Learning Activity Packets for Milling Machines. Unit II--Horizontal Milling Machines.

ERIC Educational Resources Information Center

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This learning activity packet (LAP) outlines the study activities and performance tasks covered in a related curriculum guide on milling machines. The course of study in this LAP is intended to help students learn to set up and operate a horizontal mill. Tasks addressed in the LAP include mounting style "A" or "B" arbors and adjusting arbor…

9. VIEW OF MILLING AND LATHE MACHINES, MILLING AND LATHE ...

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

9. VIEW OF MILLING AND LATHE MACHINES, MILLING AND LATHE MACHINES WERE USED TO FORM COMPONENTS INTO THEIR FINAL SHAPE. IN THE FOUNDRY, ENRICHED URANIUM WAS CAST INTO SPHERICAL SHAPES OR INGOT FROM WHICH WEAPONS COMPONENTS WERE FABRICATED. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

Two-component end mills with multilayer composite nano-structured coatings as a viable alternative to monolithic carbide end mills

NASA Astrophysics Data System (ADS)

Vereschaka, Alexey; Mokritskii, Boris; Mokritskaya, Elena; Sharipov, Oleg; Oganyan, Maksim

2018-03-01

The paper deals with the challenges of the application of two-component end mills, which represent a combination of a carbide cutting part and a shank made of cheaper structural material. The calculations of strains and deformations of composite mills were carried out in comparison with solid carbide mills, with the use of the finite element method. The study also involved the comparative analysis of accuracy parameters of machining with monolithic mills and two-component mills with various shank materials. As a result of the conducted cutting tests in milling aluminum alloy with monolithic and two-component end mills with specially developed multilayer composite nano-structured coatings, it has been found that the use of such coatings can reduce strains and, correspondingly, deformations, which can improve the accuracy of machining. Thus, the application of two-component end mills with multilayer composite nano-structured coatings can provide a reduction in the cost of machining while maintaining or even improving the tool life and machining accuracy parameters.

Neural networks with fuzzy Petri nets for modeling a machining process

NASA Astrophysics Data System (ADS)

Hanna, Moheb M.

1998-03-01

The paper presents an intelligent architecture based a feedforward neural network with fuzzy Petri nets for modeling product quality in a CNC machining center. It discusses how the proposed architecture can be used for modeling, monitoring and control a product quality specification such as surface roughness. The surface roughness represents the output quality specification manufactured by a CNC machining center as a result of a milling process. The neural network approach employed the selected input parameters which defined by the machine operator via the CNC code. The fuzzy Petri nets approach utilized the exact input milling parameters, such as spindle speed, feed rate, tool diameter and coolant (off/on), which can be obtained via the machine or sensors system. An aim of the proposed architecture is to model the demanded quality of surface roughness as high, medium or low.

Experimental investigations on cryogenic cooling by liquid nitrogen in the end milling of hardened steel

NASA Astrophysics Data System (ADS)

Ravi, S.; Pradeep Kumar, M.

2011-09-01

Milling of hardened steel generates excessive heat during the chip formation process, which increases the temperature of cutting tool and accelerates tool wear. Application of conventional cutting fluid in milling process may not effectively control the heat generation also it has inherent health and environmental problems. To minimize health hazard and environmental problems caused by using conventional cutting fluid, a cryogenic cooling set up is developed to cool tool-chip interface using liquid nitrogen (LN 2). This paper presents results on the effect of LN 2 as a coolant on machinability of hardened AISI H13 tool steel for varying cutting speed in the range of 75-125 m/min during end milling with PVD TiAlN coated carbide inserts at a constant feed rate. The results show that machining with LN 2 lowers cutting temperature, tool flank wear, surface roughness and cutting forces as compared with dry and wet machining. With LN 2 cooling, it has been found that the cutting temperature was reduced by 57-60% and 37-42%; the tool flank wear was reduced by 29-34% and 10-12%; the surface roughness was decreased by 33-40% and 25-29% compared to dry and wet machining. The cutting forces also decreased moderately compared to dry and wet machining. This can be attributed to the fact that LN 2 machining provides better cooling and lubrication through substantial reduction in the cutting zone temperature.

