickel laterite in the mixture is essential to enhance the reduction, acquire appropriate amounts of the liquid phase, and improve the growth of the metallic alloy grains. As a result, the liberation of alloy particles in the grinding process was effectively promoted and the metal recovery was increased significantly in the subsequent magnetic separation process.

  16. Time-dependent calculations of molten pool formation and thermal plasma with metal vapour in gas tungsten arc welding

    NASA Astrophysics Data System (ADS)

    Tanaka, M.; Yamamoto, K.; Tashiro, S.; Nakata, K.; Yamamoto, E.; Yamazaki, K.; Suzuki, K.; Murphy, A. B.; Lowke, J. J.

    2010-11-01

    A gas tungsten arc (GTA) was modelled taking into account the contamination of the plasma by metal vapour from the molten anode. The whole region of GTA atmosphere including the tungsten cathode, the arc plasma and the anode was treated using a unified numerical model. A viscosity approximation was used to express the diffusion coefficient in terms of viscosity of the shielding gas and metal vapour. The transient two-dimensional distributions of temperature, velocity of plasma flow and iron vapour concentration were predicted, together with the molten pool as a function of time for a 150 A arc current at atmospheric pressure, both for helium and argon gases. It was shown that the thermal plasma in the GTA was influenced by iron vapour from the molten pool surface and that the concentration of iron vapour in the plasma was dependent on the temperature of the molten pool. GTA on high sulfur stainless steel was calculated to discuss the differences between a low sulfur and a high sulfur stainless steel anode. Helium was selected as the shielding gas because a helium GTA produces more metal vapour than an argon GTA. In the GTA on a high sulfur stainless steel anode, iron vapour and current path were constricted. Radiative emission density in the GTA on high sulfur stainless steel was also concentrated in the centre area of the arc plasma together with the iron vapour although the temperature distributions were almost the same as that in the case of a low sulfur stainless steel anode.

  17. Looking north at uing press of the submerged arc weld ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking north at u-ing press of the submerged arc weld (saw) line of the main pipe mill building, bay 7. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  18. Influence of Filler Wire Feed Rate in Laser-Arc Hybrid Welding of T-butt Joint in Shipbuilding Steel with Different Optical Setups

    NASA Astrophysics Data System (ADS)

    Unt, Anna; Poutiainen, Ilkka; Salminen, Antti

    In this paper, a study of laser-arc hybrid welding featuring three different process fibres was conducted to build knowledge about process behaviour and discuss potential benefits for improving the weld properties. The welding parameters affect the weld geometry considerably, as an example the increase in welding speed usually decreases the penetration and a larger beam diameter usually widens the weld. The laser hybrid welding system equipped with process fibres with 200, 300 and 600 μm core diameter were used to produce fillet welds. Shipbuilding steel AH36 plates with 8 mm thickness were welded with Hybrid-Laser-Arc-Welding (HLAW) in inversed T configuration, the effects of the filler wire feed rate and the beam positioning distance from the joint plane were investigated. Based on the metallographic cross-sections, the effect of process parameters on the joint geometry was studied. Joints with optimized properties (full penetration, soundness, smooth transition from bead to base material) were produced with 200 μm and 600 μm process fibres, while fiber with 300 μm core diameter produced welds with unacceptable levels of porosity.

  19. Computational Modeling of Microstructural-Evolution in AISI 1005 Steel During Gas Metal Arc Butt Welding

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Ramaswami, S.; Snipes, J. S.; Yavari, R.; Arakere, A.; Yen, C.-F.; Cheeseman, B. A.

    2013-05-01

    A fully coupled (two-way), transient, thermal-mechanical finite-element procedure is developed to model conventional gas metal arc welding (GMAW) butt-joining process. Two-way thermal-mechanical coupling is achieved by making the mechanical material model of the workpiece and the weld temperature-dependent and by allowing the potential work of plastic deformation resulting from large thermal gradients to be dissipated in the form of heat. To account for the heat losses from the weld into the surroundings, heat transfer effects associated with natural convection and radiation to the environment and thermal-heat conduction to the adjacent workpiece material are considered. The procedure is next combined with the basic physical-metallurgy concepts and principles and applied to a prototypical (plain) low-carbon steel (AISI 1005) to predict the distribution of various crystalline phases within the as-welded material microstructure in different fusion zone and heat-affected zone locations, under given GMAW-process parameters. The results obtained are compared with available open-literature experimental data to provide validation/verification for the proposed GMAW modeling effort.

  20. Maintenance of Low-Pressure Carburising Furnaces: A Source of PAH Exposure.

    PubMed

    Champmartin, Catherine; Jeandel, Fanny; Monnier, Hubert

    2017-04-01

    Low-pressure carburising is a new technology used to harden steel; the process has been shown to be a source of considerable polycyclic aromatic hydrocarbons (PAH) pollution. Some PAH are carcinogenic, and activities such as furnace maintenance may thus represent a risk to workers. Occupational exposure during these operations should therefore be assessed. In this study, the PAH-related carcinogenic risk associated with furnace maintenance was assessed by monitoring atmospheric levels of benzo[a]pyrene (BaP), a representative marker, alongside urinary levels of 3-hydroxybenzo[a]pyrene (3-OHBaP), one of its metabolites. PAH exposure levels were monitored during seven sampling campaigns in four different factories specialized in heat-treatment of mechanical workpieces for the automotive and helicopter industries. Two types of furnace were studied, and 37 individuals were monitored. Values up to 20-fold the French regulatory value of 150 ng/m3 for atmospheric BaP, and, for urinary 3-OHBaP values up to 40-fold the French biological limit value (BLV) of 0.35 nmol/mol of creatinine were detected. Very high concentrations of BaP, close to or even exceeding those found in coal-tar pitch (up to about 20 g/kg), were measured in residues (tars, dusts) deposited inside the furnace. Even when adequate and suitable personal protective equipment was used, urinary 3-OHBaP values often exceeded the BLV. We hypothesize that this exposure is linked to insidious and fortuitous dermal contamination through contact with factory equipment and staining. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  1. Laser-Arc Hybrid Welding of Dissimilar Titanium Alloy and Stainless Steel Using Copper Wire

    NASA Astrophysics Data System (ADS)

    Gao, Ming; Chen, Cong; Wang, Lei; Wang, Zemin; Zeng, Xiaoyan

    2015-05-01

    Laser-arc hybrid welding with Cu3Si filler wire was employed to join dissimilar Ti6Al4V titanium alloy and AISI316 stainless steel (316SS). The effects of welding parameters on bead shape, microstructure, mechanical properties, and fracture behavior were investigated in detail. The results show that cross-weld tensile strength of the joints is up to 212 MPa. In the joint, obvious nonuniformity of the microstructure is found in the fusion zone (FZ) and at the interfaces from the top to the bottom, which could be improved by increasing heat input. For the homogeneous joint, the FZ is characterized by Fe67- x Si x Ti33 dendrites spreading on α-Cu matrix, and the two interfaces of 316SS/FZ and FZ/Ti6Al4V are characterized by a bamboo-like 316SS layer and a CuTi2 layer, respectively. All the tensile samples fractured in the hardest CuTi2 layer at Ti6Al4V side of the joints. The fracture surface is characterized by river pattern revealing brittle cleavage fracture. The bead formation mechanisms were discussed according to the melt flow and the thermodynamic calculation.

  2. "2sDR": Process Development of a Sustainable Way to Recycle Steel Mill Dusts in the 21st Century

    NASA Astrophysics Data System (ADS)

    Rösler, Gernot; Pichler, Christoph; Antrekowitsch, Jürgen; Wegscheider, Stefan

    2014-09-01

    Significant amounts of electric arc furnace dust originating from steel production are recycled every year by the Waelz process, despite the fact that this type of process has several disadvantages. One alternative method would be the recovery of very high-quality ZnO as well as iron and even chromium in the two-step dust recycling process, which was invented to treat special waste for the recovery of heavy metal-containing residues. The big advantage of that process is that various types of residues, especially dusts, can be treated in an oxidizing first step for cleaning, with a subsequent reducing step for the metal recovery. After the treatment, three different fractions—dust, slag, and an iron alloy, can be used without any limitations. This study focuses on the development of the process along with some thermodynamic considerations. Moreover, a final overview of mass balances of an experiment performed in a 100-kg top blowing rotary converter with further developments is provided.

  3. Characterization of airborne and bulk particulate from iron and steel manufacturing facilities.

    PubMed

    Machemer, Steven D

    2004-01-15

    Characterization of airborne and bulk particulate material from iron and steel manufacturing facilities, commonly referred to as kish, indicated graphite flakes and graphite flakes associated with spherical iron oxide particles were unique particle characteristics useful in identifying particle emissions from iron and steel manufacturing. Characterization of airborne particulate material collected in receptor areas was consistent with multiple atmospheric release events of kish particles from the local iron and steel facilities into neighboring residential areas. Kish particles deposited in nearby residential areas included an abundance of graphite flakes, tens of micrometers to millimeters in size, and spherical iron oxide particles, submicrometer to tens of micrometers in size. Bulk kish from local iron and steel facilities contained an abundance of similar particles. Approximately 60% of blast furnace kish by volume consisted of spherical iron oxide particles in the respirable size range. Basic oxygen furnace kish contained percent levels of strongly alkaline components such as calcium hydroxide. In addition, concentrations of respirable Mn in airborne particulate in residential areas and at local iron and steel facilities were approximately 1.6 and 53 times the inhalation reference concentration of 0.05 microg/m3 for chronic inhalation exposure of Mn, respectively. Thus, airborne release of kish may pose potential respirable particulate, corrosive, or toxic hazards for human health and/or a corrosive hazard for property and the environment.

  4. Determination of trace and minor elements in alloys by atomic-absorption spectroscopy using an induction-heated graphite-well furnace as atom source-II.

    PubMed

    Ashy, M A; Headridge, J B; Sowerbutts, A

    1974-06-01

    Results are presented for the atomic-absorption spectrophotometric determination of zinc in aluminium and aluminium-silicon alloys, and aluminium, antimony and tin in steels, by means of solid samples dropped into an induction-heated graphite-well furnace to produce the atomic vapour.

  5. Incorporation of PCI flow measurement/control at AK Steel Corporation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dibert, W.A.; Keaton, D.

    1994-12-31

    A measurement and control system has been developed and implemented to improve the distribution of coal among the tuyere lines on AK Steel Corporation`s Amanda blast furnace at Ashland, Kentucky. This paper discusses the development and design of the system, and briefly reviews operating results achieved.

  6. Fatigue crack growth behavior of pressure vessel steels and submerged arc weldments in a high-temperature pressurized water environment

    NASA Astrophysics Data System (ADS)

    Liaw, P. K.; Logsdon, W. A.; Begley, J. A.

    1989-10-01

    The fatigue crack growth rate (FCGR) properties of SA508 C1 2a and SA533 Gr A C1 2 pressure vessel steels and the corresponding automatic submerged are weldments were developed in a high-temperature pressurized water (HPW) environment at 288 °C (550°F) and 7.2 MPa (1044 psi) at load ratios of 0.02 and 0.50. The HPW enviromment FCGR properties of these pressure vessel steels and submerged arc weldments were generally conservative, compared with the approrpriate American Society of Mechanical Engineers (ASME) Section XI water environmental reference curve. The growth rate of fatigue cracks in the base materials, however, was considerably faster in the HPW environment than in a corresponding 288°C (550°F) base line air environment. The growth rate of fatigue cracks in the two submerged are weldments was also accelerated in the HPW environment but to a significantly lesser degree than that demonstrated by the corresponding base materials. In the air environment, fatigue striations were observed, independent of material and load ratio, while in the HPW environment, some intergranular facets were present. The greater environmental effect on crack growth rates displayed by the base materials, as compared with the weldments, was attributed to a different sulfide composition and morphology.

  7. Process Simulation of Gas Metal Arc Welding Software

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murray, Paul E.

    2005-09-06

    ARCWELDER is a Windows-based application that simulates gas metal arc welding (GMAW) of steel and aluminum. The software simulates the welding process in an accurate and efficient manner, provides menu items for process parameter selection, and includes a graphical user interface with the option to animate the process. The user enters the base and electrode material, open circuit voltage, wire diameter, wire feed speed, welding speed, and standoff distance. The program computes the size and shape of a square-groove or V-groove weld in the flat position. The program also computes the current, arc voltage, arc length, electrode extension, transfer ofmore » droplets, heat input, filler metal deposition, base metal dilution, and centerline cooling rate, in English or SI units. The simulation may be used to select welding parameters that lead to desired operation conditions.« less

  8. Prereduction and melting of domestic titaniferous materials

    NASA Astrophysics Data System (ADS)

    Nafziger, R. H.; Jordan, R. R.

    1983-03-01

    Two domestic ilmenites and one titaniferous magnetite were prereduced by the United States Department of the Interior, Bureau of Mines, in a batch rotary kiln with coal char to assess the feasibility of this technique in improving melting operations and subsequent electric furnace processing. All three prereduced titaniferous materials were melted satisfactorily in an electric arc furnace to produce iron as a metal suitable for further refining to steel; metallizations ranging from 63 to 83 pct of the iron oxides were achieved. The ilmenites yielded titanium enriched slags that were amenable to further processing by conventional methods. Prereduction decreased electrode consumption during furnace operation and also conserved expensive electrical energy that otherwise must be used to reduce and melt totally the entire titaniferous materials charge.

  9. Oxidation behavior and electrical property of ferritic stainless steel interconnects with a Cr-La alloying layer by high-energy micro-arc alloying process

    NASA Astrophysics Data System (ADS)

    Feng, Z. J.; Zeng, C. L.

    Chromium volatility, poisoning of the cathode material and rapidly decreasing electrical conductivity are the major problems associated with the application of ferritic stainless steel interconnects of solid oxide fuel cells operated at intermediate temperatures. Recently, a novel and simple high-energy micro-arc alloying (HEMAA) process is proposed to prepare LaCrO 3-based coatings for the type 430 stainless steel interconnects using a LaCrO 3-Ni rod as deposition electrode. In this work, a Cr-La alloying layer is firstly obtained on the alloy surface by HEMAA using Cr and La as deposition electrode, respectively, followed by oxidation treatment at 850 °C in air to form a thermally grown LaCrO 3 coating. With the formation of a protective scale composed of a thick LaCrO 3 outer layer incorporated with small amounts of Cr-rich oxides and a thin Cr 2O 3-rich sub-layer, the oxidation rate of the coated steel is reduced remarkably. A low and stable electrical contact resistance is achieved with the application of LaCrO 3-based coatings, with a value less than 40 mΩ cm 2 during exposure at 850 °C in air for up to 500 h.

  10. TiC reinforced cast Cr steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dogan, O.N.; Hawk, J.A.; Schrems, K.K.

