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Sample records for arc furnace steel

  1. 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.

  2. Characterization of steel mill electric-arc furnace dust.

    PubMed

    Sofilić, Tahir; Rastovcan-Mioc, Alenka; Cerjan-Stefanović, Stefica; Novosel-Radović, Vjera; Jenko, Monika

    2004-06-18

    In order to make a complete characterization of electric-arc furnace (EAF) dust, as hazardous industrial waste, and to solve its permanent disposal and/or recovery, bearing in mind both the volumes formed in the Croatian steel industry and experiences of developed industrial countries, a study of its properties was undertaken. For this purpose, samples of EAF dust, taken from the regular production process in the Zeljezara Sisak Steel Mill between December 2000 and December 2001, were subjected to a series of tests. The chemical composition of EAF dust samples was investigated by means of a several different analytical methods. The results from the chemical analysis show that the approximate order of abundance of major elements in EAF dusts is as follows: Fe, Zn, Mn, Ca, Mg, Si, Pb, S, Cr, Cu, Al, C, Ni, Cd, As and Hg. Granular-metric composition of single samples was determined by applying sieve separation. Scanning electron micro-structural examination of EAF dust microstructure was performed and results indicated that all twelve EAF dusts were composed of solid spherical agglomerates with Fe, Zn, Pb, O, Si and Ca as the principal element. The investigation of grain morphology and the mineralogical composition of EAF dust were taken by combination of high resolution Auger electron spectroscopy (HR AES), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction analysis. The analysis of XPS-spectra determined the presence of zinc in the form of ZnO phase and the presence of lead in the form of PbO phase, i.e. PbSO3/PbSO4 forms. The results of the X-ray diffraction phase analysis show that the basis of the examined EAF dust samples is made of a mixture of metal oxides, silicates and sulphates. The metal concentration, anions, pH value and conductivity in water eluates was determined in order to define the influence of EAF dust on the environment.

  3. Analysis of arc emission spectra of stainless steel electric arc furnace slag affected by fluctuating arc voltage.

    PubMed

    Aula, Matti; Mäkinen, Ari; Fabritius, Timo

    2014-01-01

    Control of chromium oxidation in the electric arc furnace (EAF) is a significant problem in stainless steel production due to variations of the chemical compositions in the EAF charge. One potential method to control chromium oxidation is to analyze the emission spectrum of the electric arc in order to find indicators of rising chromium content in slag. The purpose of this study was to determine if slag composition can be gained by utilizing electric arc emission spectra in the laboratory environment, despite electric arc voltage fluctuations and varying slag composition. The purpose of inducing voltage fluctuation was to simulate changes in the industrial EAF process. The slag samples were obtained from Outokumpu Stainless Oy Tornio Works, and three different arc currents were used. The correlation analysis showed that the emission spectra offer numerous peak ratios with high correlations to the X-ray fluorescence-measured slag CrO(x)/FeO(x) and MnO/SiO2 ratios. These ratios are useful in determining if the reduction agents have been depleted in the EAF. The results suggest that analysis of laboratory-scale electric arc emission spectra is suitable for indicating the high CrO(x) or MnO content of the slag despite the arc fluctuations. Reliable analysis of other slag components was not successful.

  4. Properties of steel foundry electric arc furnace dust solidified/stabilized with Portland cement.

    PubMed

    Salihoglu, Guray; Pinarli, Vedat; Salihoglu, Nezih Kamil; Karaca, Gizem

    2007-10-01

    Electric arc furnace dust from steel production is generated in considerable amounts worldwide and needs to be treated as hazardous waste. The aim of this study was to investigate the properties of electric arc furnace dust solidified/stabilized by using Portland cement. Mortar and paste samples were prepared with varying waste-to-binder ratios between 0% and 90%. A comprehensive experimental program was designed including XRF characterization, setting time, unconfined compressive strength, and toxicity characteristics leaching procedure (TCLP), synthetic precipitation leaching procedure (SPLP), and acid neutralization capacity (ANC) tests. The results were evaluated in order to determine if the solidified /stabilized product can be disposed of at a landfill site with domestic waste or at a segregated landfill. The effect of using sand on S/S performance was also investigated. The results indicated that the solidification /stabilization process using PC helps the heavy metals to be bound in the cement matrix, but the TCLP leaching results exceeded the EPA landfilling limits. The SPLP leaching results conformed to the limits implying that the waste or S/S products can be disposed of at a segregated landfill; however the low ANC of the S/S products reveals that there may be leaching in the long-term. The sand used in the mortar samples adversely affected the S/S performance, causing higher heavy metal leaching levels, and lower pH levels in the leachate after the TCLP extraction than those measured in the leachate of the paste samples.

  5. Electric arc furnaces for steel-making: hot spots for persistent organic pollutants.

    PubMed

    Odabasi, Mustafa; Bayram, Abdurrahman; Elbir, Tolga; Seyfioglu, Remzi; Dumanoglu, Yetkin; Bozlaker, Ayse; Demircioglu, Hulusi; Altiok, Hasan; Yatkin, Sinan; Cetin, Banu

    2009-07-15

    Persistent organic pollutant (POP) concentrations were measured in stack-gases of ferrous scrap processing steel plants with electric arc furnaces (EAFs) (n = 5) in Aliaga, Izmir, Turkey and in air (n = 11) at a site near those plants. Measured stack-gas concentrations for the four plants without scrap preheating (611 +/- 311, 165,000 +/- 285,000, and 33 +/- 3 ng m(-3), average +/- SD for sigma41PCBs, sigma16PAHs, and sigma7PBDEs, respectively) indicated that they are significant sources for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). POP emissions from the plant with scrap preheating were significantly higher (13 500, 445 000, and 91 ng m(-3) for sigma41PCBs, sigma16PAHs, and sigma7PBDEs, respectively). It was also shown that the steel plants emit considerable amounts of fugitive POPs in particle-phase. Estimated emissions using the emission factors generated in this study and the production amounts suggested that the steel plants with EAFs may significantly contribute to local and global PAH, PCB, and PBDE emissions. Several other compounds (aromatic and aliphatic hydrocarbons, oxygen, sulfur, nitrogen, and chlorine-containing organic compounds, n = 49) were identified and determined semiquantitatively in the stack-gas and ambient air samples. Ambient air concentrations (62 +/- 35, 320 +/- 134 ng m(-3), 1451 +/- 954 pg m(-3), for sigma41PCBs, sigma16PAHs, and sigma7PBDEs, respectively) were significantly higher than those measured previously around the world and in the region, further confirming that the steel plants with EAFs are "hot spots" for POPs.

  6. Polychlorinated naphthalene (PCN) emissions from scrap processing steel plants with electric-arc furnaces.

    PubMed

    Odabasi, Mustafa; Dumanoglu, Yetkin; Kara, Melik; Altiok, Hasan; Elbir, Tolga; Bayram, Abdurrahman

    2017-01-01

    Polychlorinated naphthalene (PCN) emissions of scrap iron processing steel plants were explored by measuring concentrations in stack gases of five plants, in the atmosphere (n=11) at a site close to those plants, and in soil at several sites in the region (n=40) in Aliaga, Izmir, Turkey. Observed stack-gas Σ32PCN levels from the plants without scrap preheating (189±157ngNm(-3), average±SD, n=4) showed that they are substantial PCN emitting sources. Stack-gas Σ32PCN level for the plant with scrap preheating was considerably higher (1262ngNm(-3)). Similarly, Σ32PCN emission factor for this plant was substantially higher (11.9mgton(-1)) compared to those without scrap preheating (1.30±0.98mgton(-1)). Results have also suggested that the investigated steel plants emit large quantities of fugitive particle-phase PCNs. Measured soil Σ32PCN concentrations that are considered to be representative of the atmospheric levels were greatly variable in the region, ranging between 0.003 and 10.02μgkg(-1) (dry wt). Their spatial distribution showed that main PCN sources in the region were the iron-steel plants. Ambient air levels (1620±800pgm(-3)) were substantially higher than ones observed around the world and in the study area verifying that the steel plants with electric arc furnaces (EAFs) are important PCN sources. Investigation of possible mechanisms suggested that the combustion processes also contribute to emissions from EAFs in addition to evaporation of PCNs present in the scrap iron.

  7. Characterization and leachability of electric arc furnace dust made from remelting of stainless steel.

    PubMed

    Laforest, Guylaine; Duchesne, Josée

    2006-07-31

    Electric arc furnace dust (EAFD) is a toxic waste product made in the remelting of scrap steel. The results of a Toxicity Characteristic Leaching Procedure (TCLP) conducted on a sample of EAFD originating from the remelting of stainless steel scrap showed that the total Cr and Cr (VI) liquor concentrations (9.7 and 6.1 mg/L, respectively) exceeded the Toxicity Characteristic Regulatory Level (TCRL). The EAFD showed a complex heterogeneous mineralogy with spinel minerals group predominance. A sequential extractions method has permitted the determination of the amount of available metals (potentially mobile component) from the EAFD as follows: Cr (3%), Ni (6%), Pb (49%) and Zn (40%). Solubility controls on Cr, Pb, Zn and Ni were identified in the EAFD. This means that the Cr, Pb, Zn and Ni concentrations in solution were controlled by the solubility of some phases from EAFD. The concentrations of Ni and Zn, which are metals not regulated by TCRL were below 0.41 and 1.3 mg/L, respectively. The solubility control on Pb was sufficient to decrease its concentration (<0.24 mg/L) to a level below the TCRL. However, the control on Cr was not sufficient to decrease its concentration (between 117 and 331 mg/L) to below the TCRL.

  8. [Phosphorus adsorption and regeneration of electric arc furnace steel slag as wetland medium].

    PubMed

    Zhai, Li-hua; He, Lian-sheng; Xi, Bei-dou; Chen, Yue; Meng, Rui; Huo, Shou-liang; Liu, Hong-liang

    2008-12-01

    The long-term phosphorus (P) adsorption and retention capacities of electric arc furnace (EAF) steel slag materials derived from one batch and a 278-d column experiments with a synthetic P solution were compared. The investigations of the regeneration of the P adsorption capacity by water level decrease was conducted. It was revealed column experiment on a long-term basis can determine P saturation of EAF accurately. And the results can be used for realistic estimations of constructed wetland systems (CWS) longevity. EAF slag showed a high afinity for P, reaching a saturation value of 1.65 g/kg. Regeneration experiment of the P adsorbing capacity by this material showed that, after 4 weeks of water level decrease, EAF steel slag was able to increase its initial P adsorption capacity to 2.65 g/kg. A sequential P fractionation experiment was performed to quantify the proportion of P bound to mineral compounds in EAF. From the most loosely bound to the most strongly bound P fraction, P1 was associated with resin extractable (13%), Fe extractable (0.5 mol/L Na2CO3, 39%), Al extractable (0.1 mol/L NaOH, 21%), Ca extractable (1 mol/L HCl, 13%), and Ca in a stable residual pool (concentrated hot HCl, 14%). X-ray fluorescence analyses of EAF steel slag chemical composition revealed that the continuous application of a P solution resulted in 300% and 170% increases in K2O and P2O5, respectively. Al2O3 and FeO increased by 8%, while the portion of CaO remained unchanged. The investigated properties (P retention potential, regeneration of P adsorption, P fractionation) provide useful data about the suitability of slag material as a media for longterm P removal and dry-wet operation can improve P retention capacity of EAF to prolong the longevity of full-scale CWS.

  9. Assessment of hexavalent chromium release in Malaysian electric arc furnace steel slag for fertilizer usage

    NASA Astrophysics Data System (ADS)

    Bankole, L. K.; Rezan, S. A.; Sharif, N. M.

    2014-03-01

    This study investigates the leaching of hexavalent chromium (Cr (VI)) from electric arc furnace steel slag as Cr (VI) is classified as human carcinogen. Batch leaching tests were performed for 16 days. The lixiviants used were alkaline, de-ionized and rain water. After 16 days, Cr (VI) was found to be highest in alkaline water (0.03 mg/L) and lowest in de-ionized water (0.01 mg/L). Besides the lixiviants used, slag stirring speed and liquid to solid ratio also affect Cr (VI) released. The experimental work was complimented with slag characterization using XRF, XRD and SEM/EDX analysis. The leaching process was also simulated via Factsage software to calculate isothermal pourbaix diagrams. The Cr (VI) released was low and below the threshold of 0.1 mg/L set for public water systems. Recycle the slag as fertilizer should be considered safe as it does not exceed the safety limit set for Cr (VI) dissolution.

  10. 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.

  11. Valorisation of electric arc furnace steel slag as raw material for low energy belite cements.

    PubMed

    Iacobescu, R I; Koumpouri, D; Pontikes, Y; Saban, R; Angelopoulos, G N

    2011-11-30

    In this paper, the valorisation of electric arc furnace steel slag (EAFS) in the production of low energy belite cements is studied. Three types of clinkers were prepared with 0 wt.% (BC), 5 wt.% (BC5) and 10 wt.% (BC10) EAFS, respectively. The design of the raw mixes was based on the compositional indices lime saturation factor (LSF), alumina ratio (AR) and silica ratio (SR). The clinkering temperature was studied for the range 1280-1400°C; firing was performed at 1380°C based on the results regarding free lime and the evolution of microstructure. In order to activate the belite, clinkers were cooled fast by blown air and concurrent crushing. The results demonstrate that the microstructure of the produced clinkers is dominated by belite and alite crystals, with tricalcium aluminate and tetracalcium-alumino-ferrite present as micro-crystalline interstitial phases. The prepared cements presented low early strength development as expected for belite-rich compositions; however the 28-day results were 47.5 MPa, 46.6 MPa and 42.8 MPa for BC, BC5 and BC10, respectively. These values are comparable with OPC CEMI 32.5 N (32.5-52.5 MPa) according to EN 197-1. A fast setting behaviour was also observed, particularly in the case of BC10, whereas soundness did not exceed 1mm.

  12. Steel foundry electric arc furnace dust management: stabilization by using lime and Portland cement.

    PubMed

    Salihoglu, Guray; Pinarli, Vedat

    2008-05-30

    The purpose of this study was to determine an appropriate treatment for steel foundry electric arc furnace dust (EAFD) prior to permanent disposal. Lime and Portland cement (PC)-based stabilization was applied to treat the EAFD that contains lead and zinc above the landfilling limits, and is listed by USEPA as hazardous waste designation K061 and by EU as 10 02 07. Three types of paste samples were prepared with EAFD content varying between 0 and 90%. The first type contained the EAFD and Portland cement, the second contained the EAFD, Portland cement, and lime, and the third contained the EAFD and lime. All the samples were subjected to toxicity characteristics leaching procedure (TCLP) after an air-curing period of 28 days. pH changes were monitored and acid neutralization capacity of the samples were examined. Treatment effectiveness was evaluated in terms of reducing the heavy metal leachability to the levels below the USEPA landfilling criteria. An optimum composition for the EAFD stabilization was formulated as 30% EAFD +35% lime +35% Portland cement to achieve the landfilling criteria. The pH interval, where the solubility of the heavy metals in the EAFD was minimized, was found to be between 8.2 and 9.4.

  13. 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.

  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.

  15. 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.

  16. Model of phosphorus precipitation and crystal formation in electric arc furnace steel slag filters.

    PubMed

    Claveau-Mallet, Dominique; Wallace, Scott; Comeau, Yves

    2012-02-07

    The objective of this study was to develop a phosphorus retention mechanisms model based on precipitation and crystallization in electric arc furnace slag filters. Three slag columns were fed during 30 to 630 days with a reconstituted mining effluent at different void hydraulic retention times. Precipitates formed in columns were characterized by X-ray diffraction and transmission electronic microscopy. The proposed model is expressed in the following steps: (1) the rate limiting dissolution of slag is represented by the dissolution of CaO, (2) a high pH in the slag filter results in phosphorus precipitation and crystal growth, (3) crystal retention takes place by filtration, settling and growth densification, (4) the decrease in available reaction volume is caused by crystal and other particulate matter accumulation (and decrease in available reaction time), and (5) the pH decreases in the filter over time if the reaction time is too low (which results in a reduced removal efficiency). Crystal organization in a slag filter determines its phosphorus retention capacity. Supersaturation and water velocity affect crystal organization. A compact crystal organization enhances the phosphorus retention capacity of the filter. A new approach to define filter performance is proposed: saturation retention capacity is expressed in units of mg P/mL voids.

  17. Advanced steel reheat furnace

    SciTech Connect

    Moyeda, D.; Sheldon, M.; Koppang, R.; Lanyi, M.; Li, X.; Eleazer, B.

    1997-10-01

    Energy and Environmental Research Corp. (EER) under a contract from the Department of Energy is pursuing the development and demonstration of an Advanced Steel Reheating Furnace. This paper reports the results of Phase 1, Research, which has evaluated an advanced furnace concept incorporating two proven and commercialized technologies previously applied to other high temperature combustion applications: EER`s gas reburn technology (GR) for post combustion NOx control; and Air Product`s oxy-fuel enrichment air (OEA) for improved flame heat transfer in the heating zones of the furnace. The combined technologies feature greater production throughput with associated furnace efficiency improvements; lowered NOx emissions; and better control over the furnace atmosphere, whether oxidizing or reducing, leading to better control over surface finish.

  18. Health status of male steel workers at an electric arc furnace (EAF) in Trentino, Italy.

    PubMed

    Cappelletti, Roberto; Ceppi, Marcello; Claudatus, Justina; Gennaro, Valerio

    2016-01-01

    The aim of this retrospective cohort study was to determine if the workers of an Electric Arc Furnace (EAF), which recycles scrap, had higher mortality and morbidity due to possible exposure to pollutants at work. EAFs do not run on coke ovens. In EAFs 40 % of the particulate matter (PM) is made up of PM 2.5. The foundry dust contained iron, aluminum, zinc, manganese, lead, chromium, nickel, cadmium, mercury, arsenic, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls and dioxins. Mortality study: a cohort of 331 exposed workers (6731 person-years) was studied from 19/03/1979 to 31/12/2009 (mean follow up 20.7 years). The group of exposed workers was compared to the general population and to a small control group of 32 workers from the same company. Morbidity study: rates of exemption from health fee for the seven major diseases of 235 exposed workers were compared to the rates of exemption in the Province of Trento. Mortality study: an excess mortality was found in the exposed workers as compared to the general population (SMR 1.13; 95 % CI: 0.76-1.62; 29 deaths) and to the internal group (RR 2.34; 95 % CI: 0.39-95.7). The mortality rate was increased for all tumours (SMR 1.36; 95 % CI: 0.75-2.29; 14 cases), for lung cancer (SMR 3.35; 95 % CI 1.45-6.60; 8 cases), for ischemic heart disease (SMR 1.27; 95 % CI: 0.35-3.26; 4 cases), for chronic liver disease (SMR 1.16; 95 % CI: 0.14-4.20; 2 cases) and for injury and poisoning (SMR 1.32; 95 % CI: 0.48-2.88; 6 cases). Morbidity study: there was a statistically significant increase of diabetes, rheumatoid arthritis, hypertension and cardiovascular diseases in exposed workers. With the limitations of this relatively small cohort, we found a statistically significant increase of diabetes, cardiovascular diseases and deaths due to lung cancer in exposed workers. These findings cannot be explained by PAH exposure alone; metal particulates are the most important pollutants in the working area of EAFs

  19. 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.

  20. [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.

  1. 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.

  2. Acoustic characteristics of electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Cherednichenko, V. S.; Bikeev, R. A.; Cherednichenko, A. V.; Ognev, A. M.

    2016-06-01

    A mathematical model is constructed to describe the appearance and development of the noise characteristics of superpower electric arc furnaces. The noise formation is shown to be related to the pulsation of the axial plasma flows in arc discharges because of the electrodynamic pressure oscillations caused by the interaction of the self-magnetic field with the current passing in an arc. The pressure in the arc axis changes at a frequency of 100 Hz at the maximum operating pressure of 66 kPa for an arc current of 80 kA. The main ac arc sound frequencies are multiples of 100 Hz, which is supported in the practice of operation of electric arc furnaces. The sound intensity in the furnace laboratory reaches 160 dB and is decreased to 115-120 dB in the working furnace area due to shielding by the furnace jacket, the molten metal, and the molten slag. The appropriateness of increasing the hermetic sealing of electric furnaces and creating furnaces operating at low currents and high transformer voltages is corroborated.

  3. Vitrification of electric arc furnace dusts.

    PubMed

    Pelino, M; Karamanov, A; Pisciella, P; Crisucci, S; Zonetti, D

    2002-01-01

    Electric arc furnace baghouse dust (EAFD), a waste by-product of the steelmaking process, contains the elements that are volatilized from the charge during the melting (Cr, Pb, Zn, Cu and Cd). The results of leaching tests show that the concentration of these elements exceeds the regulatory limits. Consequently, EAFD cannot be disposed of in ordinary landfill sites without stabilization of the heavy metals. In this work, the vitrification of EAFD, from both carbon and stainless steel productions, were studied. The vitrification process was selected as the inertizing process because it permits the immobilization of the hazardous elements in the glass network and represents an environmentally acceptable method for the stabilization of this waste. Classes of various compositions were obtained by mixing EAFD with glass cullet and sand. The EAFD and the glass products were characterized by DTA, TG, X-ray analysis and by the TCLP test. The results show that the stability of the product is influenced by the glass structure, which mainly depends on the Si/O ratio. Secondary crystallization heat-treatment were carried out on some samples. The results highlighted the formation of spinel phases, which reduced the chemical durability in acid media. The possibility to recover Zn from carbon steel production EAFD was investigated and about 60-70% of metal recovery was obtained. The resulting glass show higher chemical stability than glasses obtained without metal recovery.

  4. Effect of the chemical composition of slag on its foamability in an electric arc furnace

    NASA Astrophysics Data System (ADS)

    Kozhukhov, A. A.

    2015-06-01

    The problems of foaming electric furnace slags are considered. The role of the physicochemical properties of slag during its foaming in electric arc furnaces is studied. The regions of slag foaming in an electric arc furnace are determined. Based on the derived relations between the chemical composition of slag and its foamability, one can choose a rational path of slag formation to ensure good slag foaming in the course of electrosmelting of steel.

  5. 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.

  6. Processing electric arc furnace dust into saleable chemical products

    SciTech Connect

    1998-04-01

    The modern steel industry uses electric arc furnace (EAF) technology to manufacture steel. A major drawback of this technology is the production of EAF dust, which is listed by the U.S. Environmental Protection Agency as a hazardous waste under the Resource Conservation and Recovery Act. The annual disposal of approximately 0.65 million tons of EAF dust in the United States and Canada is an expensive, unresolved problem for the steel industry. EAF dust byproducts are generated during the manufacturing process by a variety of mechanisms. The dust consists of various metals (e.g., zinc, lead, cadmium) that occur as vapors at 1,600{degrees}C (EAF hearth temperature); these vapors are condensed and collected in a baghouse. The production of one ton of steel will generate approximately 25 pounds of EAF dust as a byproduct, which is currently disposed of in landfills.

  7. 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.

  8. Blast furnace injection developments in British Steel

    SciTech Connect

    Jukes, M.H.

    1996-12-31

    British Steel has four integrated steel works, i.e., Llanwern, Port Talbot, Scunthorpe, Teesside, with a total of ten blast furnaces, nine of which are currently operating. The furnaces range in size from the 14 meters (45 feet 11 inches) hearth diameter Redcar No. 1 furnace at Teesside (a single furnace works) to the 8.33 meters (27 feet 4 inches) hearth Queen Mary and Queen Bess furnaces at Schunthorpe, with a total of four furnaces at that works. All have injection systems installed, those at Scunthorpe being equipped with granular coal injection and all others currently working with oil injection. The driving force behind the development of blast furnace injection has been as a means for introducing reducing agents (British Steel now refers to coke plus hydrocarbon injectants as total reductants) into the process as a part substitute/supplement for top charged coke and the technology is still being developed and used for that purpose. By utilizing practical experience and observing the work of others, British Steel has been assessing blast furnace injection technology experimentally for purposes other than the introduction of reducing agents.

  9. Blast furnaces make way for new steel technology

    SciTech Connect

    Ondrey, G.; Parkinson, G.; Moore, S.

    1995-03-01

    Increasingly stringent environmental regulations, aging production units, and a competitive market are forcing iron and steelmakers to improve the environmental performance and cost efficiencies of their processes. The traditional integrated steel unit isn`t obsolete -- yet. Blast furnaces will be around for at least another 15 years. However, traditional technology is in for some changes, and stepped up rivalry from electric arc furnace minimills and ironmaking processes that use gas or coal. The paper discusses direct iron making processes, the DRI-minimill connection, the iron carbide process, and reclaiming iron from waste.

  10. 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.

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

    SciTech Connect

    Maekinen, A.; Tikkala, H.; Aksela, H.; Niskanen, J.

    2013-04-15

    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, Cr{sub 2}O{sub 3}, Ni, SiO{sub 2}, Al{sub 2}O{sub 3}, 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.

  12. TILTING ELECTRIC ARC FURNACE USED TO MELT BRONZE IN THE ...

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

    TILTING ELECTRIC ARC FURNACE USED TO MELT BRONZE IN THE BRASS FOUNDRY BY MEANS OF AN ARC CREATED BETWEEN TWO HORIZONTAL ELECTRODES. WHEN MELTED, THE FURNACE TILTS, FILLING MOBILE LADLES FROM THE SPOUT. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  13. Hydrothermal treatment of electric arc furnace dust.

    PubMed

    Yu, Bing-Sheng; Wang, Yuh-Ruey; Chang, Tien-Chin

    2011-06-15

    In this study, ZnO crystals were fabricated from electric arc furnace dust (EAFD) after alkaline leaching, purification and hydrothermal treatment. The effects of temperature, duration, pH, and solid/liquid ratio on ZnO crystal morphology and size were investigated. Results show a high reaction temperature capable of accelerating the dissolution of ZnO precursor, expediting the growth of 1D ZnO, and increasing the L/D ratio in the temperature range of 100-200°C. ZnO crystals with high purity can also be obtained, using the one-step hydrothermal treatment with a baffle that depends on the different solubility of zincite and franklinite in the hydrothermal conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. 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

  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. Computational Modeling of Arc-Slag Interaction in DC Furnaces

    NASA Astrophysics Data System (ADS)

    Reynolds, Quinn G.

    2016-11-01

    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.

  17. 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

  18. DC Arc Furnaces — Past, Present, and Future

    NASA Astrophysics Data System (ADS)

    Jones, Rodney T.

    DC arc furnaces were first used industrially for the reductive smelting of chromite fines to produce ferrochromium thirty years ago. Since then, they have been used for a variety of applications, including the smelting of ilmenite to produce titania slag and pig iron, the recovery of cobalt from non-ferrous smelter slags, and the smelting of nickel laterite ores to produce ferronickel. The power of these furnaces has increased from 12 MW to 72 MW for ferrochromium, and to 80 MW for ferronickel. The largest of these furnaces requires two electrodes to carry sufficient current to generate this much power. A review is presented of various DC arc furnaces in use, along with a discussion of the likely ways in which furnace power might be increased further in the future.

  19. Thermal Treatment of Solid Wastes Using the Electric Arc Furnace

    SciTech Connect

    O'Connor, W.K.; Turner, P.C.

    1999-09-01

    A thermal waste treatment facility has been developed at the Albany Research Center (ARC) over the past seven years to process a wide range of heterogeneous mixed wastes, on a scale of 227 to 907 kg/h (500 to 2,000 lb/h). The current system includes a continuous feed system, a 3-phase AC, 0.8 MW graphite electrode arc furnace, and a dedicated air pollution control system (APCS) which includes a close-coupled thermal oxidizer, spray cooler, baghouse, and wet scrubber. The versatility of the complete system has been demonstrated during 5 continuous melting campaigns, ranging from 11 to 25 mt (12 to 28 st) of treated wastes per campaign, which were conducted on waste materials such as (a) municipal incinerator ash, (b) simulated low-level radioactive, high combustible-bearing mixed wastes, (c) simulated low-level radioactive liquid tank wastes, (d) heavy metal contaminated soils, and (e) organic-contaminated dredging spoils. In all cases, the glass or slag products readily passed the U.S. Environmental Protection Agency (EPA) Toxicity Characteristic Leachability Program (TCLP) test. Additional studies are currently under way on electric utility wastes, steel and aluminum industry wastes, as well as zinc smelter residues. Thermal treatment of these solid waste streams is intended to produce a metallic product along with nonhazardous glass or slag products.

  20. Energy Balance in DC Arc Plasma Melting Furnace

    NASA Astrophysics Data System (ADS)

    Zhao, Peng; Meng, Yuedong; Yu, Xinyao; Chen, Longwei; Jiang, Yiman; Ni, Guohua; Chen, Mingzhou

    2009-04-01

    In order to treat hazardous municipal solid waste incinerator's (MSWI) fly ash, a new DC arc plasma furnace was developed. Taking an arc of 100 V/1000 A DC as an example, the heat transfer characteristics of the DC arc plasma, ablation of electrodes, heat properties of the fly ash during melting, heat transfer characteristics of the flue gas, and heat loss of the furnace were analyzed based on the energy conservation law, so as to achieve the total heat information and energy balance during plasma processing, and to provide a theoretical basis for an optimized design of the structure and to improve energy efficiency.

  1. Hydrometallurgically recovering zinc from electric arc furnace dusts

    NASA Astrophysics Data System (ADS)

    Antrekowitsch, J.; Antrekowitsch, H.

    2001-12-01

    The increasing use of zinc-containing scrap for steel production has lead to a high zinc content in the electric arc furnace and converter flue dusts. The cost of disposing of this residue is high due to environmental restrictions. Various recycling processes have been developed for these dusts, but most never reached the pilot plant stage and many investigations were stopped because of metallurgical and economical inefficiencies. While pyrometallurgical methods have to deal with high energy consumption, low zinc yield, and valueless residues, hydrometallurgical processes could offer an economical recycling alternative. This paper describes hydrometallurgical methods for recovering zinc from steel industry dust. These methods can be integrated in the primary zinc-winning process or in galvanization. Investigations of sulfuric-acid leaching show high zinc solubility but also a high iron content in the final liquor. As a result, steps for purification are required that cannot be conducted economically. Alternatively, a NaOH leaching gives a satisfying zinc yield and a very low solubility for the iron that remains in the residue.

  2. 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

  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. Mineral phases of weathered and recent electric arc furnace dust.

    PubMed

    Martins, Fernanda Machado; dos Reis Neto, José Manoel; da Cunha, Carlos Jorge

    2008-06-15

    A weathered and a recent sample of electric arc furnace dust (EAFD), generated in a southern Brazilian steel industry, were characterized by X-ray fluorescence spectroscopy (XFA), powder X-ray diffraction (XRD), thermogravimetric analysis (TG), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) probe and Fourier transform infrared spectroscopy (FTIR). A quantitative phase composition model, that accounts for the observed data and for the physico-chemical conditions of formation, was postulated for each material. One sample, in the form of a wet paste, was collected from the lowest part of a landfill and corresponds to a weathered material whereas the other sample was collected from the top portion of the landfill and corresponds to a recently produced material. The dominant cations present in both samples are iron, zinc and lead with minor amounts of manganese, calcium and silicon. The dominant mineralogical phases identified in both materials are Magnetite, Franklinite and Zincite. The recent sample has Laurionite whereas the weathered sample has Hydrocerussite and Hydrozincite.

  6. 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.

  7. Thermodynamic Modeling of Zinc Speciation in Electric Arc Furnace Dust

    NASA Astrophysics Data System (ADS)

    Pickles, Chris A.

    2011-04-01

    The remelting of automobile scrap, containing galvanized steel, in an electric arc furnace (EAF) results in the generation of a dust, which contains considerable amounts of zinc and other metals. Typically, the amount of zinc is of significant commercial value, but the recovery of this metal can be hindered by the varied speciation of zinc. The majority of the zinc exists as zincite (ZnO) and zinc ferrite (ZnFe2O4) or ferritic spinels ((Zn x Mn y Fe1-x-y )Fe2O4), but other zinccontaining species such as zinc chloride, zinc hydroxide chlorides, hydrated zinc sulphates and zinc silicates have also been identified. There is a scarcity of research literature on the thermodynamic aspects of the formation of these zinc-containing species, in particular, the minor zinc-containing species. Therefore, in this study, the equilibrium module of HSC Chemistry® 6.1 was utilized to calculate the types and the amounts of the zinc-containing species. The variables studied were: the gas composition, the temperature and the dust composition. At high temperatures, zincite forms via the reaction of zinc vapour with oxygen gas and the zinc-manganese ferrites form as a result of the reaction of iron-manganese particles with zinc vapour and oxygen. At intermediate temperatures, zinc sulphates are produced through the reaction of zinc oxide and sulphur dioxide gas. As room temperature is approached, zinc chlorides and fluorides form by the reaction of zinc oxide with hydrogen chloride and hydrogen fluoride gases, respectively. Zinc silicate likely forms via the high temperature reaction of zinc vapour and oxygen with silica. In the presence of excess water and as room temperature is approached, the zinc sulphates, chlorides and fluorides can become hydrated.

  8. Advanced steel reheat furnaces: Research and development. Final report

    SciTech Connect

    Nguyen, Q.; Koppang, R.; Maly, P.; Moyeda, D.; Li, X.

    1999-01-14

    The purpose of this report is to present the results of two phases of a three-phase project to develop and evaluate an Advanced Steel Reheat Furnace (SSRF) concept which incorporates two proven and commercialized technologies, oxy-fuel enriched air (OEA) combustion and gas reburning (GR). The combined technologies aim to improve furnace productivity with higher flame radiant heat transfer in the heating zones of a steel reheat furnace while controlling potentially higher NOx emissions from these zones. The project was conducted under a contract sponsored by the Department of Energy (DOE). Specifically, this report summarizes the results of a modeling study and an experimental study to define and evaluate the issues which affect the integration and performance of the combined technologies. Section 2.0 of the report describes the technical approach uses in the development and evaluation of the advanced steel reheat furnace. Section 3.0 presents results of the modeling study applied to a model steel furnace. Experimental validation of the modeling results obtained from EER`s Fuel Evaluation Facility (FEF) pilot-scale furnace discussed in Section 4.0. Section 5.0 provides an economic evaluation on the cost effectiveness of the advanced reheat furnace concept. Section 6.0 concludes the report with recommendations on the applicability of the combined technologies of steel reheat furnaces.

  9. Arc characteristics of submerged arc welding with stainless steel wire

    NASA Astrophysics Data System (ADS)

    Li, Ke; Wu, Zhi-sheng; Liu, Cui-rong; Chen, Feng-hua

    2014-08-01

    The arc characteristics of submerged arc welding (SAW) with stainless steel wire were studied by using Analysator Hannover (AH). The tests were carried out under the same preset arc voltage combined with different welding currents. By comparing the probability density distribution (PDD) curves of arc voltage and welding current, the changes were analyzed, the metal transfer mode in SAW was deduced, and the characteristics of a stable arc were summarized. The analysis results show that, with an increase of welding parameters, the short-circuiting peak in the PDD curves of arc voltage decreases gradually until it disappears, and the dominant metal transfer mode changes from flux-wall guided transfer to projected transfer and then to streaming transfer. Moreover, when the PDD curves of arc voltage are both unimodal and generally symmetrical, the greater the peak probability and the smaller the peak span, the more stable the arc becomes.

  10. Graphite electrode DC arc furnace. Innovative technology summary report

    SciTech Connect

    1999-05-01

    The Graphite Electrode DC Arc Furnace (DC Arc) is a high-temperature thermal process, which has been adapted from a commercial technology, for the treatment of mixed waste. A DC Arc Furnace heats waste to a temperature such that the waste is converted into a molten form that cools into a stable glassy and/or crystalline waste form. Hazardous organics are destroyed through combustion or pyrolysis during the process and the majority of the hazardous metals and radioactive components are incorporated in the molten phase. The DC Arc Furnace chamber temperature is approximately 593--704 C and melt temperatures are as high as 1,500 C. The DC Arc system has an air pollution control system (APCS) to remove particulate and volatiles from the offgas. The advantage of the DC Arc is that it is a single, high-temperature thermal process that minimizes the need for multiple treatment systems and for extensive sorting/segregating of large volumes of waste. The DC Arc has the potential to treat a wide range of wastes, minimize the need for sorting, reduce the final waste volumes, produce a leach resistant waste form, and destroy organic contaminants. Although the DC arc plasma furnace exhibits great promise for treating the types of mixed waste that are commonly present at many DOE sites, several data and technology deficiencies were identified by the Mixed Waste Focus Area (MWFA) regarding this thermal waste processing technique. The technology deficiencies that have been addressed by the current studies include: establishing the partitioning behavior of radionuclides, surrogates, and hazardous metals among the product streams (metal, slag, and offgas) as a function of operating parameters, including melt temperature, plenum atmosphere, organic loading, chloride concentration, and particle size; demonstrating the efficacy of waste product removal systems for slag and metal phases; determining component durability through test runs of extended duration, evaluating the effect of

  11. 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.