Surface topography and roughness of high-speed milled AlMn1Cu

NASA Astrophysics Data System (ADS)

Wang, Zhenhua; Yuan, Juntang; Yin, Zengbin; Hu, Xiaoqiu

2016-10-01

The aluminum alloy AlMn1Cu has been broadly applied for functional parts production because of its good properties. But few researches about the machining mechanism and the surface roughness were reported. The high-speed milling experiments are carried out in order to improve the machining quality and reveal the machining mechanism. The typical topography features of machined surface are observed by scan electron microscope(SEM). The results show that the milled surface topography is mainly characterized by the plastic shearing deformation surface and material piling zone. The material flows plastically along the end cutting edge of the flat-end milling tool and meanwhile is extruded by the end cutting edge, resulting in that materials partly adhere to the machined surface and form the material piling zone. As the depth of cut and the feed per tooth increase, the plastic flow of materials is strengthened and the machined surface becomes rougher. However, as the cutting speed increases, the plastic flow of materials is weakened and the milled surface becomes smoother. The cutting parameters (e.g. cutting speed, feed per tooth and depth of cut) influencing the surface roughness are analyzed. It can be concluded that the roughness of the machined surface formed by the end cutting edge is less than that by the cylindrical cutting edge when a cylindrical flat-end mill tool is used for milling. The proposed research provides the typical topography features of machined surface of the anti-rust aluminum alloy AlMn1Cu in high speed milling.

Computer Programmed Milling Machine Operations. High-Technology Training Module.

ERIC Educational Resources Information Center

Leonard, Dennis

This learning module for a high school metals and manufacturing course is designed to introduce the concept of computer-assisted machining (CAM). Through it, students learn how to set up and put data into the controller to machine a part. They also become familiar with computer-aided manufacturing and learn the advantages of computer numerical…

Apparatus for cutting elastomeric materials

NASA Technical Reports Server (NTRS)

Corbett, A. B.

1974-01-01

Sharp thin cutting edge is held in head of milling machine designed for metal working. Controls of machine are used to position cutting edge in same plane as vibrating specimen. Controls then are operated, making blade come into contact with specimen, to cut it into shapes and sizes desired. Cut surfaces appear mirror-smooth; vibrating mechanism causes no visible striations.

Biofuel manufacturing from woody biomass: effects of sieve size used in biomass size reduction.

PubMed

Zhang, Meng; Song, Xiaoxu; Deines, T W; Pei, Z J; Wang, Donghai

2012-01-01

Size reduction is the first step for manufacturing biofuels from woody biomass. It is usually performed using milling machines and the particle size is controlled by the size of the sieve installed on a milling machine. There are reported studies about the effects of sieve size on energy consumption in milling of woody biomass. These studies show that energy consumption increased dramatically as sieve size became smaller. However, in these studies, the sugar yield (proportional to biofuel yield) in hydrolysis of the milled woody biomass was not measured. The lack of comprehensive studies about the effects of sieve size on energy consumption in biomass milling and sugar yield in hydrolysis process makes it difficult to decide which sieve size should be selected in order to minimize the energy consumption in size reduction and maximize the sugar yield in hydrolysis. The purpose of this paper is to fill this gap in the literature. In this paper, knife milling of poplar wood was conducted using sieves of three sizes (1, 2, and 4 mm). Results show that, as sieve size increased, energy consumption in knife milling decreased and sugar yield in hydrolysis increased in the tested range of particle sizes.

Design and fabrication of complete dentures using CAD/CAM technology

PubMed Central

Han, Weili; Li, Yanfeng; Zhang, Yue; lv, Yuan; Zhang, Ying; Hu, Ping; Liu, Huanyue; Ma, Zheng; Shen, Yi