    2006-06-01

    A new class of materials, namely TiC-reinforced cast chromium (Cr) steels, was developed for applications requiring high abrasion resistance and good fracture toughness. The research approach was to modify the carbide structure of commercial AISI 440C steel for better fracture resistance while maintaining the already high abrasion resistance. The new alloys contained 12Cr, 2.5–4.5Ti, and 1–1.5C (wt.%) and were melted in a vacuum induction furnace. Their microstructure was composed primarily of a martensitic matrix with a dispersion of TiC precipitates. Modification of TiC morphology was accomplished through changing the cooling rate during solidification. Wear rates of the TiC-reinforced Cr steelsmore » were comparable to that of AISI 440C steel, but the impact resistance was much improved.« less

  11. 49 CFR 192.113 - Longitudinal joint factor (E) for steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... class Longitudinal joint factor (E) ASTM A 53/A53M Seamless 1.00 Electric resistance welded 1.00 Furnace butt welded .60 ASTM A 106 Seamless 1.00 ASTM A 333/A 333M Seamless 1.00 Electric resistance welded 1.00 ASTM A 381 Double submerged arc welded 1.00 ASTM A 671 Electric-fusion-welded 1.00 ASTM A 672...

  12. Shielding gas effect on weld characteristics in arc-augmented laser welding process of super austenitic stainless steel

    NASA Astrophysics Data System (ADS)

    Sathiya, P.; Kumar Mishra, Mahendra; Soundararajan, R.; Shanmugarajan, B.

    2013-02-01

    A series of hybrid welding (gas metal arc welding-CO2 laser beam welding) experiments were conducted on AISI 904L super austenitic stainless steel sheet of 5 mm thickness. A detailed study of CO2 Laser-GMAW hybrid welding experiments with different shielding gas mixtures (100% He, 50% He+50% Ar, 50%He+45% Ar+5% O2, and 45% He+45% Ar+10% N2) were carried out and the results are presented. The resultant welds were subjected to detailed mechanical and microstructural characterization. Hardness testing revealed that the hardness values in the fusion zone were higher than the base material irrespective of the parameters. Transverse tensile testing showed that the joint efficiency is 100% with all the shielding gas experimented. Impact energy values of the welds were also found to be higher than the base material and the fractrograph taken in scanning electron microscope (SEM) has shown that the welds exhibited dimple fracture similar to the base material.

  13. [Measurement of chemical agents in metallurgy field: electric steel plant].

    PubMed

    Cottica, D; Grignani, E; Ghitti, R; Festa, D; Apostoli, P

    2012-01-01

    The steel industry maintains its important position in the context of the Italian production involving thousands of workers. The iron and steel processes are divided into primary steel industry, production of intermediate minerals, and secondary steel, scrap from the production of semi-finished industrial and consumer sector (metal inserted into components and metal used for dissipative uses, primarily coatings) and industrial waste. The paper presents the results of environmental monitoring carried out in some electric steel plant for the measurement of airborne chemicals that characterize the occupational exposure of workers employed in particular area like electric oven, to treatment outside the furnace, continuous casting area. For the sampling of the pollutants were used both personal and in fixed positions samplers. The pollutants measured are those typical of steel processes inhalable dust, metals, respirable dust, crystalline silica, but also Polycyclic Aromatic Hydrocarbons (PAH), polychlorinated dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs).

  14. Variable frequency microwave furnace system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal inputmore » to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.« less

  15. Variable frequency microwave furnace system

    DOEpatents

    Bible, D.W.; Lauf, R.J.

    1994-06-14

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  16. Electrostatic Levitation Furnace for the ISS

    NASA Technical Reports Server (NTRS)

    Murakami, Keiji; Koshikawa, Naokiyo; Shibasaki, Kohichi; Ishikawa, Takehiko; Okada, Junpei; Takada, Tetsuya; Arai, Tatsuya; Fujino, Naoki; Yamaura, Yukiko

    2012-01-01

    JAXA (Japan Aerospace Exploration Agency) has just started the development of Electrostatic Levitation Furnace to be launched in 2014 for the ISS. This furnace can control the sample position with electrostatic force and heat it above 2000 degree Celsius using semiconductor laser from four different directions. The announcement of Opportunity will be issued soon for this furnace. In this paper, we will show the specifications of this furnace and also the development schedule

  17. Ferronickel Preparation from Nickeliferous Laterite by Rotary Kiln-Electric Furnace Process

    NASA Astrophysics Data System (ADS)

    Li, Guanghui; Jia, Hao; Luo, Jun; Peng, Zhiwei; Zhang, Yuanbo; Jiang, Tao

    Nickel is an important strategic metal, which is mainly used for stainless steel production. In the recent years, ferronickel has been used as a substitute for electrolytic nickel for alleviating the cost of stainless steel production. Rotary kiln-electric furnace (RKEF) smelting is currently the world-wide mainstreaming process for ferronickel production from nickeliferous laterite ore, in spite of the high power consumption. In this study, aiming to provide some meaningful guidance for ferronickel production of RKEF smelting, reductive roasting followed by smelting process was carried out. The conditions including reducing parameters (roasting temperature and time) and smelting parameters (coke dosage, CaO dosage, melting temperature and time) were ascertained. The metal recovery ratios, as well as Ni, Fe, S and P content of ferronickel were considered. The results showed that a ferronickel containing 10. 32 wt. % Ni was obtained from a laterite with 1. 85 wt. % Ni, the nickel recovery ratio was about 99%.

  18. Experimental investigation of basic oxygen furnace slag used as aggregate in asphalt mixture.

    PubMed

    Xue, Yongjie; Wu, Shaopeng; Hou, Haobo; Zha, Jin

    2006-11-16

    Chinese researchers have commenced a great deal of researches on the development of application fields of basic oxygen steel making furnace slag (BOF slag) for many years. Lots of new applications and properties have been found, but few of them in asphalt mixture of road construction engineering. This paper discussed the feasibility of BOF steel slag used as aggregate in asphalt pavement by two points of view including BOF steel slag's physical and micro-properties as well as steel slag asphalt materials and pavement performances. For the former part, this paper mainly concerned the mechanochemistry and physical changes of the steel slag and studied it by performing XRD, SEM, TG and mercury porosimeter analysis and testing method. In the second part, this paper intended to use BOF steel slag as raw material, and design steel slag SMA mixture. By using traditional rutting test, soak wheel track and modified Lottman test, the high temperature stability and water resistance ability were tested. Single axes compression test and indirect tensile test were performed to evaluate the low temperature crack resistance performance and fatigue characteristic. Simultaneously, by observing steel slag SMA pavement which was paved successfully. A follow-up study to evaluate the performance of the experimental pavement confirmed that the experimental pavement was comparable with conventional asphalt pavement, even superior to the later in some aspects. All of above test results and analysis had only one main purpose that this paper validated the opinion that using BOF slag in asphalt concrete is feasible. So this paper suggested that treated and tested steel slag should be used in a more extensive range, especially in asphalt mixture paving projects in such an abundant steel slag resource region.

  19. Keyhole behavior and liquid flow in molten pool during laser-arc hybrid welding

    NASA Astrophysics Data System (ADS)

    Naito, Yasuaki; Katayama, Seiji; Matsunawa, Akira

    2003-03-01

    Hybrid welding was carried out on Type 304 stainless steel plate under various conditions using YAG laser combined with TIG arc. During arc and laser-arc hybrid welding, arc voltage variation was measured, and arc plasma, laser-induced plume and evaporation spots as well as keyhole behavior and liquid flow in the molten pool were observed through CCD camera and X-ray real-time transmission apparatus. It was consequently found that hybrid welding possessed many features in comparison with YAG laser welding. The deepest weld bead could be produced when the YAG laser beam of high power density was shot on the molten pool made beforehand stably with TIG arc. A keyhole was long and narrow, and its behavior was rather stable inside the molten pool. It was also confirmed that porosity was reduced by the suppression of bubble formation in hybrid welding utilizing a laser of a moderate power density.

  20. Use of soil-steel slag-class-C fly ash mixtures in subgrade applications.

    DOT National Transportation Integrated Search

    2012-12-07

    In Indiana, large quantities of recyclable : materials - such as steel slag, blast furnace : slag and fly ash - are generated each year as : by-products of various industries. Instead of : disposing these by-products into landfills, : we can recycle ...

  1. Complex technology of vacuum-arc processing of structural material surface

    NASA Astrophysics Data System (ADS)

    Arustamov, V. N.; Ashurov, Kh. B.; Kadyrov, Kh. Kh.; Khudoikulov, I. Kh.

    2015-08-01

    The development of environmentally friendly and energy-resource-saving technologies based on vacuum arc discharge is a topical problem in science and engineering. In view of their unique properties, cathode spots of a vacuum arc induce cleaning of the surface of an article (cathode) from various contaminations and pulsed thermal action on the surface layers. These processes occur in complex with vacuum-arc deposition of coatings in the same technological cycle, which makes it possible to considerably increase the efficiency of methods for changing physical, mechanical, and chemical properties of the surface of steel articles, which considerably increase their service life. Analysis of the formation of the temperature regime of the surface during vacuum arc action and of the parameters of the deposited coating will make it possible to optimize the regimes of complex treatment of the surfaces of articles and is of considerable theoretical and practical importance.

  2. 46 CFR 164.009-11 - Furnace apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Furnace apparatus. 164.009-11 Section 164.009-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... apparatus. (a) The test furnace apparatus consists of a furnace tube, stabilizer, draft shield, furnace...

  3. 46 CFR 164.009-11 - Furnace apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Furnace apparatus. 164.009-11 Section 164.009-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS... apparatus. (a) The test furnace apparatus consists of a furnace tube, stabilizer, draft shield, furnace...

  4. Improved Heat Treatment Of Steel Alloy 4340

    NASA Technical Reports Server (NTRS)

    Cooper, Lawrence B.

    1993-01-01

    New process takes significantly less time than prior heat-treatment processes. Involves placing steel plate directly in furnace and heat-treating. Plate then quenched in slowly moving oil to reduce stresses. Any deflection then pressed out. Possible uses of 4340 steel include new and improved bulletproof vests for military and police personnel and armor for bulletproof automobiles for military, police, diplomatic, and private users. Also used in other military land vehicles as tanks and in both military and civilian aircraft. Lighter armorplate enables land vehicles and aircraft to attain greater speed and maneuverability, consume less fuel, and afford better protection from snipers or terrorists.

  5. Studies on microstructure, mechanical and corrosion properties of high nitrogen stainless steel shielded metal arc welds

    NASA Astrophysics Data System (ADS)

    Mohammed, Raffi; Madhusudhan Reddy, G.; Srinivasa Rao, K.

    2018-03-01

    The present work is aimed at studying the microstructure, mechanical and corrosion properties of high nitrogen stainless steel shielded metal arc (SMA) welds made with Cromang-N electrode. Basis for selecting this electrode is to increase the solubility of nitrogen in weld metal due to high chromium and manganese content. Microstructures of the welds were characterized using optical microscopy (OM), field emission scanning electron microscopy (FESEM) and electron back scattered diffraction (EBSD) mainly to determine the morphology, phase analysis, grain size and orientation image mapping. Hardness, tensile and ductility bend tests were carried out to determine mechanical properties. Potentio-dynamic polarization testing was carried out to study the pitting corrosion resistance using a GillAC basic electrochemical system. Constant load type testing was carried out to study stress corrosion cracking (SCC) behaviour of welds. The investigation results shown that the selected Cr–Mn–N type electrode resulted in favourable microstructure and completely solidified as single phase coarse austenite. Mechanical properties of SMA welds are found to be inferior when compared to that of base metal and is due to coarse and dendritic structure.

  6. Study of Nanodispersed Iron Oxides Produced in Steel Drilling by Contracted Electric-Arc Air Plasma Torch

    NASA Astrophysics Data System (ADS)

    Stefanov, P.; Galanov, D.; Vissokov, G.; Paneva, D.; Kunev, B.; Mitov, I.

    2008-06-01

    The optimal conditions on the plasma-forming gas flowrate, discharge current and voltage, distance between the plasma-torch nozzle and the metal plate surface for the process of penetration in and vaporization of steel plates by the contracted electric-arc air plasma torch accompanied by water quenching, were determined. The X-ray structural and phase studies as well as Mössbauer and electron microscope studies on the samples treated were performed. It was demonstrated that the vaporized elemental iron was oxidized by the oxygen present in the air plasma jet to form iron oxides (wüstite, magnetite, hematite), which, depending on their mass ratios, determined the color of the iron oxide pigments, namely, beginning from light yellow, through deep yellow, light brown, deep brown, violet, red-violet, to black. A high degree of dispersity of the iron oxides is thus produced, with an averaged diameter of the particles below 500 nm, and their defective crystal structure form the basis of their potential application as components of iron-containing catalysts and pigments.

  7. The adaption of coal quality to furnace structure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Z.; Shun, X.

    1996-12-31

    This paper gives the research result of coal quality adaption to furnace structure. The designing of a furnace is based on the coal quality that the furnace would fire. If the coal fired in the furnace differs from the design coal, there would be a lot of problems such as flame stability, coal burn-out rate and slagging problem for the furnace during its operation. In order to know the adaptional range of coal quality for an existing furnace the authors had chosen three different furnaces and 18 kinds of coals in their research work. To understand the coal combustion characteristicsmore » they introduce different indexes to show different processes of coal combustion. These indexes include Fz index which demonstrates the coal combustion based on its utility analyzed result, flame stability index, combustion characteristic index and char burn-out index which are based on the analyzed result of thermogravimetric characteristic. As a furnace is built up and set into operation its flame stability, burn-out rate and ash deposition are definite. If a furnace`s fuel changes its structure characteristics and operation condition will change. A relation between coal quality to furnace structure is based on a lot of regressional analysis results of existing furnaces and their fuels. Based on this relation the adaption of coal quality for a furnace are defined and the kinds of coal furnace fired are optimized to its design fuel.« less

  8. HIGH TEMPERATURE MICROSCOPE AND FURNACE

    DOEpatents

    Olson, D.M.

    1961-01-31

    A high-temperature microscope is offered. It has a reflecting optic situated above a molten specimen in a furnace and reflecting the image of the same downward through an inert optic member in the floor of the furnace, a plurality of spaced reflecting plane mirrors defining a reflecting path around the furnace, a standard microscope supported in the path of and forming the end terminus of the light path.