  12. GUI for studying the parameters influence of the electric arc model for a three-phase electric arc furnace

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

    This paper presents an analysis regarding the modeling of the behavior for a three-phase electric arc furnace installation. Therefore, a block diagram is implemented in Simulink that represents the modeling of the entire electric arc furnace installation. This block diagram contains also the modeling of the electric arc which is the element that makes the electric arc furnace behaving as a nonlinear load. The values for the model parameters of the electric arc furnace installation are like the ones from the real installation taken into consideration. Other model parameters are the electric arc model ones. In order to study the influence of the parameters of the electric arc models, it is developed a Matlab program that contains the graphical user interfaces. These interfaces make connection with the models of the electric arc implemented in Simulink. The interfaces allow the user to modify parameters for each of the electric arc model. Current and voltage of the electric arc are the variables taken into account to study the influence of the parameters on the electric arc models. Waveforms for voltage and current of the electric arc are illustrated when a parameter of the model is modified in order to analyze the importance of this parameter on the electric arc model. Also, for each of the models is presented the voltage-current characteristic of the electric arc because this characteristic gives information about the behavior of the electric arc furnace installation.

  13. 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.

  14. 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.

  15. 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

  16. Glass-ceramic materials from electric arc furnace dust.

    PubMed

    Kavouras, P; Kehagias, T; Tsilika, I; Kaimakamis, G; Chrissafis, K; Kokkou, S; Papadopoulos, D; Karakostas, Th

    2007-01-31

    Electric arc furnace dust (EAFD) was vitrified with SiO2, Na2CO3 and CaCO3 powders in an electric furnace at ambient atmosphere. Vitreous products were transformed into glass-ceramic materials by two-stage heat treatment, at temperatures determined by differential thermal analysis. Both vitreous and glass-ceramic materials were chemically stable. Wollastonite (CaSiO3) was separated from the parent matrix as the dominant crystalline phase, verified by X-ray diffraction analysis and energy dispersive spectrometry. Transmission electron microscopy revealed that wollastonite crystallizes mainly in its monoclinic form. Knoop microhardness was measured with the static indentation test method in all initial vitreous products and the microhardness values were in the region of 5.0-5.5 GPa. Devitrification resulted in glass-ceramic materials with microhardness values strongly dependent on the morphology and orientation of the separated crystal phase.

  17. 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.

  18. A rotary arc furnace for aluminum dross processing

    SciTech Connect

    Drouet, M.G.; Meunier, J.; Laflamme, C.B.; Handfield, M.D.; Biscaro, A.; Lemire, C.

    1995-12-31

    Dross, a major by-product of all processes involving molten aluminum, forms at the surface of the molten metal as the latter reacts with the furnace atmosphere. It generally represents 1 to 5 wt% of the melt, depending on the process, and contains on average about 50% free aluminum dispersed in an oxide layer. Since aluminum production is highly energy-intensive, dross recycling is very attractive from both the energy and the economic standpoints. The conventional recycling process using salt rotary furnaces is thermally inefficient and environmentally non-acceptable because of the production of salt slags. Hydro-Quebec has developed and patented a new salt-free technology using a rotary furnace heated by an electric arc between two graphite electrodes, called DROSCAR{reg_sign}. A 600-kW pilot plant in operation at LTEE is in use to demonstrate the process. This process provides aluminum recovery rates over 90%, using a highly energy efficient, environmentally sound production method. In 1994, 400 tonnes of aluminum dross were treated in this facility and several tests on various types of dross have also been conducted in early 1995. A report on the results will be presented.

  19. A rotary arc furnace for aluminum dross processing

    SciTech Connect

    Drouet, M.G.; Meunier, J.; Laflamme, C.B.; Handfield, M.D.; Biscaro, A.; Lemire, C.

    1995-12-31

    Dross, a major by-product of all processes involving molten aluminum, forms at the surface of the molten metal as the latter reacts with the furnace atmosphere. It generally represents 1 to 5 wt% of the melt, depending on the process, and contains on average about 50% free aluminum dispersed in an oxide layer. Since aluminum production is highly energy-intensive, dross recycling is very attractive from both the energy and the economic standpoints. The conventional recycling process using salt rotary furnaces is thermally inefficient and environmentally unacceptable because of the salt slags produced. Hydro-Quebec has developed and patented a new salt-free technology using a rotary furnace heated by an electric arc between two graphite electrodes, called DROSCAR{reg_sign}. A 600-kW pilot plant in operation at LTEE is in use to demonstrate the process. This process provides aluminum recovery rates for over 90%, using a highly energy efficient, environmentally sound production method. In 1994, 400 tons of aluminum dross were treated in this facility and several tests on various types of dross have also been conducted in early 1995. A report on the results will be presented.

  20. 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

    ... Hazardous Air Pollutants for Area Sources: Electric Arc Furnace Steelmaking Facilities Standards and Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of...

  1. 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

    ... Hazardous Air Pollutants for Area Sources: Electric Arc Furnace Steelmaking Facilities Standards and Compliance Requirements § 63.10686 What are the requirements for electric arc furnaces and argon-oxygen... arc furnaces and argon-oxygen decarburization vessels? 63.10686 Section 63.10686 Protection of...

  2. Blast furnace coal injection at Scunthorpe Works, British Steel plc

    SciTech Connect

    Matheau-Raven, D.

    1996-12-31

    Granulator coal injection has been practiced since 1982 at Scunthorpe Works, British Steel plc. The Works is world famous for its four Queens of Ironmaking, named Victoria, Anne, Bess and Mary. These four blast furnaces are capable of producing 4.1 million tonnes of hot metal per annum. The coal injection system was a joint development venture between British Steel and a local based company call Clyde Pneumatic Conveyors. After 14 years of operation and regulator use, Scunthorpe`s coal injection rates have risen to become among the highest in the world. Total coal injected stands at around 4 million tonnes and coal injection rates of greater than 200 kg/thm have been achieved. The furnace operation has remained smooth throughout and there have been no measurable detrimental effects upon the blast furnace performance. In fact quite the opposite with several benefits. This paper briefly describes the furnaces and the coal injection equipment. Operating results for a full twelve months are given and discussed as are aspects of the blast furnace operating practice enabling these injection rates to be achieved. In financial terms savings totaling around 14 million pounds sterling per annum have been realized through the use of blast furnace coal injection.

  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.

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

    NASA Astrophysics Data System (ADS)

    Opitz, Florian; Treffinger, Peter; Wöllenstein, Jürgen

    2017-08-01

    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.

  5. Inland Steel's No. 7 blast furnace third reline

    SciTech Connect

    Lowrance, K.F. II ); Johansson, J.; Carter, W.L. )

    1994-09-01

    The background information, investigation and benchmarking that led to a decision by Inland Steel to partially reline No. 7 blast furnace is covered. This approach reduced actual downtime on the furnace and extended the current campaign. This alternative allowed for the rebalancing of the physical plant of No. 7 blast furnace. Areas of scope covered are hearth, stack, stoves, gas cleaning and furnace top. Included are highlights of the execution of the project including schedules, blowdown, salamander tap, quench, dig out/descale, scaffolding used and brick installation. A summary of the actual results of the work is presented along with information on production planned, blow-in and the first 20 days of production.

  6. Removal of chloride from electric arc furnace dust.

    PubMed

    Chen, Wei-Sheng; Shen, Yun-Hwei; Tsai, Min-Shing; Chang, Fang-Chih

    2011-06-15

    Electric arc furnace (EAF) dust with high chloride content increases the threat of dioxin emissions and the high chloride content reduces the value of recycled zinc oxide produced by EAF dust recycling plants. This study conducts a number of laboratory experiments to determine the technical feasibility of a new dechlorination method. These methods consist of a series of roasting processes and water washing processes. In the roasting process, EAF dust was heated in a tube furnace to evaluate the parameters of atmospheric conditions, roasting temperature, and roasting time. Results indicate that sulfation roasting is more efficient in reducing chloride content than other roasting processes. The water washing process can totally remove water-soluble chloride at a solid to liquid ratio of 1:10. However, the remaining water-insoluble substance is difficult to dechlorinate. For example, lead chloride forms a hydroxyl-halide (PbOHCl) and lead chloride carbonate (Pb(2)CO(3)Cl(2)) agglutinative matrix that is hard to wash away.

  7. Nitrogen Control in Electric Arc Furnace Steelmaking by DRI (TRP 0009)

    SciTech Connect

    Dr. Gordon A. Irons

    2004-03-31

    Nitrogen is difficult to remove in electric arc furnace (EAF) steelmaking, requiring the use of more energy in the oxygen steelmaking route to produce low-nitrogen steel. The objective of this work was to determine if the injection of directly reduced iron (DRI) fines into EAFs could reduce the nitrogen content by creating fine carbon monoxide bubbles that rinse nitrogen from the steel. The proposed work included physical and chemical characterization of DRI fines, pilot-scale injection into steel, and mathematical modeling to aid in scale-up of the process. Unfortunately, the pilot-scale injections were unsuccessful, but some full-scale data was obtained. Therefore, the original objectives were met, and presented in the form of recommendations to EAF steelmakers regarding: (1) The best composition and size of DRI fines to use; (2) The amount of DRI fines required to achieve a specific reduction in nitrogen content in the steel; and (3) The injection conditions. This information may be used by steelmakers in techno-economic assessments of the cost of reducing nitrogen with this technology.

  8. 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.

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

    SciTech Connect

    Nimbalkar, Sachin U; Thekdi, Arvind; Keiser, James R; Storey, John Morse

    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 electric 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.

  10. 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.

  11. 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

  12. Optimization of anthracite calcination process in a vertical electric arc furnace

    SciTech Connect

    Perron, J.; Bouvette, J.F.; Dupuis, M.

    1996-10-01

    Anthracite is used for cathode block manufacturing must be calcined prior to its use to eliminate volatile matter and reduce its electrical resistivity. Anthracite calcination in vertical electric arc furnaces is widely used in the industry. It is well known that this technology leads to a radial temperature gradient in the furnace which results in non-homogeneous calcined anthracite properties. Also, operation experience has shown that production of calcination furnaces can be difficult to stabilize if process changes occur, which may lead to variable quality of the calcined material. To optimize the calcination process, an improved control strategy and a mathematical model of Elkem-type electric arc furnace were developed. Using these, it was successfully demonstrated that temperature gradient in the furnace can be reduced and that furnace productivity can be substantially increased.

  13. 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

    2017-02-25

    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.

  14. 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.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission... charging intermittently every minute. b Temperature measured in off-gas channel downstream of the furnace...

  15. 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

  16. 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.

  17. A review of the use of anthracite in electric arc furnace steelmaking

    SciTech Connect

    Rozelle, P.L.

    1994-12-31

    The applications of anthracite in Electric Arc Furnace (EAF) steelmaking, include the adjustment of hot metal carbon content, the generation of foamy slags, and its use as a support fuel in the EAF to reduce power consumption per tonne of product. Incentives to use support fuel in EAF steelmaking include the reduction of electric power consumption without reducing plant output. As such, the concept can reduce steelmaking costs and can serve as a basis for maximizing an EAF operation`s demand side management program. The use of carbon and oxygen additions to the EAF can cause significant release of energy within the furnace. This energy can offset a portion of the electrical energy required by the system for production of steel. Reduced consumption of electricity per tonne of hot metal is the result Electrode consumption and tap to tap times can also be reduced. significant interest in the use of anthracite as EAF support fuel, as well as the other applications of anthracite in EAF steelmaking, have combined to establish the EAF steelmaking trade as a significant market sector for anthracite. This discussion is a review of key anthracite properties and production considerations, and their interplay with the requirements of the EAF process.

  18. Modeling of zinc solubility in stabilized/solidified electric arc furnace dust.

    PubMed

    Fernández-Olmo, Ignacio; Lasa, Cristina; Irabien, Angel

    2007-06-18

    Equilibrium models which attempt for the influence of pH on the solubility of metals can improve the dynamic leaching models developed to describe the long-term behavior of waste-derived forms. In addition, such models can be used to predict the concentration of metals in equilibrium leaching tests at a given pH. The aim of this work is to model the equilibrium concentration of Zn from untreated and stabilized/solidified (S/S) electric arc furnace dust (EAFD) using experimental data obtained from a pH-dependence leaching test (acid neutralization capacity, ANC). EAFD is a hazardous waste generated in electric arc furnace steel factories; it contains significant amounts of heavy metals such as Zn, Pb, Cr or Cd. EAFD from a local factory was characterized by X-ray fluorescence (XRF), acid digestion and X-ray diffraction (XRD). Zn and Fe were the main components while the XRD analysis revealed that zincite, zinc ferrite and hematite were the main crystalline phases. Different cement/EAFD formulations ranging from 7 to 20% dry weight of cement were prepared and subjected to the ANC leaching test. An amphoteric behavior of Zn was found from the pH dependence test. To model this behavior, the geochemical model Visual MINTEQ (VMINTEQ) was used. In addition to the geochemical model, an empirical model based on the dissolution of Zn in the acidic zone and the re-dissolution of zinc compounds in the alkaline zone was considered showing a similar prediction than that obtained with VMINTEQ. This empirical model seems to be more appropriate when the metal speciation is unknown, or when if known, the theoretical solid phases included in the database of VMINTEQ do not allow to describe the experimental data.

  19. Submerged arc fillet welds between mild steel and stainless steel

    SciTech Connect

    Kotecki, D.J.; Rajan, V.B.

    1997-02-01

    Submerged arc fillet welds between mild steel and Type 304 stainless steel, made with ER309L wire, may contain no ferrite and be at risk of hot cracking, or they may be sufficiently diluted that they transform to martensite with both hot cracking risk and low ductility. This situation is most prevalent when direct current electrode positive (DCEP) polarity is used and when the flange is the mild steel part of the T-joint. A flux that adds chromium to the weld can somewhat alleviate this tendency. Direct current electrode negative (DCEN) polarity greatly reduces this tendency by limiting dilution. Fillet weld compositions and dilutions are obtained for a number of welding conditions and fluxes.

  20. Optical Sensors for Post Combustion Control in Electric Arc Furnace Steelmaking (TRP 9851)

    SciTech Connect

    Sarah W. Allendorf; David K. Ottesen; Robert W. Green; Donald R. Hardesty; Robert Kolarik; Howard Goodfellow; Euan Evenson; Marshall Khan; Ovidiu Negru; Michel Bonin; Soren Jensen

    2003-12-31

    Working in collaboration with Stantec Global Technologies, Process Metrix Corporation, and The Timken Company, Sandia National Laboratories constructed and evaluated a novel, laser-based off-gas sensor at the electric arc furnace facility of Timken's Faircrest Steel Plant (Canton, Ohio). The sensor is based on a mid-infrared tunable diode laser (TDL), and measures the concentration and temperature of specific gas species present in the off-gas emanating from the EAF. The laser beam is transmitted through the gas stream at the fourth hole of the EAF, and provides a real-time, in situ measurement that can be used for process optimization. Two sets of field tests were performed in parallel with Stantec's extractive probe off-gas system, and the tests confirm the TDL sensor's operation and applicability for electric steel making. The sensor measures real-time, in situ line-of-sight carbon monoxide (CO) concentrations between 5% and 35% CO, and measures off-gas temperature in the range of 1400 to 1900 K. In order to achieve commercial-ready status, future work is required to extend the sensor for simultaneous CO and CO{sub 2} concentration measurements. In addition, long-term endurance tests including process optimization must be completed.

  1. Innovation approaches to controlling the electric regimes of electric arc furnaces

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

    The processes of current passage in an ac electric arc furnace (EAF) are subjected to industrial experiments and mathematical simulation. It is shown that, when a charge is melted, arcs between charge fragments exist in series with main arc discharges, and these arcs influence the stability of the main arc discharges. The measurement of instantaneous currents and voltages allowed us to perform a real-time calculation of the electrical characteristics of a three-phase circuit and to determine the θ parameter, which characterizes the nonlinearity of the circuit segment between electrodes. Based on these studies, we created an advanced system for controlling the electric regime of EAF.

  2. Welding properties of thin steel sheets by laser-arc hybrid welding: laser focused arc welding

    NASA Astrophysics Data System (ADS)

    Ono, Moriaki; Shinbo, Yukio; Yoshitake, Akihide; Ohmura, Masanori

    2003-03-01

    Laser-arc hybrid welding combines the laser and arc welding processes to provide advantages not found in either. This process can weld lapped steel sheets that have a larger gap than is possible with laser welding. Blowholes form when lap-welding zinc-coated steel sheets because of the zinc that is vaporized. The laser-arc hybrid welding process can lap-weld zinc-coated steel sheets without causing blowholes. The welding speed of laser-arc hybrid welding is nearly equivalent to that of laser welding. Laser-arc hybrid welding produces high-quality lap joints and is ideal for assembly welding of automotive parts.

  3. The startup of coal injection on Bethlehem Steel`s Burns Harbor blast furnaces

    SciTech Connect

    Hill, D.G.; Strayer, T.J.; Durko, D.P.; Dwelly, M.J.

    1996-12-31

    Despite the simplicity of operation and the excellent results from natural gas injection at Bethlehem Steel, there were concerns about future supply and price stability. Furthermore, the maximum projected gas rates still required coke consumption in excess of Burns Harbor`s coke production capacity. Thus in 1990 Bethlehem Steel entered into an agreement to participate in the DOE Clean Coal Technology demonstration project by installing a granular coal injection facility at Burns Harbor. This agreement called for a facility to be constructed which was capable of processing and injecting a wide range of coal types in either granular or pulverized form. Tests were to be conducted to assess the effects of a range of coal properties, coal sizing, and injection rates on a number of key blast furnace parameters. During all the transitioning from natural gas injection to coal injection and subsequent tests it was essential that the blast furnaces maintain their historic operating performance in support of the Burns Harbor Division`s product market requirements. Unlike many coal injection facilities, the Burns Harbor installation is owned by Bethlehem Steel and the operation and maintenance from raw coal unloading through the tuyeres is the responsibility of the Blast Furnace Department. As the authors will discuss, the start-up of this major installation involved significant challenges, the most critical of which was maintaining historically high blast furnace operating standards while commissioning a new facility and adapting the furnace process to coal injection.

  4. Arc-furnace model for the study of flicker compensation in electrical networks

    SciTech Connect

    Montanari, G.C.; Loggini, M.; Cavallini, A.; Pitti, L. . Istituto di Elettrotecnica Industriale); Zaninelli, D. . Dipt. di Elettrotecnica)

    1994-10-01

    This paper presents an arc-furnace model consisting of non-linear, time varying resistance where two different time-variation laws of arc length are considered. One consists of a periodic, sinusoidal law, the other of a band-limited white-noise law. The arc-furnace model is implemented by EMTP, referring to actual electric-plant configurations. Simulations are reported where the values of flicker sensation and short-term flicker severity, P[sub ST], are determined according to UIE specifications. It results that the model based on sinusoidal time-variation law can be useful for worst-case approximations, while the model using white-noise law is able to fit flicker measurements made in electric plants supplying arc furnaces. The models are used to investigate the effect on flicker compensation of the insertion of series inductors at the supply side of the furnace transformer. It is shown that considerable reduction of P[sub ST] is obtained at the point of common coupling by series inductor installation at constant furnace active power.

  5. Analysis of harmonic and transient phenomena due to operation of a-c arc furnace

    SciTech Connect

    Sarshar, A.; Sharp, M.; Iravani, R.M.

    1995-07-01

    Operation of an a-c electric arc furnace load is associated with the generation of harmonic currents in the frequency range of fractions of Hertz up to approximately 1,000 Hz. The magnitude of these harmonic current components can be high and depends on the diverse operating condition of the system. Exposure of the furnace yard electrical components to overvoltages and overcurrents as a result of current harmonics, produces high electrical and mechanical stresses in the components which, if not accounted for in design, may result in failures. Operating experience with existing electric furnace installations indicates an uncharacteristically high failure rate of components which impose long time system outages and, thereby, reduce product output. A statistical 3-phase model for an arc furnace load in EMTP for time domain simulation studies will be presented. The model is first validated against field measurements and then used to examine the effect of the insertion of series reactors at the supply side of the furnace transformer on the dynamic inrush current associated with furnace transformer switching. It is shown that the insertion of a series reactor will considerably reduce the impact of furnace transformer dynamic inrush current on the filter components. The model is also used to evaluate the actual required design to withstand capabilities of the filter components. Some of the shortcomings of the conventional specifications are illustrated.

  6. 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.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission... charging intermittently every minute. b Temperature measured in off-gas channel downstream of the...

  7. 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.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission... charging intermittently every minute. b Temperature measured in off-gas channel downstream of the...

  8. 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.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4 Emission... charging intermittently every minute. b Temperature measured in off-gas channel downstream of the...

  9. 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...

  10. 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...

  11. 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...

  12. Recycling of electric arc furnace dust through dissolution in deep eutectic ionic liquids and electrowinning.

    PubMed

    Bakkar, Ashraf

    2014-09-15

    The dust waste formed during steelmaking in electric arc furnace (EAF) is rich in ferrous and nonferrous metals. Recycling of this dust as a raw material in iron or steel-making is hazardous and therefore it is mostly dumped. This paper demonstrates recycling of EAF dust through selective dissolution of metal oxides in a deep eutectic ionic liquid. It was found that about 60% of Zn and 39% of Pb could be dissolved from the dust when stirred for 48h in 1 choline chloride:2 urea ionic liquid at 60°C. The resultant electrolyte was subsequently fed to a conventional three-electrode cell where cyclic voltammetry (CV) measurements were conducted to describe its electrochemical behavior. Two deposition peaks were determined and ascribed to deposition of zinc and lead. Static potentials were successively applied to electrowin metallic zinc. SEM/EDX investigations showed that the zinc electrowon contained remarkable contents of lead. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Turning waste into valuable resource: potential of electric arc furnace dust as photocatalytic material.

    PubMed

    Sapiña, M; Jimenez-Relinque, E; Castellote, M

    2014-10-01

    This paper explores the potential of a hazardous waste of difficult management, electric arc furnace dust (EAFD), as photocatalytic material. Starting from a real waste coming from a Spanish steel factory, chemical, mineralogical, and optical characterizations have been carried out. Direct trials on EAFD and mortar containing this waste have been performed to evaluate its potential as photocatalyst itself and within a cementitious material. The analysis of photocatalytic properties has been done by two different methods: degradation of NO x and degradation of rhodamine (RhB). As a result, it can be said that EAFD exhibited photocatalytic activity for both configurations with UV and visible light, having the mortar enhanced photocatalytic activity for NO x with respect to the EAFD itself. Additionally, in direct trials on the EAFD, it has been able to degrade RhB even in the dark, which has been attributed to transfer of electrons between the adsorbed RhB and the conduction band of some oxides in the dust.

  14. Characteristics of electric arc furnaces powered by a low-frequency alternating current

    NASA Astrophysics Data System (ADS)

    Mironov, Yu. M.; Mironova, A. N.

    2016-06-01

    The changes in the parameters of a DSP-100 electric arc furnace that are induced by a decrease in the current frequency are considered. It is shown that the related decrease in the current lead resistances causes an increase in the arc power and voltage, a decrease in the reactive power, and an increase in the electrical efficiency and the power coefficient. The heat indices are expected to be significantly improved.

  15. Multivariate economic performance assessment of an MPC controlled electric arc furnace.

    PubMed

    Wei, Donghui; Craig, Ian K; Bauer, Margret

    2007-06-01

    Economic performance is very important to advanced process control projects investigating whether the investment of control technology is worthwhile. In this paper economic performance assessment of a simulated electric arc furnace is conducted. The dependence of controlled variables and the corresponding economic impact are highlighted.

  16. Valorization of electric arc furnace primary steelmaking slags for cement applications.

    PubMed

    Kim, Hyung-Seok; Kim, Kee-Seok; Jung, Sung Suk; Hwang, Jin Ill; Choi, Jae-Seok; Sohn, Il

    2015-07-01

    To produce supplementary cementitious materials from electric arc furnace (EAF) slags, FeO was reduced using a two-stage reduction process that included an Al-dross reduction reaction followed by direct carbon reduction. A decrease in FeO was observed on tapping after the first-stage reduction, and further reduction with a stirred carbon rod in the second-stage reduction resulted in final FeO content below 5wt%, which is compatible with cement clinker applications. The reduced electric arc furnace slags (REAFS) mixed with cement at a unit ratio exhibited physical properties comparable to those of commercialized ground granulated blast furnace slags (GGBFS). Confocal laser scanning microscopy (CLSM) was used to obtain fundamental information on the cooling characteristics and conditions required to obtain amorphous REAFS. REAFS can be applied in cement mixtures to achieve the hydraulic properties needed for commercial use.

  17. 75 FR 62874 - Keystone Steel and Wire Company; Grant of a Permanent Variance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-13

    ...: an electric-arc furnace, which uses an electric arc generated from electrodes to melt the scrap steel; and a ladle metallurgy furnace, which uses electrodes to maintain the molten steel at a constant... cranes to haul the scrap to the furnaces, and to transport the molten steel for further processing. Ten...

  18. Evaluation of the graphite electrode DC arc furnace for the treatment of INEL buried wastes

    SciTech Connect

    Surma, J.E.; Freeman, C.J.; Powell, T.D.; Cohn, D.R.; Smatlak, D.L.; Thomas, P.; Woskov, P.P.; Hamilton, R.A.; Titus, C.H.; Wittle, J.K.

    1993-06-01

    The past practices of DOE and its predecessor agencies in burying radioactive and hazardous wastes have left DOE with the responsibility of remediating large volumes of buried wastes and contaminated soils. The Buried Waste Integrated Demonstration (BWID), has chosen to evaluate treatment of buried wastes at the Idaho National Engineering Laboratory (INEL). Because of the characteristics of the buried wastes, the potential for using high-temperature thermal treatment technologies is being evaluated. The soil-waste mixture at INEL, when melted or vitrified, produces a glass/ceramic referred to as iron-enriched basalt (IEB). One potential problem with producing the IEB material is the high melting temperature of the waste and soil (1,400-1,600{degrees}C). One technology that has demonstrated capabilities to process high melting point materials is the plasma arc heated furnace. A three-party program was initiated and the program involved testing an engineering-scale DC arc furnace to gain preliminary operational and waste processibility information. It also included the design, fabrication, and evaluation of a second-generation, pilot-scale graphite electrode DC arc furnace. Widely ranging simulants of INEL buried waste were prepared and processed in the Mark I furnace. The tests included melting of soils with metals, sludges, combustibles, and simulated drums. Very promising results in terms of waste product quality, volume reduction, heating efficiency, and operational reliability and versatility were obtained. The results indicate that the graphite electrode DC arc technology would be very well suited for treating high melting point wastes such as those found at INEL. The graphite electrode DC arc furnace has been demonstrated to be very simple, yet effective, with excellent prospects for remote or semi-remote operation.

  19. Characterization of Submerged-Arc and Gas-Metal-Arc Weldments in HY-100 Steel.

    DTIC Science & Technology

    1983-12-01

    RD-R14i 939 CHARACTERIZATION OF SUBMERGED-ARC AND GAS-METAL-ARC / WELDMENTS IN HY-IBB STEEL (U) NAVAL POSTGRADUATE SCHOOL MONTEREY CA R E THERRIEN DEC...100 Steel 6. PIERFORMING ORG. REPORT NUM11ER I.7. AUTHOW) 11. CONTRACT OR GRANT NuMMER(.) Alfred E. Therrien _O P O R ME E E T R J C .T S’ .~ S...weld toughness in submerged arc welded (SAW) 4- HY-100 steel weldments precludes this process from large 4. scale HY-100 shipbuilding production

  20. 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.

  1. 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

    2017-06-01

    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.

  2. Gas tungsten arc and shielded metal arc welding of carbon steel to chromium-nickel steel. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-2103-ASME-1 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of carbon steels (P-1-1) to 300 series Cr-Ni steels (P-8-1), in thickness range 0.25 to 2 in.; filler metals are ERNiCr-3 (F-43) (GTAW) and ENiCrFe-3 (F-43) (SMAW); shielding gas is argon (GTAW).

  3. Solidification/stabilisation of electric arc furnace waste using low grade MgO.

    PubMed

    Cubukcuoglu, B; Ouki, S K

    2012-02-01

    This study aims to evaluate the potential of low grade MgO (LGMgO) for the stabilisation/solidification (S/S) of heavy metals in steel electric arc furnace wastes. Relevant characteristics such as setting time, unconfined compressive strength (UCS) and leaching behaviour assessed by acid neutralisation capacity (ANC), monolithic and granular leaching tests were examined in light of the UK landfill Waste Acceptance Criteria (WAC) for disposal. The results demonstrated that all studied mix designs with Portland cement type 1 (CEM1) and LGMgO, CEM1-LGMgO 1:2 and 1:4 at 40% and 70% waste addition met the WAC requirements by means of UCS, initial and final setting times and consistence. Most of the ANC results met the WAC limits where the threshold pH values without acid additions were stable and between 11.9 and 12.2 at 28d. Granular leaching results indicate fixation of most of the metals at all mix ratios. An optimum ratio was obtained at CEM1-LGMgO 1:4 at 40% waste additions where none of the metals leaching exceeded the WAC limits and hence may be considered for landfill disposal. The monolithic leaching test results showed that LGMgO performed satisfactorily with respect to S/S of Zn, as the metal component present at the highest concentration level in the waste exhibited very little leaching and passed the leaching test requirement at all mix ratios studied. However, its performance with respect to Pb, Cd and Cr was less effective in reducing their leaching suggesting a higher cumulative rate under those leaching regimes.

  4. Evaluation of the emission characteristics of PCDD/Fs from electric arc furnaces.

    PubMed

    Chang, Moo Been; Huang, Hung Chi; Tsai, Shian Sheng; Chi, Kai Hsien; Chang-Chien, Guo Ping

    2006-03-01

    Distribution of PCDD/F (polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran) congeners at two electric arc furnaces (EAFs) in Taiwan is evaluated via intensive stack sampling and analysis. Two kinds of exhaust system in EAFs including stack system and shutter system are selected for measuring dioxin emissions. In addition, dioxin emissions during oxidation and reduction stages at EAF-A were characterized. Results indicate that the PCDD/F concentration of stack gas in EAF-A was 4.39 ng/Nm(3) while total Toxic Equivalent Quantity (TEQ) concentration was 0.35 ng I-TEQ/Nm(3). The PCDD/F concentration of stack gas in EAF-B was 2.20 ng/Nm(3) and the TEQ concentration was 0.14 ng I-TEQ/Nm(3). 1,2,3,4,6,7,8-H(p)CDF, OCDD and OCDF are the major contributors of the dioxin concentrations for two EAFs investigated and the percentage of PCDD/F in particulate phase increases as the chlorination level of the PCDD/F congener increases. The results obtained on gas/particulate partitioning of PCDD/Fs in flue gases prior to the APCD in EAFs indicate that more than 90% exists in particulate phase. In EAF-A, the PCDD/F concentration during oxidation stage is slightly higher than that measured during reduction stage, including the sampling points of CO converter outlet, prior to bag filter and stack. Majority of PCDD/Fs emitted from steel-making processes exists in particulate-phase (about 60-70%) at both EAFs investigated.

  5. Submerged arc furnace process superior to the Waelz process in reducing PCDD/F emission during thermal treatment of electric arc furnace dust.

    PubMed

    Xu, Fu-Qian; Huang, Shao-Bin; Liao, Wei-Tung; Wang, Lin-Chi; Chang, Yu-Cheng; Chang-Chien, Guo-Ping

    2014-01-01

    Besides the Waelz process, the submerged arc furnace (SAF) process has also been extensively used to retain metals from ashes and scraps in the metallurgical industry. However, very little is known about the formation and depletion of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from this thermal process. In this study, an electric arc furnace (EAF) dust treatment plant adopting the SAF process was investigated and compared to the plant adopting the Waelz process. The predominant contributor of PCDD/F I-TEQ input was the EAF dusts, accounting for 98.4% of the total. The PCDD/F contents in the generated fly ashes of the SAF were extremely low, as almost all the organic compounds for PCDD/F formation were decomposed by the high operating temperatures (1500-1700 °C) of the SAF. Therefore, the PCDD/F emission factor of the SAF process (46.9 μg I-TEQ/tonne-EAF dust) was significantly lower than that of the Waelz process (840-1120 μg I-TEQ/tonne-EAF dust). Its PCDD/F output/input ratios (0.23 and 0.50 based on mass and toxicity) were also lower than those of the Waelz process plant (0.62 and 1.19). Therefore, the SAF process is superior to the Waelz process in reducing the potential of PCDD/F formation. © 2013.

  6. [Flow of high-voltage current in coal electrodes of arc furnaces as a source of noise of special nature].

    PubMed

    Polanowska, R

    1984-01-01

    The noise level for working arc furnace has been measured. Arc furnaces were found to be the source of infrasounds and acoustic field. The sound pressure levels for infrasounds range from 55 to 77 dB. It has been showed that particular noise level includes the onethird-octave band with middle frequency 100 Hz. The sound pressure levels in this band range from 105 to 110 dB.

  7. Waste form development for a DC arc furnace

    SciTech Connect

    Feng, X.; Bloomer, P.E.; Chantaraprachoom, N.; Gong, M.; Lamar, D.A.

    1996-09-01

    A laboratory crucible study was conducted to develop waste forms to treat nonradioactive simulated {sup 238}Pu heterogeneous debris waste from Savannah River, metal waste from the Idaho National Engineering Laboratory (INEL), and nominal waste also from INEL using DC arc melting. The preliminary results showed that the different waste form compositions had vastly different responses for each processing effect. The reducing condition of DC arc melting had no significant effects on the durability of some waste forms while it decreased the waste form durability from 300 to 700% for other waste forms, which resulted in the failure of some TCLP tests. The right formulations of waste can benefit from devitrification and showed an increase in durability by 40%. Some formulations showed no devitrification effects while others decreased durability by 200%. Increased waste loading also affected waste form behavior, decreasing durability for one waste, increasing durability by 240% for another, and showing no effect for the third waste. All of these responses to the processing and composition variations were dictated by the fundamental glass chemistry and can be adjusted to achieve maximal waste loading, acceptable durability, and desired processing characteristics if each waste formulation is designed for the result according to the glass chemistry.

  8. Recovering aluminum from aluminum dross in a DC electric-arc rotary furnace

    NASA Astrophysics Data System (ADS)

    Tzonev, Tz.; Lucheva, B.

    2007-11-01

    The recycling of aluminum scrap and dross yields significant economic and energy savings, as well environmental benefits. The recovery of aluminum depends on many factors. The aim of this work is to experimentally investigate aluminum recovery under different conditions. In this study, aluminum dross was processed in a direct-current electric-arc rotary furnace. The presence of crushing refractory bodies during processing was found to increase the degree of aluminum recovery by about ten percent.

  9. Optimization of ferrous burden high temperature properties to meet blast furnace requirements in British Steel

    SciTech Connect

    Bergstrand, R.

    1996-12-31

    The high temperature properties of ferrous burden materials have long been an important consideration in the operation of British Steel blast furnaces. Previous research presented at this conference has shown that the behavior of materials in the lower stack and bosh can have a significant effect on furnace permeability and stability of operation. However, with increasing levels of hydrocarbon injection via the tuyeres, the reduction conditions inside British Steel blast furnaces have significantly altered over recent years. This paper focuses on the further work that has been undertaken to study the effect on ferrous burden high temperatures properties of the widely differing reduction regimes which can be experienced in today`s blast furnaces. The implications of the findings, and how they have been used in optimizing blast furnace operation and burden quality, are discussed.

  10. 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.

  11. Profiles in garbage: Steel cans

    SciTech Connect

    Miller, C.

    1998-02-01

    Steel mills are the largest market for steel cans. Integrated mills use the basic oxygen process to manufacture tinplate, appliances, car bodies, and steel framing. Electric arc furnaces use 100% scrap to produce steel shapes such as railroad ties and bridge spans. Electric arc furnaces are more geographically diverse and tend to have smaller capacities than basic oxygen furnaces. Detinners remove the tin from steel cans for resale to tin using industries. With less tin use in steel cans, the importance of the detinning market has declined substantially. Foundries use scrap as a raw material in making castings and molds for industrial users.

  12. Research on the activating flux gas tungsten arc welding and plasma arc welding for stainless steel

    NASA Astrophysics Data System (ADS)

    Huang, Her-Yueh

    2010-10-01

    A systematic study of the effects of activating flux in the weld morphology, arc profile, and angular distortion and microstructure of two different arc welding processes, namely, Gas Tungsten Arc Welding (GTAW) and Plasma Arc Welding (PAW), was carried out. The results showed that the activating fluxes affected the penetration capability of arc welding on stainless steel. An increase in energy density resulting from the arc constriction and anode spot reduction enhanced the penetration capability. The Depth/Width (D/W) ratio of the weld played a major role in causing angular distortion of the weldment. Also, changes in the cooling rate, due to different heat source characteristics, influenced the microstructure from the fusion line to the centre of the weld.

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

    SciTech Connect

    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) 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.

  14. 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

    2017-07-01

    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.

  15. 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.

  16. Formation of hexachlorobenzene from dusts of an electric arc furnace used in steelmaking: effect of temperature and dust composition.

    PubMed

    Murakami, Taichi; Shimura, Mizuki; Kasai, Eiki

    2008-10-01

    A certain amount of hexachlorobenzene (HCB), designated a persistent organic pollutant (POP) by the Stockholm Convention, is emitted from an electric arc furnace (EAF) used in the steelmaking process. To understand the formation and decomposition behaviors of HCB during the treatment of waste gases from an EAF, characterization of dust samples from EAFs in different plants was conducted. Dusts 1 and 2 were bag filter dusts collected from a common steel plant and a special steel plant, respectively. The initial concentrations of HCB in dusts 1 and 2 were 62 and < 0.1 ng/g of dust, respectively. Then a series of heating experiments was carried out with these dust samples under various conditions. The formation of HCB from both dusts was not significant under an Ar atmosphere, although the amount of formation from dust 1 slightly increased with an increase in the holding temperature. Under an Ar--20% O2 atmosphere, however, a remarkable amount of HCB formed from dust 1 above 573 K. A certain amount of HCB was also formed from dust 2, even though the initial concentration of HCB was very low. Moreover, the coexistence of metallic compounds such as CuCl2 had a significant accelerating effect on the formation of HCB.