2017-01-01

Abstract The aim of the study was to test the feasibility of using commercially available computer-aided design and computer-aided manufacturing (CAD/CAM) technology including 3Shape Dental System 2013 trial version, WIELAND V2.0.049 and WIELAND ZENOTEC T1 milling machine to design and fabricate complete dentures. The modeling process of full denture available in the trial version of 3Shape Dental System 2013 was used to design virtual complete dentures on the basis of 3-dimensional (3D) digital edentulous models generated from the physical models. The virtual complete dentures designed were exported to CAM software of WIELAND V2.0.049. A WIELAND ZENOTEC T1 milling machine controlled by the CAM software was used to fabricate physical dentitions and baseplates by milling acrylic resin composite plates. The physical dentitions were bonded to the corresponding baseplates to form the maxillary and mandibular complete dentures. Virtual complete dentures were successfully designed using the software through several steps including generation of 3D digital edentulous models, model analysis, arrangement of artificial teeth, trimming relief area, and occlusal adjustment. Physical dentitions and baseplates were successfully fabricated according to the designed virtual complete dentures using milling machine controlled by a CAM software. Bonding physical dentitions to the corresponding baseplates generated the final physical complete dentures. Our study demonstrated that complete dentures could be successfully designed and fabricated by using CAD/CAM. PMID:28072686

The infrared camera application for calculating the impact of the feed screw thermal expansion on machining accuracy

NASA Astrophysics Data System (ADS)

Matras, A.

2017-08-01

The paper discusses the impact of the feed screw heating on the machining accuracy. The test stand was built based on HASS Mini Mill 2 CNC milling machine and a Flir SC620 infrared camera. Measurements of workpiece were performed on Talysurf Intra 50 Taylor Hobson profilometer. The research proved that the intensive work of the milling machine lasted 60 minutes, causing thermal expansion of the feed screw what influence on the dimension error of the workpiece.

The Tool Life of Ball Nose end Mill Depending on the Different Types of Ramping

NASA Astrophysics Data System (ADS)

Vopát, Tomáš; Peterka, Jozef; Kováč, Martin

2014-12-01

The article deals with the cutting tool wear measurement process and tool life of ball nose end mill depending on upward ramping and downward ramping. The aim was to determine and compare the wear (tool life) of ball nose end mill for different types of copy milling operations, as well as to specify particular steps of the measurement process. In addition, we examined and observed cutter contact areas of ball nose end mill with machined material. For tool life test, DMG DMU 85 monoBLOCK 5-axis CNC milling machine was used. In the experiment, cutting speed, feed rate, axial depth of cut and radial depth of cut were not changed. The cutting tool wear was measured on Zoller Genius 3s universal measuring machine. The results show different tool life of ball nose end mills depending on the copy milling strategy.

Modelling of End Milling of AA6061-TiCp Metal Matrix Composite

NASA Astrophysics Data System (ADS)

Vijay Kumar, S.; Cheepu, Muralimohan; Venkateswarlu, D.; Asohan, P.; Senthil Kumar, V.

2018-03-01

The metal-matrix composites (MMCs) are used in various applications hence lot of research has been carried out on MMCs. To increase the properties of Albased MMCs many ceramic reinforcements have been identified, among which TiC is played vital role because of its properties like high hardness, stiffness and wear resistance. In the present work, a neural network and statistical modelling approach is going to use for the prediction of surface roughness (Ra) and cutting forces in computerised numerical control milling machine. Experiments conducted on a CNC milling machine based on the full factorial design and resulted data used to train and checking the network performance. The sample prepared from in-situ technique and heat treated to get uniform properties. The ANN model has shown satisfactory performance comparatively.

Modelling of End Milling of AA6061-TiCp Metal Matrix Composite

NASA Astrophysics Data System (ADS)

Vijay Kumar, S.; Cheepu, Muralimohan; Venkateswarlu, D.; Asohan, P.; Senthil Kumar, V.

2018-03-01

The metal-matrix composites (MMCs) are used in various applications hence lot of research has been carried out on MMCs. To increase the properties of Al-based MMCs many ceramic reinforcements have been identified, among which TiC is played vital role because of its properties like high hardness, stiffness and wear resistance. In the present work, a neural network and statistical modelling approach is going to use for the prediction of surface roughness (Ra) and cutting forces in computerised numerical control milling machine. Experiments conducted on a CNC milling machine based on the full factorial design and resulted data used to train and checking the network performance. The sample prepared from in-situ technique and heat treated to get uniform properties. The ANN model has shown satisfactory performance comparatively.