  9. Reproducing ten years of road ageing--accelerated carbonation and leaching of EAF steel slag.

    PubMed

    Suer, Pascal; Lindqvist, Jan-Erik; Arm, Maria; Frogner-Kockum, Paul

    2009-09-01

    Reuse of industrial aggregates is still hindered by concern for their long-term properties. This paper proposes a laboratory method for accelerated ageing of steel slag, to predict environmental and technical properties, starting from fresh slag. Ageing processes in a 10-year old asphalt road with steel slag of electric arc furnace (EAF) type in the subbase were identified by scanning electron microscopy (SEM) and leaching tests. Samples from the road centre and the pavement edge were compared with each other and with samples of fresh slag. It was found that slag from the pavement edge showed traces of carbonation and leaching processes, whereas the road centre material was nearly identical to fresh slag, in spite of an accessible particle structure. Batches of moisturized road centre material exposed to oxygen, nitrogen or carbon dioxide (CO2) were used for accelerated ageing. Time (7-14 days), temperature (20-40 degrees C) and initial slag moisture content (8-20%) were varied to achieve the carbonation (decrease in pH) and leaching that was observed in the pavement edge material. After ageing, water was added to assess leaching of metals and macroelements. 12% moisture, CO2 and seven days at 40 degrees C gave the lowest pH value. This also reproduced the observed ageing effect for Ca, Cu, Ba, Fe, Mn, Pb, Ca (decreased leaching) and for V, Si, and Al (increased leaching). However, ageing effects on SO4, DOC and Cr were not reproduced.

  10. Variable frequency microwave furnace system

    DOEpatents

    Bible, Don W.; Lauf, Robert J.

    1994-01-01

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  11. Effects of thin-film accelerated carbonation on steel slag leaching.

    PubMed

    Baciocchi, R; Costa, G; Polettini, A; Pomi, R

    2015-04-09

    This paper discusses the effects of accelerated carbonation on the leaching behaviour of two types of stainless steel slags (electric arc furnace and argon oxygen decarburisation slag). The release of major elements and toxic metals both at the natural pH and at varying pH conditions was addressed. Geochemical modelling of the eluates was used to theoretically describe leaching and derive information about mineralogical changes induced by carbonation. Among the investigated elements, Ca and Si were most appreciably affected by carbonation. A very clear effect of carbonation on leaching was observed for silicate phases; geochemical modelling indicated that the Ca/Si ratio of Ca-controlling minerals shifted from ∼ 1 for the untreated slag to 0.5-0.67 for the carbonated samples, thus showing that the carbonation process left some residual Ca-depleted silicate phases while the extracted Ca precipitated in the form of carbonate minerals. For toxic metals the changes in leaching induced by carbonation appeared to be mainly related to the resulting pH changes, which were as high as ∼ 2 orders of magnitude upon carbonation. Depending on the specific shape of the respective solubility curves, the extent of leaching of toxic metals from the slag was differently affected by carbonation. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. 40 CFR 52.1173 - Control strategy: Particulates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., Electric Arc Furnaces, Sintering Plants, Blast Furnaces, Heating and Reheating Furnaces. (2) Rules 336.1371... Basic Oxygen Furnaces, Electric Arc Furnaces, Sintering Plants, Blast Furnaces and Heating and Reheating... the receiving car itself during the pushing operation; (b) in the phrase “eight consecutive trips...

  13. 40 CFR 52.1173 - Control strategy: Particulates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., Electric Arc Furnaces, Sintering Plants, Blast Furnaces, Heating and Reheating Furnaces. (2) Rules 336.1371... Basic Oxygen Furnaces, Electric Arc Furnaces, Sintering Plants, Blast Furnaces and Heating and Reheating... the receiving car itself during the pushing operation; (b) in the phrase “eight consecutive trips...

  14. 40 CFR 52.1173 - Control strategy: Particulates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., Electric Arc Furnaces, Sintering Plants, Blast Furnaces, Heating and Reheating Furnaces. (2) Rules 336.1371... Basic Oxygen Furnaces, Electric Arc Furnaces, Sintering Plants, Blast Furnaces and Heating and Reheating... the receiving car itself during the pushing operation; (b) in the phrase “eight consecutive trips...

  15. 40 CFR 52.1173 - Control strategy: Particulates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., Electric Arc Furnaces, Sintering Plants, Blast Furnaces, Heating and Reheating Furnaces. (2) Rules 336.1371... Basic Oxygen Furnaces, Electric Arc Furnaces, Sintering Plants, Blast Furnaces and Heating and Reheating... the receiving car itself during the pushing operation; (b) in the phrase “eight consecutive trips...

  16. Study on the Fluid Flow Characteristics of Coherent Jets with CO2 and O2 Mixed Injection in Electric Arc Furnace Steelmaking Processes

    NASA Astrophysics Data System (ADS)

    Wei, Guangsheng; Zhu, Rong; Wu, Xuetao; Yang, Lingzhi; Dong, Kai; Cheng, Ting; Tang, Tianping

    2018-06-01

    As an efficient oxygen supplying technology, coherent jets are widely applied in electric arc furnace (EAF) steelmaking processes to strengthen chemical energy input, speed up smelting rhythm, and promote the uniformity of molten bath temperature and compositions. Recently, the coherent jet with CO2 and O2 mixed injection (COMI) was proposed and demonstrated great application potentiality in reducing the dust production in EAF steelmaking. In the present study, based on the eddy dissipation concept model, a computational fluid dynamics model of coherent jets with COMI was built with the overall and detailed chemical kinetic mechanisms (GRI-Mech 3.0). Compared with one-step combustion reaction, GRI-Mech 3.0 consists of 325 elementary reactions with 53 components and can predict more accurate results. The numerical simulation results were validated by the combustion experiment data. The jet behavior and the fluid flow characteristics of coherent jets with COMI under 298 K and 1700 K (25 °C and 1427 °C) were studied and the results showed that for coherent jets with COMI, the chemical effect of CO2 significantly weakened the shrouding combustion reactions of CH4 and the relative importance of the chemical effect of CO2 increases with CO2 concentration increasing. The potential core length of coherent jet decreases with the volume fraction of CO2 increasing. Moreover, it also can be found that the potential core length of coherent jets was prolonged with higher ambient temperature.

  17. Study on the Fluid Flow Characteristics of Coherent Jets with CO2 and O2 Mixed Injection in Electric Arc Furnace Steelmaking Processes

    NASA Astrophysics Data System (ADS)

    Wei, Guangsheng; Zhu, Rong; Wu, Xuetao; Yang, Lingzhi; Dong, Kai; Cheng, Ting; Tang, Tianping

    2018-03-01

    As an efficient oxygen supplying technology, coherent jets are widely applied in electric arc furnace (EAF) steelmaking processes to strengthen chemical energy input, speed up smelting rhythm, and promote the uniformity of molten bath temperature and compositions. Recently, the coherent jet with CO2 and O2 mixed injection (COMI) was proposed and demonstrated great application potentiality in reducing the dust production in EAF steelmaking. In the present study, based on the eddy dissipation concept model, a computational fluid dynamics model of coherent jets with COMI was built with the overall and detailed chemical kinetic mechanisms (GRI-Mech 3.0). Compared with one-step combustion reaction, GRI-Mech 3.0 consists of 325 elementary reactions with 53 components and can predict more accurate results. The numerical simulation results were validated by the combustion experiment data. The jet behavior and the fluid flow characteristics of coherent jets with COMI under 298 K and 1700 K (25 °C and 1427 °C) were studied and the results showed that for coherent jets with COMI, the chemical effect of CO2 significantly weakened the shrouding combustion reactions of CH4 and the relative importance of the chemical effect of CO2 increases with CO2 concentration increasing. The potential core length of coherent jet decreases with the volume fraction of CO2 increasing. Moreover, it also can be found that the potential core length of coherent jets was prolonged with higher ambient temperature.

  18. Greener durable concretes through geopolymerisation of blast furnace slag

    NASA Astrophysics Data System (ADS)

    Rajamane, N. P.; Nataraja, M. C.; Jeyalakshmi, R.; Nithiyanantham, S.

    2015-05-01

    The eco-friendliness of concrete is quantified by parameters such as ‘embodied energy’ (EE) and ‘embodied CO2 emission’ (ECO2e), besides duration of designed ‘service life’. It may be noted that ECO2e is also referred as carbon footprint (CF) in the literature. Geopolymer (GP) is an inorganic polymeric gel, a type of amorphous alumino-silicate product, which can be synthesised by polycondensation reactions. The concrete reported in this paper was prepared using industrial wastes in the form of blast furnace slag, fly ash as geopolymeric source materials and sodium silicate and sodium hydroxide as activators. Many mechanical properties such as compressive strength, chloride diffusion, steel corrosion, rapid chloride permeability test and rapid migration test are compared with Portland cement.

  19. Induction furnace testing of the durability of prototype crucibles in a molten metal environment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jablonski, Paul D.

    2005-09-01

    Engineered ceramic crucibles are commonly used to contain molten metal. Besides high temperature stability, other desired crucible characteristics include thermal shock resistance, minimal reaction with the molten metal and resistance to attack from the base metal oxide formed during melting. When used in an induction furnace, they can be employed as a “semi-permanent” crucible incorporating a dry ram backup and a ceramic cap. This report covers several 250-lb single melt crucible tests in an air melt induction furnace. These tests consisted of melting a charge of 17-4PH stainless steel, holding the charge molten for two hours before pouring off themore » heat and then subsequently sectioning the crucible to review the extent of erosion, penetration and other physical characteristics. Selected temperature readings were made throughout each melt. Chemistry samples were also taken from each heat periodically throughout the hold. The manganese level was observed to affect the rate of chromium loss in a non-linear fashion.« less

  20. An Atom-Probe Tomographic Study of Arc Welds in a Multi-Component High-Strength Low-Alloy Steel

    NASA Astrophysics Data System (ADS)

    Hunter, Allen H.; Farren, Jeffrey D.; DuPont, John N.; Seidman, David N.

    2013-04-01

    An experimental plate steel with the composition Fe-1.39Cu-2.7Ni-0.58Al-0.48Mn-0.48Si-0.065Nb-0.05C (wt pct) or alternatively Fe-1.43Cu-2.61Ni-1.21Al-0.48Mn-0.98Si-0.039Nb-0.23C at. pct has been recently produced at Northwestern University for use in Naval hull and deck applications—it is designated NUCu-140. To understand the microstructural changes occurring in NUCu-140 steel after gas-metal arc welding (GMAW), a detailed study of the heat-affected and fusion zones was performed throughout the weld cross section using microhardness, metallographic, chemical, and atom-probe tomographic analyses. Local-electrode atom-probe (LEAP) tomography was employed to measure the morphology and compositions of Cu-rich precipitates from each region. The mean radius, number density, volume fraction, and compositions of the precipitates, as well as the interfacial concentration profiles, are measured. The Cu precipitates dissolve partially from the heat-affected zone (HAZ) thermal cycle, and freshly formed sub-nanometer radius Cu-rich precipitates nucleate in both the HAZ and fusion zone (FZ) during cooling; however, the precipitation of Cu during cooling in the HAZ and FZ is not sufficient to restore the lost strength. The precipitation in the FZ is reduced compared to the HAZ due to a mismatched Cu composition of the weld. Multi-pass welding is suggested to restore strength in the GMAW sample by promoting Cu precipitate nucleation and growth in the HAZ and FZ.

  1. List of EPA Certified Forced-Air Furnaces

    EPA Pesticide Factsheets

    The EPA-Certified Forced-Air Furnace list contains EPA-certified forced-air furnaces that meet the 2015 NSPS for New Residential Wood Heaters, New Residential Hydronic Heaters and Forced-Air Furnaces.

  2. A multi-zone muffle furnace design

    NASA Technical Reports Server (NTRS)

    Rowe, Neil D.; Kisel, Martin

    1993-01-01

    A Multi-Zone Muffle-Tube Furnace was designed, built, and tested for the purpose of providing an in-house experience base with tubular furnaces for materials processing in microgravity. As such, it must not only provide the desired temperatures and controlled thermal gradients at several discrete zones along its length but must also be capable of sustaining the rigors of a Space Shuttle launch. The furnace is insulated to minimize radial and axial heat losses. It is contained in a water-cooled enclosure for purposes of dissipating un-wanted residual heat, keeping the outer surfaces of the furnace at a 'touch-safe' temperature, and providing a rugged housing. This report describes the salient features of the furnace, testing procedures and results, and concluding remarks evaluating the overall design.

  3. Determination of trace elements in metals and alloys by atomic-absorption spectroscopy using an induction-heated graphite well furnace as atom source.

    PubMed

    Headridge, J B; Smith, D R

    1972-07-01

    An induction-heated graphite furnace, coupled to a Unicam SP 90 atomic-absorption spectrometer, is described for the direct determination of trace elements in metals and alloys. The furnace is capable of operation at temperatures up to 2400 degrees , and has been used to obtain calibration graphs for the determination of ppm quantities of bismuth in lead-base alloys, cast irons and stainless steels, and for the determination of cadmium at the ppm level in zinc-base alloys. Milligram samples of the alloys were atomized directly. Calibration graphs for the determination of the elements in solutions were obtained for comparison. The accuracy and precision of the determination are presented and discussed.

  4. Modeling, simulation and control of pulsed DE-GMA welding process for joining of aluminum to steel

    NASA Astrophysics Data System (ADS)

    Zhang, Gang; Shi, Yu; Li, Jie; Huang, Jiankang; Fan, Ding

    2014-09-01

    Joining of aluminum to steel has attracted significant attention from the welding research community, automotive and rail transportation industries. Many current welding methods have been developed and applied, however, they can not precisely control the heat input to work-piece, they are high costs, low efficiency and consist lots of complex welding devices, and the generated intermetallic compound layer in weld bead interface is thicker. A novel pulsed double electrode gas metal arc welding(Pulsed DE-GMAW) method is developed. To achieve a stable welding process for joining of aluminum to steel, a mathematical model of coupled arc is established, and a new control scheme that uses the average feedback arc voltage of main loop to adjust the wire feed speed to control coupled arc length is proposed and developed. Then, the impulse control simulation of coupled arc length, wire feed speed and wire extension is conducted to demonstrate the mathematical model and predict the stability of welding process by changing the distance of contact tip to work-piece(CTWD). To prove the proposed PSO based PID control scheme's feasibility, the rapid prototyping experimental system is setup and the bead-on-plate control experiments are conducted to join aluminum to steel. The impulse control simulation shows that the established model can accurately represent the variation of coupled arc length, wire feed speed and the average main arc voltage when the welding process is disturbed, and the developed controller has a faster response and adjustment, only runs about 0.1 s. The captured electric signals show the main arc voltage gradually closes to the supposed arc voltage by adjusting the wire feed speed in 0.8 s. The obtained typical current waveform demonstrates that the main current can be reduced by controlling the bypass current under maintaining a relative large total current. The control experiment proves the accuracy of proposed model and feasibility of new control scheme

  5. A novel pulsed gas metal arc welding system with direct droplet transfer close-loop control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Q.; Li, P.; Zhang, L.