  17. Gas tungsten arc and shielded metal arc welding of chromium-nickel steel. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-303-ASME-3 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of 300 Series Cr-Ni steels (P-8-1), in thickness range 0.25 to 2 in.; filler metals are ER3XX (F-6, A-8) (GTAW) and E3XX-15 (F-5, A-8); shielding gas for GTAW is argon.

  18. Gas tungsten arc and shielded metal arc welding of AISI 41XX steels. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.

    1985-08-01

    Procedure WPS-127 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of AISI 4130 and 4142 steels (ASTM A519) (P-No: None), 0.438-in. wall pipe; filler metal is AMS 6457, Class 4130 MC (F-, A-No; None) (GTAW) and E8018-B2L (F-4, A-3) (GMAW); shielding gas is argon (GTAW).

  19. Gas tungsten arc and low hydrogen shielded metal arc welding of carbon steel. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-128-ASME-1 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and low hydrogen shielded metal arc welding of carbon steels (P-1-1), in thickness range 0.25 to 2 inch; filler metals are ER70S-3 (F-6, A-1) (GTAW) and E7018 (F-4, A-1); shielding gas is argon (GTAW).

  20. Manual gas tungsten arc and semiautomatic gas metal arc welding of carbon steel. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-107-ASME-1 is qualified under Section IX of the ASME Boiler and Vessel Code for manual gas tungsten arc and semiautomatic gas metal arc welding of carbon steel (P-1-1), in thickness range 0.237 to 2.0 inch; filler metal is ER70S-3 (F-6, A-1); shielding gas for GTAW is argon, and for GMAW is 95-5 argon-oxygen.

  1. Welding procedure specification: gas tungsten arc and shielded metal arc welding of carbon steel

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-104-ASME-2 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of carbon steels (P-1-1), in thickness range 0.25 to 1 in.; filler metals are E70S-3 (F-6, A-1) (GTAW) and E6010 (F-3, A-1) (SMAW); shielding gas is argon (GTAW).

  2. Elimination of harmonic induced viable bifurcations with TCSC for ac-fed electric arc furnaces

    NASA Astrophysics Data System (ADS)

    Varan, Metin; Uyarog˜lu, Yılmaz

    2012-11-01

    AC-fed electric arc furnaces (EAFs) are known with their unbalanced, excessively nonlinear and time varying load characteristics. The nonlinear oscillations produced by EAF operation cause several problems to interconnected feed system. Injection of harmonics/interharmonics and rising flicker effects on the feed system are two of major problems produced by EAF. These nonlinear effects result into quasistatic changes in the feed system parameters (L - R) . In last decade many studies have been reported that such quasistatic changes in the feed system parameters result in viable bifurcation formations which strictly cause sudden and drastic changes on system behaviors. This paper presents an analytical control procedure to eliminate viable bifurcation points on L - I and R - I curves that cause sudden resonant peak arc currents. After control procedure, stability margins of EAF are extended into larger levels and viable bifurcation points on the feed system parameter have been eliminated. During study, possible roles of small parameter changes of uncontrolled EAF around bifurcation points and controlled EAF have been traced over time series analysis, phase plane analysis and bifurcation diagrams. A wide collection of useful dynamic analysis procedures for the exploration of studied arc furnace dynamics have been handled through the AUTO open-source algorithms.

  3. 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

  4. Updating the Mode of Annealing of Tubes from Steel ShKh15 in Chamber Furnaces

    NASA Astrophysics Data System (ADS)

    Yur'ev, B. P.; Gol'tsev, V. A.

    2016-11-01

    A study of commercial tubes from steel ShKh15 produced in a chamber furnace is performed for investigating the active annealing process. The causes of inappropriate heating and cooling of tubes in a charge are determined. The annealing mode is shown to mismatch the required temperature regime, which elevates rejection. Recommendations for eliminating the determined drawbacks, raising the quality of the annealed tubes and the output of the chamber furnaces are developed.

  5. 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.

  6. Method for processing aluminum spent potliner in a graphite electrode arc furnace

    DOEpatents

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

    2002-12-24

    A method of processing spent aluminum pot liner containing carbon, cyanide compositions, fluorides and inorganic oxides. The spend 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.

  7. Steelworks residues and the Waelz kiln treatment of electric arc furnace dust

    SciTech Connect

    Strohmeier, G.; Bonestell, J.E.

    1996-04-01

    Electric arc furnace dust with a combined zinc and lead content in excess of 20% renders the dumping of this material impossible in many countries, for both statutory and financial reasons. In the Waelz process, dust is treated in a rotary kiln where it is heated to approximately 1,200 C. lead and zinc are volatilized under reducing conditions and collected as fine dust in the off-gas dust collection system. The oxide recovered in the off-gas filters contains approximately 55% Zn and up to 10% Pb, and is ideal feedstock for the Imperial Smelting furnace for lead/zinc recovery. The remaining slag is inert and unleachable so that it can be used as a building aggregate.

  8. Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia.

    PubMed

    Mohiuddin, Kazi; Strezov, Vladimir; Nelson, Peter F; Stelcer, Eduard; Evans, Tim

    2014-07-15

    The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 μm. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings.

  9. Chemical, physical, structural and morphological characterization of the electric arc furnace dust.

    PubMed

    Machado, Janaína G M S; Brehm, Feliciane Andrade; Moraes, Carlos Alberto Mendes; Santos, Carlos Alberto Dos; Vilela, Antônio Cezar Faria; Cunha, João Batista Marimon da

    2006-08-25

    Electric arc furnace dust (EAFD) is a hazardous industrial waste generated in the collection of particulate material during steelmaking process via electric arc furnace. Important elements to the industry such as, Fe and Zn are the main ones in EAFD. Due to their presence, it becomes very important to know how these elements are combined before studying new technologies for its processing. The aim of this work was to carry out a chemical, physical, structural and morphological characterization of the EAFD. The investigation was carried out by using granulometry analysis, chemical analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy via SEM (EDS), X-ray mapping analysis via SEM, X-ray diffraction (XRD) and Mössbauer spectroscopy. By XRD the following phases were detected: ZnFe(2)O(4), Fe(3)O(4), MgFe(2)O(4), FeCr(2)O (4), Ca(0.15)Fe(2.85)O(4), MgO, Mn(3)O(4), SiO(2) and ZnO. On the other hand, the phases detected by Mössbauer spectroscopy were: ZnFe(2)O(4), Fe(3)O(4), Ca(0.15)Fe(2.85)O(4) and FeCr(2)O(4). Magnesium ferrite (MgFe(2)O(4)), observed in the XRD pattern as overlapped peaks, was not identified in the Mössbauer spectroscopy analysis.

  10. Modeling of Linear Gas Tungsten Arc Welding of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Maran, P.; Sornakumar, T.; Sundararajan, T.

    2008-08-01

    A heat and fluid flow model has been developed to solve the gas tungsten arc (GTA) linear welding problem for austenitic stainless steel. The moving heat source problem associated with the electrode traverse has been simplified into an equivalent two-dimensional (2-D) transient problem. The torch residence time has been calculated from the arc diameter and torch speed. The mathematical formulation considers buoyancy, electromagnetic induction, and surface tension forces. The governing equations have been solved by the finite volume method. The temperature and velocity fields have been determined. The theoretical predictions for weld bead geometry are in good agreement with experimental measurements.

  11. Waste product profile: Steel cans

    SciTech Connect

    Miller, C.

    1996-07-01

    Steel cans are made from tinplate steel, which is produced in basic oxygen furnaces. A thin layer of tin is applied to the can`s inner and outer surfaces to prevent rusting and protect food and beverage flavors. As a result, steel cans are often called tin cans. Steel mills are the largest market for steel cans. Integrated mills use the basic oxygen process to manufacture tinplate, appliances, car bodies, and steel framing. Electric arc furnaces use 100% scrap to produce steel shapes such as railroad ties and bridge spans. Electric arc furnaces are more geographically diverse and tend to have smaller capacities than basic oxygen furnaces. Detinners remove the tin from steel cans for resale to tin using industries. Continued decreases in the amount of tin used in steel cans has lessened the importance of this market. Foundries use scrap as a raw material in making castings and molds for industrial users.

  12. Combustion Modifications of Batch Annealing Furnaces and Ammonia Combustion Ovens for NOX Abatement in Steel Plants.

    PubMed

    Teng, Hsisheng

    1996-12-01

    NOX control employing several combustion modification techniques is studied in batch annealing furnaces and ammonia combustion ovens in steel plants. The fuels of the annealing furnace and ammonia oven are by-product fuel gases and ammonia vapor, respectively, which are generated in the same steelworks. Study of the emission characteristics of the annealing furnace show that delayed combustion can effectively reduce NOX emissions. Delayed combustion is accomplished by air-staging in burners, off-symmetric mixing of fuel and air, and air-biasing in the furnace, and these modification can operations achieve 60%, 40%, and 26% of NOX reductions, respectively. For the ammonia oven, NOX emission from combustion of ammonia vapor is remarkably reduced by staging the air injected into the oven, adjusting the total air rate, and adding by-product fuel gases to the combustion system.

  13. Modern trends in improvement of steel heating technology in continuous furnaces

    NASA Astrophysics Data System (ADS)

    Timoshpolskiy, V. I.; Temlyantsev, M. V.; Trusova, I. A.

    2016-09-01

    The principles and approaches in the development and improvement of steel heating technology in the furnaces of rolling manufacture of various structural design, based on the systematic study of thermal physical and technological processes, including mathematical modeling, industrial experiments, development of rational temperature-thermal modes.

  14. 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.

  15. Occupational asthma due to gas metal arc welding on mild steel.

    PubMed Central

    Vandenplas, O.; Dargent, F.; Auverdin, J. J.; Boulanger, J.; Bossiroy, J. M.; Roosels, D.; Vande Weyer, R.

    1995-01-01

    Occupational asthma has been documented in electric arc welders exposed to manual metal arc welding on stainless steel. A subject is described who developed late and dual asthmatic reactions after occupational-type challenge exposure to gas metal arc welding on uncoated mild steel. PMID:7597679

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

    PubMed

    Witek, Jerzy; Kusiorowski, Robert

    2017-08-12

    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.

  17. Reduction Kinetics of Electric Arc Furnace Oxidizing Slag by Al-Fe Alloy

    NASA Astrophysics Data System (ADS)

    Lee, Jaehong; Oh, Joon Seok; Lee, Joonho

    2016-09-01

    Effects of temperature and slag basicity on the reduction rate of iron oxide in molten synthetic electric arc furnace oxidizing slag by Al-40 wt.%Fe alloy was investigated. An alloy sample was dropped into molten slag in an MgO crucible. When the initial slag temperature was 1723 K, there was no reduction. However, when the initial slag temperature was 1773 K and the slag basicity was 1.1, the reduction was initiated and the temperature of the slag rapidly increased. When the slag basicity was 1.1, increasing the initial slag temperature from 1773 K to 1823 K increases the reaction rate. As the slag basicity increased from 1.1 to 1.4 at 1773 K, the reaction rate increased. From SEM analysis, it was found that an Al2O3 or a spinel phase at the slag-metal interface inhibited the reaction at a lower temperature and a lower slag basicity.

  18. Optimization of a Steel Plant with Multiple Blast Furnaces Under Biomass Injection

    NASA Astrophysics Data System (ADS)

    Wiklund, Carl-Mikael; Pettersson, Frank; Saxén, Henrik

    2013-04-01

    The allocation of resources between several blast furnaces in an integrated steelmaking plant is studied with the aim of finding the lowest specific operation cost for steel production. In order to reduce the use of fossil fuels, biomass was considered as an auxiliary reductant in the furnace after partial pyrolysis in an external unit, as a complement to heavy fuel oil. The optimization considers raw material, energy, and emission costs and a possible credit for sold power and heat. To decrease computational requirements and to guarantee that the global optimum is found, a piecewise linearized model of the blast furnace was used in combination with linear models of the sinter-, coke-, and power plants, hot stoves, and basic oxygen furnace. The optimization was carried out under different constraints on the availability of some raw materials as well as for different efficiencies of the hot stoves of the blast furnaces. The results indicate that a non-uniform distribution of the production between the furnaces can be advantageous, and some surprising findings concerning the optimal resource allocation under constrained operation are reported.

  19. Thermodynamic analysis of the selective carbothermic reduction of electric arc furnace dust.

    PubMed

    Pickles, C A

    2008-01-31

    Electric arc furnace (EAF) dust, which is produced as a result of the melting of automobile scrap in an electric arc furnace, contains considerable amounts of zinc and lead, which are of significant economic value. Typically, the other major components are iron oxide and calcium oxide with minor amounts of other metal oxides. In this research, a detailed thermodynamic study of the pyrometallurgical processing of the dust, using carbon as a reducing agent was performed. The SOLGASMIX solver of Outokumpu HSC Chemistry((R)) 5.1 was used to calculate the equilibrium composition under reducing conditions. The control input dust composition was as follows (in mass percent): 8.100% CaO, 8.250% 2CaO.SiO(2), 11.200% CaCO(3), 8.830% CaO.Fe(2)O(3), 7.840% Fe(3)O(4), 3.770% PbO, 38.150% ZnFe(2)O(4) and 13.860% ZnO. Selective reduction and separation of both the zinc and the lead as metallic vapours, from the iron, in oxide form, was examined. The separation of the zinc or the lead from the iron, was defined quantitatively in terms of the selectivity factor (logbeta) as follows. Equation [see the text] where the subscript symbols refer to the metal being present in gaseous (g), metallic solid (m), solid oxide (o) or metallic liquid (l) form, respectively. The standard calculations were performed for one hundred grams of dust at atmospheric pressure. The variables investigated were as follows; temperature in the range of 1273-1873K, reactant ratio (i.e. moles of carbon per gram of dust), dust composition, addition of inert gas and reduced total pressure. The calculated values were in reasonable agreement with those from previously published studies and also industrial results.

  20. Laboratory experiments on arc deflection and instability

    SciTech Connect

    Zweben, S.; Karasik, M.

    2000-03-21

    This article describes experiments on arc deflection instability carried out during the past few years at the Princeton University Plasma Physics Laboratory (PPPL). The approach has been that of plasma physicists interested in arcs, but they believe these results may be useful to engineers who are responsible for controlling arc behavior in large electric steel furnaces.

  1. A Feasibility Study on Low Temperature Thermochemical Treatments of Austenitic Stainless Steel in Fluidized Bed Furnace

    NASA Astrophysics Data System (ADS)

    Haruman, Esa; Sun, Yong; Triwiyanto, Askar; Manurung, Yupiter H. P.; Adesta, Erry Y.

    2011-04-01

    In this work, the feasibility of using an industrial fluidized bed furnace to perform low temperature thermochemical treatments of austenitic stainless steels has been studied, with the aim to produce expanded austenite layers with combined wear and corrosion resistance, similar to those achievable by plasma and gaseous processes. Several low temperature thermochemical treatments were studied, including nitriding, carburizing, combined nitridingcarburizing (hybrid treatment), and sequential carburizing and nitriding. The results demonstrate that it is feasible to produce expanded austenite layers on the investigated austenitic stainless steel by the fluidized bed heat treatment technique, thus widening the application window for the novel low temperature processes. The results also demonstrate that the fluidized bed furnace is the most effective for performing the hybrid treatment, which involves the simultaneous incorporation of nitrogen and carbon together into the surface region of the component in nitrogen and carbon containing atmospheres. Such hybrid treatment produces a thicker and harder layer than the other three processes investigated.

  2. 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).

  3. 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.

  4. Behavior of Zn and Fe Content in Electric Arc Furnace Dust as Submitted to Chlorination Methods

    NASA Astrophysics Data System (ADS)

    Santos, Felipe; Brocchi, Eduardo; Araújo, Victor; Souza, Rodrigo

    2015-08-01

    This work covers initially a general thermodynamics assessment regarding the zinc ferrite (ZnFe2O4) behavior toward direct and reducing chlorination. Then, the use of alternative chlorination agents were also theoretically appreciated, before a set of experiments has been carried out with industrial residue (electric arc furnace dust). Besides identifying zinc ferrite (95.4 pct), the XRD analysis indicated the presence of ZnO (4.6 pct). Therefore, the main objective of the present work is related to a theoretical (thermodynamics) and experimental (kinetics) evaluation of the mentioned residue chemical behavior as submitted to chlorination methods. Several characterization methods were used, such as X-ray diffraction, scanning electron microscopy, X-ray fluorescence, mass spectroscopy (ICP-MS), and energy-dispersive X-ray spectroscopy (EDS). It was observed that zinc was present, mostly, in the form of zinc ferrite (franklinite). The thermodynamics study revealed that Zn has a more susceptible behavior regarding the oxides conversion into chlorides. However, this tendency is not necessarily associated with a selective reaction, as showed for the chlorination in the presence of carbon, as both iron and zinc chlorides formation is feasible. The experimental results have indicated that some reaction systems can be further studied in order to identify operational conditions that enable selective formations. So, it was observed that for the calcium chloride reaction conducted at 1273 K (1000 °C) for 30 minutes, the iron content in the residue slightly increases (with 15 pct removal), whereas the zinc content decreases from 20 to 12 pct (53 pct removal), suggesting complementary studies where this possible selectivity could be even more determinant. Such results have also indicated that the direct action of chlorine at 1073 K (800 °C) allowed complete removal of zinc, followed by conversion in the order of 40 pct in iron. Therefore, a complementary investigation over

  5. 75 FR 38130 - Keystone Steel and Wire Company; Notice of Application for a Permanent Variance, Grant of an...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... the melting process consists of: An electric-arc furnace, which uses an electric arc generated from electrodes to melt the scrap steel; and a ladle metallurgy furnace, which uses electrodes to maintain the... requires the use of two overhead cranes to haul the scrap to the furnaces, and to transport the molten...

  6. Hydrometallurgical process for zinc recovery from electric arc furnace dust (EAFD): part I: Characterization and leaching by diluted sulphuric acid.

    PubMed

    Oustadakis, P; Tsakiridis, P E; Katsiapi, A; Agatzini-Leonardou, S

    2010-07-15

    The present paper is the first of a series of two articles dealing with the development of an integrated process for the recovery of zinc from electric arc furnace dust (EAFD), a hazardous industrial waste generated in the collection of particulate material during steelmaking process via electric arc furnace. Part I presents the EAFD characterization and its leaching process by diluted sulphuric acid, whereas Part II deals with the purification of the leach liquor and the recovery of zinc by solvent extraction/electrowinning. The characterization of the examined electric arc furnace dust was carried out by using granulometry analysis, chemical analysis, X-ray diffraction (XRD), thermogravimetric/differential thermal analysis (TG/DTA) and scanning electron microscopy (SEM). The leaching process was based on the Zn extraction with diluted sulphuric acid from EAFD under atmospheric conditions and without using any preliminary treatment. Statistical design and analysis of experiments were used, in order to determine the main effects and interactions of the leaching process factors, which were: acid normality, temperature and solid to liquid ratio. The zinc recovery efficiency on the basis of EAFD weight reached 80%. X-ray diffraction and scanning electron microscopy were used for the characterization of the leached residues.

  7. 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.

  8. Hydrometallurgical recovery of zinc and lead from electric arc furnace dust using mononitrilotriacetate anion and hexahydrated ferric chloride.

    PubMed

    Leclerc, Nathalie; Meux, Eric; Lecuire, Jean Marie

    2002-04-26

    The purpose of this work was to study the feasibility at laboratory-scale of a new hydrometallurgical process for treating electric arc furnace dusts (EAFD). The proposed process is intended to extract zinc and lead from EAFD without destroying the iron oxides matrix. So, this material can be recycled by the steel industry. Independently of the origin of the samples, major mineralogical forms present in these wastes are Fe3O4, ZnO, ZnFe2O4 and PbOHCl. The proposed process consists of a hydrometallurgical treatment of wastes based on selective leaching of zinc and lead. Initially, a leaching is carried out utilizing a chelating agent, nitrilotriacetate anion (NTA3-), as the protonated form HNTA2-. Treatment of five EAFD samples for an hour at room temperature with a molar solution of reagent results in total leaching of the ZnO. In all cases the solubilized iron does not exceed 3 wt.%. The recovery of zinc and lead is performed by precipitation of metallic sulfides with a solution of Na2S4 sodium tetrasulfide 2M. These metallic sulfides can be used as metallurgical raw materials and the chelating reagent can be reused in the process after pH adjustment. The results of the normalized leaching test AFNOR X31-210 conducted on the leaching residues, shows that all the samples meet acceptance thresholds for hazardous wastes landfill. However, the residues contain a considerable amount of zinc as ZnFe2O4. The extraction of the zinc element requires the destruction of the ferrite structure. In this process, ZnFe2O4 is treated by FeCl3.6H2O. The reaction consists in a particle O2-/Cl- exchange allowing the recovery of zinc as ZnCl2 and iron as hematite Fe2O3. The separation of these products is accomplished by simple aqueous leaching. All of the zinc is extracted in a 8h treatment at 150 degrees C with a molar ratio FeCl3.6H2O/ZnFe2O4 equal to 10. Ultimate solid residues, which have been concentrated in iron, can be oriented towards the steel industry.

  9. Leaching properties of electric arc furnace dust prior/following alkaline extraction.

    PubMed

    Orescanin, Visnja; Mikelić, Luka; Sofilić, Tahir; Rastovcan-Mioc, Alenka; Uzarević, Krunoslav; Medunić, Gordana; Elez, Loris; Lulić, Stipe

    2007-02-15

    This study was carried out to determine the appropriate treatment of electric arc furnace (EAF) dust prior to permanent disposal. The total heavy metal content as well as heavy metal leaching from EAF dust was investigated in five composite samples obtained from three Croatian and Slovenian steelworks. In order to recover zinc and reduce its leaching from the dust, all five samples were submitted to alkaline extraction with 10 M NaOH. Reduction of Cr (VI) to Cr(III) was conducted using FeSO4 x 7H2O solution. The elements Mn, Fe, Cu, Ni, and notably Zn and Pb, exhibited highest mobility during toxicity characteristic leaching procedure (TCLP). Comparing to TCLP extracts of initial EAF dust, zinc was found to be over 15 times lower and lead over 200 times lower in TCLP extracts of EAF dust processed by the alkaline leaching method. Since Cr (VI) exceeded its permissible level in the DIN 38414-S4 extracts of both initial and alkaline digested dust, its reduction to Cr (III) prior to permanent disposal is necessary. The recovery of zinc from EAF dust treated with alkaline agent ranged from 50.3% to 73.2%. According to phase analysis, recovery yield showed dependence on zincite/franklinite ratio. The results of the study indicate that permanent disposal of EAF dust require the following procedure: alkaline digestion (followed by leachate purification and alkaline zinc electrolyses), chromate reduction (if necessary), solidification of leaching residue and its testing using the leaching analyses.

  10. Electric arc furnace dust as an alternative low-cost oxygen carrier for chemical looping combustion.

    PubMed

    Kuo, Yu-Lin; Huang, Wei-Chen; Tseng, Yao-Hsuan; Chang, Shu-Huai; Ku, Young; Lee, Hao-Yeh

    2017-08-12

    The relative abundance and low cost of electric arc furnace dust (EAFD) make it a viable oxygen carrier for chemical looping combustion (CLC) system. Under a reducing agent, zinc ferrite (ZnFe2O4) phase in EAFD releases zinc vapor in a complex gas-solid reaction. In an effort to suppress the emission of zinc vapor, the reaction mechanism of ZnFe2O4 prepared as an oxygen carrier in a redox cycling test is primarily discussed, as well as the issue of coupling with an inert Al2O3 support. The study focused the investigation on redox cycling behavior and CO2 conversion in ZnFe2O4/Al2O3 and EAFD/Al2O3 systems using a thermogravimetric analyzer (TGA) and fixed-bed reactor (FxBR). In a lab-scaled semi-fluidized bed reactor (semi-FzBR) of EAFD/Al2O3 as an oxygen carrier system, a high CO gas yield approximately 0.98 after fifty redox cycles is also experimentally obtained. It can be anticipated that the use of EAFD/Al2O3 system as an oxygen carrier in a reversible CLC process could be economical and environmentally beneficial. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Review of Innovative Energy Savings Technology for the Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Lee, Baek; Sohn, Il

    2014-09-01

    A review of the energy innovations for the electric arc furnace (EAF) steelmaking route is discussed. Preheating of scrap using vertical and horizontal shafts that have been commercially successful in lowering the energy consumption to as much as 90 kWh/t reaching almost the operational limit to heating input scrap materials into the EAF is discussed. Bucket-type and twin-shell preheaters have also shown to be effective in lowering the overall power consumption by 60 kWh/t, but these have been less effective than the vertical shaft-type preheaters. Beyond the scrap preheating technologies, the utilization of waste heat of the slags from the laboratory scale to the pilot scale has shown possible implementation of a granulation and subsequent heat exchange with forced air for energy recovery from the hot slags. Novel techniques to increase metal recovery have shown that laboratory-scale testing of localized Fe concentration into the primary spinel crystals was possible allowing the separation of an Fe-rich crystal from an Fe-depleted amorphous phase. A possible future process for converting the thermal energy of the CO/CO2 off-gases from the EAF into chemical energy was introduced.

  12. 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 (CaZn2(OH)6·2H2O) 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.

  13. Integrated hydrometallurgical process for production of zinc from electric arc furnace dust in alkaline medium.

    PubMed

    Youcai, Z; Stanforth, R

    2000-12-30

    In this study, a novel and integrated hydrometallurgical process for the production of zinc powder from electric arc furnace (EAF) dust in alkaline medium is reported. The dust is firstly hydrolysed in water, and then fused in caustic soda at 350 degrees C for 1h, followed by leaching in alkaline solution in which both zinc and lead are effectively extracted. Zinc powder is then produced by electrowinning from the leach solution after the lead is selectively removed by precipitation using sodium sulphide as precipitant. The EAF dust tested contained 25% Zn, 1.8% Pb and 33% Fe. It was found that 38% of zinc and 68% of lead could be extracted from the dust when leached directly in caustic soda solution. Leaching of zinc increased to 80% when dust was directly fused with caustic soda followed by alkaline leaching. However, the leaching further increased to 95% when the dust was hydrolysed first with water before fusion. Zinc powder with a purity of 99.95% was then produced by electrowinning from the lead depleted solution. Stainless electrodes were used as both anode and cathode.

  14. Recovery of Zn from acid mine water and electric arc furnace dust in an integrated process.

    PubMed

    Carranza, Francisco; Romero, Rafael; Mazuelos, Alfonso; Iglesias, Nieves

    2016-01-01

    In this paper, the purification of acid mine water and the treatment of electric arc furnace dust (EAFD) are integrated into one process with the aim of recovering the Zn content of both effluent and waste. Zinc recovery can reduce the cost of their environmental management: purified acid mine water is discharged after removing all metals; EAFD ceases to be hazardous waste; and Zn is valorised. The process consists of the recovery of Zn as zinc oxide and its purification into commercial products. First, EAFD is leached with acid water and the dissolved metals are selectively precipitated as hydroxides. After EADF leaching, ferrous iron is bio-oxidized and Fe and Al are then precipitated; in the following stage, Cu, Ni, Co and Cd are cemented and finally Zn is precipitated as ZnO. In order to purify water that finally is discharged to a river, lime is used as the neutralizing agent, which results in a precipitate of mainly gypsum, MnO, and ZnO. From the impure zinc oxide produced, various alternatives for the attainment of commercial products, such as basic zinc carbonate and electrolytic zinc, are studied in this work. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Microwave treatment of electric arc furnace dust with PVC: dielectric characterization and pyrolysis-leaching.

    PubMed

    Al-Harahsheh, Mohammad; Kingman, Sam; Al-Makhadmah, Leema; Hamilton, Ian E

    2014-06-15

    Microwave treatment of electric arc furnace dust (EAFD) with poly(vinyl chloride) (PVC) was studied in this work. A comprehensive characterization of the dust as well as assessing the suitability of using the thermal de-chlorination of the common plastic (PVC) under inert atmosphere was carried out to assess the possibility of Zn and other heavy metals extraction (Pb and Cd) from EAFD. The dielectric and thermal properties of EAFD, PVC and their mixtures were measured. Once combined and heated the metal oxides present in the dust reacted with HCl released from PVC during thermal de-chlorination, forming metal chlorides which were subsequently recovered by leaching with water. It was found that zinc chloride could be almost completely recovered in the leaching stage, with the overall recovery of Zn reaching 97% when the EAFD:PVC ratio was 1:2. The investigation highlighted that franklinite, the most refractory mineral to leaching, was completely destroyed. The leaching residue was found to compose mainly of magnetite and hematite. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. 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.

  17. 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

  18. 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.

  19. Analysis of uranium-bearing Fe-phosphide from a submerged arc furnace for phosphorus production

    NASA Astrophysics Data System (ADS)

    Voncken, J. H. L.; Scheepers, E.; Yang, Y.

    2006-10-01

    During a study on the Fe-phosphide phase formed during phosphorus production in a submerged arc furnace, a sample of ferrophosphorus was found which contains a so far unknown uranium-bearing Fe-phosphide. Uranium, as well as other trace metals like Mn, V, Cr, Ni, Zr, originates from the apatite ore used. Ti originates partly from the silica and coke used in the reduction process, but mainly from the clay used to produce ore pellets. In this paper the ferrophosphorus is described with respect to composition and crystalline compounds present. The crystallization sequence is discussed with respect to the FeP-phase diagram. The main phases found in the ferrophosphorus are FeP and Fe2P. With respect to trace and minor metals, it is observed that Si preferably enters the FeP-phase, whereas Ti, V, Cr, Mn and Ni preferably enter the Fe2P-phase, which is an analogue of the mineral barringerite. This study gives some insight into the behavior of impurities during crystallization of an iron-rich Fe-phosphide melt. The uranium-bearing phase has an overall Me2P-stoichiometry (Fe1.59, Ti0.06, V0.03, Cr0.02, Mn0.06, Ni0.02, U0.15, Zr0.09)2.02 (P0.96, Si0.02)0.98. An X-ray diffraction pattern of this phase is given for identification purposes.

  20. 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.

  1. Mathematical Model for Decarburization of Ultra-low Carbon Steel in Single Snorkel Refining Furnace

    NASA Astrophysics Data System (ADS)

    You, Zhimin; Cheng, Guoguang; Wang, Xinchao; Qin, Zhe; Tian, Jun; Zhang, Jian

    2014-09-01

    A dynamic model is developed to investigate decarburization behavior of a new type of refining equipment named Single Snorkel Refining Furnace (SSRF) in treating ultra-low carbon steel. Decarburization reactions in SSRF are considered to take place at three sites: Ar bubble surface, the bulk steel, and the bath surface. With the eccentricity of the porous plug (r e/R S) and the ratio of the snorkel diameter to the ladle diameter (D S/D L) of SSRF confirmed, circulation flow rate of molten steel is obtained through combined effects of vacuum pressure and gas flow rate. Besides, variation of the steel temperature is simulated associated with generated reaction heat and heat losses. The variation of C concentration with treatment time is divided into three stages in accordance with decarburization rates and the simulated C concentration is in reasonable agreement with actual production data. In the present study, both decarburization rates at three sites and their contributions to the overall decarburization at each stage are estimated for the first time. Through the present investigation, it is clear that vacuum pressure significantly influences decarburization efficiency of SSRF primarily by affecting the depth of CO nucleation in the bulk steel. Besides, effects of gas flow rate on decarburization rate of different stages are obtained and the opportunity of increasing gas flow rate during the treatment period has been clarified. The present model provides an efficient tool to comprehend the decarburization process in SSRF.

  2. Mathematical Model for Decarburization of Ultra-low Carbon Steel in Single Snorkel Refining Furnace

    NASA Astrophysics Data System (ADS)

    You, Zhimin; Cheng, Guoguang; Wang, Xinchao; Qin, Zhe; Tian, Jun; Zhang, Jian

    2015-02-01

    A dynamic model is developed to investigate decarburization behavior of a new type of refining equipment named Single Snorkel Refining Furnace (SSRF) in treating ultra-low carbon steel. Decarburization reactions in SSRF are considered to take place at three sites: Ar bubble surface, the bulk steel, and the bath surface. With the eccentricity of the porous plug ( r e/ R S) and the ratio of the snorkel diameter to the ladle diameter ( D S/ D L) of SSRF confirmed, circulation flow rate of molten steel is obtained through combined effects of vacuum pressure and gas flow rate. Besides, variation of the steel temperature is simulated associated with generated reaction heat and heat losses. The variation of C concentration with treatment time is divided into three stages in accordance with decarburization rates and the simulated C concentration is in reasonable agreement with actual production data. In the present study, both decarburization rates at three sites and their contributions to the overall decarburization at each stage are estimated for the first time. Through the present investigation, it is clear that vacuum pressure significantly influences decarburization efficiency of SSRF primarily by affecting the depth of CO nucleation in the bulk steel. Besides, effects of gas flow rate on decarburization rate of different stages are obtained and the opportunity of increasing gas flow rate during the treatment period has been clarified. The present model provides an efficient tool to comprehend the decarburization process in SSRF.

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

    SciTech Connect

    Nimbalkar, Sachin U; Thekdi, Arvind; Keiser, James R; Storey, John Morse

    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 which 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.

  4. Long and short-term performance of a stabilized/solidified electric arc furnace dust.

    PubMed

    Pereira, C Fernández; Galiano, Y Luna; Rodríguez-Piñero, M A; Parapar, J Vale

    2007-09-30

    The application of class F fly ash, cement and lime to the Stabilization/Solidification (S/S) of electric arc furnace dust containing hazardous metals such as Zn, Pb, Cd, and Cr is described. The aim of the study was to determine the influence of the setting conditions during the S/S treatment and to know the behaviour of an aged solidified and stabilized waste. In order to determine the efficiency attained by the S/S process, USEPA TCLP, and other leaching tests have been accomplished. In addition, the compressive strength of the solidified waste at different times has been determined. In order to study the influence of the environmental conditions in which setting occurs, experiments were carried out with samples of the same composition, under different setting conditions: laboratory environment, stove at a temperature of 40-60 degrees C and setting in a hermetically sealed plastic bag at room temperature. All the samples were subjected to the TCLP test at 28 days, and the metal content of the resulting leachates was analysed. The results show that in some cases the setting conditions of the mixtures have a noticeable influence on the characteristics of the leachate. The evolution with time of some S/S solids, one month after their manufacture and more than 9 years after that has also been evaluated, by means of their leaching behaviour. The results obtained in this work have shown, in all the laboratory cured samples that the leachate pH decrease in the course of time, and consequently the leaching behaviour is in general worse. This could be due to the carbonation of the S/S solid and the subsequent loss of alkalinity.

  5. Identification and characterization of the atmospheric emission of polychlorinated naphthalenes from electric arc furnaces.

    PubMed

    Liu, Guorui; Zheng, Minghui; Du, Bing; Nie, Zhiqiang; Zhang, Bing; Hu, Jicheng; Xiao, Ke

    2012-09-01

    Electric arc furnaces (EAF) are well recognized as significant sources of dioxins. EAFs have also been speculated to be sources of polychlorinated naphthalenes (PCNs) due to the close correlation between dioxin and PCN formation. However, assessment on PCN emissions from EAFs has not been carried out. The primary aim of this preliminary study is to identify and characterize the atmospheric emission of PCNs from EAFs. In this preliminary study, stack gas samples from two typical EAFs with different scales (EAF-1, 160 t batch(-1); and EAF-2, 60 t batch(-1)) were collected by automatic isokinetic sampling technique, and PCN congeners in samples were analyzed by isotope dilution high-resolution gas chromatography combined with high-resolution mass spectrometry method. Emission concentrations of PCNs were 458 and 1,099 ng m(-3) for EAF-1 and EAF-2, respectively. The emission factors of PCNs to air were 21.6 and 30.1 ng toxic equivalent t(-1) for EAF-1 and EAF-2, respectively, which suggested that EAF is an important source of PCN release. With regard to the characteristics of PCNs from EAFs, lower chlorinated homologues were dominant. The PCN congeners comprised of CN27/30, CN52/60, CN66/67, and CN73 were the most abundant congeners for tetra-, penta-, hexa-, and hepta-chlorinated homologues, respectively. EAFs were identified to be an important PCN source, and the obtained data are useful for developing a PCN inventory. The congener profiles of PCNs presented here might provide helpful information for identifying the specific sources of PCNs emitted from EAFs.