Nozzles for Focusing Aerosol Particles

DTIC Science & Technology

2009-10-01

Fabrication of the nozzle with the desired shape was accomplished using EDM technology. First, a copper tungsten electrode was turned on a CNC lathe . The...small (0.9-mm diameter). The external portions of the nozzles were machined in a more conventional manner using computer numerical control ( CNC ... lathes and milling machines running programs written by computer aided machining (CAM) software. The close tolerance of concentricity of the two

Micro electrical discharge milling using deionized water as a dielectric fluid

NASA Astrophysics Data System (ADS)

Chung, Do Kwan; Kim, Bo Hyun; Chu, Chong Nam

2007-05-01

In electrical discharge machining, dielectric fluid is an important factor affecting machining characteristics. Generally, kerosene and deionized water have been used as dielectric fluids. In micro electrical discharge milling, which uses a micro electrode as a tool, the wear of the tool electrode decreases the machining accuracy. However, the use of deionized water instead of kerosene can reduce the tool wear and increase the machining speed. This paper investigates micro electrical discharge milling using deionized water. Deionized water with high resistivity was used to minimize the machining gap. Machining characteristics such as the tool wear, machining gap and machining rate were investigated according to resistivity of deionized water. As the resistivity of deionized water decreased, the tool wear was reduced, but the machining gap increased due to electrochemical dissolution. Micro hemispheres were machined for the purpose of investigating machining efficiency between dielectric fluids, kerosene and deionized water.

Motion Simulation Analysis of Rail Weld CNC Fine Milling Machine

NASA Astrophysics Data System (ADS)

Mao, Huajie; Shu, Min; Li, Chao; Zhang, Baojun

CNC fine milling machine is a new advanced equipment of rail weld precision machining with high precision, high efficiency, low environmental pollution and other technical advantages. The motion performance of this machine directly affects its machining accuracy and stability, which makes it an important consideration for its design. Based on the design drawings, this article completed 3D modeling of 60mm/kg rail weld CNC fine milling machine by using Solidworks. After that, the geometry was imported into Adams to finish the motion simulation analysis. The displacement, velocity, angular velocity and some other kinematical parameters curves of the main components were obtained in the post-processing and these are the scientific basis for the design and development for this machine.

Performance of Color Camera Machine Vision in Automated Furniture Rough Mill Systems

Treesearch

D. Earl Kline; Agus Widoyoko; Janice K. Wiedenbeck; Philip A. Araman

1998-01-01

The objective of this study was to evaluate the performance of color camera machine vision for lumber processing in a furniture rough mill. The study used 134 red oak boards to compare the performance of automated gang-rip-first rough mill yield based on a prototype color camera lumber inspection system developed at Virginia Tech with both estimated optimum rough mill...

Tool setting device

DOEpatents

Brown, Raymond J.

1977-01-01

The present invention relates to a tool setting device for use with numerically controlled machine tools, such as lathes and milling machines. A reference position of the machine tool relative to the workpiece along both the X and Y axes is utilized by the control circuit for driving the tool through its program. This reference position is determined for both axes by displacing a single linear variable displacement transducer (LVDT) with the machine tool through a T-shaped pivotal bar. The use of the T-shaped bar allows the cutting tool to be moved sequentially in the X or Y direction for indicating the actual position of the machine tool relative to the predetermined desired position in the numerical control circuit by using a single LVDT.

Predictive Surface Roughness Model for End Milling of Machinable Glass Ceramic

NASA Astrophysics Data System (ADS)

Mohan Reddy, M.; Gorin, Alexander; Abou-El-Hossein, K. A.

2011-02-01

Advanced ceramics of Machinable glass ceramic is attractive material to produce high accuracy miniaturized components for many applications in various industries such as aerospace, electronics, biomedical, automotive and environmental communications due to their wear resistance, high hardness, high compressive strength, good corrosion resistance and excellent high temperature properties. Many research works have been conducted in the last few years to investigate the performance of different machining operations when processing various advanced ceramics. Micro end-milling is one of the machining methods to meet the demand of micro parts. Selecting proper machining parameters are important to obtain good surface finish during machining of Machinable glass ceramic. Therefore, this paper describes the development of predictive model for the surface roughness of Machinable glass ceramic in terms of speed, feed rate by using micro end-milling operation.

Are different generations of CAD/CAM milling machines capable to produce restorations with similar quality?