    1994-12-31

    In pulsed gas metal arc welding (GMAW), a predominant parameter that has to be monitored and controlled in real time for maintaining process stability and ensuring weld quality, is droplet transfer. Based on the close correlation between droplet transfer and arc light radiant flux in GMAW of steel and aluminum, a direct closed-loop droplet transfer control system for pulsed GMAW with arc light sensor has been developed. By sensing the droplet transfer directly via the arc light signal, a pulsed GMAW process with real and exact one-pulse, one-droplet transfer has been achieved. The novel pulsed GMAW machine consists of threemore » parts: a sensing system, a controlling system, and a welding power system. The software used in this control system is capable of data sampling and processing, parameter matching, optimum parameter restoring, and resetting. A novel arc light sensing system has been developed. The sensor is small enough to be clamped to a semiautomatic welding torch. Based on thissensingn system, a closed-loop droplet transfer control system of GMAW of steel and aluminum has been built and a commercial prototype has been made. The system is capable of keeping one-pulse, one-droplet transfer against external interferences. The welding process with this control system has been proved to be stable, quiet, with no spatter, and provide good weld formation.« less

  6. High temperature furnace

    DOEpatents

    Borkowski, Casimer J.

    1976-08-03

    A high temperature furnace for use above 2000.degree.C is provided that features fast initial heating and low power consumption at the operating temperature. The cathode is initially heated by joule heating followed by electron emission heating at the operating temperature. The cathode is designed for routine large temperature excursions without being subjected to high thermal stresses. A further characteristic of the device is the elimination of any ceramic components from the high temperature zone of the furnace.

  7. Sustained diffusive alternating current gliding arc discharge in atmospheric pressure air

    NASA Astrophysics Data System (ADS)

    Zhu, Jiajian; Gao, Jinlong; Li, Zhongshan; Ehn, Andreas; Aldén, Marcus; Larsson, Anders; Kusano, Yukihiro

    2014-12-01

    Rapid transition from glow discharge to thermal arc has been a common problem in generating stable high-power non-thermal plasmas especially at ambient conditions. A sustained diffusive gliding arc discharge was generated in a large volume in atmospheric pressure air, driven by an alternating current (AC) power source. The plasma column extended beyond the water-cooled stainless steel electrodes and was stabilized by matching the flow speed of the turbulent air jet with the rated output power. Comprehensive investigations were performed using high-speed movies measured over the plasma column, synchronized with simultaneously recorded current and voltage waveforms. Dynamic details of the novel non-equilibrium discharge are revealed, which is characterized by a sinusoidal current waveform with amplitude stabilized at around 200 mA intermediate between thermal arc and glow discharge, shedding light to the governing mechanism of the sustained spark-suppressed AC gliding arc discharge.

  8. Acidic leaching both of zinc and iron from basic oxygen furnace sludge.

    PubMed

    Trung, Zuzana Hoang; Kukurugya, Frantisek; Takacova, Zita; Orac, Dusan; Laubertova, Martina; Miskufova, Andrea; Havlik, Tomas

    2011-09-15

    During the steel production in the basic oxygen furnace (BOF), approximately 7-15 kg of dust per tonne of produced steel is generated. This dust contains approximately 1.4-3.2% Zn and 54-70% Fe. Regarding the zinc content, the BOF dust is considered to be highly problematic, and therefore new technological processes for recycling dusts and sludge from metallurgical production are still searched for. In this study the hydrometallurgical processing of BOF sludge in the sulphuric acid solutions under atmospheric pressure and temperatures up to 100 °C is investigated on laboratory scale. The influence of sulphuric acid concentration, temperature, time and liquid to solid ratio (L:S) on the leaching process was studied. The main aim of this study was to determine optimal conditions when the maximum amount of zinc passes into the solution whilst iron remains in a solid residue. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Steel slag affects pH and Si content of container substrates

    USDA-ARS?s Scientific Manuscript database

    A substrate representing a typical greenhouse potting mix was prepared using 85% sphagnum peat and 15% perlite. The substrate was filled into 10 cm wide containers. A pulverized steel slag (SS) from a basic oxygen furnace, and dolomitic limestone (DL) were amended to the base substrate at a rate o...

  10. General purpose rocket furnace

    NASA Technical Reports Server (NTRS)

    Aldrich, B. R.; Whitt, W. D. (Inventor)

    1979-01-01

    A multipurpose furnace for space vehicles used for material processing experiments in an outer space environment is described. The furnace contains three separate cavities designed to process samples of the widest possible range of materials and thermal requirements. Each cavity contains three heating elements capable of independent function under the direction of an automatic and programmable control system. A heat removable mechanism is also provided for each cavity which operates in conjunction with the control system for establishing an isothermally heated cavity or a wide range of thermal gradients and cool down rates. A monitoring system compatible with the rocket telemetry provides furnace performance and sample growth rate data throughout the processing cycle.

  11. Weldability Characteristics of Sintered Hot-Forged AISI 4135 Steel Produced through P/M Route by Using Pulsed Current Gas Tungsten Arc Welding

    NASA Astrophysics Data System (ADS)

    Joseph, Joby; Muthukumaran, S.; Pandey, K. S.

    2016-01-01

    Present investigation is an attempt to study the weldability characteristics of sintered hot-forged plates of AISI 4135 steel produced through powder metallurgy (P/M) route using matching filler materials of ER80S B2. Compacts of homogeneously blended elemental powders corresponding to the above steel were prepared on a universal testing machine (UTM) by taking pre-weighed powder blend with a suitable die, punch and bottom insert assembly. Indigenously developed ceramic coating was applied on the entire surface of the compacts in order to protect them from oxidation during sintering. Sintered preforms were hot forged to flat, approximately rectangular plates, welded by pulsed current gas tungsten arc welding (PCGTAW) processes with aforementioned filler materials. Microstructural, tensile and hardness evaluations revealed that PCGTAW process with low heat input could produce weldments of good quality with almost nil defects. It was established that PCGTAW joints possess improved tensile properties compared to the base metal and it was mainly attributed to lower heat input, resulting in finer fusion zone grains and higher fusion zone hardness. Thus, the present investigation opens a new and demanding field in research.

  12. Improvement of Mechanical Properties of Spheroidized 1045 Steel by Induction Heat Treatment

    NASA Astrophysics Data System (ADS)

    Kim, Minwook; Shin, Jung-Ho; Choi, Young; Lee, Seok-Jae

    2016-04-01

    The effects of induction heat treatment on the formation of carbide particles and mechanical properties of spheroidized 1045 steel were investigated by means of microstructural analysis and tensile testing. The induction spheroidization accelerated the formation of spherical cementite particles and effectively softened the steel. The volume fraction of cementite was found to be a key factor that affected the mechanical properties of spheroidized steels. Further tests showed that sequential spheroidization by induction and furnace heat treatments enhanced elongation within a short spheroidization time, resulting in better mechanical properties. This was due to the higher volume fraction of spherical cementite particles that had less diffusion time for particle coarsening.

  13. Arcing time analysis of liquid nitrogen with respect to electrode materials

    NASA Astrophysics Data System (ADS)

    Junaid, Muhammad; Yang, Kun; Ge, Hanming; Wang, Jianhua

    2018-03-01

    Unlike sulphur hexafluoride (SF6), liquid nitrogen (LN2) is cost effective, environment friendly and cryogenic dielectric. It has astounding insulating properties with the potential to decrease power loss in switchgear applications due to its remarkably low temperatures. The basic research is however a necessity to observe the performance of LN2 subjected to high luminance arcs. So far, there are no findings that refer to the arcing time inside the LN2 environment. The objective of this work was to investigate the arcing times in LN2 and compare the results with open air conditions using different electrode materials. Experiments were conducted on different DC voltages and their arcing times were measured. Three different kinds of electrode materials, namely: pure copper (Cu), stainless used steel (SUS) and aluminium alloy (Al 6061) were tested under 1 atmospheric pressure. The results revealed that LN2 extinguishes arc in almost half the amount of time required by the open air insulation. With Al 6061 has the shortest arcing time, whilst Cu, the second best choice and SUS places last in the evaluation. It was encapsulated from the findings that LN2 is a better choice than air insulation in terms of arc quenching and a better alternative to SF6 when environment is the priority.

  14. Gas Metal Arc Welding Parameters Effect on Properties of Tailored Orbital Weld of SS304 and BS1387

    NASA Astrophysics Data System (ADS)

    Ayof, M. N.; Hussein, N. I. S.; Noh, M. Z. Mohd

    2017-09-01

    Dissimilar material pipes in a power plant boiler water piping system are used to transmit water at various temperatures, either in extremely high temperature water or room temperature water. In this study, tailored orbital welding of dissimilar material of Stainless Steel (SS) 304 and British Steel (BS) 1387 were performed by Gas Metal Arc Welding (GMAW) with automated fixed nozzle-rotational jig. This study focused on GMAW parameters variation effects on mechanical properties of SS304 and BS1387 dissimilar material tailored orbital welding. The weldment quality was tested by performing non-destructive dye penetrant test. The tensile strength and microhardness were studied to verify the influence of welding parameters variations. Design of Experiment (DOE) was employed to generate process parameter using Response Surface Methodology (RSM) method. Welding parameters that were arc current, arc voltage and travel speed as input response, whilst, tensile strength and microhardness as output response. Results from non-destructive test showed no major defect occurred. The tensile strength and microhardness increased when arc current and voltage increased and travel speed decreased. Microhardness at weldment was higher than base material.

  15. Research, Development, and Field Testing of Thermochemical Recuperation for High Temperature Furnace

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurek, Harry; Kozlov, Aleksandr

    Gas Technology Institute (GTI) evaluated the technical and economic feasibility of utilizing a non-catalytic ThermoChemical Recuperation System (TCRS) to recover a significant amount of energy from the waste gases of natural gas fired steel reheat furnaces. The project was related to DOE-AMO’s (formerly known as ITP) one of the technical areas of interest: Technologies to improve energy efficiency and reduce the carbon footprint of equipment currently used in energy-intensive industries such as iron and steel, and reduce by at least 30% energy consumption and carbon dioxide emission compared to the conventional technologies. ThermoChemical Recuperation (TCR) is a technique that recoversmore » sensible heat in the exhaust gas from an industrial process, furnace, engine etc., when a hydrocarbon fuel is used for combustion. TCR enables waste heat recovery by both combustion air preheat and hydrocarbon fuel (natural gas, for example) reforming into a higher calorific fuel. The reforming process uses hot flue gas components (H2O and CO2) or steam to convert the fuel into a combustible mixture of hydrogen (H2), carbon monoxide (CO), and some unreformed hydrocarbons (CnHm). Reforming of natural gas with recycled exhaust gas or steam can significantly reduce fuel consumption, CO2 emissions and cost as well as increase process thermal efficiency. The calorific content of the fuel can be increased by up to ~28% with the TCR process if the original source fuel is natural gas. In addition, the fuel is preheated during the TCR process adding sensible heat to the fuel. The Research and Development work by GTI was proposed to be carried out in three Phases (Project Objectives). • Phase I: Develop a feasibility study consisting of a benefits-derived economic evaluation of a ThermoChemical Recuperation (TCR) concept with respect to high temperature reheat furnace applications within the steel industry (and cross-cutting industries). This will establish the design parameters

  16. On Improving the Quality of Gas Tungsten Arc Welded 18Ni 250 Maraging Steel Rocket Motor Casings

    NASA Astrophysics Data System (ADS)

    Gupta, Renu N.; Raja, V. S.; Mukherjee, M. K.; Narayana Murty, S. V. S.

    2017-10-01

    In view of their excellent combination of strength and toughness, maraging steels (18Ni 250 grade) are widely used for the fabrication of large sized solid rocket motor casings. Gas tungsten arc welding is commonly employed to fabricate these thin walled metallic casings, as the technique is not only simple but also provides the desired mechanical properties. However, sometimes, radiographic examination of welds reveals typical unacceptable indications requiring weld repair. As a consequence, there is a significant drop in weld efficiency and productivity. In this work, the nature and the cause of the occurrence of these defects have been investigated and an attempt is made to overcome the problem. It has been found that weld has a tendency to form typical Ca and Al oxide inclusions leading to the observed defects. The use of calcium fluoride flux has been found to produce a defect free weld with visible effect on weld bead finish. The flux promotes the separation of inclusions, refines the grain size and leads to significant improvement in mechanical properties of the weldment.

  17. An improved gas extraction furnace

    NASA Technical Reports Server (NTRS)

    Wilkin, R. B.

    1972-01-01

    Design of glass furnace for analysis of rocks to determine nature and amount of trapped gas is described. Furnace heats specimen in vacuum conditions by radio frequency induction. Diagram of apparatus to show construction and operation is provided.

  18. Laser Welding of Coated Press-hardened Steel 22MnB5

    NASA Astrophysics Data System (ADS)

    Siltanen, Jukka; Minkkinen, Ari; Järn, Sanna

    The press-hardening process is widely used for steels that are used in the automotive industry. Using ultra-high-strength steels enables car manufacturers to build lighter, stronger, and safer vehicles at a reduced cost and generating lower CO2 emissions. In the study, laser welding properties of the coated hot stamped steel 22BMn5 were studied. A constant 900 °C temperature was used to heat the steel plates, and two different furnace times were used in the press-hardening, being 300 and 740 seconds. Some of the plates were shot blasted to see the influence of the partly removed oxide layer on the laser welding and quality. The welding set-up, welding, and testing of the weld specimens complied with the automotive testing code SEP 1220.

  19. Wetting of single crystal mullite by borosilicate and yttrium-aluminosilicate glasses and wetting phenomena of steels containing aluminum and titanium

    NASA Astrophysics Data System (ADS)

    Eldred, Benjamin Todd

    This dissertation consists of two major sections. The first section concerns the wetting of single crystal mullite by borosilicate and yttrium-aluminosilicate glasses. The borosilicate glass showed poor wetting and interacted only moderately with the substrate. The yttrium-aluminosilicate glass interacted strongly with mullite and showed very good wetting. Balanced chemical equations between each glass and mullite were derived from EDS data. Wetting was found to be dependent on the crystallographic orientation of the substrate, in agreement with previous studies of the surface energy of mullite. The second section concerns the wetting phenomena of steels containing aluminum and titanium. A modified sessile drop technique was used to investigate the wetting of steels containing aluminum and/or titanium as a function of furnace atmosphere. It was found that the steel chemistry and furnace atmosphere had little effect on wetting except in the case of a particular ultra-low carbon steel containing both aluminum and titanium. This steel was found to show significantly lower contact angles than any other steel tested when it was in an atmosphere of pure hydrogen. As nitrogen was added to the atmosphere, the contact angle increased monotonically and irreversibly. The interaction between aluminum, titanium, and nitrogen is explained in terms of first-order interaction coefficients available in thermodynamic literature.