  6. Recycling of rubber tires in electric arc furnace steelmaking: simultaneous combustion of metallurgical coke and rubber tyres blends

    SciTech Connect

    Magdalena Zaharia; Veena Sahajwalla; Byong-Chul Kim; Rita Khanna; N. Saha-Chaudhury; Paul O'Kane; Jonathan Dicker; Catherine Skidmore; David Knights

    2009-05-15

    The present study investigates the effect of addition of waste rubber tires on the combustion behavior of its blends with coke for carbon injection in electric arc furnace steelmaking. Waste rubber tires were mixed in different proportions with metallurgical coke (MC) (10:90, 20:80, 30:70) for combustion and pyrolysis at 1473 K in a drop tube furnace (DTF) and thermogravimetric analyzer (TGA), respectively. Under experimental conditions most of the rubber blends indicated higher combustion efficiencies compared to those of the constituent coke. In the early stage of combustion the weight loss rate of the blends is much faster compared to that of the raw coke due to the higher volatile yield of rubber. The presence of rubber in the blends may have had an impact upon the structure during the release and combustion of their high volatile matter (VM) and hence increased char burnout. Measurements of micropore surface area and bulk density of the chars collected after combustion support the higher combustion efficiency of the blends in comparison to coke alone. The surface morphology of the 30% rubber blend revealed pores in the residual char that might be attributed to volatile evolution during high temperature reaction in oxygen atmosphere. Physical properties and VM appear to have a major effect upon the measured combustion efficiency of rubber blends. The study demonstrates that waste rubber tires can be successfully co-injected with metallurgical coke in electric arc furnace steelmaking process to provide additional energy from combustion. 44 refs., 11 figs., 2 tabs.

  7. 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.

  8. Manual gas tungsten arc and semiautomatic gas metal arc welding of chromium-nickel steel. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-306-ASME-6 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for manual gas tungsten arc and semiautomatic gas metal arc welding of 300 Series Cr-Ni steels (P-8-1), in thickness range 0.375 to 2 inch; filler metal is ER3XX (F-6, A-8); shielding gases are argon (GTAW) and 98-2 argon-oxygen.

  9. Machine gas tungsten arc and machine gas metal arc welding of chromium-nickel steel. Welding procedure specification

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1985-08-01

    Procedure WPS-309-ASME-0 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for machine gas tungsten arc and machine gas metal arc welding of 300 Series Cr-Ni steels (P-8-1), in thickness range 0.375 to 2 inch; filler metal is ER3XX (F-6,A-8); shielding gases are argon (GTAW) and 98-2 argon-oxygen (GMAW).

  10. 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.

  11. An Investigation on Low-Temperature Thermochemical Treatments of Austenitic Stainless Steel in Fluidized Bed Furnace

    NASA Astrophysics Data System (ADS)

    Haruman, E.; Sun, Y.; Triwiyanto, A.; Manurung, Y. H. P.; Adesta, E. Y.

    2012-03-01

    In this study, the feasibility of using an industrial fluidized bed furnace to perform low-temperature thermochemical treatments of austenitic stainless steels has been studied, with the aim to produce expanded austenite layers with combined wear and corrosion resistance, similar to those achievable by plasma and gaseous processes. Several low-temperature thermochemical treatments were studied, including nitriding, carburizing, combined nitriding-carburizing (hybrid treatment), and sequential carburizing and nitriding. The results demonstrate that it is feasible to produce expanded austenite layers on the investigated austenitic stainless steel by the fluidized bed heat treatment technique, thus widening the application window for the novel low-temperature processes. The results also demonstrate that the fluidized bed furnace is the most effective for performing the hybrid treatment, which involves the simultaneous incorporation of nitrogen and carbon together into the surface region of the component in nitrogen- and carbon-containing atmospheres. Such hybrid treatment produces a thicker and harder layer than the other three processes investigated.

  12. Dynamics of cathode spots in low-pressure arc plasma removing oxide layer on steel surfaces

    NASA Astrophysics Data System (ADS)

    Tang, Z. L.; Yang, K.; Liu, H. X.; Zhang, Y. C.; Li, H.; Zhu, X. D.

    2016-03-01

    The dynamics of cathode spots has been investigated in low-pressure arc plasma for removing oxide layer on low carbon steel surfaces. The motion of cathode spots was observed with a high speed camera, and the arc voltage was analyzed by fast Fourier transform. The spots move on clean steel surface as a random walk, and the low-frequency components dominated the voltage waveform. However, the spots on steel surfaces with oxide layer tend to burn on the rim of the eroded area formed in the previous arcing, and the low-frequency components decrease correspondingly. The "color" of the colored random noise for arc voltage varies from the approximate brown noise for clean steel surface to pink noise for thick oxide layer, where the edge effect of boundary is considered to play a significant role.

  13. Welding procedure specification. Supplement 1. Records of procedure qualification tests. Gas tungsten arc and shielded metal arc welding of AISI 41XX steels. [4130 and 4142 steels

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.

    1986-06-01

    Procedure WPS-127 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of AISI 4130 and 4142 steels (ASTM A519) (P-No: None), 0.438-inch wall pipe; filler metal is AMS 6457, Class 4130 MC (F-, A-No: None) (GTAW) and E8018-B2L (F-4, A-3) (GMAW): shielding gas is argon (GTAW).

  14. 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.

  15. 49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Specification 4BW welded steel cylinders with... steel cylinders with electric-arc welded longitudinal seam. (a) Type, size and service pressure. A DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a...

  16. 49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Specification 4BW welded steel cylinders with... steel cylinders with electric-arc welded longitudinal seam. (a) Type, size and service pressure. A DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a...

  17. 49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Specification 4BW welded steel cylinders with... steel cylinders with electric-arc welded longitudinal seam. (a) Type, size and service pressure. A DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a...

  18. 49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Specification 4BW welded steel cylinders with... steel cylinders with electric-arc welded longitudinal seam. (a) Type, size and service pressure. A DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a...

  19. Stainless steel submerged arc weld fusion line toughness

    SciTech Connect

    Rosenfield, A.R.; Held, P.R.; Wilkowski, G.M.

    1995-04-01

    This effort evaluated the fracture toughness of austenitic steel submerged-arc weld (SAW) fusion lines. The incentive was to explain why cracks grow into the fusion line in many pipe tests conducted with cracks initially centered in SAWS. The concern was that the fusion line may have a lower toughness than the SAW. It was found that the fusion line, Ji. was greater than the SAW toughness but much less than the base metal. Of greater importance may be that the crack growth resistance (JD-R) of the fusion line appeared to reach a steady-state value, while the SAW had a continually increasing JD-R curve. This explains why the cracks eventually turn to the fusion line in the pipe experiments. A method of incorporating these results would be to use the weld metal J-R curve up to the fusion-line steady-state J value. These results may be more important to LBB analyses than the ASME flaw evaluation procedures, since there is more crack growth with through-wall cracks in LBB analyses than for surface cracks in pipe flaw evaluations.

  20. Leaching behavior of pollutants in ferrochrome arc furnace dust and its stabilization/solidification using ferrous sulphate and Portland cement.

    PubMed

    Bulut, Ulkü; Ozverdi, Arzu; Erdem, Mehmet

    2009-03-15

    In this study, dissolution properties under different conditions and pollution potential by toxicity characteristic leaching procedure (TCLP) of arc furnace dust generated in the production of ferrochrome were examined and some stabilization/solidification (S/S) techniques were applied to the dust depending on contaminants determined. Dissolution properties and pollution potentials of all the materials stabilized/solidified were also studied under the similar conditions. It was determined that the metallic components concentrations dissolved from the ferrochrome arc furnace dust (FAFD) except for chromium and zinc were below the detection limits. The chromium concentration dissolved from the FAFD by TCLP was found to be 9.8 mg/l. Portland cement (PC), PC-FeSO(4) and PC-sand-FeSO(4) mixtures for S/S of the FAFD were tested. Although metal ions in the cationic form were stabilized when the PC was only used, Cr(VI) in the sample was not changed depending on PC amount and remained in the soluble chromate form. The stabilization efficiency of Cr(VI) increased by the increasing amounts of PC and FeSO(4). The best S/S of the FAFD was accomplished when the 5 stoichiometric amounts of FeSO(4), 30% PC and 16% sand mixture were used. TCLP leaching results of the samples obtained under the optimum conditions were below the EPA landfilling limits.

  1. 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.

  2. Blue-light hazard from CO2 arc welding of mild steel.

    PubMed

    Okuno, T; Ojima, J; Saito, H

    2010-04-01

    The objective was to quantify the blue-light hazard from CO(2) arc welding of mild steel. The spectral radiance of arcs in CO(2) arc welding of mild steel was measured for solid and flux-cored wires at welding currents of 120-480 A. Effective blue-light radiance and the maximum acceptable exposure duration were calculated from the spectral radiance using their definitions in American Conference of Governmental Industrial Hygienists guidelines. The effective blue-light radiance ranged from 22.9 to 213.1 Wcm(-2)sr(-1). The corresponding maximum acceptable exposure duration was only 0.47-4.36 s, meaning that the total daily exposure to the welding arc without eye protection should not exceed this duration. It is very hazardous to view the arcs in CO(2) arc welding of mild steel. Welders and their helpers should use appropriate eye protectors in these arc-welding operations. Also, they should avoid direct light exposure when starting an arc-welding operation.

  3. Process of vacuum hardening of cutting and sharpening tools of high-speed steels in belt furnaces

    NASA Astrophysics Data System (ADS)

    Tarasovi, A. N.

    1996-12-01

    The technical possibilities of vacuum elevator and bell furnaces commonly used for brazing and annealing precision parts in instrument-making and electronics can be widened. Small thin-blade tools of powder steels R6M5-P, 10R6M5-MP and "silver" steels R6M5, R6M5K5 with a minimum tolerance for sizing after hardening at a low cooling rate have high operational properties. The present paper is devoted to the process of heat treatment of special tools of the listed steels used to cut and shape ribbons, rods, and foils of alloys 36NKhTYu, 29NK, BrB2 in vacuum bcil furnaces under conditions of batch and small-batch production in electrical-engineering enterprises.

  4. 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.

  5. Strength and structure of furnace-brazed joints between aluminum and stainless steel

    SciTech Connect

    Roulin, M.; Karadeniz, G.; Mortensen, A.; Luster, J.W.

    1999-05-01

    The structure and shear strength of brazed joints of aluminum to stainless steel are studied using a modification of the double lap joint configuration, which allows mechanical testing and joint microstructure examination on the same test piece. It is found that during furnace brazing of such joints at 600 C, using an Al-Si eutectic brazing alloy, the interfacial zone between the aluminum-rich braze and the stainless steel substrate features two intermetallic layers. The first is formed in the initial instants of the process and features an overall composition similar to that of the compound FeSiAl{sub 5}. The second appears after a 10-min hold time at the brazing temperature, and features an overall composition that parallels the FeAl{sub 3} intermetallic. Both layers are, however, more complex in structure than is suggested by these stoichiometric relations. The shear strength of the braze peaks at 21 MPa after a 10-min hold time at the brazing temperature. This peak is associated with nucleation of the second intermetallic layer, which is shown to fragilize the joint significantly. The presence of silicon in the brazing alloy would also seem to be beneficial by retarding formation of this second, more fragile Fe-Al intermetallic layer; however, more work is needed to substantiate this tentative conclusion.

  6. 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.

  7. 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.

  8. 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.

    2016-11-01

    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.

  9. 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.

  10. Thermocapillary and arc phenomena in stainless steel welding

    SciTech Connect

    Pierce, S.W.; Olson, D.L.; Burgardt, P.

    1999-02-01

    This investigation characterized the effects of power level and Gaussian heat source size on thermocapillary-induced weld shape and estimated the relative influence of various possible arc phenomena in determining weld shape. Welds made with the CTAW process were compared with similar ones made with a conduction-mode EBW process and the differences were related to arc effects. Evidence of thermocapillary flow was readily apparent in both the GTA welds and the conduction-mode EB welds and was qualitatively similar in both. The similarity between the results obtained with the two processes serves to demonstrate that thermocapillary convection is the dominant factor in heat-to-heat weld shape variability. However, a similar one-to-one correspondence between welds produced with the two processes does not exist. Especially at high power, the EB welds showed stronger thermocapillary convection than the GTA welds. One important arc factor that limits thermocapillary flow in ar welds appears to be an increase in arc size with arc length and arc current. A non-Gaussian arc power distribution in GTAW seems to be most important in limiting the fluid flow. Apparently, the arc power distribution is more nearly rectangular in shape for an argon gas arc. At higher currents, above 200 A, plasma shear force may also be an important contributor to weld shape development. The conduction-mode EB welds demonstrate that thermocapillary flow reversal probably does not occur in welds made with a simple Gaussian heat source. The complex shape behavior is likely a result of an arc effect such as plasma shear.

  11. Investigation of stabilization/solidification for treatment of electric arc furnace dust: Dynamic leaching of monolithic specimens

    SciTech Connect

    Laforest, Guylaine Duchesne, Josee

    2007-12-15

    Diffusion-controlled leaching of heavy metals (Cr, Ni, Pb and Zn) from electric arc furnace dust treated with ground granulated blast furnace slag (GGBFS) and with ordinary Portland cement (OPC) was evaluated. Monolithic specimens were evaluated under dynamic leaching conditions for 84 days with periodic leachant renewal. The influence of leaching time, nature of the leachant, binder type and the water/solid ratio of the monoliths were investigated. Results obtained showed both binders can immobilize heavy metals in the monoliths under dynamic leaching conditions, with cumulative quantity of leached metal under 0.138 mg (Cr). Alkaline leachant increased metal release from specimens and reducing the water/solid ratio of the monolith allowed for a decrease in the cumulative mass of metals leached. Chemical and mineralogical characterizations indicated that the metals were evenly distributed throughout the specimens for both binders. Decalcification was observed on the OPC monolith border following leaching. This decrease in Ca corresponded to an altered zone (20 {mu}m), identified by scanning electron microscopy. The GGBFS sample did not show an altered zone.

  12. EXTERIOR VIEW, BLAST FURNACE NO. 3 (JANE FURNACE) CENTER, NO. ...

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

    EXTERIOR VIEW, BLAST FURNACE NO. 3 (JANE FURNACE) CENTER, NO. 3 CAST HOUSE TO THE LEFT, WEST ORE BRIDGE TO THE RIGHT. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

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

    DOEpatents

    Howard, Stanley R.; Korinko, Paul S.

    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.

  14. An approach for phosphate removal with quartz sand, ceramsite, blast furnace slag and steel slag as seed crystal.

    PubMed

    Qiu, Liping; Wang, Guangwei; Zhang, Shoubin; Yang, Zhongxi; Li, Yanbo

    2012-01-01

    The phosphate removal abilities and crystallization performance of quartz sand, ceramsite, blast furnace slag and steel slag were investigated. The residual phosphate concentrations in the reaction solutions were not changed by addition of the ceramsite, quartz sand and blast furnace slag. The steel slag could provide alkalinity and Ca(2+) to the reaction solution due to its hydration activity, and performed a better phosphate removal performance than the other three. Under the conditions of Ca/P 2.0, pH 8.5 and 10 mg P/L, the phosphate crystallization occurred during 12 h. The quartz sand and ceramsite did not improve the phosphate crystallization, but steel slag was an effective seed crystal. The phosphate concentration decreased drastically after 12 h after addition of steel slag, and near complete removal was achieved after 48 h. The XRD analysis showed that the main crystallization products were hydroxyapatite (HAP) and the crystallinity increased with the reaction time. Phosphate was successfully recovered from low phosphate concentration wastewater using steel slag as seed material.

  15. Computational Modeling of Microstructural-Evolution in AISI 1005 Steel During Gas Metal Arc Butt Welding

    DTIC Science & Technology

    2013-05-01

    applied to a prototypical (plain) low- carbon steel (AISI 1005) to predict the distribution of various crystalline phases within the as-welded material...a prototypical (plain) low- carbon steel (AISI 1005) to predict the distribution of various crystalline phases within the as-welded material micro...arc voltage/current should be placed between the short- circuiting and spray transfer/mode counterparts. Typically, using carbon dioxide as a

  16. 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.

  17. Welding procedure specification: gas tungsten arc and shielded metal arc welding of carbon steel. Supplement 1. Records of procedure qualification tests

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1986-06-01

    Procedure WPS-2103-ASME-1 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of carbon steels (P-1-1) to 300 series Cr-Ni steels (P-8-1), in thickness range 0.25 to 2.0 inch; filler metals are ERNiCr-3 (F-43 (GTAW) and ENiCrFe-3 (F-43) (SMAW); shielding gas is argon (GTAW).

  18. Regularities of heat transfer in the gas layers of a steam boiler furnace flame. Part II. Gas layer radiation laws and the procedure for calculating heat transfer in furnaces, fire boxes, and combustion chambers developed on the basis of these laws

    NASA Astrophysics Data System (ADS)

    Makarov, A. N.

    2014-10-01

    The article presents the results stemming from the scientific discovery of laws relating to radiation from the gas layers generated during flame combustion of fuel and when electric arc burns in electric-arc steel-melting furnaces. The procedure for calculating heat transfer in electric-arc and torch furnaces, fire-boxes, and combustion chambers elaborated on the basis of this discovery is described.

  19. Furnace brazing type 304 stainless steel to vanadium alloy (V?5Cr?5Ti)

    NASA Astrophysics Data System (ADS)

    Steward, R. V.; Grossbeck, M. L.; Chin, B. A.; Aglan, H. A.; Gan, Y.

    2000-12-01

    In this investigation, pure copper was joined to type 304 stainless steel and V-5Cr-5Ti by brazing in a high vacuum furnace. Microstructural changes in the brazed region and surrounding substrates were examined as a function of holding time at temperatures of 20°C, 40°C and 60°C above the melting point of copper. Reaction layers, which were extremely brittle, formed between the Cu and V-5Cr-5Ti substrates. The formation of intermetallic phases at the filler metal/substrate interfaces was evaluated. Additionally, precipitates (FeCu 2 and FeCu 18) formed in the Cu rich filler region. For temperatures ⩾60°C above the melting point of Cu, extensive transverse cracking was observed. Hardness tests substantiated the hypothesis that the Cu/V-5Cr-5Ti reaction layer was extremely brittle, since micro-cracks propagated from the tips of the diamond-shaped indentations. Results of mechanical properties tests of the brazed material are also presented.

  20. Correlation of Flux Composition and Inclusion Characteristics With Submerged Arc Weld Metal Properties in HY-100 Steel

    DTIC Science & Technology

    1993-09-01

    WITH SUBMERGED ARC WELD METAL PROPERTIES IN HY- 100 STEEL by Kent William Kettell September 1993 Thesis Advisor: Alan G. Fox Approved for public... STEEL 12. PERSONAL AUTHOR(S) Kettell, Kent William ,3a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year.Month.Day) 15. PAGE COUNT Master’s...necessary and identify by block number) FIELD GROUP SUB-GROUP HY- 100 steel , submerged arc welding, SAW, fluxes, basicity index, non-metallic inclusions

  1. Differences between Laser and Arc Welding of HSS Steels

    NASA Astrophysics Data System (ADS)

    Němeček, Stanislav; Mužík, Tomáš; Míšek, Michal

    Conventional welding processes often fail to provide adequate joints in high strength steels with multiphase microstructures. One of the promising techniques is laser beam welding: working without filler metal and with sufficient capacity for automotive and transportation industry (where the amount of AHSS steels increases each year, as well as the length of laser welds). The paper compares microstructures and properties of HSS (high strength steel) joints made by MAG (Metal Active Gas) and laser welding. The effects of main welding parameters (heat input, welding speed and others) are studied on multiphase TRIP 900 steel tubes and martensitic sheets DOCOL 1200, advanced materials for seat frames and other automotive components. Whereas the strength of conventional welds is significantly impaired, laser welding leaves strength of the base material nearly unaffected. As the nature of fracture changes during loading and depending on the welding method, failure mechanisms upon cross tension tests have been studied as well.

  2. Thermocapillary and arc phenomena in stainless steel welds

    SciTech Connect

    Pierce, S.W.

    1993-10-01

    Goal was to study effect of power level and distribution on thermocapiilary-induced weld shape and of arc factors on weld shape. Thermocapillarity was apparent in both conduction mode EB welds and GTA welds, particularly in the former. A non-Gaussian arc distribution is suggested for accounting for the differences between the twoss processes. At higher current levels (200--300 A), plasma shear force also contributes to weld shape development. Evidence suggests that thermocapillary flow reversal is not a factor in normal GTA welds; EDB flow reversal occurs only at high power density levels where the keyhole mode is present.

  3. Plasma arc welding Hp-9Ni-4Co-0.30C steel

    SciTech Connect

    Harwig, D.D.; Hunt, J.F.; Theus, G.J.

    1994-12-31

    The plasma arc welding process is used to fabricate the advanced solid rocket motor (ASRM) casing for the Space Shuttle. Plasma arc welding (PAW) was chosen because this process assures a full penetration root pass with the keyhole mode. The HP 9Ni-4Co-0.30C steel was chosen for the ASRM application because the material has excellent strength, toughness, and weldability. The minimum mechanical property requirements of the weldment are 190 ksi yield, 205 ksi ultimate, 8% elongation, 25% reduction in area and 90 ksi/in. fracture toughness. Therefore, a comprehensive development plan was performed to fully characterize plasma arc welding HP 9Ni-4Co-0.30 steel. The test technique systematically varied the essential plasma arc parameters: current, travel speed, plasma gas or wire feed speed while maintaining constant arc length and torch set-up conditions. This PWHT produced the best combination of strength, toughness, and acceptable residual stresses. Variations in land thickness, plasma gas flow rate, current, travel speed, and arc length were characterized by measuring weld bead shape geometry. The weld procedure was found to be tolerant to rather wide parameter variations.

  4. Structure-property correlation of submerged-arc and gas-metal-arc weldments in HY-100 steel

    NASA Astrophysics Data System (ADS)

    Deb, P.; Challenger, K. D.; Therrien, A. E.

    1991-01-01

    Structure-property relationships of two HY-100 steel weldments prepared by submerged arc (SAW) and gas metal arc (GMAW) welding processes using identical heat input (2.2 kJ mm-1) have been studied. It has been found that submerged arc welded (SAW) HY-100 steel weldments have a lower weld toughness than welds produced by the gas metal arc welding (GMAW) process. Optical, scanning, and transmission electron microscopy were used in conjunction with microhardness traverses to characterize and compare the various microconstituents that are present in the last weld pass of both weldments. TEM examination revealed the presence of coarse upper bainite, B-II bainite, and carbides in a highly dislocated ferrite matrix as well as in ferrite laths in the SAW weldment, while the GMAW weldment exhibited a typical fine low carbon lath martensite, autotempered martensite, and mixed B-II and B-III bainites which occasionally contained small regions of twinned martensite. The measured cooling rate in the SAW was found to be about 40 pct slower than that in GMAW. It was also found in the SAW that the weld metal inclusion number density was about 25 pct greater than that in GMAW. Micro-hardness traverses exhibited significantly lower hardness (about 50 HV) in the SAW weldment compared with GMAW, but the tempered weld metal microhardness in both the weldments was measured about the same, at 250 HV. The ductile-to-brittle transition temperature (DBTT) of both weldments was determined by Charpy impact test. Based on an average energy criterion, the DBTT of the SAW weldment was 323 K (50 °C) higher than that of the GMAW weldment. This difference in fracture resistance is due to the different weld metal microstructures. The different microstructures most probably result from differences in cooling rate subsequent to welding; however, the SAW weld also has a higher inclusion number density which could promote a higher transformation temperature for the austenite.

  5. Structure-property correlation of submerged-arc and gas-metal-arc weldments in HY-100 steel

    NASA Astrophysics Data System (ADS)

    Deb, P.; Challenger, K. D.; Therrien, A. E.

    1987-01-01

    Structure-property relationships of two HY-100 steel weldments prepared by submerged arc (SAW) and gas metal arc (GMAW) welding processes using identical heat input (2.2 kJ mm-1) have been studied. It has been found that submerged arc welded (SAW) HY-100 steel weldments have a lower weld toughness than welds produced by the gas metal arc welding (GMAW) process. Optical, scanning, and transmission electron microscopy were used in conjunction with microhardness traverses to characterize and compare the various microconstituents that are present in the last weld pass of both weldments. TEM examination revealed the presence of coarse upper bainite, B-II bainite, and carbides in a highly dislocated ferrite matrix as well as in ferrite laths in the SAW weldment, while the GMAW weldment exhibited a typical fine low carbon lath martensite, autotempered martensite, and mixed B-II and B-III bainites which occasionally contained small regions of twinned martensite. The measured cooling rate in the SAW was found to be about 40 pct slower than that in GMAW. It was also found in the SAW that the weld metal inclusion number density was about 25 pct greater than that in GMAW. Micro-hardness traverses exhibited significantly lower hardness (about 50 HV) in the SAW weldment compared with GMAW, but the tempered weld metal microhardness in both the weldments was measured about the same, at 250 HV. The ductile-to-brittle transition temperature (DBTT) of both weldments was determined by Charpy impact test. Based on an average energy criterion, the DBTT of the SAW weldment was 323 K (50 °C) higher than that of the GMAW weldment. This difference in fracture resistance is due to the different weld metal microstructures. The different microstructures most probably result from differences in cooling rate subsequent to welding; however, the SAW weld also has a higher inclusion number density which could promote a higher transformation temperature for the austenite.

  6. Structure-property correlation of submerged-arc and gas-metal-arc weldments in HY-100 steel

    NASA Astrophysics Data System (ADS)

    Deb, P.; Challenger, K. D.; Therrien, A. E.

    1987-06-01

    Structure-property relationships of two HY-100 steel weldments prepared by submerged arc (SAW) and gas metal arc (GMAW) welding processes using identical heat input (2.2 kJ mm-1) have been studied. It has been found that submerged arc welded (SAW) HY-100 steel weldments have a lower weld toughness than welds produced by the gas metal arc welding (GMAW) process. Optical, scanning, and transmission electron microscopy were used in conjunction with microhardness traverses to characterize and compare the various microconstituents that are present in the last weld pass of both weldments. TEM examination revealed the presence of coarse upper bainite, B-II bainite, and carbides in a highly dislocated ferrite matrix as well as in ferrite laths in the SAW weldment, while the GMAW weldment exhibited a typical fine low carbon lath martensite, autotempered martensite, and mixed B-II and B-III bainites which occasionally contained small regions of twinned martensite. The measured cooling rate in the SAW was found to be about 40 pct slower than that in GMAW. It was also found in the SAW that the weld metal inclusion number density was about 25 pct greater than that in GMAW. Micro-hardness traverses exhibited significantly lower hardness (about 50 HV) in the SAW weldment compared with GMAW, but the tempered weld metal microhardness in both the weldments was measured about the same, at 250 HV. The ductile-to-brittle transition temperature (DBTT) of both weldments was determined by Charpy impact test. Based on an average energy criterion, the DBTT of the SAW weldment was 323 K (50 °C) higher than that of the GMAW weldment. This difference in fracture resistance is due to the different weld metal microstructures. The different microstructures most probably result from differences in cooling rate subsequent to welding; however, the SAW weld also has a higher inclusion number density which could promote a higher transformation temperature for the austenite.

  7. Emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans from stack gases of electric arc furnaces and secondary aluminum smelters.

    PubMed

    Lee, Wei-Shan; Chang-Chien, Guo-Ping; Wang, Lin-Chi; Lee, Wen-Jhy; Wu, Kuen-Yuh; Tsai, Perng-Jy

    2005-02-01

    This study investigates the emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) from four electric arc furnaces (EAFs) and eight secondary aluminum smelters (secondary ALSs) in Taiwan. The mean PCDD/F International-Toxicity Equivalents (I-TEQ) concentrations in the stack gases of these EAFs and secondary ALSs are 0.28 ng I-TEQ/Nm3 (relative standard deviation [RSD]= 100%) and 3.3 ng I-TEQ/Nm3 (RSD = 260%), respectively. The high RSDs, especially for those obtained from secondary ALSs, could be caused by the intrinsic differences in their involved feeding materials, furnace operating conditions, and air pollution control devices. The mean I-TEQ emission factor of PCDD/Fs for EAFs (1.8 microg I-TEQ/tonne-feedstock) is lower than that for secondary ALSs (37 microg I-TEQ/tonne-feedstock). This result might be because the involved furnace temperatures for secondary ALSs (650-750 degrees C) are lower than those for EAFs (1600-1700 degrees C), resulting in the deterioration of the combustion condition, leading to the formation of PCDD/Fs during the industrial process. This study found that the total PCDD/F emissions from EAFs (20 g I-TEQ/yr) and secondary ALSs (18 g I-TEQ/yr) are approximately 27, 53, and approximately 24, 49 times higher than those from municipal solid waste incinerators (MSWIs; 0.74 g I-TEQ/yr) and medical waste incinerators (MWIs; 0.37 g I-TEQ/yr), respectively; while those are 44 and 40% of total PCDD/F emission from sinter plants (45 g I-TEQ/ yr), respectively. Considering a more stringent emission limit has been applied to waste incinerators (0.1 ng I-TEQ/Nm3) in Taiwan lately, the results suggest that the control of the emissions from metallurgical processes has become the most important issue for reducing the total PCDD/F emission from industrial sectors to the ambient environment.

  8. Destruction of inorganic municipal solid waste incinerator fly ash in a DC arc plasma furnace.

    PubMed

    Zhao, Peng; Ni, Guohua; Jiang, Yiman; Chen, Longwei; Chen, Mingzhou; Meng, Yuedong

    2010-09-15

    Due to the toxicity of dioxins, furans and heavy metals, there is a growing environmental concern on municipal solid waste incinerator (MSWI) fly ash in China. The purpose of this study is directed towards the volume-reduction of fly ash without any additive by thermal plasma and recycling of vitrified slag. This process uses extremely high-temperature in an oxygen-starved environment to completely decompose complex waste into very simple molecules. For developing the proper plasma processes to treat MSWI fly ash, a new crucible-type plasma furnace was built. The melting process metamorphosed fly ash to granulated slag that was less than 1/3 of the volume of the fly ash, and about 64% of the weight of the fly ash. The safety of the vitrified slag was tested. The properties of the slag were affected by the differences in the cooling methods. Water-cooled and composite-cooled slag showed more excellent resistance against the leaching of heavy metals and can be utilized as building material without toxicity problems. Copyright 2010 Elsevier B.V. All rights reserved.

  9. 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.

  10. Gas Metal Arc Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade Martensitic Steel

    DTIC Science & Technology

    2013-06-01

    most of the commercially available metallic materials, in particular steels (including stainless steels ), super alloys, aluminum alloys, etc., can...REPORT Gas Metal Arc Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade Martensitic Steel 14. ABSTRACT 16...Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade Martensitic Steel Report Title ABSTRACT A conventional gas metal

  11. 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.

  12. Aluminum Bronze Alloys to Improve the System Life of Basic Oxygen and Electric Arc Furnace Hoods, Roofs and Side Vents.

    SciTech Connect

    Lawrence C. Boyd Jr.; Dr. Vinod K. Sikka

    2006-12-29

    Energy Industries of Ohio was the lead organization for a consortium that examined the current situation involving the service life of electric arc and basic oxygen furnace hoods, roofs and side vents. Republic Engineered Products (REP), one of the project partners, installed a full-scale Al-Bronze “skirt” in their BOF at their Lorain OH facility, believed to be the first such installation of this alloy in this service. In 24 months of operation, the Al-Bronze skirt has processed a total of 4,563 heats, requiring only 2 shutdowns for maintenance, both related to physical damage to the skirt from operational mishaps. Yearly energy savings related to the REP facility are projected to be ~ 10 billion Btu's with significant additional environmental and productivity benefits. In recognition of the excellent results, this project was selected as the winner of the Ohio’s 2006 Governor’s Award for Excellence in Energy, the state’s award for outstanding achievements in energy efficiency.

  13. Inertization of pyrite cinders and co-inertization with electric arc furnace flue dusts by pyroconsolidation at solid state.

    PubMed

    Viñals, J; Balart, M J; Roca, A

    2002-01-01

    The viability of a pyroconsolidation process to render pyrite cinders inert and to co-inert pyrite cinders with a hazardous polymetallic residue such as electric arc furnace flue dusts (EAF) containing Pb, Cu, Zn, As, Cr, Ni and Mo were investigated. The effects of pyroconsolidation temperature (800-1200 degrees C), milling pyrite cinders and additions of both CaO and EAF on the resulting microstructure of the pellets were determined. The microstructural changes were then compared with the results of the standard leaching tests. Full inertization of pyrite cinders was achieved after milling to < 100 micron followed by a pelletization and pyroconsolidation process at a temperature of 1200 degrees C. This process also allows co-inertization of pyrite cinders with controlled additions of EAF (up to approximately to 10%). Following pyroconsolidation at 1200 degrees C, the metallic elements were inert components in the four main phases: traces of Cr in hematite; Cr, Cu, Zn and Ni in spinel-phase; traces of Cr and Zn in calcium ferrites; and Pb and traces of Cu, Zn and Ba in K-Ca-Al-Fe glassy silicate.

  14. Citotoxicity status of electroplating wastewater prior/after neutralization/purification with alkaline solid residue of electric arc furnace dust.

    PubMed

    Orescanin, Visnja; Kopjar, Nevenka; Durgo, Ksenija; Elez, Loris; Gustek, Stefica Findri; Colic, Jasna Franekic

    2009-02-15

    Toxicological safety of new procedure for the neutralisation/purification of wastewater originated from zinc plating facility was investigated. Wastewater was treated with alkaline solid residue-by-product of zinc recovery from electric arc furnace dust. For determination of cytotoxic potential of untreated and purified wastewater MTT test on HEp2 (human laryngeal carcinoma) and HeLa (human cervical carcinoma) cells lines and alkaline comet assay on human leukocytes were used. Then 100% of the sample as well as different dilutions were tested. Compared to negative control 100, 75 and 50% of the sample of untreated wastewater significantly decreased survival of both HEp2 and HeLa cell lines. In the presence of undiluted sample survival percentage of HeLa and HEp2 cells were only 2.3 and 0.3% respectively. Only undiluted purified wastewater showed slight but insignificant decrease of the survival of both cell lines. Even 0.5% of the sample of original electroplating wastewater exhibited significantly higher value of all comet assay parameters compared to negative control. There was no significant difference between negative control and purified wastewater for any of comet assay parameters. Significantly lower level of primary DNA damage recorded after treatment with purified water, even comparable with negative control, confirmed effectiveness of the purification process.

  15. Distribution of air and serum PCDD/F levels of electric arc furnaces and secondary aluminum and copper smelters.

    PubMed

    Lee, Ching-Chang; Shih, Tung-Seng; Chen, Hsiu-Ling

    2009-12-30

    Metallurgical processes, such as smelting, can generate organic impurities such as organic chloride chemicals, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs). The objective of this study was to elucidate the serum PCDD/F levels of 134 workers and ambient air levels around electric arc furnaces (EAF), secondary copper smelters and secondary aluminum smelters (ALSs) in Taiwan. The highest serum PCDD/F levels were found in the ALSs workers (21.9 pg WHO-TEQ/g lipid), with lower levels in copper smelter workers (21.5 pg WHO-TEQ/g lipid), and the lowest in the EAF plant workers (18.8 pg WHO-TEQ/g lipid). This was still higher than the levels for residents living within 5 km of municipal waste incinerators (14.0 pg WHO-TEQ/g lipid). For ambient samples, the highest ambient air PCDD/F level was in the copper smelters (12.4 pg WHO-TEQ/Nm(3)), with lower levels in ALSs (7.2 pg WHO-TEQ/Nm(3)), and the lowest in the EAF industry (1.8 pg WHO-TEQ/Nm(3)). The congener profiles were consistent in serum and in air samples collected in the copper smelters, but not for ALSs and EAF. In secondary copper smelters, the air PCDD/Fs levels might be directly linked to the PCDD/Fs accumulated in the workers due to the exceedingly stable congener pattern of the PCDD/F emission.

  16. Removal of vapour phase PCDD/Fs in electric arc furnace steelmaking emissions by sorption using plastics.

    PubMed

    Ooi, Tze Chean; Ewan, Bruce C R; Cliffe, Keith R; Anderson, David R; Fisher, Raymond; Thompson, Dennis

    2008-08-01

    Plastics are potentially suitable for the removal of vapour phase PCDD/Fs in emissions from the electric arc furnace (EAF) steelmaking process. Three different commercial plastics, i.e. polypropylene BE170MO (Borealis A/S, Denmark), polypropylene in the form of 5 mm spheres (The Precision Plastic Ball Co. Ltd., UK) and polyethylene LD605BA (ExxonMobil Chemical, Belgium), have been studied using a novel experimental apparatus for the removal of vapour phase PCDD/Fs. Polypropylene BE170MO was identified to be the most suitable product amongst the three plastics in terms of PCDD/F sorption and potential industrial application. The optimum temperature for PCDD/F sorption on polypropylene BE170MO was below 90 degrees C for a removal efficiency of >99% at an average vapour phase PCDD/F concentration of 3.5 ng I-TEQ/Nm(3). At 130 degrees C, 53% of the PCDD/Fs trapped on polypropylene BE170MO were desorbed.

  17. Hydrometallurgical process for zinc recovery from electric arc furnace dust (EAFD). Part II: Downstream processing and zinc recovery by electrowinning.