PubMed

Roperto, Renato; Assaf, Hussein; Soares-Porto, Thiago; Lang, Lisa; Teich, Sorin

2016-10-01

Different CAD/CAM machines' generation may impact the restoration overall quality. The present study evaluated the marginal fit of CAD/CAM restorations manufactured with different generations of CEREC milling unit systems. Sixteen typodont teeth were divided into two groups (n=8) according to the machine's generation assigned. These are control group (G1): Cerec AC with Bluecam/Cerec 3 milling unit and (G2): Cerec AC with Bluecam/MC XL Premium Package milling unit. Scanning of the preparation were performed and crowns were milled using the Vita Mark II blocks. Blocks were cemented using epoxy glue on the pulpal floor only and finger pressure applied for 1 min. Upon completion of the cementation step, misfits between the restoration and abutment were measured by microphotography and the silicone replica technique using light body silicon material on Mesial (M) and Distal (D) surfaces. Mean and SDs of marginal gaps in micrometers were: G1/M: 94.90 (±38.52), G1/D: 88.53 (±44.87), G2/M: 85.65 (±29.89), G2/D: 95.28 (±28.13). Two-way ANOVA indicated no significant differences among different groups ( P >0.05); surface area ( P >0.05) and the interaction ( P >0.05). Overall, G2 had greater margin gaps than G1, however, without statistical difference ( P >0.05). Difference in milling unit generation did not significantly affect the marginal fit. Marginal gap means were in the range of the clinical acceptance levels for both generations of Cerec milling units, regardless the teeth site area. Key words: CAD/CAM, margin, ceramics.

Rock sampling. [method for controlling particle size distribution

NASA Technical Reports Server (NTRS)

Blum, P. (Inventor)

1971-01-01

A method for sampling rock and other brittle materials and for controlling resultant particle sizes is described. The method involves cutting grooves in the rock surface to provide a grouping of parallel ridges and subsequently machining the ridges to provide a powder specimen. The machining step may comprise milling, drilling, lathe cutting or the like; but a planing step is advantageous. Control of the particle size distribution is effected primarily by changing the height and width of these ridges. This control exceeds that obtainable by conventional grinding.

48 CFR 9904.409-60 - Illustrations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the provisions of this Standard. (a) Companies X, Y, and Z purchase identical milling machines to be... individual asset basis. Its experience with similar machines is that the average replacement period is 14... for the milling machine unless it can demonstrate changed circumstances or new circumstances to...

48 CFR 9904.409-60 - Illustrations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the provisions of this Standard. (a) Companies X, Y, and Z purchase identical milling machines to be... individual asset basis. Its experience with similar machines is that the average replacement period is 14... for the milling machine unless it can demonstrate changed circumstances or new circumstances to...

48 CFR 9904.409-60 - Illustrations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the provisions of this Standard. (a) Companies X, Y, and Z purchase identical milling machines to be... individual asset basis. Its experience with similar machines is that the average replacement period is 14... for the milling machine unless it can demonstrate changed circumstances or new circumstances to...

VIEW OF TURNTABLE, WITH CAR MACHINE SHOP AND PLANING MILL ...

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

VIEW OF TURNTABLE, WITH CAR MACHINE SHOP AND PLANING MILL IN THE BACKGROUND AND ERECTING/MACHINE SHOP AT RIGHT, LOOKING EAST. ATSF 5021 2-10-4 STEAM LOCOMOTIVE IS ON TURNTABLE. - Southern Pacific, Sacramento Shops, 111 I Street, Sacramento, Sacramento County, CA

Chip morphology as a performance predictor during high speed end milling of soda lime glass

NASA Astrophysics Data System (ADS)

Bagum, M. N.; Konneh, M.; Abdullah, K. A.; Ali, M. Y.

2018-01-01

Soda lime glass has application in DNA arrays and lab on chip manufacturing. Although investigation revealed that machining of such brittle material is possible using ductile mode under controlled cutting parameters and tool geometry, it remains a challenging task. Furthermore, ability of ductile machining is usually assed through machined surface texture examination. Soda lime glass is a strain rate and temperature sensitive material. Hence, influence on attainment of ductile surface due to adiabatic heat generated during high speed end milling using uncoated tungsten carbide tool is investigated in this research. Experimental runs were designed using central composite design (CCD), taking spindle speed, feed rate and depth of cut as input variable and tool-chip contact point temperature (Ttc) and the surface roughness (Rt) as responses. Along with machined surface texture, Rt and chip morphology was examined to assess machinability of soda lime glass. The relation between Ttc and chip morphology was examined. Investigation showed that around glass transition temperature (Tg) ductile chip produced and subsequently clean and ductile final machined surface produced.