  20. Challenges in Melt Furnace Tests

    NASA Astrophysics Data System (ADS)

    Belt, Cynthia

    2014-09-01

    Measurement is a critical part of running a cast house. Key performance indicators such as energy intensity, production (or melt rate), downtime (or OEE), and melt loss must all be understood and monitored on a weekly or monthly basis. Continuous process variables such as bath temperature, flue temperature, and furnace pressure should be used to control the furnace systems along with storing the values in databases for later analysis. While using measurement to track furnace performance over time is important, there is also a time and place for short-term tests.

  1. Assessing dust exposure in an integrated iron and steel manufacturing plant in South India.

    PubMed

    Ravichandran, B; Krishnamurthy, V; Ravibabu, K; Raghavan, S; Rajan, B K; Rajmohan, H R

    2008-01-01

    A study to monitor and estimate respirable particulate matter (RPM), toxic trace metal concentrations in the work environment was carried out in different sections of an integrated steel manufacturing industry. The average RPM concentration observed varied according to the section blast furnace was 2.41 mg/m;{3}; energy optimization furnace, 1.87 mg/m;{3}; sintering plant, 0.98 mg/m;{3}; continuous casting machine, 1.93 mg/m;{3}. The average trace metal concentration estimated from the RPM samples like iron, manganese, lead and chromium did not exceed ACGIH prescribed levels.

  2. Toxic-Waste Disposal by Drain-in-Furnace Technique

    NASA Technical Reports Server (NTRS)

    Compton, L. E.; Stephens, J. B.; Moynihan, P. I.; Houseman, J.; Kalvinskas, J. J.

    1986-01-01

    Compact furnace moved from site to site. Toxic industrial waste destroyed using furnace concept developed for disposal of toxic munitions. Toxic waste drained into furnace where incinerated immediately. In furnace toxic agent rapidly drained and destroyed in small combustion chamber between upper and lower layers of hot ceramic balls

  3. 40 CFR 63.1652 - Emission standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be discharged into the atmosphere from any new or reconstructed submerged arc furnace exhaust gases...) Existing open submerged arc furnaces. No owner or operator shall cause to be discharged into the atmosphere... discharged into the atmosphere from any existing semi-sealed submerged arc furnace exhaust gases (including...

  4. Refractory of Furnaces to Reduce Environmental Impact

    NASA Astrophysics Data System (ADS)

    Hanzawa, Shigeru

    2011-10-01

    The energy load of furnaces used in the manufacturing process of ceramics is quite large. Most of the environmental impact of ceramics manufacturing is due to the CO2 produced from this high energy load. To improve this situation, R&D has focused on furnace systems and techniques of control in order to reduce energy load. Since furnaces are comprised of refractory, consideration of their mechanical and thermal characteristics is important. Herein are described several refractory types which were chosen through comparison of the characteristics which contribute to heat capacity reduction, heat insulating reinforcement and high emissivity, thereby improving thermal radiation heat transfer efficiency to the ceramic articles. One selected refractory material which will reduce the environmental impact of a furnace, chosen considering low heat capacity and high emissivity characteristics, is SiC. In this study, thermal radiation heat transfer efficiency improvement and its effect on ceramic articles in the furnace and oxidation behaviour were investigated at 1700K. A high density SiC refractory, built into the furnace at construction, has relatively high oxidation durability and has the ability to reduce environmental impact-CO2 by 10 percent by decreasing the furnace's energy load. However, new oxidation prevention techniques for SiC will be necessary for long-term use in industrial furnaces, because passive to active oxidation transition behaviour of commercial SiC refractory is coming to close ideal.

  5. Study of the welding gas influence on a controlled short-arc GMAW process by optical emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Wilhelm, G.; Gött, G.; Schöpp, H.; Uhrlandt, D.

    2010-11-01

    The controlled short-arc processes, variants of the gas metal arc welding (GMAW) process, which have recently been developed, are used to reduce the heat input into the workpiece. Such a process with a wire feeding speed which varies periodically, using a steel wire and a steel workpiece to produce bead-on-plate welds has been investigated. As welding gases CO2 and a mixture of Ar and O2 have been used. Depending on the gas, the properties of the plasma change, and as a consequence the weldseams themselves also differ distinctly. Optical emission spectroscopy has been applied to analyse the plasma. The radial profiles of the emission coefficients of an iron line and an argon line or an atomic oxygen line, respectively, have been determined. These profiles indicate the establishment of a metal vapour arc core which has a broader profile under CO2 but is more focused in the centre for argon. The measured iron line emission was near to its norm maximum in the case of CO2. From this fact, temperatures around 8000 K and a metal vapour molar fraction above 75% in the arc centre could be roughly estimated for this case. Estimations of the electrical conductivity and the arc field indicate that the current path must include not only the metal vapour arc core but also outer hot regions dominated by welding gas properties in the case of argon.

  6. Design and Construction of a Small Vacuum Furnace

    NASA Astrophysics Data System (ADS)

    Peawbang, P.; Thedsakhulwong, A.

    2017-09-01

    The purpose of this research is designed and constructed of a small vacuum furnace. A cylindrical graphite was chosen as the material of the furnace, the cylinder aluminium and copper sheets were employed to prevent the heat radiation that transfers from the furnace to the chamber wall. A rotary pump used, the pressure of graphite furnace can be pumped up to 30 mTorr and heated up to 700 °C driving by wire and the temperature of the chamber wall is relatively remained too low. In addition, heat loss obtained from the graphite furnace by conduction, convection, and radiation were analyzed. The dominating heat loss was found to be caused by the blackbody radiation, which can thus be used to estimate the relationship between graphite furnace temperature and the drive power needed. The cylindrical graphite furnace has an inner diameter of 44 mm, the outer diameter of 60 mm and 45 mm in height, the 355.5 W of power is needed to drive the furnace to 700 °C.

  7. Molten metal holder furnace and casting system incorporating the molten metal holder furnace

    DOEpatents

    Kinosz, Michael J.; Meyer, Thomas N.

    2003-02-11

    A bottom heated holder furnace (12) for containing a supply of molten metal includes a storage vessel (30) having sidewalls (32) and a bottom wall (34) defining a molten metal receiving chamber (36). A furnace insulating layer (42) lines the molten metal receiving chamber (36). A thermally conductive heat exchanger block (54) is located at the bottom of the molten metal receiving chamber (36) for heating the supply of molten metal. The heat exchanger block (54) includes a bottom face (65), side faces (66), and a top face (67). The heat exchanger block (54) includes a plurality of electrical heaters (70) extending therein and projecting outward from at least one of the faces of the heat exchanger block (54), and further extending through the furnace insulating layer (42) and one of the sidewalls (32) of the storage vessel (30) for connection to a source of electrical power. A sealing layer (50) covers the bottom face (65) and side faces (66) of the heat exchanger block (54) such that the heat exchanger block (54) is substantially separated from contact with the furnace insulating layer (42).

  8. Solar Convective Furnace for Metals Processing

    NASA Astrophysics Data System (ADS)

    Patidar, Deepesh; Tiwari, Sheetanshu; Sharma, Piyush; Pardeshi, Ravindra; Chandra, Laltu; Shekhar, Rajiv

    2015-11-01

    Metals processing operations, primarily soaking, heat treatment, and melting of metals are energy-intensive processes using fossil fuels, either directly or indirectly as electricity, to operate furnaces at high temperatures. Use of concentrated solar energy as a source of heat could be a viable "green" option for industrial heat treatment furnaces. This paper introduces the concept of a solar convective furnace which utilizes hot air generated by an open volumetric air receiver (OVAR)-based solar tower technology. The potential for heating air above 1000°C exists. Air temperatures of 700°C have already been achieved in a 1.5-MWe volumetric air receiver demonstration plant. Efforts to retrofit an industrial aluminium soaking furnace for integration with a solar tower system are briefly described. The design and performance of an OVAR has been discussed. A strategy for designing a 1/15th-scale model of an industrial aluminium soaking furnace has been presented. Preliminary flow and thermal simulation results suggest the presence of recirculating flow in existing furnaces that could possibly result in non-uniform heating of the slabs. The multifarious uses of concentrated solar energy, for example in smelting, metals processing, and even fuel production, should enable it to overcome its cost disadvantage with respect to solar photovoltaics.

  9. Design and Development of Tilting Rotary Furnace

    NASA Astrophysics Data System (ADS)

    Sai Varun, V.; Tejesh, P.; Prashanth, B. N.

    2018-02-01

    Casting is the best and effective technique used for manufacturing products. The important accessory for casting is furnace. Furnace is used to melt the metal. A perfect furnace is one that reduces the wastage of material, reduces the cost of manufacturing and there by reduces the cost of production. Of all the present day furnaces there may be wastage of material, and the chances of increasing the time of manufacturing as the is continuous need of tilting of the furnace for every mould and then changing the moulds. Considering these aspects, a simple and least expensive tilting rotary furnace is designed and developed. The Tilting and Rotary Furnace consists of mainly melting chamber and the base. The metal enters the melting chamber through the input door that is provided on the top of the melting chamber. Inside the melting chamber there is a graphite furnace. The metal is melted in the graphite crucible. An insulation of ceramic fibre cloth is provided inside the furnace. The metal is melted using Propane gas. The propane gas is easily available and economic. The gas is burned using a pilot burner. The pilot burner is more efficient that other burners. The pilot burner is lit with a push button igniter. The pilot burner is located at the bottom of the combustion chamber. This enables the uniform heating of the metal inside the crucible. The temperature inside the melting chamber is noted using a temperature sensor. The gas input is cut-off if the temperature is exceeding a specific temperature. After the melting of the metal is done the furnace is tilted and after the mould is filled it is rotated. The external gears are used to controlling the tilting. The results of studies carried out for the design & development of low cost, simple furnace that can be mounted anywhere on the shop floor and this can be very much useful for the education purposes and small scale manufacturing. The furnace can be rotated in 360 degrees and can help in reducing the time taken

  10. Crystal growth and furnace analysis

    NASA Technical Reports Server (NTRS)

    Dakhoul, Youssef M.

    1986-01-01

    A thermal analysis of Hg/Cd/Te solidification in a Bridgman cell is made using Continuum's VAST code. The energy equation is solved in an axisymmetric, quasi-steady domain for both the molten and solid alloy regions. Alloy composition is calculated by a simplified one-dimensional model to estimate its effect on melt thermal conductivity and, consequently, on the temperature field within the cell. Solidification is assumed to occur at a fixed temperature of 979 K. Simplified boundary conditions are included to model both the radiant and conductive heat exchange between the furnace walls and the alloy. Calculations are performed to show how the steady-state isotherms are affected by: the hot and cold furnace temperatures, boundary condition parameters, and the growth rate which affects the calculated alloy's composition. The Advanced Automatic Directional Solidification Furnace (AADSF), developed by NASA, is also thermally analyzed using the CINDA code. The objective is to determine the performance and the overall power requirements for different furnace designs.

  11. Arc Voltage Between Deion Grid Affected by Division of Arc in Magnetic Driven Arc

    NASA Astrophysics Data System (ADS)

    Inuzuka, Yutaro; Yamato, Takashi; Yamamoto, Shinji; Iwao, Toru

    2016-10-01

    Magnetic driven arc has been applied to DC breaker and fault current limiters. However, it has not been researched, especially stagnation and re-strike of the arc. In this paper, the arc voltage between deion grid affected by division of arc in magnetic driven arc and arc behavior are measured by using the oscilloscope and HSVC (High Speed Video Camera). As a result, arc voltage increased because of division of the arc. The arc mean moving speed increases with increasing the external magnetic field. However, when the arc was not stalemate, the arc moving speed does not change so much. The arc re-strike time increases and stalemate time decreases with increasing the external magnetic field. Therefore, the anode spot moving speed increases 8 times because arc re-strike occurs easily with the external magnetic field. Thus, the erosion of electrodes decreases and the arc movement becomes the smooth. When the arc is divided, the arc voltage increased because of the electrode fall voltage. Therefore, the arc voltage increases with increasing the number of deion grid.

  12. Bond characteristics of reinforcing steel embedded in geopolymer concrete

    NASA Astrophysics Data System (ADS)

    Kathirvel, Parthiban; Thangavelu, Manju; Gopalan, Rashmi; Raja Mohan Kaliyaperumal, Saravana

    2017-07-01

    The force transferring between reinforcing steel and the surrounding concrete in reinforced concrete is influenced by several factors. Whereas, the study on bond behaviour of geopolymer concrete (GPC) is lagging. In this paper, an experimental attempt has been made to evaluate the geopolymer concrete bond with reinforcing steel of different diameter and embedded length using standard pull out test. The geopolymer concrete is made of ground granulated blast furnace slag (GGBFS) as geopolymer source material (GSM). The tests were conducted to evaluate the development of bond between steel and concrete of grade M40 and M50 with 12 and 16 mm diameter reinforcing steel for geopolymer and cement concrete mixes and to develop a relation between bond strength and compressive strength. From the experimental results, it has been observed that the bond strength of the geopolymer concrete mixes was more compared to the cement concrete mixes and increases with the reduction in the diameter of the bar.

  13. ZrN coatings deposited by high power impulse magnetron sputtering and cathodic arc techniques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Purandare, Yashodhan, E-mail: Y.Purandare@shu.ac.uk; Ehiasarian, Arutiun; Hovsepian, Papken

    Zirconium nitride (ZrN) coatings were deposited on 1 μm finish high speed steel and 316L stainless steel test coupons. Cathodic Arc (CA) and High Power Impulse Magnetron Sputtering (HIPIMS) + Unbalanced Magnetron Sputtering (UBM) techniques were utilized to deposit coatings. CA plasmas are known to be rich in metal and gas ions of the depositing species as well as macroparticles (droplets) emitted from the arc sports. Combining HIPIMS technique with UBM in the same deposition process facilitated increased ion bombardment on the depositing species during coating growth maintaining high deposition rate. Prior to coating deposition, substrates were pretreated with Zr{sup +}more » rich plasma, for both arc deposited and HIPIMS deposited coatings, which led to a very high scratch adhesion value (L{sub C2}) of 100 N. Characterization results revealed the overall thickness of the coatings in the range of 2.5 μm with hardness in the range of 30–40 GPa depending on the deposition technique. Cross-sectional transmission electron microscopy and tribological experiments such as dry sliding wear tests and corrosion studies have been utilized to study the effects of ion bombardment on the structure and properties of these coatings. In all the cases, HIPIMS assisted UBM deposited coating fared equal or better than the arc deposited coatings, the reasons being discussed in this paper. Thus H+U coatings provide a good alternative to arc deposited where smooth, dense coatings are required and macrodroplets cannot be tolerated.« less

  14. AN INSTRUMENT TO MEASURE THE ELECTRICAL CONDUCTIVITY OF ARC PLASMA JETS

    DTIC Science & Technology

    The instrument was calibrated by moving aluminum or graphite rods through the transducer. By using thin-wall, stainless steel tubing, the influence ... function for the transducer was also obtained. Tests were run on two different arc plasma jet facilities. Values of s, u ranged from 0.02 to 9 megamhos per second. (Author)

  15. Sealed rotary hearth furnace with central bearing support

    DOEpatents

    Docherty, James P.; Johnson, Beverly E.; Beri, Joseph

    1989-01-01

    The furnace has a hearth which rotates inside a stationary closed chamber and is supported therein on vertical cylindrical conduit which extends through the furnace floor and is supported by a single center bearing. The charge is deposited through the furnace roof on the rim of the hearth as it rotates and is moved toward the center of the hearth by rabbles. Externally generated hot gases are introduced into the furnace chamber below the hearth and rise through perforations in the hearth and up through the charge. Exhaust gases are withdrawn through the furnace roof. Treated charge drops from a center outlet on the hearth into the vertical cylindrical conduit which extends downwardly through the furnace floor to which it is also sealed.