    PubMed

    Tsakiridis, P E; Oustadakis, P; Katsiapi, A; Agatzini-Leonardou, S

    2010-07-15

    The characterization and the agitation leaching of electric arc furnace dust (EAFD) by diluted sulphuric acid have been studied in Part I, as a separate article. The aim of the present research work (Part II) is the development of a purification process of the leach liquor for the recovery of high-purity zinc by electrowinning. The proposed hydrometallurgical process consists of the following four (4) unit operations: (1) Removal of iron as easily filterable crystalline basic sulphate salt of the jarosite type, at atmospheric pressure, by chemical precipitation at pH: 3.5 and 95 degrees C. (2) Zinc solvent extraction by Cyanex 272 at pH: 3.5, T: 40 degrees C, with 25% extractant concentration. (3) Stripping of the loaded organic phase by zinc spent electrolyte (62.5 g/L Zn(2+)) at T: 40 degrees C with diluted H(2)SO(4) (3 mol/L). (4) Zinc electrowinning from sulphate solutions (at 38 degrees C) using Al as cathode and Pb as anode. The acidity of the electrolyte was fixed at 180 g/L H(2)SO(4), while the current density was kept constant at 500 A/m(2).

  18. 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.

  19. A novel hydrothermal method for zinc extraction and separation from zinc ferrite and electric arc furnace dust

    NASA Astrophysics Data System (ADS)

    Wang, Hui-gang; Li, Yang; Gao, Jian-ming; Zhang, Mei; Guo, Min

    2016-02-01

    A novel hydrothermal process was developed to extract zinc from pure zinc ferrite (ZnFe2O4) nanopowder and zinc-containing electric arc furnace (EAF) dust using hexahydrated ferric chloride (FeCl3·6H2O) as a decomposing agent. The effects of solid FeCl3·6H2O to ZnFe2O4 ratio by mass ( R F/Z), hydrothermal reaction temperature, and time on zinc extraction were systematically investigated. In the results, when the hydrothermal reaction is conducted at 150°C for 2 h with R F/Z of 15:20, the efficiency of zinc extraction from ZnFe2O4 reaches 97.2%, and the concentration of ferric ions (Fe3+) in the leaching solution is nearly zero, indicating a high selectivity for zinc. In addition, the zinc extraction efficiency from the EAF dust reaches 94.5% in the case of the hydrothermal reaction performed at 200°C for 10 h with the solid FeCl3·6H2O to EAF dust ratio by mass ( R F/EAF dust) of 15:10. Zinc and iron separation is achieved by adjusting the pH value of the leaching solution according to the different precipitation pH values of metal hydroxides.

  20. 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.

  1. Evaluation of ASD systems for electric arc furnace and argon oxygen decarburization refiner baghouse fans. Final report

    SciTech Connect

    1997-11-01

    Adjustable speed drive (ASD) control of the baghouse fans for Electric Arc Furnace (EAF) and Argon Oxygen Decarburization Vessel (AOD) can improve operations, reduce the degree of dust generation, and provide significant energy savings. The purpose of the project was to quantify the benefits, both in energy savings and other process improvements and to demonstrate the methodology of applying adjustable speed drives, to two baghouse fans from a system perspective. The report describes the approach to accomplishing the ASD equipment installation, the test procedure and methodology and provides the test results and economic return. The test results indicated that by using ASDs to control the extraction fan air flow for the EAF and AOD, the following benefits would be achieved on an annual basis: EAF annual energy savings, 267,929 kWh valued at $11,575; EAF dust reduction, overall, 2--3%; EAF dust reduction, during the flatbath period, 35%; and AOD annual energy savings, 1,443,078 kWh valued at $62,341.

  2. Slag Metal Reactions during Submerged Arc Welding of Alloy Steels

    NASA Astrophysics Data System (ADS)

    Mitra, U.; Eagar, T. W.

    1984-01-01

    The transfer of Cr, Si, Mn, P, S, C, Ni, and Mo between the slag and the weld pool has been studied for submerged arc welds made with calcium silicate and manganese silicate fluxes. The results show a strong interaction between Cr and Si transfer but no interaction with Mn. The manganese silicate flux produces lower residual sulfur while the calcium silicate fluxes are more effective for removal of phosphorus. The effective oxygen reaction temperature lies between 1700 and 2000 °C for all elements studied. Evidence of Cr and Mn loss by metal vaporization is also presented.

  3. Shielded Metal Arc Welding Consumables for Advanced High Strength Steels

    DTIC Science & Technology

    1992-02-01

    100 ksi) depends on the availability of adequate welding consumables. In the case of shielded metal arc welding, the electrodes must provide...associated with the potassium silicate binder (K2 SiO3 .nH2 0). The fluxes were then crushed and sized to 14# Tyler mesh (1.7 mm screen aperture) to...determined that the hydrated potassium silicate binder (K2 SiO3 .nH20) used in this investi- gation was 50 wt. pct. potassium silicate (K 2SiO 3 ) and

  4. Effect of PTA Hardfaced Interlayer Thickness on Ballistic Performance of Shielded Metal Arc Welded Armor Steel Welds

    NASA Astrophysics Data System (ADS)

    Balakrishnan, M.; Balasubramanian, V.; Madhusudhan Reddy, G.

    2013-03-01

    Ballistic performance of armor steel welds is very poor due to the usage of low strength and low hardness austenitic stainless steel fillers, which are traditionally used to avoid hydrogen induced cracking. In the present investigation, an attempt has been made to study the effect of plasma transferred arc hardfaced interlayer thickness on ballistic performance of shielded metal arc welded armor steel weldments. The usefulness of austenitic stainless steel buttering layer on the armor grade quenched and tempered steel base metal was also considered in this study. Joints were fabricated using three different thickness (4, 5.5, and 7 mm) hardfaced middle layer by plasma transferred arc hardfacing process between the top and bottom layers of austenitic stainless steel using shielded metal arc welding process. Sandwiched joint, in addition with the buttering layer served the dual purpose of weld integrity and ballistic immunity due to the high hardness of hardfacing alloy and the energy absorbing capacity of soft backing weld deposits. This paper will provide some insight into the usefulness of austenitic stainless steel buttering layer on the weld integrity and plasma transferred arc hardfacing layer on ballistic performance enhancement of armor steel welds.

  5. AISI/DOE Technology Roadmap Program: Development of an O2-Enriched Furnace System for Reduced CO2 and NOx Emissions For the Steel Industry

    SciTech Connect

    Edward W. Grandmaison; David J. Poirier; Eric Boyd

    2003-01-20

    An oxygen-enriched furnace system for reduced CO2 and NOx emission has been developed. The furnace geometry, with a sidewall-mounted burner, was similar to configurations commonly encountered in a steel reheat furnace. The effect of stack oxygen concentration, oxygen enrichment level and air infiltration on fuel savings/CO2 reduction, NOx emissions and scale formation were investigated. The firing rate required to maintain the furnace temperature at 1100 C decreased linearly with increasing oxygen enrichment. At full oxygen enrichment a reduction of 40-45% in the firing rate was required to maintain furnace temperature. NOx emissions were relatively constant at oxygen enrichment levels below 60% and decreased concentration at all oxygen enrichment levels. Air infiltration also had an effect on NOx levels leading to emissions similar to those observed with no air infiltration but with similar stack oxygen concentrations. At high oxygen enrichment levels, there was a larger variation in the refractory surface-temperature on the roof and blind sidewall of the furnace. Scale habit, intactness, adhesion and oxidation rates were examined for five grades of steel over a range of stack oxygen concentrations and oxygen enrichment levels at 1100 degree C. The steel grade had the largest effect on scaling properties examined in this work. The stack oxygen concentration and the oxygen enrichment level had much smaller effects on the scaling properties.

  6. Properties of submerged arc welded TMCP-steel weldments

    SciTech Connect

    Kotamies, J.M.N.; Brederholm, A.T.; Haenninen, H.E.

    1996-12-01

    In this investigation weldability, mechanical properties and effects of different heat inputs and welding consumables on the properties of weldments of the thermomechanically control processed (TMCP) steel, RAEX 500M were examined. The hardness measurements and transverse tensile tests showed that HAZ softening was insignificant in the TMCP-steel weldments studied. The weld metal strength properties were equal to or higher than those of the base metal through the heat input range of 2.0 to 6.0 kJ/mm. The required low temperature impact toughness of 40 J was achieved with plate thickness of 40 mm at {minus}60 C with all the filler materials used except with S2Ni2 (welding energy 5.8 kJ/mm) and S2Ni2 with metal powder addition (welding energy 5.9 kJ/mm). With high welding energies and longer cooling times (t{sub 8/5}) favorable weld metal microstructures were achieved with Mo-, Ti- and B-alloyed filler materials.

  7. Application of Hybrid Laser arc Welding for the Joining of Large Offshore Steel Foundations

    NASA Astrophysics Data System (ADS)

    Kristiansen, Morten; Farrokhi, Farhang; Kristiansen, Ewa; Villumsen, Sigurd

    To reduce the costs of the fabrication of offshore wind turbine foundations it is necessary to investigate new fabrication technologies. Hybrid laser arc welding is a potentially well-suited process for this because it requires less groove preparation to achieve deep weld penetration and lower heat input, compared to traditional arc welding. A skirt section of a suction bucket in 16 mm steel was used as a case to investigate the hybrid laser-arc welding in order to demonstrate which types of weld and which weld positions are possible. Three types of weld joints were chosen and welded with different welding positions; a butt joint of a bended section, a butt joint of a flat section and a lap joint. Stable welds with sufficient penetration were achieved for the flat welding position of the butt joint of bended section and butt joint of flat section.

  8. 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.

  9. Electric arc surfacing on low carbon steel: Structure and properties

    NASA Astrophysics Data System (ADS)

    Ivanov, Yurii; Gromov, Victor; Kormyshev, Vasilii; Konovalov, Sergey; Kapralov, Evgenii; Semin, Alexander

    2016-11-01

    By the methods of modern materials science, the structure-phase state and microhardness distribution along the cross-section of single and double coatings surfaced on martensite low carbon steel by alloy powder-cored wire were studied. It was established that the increased mechanical properties of surfaced layer are determined by the sub-micro and nanodispersed martensite structure formation, containing iron borides forming the eutectic of lamellar form. The plates of Fe2B are formed mainly in the eutectic of a single-surfaced layer, while FeB is formed in a double-surfaced layer. The existence of bend extinction contours indicating the internal stress fields formation at the boundaries of Fe borides-α-Fe phases were revealed.

  10. Welding procedure specification. Supplement 1. Records of procedure qualification tests. Gas tungsten arc and low hydrogen shielded metal arc welding of carbon steel

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1986-06-01

    Procedure WPS-128-ASME-1 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and low hydrogen shielded metal arc welding of carbon steels (P-1-1), in thickness range 0.25 to 2.0 inch; filler metals are ER70S-3) (F-6, A-1) (GTAW) and E7018 (F-4, A-1); shielding gas is argon (GTAW).

  11. Welding procedure specification. Supplement 1. Records of procedure qualification tests. Gas tungsten arc and shielded metal arc welding of chromium-nickel steel. [300 series

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1986-06-01

    Procedure WPS-303-ASME-3 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of 300 Series Cr-Ni steels (P-8-1), in thickness range 0.25 to 2.0 inch; filler metals are ER3XX (F-6, A-8) (GTAW) and ER3XX-15 (F-5, A-8); shielding gas for GTAW is argon.

  12. Gas tungsten arc and shielded metal arc welding of carbon steel. Welding procedure specification. Supplement 1. Records of procedure qualification tests

    SciTech Connect

    Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

    1986-06-01

    Procedure WPS-104-ASME-2 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for gas tungsten arc and shielded metal arc welding of carbon steels (P-1-1), in thickness range 0.25 to 1.0 inch; filler metals are E70S-3 (F-6, A-1) (GTAW) and E6010 (F-3, A-1) (SMAW): shielding gas is argon (GTAW).

  13. Effect of preheat on residual stress distributions in arc-welded mild steel plates

    SciTech Connect

    Adedayo, S.M.; Adeyemi, M.B.

    2000-02-01

    Residual stress distribution in the longitudinal and transverse directions on a 6-mm-thick arc-welded mild steel plate was experimentally examined with and without initial preheat. Stress measurements were completed by monitoring strain changes on mounted strain gauges resulting from successive milling of the welded plate specimens. Machining stresses were also compensated for by carrying out measurements of strain changes due to milling operation of a stress-free unwelded annealed mild steel plate. High tensile residual stresses exist close to the weld line in both longitudinal and transverse stresses. Maximum longitudinal residual stress values existing close to the weld line are reduced (between 50 and 75%) due to the effect of initial metal preheat of 200 C of the welded steel plate.

  14. Hybrid Laser-arc Welding of 17-4 PH Martensitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Ma, Junjie; Atabaki, Mehdi Mazar; Pillai, Raju; Kumar, Biju; Vasudevan, Unnikrishnan; Sreshta, Harold; Kovacevic, Radovan

    2015-06-01

    17-4 PH stainless steel has wide applications in severe working conditions due to its combination of good corrosion resistance and high strength. The weldability of 17-4 PH stainless steel is challenging. In this work, hybrid laser-arc welding was developed to weld 17-4 PH stainless steel. This method was chosen based on its advantages, such as deep weld penetration, less filler materials, and high welding speed. The 17-4 PH stainless steel plates with a thickness of 19 mm were successfully welded in a single pass. During the hybrid welding, the 17-4 PH stainless steel was immensely susceptible to porosity and solidification cracking. The porosity was avoided by using nitrogen as the shielding gas. The nitrogen stabilized the keyhole and inhibited the formation of bubbles during welding. Solidification cracking easily occurred along the weld centerline at the root of the hybrid laser-arc welds. The microstructural evolution and the cracking susceptibility of 17-4 PH stainless steel were investigated to remove these centerline cracks. The results showed that the solidification mode of the material changed due to high cooling rate at the root of the weld. The rapid cooling rate caused the transformation from ferrite to austenite during the solidification stage. The solidification cracking was likely formed as a result of this cracking-susceptible microstructure and a high depth/width ratio that led to a high tensile stress concentration. Furthermore, the solidification cracking was prevented by preheating the base metal. It was found that the preheating slowed the cooling rate at the root of the weld, and the ferrite-to-austenite transformation during the solidification stage was suppressed. Delta ferrite formation was observed in the weld bead as well no solidification cracking occurred by optimizing the preheating temperature.

  15. General view of blast furnace plant, with blast furnace "A" ...

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

    General view of blast furnace plant, with blast furnace "A" (built in 1907) to the left; in the foreground is the turbo-blower and blast furnace gas-powered electric generating station (built in 1919), looking northwest - Bethlehem Steel Corporation, South Bethlehem Works, Blast Furnace "A", Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

  16. 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...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

  17. Driven Motion and Instability of an Atmospheric Pressure Arc

    SciTech Connect

    Max Karasik

    1999-12-01

    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 arc 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.

  18. Thermal protection of H13 steel by growth of (TiAl)N films by PAPVD pulsed arc technique

    SciTech Connect

    Jimenez, H.; Devia, D.M.; Benavides, V.; Devia, A. Arango, Y.C.; Arango, P.J.; Velez, J.M.

    2008-08-15

    (TiAl)N Films were grown on H13 steel by a plasma assisted repetitive pulsed arc discharge. To grow the coatings, a TiAl sintered cathode was used, 50% Ti-50% Al. The deposition system consists of a reaction chamber with two electrodes placed face to face. A pulsed power supply, which allows for control of parameters like time active arc, time between arcs, arc energy, and others, is used to generate the discharge. Thermal changes were carried out on H13 steel before and after growing the (TiAl)N films. X-ray diffraction (XRD) was employed to study the coatings, observing the H13 steel and (TiAl)N oxidation temperature. Morphological characteristics were analyzed by means of an Atomic Force Microscopy (AFM). Scanning electron microscopy (SEM) revealed the surface chemical composition of the films and morphological details of the samples.

  19. 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.

  20. Underwater wet flux-cored arc welding development of stainless steel and nickel-based materials

    SciTech Connect

    Findlan, S.J.; Frederick, G.J.

    1995-12-31

    The inaccessibility and high radiation fields of components in the lower two thirds of a reactor pressure vessel (RPV) has generated the need for an automated underwater wet welding process to address repair applications. Mechanical methods presently employed for this type of repair application produce crevices, which promote concerns of intergranular stress corrosion cracking (IGSCC), crevice corrosion and pitting. To address these concerns, the EPRI Repair and Replacement Applications Center (RRAC) has developed underwater wet flux-cored arc welding (FCAW) technology for the welding of stainless steel and nickel based materials. The benefits of underwater wet welding include: (1) provides a permanent repair; (2) offers crevice-five conditions; (3) reduces future inspection requirements (4) eliminates the potential for ``loose parts`` (5) can be performed in a timely approach. Underwater wet shielded metal arc welding (SMAW) has been successfully used to repair components in radiation areas of the upper section of the RPV, although this process is a manual operation and is impractical for remote applications. The developmental work at the EPRI RRAC is directed towards remote repair applications of nickel-based and stainless steel components, which are inaccessible with normal manual repair techniques, e.g., access hole covers. The flux-cored arc welding process (FCAW) was considered a viable option for underwater development, due to the ease of automation, out of position welding proficiency and self-shielding capabilities.

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

    SciTech Connect

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

    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 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.

  2. 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.

  3. 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.

  4. Tube furnace

    SciTech Connect

    Foster, K.G.; Frohwein, E.J.; Taylor, R.W.; Bowen, D.W.

    1990-12-31

    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.

  5. Tube furnace

    SciTech Connect

    Foster, K.G.; Frohwein, E.J.; Taylor, R.W.; Bowen, D.W.

    1990-01-01

    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.

  6. Use of plasma arc welding process to combat hydrogen metallic disbonding of austenitic stainless steel claddings

    SciTech Connect

    Alexandrov, O.A. ); Steklov, O.I.; Alexeev, A.V. )

    1993-11-01

    A separation type crack, metallic disbonding, occurred between austenitic stainless steel weld metal cladding and 2 1/4Cr-1Mo base metal in the hydrodesulfurizing reactor of an oil refining plant. For stainless steel cladding, the submerged arc welding (SAW) process with a strip electrode is usually applied, but the authors experimented with the plasma arc welding (PAW) process with hot wire electrode for the cladding. The metallic disbonding is considered to be attributed to hydrogen accumulation at the transition zone and has been generally studied on a laboratory scale using an autoclave. The authors used a electrolytic hydrogen charging technique for the sake of experimental simplicity and made a comparison with the results for gaseous hydrogen charging. The main conclusions obtained were follows: The PAW stainless steel weld metal cladding is more resistant to metallic disbonding with the PAW process is explained by the desirable microstructure and properties of the first layer of weld metal at the transition zone. Electrolytic hydrogen charging pretty well reproduces the results of autoclave gas phase charging.

  7. Paired Straight Hearth Furnace - Transformational Ironmaking Process

    SciTech Connect

    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 suitable 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.

  8. Test Plan: Phase 1 demonstration of 3-phase electric arc melting furnace technology for vitrifying high-sodium content low-level radioactive liquid wastes

    SciTech Connect

    Eaton, W.C.

    1995-05-31

    This document provides a test plan for the conduct of electric arc vitrification testing by a vendor in support of the Hanford Tank Waste Remediation System (TWRS) Low-Level Waste (LLW) Vitrification Program. The vendor providing this test plan and conducting the work detailed within it [one of seven selected for glass melter testing under Purchase Order MMI-SVV-384216] is the US Bureau of Mines, Department of the Interior, Albany Research Center, Albany, Oregon. This test plan is for Phase I activities described in the above Purchase Order. Test conduct includes feed preparation activities and melting of glass with Hanford LLW Double-Shell Slurry Feed waste simulant in a 3-phase electric arc (carbon electrode) furnace.

  9. THE REMOVAL OF CARBON/BEUTERIUM FROM STAINLESS STEEL AND TUNGSTEN BY TRANSFERRED-ARC CLEANING

    SciTech Connect

    K. J. HOLLIS; R. G. CASTRO; ET AL

    2001-04-01

    Tungsten and stainless steel samples have been contaminated with deuterium and carbon to simulate deposited layers in magnetic-confinement fusion devices. Deuterium and carbon were co-deposited onto the sample surfaces using a deuterium plasma seeded with varying amounts of deuterated methane. Deuterium was also implanted into the samples in an accelerator to simulate hydrogen isotope ion implantation conditions in magnetic confinement fusion devices. Cathodic arc, or transferred-arc (TA) cleaning was employed to remove the deposits from the samples. The samples were characterized by ion beam analysis both before and after cleaning to determine deuterium and carbon concentrations present. The deuterium content was greatly reduced by the cleaning thus demonstrating the possibility of using the TA cleaning technique for removing deuterium and/or tritium from components exposed to D-T fuels. Removal of surface layers and significant reduction of subsurface carbon concentrations was also observed.

  10. 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…

  11. 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…

  12. 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% CO2 and 100% CO2. 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% 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.

  13. 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

  14. Dilution control in single-wire stainless steel submerged arc cladding

    SciTech Connect

    Kotecki, D.J.

    1996-02-01

    An experimental study of the effects of bead-to-bead stepover, wire size, wire feed speed, voltage, flux chromium content, and polarity on dilution and ferrite in single-wire submerged arc cladding of ER309L on mild steel plate is described. Low dilution was found to be promoted by reduced stepover, reduced wire feed speed, and DC electrode negative polarity. Use of a high-chromium flux can broaden the tolerance for dilution, providing an austenitic deposit free of martensite, and containing at least 4 FN for assurance of freedom from hot cracking over a broader range of dilutions.

  15. Parametric Studies Of Weld Quality Of Tungsten Inert Gas Arc Welding Of Stainless Steel

    SciTech Connect

    Kumar Pal, Pradip; Nandi, Goutam; Ghosh, Nabendu

    2011-01-17

    Effect of current and gas flow rate on quality of weld in tungsten inter gas arc welding of austenitic stainless steel has been studied in the present work through experiments and analyses. Butt welded joints have been made by using several levels of current and gas flow rate. The quality of the weld has been evaluated in terms of ultimate and breaking strengths of the welded specimens. The observed data have been interpreted, discussed and analyzed by using Grey--Taguchi methodology. Optimum parametric setting has been predicted and validated as well.

  16. Arc spraying of nano-structured wire on carbon steel: examination of coating microstructures

    SciTech Connect

    Al Askandarani, A.; Hashmi, M. S. J.; Yilbas, B. S.

    2011-01-17

    Arc spraying of nano-structured wire (TAFA 95MX) onto carbon steel is carried out. The workpieces coated were heat treated at temperature similar to the operating temperature of the hot-path components of power gas turbines. The morphological and microstructural changes in the coating are examined using optical and Scanning Electron Microscope (SEM). The surface roughness and microhardness of the resulting coatings are measured. It is found that the formation of dimples like structure at surface increased the surface roughness of the coating. The microhardness of the resulting coating is significantly higher than the base material hardness. Heat treatment does not alter the microstructure and microhardness of the coating.

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

    NASA Astrophysics Data System (ADS)

    Hashemi, S. H.; Mohammadyani, D.

    2011-01-01

    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 wall 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.

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

    SciTech Connect

    Hashemi, S. H.; Mohammadyani, D.

    2011-01-17

    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 wall 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.

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

    SciTech Connect

    Shen, Z.; Chen, Y.; Haghshenas, M.; Nguyen, T.; Galloway, J.; Gerlich, A.P.

    2015-06-15

    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 over 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.

  20. 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.

  1. Effect of Welding Consumables on Fatigue Performance of Shielded Metal Arc Welded High Strength, Q&T Steel Joints

    NASA Astrophysics Data System (ADS)

    Magudeeswaran, G.; Balasubramanian, V.; Madhusudhan Reddy, G.

    2009-02-01

    Quenched and Tempered (Q&T) steels are widely used in the construction of military vehicles due to their high strength-to-weight ratio and high hardness. These steels are prone to hydrogen-induced cracking in the heat affected zone (HAZ) after welding. The use of austenitic stainless steel consumables to weld the above steel was the only remedy because of higher solubility for hydrogen in austenitic phase. Recent studies proved that high nickel steel and low hydrogen ferritic steel consumables can be used to weld Q&T steels, which can give very low hydrogen levels in the weld deposits. In this investigation an attempt has been made to study the effect of welding consumables on high cycle fatigue properties of high strength, Q&T steel joints. Three different consumables namely (i) austenitic stainless steel, (ii) low hydrogen ferritic steel, and (iii) high nickel steel have been used to fabricate the joints by shielded metal arc (SMAW) welding process. The joints fabricated using low hydrogen ferritic steel electrodes showed superior fatigue properties than other joints.

  2. Large-Scale Evaluation of Nickel Aluminide Rools In A Heat-Treat Furnace at Bethlehem Steel's (now ISG) Burns Harbor Plate Mill

    SciTech Connect

    John Mengel; Anthony Martocci; Larry Fabina; RObert Petrusha; Ronald Chango

    2003-09-01

    At Bethlehem Steel Burns Harbor Plate Division (now ISG Burns Harbor Plate Inc.)'s annealing furnace, new nickel aluminide intermetallic alloy rolls provide greater high-temperature strength and wear resistance compared to the conventional H series cast austenitic alloys currently used in the industry, Oak Ridge National Laboratory and Bethlehem (ISG) partnered under a U.S. Department of Energy, Office of Industrial Technology's Emerging Technology Deployment Program to demonstrate and evaluate the nickel aluminide intermetallic alloy rolls as part of an updated energy efficient large commercial annealing furnace system.

  3. 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.

  4. 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.

  5. Corrosion Behavior of Pulsed Gas Tungsten Arc Weldments in Power Plant Carbon Steel

    NASA Astrophysics Data System (ADS)

    Kumaresh Babu, S. P.; Natarajan, S.

    2007-10-01

    Welding plays an essential role in fabrication of components such as boiler drum, pipe work, heat exchangers, etc., used in power plants. Gas tungsten arc welding (GTAW) is mainly used for welding of boiler components. Pulsed GTAW is another process widely used where high quality and precision welds are required. In all arc-welding processes, the intense heat produced by the arc and the associated local heating and cooling lead to varied corrosion behavior and several metallurgical phase changes. Since the occurrence of corrosion is due to electrochemical potential gradient developed in the adjacent site of a weld metal, it is proposed to study the effects of welding on the corrosion behavior of these steels. This paper describes the experimental work carried out to evaluate and compare corrosion and its inhibition in SA 516 Gr.70 carbon steel by pulsed GTAW process in HCl 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 made at room temperature (R.T.) and at 100 °C. Electrochemical polarization techniques such as Tafel line extrapolation (Tafel), linear polarization resistance (LPR), and ac impedance method 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, surface characterization, and morphology using SEM and XRD studies have been made on samples exposed at 100 °C in order to highlight the nature and extent of film formation.

  6. 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.

  7. Determination of the Effect of Current and Travel Speed of Gas Metal-Arc Welding on the Mechanical Properties of A36, A516, and A514 Steels

    DTIC Science & Technology

    1980-05-01

    Identify by block number) steel welded joints gas metal-arc welding 70. AWTRr A ass is ,eYe slob If neoemy Md identify by block numfber) This study was...impact properties of butt joint welds produced by fully automatic gas metal-arc weld - ing (GMAW) in carbon steel (A36), pressure-vessel steel (A5 16), and...with American Society for CURRENT AND TRAVEL SPEED OF GAS Testing and Materials [ASTM] A201 mild steel up to METAL-ARC WELDING ON THE MECHAN- 2 in. (51

  8. 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.

  9. Fracture properties of a neutron-irradiated stainless steel submerged arc weld cladding overlay

    SciTech Connect

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-01-01

    The ability of stainless steel cladding to increase the resistance of an operating nuclear reactor pressure vessel to extension of surface flaws depends greatly on the properties of the irradiated cladding. Therefore, weld overlay cladding irradiated at temperatures and fluences relevant to power reactor operation was examined. The cladding was applied to a pressure vessel steel plate by the submerged arc, single-wire, oscillating-electrode method. Three layers of cladding provided a thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. The type 309 was diluted considerably by excessive melting of the base plate. Specimens were taken from near the base plate-cladding interface and also from the upper layers. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to a fluence of 2 x 10/sup 23/ neutrons/m/sup 2/ (>1 MeV). 10 refs., 16 figs., 4 tabs.

  10. Large-scale Evaluation of Nickel Aluminide Rolls in a Heat-Treat Furnace at Bethelehem Steel's (Now ISG) Burns Harbor Plate Mill

    SciTech Connect

    Mengel, J.

    2003-12-16

    At Bethlehem Steel Burns Harbor Plate Division (now ISG Burns Harbor Plate Inc.)'s annealing furnace, new nickel aluminide intermetallic alloy rolls provide greater high-temperature strength and wear resistance compared to the conventional H series cast austenitic alloys currently used in the industry. Oak Ridge National Laboratory and Bethlehem (ISG) partnered under a U.S. Department of Energy, Office of Industrial Technology's Emerging Technology Deployment Program to demonstrate and evaluate the nickel aluminide intermetallic alloy rolls as part of an updated energy efficient large commercial annealing furnace system. Many challenges were involved in this project, including developing welding procedures for joining nickel aluminide intermetallic alloys with H-series austenitic alloys, developing commercial cast roll manufacturing specifications, working with several commercial suppliers to produce a quantity of high quality, reproducible nickel aluminide rolls for a large steel industrial annealing furnace, installing and demonstrating the capability of the rolls in this furnace, performing processing trials to evaluate the benefits of new equipment and processes, and documenting the findings. Updated furnace equipment including twenty-five new automated furnace control dampers have been installed replacing older design, less effective units. These dampers, along with upgraded flame-safety control equipment and new AC motors and roll-speed control equipment, are providing improved furnace control and additional energy efficiency. Energy data shows up to a 34% energy reduction from baseline after the installation of upgraded furnace damper controls along with up to a 34% reduction in greenhouse gases, potential for an additional 3 to 6% energy reduction per campaign of light-up and shutdown, and a 46% energy reduction from baseline for limited trials of a combination of improved damper control and straight-through plate processing. The straight-through processing

  11. Energy audit of three energy-conserving devices in a steel-industry demonstration program. Task I. Hague forge furnaces. Final report

    SciTech Connect

    Lownie, H.W.; Holden, F.C.

    1982-06-01

    A program to demonstrate to industry the benefits of installing particular types of energy-conserving devices and equipment was carried out. One of these types of equipment and the results obtained under production conditions in commercial plants are described. The equipment under consideration includes improved forge furnaces and associated heat-recovery components. They are used to heat steel to about 2300 F prior to hot forging. The energy-conserving devices include improved insulation, automatic air-fuel ratio control, and a ceramic recuperator that recovers heat from hot combustion gases and delivers preheated air to high-temperature recirculating burners. Twelve Hague furnaces and retrofit packages were purchased and installed by eleven host forge shops that agree to furnish performance data for the purpose of demonstrating the energy and economic savings that can be achieved in comparison with existing equipment. Fuel savings were reported by comparing the specific energy consumption (Btu's per pound of steel heated) for each Hague furnace with that of a comparison furnace. Economic comparisons were made using payback period based on annual after-tax cash flow. Payback periods for the Hague equipment varied from less than two years to five years or more. In several cases, payback times were high only because the units were operated at a small fraction of their available capacity.

  12. Split Heat Mechanical Property Comparison of ESR (Electroslag Remelting) and VAR (Vacuum Arc Remelting) 4340 Steel. Revised

    DTIC Science & Technology

    1983-05-01

    34· AMMRC TR 83-27 (Revised) lAD SPLIT HEAT MECHANICAL PROPERTY COMPARISON OF ESR AND VAR 4340 STEEL CHARI£S F. HICKEY, Jr. and ALBERT A...COIIEREO SPLIT HEAT MECHANICAL PROPERTY COMPARISON OF Final Report ESR AND VAR 4340 STEEL ’ PERFORMING ORG. REPORT NU1118ER 7. AU THOA(•I •• CONTRACT...decarburized (AOD) heat of 4340 steel which was further pro- cessed by vacuum arc remelting (VAR) and electroslag remelting ( ESR ) into 12.7 em (5 inch) square

  13. Bare carbon steel electrodes and fluxes for submerged arc welding (ASME SFA-5. 17 with additional requirements)

    SciTech Connect

    Not Available

    1982-08-01

    This standard covers bare carbon steel electrodes and fluxes for submerged arc welding in nuclear and associated applications. Material shall conform to the requirements of ASME SFA-5.17; to the requirements of the ASME Boiler and Pressure Vessel Code (ASME Code), Section III, Article NB-2000; and to the additional requirements of this standard.

  14. Non-invasive magnetopneumographic determination of lung dust loads in steel arc welders.

    PubMed Central

    Freedman, A P; Robinson, S E; O'Leary, K; Goodman, L; Stellman, J M

    1981-01-01

    Magnetopneumography was used to measure non-invasively the concentration of the ferrimagnetic fraction of retained welding fume in the thoraces of steel arc welders. This was done by measuring the remanent magnetic fields due to ferrimagnetic particles. The 11 welders studied had concentrations of thoracic ferrimagnetic mineral several orders of magnitude greater than three machinists, 16 former asbestos insulators and 24 control subjects. These concentrations correlated well with total years welding (p less than 0.01) and radiographic evidence of small rounded densities (p less than 0.05), but not with smoking history. There was a higher concentration of ferrimagnetic mineral over the hilar regions. Magnetopneumography offers a non-invasive indicator of the accumulation of welding fume in the thorax. PMID:7317303

  15. 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.

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

    SciTech Connect

    Campbell, R.D.; Heiple, C.R.; Sturgill, P.L.; Robertson, A.M.; Jamsay, R.

    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, and 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.

  17. Microsegregation in high-molybdenum austenitic stainless steel laser beam and gas tungsten arc welds

    SciTech Connect

    Kujanpaeae, V.P.; David, S.A.

    1986-01-01

    An austenitic stainless steel with 6% molybdenum (thickness 6 mm) was welded using laser beam (LB) and gas tungsten arc (GTA) processes at various welding speeds. Depending on the welding speed the primary dendrite spacing ranged from 12 to 17 ..mu..m and from 2 to 7 ..mu..m for the GTA and LB welds, respectively. Extensive segregation of molybdenum was observed in the GTA welds. The segregation ratio for molybdenum, C/sub ID//C/sub D/, was found to be 1.9 in the GTA weld, and 1.2 in the LB weld. Distribution of iron, chromium and nickel was found nearly uniform in both welds. A recovered microstructure was observed after a post-weld annealing heat treatment. Annealing had a profound effect on the molybdenum segregation ratio in the laser weld. The critical pitting temperature (CPT) determined by a standard test was 55/sup 0/C for welds made using both processes, whereas it was 75/sup 0/C for the base metal. Upon homogenization the CPT of the laser beam weld increased to the base metal value, while that of the gas tungsten arc weld remained at 60/sup 0/C.

  18. Dilution control in single-wire stainless steel submerged arc cladding

    SciTech Connect

    Kotecki, D.J., Ogborn, J.S.

    1994-12-31

    Work by Jackson and others has shown that dilution of single weld beads can be controlled to a limited extent by choice of welding parameters in single wire submerged arc overlay. Inquiries from fabricators about limiting dilution in single-wire submerged arc cladding continue to be received. Accordingly, a procedure development program was undertaken to provide technical support to fabricators. A table, with a lead screw for accurately and reproducibly indexing the stepover from bead to bead, was constructed. Overlays, at least eight beads wide, were deposited on 1-in. thick mild steel using ER309L wire, in sizes 1/8, 3/32, and 5/64- in. More than 50 different cladding conditions have been examined. A number of overlays were made with 1/8 in. wire at 80 ipm wire feed speed (about 16.5 lb/h deposition rate), DCEP, with a chromium-compensating flux. Voltage, tilt of the electrode back towards the previous bead, and stepover were principle variables. In single-wire submerged arc cladding with ER309L, stepover is a very important variable in determining dilution and ferrite. However, if too little stepover is used, lack of fusion of the overlay with the base metal results. Use of DCEN can be helpful in limiting dilution and obtaining ferrite, but many fluxes do not perform well on DCEN. A chromium-adding flux designed for DCEN can be of assistance in limiting dilution and obtaining ferrite over a broader range of stepovers. Quantitative dilution data are presented for a variety of single-layer overlay conditions.

  19. 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.

  20. 1020 steel coated with Ti/TiN by Cathodic Arc and Ion Implantation

    NASA Astrophysics Data System (ADS)

    Bermeo, F.; Quintana, J. P.; Kleiman, A.; Sequeda, F.; Márquez, A.

    2017-01-01

    TiN coatings have been widely studied in order to improve mechanical properties of steels. In this work, thin Ti/TiN films were prepared by plasma based immersion ion implantation and deposition (PBII&D) with a cathodic arc on AISI 1020 steel substrates. Substrates were exposed to the discharge during 1 min in vacuum for the deposition of a Tiunderlayer with the aim of improving the adhesion to the substrate. Then, a TiN layer was deposited during 6 min in a nitrogen environment at a pressure of 3xl0-4 mbar. Samples were obtained at room temperature and at 300 °C, and with or without ion implantation in order to analyze differences between the effects of each treatment on the tribological properties. The mechanical and tribological properties of the films were characterized. The coatings deposited by PBII&D at 300 °C presented the highest hardness and young modulus, the best wear resistance and corrosion performance.

  1. 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).

  2. 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.

  3. Effect of Post-Welding Heat Treatment on Mechanical Properties of Joints of Steel P92 Formed by Submerged Arc Welding

    NASA Astrophysics Data System (ADS)

    Mohyla, P.; Foldynová, K.

    2014-07-01

    Results of mechanical tests and metallographic studies of welded joints of steel P92 obtained by submerged arc welding are presented. The effect of the post-welding heat treatment on the mechanical properties of the welds is described.