Experiments on robot-assisted navigated drilling and milling of bones for pedicle screw placement.

PubMed

Ortmaier, T; Weiss, H; Döbele, S; Schreiber, U

2006-12-01

This article presents experimental results for robot-assisted navigated drilling and milling for pedicle screw placement. The preliminary study was carried out in order to gain first insights into positioning accuracies and machining forces during hands-on robotic spine surgery. Additionally, the results formed the basis for the development of a new robot for surgery. A simplified anatomical model is used to derive the accuracy requirements. The experimental set-up consists of a navigation system and an impedance-controlled light-weight robot holding the surgical instrument. The navigation system is used to position the surgical instrument and to compensate for pose errors during machining. Holes are drilled in artificial bone and bovine spine. A quantitative comparison of the drill-hole diameters was achieved using a computer. The interaction forces and pose errors are discussed with respect to the chosen machining technology and control parameters. Within the technological boundaries of the experimental set-up, it is shown that the accuracy requirements can be met and that milling is superior to drilling. It is expected that robot assisted navigated surgery helps to improve the reliability of surgical procedures. Further experiments are necessary to take the whole workflow into account. Copyright 2006 John Wiley & Sons, Ltd.

An In-Process Surface Roughness Recognition System in End Milling Operations

ERIC Educational Resources Information Center

Yang, Lieh-Dai; Chen, Joseph C.

2004-01-01

To develop an in-process quality control system, a sensor technique and a decision-making algorithm need to be applied during machining operations. Several sensor techniques have been used in the in-process prediction of quality characteristics in machining operations. For example, an accelerometer sensor can be used to monitor the vibration of…

Investigation of Carbon Fiber Reinforced Plastics Machining Using 355 nm Picosecond Pulsed Laser

NASA Astrophysics Data System (ADS)

Hu, Jun; Zhu, Dezhi

2018-06-01

Carbon fiber reinforced plastics (CFRP) has been widely used in the aircraft industry and automobile industry owing to its superior properties. In this paper, a Nd:YVO4 picosecond pulsed system emitting at 355 nm has been used for CFRP machining experiments to determine optimum milling conditions. Milling parameters including laser power, milling speed and hatch distance were optimized by using box-behnken design of response surface methodology (RSM). Material removal rate was influenced by laser beam overlap ratio which affects mechanical denudation. The results in heat affected zones (HAZ) and milling quality were discussed through the machined surface observed with scanning electron microscope. A re-focusing technique based on the experiment with different focal planes was proposed and milling mechanism was also analyzed in details.

The study on dynamic properties of monolithic ball end mills with various slenderness

NASA Astrophysics Data System (ADS)

Wojciechowski, Szymon; Tabaszewski, Maciej; Krolczyk, Grzegorz M.; Maruda, Radosław W.

2017-10-01

The reliable determination of modal mass, damping and stiffness coefficient (modal parameters) for the particular machine-toolholder-tool system is essential for the accurate estimation of vibrations, stability and thus the machined surface finish formed during the milling process. Therefore, this paper focuses on the analysis of ball end mill's dynamical properties. The tools investigated during this study are monolithic ball end mills with different slenderness values, made of coated cemented carbide. These kinds of tools are very often applied during the precise milling of curvilinear surfaces. The research program included the impulse test carried out for the investigated tools clamped in the hydraulic toolholder. The obtained modal parameters were further applied in the developed tool's instantaneous deflection model, in order to estimate the tool's working part vibrations during precise milling. The application of the proposed dynamics model involved also the determination of instantaneous cutting forces on the basis of the mechanistic approach. The research revealed that ball end mill's slenderness can be considered as an important milling dynamics and machined surface quality indicator.