  16. Crystal growth furnace with trap doors

    DOEpatents

    Sachs, Emanual M.; Mackintosh, Brian H.

    1982-06-15

    An improved furnace is provided for growing crystalline bodies from a melt. The improved furnace is characterized by a door assembly which is remotely controlled and is arranged so as to selectively shut off or permit communication between an access port in the furnace enclosure and a hot zone within that enclosure. The invention is especially adapted to facilitate use of crystal growing cartridges of the type disclosed in U.S. Pat. No. 4,118,197.

  17. Crystal growth furnace with trap doors

    NASA Technical Reports Server (NTRS)

    Sachs, Emanual M. (Inventor); Mackintosh, Brian H. (Inventor)

    1982-01-01

    An improved furnace is provided for growing crystalline bodies from a melt. The improved furnace is characterized by a door assembly which is remotely controlled and is arranged so as to selectively shut off or permit communication between an access port in the furnace enclosure and a hot zone within that enclosure. The invention is especially adapted to facilitate use of crystal growing cartridges of the type disclosed in U.S. Pat. No. 4,118,197.

  18. Thermal Insulation of Wet Shielded Metal Arc Welds

    DTIC Science & Technology

    1993-06-01

    not as versatile as dry underwater welding with respect to the variety of processes that can be performed (i.e., GMAW, GTAW , SMAW). However, since...deposition rate processes are required for underwater welding. Therefore, even in enclosures where GMAW and GTAW could be used, SMAW is the most frequently...welding steel in a dry environment: GMAW. GTAW , SMAW and submerged arc welding. Because of their relatively low metal deposition rates for manual

  19. Programmable multi-zone furnace for microgravity research

    NASA Technical Reports Server (NTRS)

    Rosenthal, Bruce N.; Krolikowski, Cathryn R.

    1991-01-01

    In order to provide new furnace technology to accommodate microgravity research studies and commercial applications in material processes, research has been initiated on the development of the Programmable-Multi-zone Furnace (PMZF). The PMZF is described as a multi-user materials processing furnace facility that is composed of thirty or more heater elements in series on a muffle tube or in a stacked ring-type configuration and independently controlled by a computer. One of the aims of the PMZF project is to allow furnace thermal gradient profiles to be reconfigured without physical modification of the hardware by creating the capability of reconfiguring thermal profiles in response to investigators' requests. The future location of the PMZF facility is discussed; the preliminary science survey results and preliminary conceptual designs for the PMZF are presented; and a review of multi-zone furnace technology is given.

  20. Control of Gas Tungsten Arc welding pool shape by trace element addition to the weld pool

    DOEpatents

    Heiple, C.R.; Burgardt, P.

    1984-03-13

    An improved process for Gas Tungsten Arc welding maximizes the depth/width ratio of the weld pool by adding a sufficient amount of a surface active element to insure inward fluid flow, resulting in deep, narrow welds. The process is especially useful to eliminate variable weld penetration and shape in GTA welding of steels and stainless steels, particularly by using a sulfur-doped weld wire in a cold wire feed technique.

  1. Effect of Basicity on Basic Oxygen Furnace (BOF) Slag Solidification Microstructure and Mineralogy

    NASA Astrophysics Data System (ADS)

    Liu, Chunwei; Guo, Muxing; Pandelaers, Lieven; Blanpain, Bart; Huang, Shuigen

    Slag valorization in added value construction applications can contribute substantially to the sustainability of steel industry. The present work aims to investigate the crystallization behavior of a typical industrial Basic Oxygen Furnace (BOF) slag (CaO-FeOx-SiO2-based slag) by varying the basicity through hot stage engineering. A sample of industry Basic Oxygen Slag (BOF) was mixed with different quantities of silica (SiO2) to modify basicity. The effect of basicity on solidification microstructure and mineralogy was studied. The results suggest that the mineralogy of the solidified slag can be manipulated to enhance its suitability as raw material for construction applications.

  2. Optical cavity furnace for semiconductor wafer processing

    DOEpatents

    Sopori, Bhushan L.

    2014-08-05

    An optical cavity furnace 10 having multiple optical energy sources 12 associated with an optical cavity 18 of the furnace. The multiple optical energy sources 12 may be lamps or other devices suitable for producing an appropriate level of optical energy. The optical cavity furnace 10 may also include one or more reflectors 14 and one or more walls 16 associated with the optical energy sources 12 such that the reflectors 14 and walls 16 define the optical cavity 18. The walls 16 may have any desired configuration or shape to enhance operation of the furnace as an optical cavity 18. The optical energy sources 12 may be positioned at any location with respect to the reflectors 14 and walls defining the optical cavity. The optical cavity furnace 10 may further include a semiconductor wafer transport system 22 for transporting one or more semiconductor wafers 20 through the optical cavity.

  3. Novel Approach for Welding Stainless Steel Using Cr-Free Welding Consumables

    DTIC Science & Technology

    2004-12-31

    Breakdown potential ERP Repassivation potential SS Stainless steel SMAW Shielded metal arc welding GTAW Gas tungsten arc welding PEL Permissible...0.1 M NaCl. 14 4. List of Tables Table 1. Details of GTAW procedure. 7 1 5. Acknowledgements The work in this report was...resistance, filler metals matching or exceeding the chromium (Cr) content of the base metal must be used. The Cr content of Types 304 and 308 stainless

  4. Thermal regulation in multiple-source arc welding involving material transformations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doumanidis, C.C.

    1995-06-01

    This article addresses regulation of the thermal field generated during arc welding, as the cause of solidification, heat-affected zone and cooling rate related metallurgical transformations affecting the final microstructure and mechanical properties of various welded materials. This temperature field is described by a dynamic real-time process model, consisting of an analytical composite conduction expression for the solid region, and a lumped-state, double-stream circulation model in the weld pool, integrated with a Gaussian heat input and calibrated experimentally through butt joint GMAW tests on plain steel plates. This model serves as the basis of an in-process thermal control system employing feedbackmore » of part surface temperatures measured by infrared pyrometry; and real-time identification of the model parameters with a multivariable adaptive control strategy. Multiple heat inputs and continuous power distributions are implemented by a single time-multiplexed torch, scanning the weld surface to ensure independent, decoupled control of several thermal characteristics. Their regulation is experimentally obtained in longitudinal GTAW of stainless steel pipes, despite the presence of several geometrical, thermal and process condition disturbances of arc welding.« less

  5. Cavitation erosion resistance of diamond-like carbon coating on stainless steel

    NASA Astrophysics Data System (ADS)

    Cheng, Feng; Jiang, Shuyun

    2014-02-01

    Two diamond-like carbon (DLC) coatings are prepared on stainless steel 304 by cathodic arc plasma deposition technology at different substrate bias voltages and arc currents (-200 V/80 A, labeled DLC-1, and -100 V/60 A, labeled DLC-2). Cavitation tests are performed by using a rotating-disk test rig to explore the cavitation erosion resistance of the DLC coating. The mass losses, surface morphologies, chemical compositions and the phase constituents of the specimens after cavitation tests are examined by using digital balance, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The results indicate that the DLC-2 coatings can elongate the incubation period of stainless steel, leading to an excellent cavitation erosion resistance as compared to the untreated stainless steel specimens. After duration of 100 h cavitation test, serious damaged surfaces and plenty of scratches can be observed on the surfaces of the stainless steel specimens, while only a few grooves and tiny pits are observed on the DLC-2 coatings. It is concluded that, decreasing micro defects and increasing adhesion can reduce the delamination of DLC coating, and the erosion continues in the stainless steel substrate after DLC coating failure, and the eroded surface of the substrate is subjected to the combined action from cavitation erosion and slurry erosion.

  6. A high-temperature furnace for applications in microgravity

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Technology in the area of material processing and crystal growth has been greatly furthered by research in microgravity environments. The role of efficient, lightweight furnaces with reliable performance is crucial in these experiments. A need exists for the development of a readily duplicated, high-temperature furnace satisfying stringent weight, volume, and power constraints. A furnace was designed and is referred to as the UAH SHIELD. Stringent physical and operating characteristics for the system were specified, including a maximum weight of 20 kg, a maximum power requirement of 60 W, and a volume of the furnace assembly, excluding the batteries, limited to half a Get-Away-Special canister. The UAH SHIELD furnace uses radiation shield and vacuum technology applied in the form of a series of concentric cylinders enclosed on either end with disks. Thermal testing of a furnace prototype was performed in addition to some thermal and structural analysis. Results indicate the need for spacing of the shields to accommodate the thermal expansion during furnace operation. In addition, a power dissipation of approximately 100 W and system weight of approximately 30 kg was found for the current design.

  7. A preliminary ferritic-martensitic stainless steel constitution diagram

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balmforth, M.C.; Lippold, J.C.

    1998-01-01

    This paper describes preliminary research to develop a constitution diagram that will more accurately predict the microstructure of ferritic and martensitic stainless steel weld deposits. A button melting technique was used to produce a wide range of compositions using mixtures of conventional ferritic and martensitic stainless steels, including types 403, 409, 410, 430, 439 and 444. These samples were prepared metallographically, and the vol-% ferrite and martensite was determined quantitatively. In addition, the hardness and ferrite number (FN) were measured. Using this data, a preliminary constitution diagram is proposed that provides a more accurate method for predicting the microstructures ofmore » arc welds in ferritic and martensitic stainless steels.« less

  8. Some considerations for a method that simultaneously measures the temperature and emissivity of a metal in a high temperature furnace

    NASA Astrophysics Data System (ADS)

    Iuchi, Tohru; Furukawa, Tohru

    2004-12-01

    This article describes some considerations for designing a practical radiation thermometry system for a glossy metal moving through a high temperature furnace, such as a continuous annealing furnace. In order to accomplish this task, two problems must be solved. The emissivity compensation of an object must be calculated and the furnace's background radiation noise must be eliminated. The authors have proposed a method that uses the radiance's polarized directional properties to simultaneously measure the emissivity and temperature to solve the first problem and a technique using a pseudo-blackbody installed in the furnace to solve the second problem. During heating, there is a one-to-one correspondence between the emissivity and the ratio of p- and s-polarized radiances for metals. This characteristic has successfully led to the development of a method for simultaneously measuring the emissivity and temperature of metals regardless of a potential large change in emissivity. Introducing a pseudo-blackbody radiator into a furnace removes the background radiation noise. Moreover, the blackbody radiator supplies a constant reference radiance. This reference plays an important role in maintaining the principle of emissivity-compensated radiation thermometry inside the furnace. Experimental results have simultaneously measured the emissivity and temperature of stainless steel at 1300 K with errors of 12% and 0.96%, respectively. These values were attained even though the s-polarized emissivities change from 0.25 to 0.75 at a wavelength of 0.9 μm. These errors can be achieved by designing the apparatus to have a solid angle, the aperture of the pseudo-blackbody subtended by a measuring point of the specimen, of more than 0.02π steradians. The accuracy of this method is heavily dependent upon the specimen's surface roughness. The maximum surface roughness that allows for the successful utilization of this method is Ra=0.12 μm.

  9. Spatial structure of the arc in a pulsed GMAW process

    NASA Astrophysics Data System (ADS)

    Kozakov, R.; Gött, G.; Schöpp, H.; Uhrlandt, D.; Schnick, M.; Häßler, M.; Füssel, U.; Rose, S.

    2013-06-01

    A pulsed gas metal arc welding (GMAW) process of steel under argon shielding gas in the globular mode is investigated by measurements and simulation. The analysis is focussed on the spatial structure of the arc during the current pulse. Therefore, the radial profiles of the temperature, the metal vapour species and the electric conductivity are determined at different heights above the workpiece by optical emission spectroscopy (OES). It is shown that under the presence of metal vapour the temperature minimum occurs at the centre of the arc. This minimum is preserved at different axial positions up to 1 mm above the workpiece. In addition, estimations of the electric field in the arc from the measurements are given. All these results are compared with magneto-hydrodynamic simulations which include the evaporation of the wire material and the change of the plasma properties due to the metal vapour admixture in particular. The experimental method and the simulation model are validated by means of the satisfactory correspondence between the results. Possible reasons for the remaining deviations and improvements of the methods which should be aspired are discussed.

  10. Development of refractories and related products for steel melting, finishing, and casting

    NASA Astrophysics Data System (ADS)

    Smirnov, A. N.

    2013-06-01

    The transformation of the consumption of refractories for the production, out-of-furnace treatment, and casting of steel is considered. The main trends in developing the refractory market are shown to be a significant decrease in the specific consumption of refractories per 1 t liquid steel and the predominant application of refractories based on magnesia raw materials and fused corundum for the working layers of melting units, ladles, and tundishes. The main trend in decreasing the specific costs of refractories is the development of refractories based on alternative sources of raw materials, which are cheaper and more available for refractory manufacturers.

  11. Energy efficiency technologies in cement and steel industry

    NASA Astrophysics Data System (ADS)

    Zanoli, Silvia Maria; Cocchioni, Francesco; Pepe, Crescenzo

    2018-02-01

    In this paper, Advanced Process Control strategies aimed at energy efficiency achievement and improvement in cement and steel industry are proposed. A flexible and smart control structure constituted by several functional modules and blocks has been developed. The designed control strategy is based on Model Predictive Control techniques, formulated on linear models. Two industrial control solutions have been developed, oriented to energy efficiency and process control improvement in cement industry clinker rotary kilns (clinker production phase) and in steel industry billets reheating furnaces. Tailored customization procedures for the design of ad hoc control systems have been executed, based on the specific needs and specifications of the analysed processes. The installation of the developed controllers on cement and steel plants produced significant benefits in terms of process control which resulted in working closer to the imposed operating limits. With respect to the previous control systems, based on local controllers and/or operators manual conduction, more profitable configurations of the crucial process variables have been provided.