  4. Looking southwest at blast furnaces no. 5 and no. 6 ...

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

    Looking southwest at blast furnaces no. 5 and no. 6 with blast furnace trestle and Gondola Railroad cars in foreground. - U.S. Steel Edgar Thomson Works, Blast Furnace Plant, Along Monongahela River, Braddock, Allegheny County, PA

  5. 41. Casting floor, "B" furnace, pour in progress; mudgun is ...

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

    41. Casting floor, "B" furnace, pour in progress; mudgun is to right of furnace; photo taken from furnace operator's booth. Looking south/southwest - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  6. Looking southeast at blast furnaces no. 5 and no. 6 ...

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

    Looking southeast at blast furnaces no. 5 and no. 6 with blast furnace trestle and Gondola Railroad cars in foreground. - U.S. Steel Edgar Thomson Works, Blast Furnace Plant, Along Monongahela River, Braddock, Allegheny County, PA

  7. INTERIOR VIEW LOOKING WEST, CAST HOUSE OF BLAST FURNACE NO. ...

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

    INTERIOR VIEW LOOKING WEST, CAST HOUSE OF BLAST FURNACE NO. 1 AND BLAST FURNACE NO. 2. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

  8. 56. LOOKING NORTH AT DOROTHY SIX BLAST FURNACE WITH CAST ...

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

    56. LOOKING NORTH AT DOROTHY SIX BLAST FURNACE WITH CAST HOUSE IN FOREGROUND AND DUSTCATCHER AT RIGHT OF FURNACE (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  9. 3. VIEW OF DUQUESNE'S RAIL LINES AND BLAST FURNACE PLANT ...

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

    3. VIEW OF DUQUESNE'S RAIL LINES AND BLAST FURNACE PLANT LOOKING NORTH. DOROTHY SIX IS THE CLOSEST FURNACE IN THE PHOTOGRAPH. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  10. 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

  11. 50. Taken from highline; "B" furnace slag pots, pipe is ...

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

    50. Taken from high-line; "B" furnace slag pots, pipe is main blast furnace gas line from "C" furnace dust catcher; levy, slag hauler, removing slag. Looking east - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  12. Tensile and Impact Toughness Properties of Gas Tungsten Arc Welded and Friction Stir Welded Interstitial Free Steel Joints

    NASA Astrophysics Data System (ADS)

    Lakshminarayanan, A. K.; Balasubramanian, V.

    2011-02-01

    Welded regions of interstitial free (IF) steel grades in the vicinity of weld center exhibits larger grains because of the prevailing thermal conditions during weld metal solidification. This often causes inferior weld mechanical properties. In the present study, tensile properties, charpy impact toughness, microhardness, microstructure, lowest hardness distribution profile, and fracture surface morphology of the gas tungsten arc welded (GTAW) and friction stir welded joints were evaluated, and the results are compared. From this investigation, it is found that friction stir welded joint of IF steel showed superior tensile and impact properties compared with GTAW joint, and this is mainly due to the formation of very fine, equiaxed microstructure in the weld zone.

  13. 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.

  14. 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.

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

    SciTech Connect

    Lim, Yong Chae; Sanderson, Samuel; Mahoney, Murray; Wasson, Andrew J; Fairchild, Doug P; Wang, Yanli; Feng, Zhili

    2015-01-01

    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. To 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.

  16. 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.

  17. 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

  18. Workplace exposure to submicron particle mass and number concentrations from manual arc welding of carbon steel.

    PubMed

    Stephenson, Dale; Seshadri, Gauri; Veranth, John M

    2003-01-01

    Particle emissions from manual shielded metal arc welding of carbon steel were sampled in a typical industrial maintenance and metal fabrication workplace environment. Particle number measurements over the size range from 14 nm to 10 microm using a scanning mobility particle sizer and an optical particle counter showed that welding produced an approximately lognormal particle mode with a 120 nm count median and a geometric standard deviation of 2.07. This study produced welding particle number concentrations on the order of 2 x 10(5)/cm(3) in the building air 8.5 m away from the welding. Workplace exposure samples were below the current 8-hour American Conference of Governmental Industrial Hygienists mass concentration threshold limit value of 5 mg/m(3). Submicron particles comprised 80% of the total aerosol mass collected by a cascade impactor during welding. The concentration of larger particles was indistinguishable from indoor background. Microscopy showed that the welding emissions are dominated by clusters formed from <0.1 microm primary spheres. These data on the particles resulting from aerosol transformation by natural dilution inside an industrial building can be compared with laboratory-scale studies of welding particulate. The particle number characteristics observed in this study are significant because toxicological hypotheses suggest that number or surface area may be a better metric than mass when evaluating the health effects of fine particles.

  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. 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.

  1. 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.

  2. Microstructure, Texture, and Mechanical Property Analysis of Gas Metal Arc Welded AISI 304 Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Saha, Saptarshi; Mukherjee, Manidipto; Pal, Tapan Kumar

    2015-03-01

    The present study elaborately explains the effect of welding parameters on the microstructure, texture, and mechanical properties of gas metal arc welded AISI 304 austenitic stainless steel sheet (as received) of 4 mm thickness. The welded joints were prepared by varying welding speed (WS) and current simultaneously at a fixed heat input level using a 1.2-mm-diameter austenitic filler metal (AISI 316L). The overall purpose of this study is to investigate the effect of the variation of welding conditions on: (i) Microstructural constituents using optical microscope and transmission electron microscope; (ii) Micro-texture evolution, misorientation distributions, and grain boundaries at welded regions by measuring the orientation data from electron back scattered diffraction; and (iii) Mechanical properties such as hardness and tensile strength, and their correlation with the microstructure and texture. It has been observed that the higher WS along with the higher welding current (weld metal W1) can enhance weld metal mechanical properties through alternation in microstructure and texture of the weld metal. Higher δ-ferrite formation and high-angle boundaries along with the <101> + <001> grain growth direction of the weld metal W1 were responsible for dislocation pile-ups, SFs, deformation twinning, and the induced martensite with consequent strain hardening during tensile deformation. Also, fusion boundary being the weakest link in the welded structure, failure took place mainly at this region.

  3. A Kinetic Ladle Furnace Process Simulation Model: Effective Equilibrium Reaction Zone Model Using FactSage Macro Processing

    NASA Astrophysics Data System (ADS)

    Van Ende, Marie-Aline; Jung, In-Ho

    2017-02-01

    The ladle furnace (LF) is widely used in the secondary steelmaking process in particular for the de-sulfurization, alloying, and reheating of liquid steel prior to the casting process. The Effective Equilibrium Reaction Zone model using the FactSage macro processing code was applied to develop a kinetic LF process model. The slag/metal interactions, flux additions to slag, various metallic additions to steel, and arcing in the LF process were taken into account to describe the variations of chemistry and temperature of steel and slag. The LF operation data for several steel grades from different plants were accurately described using the present kinetic model.

  4. 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.

  5. Activated electric arc furnace slag as an effective and reusable Fenton-like catalyst for the photodegradation of methylene blue and acid blue 29.

    PubMed

    Nasuha, N; Ismail, S; Hameed, B H

    2017-07-01

    In this work, an activated electric arc furnace slag (A-EAFS) was investigated as an effective Fenton catalyst for the photodegradation of methylene blue (MB) and acid blue 29 (AB29). Fourier transform infrared spectroscopy and UV-visible absorption analyses indicated that A-EAFS offers additional Fe3O4 because of the changes in the iron oxide phase and the favorable response to visible light. It has been found that the highest degradation efficiency can reach up to 94% for MB under optimal conditions of 1 g L(-1) of A-EAFS, 20 mM H2O2, and pH 3. The optimal conditions for AB29 were 0.1 g L(-1) A-EAFS, 4 mM H2O2, and pH 3 to reach 98% degradation efficiency. Visible light enhanced the degradation of both dyes. In addition, A-EAFS, could be easily separated magnetically, exhibited good chemical stability after seven successive photodegradation cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Synthesis of TiO2 visible light catalysts with controllable crystalline phase and morphology from Ti-bearing electric arc furnace molten slag.

    PubMed

    Li, Yang; Liu, Lulu; Guo, Min; Zhang, Mei

    2016-09-01

    TiO2 visible light catalysts with different crystalline phases and morphologies were synthesized from titanium-bearing electric arc furnace molten slag (Ti-bearing EAF slag) by using a simple acidolysis process. The effects of the pH of the HCl solution, liquid to solid ratio (RL/S, HCl solution to the residue ratio, mL/g) and acidolysis time on the micro-morphology and crystalline phase of as-prepared TiO2 photocatalysts were systematically investigated. The results indicated that with decreasing pH in the HCl solution and increasing RL/S, the crystalline phase and micro-morphology of the obtained TiO2 nanostructures tended to transform from anatase type TiO2 with spherical nanoparticle structures to rutile type TiO2 with needle-like nanorod structures. The acidolysis time had little influence on the crystalline phase but great impact on the size of the obtained TiO2. The growth mechanism of TiO2 from Ti-bearing EAF slag during the acidolysis process was also discussed. In addition, the influence of RL/S on the photocatalytic properties of the synthesized nanostructured TiO2 was studied. The results showed that the photodegradation efficiency for Rhodamine B solution could reach 91.00% in 120min when the RL/S was controlled at 50:1. Copyright © 2016. Published by Elsevier B.V.

  7. On the distribution and bonding environment of Zn and Fe in glasses containing electric arc furnace dust: a mu-XAFS and mu-XRF study.

    PubMed

    Pinakidou, F; Katsikini, M; Paloura, E C; Kavouras, P; Kehagias, Th; Komninou, Ph; Karakostas, Th; Erko, A

    2007-04-02

    We apply synchrotron radiation assisted X-ray fluorescence (SR-XRF), SR-XRF mapping as well as micro- and conventional X-ray absorption fine structure (mu-XAFS and XAFS) spectroscopies in order to study the bonding environment of Fe and Zn in vitrified samples that contain electric arc furnace dust from metal processing industries. The samples are studied in the as-cast state as well as after annealing at 900 degrees C. The SR-XRF results demonstrate that annealing does not induce any significant changes in the distribution of either Fe or Zn, in both the as-cast and annealed glasses. The mu-XAFS spectra recorded at the Fe-K and Zn-K edges reveal that the structural role of both Fe and Zn remains unaffected by the annealing procedure. More specifically, Fe forms both FeO(6) and FeO(4) polyhedra, i.e. acts as an intermediate oxide while Zn occupies tetrahedral sites.

  8. Chemical characterization of dust particles recovered from bag filters of electric arc furnaces for steelmaking: some factors influencing the formation of hexachlorobenzene.

    PubMed

    Tsubouchi, Naoto; Hashimoto, Hiroyuki; Ohtaka, Noriaki; Ohtsuka, Yasuo

    2010-11-15

    To make clear some factors controlling the formation of hexachlorobenzene (HCB) in the process of electric arc furnace (EAF) steelmaking, six dust samples recovered from different bag filters in commercial EAF steelmaking plants have been characterized with XRD, SEM-EPMA, XPS and temperature-programmed desorption (TPD) techniques. These dust samples contain 1.9-8.0 mass% of chlorine element, and the XPS and TPD measurements exhibit that the Cl is enriched at the dust surface and composed of the inorganic and organic functionalities, part of the Cl being evolved as HCl in the temperature region of flue gas treatment. All of the samples also include 2.1-6.4 mass% of carbon element, and some of the C can release CO(2) in the TPD up to 300°C to form active carbon sites. The number is related closely to HCB concentration of each dust. Further, it is suggested that the Zn present in the samples consists of ZnFe(2)O(4), ZnO and surface ZnCO(3), and the dust with a larger content of the ZnCO(3) has a higher concentration of HCB. It is possible that HCB formation occurs via gas-solid-solid interactions among gaseous Cl-containing compounds in flue gas, active carbon sites and surface Zn-species produced in exhaust ducts and bag filters.

  9. 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

  10. Gas carburizing of steel with furnace atmospheres formed in situ from methane and air and from butane and air

    NASA Astrophysics Data System (ADS)

    Stickels, C. A.; Mack, C. M.; Pieprzak, J. A.

    1992-01-01

    Carburizing experiments were conducted at 927 °C (1700 °F) and 843 °C (1550 °F) using furnace atmospheres formed from methane and air and from butane and air introduced directly into the carburizing furnace. Gas flow rates were low to promote equilibration of the reaction products within the furnace. The air flow rate was held constant while the methane or butane flow was automatically regulated to maintain a constant oxygen potential, as measured by a zirconia oxygen sensor, within the furnace. In comparing the results of these experiments with earlier results obtained using propane and air, several differences were noted: (a) The methane content of the furnace atmosphere, measured by infrared analysis, was about twice as great when methane was the feed gas rather than propane or butane. This was true despite the fact that the mean residence time of the gas within the furnace was greater in the methane experiments. Methane appears to be less effective than propane or butane in reducing the CO2 and H2O contents to the levels required for carburizing. (b) There was a greater tendency for the CO content of the furnace atmosphere to decrease at high carbon potentials when methane is used instead of propane or butane. The decrease in CO content is due to hydrogen dilution caused by sooting in the furnace vestibule. These differences in behavior make propane or butane better suited than methane for in situ generation of carburizing atmospheres. However, there is no difference in the amount of carburizing occurring at a specified carbon potential when methane, propane, or butane are used as the feed gas in this process.

  11. 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.

  12. 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.

  13. 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

  14. Correlation of inclusion size and chemistry with weld metal composition and microstructure arc weldments of high strength steels

    NASA Astrophysics Data System (ADS)

    Eakes, Mark W.

    1994-12-01

    Non-metallic inclusions are crucial to the development of acicular ferrite, the desired microstructure for optimal strength and toughness in weld metal. This study focused on obtaining correlation between the size and chemistry of inclusions and weld metal properties, especially the amount of acicular ferrite, in Gas Metal Arc (GMA) and Submerged Arc (SA) weldments in HY-100 and HSLA-100 steel. A strong correlation was found between the amount of acicular ferrite, flux basicity and inclusion composition and volume fraction in SAW weld metal samples. An index developed to consider the effect of chemistry and volume fraction of inclusions on acicular ferrite showed good correlation. The GMA weld samples were found to contain less acicular ferrite than the SAW samples, principally because of their lower oxygen content. However, it was again found possible to correlate inclusion chemistry and volume fraction with acicular ferrite formation. Unfortunately, the large amount of data scatter precluded the development of an index in this case.

  15. Characterisation of the sintering behaviour of Waelz slag from electric arc furnace (EAF) dust recycling for use in the clay ceramics industry.

    PubMed

    Quijorna, N; de Pedro, M; Romero, M; Andrés, A

    2014-01-01

    Waelz slag is an industrial by-product from the recovery of electric arc furnace (EAF) dust which is mainly sent to landfills. Despite the different chemical and mineralogical compositions of Waelz slag compared to traditional clays, previous experiments have demonstrated its potential use as a clay substitute in ceramic processes. Indeed, clayey products containing Waelz slag could improve mechanical and environmental performance, fixing most of the metallic species and moreover decreasing the release of some potential pollutants during firing. However, a deeper understanding of the complex phase transformations during its thermal treatment and the connection of this behaviour with the end properties is desirable in order to explain the role that is played by the Waelz slag and its potential contribution to the ceramic process. For this purpose, in the present study, the chemical, mineralogical, thermal and environmental behaviour of both (i) unfired powdered samples, and (ii) pressed specimen of Waelz slag fired up to different temperatures within the typical range of clay based ceramic production, has been studied. The effect of the heating temperature on the end properties of the fired samples has been assessed. In general, an increase of the firing temperature promotes sintering and densification of the products and decreases the open porosity and water absorption which also contributes to the fixation of heavy metals. On the contrary, an increase in the leaching of Pb, Cr and Mo from the fired specimens is observed. This can be attributed to the creation of Fe and Ca molybdates and chromates that are weakly retained in the alkali matrix. On the other side, at temperature above 950 °C a weight gain related to the emission of evolved gases is observed. In conclusion, the firing temperature of the ceramic process is a key parameter that affects not only the technical properties but also strongly affects the leaching behaviour and the process emissions.

  16. [Inhalation exposure to welding fumes of arc welders in processing Cr-Ni steel in large chemical industry].

    PubMed

    Dyrba, B C; Richter, K H

    1989-05-01

    For clearing up the inhalative load by welding fumes and gases of arc welders in industrial workshops mainly working on Cr-Ni-steels the following welding processes were studied: tungsten inert-gas (TIG), electrode-by-hand (EH), metal inert-gas (MIG), and plasma cutting (plasma). From the total load by welding fumes follows the rank TIG less than EH less than plasma less than MIG. Observing the maximum allowable concentration (MACD) for the total welding fume, no MACD for Cr and Ni was found exceeded. Regarding the welding gases ozone and CO no limit values were exceeded. From the results conclusions were made.

  17. Blast furnace injection symposium: Proceedings

    SciTech Connect

    1996-12-31

    These proceedings contain 14 papers related to blast furnace injection issues. Topics include coal quality, coal grinding, natural gas injection, stable operation of the blast furnace, oxygen enrichment, coal conveying, and performance at several steel companies. All papers have been processed separately for inclusion on the data base.

  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. Welding fumes from stainless steel gas metal arc processes contain multiple manganese chemical species.

    PubMed

    Keane, Michael; Stone, Samuel; Chen, Bean

    2010-05-01

    Fumes from a group of gas metal arc welding (GMAW) processes used on stainless steel were generated using three different metal transfer modes and four different shield gases. The objective was to identify and measure manganese (Mn) species in the fumes, and identify processes that are minimal generators of Mn species. The robotic welding system was operated in short-circuit (SC) mode (Ar/CO2 and He/Ar), axial spray (AXS) mode (Ar/O2 and Ar/CO2), and pulsed axial-spray (PAXS) mode (Ar/O2). The fumes were analyzed for Mn by a sequential extraction process followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis, and by X-ray diffraction (XRD). Total elemental Mn, iron (Fe), chromium (Cr) and nickel (Ni) were separately measured after aqua regia digestion and ICP-AES analysis. Soluble Mn2+, Fe2+, Fe3+, and Ni2+ in a simple biological buffer (phosphate-buffered saline) were determined at pH 7.2 and 5.0 after 2 h incubation at 37 C by ion chromatography. Results indicate that Mn was present in soluble form, acid-soluble form, and acid-soluble form after reduction by hydroxylamine, which represents soluble Mn0 and Mn2+ compounds, other Mn2+ compounds, and (Mn3+ and Mn4+) compounds, respectively. The dominant fraction was the acid-soluble Mn2+ fraction, but results varied with the process and shield gas. Soluble Mn mass percent in the fume ranged from 0.2 to 0.9%, acid-soluble Mn2+ compounds ranged from 2.6 to 9.3%, and acid plus reducing agent-soluble (Mn3+ and Mn4+) compounds ranged from 0.6 to 5.1%. Total Mn composition ranged from 7 to 15%. XRD results showed fumes had a crystalline content of 90-99% Fe3O4, and showed evidence of multiple Mn oxides, but overlaps and weak signals limited identification. Small amounts of the Mn2+ in the fume (<0.01 to ≈ 1% or <0.1 to ≈ 10 microg ml(-1)) and Ni2+ (<0.01 to ≈ 0.2% or <0.1 to ≈ 2 mg ml(-1)) ions were found in biological buffer media, but amounts were highly dependent on pH and the

  20. Hybrid laser-arc welding of galvanized high-strength steels in a gap-free lap-joint configuration

    NASA Astrophysics Data System (ADS)

    Yang, Shanglu

    In order to meet the industry demands for increased fuel efficiency and enhanced mechanical and structural performance of vehicles as well as provided excellent corrosion resistance, more and more galvanized advanced high-strength steels (AHSS) have been used to fabricate automobile parts such as panels, bumpers, and front rails. The automotive industry has shown tremendous interest in using laser welding to join galvanized dual phase steels because of lower heat input and higher welding speed. However, the laser welding process tends to become dramatically unstable in the presence of highly pressurized zinc vapor because of the low boiling point of zinc, around 906°C, compared to higher melting point of steel, over 1500°C. A large number of spatters are produced by expelling the liquid metal from the molten pool by the pressurized zinc vapor. Different weld defects such as blowholes and porosities appear in the welds. So far, limited information has been reported on welding of galvanized high strength dual-phase steels in a gap-free lap joint configuration. There is no open literature on the successful attainment of defect-free welds from the laser or hybrid welding of galvanized high-strength steels. To address the significant industry demand, in this study, different welding techniques and monitoring methods are used to study the features of the welding process of galvanized DP steels in a gap-free lap joint configuration. The current research covers: (i) a feasibility study on the welding of galvanized DP 980 steels in a lap joint configuration using gas tungsten arc welding (GTAW), laser welding, hybrid laser/arc welding with the common molten pool, laser welding with the assistance of GTAW preheating source and hybrid laser-variable polarity gas tungsten arc welding (Laser-VPGTAW) techniques (Chapter 2-4); (ii) a welding process monitoring of the welding techniques including the use of machine vision and acoustic emission technique (Chapter 5); (iii

  1. Development of Efficient Recycling System for Steel Alloying Elements in End of Life Vehicles

    NASA Astrophysics Data System (ADS)

    Ohno, Hajime; Matsubae, Kazuyo; Nakajima, Kenichi; Nakamura, Shinichiro; Nagasaka, Testsuya

    Special steels, which have been imparted various properties by the addition of alloying elements, have become increasingly important as materials for human life in recent years. As the largest industrial consumer of special steel materials, the motor vehicle industry requires large volumes of various types of special steel for vehicle production. Scrap containing base metals and alloying elements is generated from end-of-life vehicles (ELVs). In current scrap treatment processes, alloying elements in steel materials are rarely considered, instead becoming impurities in steel recycling processes at electric arc furnaces (EAF) and losing their worth.

  2. Vacuum Melting of Refractory Metals and Alloys in Lining Furnaces (Chapter VI),

    DTIC Science & Technology

    Melting, *Refractory metals, *Refractory metal alloys, Vacuum furnaces, Linings, Electric arcs, Crucibles, Titanium alloys, Safety, Arc melting, Electron beam melting , Plasmas(Physics), Heating, Translations, USSR

  3. 78 FR 79667 - Stainless Steel Sheet and Strip in Coils From Japan: Initiation of Expedited Changed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-31

    ....020 percent or less. The product is manufactured by means of vacuum arc remelting, with inclusion.... Certain electrical resistance alloy steel is also excluded from the scope of this order. This product is... industrial furnaces, and in rheostats for railway locomotives. The product is currently available under...

  4. Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds

    NASA Astrophysics Data System (ADS)

    Amanie, James

    The effects of submerged arc welding (SAW) current and speed on the microstructures of SA516 grade 70 and A709 grade 50 steel welds were studied in this research. Steel plates 17 mm-thick were submerged arc welded using different welding currents (from 700 to 850 A) and welding speeds (from 5.3 to 15.3 mm/s). The effect of heat input on the weld metal chemistry, morphologies and chemistry of inclusions and nucleation of acicular ferrite (AF), grain boundary ferrite (GBF) and Widmanstatten ferrite (WF) were evaluated. Optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) microanalysis and transmission electron microscopy (TEM) were used to examine the microstructures of the developed weld joints. PAX-it image analysis software program was utilized for quantitative analysis of the microstructures. The results showed that it is difficult to ascribe changes in the microstructure that occurred in the heat affected zone (HAZ) and the weld metal regions to a single welding process parameter. Inclusion analysis revealed two types of inclusions formed in the weld metals for both steels. They are spherical and faceted inclusions. It was also observed that acicular ferrite nucleated only on the spherical inclusions. EDS analysis showed that the two inclusions have different chemical compositions. The results further showed that the total oxygen content of the weld metals of both steels generally increased with welding current, but decreased with increasing welding speed. The prior austenite grain width decreased with increasing welding speed, but increased with increasing welding current (increased heat input). For both SA516 and A709 steel welds, the proportion of acicular ferrite (AF) in the weld metals increased initially, while those of grain boundary ferrite (GBF) and Widmanstatten ferrite (WF) decreased with increasing welding current when welding current was increased from 700 A to 800 A. With further increase in the

  5. A sensing torch for on-line monitoring of the gas tungsten arc welding process of steel pipes

    NASA Astrophysics Data System (ADS)

    Ancona, Antonio; Lugarà, Pietro Mario; Ottonelli, Fabio; Catalano, Ida Maria

    2004-12-01

    Non-intrusive and real-time monitoring techniques are increasingly required by manufacturing industry in order to detect flaws in arc welding processes. In this work the development of an optical inspection system, for monitoring the manual gas tungsten arc welding (GTAW) process of steel pipes, is described. The arc plasma visible emission produced during the process was acquired and spectroscopically analysed. Measuring the intensities of selected argon emission lines allowed real time calculation and recording of the axial electron temperature of the plasma. Experimental results showed that the temperature signal varies greatly in the case of instabilities of the weld pool that cause weld defects. A suitable algorithm, based on a statistical analysis of the signal, was developed in order to real time flag defective joints. It is shown that several weld defects such as porosity, dropout, lack of fusion, solid inclusions and craters were successfully detected in a production environment. The performances of the optical sensor were compared with the results of state-of-the-art post-weld controls such as x-rays and penetrating dyes, showing good agreement and thus demonstrating the validity of this quality monitoring system.

  6. Exposure assessment of workers to airborne PCDD/Fs, PCBs and PAHs at an electric arc furnace steelmaking plant in the UK.

    PubMed

    Aries, Eric; Anderson, David R; Fisher, Raymond

    2008-06-01

    Occupational exposure studies were undertaken at a UK electric arc furnace (EAF) steelmaking plant to investigate the exposure of workers via inhalation to dioxins, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene (B[a]P). Surveys were undertaken in areas including the melting shop, the casting department and a furnace control cabin. The highest concentrations of dioxins and PCBs were found inside the melting shop nearby EAFs, whereas dioxin and PCB concentrations in the casting department and inside the control cabin were significantly lower. Risk characterization was carried out by comparing the daily intake of dioxins and PCBs through inhalation with the recommended tolerable daily intake (TDI). Health risk assessments were also carried out by combining exposure data with inhalation cancer potency factors to quantify the cancer risk. For the most exposed category of workers (melting shop workers), the estimated daily intake via inhalation was 0.35 pg WHO-TEQ kg(-1) body weight (bw) in the worst case scenario. Considering that the average UK adult exposure to dioxins from the diet is 1.8 pg WHO-TEQ kg(-1) bw day(-1), the results indicated that the estimated daily intake of dioxins via inhalation at the EAF would not result in the recommended range of the TDI (1-4 pg WHO-TEQ kg(-1) bw day(-1)) being exceeded. Cancer risks for a 40-year occupational exposure period were determined by multiplying the inhalation dose by the inhalation cancer potency factor for 2,3,7,8-tetrachlorodibenzo-p-dioxin. For melting shop workers, cancer risks from exposure to dioxins and PCBs ranged from 2.05 x 10(-5) to 7.54 x 10(-5). Under most regulatory programmes, excess cancer risks between 1.0 x 10(-4) and 1.0 x 10(-6) indicate an acceptable range of excess cancer risk, suggesting a limited risk from dioxin exposure for workers in the EAF plant. For the calculation of excess cancer risks, no account has been taken of the protection

  7. 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.

  8. Release of H and He from TiC, stainless steel and graphite by pulsed electron and furnace heating

    SciTech Connect

    Picraux, S.T.; Wampler, W.R.

    1980-01-01

    The release of implanted D and /sup 3/He from TiC coatings, SS 304 and graphite by pulsed electron beam (e-beam) heating and furnace heating has been investigated. Low fluence implants of D or /sup 3/He and saturation fluence D implants have been studied for 0.5 - 1.5 keV D and 3 keV /sup 3/He. The retained D or /sup 3/He was monitored by ion beam analysis. The 50 ns e-beam pulsing resulted in the release of D in all materials and was compared with release during isochronal annealing in a furnace. A substantial enhancement in the fractional D release was found for D saturated TiC (0.25 D to host atom ratio) compared with low fluence implants. In contrast no enhancement of D release was observed for D saturated graphite and SS 304 compared with low fluence implants. Release of /sup 3/He from TiC was also obtained by e-beam pulsed heating and this release was not affected by the presence of saturation concentrations of D. Comparison to furnace anneals and the calculated time evolution of the temperature profiles suggests a simple model for the D release based on diffusion-limited release in the case of pulsed e-beam treatments and trap-limited release in the case of furnace bulk heating. These processes are closely related to hydrogen recycle in tokamaks and have implications for T inventory control and He ash removal.

  9. Characterization of HAZ of API X70 Microalloyed Steel Welded by Cold-Wire Tandem Submerged Arc Welding

    NASA Astrophysics Data System (ADS)

    Mohammadijoo, Mohsen; Kenny, Stephen; Collins, Laurie; Henein, Hani; Ivey, Douglas G.

    2017-03-01

    High-strength low-carbon microalloyed steels may be adversely affected by the high-heat input and thermal cycle that they experience during tandem submerged arc welding. The heat-affected zone (HAZ), particularly the coarse-grained heat-affected zone (CGHAZ), i.e., the region adjacent to the fusion line, has been known to show lower fracture toughness compared with the rest of the steel. The deterioration in toughness of the CGHAZ is attributed to the formation of martensite-austenite (M-A) constituents, local brittle zones, and large prior austenite grains (PAG). In the present work, the influence of the addition of a cold wire at various wire feed rates in cold-wire tandem submerged arc welding, a recently developed welding process for pipeline manufacturing, on the microstructure and mechanical properties of the HAZ of a microalloyed steel has been studied. The cold wire moderates the heat input of welding by consuming the heat of the trail electrode. Macrostructural analysis showed a decrease in the CGHAZ size by addition of a cold wire. Microstructural evaluation, using both tint etching optical microscopy and scanning electron microscopy, indicated the formation of finer PAGs and less fraction of M-A constituents with refined morphology within the CGHAZ when the cold wire was fed at 25.4 cm/min. This resulted in an improvement in the HAZ impact fracture toughness. These improvements are attributed to lower actual heat introduced to the weldment and lower peak temperature in the CGHAZ by cold-wire addition. However, a faster feed rate of the cold wire at 76.2 cm/min adversely affected the toughness due to the formation of slender M-A constituents caused by the relatively faster cooling rate in the CGHAZ.

  10. Characterization of HAZ of API X70 Microalloyed Steel Welded by Cold-Wire Tandem Submerged Arc Welding

    NASA Astrophysics Data System (ADS)

    Mohammadijoo, Mohsen; Kenny, Stephen; Collins, Laurie; Henein, Hani; Ivey, Douglas G.

    2017-05-01

    High-strength low-carbon microalloyed steels may be adversely affected by the high-heat input and thermal cycle that they experience during tandem submerged arc welding. The heat-affected zone (HAZ), particularly the coarse-grained heat-affected zone (CGHAZ), i.e., the region adjacent to the fusion line, has been known to show lower fracture toughness compared with the rest of the steel. The deterioration in toughness of the CGHAZ is attributed to the formation of martensite-austenite (M-A) constituents, local brittle zones, and large prior austenite grains (PAG). In the present work, the influence of the addition of a cold wire at various wire feed rates in cold-wire tandem submerged arc welding, a recently developed welding process for pipeline manufacturing, on the microstructure and mechanical properties of the HAZ of a microalloyed steel has been studied. The cold wire moderates the heat input of welding by consuming the heat of the trail electrode. Macrostructural analysis showed a decrease in the CGHAZ size by addition of a cold wire. Microstructural evaluation, using both tint etching optical microscopy and scanning electron microscopy, indicated the formation of finer PAGs and less fraction of M-A constituents with refined morphology within the CGHAZ when the cold wire was fed at 25.4 cm/min. This resulted in an improvement in the HAZ impact fracture toughness. These improvements are attributed to lower actual heat introduced to the weldment and lower peak temperature in the CGHAZ by cold-wire addition. However, a faster feed rate of the cold wire at 76.2 cm/min adversely affected the toughness due to the formation of slender M-A constituents caused by the relatively faster cooling rate in the CGHAZ.

  11. Deposition of duplex Al 2O 3/aluminum coatings on steel using a combined technique of arc spraying and plasma electrolytic oxidation

    NASA Astrophysics Data System (ADS)

    Gu, Weichao; Shen, Dejiu; Wang, Yulin; Chen, Guangliang; Feng, Wenran; Zhang, Guling; Fan, Songhua; Liu, Chizi; Yang, Size

    2006-02-01

    Plasma electrolytic oxidation (PEO) is a cost-effective technique that can be used to prepare ceramic coatings on metals such as Ti, Al, Mg, Nb, etc., and their alloys, but this promising technique cannot be used to modify the surface properties of steels, which are the most widely used materials in engineering. In order to prepare metallurgically bonded ceramic coatings on steels, a combined technique of arc spraying and plasma electrolytic oxidation (PEO) was adopted. In this work, metallurgically bonded ceramic coatings on steels were obtained using this method. We firstly prepared aluminum coatings on steels by arc spraying, and then obtained the metallurgically bonded ceramic coatings on aluminum coatings by PEO. The characteristics of duplex coatings were analyzed by X-ray diffractometer (XRD) and scanning electron microscopy (SEM). The corrosion and wear resistance of the ceramic coatings were also studied. The results show that, duplex Al 2O 3/aluminum coatings have been deposited on steel substrate after the combined treatment. The ceramic coatings are mainly composed of α-Al 2O 3, γ-Al 2O 3, θ-Al 2O 3 and some amorphous phase. The duplex coatings show favorable corrosion and wear resistance properties. The investigations indicate that the combination of arc spraying and plasma electrolytic oxidation proves a promising technique for surface modification of steels for protective purposes.

  12. ARc Welding (Industrial Processing Series).

    DTIC Science & Technology

    ARC WELDING , *BIBLIOGRAPHIES), (*ARC WELDS, BIBLIOGRAPHIES), ALUMINUM ALLOYS, TITANIUM ALLOYS, CHROMIUM ALLOYS, METAL PLATES, SPOT WELDING , STEEL...INERT GAS WELDING , MARAGING STEELS, MICROSTRUCTURE, HEAT RESISTANT ALLOYS, HEAT RESISTANT METALS, WELDABILITY, MECHANICAL PROPERTIES, MOLYBDENUM ALLOYS, NICKEL ALLOYS, RESISTANCE WELDING

  13. 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

  14. Effect of welding conditions on microstructure and properties of type 316L stainless steel submerged arc cladding

    SciTech Connect

    Murugan, N.; Parmar, R.S.

    1997-05-01

    Mathematical models were developed using response surface methodology for studying the direct and interaction effects of submerged arc welding parameters on stainless steel cladding geometry. The process parameters obtained from those models were employed to clad IS:2062 structural steel plate of 20-mm thickness using 316L stainless steel wire of 3.15-mm diameter. A low dilution of 22.57% was achieved in the cladding. Dilution was low when both voltage and welding speed were either high or low. Requirements of carbon and ferrite contents in the cladding were met by achieving low dilution in a single layer as well as multilayer cladding. The hardness of the existing martensitic structures at the intermediate mixed zones in overlays was below 400 VHN, which was attributed to the lower carbon content in the cladding. The solidification modes were found to be austenitic, ferritic, and austenitic and ferritic. The microstructure was found to be mainly cellular or cellular dendritic. The measured ferrite contents of cladding were well within their corresponding predicted values. The cladding possessed good ductility and resistance to intergranular corrosion.

  15. 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.

  16. Charpy toughness and tensile properties of a neutron irradiated stainless steel submerged-arc weld cladding overlay

    SciTech Connect

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-01-01

    The possibility of stainless steel cladding increasing the resistance of an operating nuclear reactor pressure vessel to extension of surface flaws is highly dependent upon the irradiated properties of the cladding. Therefore, weld overlay cladding irradiated at temperatures and fluences relevant to power reactor operation was examined. The cladding was applied to a pressure vessel steel plate by the submerged-arc, single-wire, oscillating electrode method. Three layers of cladding were applied to provide a cladding thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. There was considerable dilution of the type 309 in the first layer of cladding as a result of excessive melting of the base plate. Specimens for the irradiation study were taken from near the base plate/cladding interface and also from the upper layers of cladding. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to neutron fluences of 2 x 10/sup 23/ n/m/sup 2/ (E > 1 MeV). When irradiated, both types 308 and 309 cladding showed a 5 to 40% increase in yield strength accompanied by a slight increase in ductility in the temperature range from 25 to 288/sup 0/C. All cladding exhibited ductile-to-brittle transition behavior during impact testing.

  17. 21. Photocopy of ca. 1951 view (when furnaces were still ...

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

    21. Photocopy of ca. 1951 view (when furnaces were still in blast) looking north at central furnace complex with railroad cars of furnace charging materials in foreground and No. 2 Furnace at left. Photo marked on back 'David W. Corson from A. Devaney, N.Y.' - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  18. Toughness of 12%Cr ferritic/martensitic steel welds produced by non-arc welding processes

    SciTech Connect

    Ginn, B.J.; Gooch, T.G.

    1998-08-01

    Low carbon 12%Cr steels can offer reduced life cycle costs in many applications. The present work examined the behavior of commercial steels of varying composition when subject to low heat input welding by the electron beam (EB) process and to a forge cycle by linear friction welding (LFW). Charpy impact testing was carried out on the high temperature heat-affected zone (HAZ)/fusion boundary or weld interface, with metallographic examination. With EB welding, the ductile-brittle transition temperature (DBTT) was below 0 C (32 F) only for steel of low ferrite factor giving a fully martensitic weld area. Higher ferrite factor alloys showed predominantly ferritic transformed microstructures and a transition well above room temperature. Grain coarsening was found even with low EB process power, the peak grain size increasing with both heat input and steel ferrite factor. Use of LFW gave a fine weld area structure and DBTTs around 0 C even in high ferrite factor (FF) material.