  12. Use of natural radionuclides to determine the time range of the accidental melting of an orphan radioactive source in a steel recycling plant.

    PubMed

    Cantaluppi, Chiara; Ceccotto, Federica; Cianchi, Aldo

    2012-02-01

    In the rare event that an orphan radioactive source is melted in an Electric Arc Furnace steel recycling plant, the radionuclides present are partitioned in the different products, by-products and waste. As a consequence of an unforeseen melting of a radiocesium source, cesium radioisotopes can be found in the dust, together with many natural radionuclides from the decay of radon and thoron, which are present in the atmosphere, picked up from the off-gas evacuation system and associated with the dust of the air filtration system ("baghouse"). In this work we verified that the activity concentration of ²¹²Pb in this dust is essentially constant in a specific factory so that it is possible to use it to date back to the time of the accidental melting of the orphan radioactive source. The main features of this method are described below, together with the application to a particular case in which this method was used for dating the moment in which the dust was contaminated with ¹³⁷Cs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Analysis of various versions of the deoxidation of rail steel at OAO NTMK

    NASA Astrophysics Data System (ADS)

    Garber, A. K.; Arsenkin, A. M.; Grigorovich, K. V.; Shibaev, S. S.; Kushnarev, A. V.; Petrenko, Yu. P.

    2009-12-01

    The deoxidation of steel melted using various types of deoxidizers during out-of-furnace treatment is studied. The total oxygen and nitrogen content and the oxygen contents in the main types of oxide nonmetallic inclusions are determined by fractional gas analysis of steel samples taken from heats performed by various schedules. The main types of nonmetallic inclusions and their size distributions are found with qualitative and quantitative metallography. The oxygen content in the rail steel is minimal (5 ppm) when calcium carbide CaC2 is introduced into the metal in tapping of a converter. When the metal is deoxidized using a steel wire filled with calcium or a steel wire filled with silicocalcium, the oxygen content in rail steel is ≈8 and ≈11 ppm, respectively. A comparison of various processes of rail steel deoxidation under the OAO NTMK conditions shows that the limitation of the aluminum content (no more than 30 ppm) or the use of a wire with a calcium or calcium carbide filler is more effective than the use of a wire filled with silicocalcium.

  14. High-Flux Solar Furnace Facility | Concentrating Solar Power | NREL

    Science.gov Websites

    High-Flux Solar Furnace Facility High-Flux Solar Furnace Facility NREL's High-Flux Solar Furnace (HFSF) is a 10-kW optical furnace for testing high-temperature processes or applications requiring high range of technologies with a diverse set of experimental requirements. The high heating rates create the

  15. Water requirements of the iron and steel industry

    USGS Publications Warehouse

    Walling, Faulkner B.; Otts, Louis Ethelbert

    1967-01-01

    Twenty-nine steel plants surveyed during 1957 and 1958 withdrew from various sources about 1,400 billion gallons of water annually and produced 40.8 million tons of ingot steel. This is equivalent to about 34,000 gallons of water per ton of steel. Fifteen iron ore mines and fifteen ore concentration plants together withdrew annually about 89,000 million gallons to produce 15 million tons of iron ore concentrate, or 5,900 gallons per ton of concentrate. About 97 percent of the water used in the steel plants came from surface sources, 2.2 percent was reclaimed sewage, and 1.2 percent was ground water. Steel plants supplied about 96 percent of their own water requirements, although only three plants used self-supplied water exclusively. Water used by the iron ore mines and concentration plants was also predominantly self supplied from surface source. Water use in the iron and steel industry varied widely and depended on the availability of water, age and condition of plants and equipment, kinds of processes, and plant operating procedures. Gross water use in integrated steel plants ranged from 11,200 to 110,000 gallons per ton of steel ingots, and in steel processing plants it ranged from 4,180 to 26,700 gallons per ton. Water reuse also varied widely from 0 to 18 times in integrated steel plants and from 0 to 44 times in steel processing plants. Availability of water seemed to be the principal factor in determining the rate of reuse. Of the units within steel plants, a typical (median) blast furnace required 20,500 gallons of water per ton of pig iron. At the 1956-60 average rate of pig iron consumption, this amounts to about 13,000 gallons per ton of steel ingots or about 40 percent of that required by a typical integrated steel plant 33,200 gallons per ton. Different processes of iron ore concentration are devised specifically for the various kinds of ore. These processes result in a wide range of water use from 124 to 11,300 gallons of water per ton of iron ore

  16. Model of Draining of the Blast Furnace Hearth with an Impermeable Zone

    NASA Astrophysics Data System (ADS)

    Saxén, Henrik

    2015-02-01

    Due to demands of lower costs and higher productivity in the steel industry, the volume of operating blast furnaces has grown during the last decades. As the height is limited by the allowable pressure drop, the hearth diameter has grown considerably and, along with this, also draining-related problems. In this paper a mathematical model is developed for simulating the drainage in the case where an impermeable region exists in the blast furnace hearth. The model describes the quasi-stationary drainage process of a hearth with two operating tapholes, where the communication between the two pools of molten slag and iron can be controlled by parameterized expressions. The model also considers the case where the buoyancy of the liquids is sufficient for lifting the coke bed. The implications of different size of the liquid pools, communication between the pools, bed porosity, etc. are studied by simulation, and conclusions concerning their effect on the drainage behavior and evolution of the liquid levels in the hearth are drawn. The simulated liquid levels are finally demonstrated to give rise to a pressure profile acting on the hearth which agrees qualitatively with signals from strain gauges mounted in the hearth wall of an industrial ironmaking process.

  17. Effect of Different Cooling Rates on the Corrosion Behavior of High-Carbon Pearlitic Steel

    NASA Astrophysics Data System (ADS)

    Katiyar, Prvan Kumar; Misra, Sudhir; Mondal, K.

    2018-03-01

    The present work discusses the effect of pearlitic morphology on the corrosion behavior of high-carbon fully pearlitic steel in 3.5% NaCl solution. Four different types of pearlitic steels (furnace-cooled, as-received, air-cooled and forced-air-cooled) consisting of coarse, medium, fine and very fine microstructures, respectively, were tested. Electrochemical behavior of these steels was studied with the help of dynamic and linear polarization and AC impedance spectroscopic tests. The corrosion resistance improved with fineness of the microstructure in general. However, with further reduction in interlamellar spacing beyond a limit, the corrosion resistance reduced slightly. Formation of homogeneous distribution of microgalvanic cells between cementite and ferrite lamellae of fine pearlitic steel improved the corrosion resistance. However, entanglement of the lamellae of pearlite in very fine pearlitic structure as well as breaking of cementite lamellae due to finer pearlitic colonies was attributed to the higher corrosion of the forced-air-cooled steel as compared to the air-cooled steel.

  18. Discussion of Carbon Emissions for Charging Hot Metal in EAF Steelmaking Process

    NASA Astrophysics Data System (ADS)

    Yang, Ling-zhi; Jiang, Tao; Li, Guang-hui; Guo, Yu-feng

    2017-07-01

    As the cost of hot metal is reduced for iron ore prices are falling in the international market, more and more electric arc furnace (EAF) steelmaking enterprises use partial hot metal instead of scrap as raw materials to reduce costs and the power consumption. In this paper, carbon emissions based on 1,000 kg molten steel by charging hot metal in EAF steelmaking is studied. Based on the analysis of material and energy balance calculation in EAF, the results show that 146.9, 142.2, 137.0, and 130.8 kg/t of carbon emissions are produced at a hot metal ratio of 0 %, 30 %, 50 %, and 70 %, while 143.4, 98.5, 65.81, and 31.5 kg/t of carbon emissions are produced at a hot metal ratio of 0 %, 30 %, 50 %, and 70 % by using gas waste heat utilization (coal gas production) for EAF steelmaking unit process. However, carbon emissions are increased by charging hot metal for the whole blast furnace-electric arc furnace (BF-EAF) steelmaking process. In the condition that the hot metal produced by BF is surplus, as carbon monoxide in gas increased by charging hot metal, the way of coal gas production can be used for waste heat utilization, which reduces carbon emissions in EAF steelmaking unit process.

  19. Gas Metal Arc Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade Martensitic Steel

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Arakere, A.; Ramaswami, S.; Snipes, J. S.; Yavari, R.; Yen, C.-F.; Cheeseman, B. A.; Montgomery, J. S.

    2013-06-01

    A conventional gas metal arc welding (GMAW) butt-joining process has been modeled using a two-way fully coupled, transient, thermal-mechanical finite-element procedure. To achieve two-way thermal-mechanical coupling, the work of plastic deformation resulting from potentially high thermal stresses is allowed to be dissipated in the form of heat, and the mechanical material model of the workpiece and the weld is made temperature dependent. Heat losses from the deposited filler-metal are accounted for by considering conduction to the adjoining workpieces as well as natural convection and radiation to the surroundings. The newly constructed GMAW process model is then applied, in conjunction with the basic material physical-metallurgy, to a prototypical high-hardness armor martensitic steel (MIL A46100). The main outcome of this procedure is the prediction of the spatial distribution of various crystalline phases within the weld and the heat-affected zone regions, as a function of the GMAW process parameters. The newly developed GMAW process model is validated by comparing its predictions with available open-literature experimental and computational data.

  20. Nitride alloy layer formation of duplex stainless steel using nitriding process

    NASA Astrophysics Data System (ADS)

    Maleque, M. A.; Lailatul, P. H.; Fathaen, A. A.; Norinsan, K.; Haider, J.

    2018-01-01

    Duplex stainless steel (DSS) shows a good corrosion resistance as well as the mechanical properties. However, DSS performance decrease as it works under aggressive environment and at high temperature. At the mentioned environment, the DSS become susceptible to wear failure. Surface modification is the favourable technique to widen the application of duplex stainless steel and improve the wear resistance and its hardness properties. Therefore, the main aim of this work is to nitride alloy layer on the surface of duplex stainless steel by the nitriding process temperature of 400°C and 450°C at different time and ammonia composition using a horizontal tube furnace. The scanning electron microscopy and x-ray diffraction analyzer are used to analyse the morphology, composition and the nitrided alloy layer for treated DSS. The micro hardnesss Vickers tester was used to measure hardness on cross-sectional area of nitrided DSS. After nitriding, it was observed that the hardness performance increased until 1100 Hv0.5kgf compared to substrate material of 250 Hv0.5kgf. The thickness layer of nitride alloy also increased from 5μm until 100μm due to diffusion of nitrogen on the surface of DSS. The x-ray diffraction results showed that the nitride layer consists of iron nitride, expanded austenite and chromium nitride. It can be concluded that nitride alloy layer can be produced via nitriding process using tube furnace with significant improvement of microstructural and hardness properties.

  1. ArcS, the cognate sensor kinase in an atypical Arc system of Shewanella oneidensis MR-1.

    PubMed

    Lassak, Jürgen; Henche, Anna-Lena; Binnenkade, Lucas; Thormann, Kai M

    2010-05-01

    The availability of oxygen is a major environmental factor for many microbes, in particular for bacteria such as Shewanella species, which thrive in redox-stratified environments. One of the best-studied systems involved in mediating the response to changes in environmental oxygen levels is the Arc two-component system of Escherichia coli, consisting of the sensor kinase ArcB and the cognate response regulator ArcA. An ArcA ortholog was previously identified in Shewanella, and as in Escherichia coli, Shewanella ArcA is involved in regulating the response to shifts in oxygen levels. Here, we identified the hybrid sensor kinase SO_0577, now designated ArcS, as the previously elusive cognate sensor kinase of the Arc system in Shewanella oneidensis MR-1. Phenotypic mutant characterization, transcriptomic analysis, protein-protein interaction, and phosphotransfer studies revealed that the Shewanella Arc system consists of the sensor kinase ArcS, the single phosphotransfer domain protein HptA, and the response regulator ArcA. Phylogenetic analyses suggest that HptA might be a relict of ArcB. Conversely, ArcS is substantially different with respect to overall sequence homologies and domain organizations. Thus, we speculate that ArcS might have adopted the role of ArcB after a loss of the original sensor kinase, perhaps as a consequence of regulatory adaptation to a redox-stratified environment.

  2. Shielding Gas and Heat Input Effects on the Mechanical and Metallurgical Characterization of Gas Metal Arc Welding of Super Martensitic Stainless Steel (12Cr5Ni2Mo) Joints

    NASA Astrophysics Data System (ADS)

    Prabakaran, T.; Prabhakar, M.; Sathiya, P.

    This paper deals with the effects of shielding gas mixtures (100% CO2, 100% Ar and 80 % Ar + 20% CO2) and heat input (3.00, 3.65 and 4.33kJ/mm) on the mechanical and metallurgical characteristics of AISI 410S (American Iron and Steel Institute) super martensitic stainless steel (SMSS) by gas metal arc welding (GMAW) process. AISI 410S SMSS with 1.2mm diameter of a 410 filler wire was used in this study. A detailed microstructural analysis of the weld region as well as the mechanical properties (impact, microhardness and tensile tests at room temperature and 800∘C) was carried out. The tensile and impact fracture surfaces were further analyzed through scanning electron microscope (SEM). 100% Ar shielded welds have a higher amount of δ ferrite content and due to this fact the tensile strength of the joints is superior to the other two shielded welds.

  3. Crystal growth furnace safety system validation

    NASA Technical Reports Server (NTRS)

    Mackowski, D. W.; Hartfield, R.; Bhavnani, S. H.; Belcher, V. M.

    1994-01-01

    The findings are reported regarding the safe operation of the NASA crystal growth furnace (CGF) and potential methods for detecting containment failures of the furnace. The main conclusions are summarized by ampoule leak detection, cartridge leak detection, and detection of hazardous species in the experiment apparatus container (EAC).

  4. Evaluation of pitting corrosion resistance of high-alloyed stainless steels welds for FGD plants in Korea

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baek, K.K.; Sung, H.J.; Im, C.S.

    1998-12-31

    For successful application of high-alloyed stainless steels for Flue Gas Desulfurization (FGD) plants, pitting corrosion resistance of arc welds of N-added 6%Mo austenitic stainless steels (UNS N 08367) and super duplex stainless steels (UNS S 32550) made with various filler metals were evaluated using the Green Death solution. For Gas Tungsten Arc (GTA) and Gas Metal Arc (GMA) welds of N 08367, Critical Pitting Temperature (CPT) of base metal was 65--70 C, whereas weld made by ERNiCrMo-3 filler metal yielded CPT of 50 C. Welds made by ERNiCrMo-10 or ERNiCrMo-4 filler metals showed CPT of 60--65 C and 65--70C, respectively.more » For GTA and GMA welds of S 32550, CPT of welds made by ERNiCrMo-3 was 45--50 C, indicating that the filler metal can provide pitting corrosion resistance matching the S 32550 alloy. Thus, a proper pitting corrosion resistance of weldments of high-alloy stainless steels can be achieved by selecting filler metals having at least +10 higher Pitting Resistance Equivalent Number (PRE{sub N}) value than the base metal regardless of the type of arc welding process. The over-alloyed filler metals would compensate preferential segregation of Cr, MO along the dendrite boundary, which made the dendrite core more susceptible to pitting. Nitrogen addition to the GTA welds of N 08367 made with ERNiCrMo-3 failed to improve pitting corrosion resistance, which was attributed to the precipitation of nitrogen in the weld metal in the form of Nb-nitride.« less

  5. 40 CFR 420.46 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...

  6. 40 CFR 420.46 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...

  7. 40 CFR 420.46 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...

  8. 40 CFR 420.46 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... new source subject to this subpart which introduces pollutants into a publicly owned treatment works...) Basic oxygen furnace steelmaking—semi-wet; and electric arc furnace steelmaking—semi-wet. No discharge... combustion; electric arc furnace steelmaking—wet. Subpart D Pollutant or pollutant property Pretreatment...

  9. Reasonable Temperature Schedules for Cold or Hot Charging of Continuously Cast Steel Slabs

    NASA Astrophysics Data System (ADS)

    Li, Yang; Chen, Xin; Liu, Ke; Wang, Jing; Wen, Jin; Zhang, Jiaquan

    2013-12-01

    Some continuously cast steel slabs are sensitive to transverse fracture problems during transportation or handling away from their storage state, while some steel slabs are sensitive to surface transverse cracks during the following rolling process in a certain hot charging temperature range. It is revealed that the investigated steel slabs with high fracture tendency under room cooling condition always contain pearlite transformation delayed elements, which lead to the internal brittle bainitic structure formation, while some microalloyed steels exhibit high surface crack susceptibility to hot charging temperatures due to carbonitride precipitation. According to the calculated internal cooling rates and CCT diagrams, the slabs with high fracture tendency during cold charging should be slowly cooled after cutting to length from hot strand or charged to the reheating furnace directly above their bainite formation temperatures. Based on a thermodynamic calculation for carbonitride precipitation in austenite, the sensitive hot charging temperature range of related steels was revealed for the determination of reasonable temperature schedules.

  10. PSpice Model of Lightning Strike to a Steel Reinforced Structure

    NASA Astrophysics Data System (ADS)

    Koone, Neil; Condren, Brian

    2003-12-01

    Surges and arcs from lightning can pose hazards to personnel and sensitive equipment, and processes. Steel reinforcement in structures can act as a Faraday cage mitigating lightning effects. Knowing a structure's response to a lightning strike allows hazards associated with lightning to be analyzed. A model of lightning's response in a steel reinforced structure has been developed using PSpice (a commercial circuit simulation). Segments of rebar are modeled as inductors and resistors in series. A program has been written to take architectural information of a steel reinforced structure and "build" a circuit network that is analogous to the network of reinforcement in a facility. A severe current waveform (simulating a 99th percentile lightning strike), modeled as a current source, is introduced in the circuit network, and potential differences within the structure are determined using PSpice. A visual three-dimensional model of the facility displays the voltage distribution across the structure using color to indicate the potential difference relative to the floor. Clear air arcing distances can be calculated from the voltage distribution using a conservative value for the dielectric breakdown strength of air. Potential validation tests for the model will be presented.

  11. Numerical Study of the Reduction Process in an Oxygen Blast Furnace

    NASA Astrophysics Data System (ADS)

    Zhang, Zongliang; Meng, Jiale; Guo, Lei; Guo, Zhancheng

    2016-02-01

    Based on computational fluid dynamics, chemical reaction kinetics, principles of transfer in metallurgy, and other principles, a multi-fluid model for a traditional blast furnace was established. The furnace conditions were simulated with this multi-fluid mathematical model, and the model was verified with the comparison of calculation and measurement. Then a multi-fluid model for an oxygen blast furnace in the gasifier-full oxygen blast furnace process was established based on this traditional blast furnace model. With the established multi-fluid model for an oxygen blast furnace, the basic characteristics of iron ore reduction process in the oxygen blast furnace were summarized, including the changing process of the iron ore reduction degree and the compositions of the burden, etc. The study found that compared to the traditional blast furnace, the magnetite reserve zone in the furnace shaft under oxygen blast furnace condition was significantly reduced, which is conducive to the efficient operation of blast furnace. In order to optimize the oxygen blast furnace design and operating parameters, the iron ore reduction process in the oxygen blast furnace was researched under different shaft tuyere positions, different recycling gas temperatures, and different allocation ratios of recycling gas between the hearth tuyere and the shaft tuyere. The results indicate that these three factors all have a substantial impact on the ore reduction process in the oxygen blast furnace. Moderate shaft tuyere position, high recycling gas temperature, and high recycling gas allocation ratio between hearth and shaft could significantly promote the reduction of iron ore, reduce the scope of the magnetite reserve zone, and improve the performance of oxygen blast furnace. Based on the above findings, the recommendations for improvement of the oxygen blast furnace design and operation were proposed.

  12. Optimization of Dimensional accuracy in plasma arc cutting process employing parametric modelling approach

    NASA Astrophysics Data System (ADS)

    Naik, Deepak kumar; Maity, K. P.

    2018-03-01

    Plasma arc cutting (PAC) is a high temperature thermal cutting process employed for the cutting of extensively high strength material which are difficult to cut through any other manufacturing process. This process involves high energized plasma arc to cut any conducting material with better dimensional accuracy in lesser time. This research work presents the effect of process parameter on to the dimensional accuracy of PAC process. The input process parameters were selected as arc voltage, standoff distance and cutting speed. A rectangular plate of 304L stainless steel of 10 mm thickness was taken for the experiment as a workpiece. Stainless steel is very extensively used material in manufacturing industries. Linear dimension were measured following Taguchi’s L16 orthogonal array design approach. Three levels were selected to conduct the experiment for each of the process parameter. In all experiments, clockwise cut direction was followed. The result obtained thorough measurement is further analyzed. Analysis of variance (ANOVA) and Analysis of means (ANOM) were performed to evaluate the effect of each process parameter. ANOVA analysis reveals the effect of input process parameter upon leaner dimension in X axis. The results of the work shows that the optimal setting of process parameter values for the leaner dimension on the X axis. The result of the investigations clearly show that the specific range of input process parameter achieved the improved machinability.

  13. An Alternative Cu-Based Bond Layer for Electric Arc Coating Process

    NASA Astrophysics Data System (ADS)

    Fadragas, Carlos R.; Morales, E. V.; Muñoz, J. A.; Bott, I. S.; Lariot Sánchez, C. A.

    2011-12-01

    A Cu-Al alloy has been used as bond coat between a carbon steel substrate and a final coating deposit obtained by applying the twin wire electric arc spraying coating technique. The presence of a copper-based material in the composite system can change the overall temperature profile during deposition because copper exhibits a thermal conductivity several times higher than that of the normally recommended bond coat materials (such as nickel-aluminum alloys or nickel-chromium alloys). The microstructures of 420 and 304 stainless steels deposited by the electric arc spray process have been investigated, focusing attention on the deposit homogeneity, porosity, lamellar structure, and microhardness. The nature of the local temperature gradient during deposition can strongly influence the formation of the final coating deposit. This study presents a preliminary study, undertaken to investigate the changes in the temperature profile which occur when a Cu-Al alloy is used as bond coat, and the possible consequences of these changes on the microstructure and adhesion of the final coating deposit. The influence of the thickness of the bond layer on the top coating temperature has also been also evaluated.

  14. Application of Argonne's Glass Furnace Model to longhorn glass corporation oxy-fuel furnace for the production of amber glass.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Golchert, B.; Shell, J.; Jones, S.

    2006-09-06

    The objective of this project is to apply the Argonne National Laboratory's Glass Furnace Model (GFM) to the Longhorn oxy-fuel furnace to improve energy efficiency and to investigate the transport of gases released from the batch/melt into the exhaust. The model will make preliminary estimates of the local concentrations of water, carbon dioxide, elemental oxygen, and other subspecies in the entire combustion space as well as the concentration of these species in the furnace exhaust gas. This information, along with the computed temperature distribution in the combustion space may give indications on possible locations of crown corrosion. An investigation intomore » the optimization of the furnace will be performed by varying several key parameters such as the burner firing pattern, exhaust number/size, and the boost usage (amount and distribution). Results from these parametric studies will be analyzed to determine more efficient methods of operating the furnace that reduce crown corrosion. Finally, computed results from the GFM will be qualitatively correlated to measured values, thus augmenting the validation of the GFM.« less

  15. Multiple hearth furnace for reducing iron oxide

    DOEpatents

    Brandon, Mark M [Charlotte, NC; True, Bradford G [Charlotte, NC

    2012-03-13

    A multiple moving hearth furnace (10) having a furnace housing (11) with at least two moving hearths (20) positioned laterally within the furnace housing, the hearths moving in opposite directions and each moving hearth (20) capable of being charged with at least one layer of iron oxide and carbon bearing material at one end, and being capable of discharging reduced material at the other end. A heat insulating partition (92) is positioned between adjacent moving hearths of at least portions of the conversion zones (13), and is capable of communicating gases between the atmospheres of the conversion zones of adjacent moving hearths. A drying/preheat zone (12), a conversion zone (13), and optionally a cooling zone (15) are sequentially positioned along each moving hearth (30) in the furnace housing (11).

  16. A novel post-arc current measuring equipment based on vacuum arc commutation and arc blow

    NASA Astrophysics Data System (ADS)

    Liao, Minfu; Ge, Guowei; Duan, Xiongying; Huang, Zhihui

    2017-07-01

    The paper proposes a novel post-arc current measuring equipment (NPACME), which is based on the vacuum arc commutation and magnetic arc blow. The NPACME is composed of the vacuum circuit breaker (VCB), shunt resistor, protective gap, high-precision current sensor and externally applied transverse magnetic field (ETMF). The prototype of the NPACME is designed and controlled by optical fiber communications. The vacuum arc commutation between the vacuum arc and the shunt resistor with ETMF is investigated. The test platform is established in the synthetic short-circuit test and the vacuum arc is observed by the high speed CMOS camera. The mathematic description of the vacuum arc commutation is obtained. Based on the current commutation characteristic, the parameters of the NPACME are optimized and the post-arc current is measured. The measuring result of the post-arc current is accurate with small interference and the post-arc charge is obtained. The experimental results verify that the NPACME is correct and accurate, which can be used to measure the post-arc characteristic in breaking test.

  17. ARC and Melting Efficiency of Plasma ARC Welds

    NASA Technical Reports Server (NTRS)

    McClure, J. C.; Nunes, A. C.; Evans, D. M.

    1999-01-01

    A series of partial penetration Variable Polarity Plasma Arc welds were made at equal power but various combinations of current and voltage on 2219 Aluminum. Arc efficiency was measured calorimetrically and ranged between 48% and 66% for the conditions of the welds. Arc efficiency depends in different ways on voltage and current. The voltage effect dominates. Raising voltage while reducing current increases arc efficiency. Longer, higher voltage arcs are thought to transfer a greater portion of arc power to the workpiece through shield gas convection. Melting efficiency depends upon weld pool shape as well as arc efficiency. Increased current increases the melting efficiency as it increases the depth to width ratio of the weld pool. Increased plasma gas flow does the same thing. Higher currents are thought to raise arc pressure and depress liquid at the bottom of the weld pool. More arc power then transfers to the workpiece through increasing plasma gas convection. If the power is held constant, the reduced voltage lowers the arc efficiency, while the pool shape change increases the melting efficiency,

  18. Experimental Study on the Fire Performance of Tubular Steel Columns with Membrane Protections for Prefabricated and Modular Steel Construction

    PubMed Central

    Zhang, Xin; Peng, Lei; Ni, Zhao-peng; Ni, Tian-xiao; Huang, Yi-liang; Zhou, Yang

    2018-01-01

    Experimental research was conducted to study the fire resistance of steel tubular columns used in prefabricated and modular construction. In order to achieve high-efficient prefabrication and fast on-site installation, membrane protections using board products and thermal insulation blankets are adopted as the favorable protection method. Three protected tubular columns were tested in a full-scale column furnace with axial load applied. The study variables were different membranes, including fiber reinforced calcium silicate (FRCS) boards, rock wool and aluminum silica (Fiberfrax) insulations. The results suggest that one layer of 12 mm FRCS board with rock wool insulation has insufficient fire protection. However, steel columns protected with two layers of 12 mm FRCS boards with insulation appeared to have good fire resistances and could achieve a fire resistance rating as high as 2.5~3.0 h. PMID:29547574

  19. [Characteristic of Mercury Emissions and Mass Balance of the Typical Iron and Steel Industry].

    PubMed

    Zhang, Ya-hui; Zhang, Cheng; Wang, Ding-yong; Luo, Cheng-zhong; Yang, Xi; Xu, Feng

    2015-12-01

    To preliminarily discuss the mercury emission characteristics and its mass balance in each process of the iron and steel production, a typical iron and steel enterprise was chosen to study the total mercury in all employed materials and estimate the input and output of mercury during the steel production process. The results showed that the mercury concentrations of input materials in each technology ranged 2.93-159.11 µg · kg⁻¹ with the highest level observed in ore used in blast furnace, followed by coal of sintering and blast furnace. The mercury concentrations of output materials ranged 3.09-18.13 µg · kg⁻¹ and the mercury concentration of dust was the highest, followed by converter slag. The mercury input and the output in the coking plant were 1346.74 g · d⁻¹ ± 36.95 g · d⁻¹ and 177.42 g · d⁻¹ ± 13.73 g · d⁻¹, respectively. In coking process, mercury mainly came from the burning of coking coal. The sintering process was the biggest contributor for mercury input during the iron and steel production with the mercury input of 1075. 27 g · d⁻¹ ± 60.89 g · d⁻¹ accounting for 68.06% of the total mercury input during this production process, and the ore powder was considered as the main mercury source. For the solid output material, the output in the sintering process was 14.15 g · d⁻¹ ± 0.38 g · d⁻¹, accounting for 22.61% of the total solid output. The mercury emission amount from this studied iron and steel enterprise was estimated to be 553.83 kg in 2013 with the emission factor of 0.092 g · t⁻¹ steel production. Thus, to control the mercury emissions, iron and steel enterprises should combine with production practice, further reduce energy consumption of coking and sintering, or improve the quality of raw materials and reduce the input of mercury.

  20. Improved graphite furnace atomizer

    DOEpatents

    Siemer, D.D.

    1983-05-18

    A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.