  19. Submerged Arc Welding Consumables for HSLA (High Strength Low Alloy)-100 Steel

    DTIC Science & Technology

    1989-06-01

    0.001 Manganese 0.02 Silicon 0.01 Phosphorus 0.002 Sulfur 0.001 Nickel 0.05 Molybdenum 0.01 Chromium 0.02 Vanadium 0.001 Aluminum 0.002 Titanium 0.002...carbon-manganese steels with small amounts of alloys added such as aluminum, titanium , niobium , or vanadium . Since these steels exhibit high strength...83 Chemical check analysis for boron and phosphorus ................................................. 88 Mechanical property data summary

  20. 75 FR 81221 - Stainless Steel Sheet and Strip in Coils From Mexico; Preliminary Results of the Five-Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... by means of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent... trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from... of heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway...

  1. 75 FR 47780 - Stainless Steel Sheet and Strip in Coils From Mexico; Preliminary Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    ... is manufactured by means of vacuum arc remelting, with inclusion controls for sulphide of no more...\\ ``Arnokrome III'' is a trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel... commonly used in the production of heating ribbons for circuit breakers and industrial furnaces, and in...

  2. 75 FR 62104 - Certain Stainless Steel Sheet and Strip in Coils From Germany, Japan, the Republic of Korea, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ....020 percent or less. The product is manufactured by means of vacuum arc remelting, with inclusion.... Certain electrical resistance alloy steel is also excluded from the scope of the orders. This product is... breakers and industrial furnaces, and in rheostats for railway locomotives. The product is currently...

  3. 75 FR 6631 - Stainless Steel Sheet and Strip in Coils from Japan: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-10

    ... of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent and for... trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from... of heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway...

  4. 76 FR 2332 - Stainless Steel Sheet and Strip in Coils From Mexico; Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-13

    ... by means of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent... Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from the scope of... heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway locomotives...

  5. 75 FR 81214 - Stainless Steel Sheet and Strip in Coils From Italy: Preliminary Results of the Full Second Five...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... is manufactured by means of vacuum arc remelting, with inclusion controls for sulphide of no more...\\ ``Arnokrome III'' is a trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel... used in the production of heating ribbons for circuit breakers and industrial furnaces, and in...

  6. 75 FR 6627 - Stainless Steel Sheet and Strip in Coils From Mexico; Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-10

    ... by means of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent... of the Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from... of heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway...

  7. 75 FR 76700 - Stainless Steel Sheet and Strip in Coils From Taiwan: Final Results of Antidumping Duty...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-09

    ....020 percent or less. The product is manufactured by means of vacuum arc remelting, with inclusion... electrical resistance alloy steel is also excluded from the scope of the order. This product is defined as a... industrial furnaces, and in rheostats for railway locomotives. The product is currently available under...

  8. 75 FR 62101 - Stainless Steel Sheet and Strip in Coils From the Republic of Korea: Final Results of Expedited...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... by means of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent... trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from... of heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway...

  9. 76 FR 49450 - Stainless Steel Sheet and Strip in Coils From Germany, Italy, and Mexico: Revocation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ....020 percent or less. The product is manufactured by means of vacuum arc remelting, with inclusion.... Certain electrical resistance alloy steel is also excluded from the scope of the orders. This product is... industrial furnaces, and in rheostats for railway locomotives. The product is currently available under...

  10. 75 FR 5947 - Stainless Steel Sheet and Strip in Coils from Taiwan: Final Results and Rescission in Part of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-05

    ... of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent and for... of the Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from... heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway locomotives...

  11. 75 FR 49467 - Stainless Steel Sheet and Strip in Coils From Taiwan: Preliminary Results and Rescission in Part...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    .... The product is manufactured by means of vacuum arc remelting, with inclusion controls for sulphide of...\\ Arnokrome III is a trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel is... of heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway...

  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. 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.

  14. Correlation of flux composition and inclusion characteristics with submerged arc weld metal properties in HY-100 steel

    NASA Astrophysics Data System (ADS)

    Kettell, Kent W.

    1993-09-01

    Submerged arc weldments of HY-100 steel prepared under standard conditions with five commercially available fluxes were analyzed to discern a basis for the variation in mechanical properties associated with different flux use. The variations in flux chemistry resulted in alloyed weldments with diverse weld metal mechanical properties as evident by Charpy impact, tensile, dynamic tear, and microhardness tests. The microstructures and macrostructures were examined using optical and electron microscopy in order to determine the basis for the variations in strength and toughness. Scanning electron microscope and energy dispersive x-ray experiments were performed to determine the size, type, distribution and volume fraction of the non-metallic inclusions in the weld metal. Inclusion characterization revealed that the role of the flux in alloying had a more significant effect on the strength and toughness than did the presence of specific inclusions.

  15. 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.

  16. INTERIOR VIEW LOOKING NORTHEAST, SHOWING FURNACE NO. 1 (ca. 1910. ...

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

    INTERIOR VIEW LOOKING NORTHEAST, SHOWING FURNACE NO. 1 (ca. 1910. Nameplate reads: "Heroult Electric Furnace, Capacity 6 tons, Built by American Bridge Company, Pencoyd, PA, No. 33") - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  17. 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

  18. 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

  19. 58. LOOKING EAST DOROTHY SIX BLAST FURNACE WITH BRICK SHED ...

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

    58. LOOKING EAST DOROTHY SIX BLAST FURNACE WITH BRICK SHED No. 3 IN FOREGROUND ON RIGHT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  20. 31. VIEW OF TRIPPER CAR ON TOP OF BLAST FURNACE ...

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

    31. VIEW OF TRIPPER CAR ON TOP OF BLAST FURNACE STOCKING TRESTLE LOOKING EAST. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  1. 55. GENERAL NORTHEASTERN VIEW OF DOROTHY SIX BLAST FURNACE COMPLEX ...

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

    55. GENERAL NORTHEASTERN VIEW OF DOROTHY SIX BLAST FURNACE COMPLEX WITH LADLE HOUSE AND IRON DESULPHERIZATION BUILDING ON RIGHT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  2. INTERIOR VIEW OF BLAST FURNACE NO. 3 LOOKING EAST, SLAG ...

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

    INTERIOR VIEW OF BLAST FURNACE NO. 3 LOOKING EAST, SLAG RUNNERS & GATES IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

  3. VIEW LOOKING NORTHWEST WITH OPENHEARTH TO LEFT WITH BLAST FURNACE ...

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

    VIEW LOOKING NORTHWEST WITH OPEN-HEARTH TO LEFT WITH BLAST FURNACE NO. 2 AND CAST HOUSE TO THE RIGHT. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

  4. 70. CONTROL PANEL INSIDE OF THE DOROTHY SIX BLAST FURNACE ...

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

    70. CONTROL PANEL INSIDE OF THE DOROTHY SIX BLAST FURNACE STOCKHOUSE LOOKING NORTH. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  5. INTERIOR VIEW LOOKING EAST, BLAST FURNACE NO. 1 CLOSEUP, IRON ...

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

    INTERIOR VIEW LOOKING EAST, BLAST FURNACE NO. 1 CLOSE-UP, IRON NOTCH IN CENTER. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

  6. 59. REMAINS OF THE DOROTHY SIX BLAST FURNACE COMPLEX LOOKING ...

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

    59. REMAINS OF THE DOROTHY SIX BLAST FURNACE COMPLEX LOOKING NORTHEAST. THE LADLE HOUSE IS ON THE RIGHT. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  7. 50. IRON RUNNERS FOR CARRIE FURNACE No. 6 THE TUBES ...

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

    50. IRON RUNNERS FOR CARRIE FURNACE No. 6 THE TUBES IN THE FOREGROUND ARE PART OF THE TUYERE ASSEMBLY. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  8. 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

  9. 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

  10. 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

  11. 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

  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. 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

  14. 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

  15. 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

  16. GENERAL VIEW OF TURBOBLOWER BUILDING (LEFT), BLAST FURNACE (CENTER), AND ...

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

    GENERAL VIEW OF TURBO-BLOWER BUILDING (LEFT), BLAST FURNACE (CENTER), AND HOT BLAST STOVES (RIGHT). - Republic Iron & Steel Company, Youngstown Works, Haselton Blast Furnaces, West of Center Street Viaduct, along Mahoning River, Youngstown, Mahoning County, OH

  17. 1. LOOKING EAST AT BLAST FURNACES NO. 3 AND No. ...

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

    1. LOOKING EAST AT BLAST FURNACES NO. 3 AND No. 4 FROM CRAWFORD STREET IN THE CITY OF DUQUESNE. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  18. 13. SOUTHWEST VIEW OF CAST HOUSE No. 1, BLAST FURNACE ...

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

    13. SOUTHWEST VIEW OF CAST HOUSE No. 1, BLAST FURNACE No. 1, AND HOIST HOUSE No. 1. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  19. 35. CARRIE FURNACE No. 6 AND CAST HOUSE. THE CARRIE ...

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

    35. CARRIE FURNACE No. 6 AND CAST HOUSE. THE CARRIE BOILER SHOP IS ON THE RIGHT, IN FRONT OF HOT BLAST STOVES. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  20. Looking east at blast furnace no. 5 between the hot ...

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

    Looking east at blast furnace no. 5 between the hot blast stoves (left) and the dustcatcher (right). - U.S. Steel Edgar Thomson Works, Blast Furnace Plant, Along Monongahela River, Braddock, Allegheny County, PA

  1. 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

  2. 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

  3. Gas carburizing of steel with furnace atmospheres formed In Situ from propane and air: Part II. Analysis of the characteristics of gas flow in a batch-type sealed quench furnace

    NASA Astrophysics Data System (ADS)

    Stickels, C. A.; Mack, C. M.

    1980-09-01

    Gas flow dynamics in a batch-type sealed quench carburizing furnace were studied for operations utilizing low inlet gas flow rates. By analyzing the rate of change of furnace atmosphere composition when a sudden change is made in the inlet gas composition, it is shown that a significant amount of gas circulation occurs between the hot furnace chamber and the unheated vestibule. This circulation has the effect of increasing the mean residence time of gases within the furnace. A long mean residence time is advantageous for carburizing when the inlet gases consist of an airJhydrocarbon blend rather than prereacted endothermic gas.

  4. Narrow groove gas tungsten arc welding of ASTM A508 Class 4 steel for improved toughness properties

    SciTech Connect

    Penik, M.A. Jr.

    1997-04-01

    Welding of heavy section steel has traditionally used the automatic submerged arc welding (ASAW) process because of the high deposition rates achievable. However, the properties, particularly fracture toughness, of the weld are often inferior when compared to base material. This project evaluated the use of narrow groove gas tungsten arc welding (GTAW) to improve weld material properties. The welding procedures were developed for ASTM A508 Class 4 base material using a 1% Ni filler material complying to AWS Specification A.23-90-EF3-F3-N. A narrow groove joint preparation was used in conjunction with the GTAW process so competitive fabrication rates could be achieved when compared to the ASAW process. Weld procedures were developed to refine weld substructure to achieve better mechanical properties. Two heaters of weld wire were used to examine the effects of minor filler metal chemistry differences on weld mechanical properties. Extensive metallographic evaluations showed excellent weld quality with a refined microstructure. Chemical analysis of the weld metal showed minimal weld dilution by the base metal. Mechanical testing included bend and tensile tests to ensure weld quality and strength. A Charpy impact energy curve versus temperature and fracture toughness curve versus temperature were developed for each weld wire heat. Results of fracture toughness and Charpy impact testing indicated an improved transition temperature closer to that of the base material properties.

  5. Fatigue crack growth behavior of pressure vessel steels and submerged arc weldments in a high-temperature pressurized water environment

    SciTech Connect

    Liaw, P.K.; Logsdon, W.A.; Begley, J.A. . Research and Development Center)

    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. The 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.

  6. 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.

  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. Multi-Objective Process Optimization of Pulsed Plasma Arc Welding SS400 Steel Pipe with Foamed Aluminum Liner

    NASA Astrophysics Data System (ADS)

    Shih, Jing-Shiang; Tzeng, Yih-Fong; Lin, Young-Fu; Yang, Jin-Bin

    Principal component analysis (PCA) coupled with Taguchi methods are employed in the study for developing multiple quality characteristics optimization of pulsed plasma arc welding SS400 steel pipe with foamed aluminum liner (SPFAL). The quality characteristics investigated are the micro-hardness, the compression strength, and the bending strength of the weldments. Eight control factors selected are the tip aperture (Factor A), plasma base current (Factor B), plasma pulse current (Factor C), duty cycle (Factor D), pulse frequency (Factor E), shielding gas (Factor F), plasma gas (Factor G), and welding velocity (Factor H), respectively. It is shown by the experimental results that the optimal parameter combination of the pulsed plasma arc welding process is A1 (tip aperture: Ø1.5mm), B3 (plasma base current: 30A), C3 (plasma pulse current: 100A), D2 (duty cycle: 50%), E3 (pulse frequency: 300Hz), F2 (shielding gas: 14L/min), G3 (plasma gas: 0.4L/min), and H2 (welding velocity: 4RPM). Moreover, it is ascertained from the analysis of variance (ANOVA) results that plasma base current (B), plasma pulse current (C), duty cycle (D), and welding velocity (H) are the most important control factors in the process design, and thus strict control must be applied to them. They account for 75.02% of the total variance. The experimental results likewise show that the best process design could indeed enhance the multiple quality characteristics of the pulsed plasma arc welded SPFAL as 3020kgf of the bending strength, 13650kgf of the compression strength, and 180.4Hv of the hardness, respectively.

  9. Studies on the corrosion resistance of reinforced steel in concrete with ground granulated blast-furnace slag--An overview.

    PubMed

    Song, Ha-Won; Saraswathy, Velu

    2006-11-16

    The partial replacement of clinker, the main constituent of ordinary Portland cement by pozzolanic or latent hydraulic industrial by-products such as ground granulated blast furnace slag (GGBFS), effectively lowers the cost of cement by saving energy in the production process. It also reduces CO2 emissions from the cement plant and offers a low priced solution to the environmental problem of depositing industrial wastes. The utilization of GGBFS as partial replacement of Portland cement takes advantage of economic, technical and environmental benefits of this material. Recently offshore, coastal and marine concrete structures were constructed using GGBFS concrete because high volume of GGBFS can contribute to the reduction of chloride ingress. In this paper, the influence of using GGBFS in reinforced concrete structures from the durability aspects such as chloride ingress and corrosion resistance, long term durability, microstructure and porosity of GGBFS concrete has been reviewed and discussed.

  10. 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.

  11. High temperature furnace modeling and performance verifications

    NASA Technical Reports Server (NTRS)

    Smith, James E., Jr.

    1988-01-01

    Analytical, numerical and experimental studies were performed on two classes of high temperature materials processing furnaces. The research concentrates on a commercially available high temperature furnace using zirconia as the heating element and an arc furnace based on a ST International tube welder. The zirconia furnace was delivered and work is progressing on schedule. The work on the arc furnace was initially stalled due to the unavailability of the NASA prototype, which is actively being tested aboard the KC-135 experimental aircraft. A proposal was written and funded to purchase an additional arc welder to alleviate this problem. The ST International weld head and power supply were received and testing will begin in early November. The first 6 months of the grant are covered.

  12. Environmental cracking behavior of submerged arc-welded supermartensitic stainless steel weldments

    NASA Astrophysics Data System (ADS)

    Srinivasan, P. Bala; Sharkawy, S. W.; Dietzel, W.

    2004-04-01

    Supermartensitic stainless steel welds produced by submerged are welding were assessed for their microstructure and properties. Slow strain rate tests conducted on these specimens revealed that both the parent material and the weld metals are susceptible to cracking under conditions of hydrogen (H) charging.

  13. Direct measurement of solids: High temperature sensing: Phase 2, Experimental development and testing on furnace-heated steel blocks

    SciTech Connect

    Lemon, D.K.; Daly, D.S.

    1985-12-01

    Using average velocity measurements to estimate average profile temperature shows promise and merits further investigation. The current generation of electromagnetic acoustic transducers (EMATs) can transmit and detect signals in steel below the magnetic transition temperature. Techniques for calibrating ultrasonic velocity to internal temperature need further development. EMATs are inadequate ultrasonic transmitters for these applications. A high-energy, pulsed laser capable of generating more intense ultrasonic signals should be investigated as a transmitter. Recommendations are given for further work.

  14. 1. GENERAL VIEW OF BLAST FURNACE PLANT, KNOWN AS THE ...

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

    1. GENERAL VIEW OF BLAST FURNACE PLANT, KNOWN AS THE CARRIE FURNACES, FROM THE TOP OF WATER TOWER. CARRIE FURNACES No. 6 AND No. 7 ARE ON THE LEFT, AND FURNACES No. 3 AND No. 4 ARE ON THE RIGHT. THE TOWN OF RANKIN IS IN THE BACKGROUND. Jet Lowe, Photographer, 1989. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  15. 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.

  16. 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.

  17. 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.

  18. Blast furnace stove control

    SciTech Connect

    Muske, K.R.; Hansen, G.A.; Howse, J.W.; Cagliostro, D.J.; Chaubal, P.C.

    1998-12-31

    This paper outlines the process model and model-based control techniques implemented on the hot blast stoves for the No. 7 Blast Furnace at the Inland Steel facility in East Chicago, Indiana. A detailed heat transfer model of the stoves is developed. It is then used as part of a predictive control scheme to determine the minimum amount of fuel necessary to achieve the blast air requirements. The controller also considers maximum and minimum temperature constraints within the stove.

  19. Use of Al-Killed Ladle Furnace Slag in Si-Killed Steel Process to Reduce Lime Consumption, Improve Slag Fluidity

    NASA Astrophysics Data System (ADS)

    Behera, Narottam; Raddadi, Ahmad; Ahmad, Shahreer; Tewari, Neeraj; Zeghaibi, Othman

    Slag is a by-product formed in most metallurgical process. During the steelmaking process a large amount of slag is produced, which becomes a source of waste, which in many instances is land filled. Such areas filled with waste materials have become a significant source of pollution. Slag recycling is then becoming important in recent years. Recycling can be an efficient option to reduce such waste. Fluorspar (Calcium Fluoride) is generally used to help fluidize the slag; however, Fluorspar has a corrosive effect on the ladle refractory and is environmentally harmful. Alternatively, Calcium Aluminate synthetic slag is very effective in making the slag more fluid, but it is costly. The slag generated in Al-killed treatment at ladle can provide a material with advantages over Calcium aluminate synthetic slags and Fluorspar, by being low-cost, noncorrosive, and less environmentally harmful. Plant trials conducted at Hadeed indicate that Al-killed ladle slags coming from its Flat Product Ladle Furnace process could be used in place of Calcium Fluoride/ Bauxite/Calcium Aluminate fluxes for the production of Si- killed steel grades, thus reducing Lime consumption, reducing waste and improving desulphurization levels.

  20. Quantitative analysis of a complex metal carbide formed during furnace cooling of cast duplex stainless steel using EELS and EDS in the TEM.

    PubMed

    Kuimalee, Surasak; Chairuangsri, Torranin; Pearce, John T H; Edmonds, David V; Brown, Andrew P; Brydson, Rik M D

    2010-07-01

    In this work, a method to determine the atomic ratio of Mo and C within complex metal carbides using EELS in the TEM has been developed. The method is based on the determination of k-factors for given experimental conditions from the EEL spectra of Mo(2)C and MoO(3) standards, which had been independently checked by XRD and EPMA. Factors affecting the k(Mo/C) value of the Mo(2)C standard were also investigated and the value was shown to be insensitive to background subtraction window width but sensitive to prolonged irradiation and specimen thicknesses above a critical value. The method and k-factor obtained from the Mo(2)C standard was applied to spectra from a complex metal carbide precipitate formed during furnace cooling of a cast duplex stainless steel. Using EELS and EDS in the TEM, the composition was estimated to be (Cr(1.52)Fe(2.33)Mo(1.25)Ni(0.17)Si(0.46))C, which is close to M(6)C stoichiometry, and the structure was confirmed by electron diffraction. Copyright 2010 Elsevier Ltd. All rights reserved.

  1. 76 FR 25668 - Stainless Steel Sheet and Strip in Coils From Mexico: Final Results of the Five-Year (“Sunset...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ..., and sulfur of 0.020 percent or less. The product is manufactured by means of vacuum arc remelting... Company. Certain electrical resistance alloy steel is also excluded from the scope of the order. This... circuit breakers and industrial furnaces, and in rheostats for railway locomotives. The product is...

  2. 76 FR 25670 - Stainless Steel Sheet and Strip in Coils From Italy: Final Results of the Full Five-Year (“Sunset...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-05

    ... of vacuum arc remelting, with inclusion controls for sulphide of no more than 0.04 percent and for... trademark of the Arnold Engineering Company. Certain electrical resistance alloy steel is also excluded from... of heating ribbons for circuit breakers and industrial furnaces, and in rheostats for railway...

  3. Microstructural developments in neutron-irradiated mild steel submerged-arc weld metal

    NASA Astrophysics Data System (ADS)

    Buswell, J. T.; Bischler, P. J. E.; Fenton, S. T.; Ward, A. E.; Phythian, W. J.

    1993-10-01

    The microstructures of Magnox submerged-arc welds have been characterised to investigate the effects of surveillance and accelerated irradiation at temperatures in the range 190-290°C. The radiation hardening and embrittlement is influenced by the precipitation of Cu from solid solution. Mn has been found in the Cu-rich precipitates, together with an indication of P. The precipitates have structure coherent with the ferrite matrix and maintain a constant mean diameter during extended irradiation. Evidence has been obtained indicating that dislocation loops contribute to a matrix damage component in these welds.

  4. Method of Making Steel Strapping and Strip

    SciTech Connect

    1999-12-10

    Fact sheet written for the Inventions and Innovation Program about a new method for making steel strapping and strip from rod stock produced from scrap steel. There is a large movement in the American steel industry to utilize more recycled steel. Recycled steel melted in the electric arc furnaces of mini-mills is being used as the source of raw materials for an increasing number of products, largely due to its lower price. However, conventional processes for producing steel strapping and cold-rolled strip steel restrict manufacturers from using more than 50% recycled steel. In addition, steel strapping and cold-rolled strip steel traditionally require many production steps. They are produced from primary steel that has been cast into slab, heated, rolled to achieve the desired thickness, and slit to the desired width. The slitting process produces microcracks along the edge of the strapping or strip, which reduce tensile strength. A new continuous process produces steel strapping and 1/2 inch to 6 inch strip steel from the rod and strip stock made from scrap steel in mini-mills. The new process creates steel strapping and strip with improved strength and quality due to the absence of microcracks caused by the conventional slitting process. The finished product is cheaper because of the lower cost associated with using rod ad lower conversion costs. In addition, the higher tensile strength of the product allows for thinner strapping. The process represents a new approach to producing any steel strapping used for bundling and packaging items for storage or transport. In addition, this innovative new process can be used to produce cold-rolled strip steel, a basic raw material for automobile parts, hardware, office equipment, and many other products.

  5. Investigation of micro-structure and micro-hardness properties of 304L stainless steel treated in a hot cathode arc discharge plasma

    SciTech Connect

    Malik, Hitendra K.; Singh, Omveer; Dahiya, Raj P.

    2015-08-28

    We have established a hot cathode arc discharge plasma system, where different stainless steel samples can be treated by monitoring the plasma parameters and nitriding parameters independently. In the present work, a mixture of 70% N{sub 2} and 30% H{sub 2} gases was fed into the plasma chamber and the treatment time and substrate temperature were optimized for treating 304L Stainless Steel samples. Various physical techniques such as x-ray diffraction, energy dispersive x-ray spectroscopy and micro-vickers hardness tester were employed to determine the structural, surface composition and surface hardness of the treated samples.

  6. Investigation of micro-structure and micro-hardness properties of 304L stainless steel treated in a hot cathode arc discharge plasma

    NASA Astrophysics Data System (ADS)

    Malik, Hitendra K.; Singh, Omveer; Dahiya, Raj P.

    2015-08-01

    We have established a hot cathode arc discharge plasma system, where different stainless steel samples can be treated by monitoring the plasma parameters and nitriding parameters independently. In the present work, a mixture of 70% N2 and 30% H2 gases was fed into the plasma chamber and the treatment time and substrate temperature were optimized for treating 304L Stainless Steel samples. Various physical techniques such as x-ray diffraction, energy dispersive x-ray spectroscopy and micro-vickers hardness tester were employed to determine the structural, surface composition and surface hardness of the treated samples.

  7. Raceway control with oxygen, steam and coal for stable blast furnace operation

    SciTech Connect

    Chatterjee, L.M.

    1996-12-31

    Tata Steel operates seven blast furnaces at its Jamshedpur works. Coal injection was introduced in the three larger furnaces starting in 1991, and coal tar injection was commissioned in the A blast furnace in June, 1996. Presently, a coal injection level of 130 kg/thm has been achieved at G blast furnace, which is the newest and the largest among all blast furnaces at Tata Steel. The paper discusses the operational features of the blast furnaces at Tata Steel, practical limits of fuel injection, the philosophy of the control of raceway conditions, and experience with fuel injection at Tata Steel.

  8. Weldability and toughness evaluation of pressure vessel quality steel using the shielded metal arc welding (SMAW) process

    NASA Astrophysics Data System (ADS)

    Datta, R.; Mukerjee, D.; Mishra, S.

    1998-12-01

    The present study was carried out to assess the weldability properties of ASTM A 537 Cl. 1 pressure-vessel quality steel using the shielded metal arc welding (SMAW) process. Implant and elastic restraint cracking (ERC) tests were conducted under different welding conditions to determine the cold cracking susceptibility of the steel. The static fatigue limit values determined for the implant test indicate adequate resistance to cold cracking even with unbaked electrodes. The ERC test, however, established the necessity to rebake the electrodes before use. Lamellar tearing tests carried out using full-thickness plates under three welding conditions showed no incidence of lamellar tearing upon visual examination, ultrasonic inspection, and four-section macroexamination. Lamellar tearing tests were repeated using machined plates, such that the central segregated band located at the midthickness of the plate corresponded to the heat-affected zone (HAZ) of the weld. Only in one (no rebake, heat input: 14.2 kj cm-1, weld restraint load: 42 kg mm-2) of the eight samples tested was lamellar tearing observed. This was probably accentuated due to the combined effects of the presence of localized pockets of a hard phase (bainite) and a high hydrogen level (unbaked electrodes) in the weld joint. Optimal welding conditions were formulated based on the above tests. The weld joint was subjected to extensive tests and found to exhibit excellent strength (tensile strength: 56.8 kg mm-2, or 557 MPa), and low temperature impact toughness (7.4 and 4.5 kg-m at-20 °C for weld metal, WM, and HAZ) properties. Crack tip opening displacement tests carried out for the WM and HAZ resulted in δm values 0.36 and 0.27 mm, respectively, which indicates adequate resistance to brittle fracture.

  9. Weldability and toughness evaluation of pressure vessel quality steel using the shielded metal arc welding (SMAW) process

    SciTech Connect

    Datta, R.; Mukerjee, D.; Mishra, S.

    1998-12-01

    The present study was carried out to assess the weldability properties of ASTM A537 Cl. 1 pressure-vessel quality steel using the shielded metal arc welding (SMAW) process. Implant and elastic restraint cracking (ERC) tests were conducted under different welding conditions to determine the cold cracking susceptibility of the steel. The static fatigue limit values determined for the implant test indicate adequate resistance to cold cracking even with unbaked electrodes. The ERC test, however, established the necessity to rebake the electrodes before use. Lamellar tearing tests carried out using full-thickness plates under three welding conditions showed no incidence of lamellar tearing upon visual examination, ultrasonic inspection, and four-section macroexamination. Lamellar tearing tests were repeated using machined plates, such that the central segregated band located at the midthickness of the plate corresponded to the heat-affected zone (HAZ) of the weld. Only in one (no rebake, heat input: 14.2 kJ cm{sup {minus}1}, weld restraint load: 42 kg mm{sup {minus}2}) of the eight samples tested was lamellar tearing observed. This was probably accentuated due to the combined effects of the presence of localized pockets of a hard phase (bainite) and a high hydrogen level (unbaked electrodes) in the weld joint. Optimal welding conditions were formulated based on the above tests. The weld joint was subjected to extensive tests and found to exhibit excellent strength (tensile strength:56.8 kg mm{sup {minus}2}, or 557 MPa), and low temperature impact toughness (7.4 and 4.5 kg-m at {minus}20 C for weld metal, WM, and HAZ) properties. Crack tip opening displacement tests carried out for the WM and HAZ resulted in {delta}{sub m} values 0.36 and 0.27 mm, respectively, which indicates adequate resistance to brittle fracture.

  10. Saldanha Steel project: The zero emission philosophy

    SciTech Connect

    Holmes, A.T.; Greenwalt, D.

    1997-12-31

    Saldanha Steel is a new, green-field, semi-integrated steelworks developed on the west coast near the southern tip of Africa. The harbor in Saldanha Bay was developed as an iron ore export facility for Sishen ore in the late seventies. The Sishen Iron Ore Mine is located some 800 km inland and is currently exporting about 17 million tons annually. Saldanha steel will now utilize some 2 million tons per annum of this ore, of which about 45% will be converted into liquid iron in a Corex direct reduction smelting process. Excess reducing gas (CO and H{sub 2}) from the Corex plant will then be used to convert the remaining 55% of the iron ore into solid sponge iron (DRI) via a Midrex plant. The liquid and solid iron will be further processed in a Conarc furnace, which is a hybrid between an oxygen converter and an electric arc furnace.

  11. Cupola Furnace Computer Process Model

    SciTech Connect

    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 alloy 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).

  12. 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.

  13. 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.

  14. Inclusion phases and the nucleation of acicular ferrite in submerged arc welds in high strength low alloy steels

    NASA Astrophysics Data System (ADS)

    Dowling, J. M.; Corbett, J. M.; Kerr, H. W.

    1986-09-01

    Series of submerged arc welds of HSLA steel made with three different fluxes and metallic additions of Ti, Mo, and Cr have been examined to study the inclusions and their role in the nucleation of acicular ferrite. Inclusion phases and compositions have been analyzed by electron diffraction and X-ray microanalysis. These analyses have shown that the inclusions contained many different compounds, the proportions of each depending upon both the flux and metallic additions. Six inclusion phases have been identified: galaxite (Al2O3 ṡ MnO), a titanium-rich compound (probably TiO), a copper sulfide, a manganese sulfide, a silica, and an aluminum-rich phase. No correlation was found between the amount of acicular ferrite in the weld metal and either average inclusion composition or individual inclusion phases. No epitaxial relationships between inclusions and adjacent ferrite grains could be identified. It has been concluded that inclusions nucleate acicular ferrite by acting as inert substrates according to the classical theory of heterogeneous nucleation. Because most inclusions are multi-phase and are touched by several ferrite grains, it has also been concluded that each inclusion can nucleate several ferrite grains, due to local regions of high surface energy on the inclusion.

  15. 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.

  16. Joining of dissimilar AZ31B magnesium alloy and SS400 mild steel by hybrid gas tungsten arc friction stir welding

    NASA Astrophysics Data System (ADS)

    Joo, SungMin

    2013-11-01

    The joining of dissimilar materials, magnesium alloy (AZ31B) and mild steel (SS400), was performed using a hybrid gas tungsten arc-friction stir welding (HGTAFSW) method that applied a preceding gas tungsten arc welding (GTAW) preheating heat source to a mild steel plate surface during friction stir welding (FSW). The mechanical and microstructural characteristics of the HGTAFS welds were evaluated and compared to those of FS welds to confirm the effect of the additional GTAW preheating heat source. The tensile strength of the HGTAFS welds was approximately 91% of that of the magnesium alloy base metal but higher than that of the FS welds. This was attributed to the enhanced material plastic flow and partial annealing effect in the magnesium alloy and mild steel materials by GTAW reheating of the mild steel side, which induced a significant increase in the elongation of the welds. The concentration profiles indicated that no intermetallic FeAl and FeAl3 compounds had formed according to the phase diagram, which led to a decrease in joint strength. Overall, the use of HGTAFSW by applying a GTAW preheating heat source to a mild steelplate surface resulted in a mechanically sounder and metallurgically defect-free welds compared to FSW.

  17. EXTERIOR VIEW, NO. 3 CAST HOUSE CENTER AND BLAST FURNACE ...

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

    EXTERIOR VIEW, NO. 3 CAST HOUSE CENTER AND BLAST FURNACE NO. 3 (JANE FURNACE)/ORE BRIDGE TO THE RIGHT, WITH SINTERING PLANT CONVEYORS & TRANSFER HOUSE IN FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

  18. VIEW LOOKING NORTH, VIEW OF BLAST FURNACE NO. 2 (LEFT) ...

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

    VIEW LOOKING NORTH, VIEW OF BLAST FURNACE NO. 2 (LEFT) SHARING THE SAME CAST HOUSE WITH BLAST FURNACE NO. 1. ORE BRIDGE & BLOWER HOUSE TO RIGHT, HULETT CAR DUMPER IS IN LEFT FOREGROUND. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

  19. 6. NO. 2 CONTINUOUS SLAB REHEATING FURNACE OF THE 160' ...

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

    6. NO. 2 CONTINUOUS SLAB REHEATING FURNACE OF THE 160' PLATE MILL. FURNACE SHOWING DURING DEMOLITION. C HOOK USED TO CHANGE ROLLS IS VISIBLE IN FRONT OF FURNACE. - U.S. Steel Homestead Works, 160" Plate Mill, Along Monongahela River, Homestead, Allegheny County, PA

  20. 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

  1. 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

  2. 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

  3. Rebuilding of Rautaruukki blast furnaces

    SciTech Connect

    Kallo, S.; Pisilae, E.; Ojala, K.

    1997-12-31

    Rautaruukki Oy Raahe Steel rebuilt its blast furnaces in 1995 (BF1) and 1996 (BF2) after 10 year campaigns and production of 9,747 THM/m{sup 3} (303 NTHM/ft{sup 3}) and 9,535 THM/m{sup 3} (297 NTHM/ft{sup 3}), respectively. At the end of the campaigns, damaged cooling system and shell cracks were increasingly disturbing the availability of furnaces. The goal for rebuilding was to improve the cooling systems and refractory quality in order to attain a 15 year campaign. The furnaces were slightly enlarged to meet the future production demand. The blast furnace control rooms and operations were centralized and the automation and instrumentation level was considerably improved in order to improve the operation efficiency and to reduce manpower requirements. Investments in direct slag granulation and improved casthouse dedusting improved environmental protection. The paper describes the rebuilding.

  4. Application of the Spectral Line-based Weighted-Sum-of-Gray-Gases model (SLWSGG) to the calculation of radiative heat transfer in steel reheating furnaces firing on low heating value gases

    NASA Astrophysics Data System (ADS)

    Nguyen, P. D.; Danda, A.; Embouazza, M.; Gazdallah, M.; Evrard, P.; Feldheim, V.

    2012-06-01

    The Spectral Line-based Weighted-Sum-of-Gray-Gases (SLWSGG) model is applied to calculate the gaseous radiative properties of the aero- or oxy-combustion products of low heating value gases issued from steel making process such as Blast Furnace Gas (BFG) as well as of high heating value gases such as Coke Oven Gas (COG) and conventional Natural Gas (NG). The comparison of total emissivities shows that the 3-gray-gases SLWSGG model is in very good agreement with the Hottel and Sarofim's database. The 3-gray-gases SLWSGG model is then integrated into AnsysFluent® Discrete Ordinates method under User Defined Function and CFD simulations are performed using these combined models. The simulations are done, with full combustion-radiation coupling, for steel reheating furnaces firing on three types of gases: BFG, COG and NG. The results are compared with the simulations realized with the 1-gray-gas WSGG model available in AnsysFluent®. The comparison shows that the 1-gray-gas WSGG model highly overestimates the steel discharging temperature as compared to the 3-gray-gases SLWSGG model. Significant temperature differences are observed between the two radiative models, i.e. 116°C, 55°C and 67°C for the BFG, COG and NG cases, respectively. It can be concluded that the 3-gray-gases SLWSGG model should be used to calculate the radiation heat transfer in large industrial furnaces with more accuracy not only for low heating value gases such as BFG but also for high heating value gases such as COG and NG.

  5. General view of blast furnace "A"; looking southeast; The building ...

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

    General view of blast furnace "A"; looking southeast; The building to the right is the crucible steel building - Bethlehem Steel Corporation, South Bethlehem Works, Blast Furnace "A", Along Lehigh River, North of Fourth Street, West of Minsi Trail Bridge, Bethlehem, Northampton County, PA

  6. 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

  7. Blast furnace repairs, relines and modernizations

    SciTech Connect

    Carpenter, J.A.; Swanson, D.E; Chango, R.F. . Burns Harbor Div.)

    1994-09-01

    Bethlehem Steel's Burns Harbor Div. operates two 89,000-cu ft blast furnaces, D and C, built in 1969 and 1972. These furnaces have been in the forefront of blast furnace performance since they were blown-in. To maintain a credible operation throughout the past 25 years their performance has been improved continuously. Production was increased approximately 3%/year while fuel rate decreased 1%/year. This presentation summarizes the early repairs, relines and improvements that have sustained and enhanced the furnace's performance. The fourth reline of both furnaces will be discussed in detail. As part of the 1991 reline of D furnace its lines were improved and modern penstocks installed. The bosh, tuyere jacket, hearth jacket and both cast floors were replaced. The furnace now has a larger hearth making it easier to control and, liquid level is no longer a problem when pulling the wind to shut down. The new cast floor with its increased trough length has much improved separation of slag from iron and lowered refractory consumption. Since the cast floors on D furnace were changed, there has been a reduction in accidents and absenteeism. This may be related to the change in work practices on the new cast floors. The 1994 reline of C furnace incorporates those improvements made on D furnace in 1991. In addition, C furnace will have high-density cooling which is expected to double its campaign from 6 to 12 years, without interim repairs.

  8. In-situ phase mapping and direct observations of phase transformations during arc welding of 1045 steel

    NASA Astrophysics Data System (ADS)

    Elmer, J. W.; Palmer, T. A.

    2006-07-01

    In-situ spatially resolved X-ray diffraction (SRXRD) experiments were performed during gas tung-sten arc (GTA) welding of AISI 1045 C-Mn steel. Ferrite (α) and austenite (γ) phases were identified and quantified in the weld heat-affected zone (HAZ) from the real time SRXRD data. The results were compiled with weld temperatures calculated using a coupled thermal fluids model to create a phase map of the HAZ. Kinetics of the α → γ transformation during weld heating and the reverse γ → α transformation during weld cooling were extracted from the map. Superheating as high as 250 °C above the A3 temperature was observed for the α → γ phase transformation to reach completion at locations near the fusion zone (FZ) boundary. The SRXRD experiments revealed that the newly created γ phase exists with two distinct lattice parameters, resulting from the inhomogeneous distribution of carbon and manganese in the starting pearlitic/ferritic microstructure. During cooling, the reverse γ → α phase transformation was shown to depend on the HAZ location. In the fine-grained region of the HAZ, the γ → α transformation begins near the A3 temperature and ends near the A1 temperature. In this region, where the cooling rates are below 40 °C/s, the transformation occurs by nucleation and growth of pearlite. In the coarse-grained region of the HAZ, the γ → α transformation requires 200 °C of undercooling for completion. This high degree of undercooling is caused by the large grains coupled with cooling rates in excess of 50 °C/s that result in a bainitic transformation mechanism.

  9. In-Situ Phase Mapping and Direct Observations of Phase Transformations During Arc Welding of 1045 Steel

    SciTech Connect

    Elmer, J; Palmer, T

    2005-09-13

    In-situ Spatially Resolved X-Ray Diffraction (SRXRD) experiments were performed during gas tungsten arc (GTA) welding of AISI 1045 C-Mn steel. Ferrite ({alpha}) and austenite ({gamma}) phases were identified and quantified in the weld heat-affected zone (HAZ) from the real time x-ray diffraction data. The results were compiled along with weld temperatures calculated using a coupled thermal fluids weld model to create a phase map of the HAZ. This map shows the {alpha} {yields} {gamma} transformation taking place during weld heating and the reverse {gamma} {yields} {alpha} transformation taking place during weld cooling. Superheating is required to complete the {alpha} {yields} {gamma} phase transformation, and the amount of superheat above the A3 temperature was shown to vary with distance from the centerline of the weld. Superheat values as high as 250 C above the A3 temperature were observed at heating rates of 80 C/s. The SRXRD experiments also revealed details about the {gamma} phase not observable by conventional techniques, showing that {gamma} is present with two distinct lattice parameters as a result of inhomogeneous distribution of carbon and manganese in the starting pearlitic/ferritic microstructure. During cooling, the reverse {gamma} {yields} {alpha} phase transformation was shown to depend on the HAZ location. In the fine grained region of the HAZ, at distances greater than 2 mm from the fusion line, the {gamma} {yields} {alpha} transformation begins near the A3 temperature and ends near the A1 temperature. In this region of the HAZ where the cooling rates are below 40 C/s, the transformation occurs by nucleation and growth of pearlite. For HAZ locations closer to the fusion line, undercoolings of 200 C or more below the A1 temperature are required to complete the {gamma} {yields} {alpha} transformation. In this region of the HAZ, grain growth coupled with cooling rates in excess of 50 C/s causes the transformation to occur by a bainitic mechanism.

  10. 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

  11. 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.

  12. The role of titanium in the non-metallic inclusions which nucleate acicular ferrite in the submerged arc weld (SAW) fusion zones of Navy HY-100 steel

    SciTech Connect

    Fox, A.G.; Brothers, D.G.

    1995-04-01

    The origin of acicular ferrite in the weld metal of submerged arc weldments on high strength steels is very complex and depends upon the chemical composition for the steel base plate and filler wire, the composition of the flux used during welding and the cooling rate of the weld metal during the transformation of the undercooled metastable austenite. The strength and toughness of weld metal improves as the amount of acicular ferrite increases due its fine basket weave microstructure and so it is important to understand the mechanism of its formation so that the volume fraction of acicular ferrite can be maximized in steel weld metal. The chemical composition of the filler wire mostly determines the final composition of the weld metal although the composition of the base plate is important because of dilution effects. In high strength steels the alloying elements such as carbon, nickel, chromium, copper nd niobium are present to achieve the required strength levels and a fortuitous outcome of this is a continuous cooling transformation (CCT) diagram with features that mean that bainite is the major transformation product during the arc welding of these steels provided a suitable weld power and preheat/interpass temperature is chosen during multi-run welding. Once a suitable weld-metal hardenability and cooling rate has been established the amount of acicular ferrite nucleated will depend on the size, number, distribution and chemical composition of the non-metallic inclusions. Suitable inclusions appear to be in the size range 0.2--2.0 micrometers with a mean size of 0.5 micrometers being about an optimum value. These inclusions usually contain manganese, silicon, aluminum and titanium as their major constituents and do not appear to be exactly spherical but have a faceted or slightly angular appearance.

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

    SciTech Connect

    Zhang, Qi; Hasanbeigi, Ali; Price, Lynn; Lu, Hongyou; Arens, Marlene

    2016-09-01

    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. 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.

  14. 49. Taken from highline; "McKinley hat" remains on "B" furnace; ...

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

    49. Taken from high-line; "McKinley hat" remains on "B" furnace; no longer used, "McKinley hat was open receptacle with bell below. Hat carried charge to furnace top, dumping it to bell; bell locked onto furnace top, dropping charge into furnace. Looking east - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  15. Distribution of radionuclides during melting of carbon steel

    SciTech Connect

    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 other 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.

  16. bdGas carburizing of steel with furnace atmospheres formed in situ from methane and air and from butane and air

    NASA Astrophysics Data System (ADS)

    Stickels, C. A.; Mack, C. M.; Pieprzak, J. A.

    1982-12-01

    Carburizing experiments were conducted at 927°C (1700°F) and 843°C (1550°F) using furnace atmospheres formed from methane and air and from butane and air introduced directly into the carburizing furnace. Gas flow rates were low to promote equilibration of the reaction products within the furnace. The air flow rate was held constant while the methane or butane flow was automatically regulated to maintain a constant oxygen potential, as measured by a zirconia oxygen sensor, within the furnace. In comparing the results of these experiments with earlier results obtained using propane and air, several differences were noted: (a) The methane content of the furnace atmosphere, measured by infrared analysis, was about twice as great when methane was the feed gas rather than propane or butane. This was true despite the fact that the mean residence time of the gas within the furnace was greater in the methane experiments. Methane appears to be less effective than propane or butane in reducing the CO2 and H2O contents to the levels required for carburizing. (b) There was a greater tendency for the CO content of the furnace atmosphere to decrease at high carbon potentials when methane is used instead of propane or butane. The decrease in CO content is due to hydrogen dilution caused by sooting in the furnace vestibule. These differences in behavior make propane or butane better suited than methane for in situ generation of carburizing atmospheres. However, there is no difference in the amount of carburizing occurring at a specified carbon potential when methane, propane, or butane are used as the feed gas in this process.

  17. Furnace assembly

    DOEpatents

    Panayotou, Nicholas F.; Green, Donald R.; Price, Larry S.

    1985-01-01

    A method of and apparatus for heating test specimens to desired elevated temperatures for irradiation by a high energy neutron source. A furnace assembly is provided for heating two separate groups of specimens to substantially different, elevated, isothermal temperatures in a high vacuum environment while positioning the two specimen groups symmetrically at equivalent neutron irradiating positions.

  18. Furnace assembly

    DOEpatents

    Panayotou, N.F.; Green, D.R.; Price, L.S.

    A method of and apparatus for heating test specimens to desired elevated temperatures for irradiation by a high energy neutron source. A furnace assembly is provided for heating two separate groups of specimens to substantially different, elevated, isothermal temperatures in a high vacuum environment while positioning the two specimen groups symmetrically at equivalent neutron irradiating positions.

  19. Nonmetallic inclusions in a chromium steel intended for the power engineering industry

    NASA Astrophysics Data System (ADS)

    Kolpishon, E. Yu.; Mal'Ginov, A. N.; Romashkin, A. N.; Durynin, V. A.; Afanas'ev, S. Yu.; Shitov, E. V.; Afanas'eva, L. T.; Batov, Yu. M.

    2010-06-01

    The behavior of oxygen in the course of manufacturing large steel ingots containing 1.5-20% Cr, the formation of oxides depending on the contents of deoxidizing agents and oxygen, and the composition of the oxide phase in ingots and forgings made of the steel are considered. The steel is manufactured using an arc steel-melting furnace and unit for complex treatment of steel (ASF-ACSPU technology) and the ASF-ACSPU technology and electroslag remelting (ESR). It is shown that the oxide phase composition depends on the contents of strong deoxidizing agents and oxygen and the development of secondary oxidation. Chromium- and manganese-containing spinels are characteristic species of the secondary and tertiary oxides in the chromium steel in the case of deficient aluminum and silicon.

  20. Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and trace metals in the blood of nonoccupationally exposed residents living in the vicinity of a municipal solid waste incinerator and electric arc furnace.

    PubMed

    Chen, Yan-Min; Lin, Yuan-Chung; Wu, Tzi-Yi; Chang-Chien, Guo-Ping; Ma, Wen-Feng

    2010-06-01

    This study examines levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and trace metals in the blood of the nonoccupationally exposed residents living in the vicinity of municipal solid waste incinerators (MSWIs) and electric arc furnaces (EAFs). The analysis found that older females had higher concentrations of PCDD/Fs and older males had higher body mass index (BMI) values and higher concentrations of PCDD/Fs. Moreover, sex appeared to affect the levels of PCDD/Fs because, overall, females showed higher levels of PCDD/Fs. The results of a principal component analysis indicated that the characteristics of the blood were more similar to the characteristics of the stack flux gas in MSWIs than those in EAFs. When sex, age, and BMI values were taken into consideration, none of the factors appeared to significantly affect PCDD/F and trace metal blood levels. However, when participants were divided into eight categories and analyzed, it was found that sex was the most important factor affecting levels of trace metals in blood and that males had higher concentrations of Pb, Al, Cd, and Cu.

  1. Influence of weld metal alloying additions to extend the heat input range for the submerged arc welding of high strength steels. Final report

    SciTech Connect

    Liu, S.; Olson, D.L.; Ramirez, J.E.

    1993-12-16

    Weld metal microstructural development for high strength steels when welded with submerged arc welding process was investigated as a function of consumable composition and thermal experience. Of specific interest is the effect of systematic variations of microalloying additions on broadening of applicable heat input range. Controlled weld metal oxygen content, particularly in the range of 300 to 400 ppm, has been found to improve HY-130 steel weld metal toughness. Molybdenum additions was found to increase the strength of the HY-130 steel weld deposits. Copper additions up to 3.5 wt.pct. were found to strengthen the high strength steel weld metals, in particular, those of higher heat input, 3.6 kJ/mm. Niobium additions alone did not provide as powerful strengthening effect in the high heat input weld metals as the copper additions. In the case of copper-enriched welds, multi-pass welding induced both the precipitation and overaging of epsilon copper precipitates in the reheated weld metal which resulted in non-uniform mechanical properties. When added together, copper and niobium produced the synergistic effect of dual precipitation (Epsilon copper and niobium carbides) which provided the needed strength and thermal stability to the reheated weld metal even at high heat inputs. With this novel approach, the applicable heat input range to produce both adequate weld metal strength and toughness in high strength steels (Sigma y > 690 MPa) can be extended significantly. The optimal additions for copper and niobium were found to be 3.3 and up to 0. 1 wt. pct., Heat input, High strength steel, Precipitation strengthening, Copper, Niobium, Single and multi-pass welding.

  2. EXTERIOR VIEW LOOKING WEST,BLAST FURNACE TO THE RIGHT, ORE YARD ...

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

    EXTERIOR VIEW LOOKING WEST,BLAST FURNACE TO THE RIGHT, ORE YARD TO THE CENTER, HEYL & PATTERSON CAR DUMPER TO THE LEFT. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 3, Donner Avenue, Monessen, Westmoreland County, PA

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

    SciTech Connect

    Ghomashchi, Reza 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. 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.

  4. Increasing blast furnace productivity. Is there a universal solution for all blast furnaces?

    SciTech Connect

    Chaubal, P.C.; Ranade, M.G.

    1997-12-31

    In the past few years there has been a major effort in the integrated plants in the US to increase blast furnace productivity. Record production levels have been reported by AK Steel using direct reduced/hot briquetted iron (DRI/HBI) and high levels of natural gas (NG)-oxygen injection at their Middletown blast furnace. Similarly, US Steel-Gary No. 13 reported high productivity levels with PCI and oxygen enrichment. A productivity of 6 NTHM/day/100 ft{sup 3}WV was the norm in the past, but today levels higher than 11 NTHM/day/100ft{sup 3}WV have been reached on a sustained basis. These high productivity levels have been an important aspect of facility rationalization efforts, as companies seek to maximize their throughput while reducing costs. Hot metal demand in a particular plant depends on downstream capabilities in converting hot metal to saleable steel. Single vs. multi-furnace plants may have different production requirements for each facility. Business cycles may influence productivity requirements from different furnaces of a multiple furnace plant, more so for those considered as swing furnaces. Therefore, the production requirement for individual blast furnaces is different for different plants. In an effort to understand productivity improvement methods, calculations were made for a typical 8 m hearth diameter furnace using data and experience gathered on Inland`s operation. Here the authors present the results obtained in the study.

  5. The optimization of the removal process of nitrogen content from steels treated in vacuum facilities

    NASA Astrophysics Data System (ADS)

    Magaon, Miruna; Vǎtǎşescu, Mihail; HepuÅ£, Teodor; Crişan, Eugen

    2017-07-01

    Purity in gases has a considerable influence on the quality of steel, more precisely nitrogen and hydrogen. In this paper are presented the results of researches conducted at an electrical steelwork, in order to establish correlations between a series of vacuuming parameters, which influence the amount of nitrogen removed from the liquid steel. The steelwork is equipped with CAE (Electric Arc Furnace) type EBT (Eccentric Bottom Tapping), LF (Ladle-Furnace) and VD (Vacuum-Degassing) facilities and a 5 wires MTC (Continuous Casting Machine). All the data obtained during the research was processed in the MATLAB calculation program, the results being presented both in analytical and graphical form. The technological analyze of the correlation equations and the graphical representations allowed to establish the variation limits of the independent parameters, in order to advancely reduce the steel hydrogen content.

  6. 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

  7. 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

  8. Structure-phase states and wear resistance of deposition surface formed on steel by electric arc method

    NASA Astrophysics Data System (ADS)

    Raikov, S. V.; Kapralov, E. V.; Vashchuk, E. S.; Budovskikh, E. A.; Gromov, V. E.; Ivanov, Yu F.; Sosnin, K. V.

    2015-01-01

    Investigations of elementary and phase structure, state of defect structure and tribological characteristics of deposition, formed on a low carbon low-alloy steel by a welding method were carried out. It was revealed that deposition, formed on a steel surface is accompanied by the multilayer formation, and increase of wear resistance of the layer deposition as determined.

  9. Deposition of Functional Coatings Based on Intermetallic Systems TiAl on the Steel Surface by Vacuum Arc Plasma

    NASA Astrophysics Data System (ADS)

    Budilov, V.; Vardanyan, E.; Ramazanov, K.

    2015-11-01

    Laws governing the formation of intermetallic phase by sequential deposition of nano-sized layers coatings from vacuum arc plasma were studied. Mathematical modeling process of deposition by vacuum arc plasma was performed. In order to identify the structural and phase composition of coatings and to explain their physical and chemical behaviour XRD studies were carried out. Production tests of the hardened punching tools were performed.

  10. TRP0033 - PCI Coal Combustion Behavior and Residual Coal Char Carryover in the Blast Furnace of 3 American Steel Companies during Pulverized Coal Injection (PCI) at High Rates

    SciTech Connect

    Veena Sahajwalla; Sushil Gupta

    2005-04-15

    Combustion behavior of pulverized coals (PC), gasification and thermal annealing of cokes were investigated under controlled environments. Physical and chemical properties of PCI, coke and carbon residues of blast furnace dust/sludge samples were characterized. The strong influence of carbon structure and minerals on PCI reactivity was demonstrated. A technique to characterize char carryover in off gas emissions was established.

  11. 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

  12. Emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from both of point and area sources of an electric-arc furnace-dust treatment plant and their impacts to the vicinity environments.

    PubMed

    Yu, Kuei-Min; Lee, Wen-Jhy; Tsai, Perng-Jy; Fang, Kenneth; Lin, Mark

    2010-08-01

    This study was set out to investigate emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from both the stack (i.e., point source) and plant fugitives (i.e., area source) of an electric-arc furnace-dust treatment plant (EAFDTP) and their impact to the vicinity environments. The emission rate of the point source (2,360 ng I-TEQh(-1)) was determined directly by measuring PCDD/F concentrations of the stack flue gas. The emission rate of the area source (1,080 ng I-TEQ m(-2)h(-1)) was estimated by using the Industrial Sources Complex Short-Term (ISCST3) model based on concentrations measured at the downwind side of the plant. The mean emission factors of 785 and 893 ng I-TEQ ton(-1) ZnO were found for the point and area source, respectively. The above results suggest that the area source accounted for more than 50% of total PCDD/F emissions for the selected EAFDTP. The contribution of the point source to the atmospheric PCDD/F concentrations of the upwind site and downwind site of the EAFDTP were 0 and 0.27 fg I-TEQ Nm(-3), respectively. The contributions of the area source were 0.020 and 3.3 fg I-TEQ Nm(-3), respectively. The total contribution of the selected EAFDTP (including both the point and area sources) to the concentrations in both upwind and downwind side vicinities were all less than 10%. Finally, the impact of PCDD/F emissions from the selected EAFDTP to the vicinity atmospheric environments was discussed in the present study.

  13. Rotary furnace supervisory control system at Timken`s Gambrinus furnace No. 3

    SciTech Connect

    Cates, L.E.; Schweinsberg, E.; Fearn, T.

    1995-07-01

    During 1994, the Timken Co. upgraded the rotary hearth billet furnace at the Gambrinus plant. As part of the upgrade, a new furnace supervisory control system was installed. This system includes an on-line thermal model which calculates steel temperatures and gradients while accounting for changing project dimensions and steel grades. Temperature and production rate set points are calculated to consistently produce properly heated pieces. The set point control strategy will reduce fuel consumption, decrease temperature variations between pieces, prevent overheating, and minimize the amount of scaling and decarburization of the steel.

  14. Enhanced humification by carbonated basic oxygen furnace steel slag--II. Process characterization and the role of inorganic components in the formation of humic-like substances.

    PubMed

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

    2012-06-01

    Enhanced humification by abiotic catalysts is a potentially promising supplementary composting method for stabilizing organic carbon from biowastes. In this study, the role of steel slag in the transformation of humic precursors was directly characterized by measuring the variance in dissolved organic carbon (DOC), spectroscopic parameters (E(600)), and the concentration and molecular weight change of humic-like substances (HLS) during the process. In addition, a mechanistic study of the process was explored. The results directly showed that steel slag greatly accelerated the formation of HLS. The findings indicate that Fe(III)-and Mn(IV)-oxides in steel slag act as oxidants and substantially enhance the polycondensation of humic precursors. Moreover, the reaction appears to suppress the release of metals from steel slag to a certain extent under acidic conditions. This can be attributed to the cover of HLS on the external surface of steel slag, which is significant for its environmentally sound reuse.

  15. Maintaining vacuum furnaces

    SciTech Connect

    Kowalewski, J.

    2000-04-01

    A preventive maintenance program is essential for safe and consistent vacuum furnace operation. The program should be developed in cooperation with safety, maintenance, and furnace operators, implemented as soon as the furnace is commissioned, and adhered to throughout the life of the furnace. This article serves as an introduction to the topic of vacuum furnace preventive maintenance. Basic information about installing a new vacuum furnace also is provided.

  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. Direct Observations of Austenite, Bainite and Martensite Formation During Arc Welding of 1045 Steel using Time Resolved X-Ray Diffraction

    SciTech Connect

    Elmer, J; Palmer, T; Babu, S; Zhang, W; DebRoy, T

    2004-02-17

    In-situ Time Resolved X-Ray Diffraction (TRXRD) experiments were performed during stationary gas tungsten arc (GTA) welding of AISI 1045 C-Mn steel. These synchrotron-based experiments tracked, in real time, phase transformations in the heat-affected zone of the weld under rapid heating and cooling conditions. The diffraction patterns were recorded at 100 ms intervals, and were later analyzed using diffraction peak profile analysis to determine the relative fraction of ferrite ({alpha}) and austenite ({gamma}) phases in each diffraction pattern. Lattice parameters and diffraction peak widths were also measured throughout the heating and cooling cycle of the weld, providing additional information about the phases that were formed. The experimental results were coupled with a thermofluid weld model to calculate the weld temperatures, allowing time-temperature transformation kinetics of the {alpha} {yields} {gamma} phase transformation to be evaluated. During heating, complete austenitization was observed in the heat affected zone of the weld and the kinetics of the {alpha} {yields} {gamma} phase transformation were modeled using a Johnson-Mehl-Avrami (JMA) approach. The results from the 1045 steel weld were compared to those of a 1005 low carbon steel from a previous study. Differences in austenitization rates of the two steels were attributed to differences in the base metal microstructures, particularly the relative amounts of pearlite and the extent of the allotriomorphic ferrite phase. During weld cooling, the austenite transformed to a mixture of bainite and martensite. In situ diffraction was able to distinguish between these two non-equilibrium phases based on differences in their lattice parameters and their transformation rates, resulting in the first real time x-ray diffraction observations of bainite and martensite formation made during welding.

  18. Predicting the dilution of plasma transferred arc hardfacing of stellite on carbon steel using response surface methodology

    NASA Astrophysics Data System (ADS)

    Lakshminarayanan, A. K.; Balasubramanian, V.; Varahamoorthy, R.; Babu, S.

    2008-12-01

    Control of dilution is important in hardfacing, where low dilution is typically desirable. At present, most fabrication industries use shielded metal are welding, gas metal arc welding, gas tungsten arc welding and submerged are welding processes for hardfacing purposes. In these processes, the percentage of the dilution level is higher, ranging between 10% and 30%. In Plasma Transferred Arc (PTA) hardfacing, a solidified metallurgical bond between the deposit and the substrate is obtained with minimum dilution (less than 10%). This paper highlights the application of response surface methodology to predict and optimize the percentage of the dilution of a cobalt-based hardfaced surface produced by the PTA process. Experiments were conducted based on a fully replicable five-factor, five-level central composite rotatable design and a mathematical model was developed using response surface methodology. Furthermore, the response surface methodology was used to optimize the process parameters that yield the lowest percentage of dilution.

  19. A Study on the Application of Submerged Arc Welding for Thin Plate of A-Grade 3.2 Thickness Steel in Ship Structure

    NASA Astrophysics Data System (ADS)

    Lee, Jeong-Soo; Yun, Jin-Oh; Lim, Dong-Yong; Jang, Yong-Won; Kim, Bong-Joon; Oh, Chong-In

    2010-06-01

    This paper is focused on application submerged arc welding process, which offers many advantages compared to conventional CO2 welding process, for thin plate in ship structure. For this purpose, optimized welding conditions are determined according to combination of wire & flux, relationship between welding parameters, bead shapes and mechanical tests such as tensile, bend and hardness. Also finite element(FE) based numerical simulation of thermal history and welding residual stress in welded joint of A-grade 3.2 thickness steel has been checked to qualitative tendency in this paper. In conclusion our company applied to this method in work piece and it was no problem. From the result of this study, it makes substantial saving of time and manufacturing cost and raises the welding quality of product.

  20. Preparation and evaluation of submerged-arc weld in 4 inch thick 3Cr-1. 5Mo-0. 1V steel plate. Final report

    SciTech Connect

    Wada, T.; Cox, T.B.

    1983-12-15

    A 79-pass submerged-arc weld joint was prepared in a 4-inch thick 3Cr-1.5Mo-0.1V steel plate using welding wire with a composition similar to the base plate. Welding was made without difficulty, and no cracking was observed after stress relieving at 1175 F (635 C) for 4 hours. After stress relieving to tensile strength levels of 80 to 110 ksi (550 to 760 Mpa), tensile and Charpy impact properties of the weld metal and the heat-affected zone (HAZ) were determined. The HAZ exhibited virtually the same tensile strength and toughness as the base plate. The weld metal exhibited somewhat lower toughness, while its tensile strength was equivalent to that of the base plate.

  1. 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.

  2. Industrial furnace

    SciTech Connect

    Shostak, V.M.; Tolochko, A.I.; Volkov, V.P.; Maradudin, G.I.; Schekin, N.G.; Popov, M.I.; Shepelev, D.N.; Matveev, A.I.; Butnyakov, A.I.; Rzhavichev, A.P.

    1986-09-02

    An industrial furnace is described which consists of: a bath made of a refractory material for filling with a melt; a direct current source; main current-carrying elements having free ends extending to an operating area of the refractory material of the bath below and above the melt, and the main current-carrying elements extending to the operating area below the melt being connected with opposite terminals of the current source from the main current-carrying elements extending to the operating area above the melt; and additional current-carrying elements having free ends sunk in the refractory material of the bath below and above the melt and the additional current-carrying elements being connected with the terminals of the power source of opposite polarity with respect to the connection of the main current-carrying elements of a corresponding part of the operating area.

  3. 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

  4. INTERIOR VIEW LOOKING SOUTHWEST, SHOWING HEROULT NO. 2 FURNACE (ca. ...

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

    INTERIOR VIEW LOOKING SOUTHWEST, SHOWING HEROULT NO. 2 FURNACE (ca. 1920) AND DC MOTORS (which raise and lower the bus bars) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  5. INTERIOR VIEW LOOKING SOUTHWEST SHOWING NO. 1 FURNACE. TO RIGHT ...

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

    INTERIOR VIEW LOOKING SOUTHWEST SHOWING NO. 1 FURNACE. TO RIGHT ARE D.C. MOTORS (which raise and lower the bus bars) - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  6. 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

  7. 38. Base of No. 2 Furnace showing iron runner to ...

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

    38. Base of No. 2 Furnace showing iron runner to ladle car on floor of casting shed. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  8. 39. Detail view of No. 2 Furnace iron runner; rod ...

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

    39. Detail view of No. 2 Furnace iron runner; rod or poker at right was used to unplug iron notch. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  9. The upset machine and furnace in bay 24 of the ...

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

    The upset machine and furnace in bay 24 of the main pipe mill building looking north. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  10. The normalizing furnace and transfer table in bay 24 of ...

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

    The normalizing furnace and transfer table in bay 24 of the main pipe mill building looking east. - U.S. Steel National Tube Works, Skelp Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  11. The normalizing furnace and transfer table in bay 24 of ...

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

    The normalizing furnace and transfer table in bay 24 of the main pipe mill building looking east. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  12. 15. DETAILED OBLIQUE VIEW SOUTHWEST OF FURNACE 1, SHOWING COUNTERWEIGHTED ...

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

    15. DETAILED OBLIQUE VIEW SOUTHWEST OF FURNACE 1, SHOWING COUNTER-WEIGHTED PIVOT ARMS TO RAISE AND LOWER DOORS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  13. 21. DETAILED FRONTAL VIEW WEST OF FURNACE 2, SHOWING MOUTHS ...

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

    21. DETAILED FRONTAL VIEW WEST OF FURNACE 2, SHOWING MOUTHS WITH ROLLERS FOR MOVING TRAYS IN AND OUT OF THE OVENS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  14. 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

  15. 1. EXTERIOR VIEW LOOKING NORTHWEST AT BATCH FURNACE BUILDING, 22' ...

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

    1. EXTERIOR VIEW LOOKING NORTHWEST AT BATCH FURNACE BUILDING, 22' BAR MILL BUILDING, AND 22 BAR MILL MOTOR ROOM. - U.S. Steel Duquesne Works, 22-Inch Bar Mill, Along Monongahela River, Duquesne, Allegheny County, PA

  16. VIEW FACING EAST, VIEW FROM RIVER OF BLAST FURNACE NO. ...

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

    VIEW FACING EAST, VIEW FROM RIVER OF BLAST FURNACE NO. 3. DORR THICKENER & ORE BRIDGE AT LEFT, HOT BLAST STOVES & DUST CATCHER CENTER, CAST HOUSE AT RIGHT. - Pittsburgh Steel Company, Monessen Works, Donner Avenue, Monessen, Westmoreland County, PA

  17. 19. DETAILED OBLIQUE VIEW SOUTHSOUTHEAST OF FURNACE 2, SHOWING PLATFORM ...

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

    19. DETAILED OBLIQUE VIEW SOUTH-SOUTHEAST OF FURNACE 2, SHOWING PLATFORM AT UPPER LEFT HOLDING PULLEY SYSTEM AND ELECTRIC MOTOR TO ACTIVATE DOORS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

  18. 7. NO. 2 CONTINUOUS SLAB REHEATING FURNACE OF THE 160' ...

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

    7. NO. 2 CONTINUOUS SLAB REHEATING FURNACE OF THE 160' PLATE MILL. INTERIOR REFRACTORY LINING VISIBLE BECAUSE OF DEMOLITION. - U.S. Steel Homestead Works, 160" Plate Mill, Along Monongahela River, Homestead, Allegheny County, PA

  19. 44. View looking west down length of No. 2 Furnace ...

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

    44. View looking west down length of No. 2 Furnace casting shed showing overhead traveling crane. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  20. 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

  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. 15. Photocopied June 1978. WHEEL HOUSE RUINS OF 'NEW' FURNACE. ...

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

    15. Photocopied June 1978. WHEEL HOUSE RUINS OF 'NEW' FURNACE. SEGMENT GEAR REMNANTS VISIBLE STANDING IN WHEEL PIT IN FOREGROUND. SOURCE: MCINTYRE DEVELOPMENT, NL INDUSTRIES, TAHAWUS, N.Y. - Adirondack Iron & Steel Company, New Furnace, Hudson River, Tahawus, Essex County, NY

  3. 11. Photocopied June 1978. HOT BLAST STOVE ON 'NEW' FURNACE. ...

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

    11. Photocopied June 1978. HOT BLAST STOVE ON 'NEW' FURNACE. NOTE DOWNCOMER ON LEFT AND DAMPERS ON CHIMNEYS. CA. 1906. SOURCE: MACINTYRE DEVELOPMENT, NL INDUSTRIES, TAHAWUS, N.Y. - Adirondack Iron & Steel Company, New Furnace, Hudson River, Tahawus, Essex County, NY

  4. 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

  5. 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

  6. 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

  7. 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

  8. 17. DETAIL OF THE REMAINS OF BLAST FURNACE No. 2 ...

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

    17. DETAIL OF THE REMAINS OF BLAST FURNACE No. 2 LOOKING EAST. THE BUSTLE PIPE IS VISIBLE ACROSS THE CENTER OF THE IMAGE. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  9. 15. NORTHERN VIEW OF THE REMAINS OF BLAST FURNACE No. ...

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

    15. NORTHERN VIEW OF THE REMAINS OF BLAST FURNACE No. 2 IN LOWER CENTER OF PHOTO AT THE BASE OF HOT BLAST STOVES. HOIST HOUSE No. 2 IS ON THE LEFT. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  10. 5. SOUTHERN VIEW OF BLAST FURNACES No. 3, No. 4, ...

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

    5. SOUTHERN VIEW OF BLAST FURNACES No. 3, No. 4, AND No. 6, WITH ORE YARD IN THE FOREGROUND. BUILDING ON THE LEFT IS THE CENTRAL BOILER HOUSE. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  11. 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

  12. DISCHARGE END OF 8" MILL REHEATING FURNACE, SHOWING MOTOROPERATED PEEL ...

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

    DISCHARGE END OF 8" MILL REHEATING FURNACE, SHOWING MOTOR-OPERATED PEEL BAR PUSHER WITH PINCH ROLLS FOR MOVING BILLETS ENDWISE OUT THE OPPOSITE SIDE OF THE FURNACE TOWARD THE CONTINUOUS ROUGHING TRAIN. - LTV Steel, 8-inch Bar Mill, Buffalo Plant, Buffalo, Erie County, NY

  13. 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

  14. 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

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

    SciTech Connect

    Oden, L.L.; O`Conner, W.K.; Turner, P.C.; Soelberg, N.R.; Anderson, G.L.

    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 melting 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.

  16. 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.

  17. Effect of Bias Voltage on the Fatigue Life of Martensitic Stainless Steel with TiN Film Coated Using Arc Ion Plating Method

    NASA Astrophysics Data System (ADS)

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

    To investigate the effect of 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. A 2-μm-thick TiN film was deposited onto the substrate surface under bias voltage of four kinds: VB = 0, -60, -160 and -260 V. For VB = 0, -160 V and -260 V, the fatigue limit increased. The highest fatigue limit of σmax = 900 MPa was obtained for VB = -160 V. But some samples for VB = -260 V showed the decrease of fatigue limit due to film delamination during the fatigue test. For VB = -60 V, the fatigue limit was unchanged by coating. As a result of a coating property analysis, the following conclusions were obtained. Fatigue crack propagation was almost independent of the bias voltage. Fatigue crack initiated from the subsurface in the substrate and the crack initiation behavior depended on the film property of the adhesion, residual stress, elastic modulus, and the film's hardness depended on the bias voltage especially for low fatigue stress level.

  18. Parameters optimization of hybrid fiber laser-arc butt welding on 316L stainless steel using Kriging model and GA

    NASA Astrophysics Data System (ADS)

    Gao, Zhongmei; Shao, Xinyu; Jiang, Ping; Cao, Longchao; Zhou, Qi; Yue, Chen; Liu, Yang; Wang, Chunming

    2016-09-01

    It is of great significance to select appropriate welding process parameters for obtaining optimal weld geometry in hybrid laser-arc welding. An integrated optimization approach by combining Kriging model and GA is proposed to optimize process parameters. A four-factor, five-level experiment using Taguchi L25 is conducted considering laser power (P), welding current (A), distance between laser and arc (D) and traveling speed (V). Kriging model is adopted to approximate the relationship between process parameters and weld geometry, namely depth of penetration (DP), bead width (BW) and bead reinforcement (BR). The constructed Kriging model was used for parameters optimization by GA to maximize DP, minimize BW and ensure BR at a desired value. The effects of process parameters on weld geometry are analyzed. Microstructure and micro-hardness are also discussed. Verification experiments demonstrate that the obtained optimum values are in good agreement with experimental results.

  19. 13. Blast furnace plant embraces the east bank of the ...

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

    13. Blast furnace plant embraces the east bank of the Cuyahoga River. Plant was established in 1881 by the Cleveland Rolling Mill Co. It was absorbed by the American Steel and Wire Co. in 1899 and, two years later, by the U.S. Steel Corp., which closed it in 1978. View looking north. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  20. Gravitational effects on the weld pool shape and microstructural evolution during gas tungsten arc and laser beam welding of 304 stainless steel and Al-4 wt% Cu alloy.

    PubMed

    Kang, Namhyun; Singh, Jogender; Kulkarni, Anil K

    2004-11-01

    Effects of gravitational acceleration were investigated on the weld pool shape and microstructural evolution for 304 stainless steel and Al-4wt% Cu alloy. Effects of welding heat source were investigated by using laser beam welding (LBW) and gas tungsten arc welding (GTAW). As the gravitational level was increased from low gravity (LG approximately 1.2 g) to high gravity (HG approximately 1.8 g) using a NASA KC-135 aircraft, the weld pool shape for 304 stainless steel was influenced considerably during GTAW. However, insignificant change in the microstructure and solute distribution was observed at gravitational levels between LG and HG. The GTAW on Al-4 wt% Cu alloy was used to investigate the effect of gravitational orientation on the weld solidification behavior. Gravitational orientation was manipulated by varying the welding direction with respect to gravity vector; that is, by welding upward opposing gravity ( ||-U) and downward with gravity ( ||-D) on a vertical weld piece and welding perpendicular to gravity (perpendicular) on a horizontal weld piece. Under the same welding conditions, a larger primary dendrite spacing in the ||-U weld was observed near the weld pool surface and the fusion boundary than in the case of perpendicular or ||-D welds. The ||-D weld exhibited different solidification morphology and abnormal S shape of solidification rate curve during its growth. For 304 stainless steel GTAW, significant effects of gravitational orientation were observed on the weld pool shape that was associated with weld surface morphology and convection flow. However, the weld pool shape for LBW was mostly constant with respect to the gravitational orientation.