Effect of microstructure on the breakage of tin bronze machining chips during pulverization via jet milling

NASA Astrophysics Data System (ADS)

Afshari, Elham; Ghambari, Mohammad; Farhangi, Hasan

2016-11-01

In this study, jet milling was used to recycle tin bronze machining chips into powder. The main purpose of this study was to assess the effect of the microstructure of tin bronze machining chips on their breakage behavior. An experimental target jet mill was used to pulverize machining chips of three different tin bronze alloys containing 7wt%, 10wt%, and 12wt% of tin. Optical and electron microscopy, as well as sieve analysis, were used to follow the trend of pulverization. Each alloy exhibited a distinct rate of size reduction, particle size distribution, and fracture surface appearance. The results showed that the degree of pulverization substantially increased with increasing tin content. This behavior was attributed to the higher number of machining cracks as well as the increased volume fraction of brittle δ phase in the alloys with higher tin contents. The δ phase was observed to strongly influence the creation of machining cracks as well as the nucleation and propagation of cracks during jet milling. In addition, a direct relationship was observed between the mean δ-phase spacing and the mean size of the jet-milled product; i.e., a decrease in the δ-phase spacing resulted in smaller particles.

Effect of High-speed Milling tool path strategies on the surface roughness of Stavax ESR mold insert machining

NASA Astrophysics Data System (ADS)

Mebrahitom, A.; Rizuan, D.; Azmir, M.; Nassif, M.

2016-02-01

High speed milling is one of the recent technologies used to produce mould inserts due to the need for high surface finish. It is a faster machining process where it uses a small side step and a small down step combined with very high spindle speed and feed rate. In order to effectively use the HSM capabilities, optimizing the tool path strategies and machining parameters is an important issue. In this paper, six different tool path strategies have been investigated on the surface finish and machining time of a rectangular cavities of ESR Stavax material. CAD/CAM application of CATIA V5 machining module for pocket milling of the cavities was used for process planning.

Modeling of Geometric Error in Linear Guide Way to Improved the vertical three-axis CNC Milling machine’s accuracy

NASA Astrophysics Data System (ADS)

Kwintarini, Widiyanti; Wibowo, Agung; Arthaya, Bagus M.; Yuwana Martawirya, Yatna

2018-03-01

The purpose of this study was to improve the accuracy of three-axis CNC Milling Vertical engines with a general approach by using mathematical modeling methods of machine tool geometric errors. The inaccuracy of CNC machines can be caused by geometric errors that are an important factor during the manufacturing process and during the assembly phase, and are factors for being able to build machines with high-accuracy. To improve the accuracy of the three-axis vertical milling machine, by knowing geometric errors and identifying the error position parameters in the machine tool by arranging the mathematical modeling. The geometric error in the machine tool consists of twenty-one error parameters consisting of nine linear error parameters, nine angle error parameters and three perpendicular error parameters. The mathematical modeling approach of geometric error with the calculated alignment error and angle error in the supporting components of the machine motion is linear guide way and linear motion. The purpose of using this mathematical modeling approach is the identification of geometric errors that can be helpful as reference during the design, assembly and maintenance stages to improve the accuracy of CNC machines. Mathematically modeling geometric errors in CNC machine tools can illustrate the relationship between alignment error, position and angle on a linear guide way of three-axis vertical milling machines.

Novel tool wear monitoring method in milling difficult-to-machine materials using cutting chip formation

NASA Astrophysics Data System (ADS)

Zhang, P. P.; Guo, Y.; Wang, B.

2017-05-01

The main problems in milling difficult-to-machine materials are the high cutting temperature and rapid tool wear. However it is impossible to investigate tool wear in machining. Tool wear and cutting chip formation are two of the most important representations for machining efficiency and quality. The purpose of this paper is to develop the model of tool wear with cutting chip formation (width of chip and radian of chip) on difficult-to-machine materials. Thereby tool wear is monitored by cutting chip formation. A milling experiment on the machining centre with three sets cutting parameters was performed to obtain chip formation and tool wear. The experimental results show that tool wear increases gradually along with cutting process. In contrast, width of chip and radian of chip decrease. The model is developed by fitting the experimental data and formula transformations. The most of monitored errors of tool wear by the chip formation are less than 10%. The smallest error is 0.2%. Overall errors by the radian of chip are less than the ones by the width of chip. It is new way to monitor and detect tool wear by cutting chip formation in milling difficult-to-machine materials.

Machinability of experimental Ti-Ag alloys.

PubMed

Kikuchi, Masafumi; Takahashi, Masatoshi; Okuno, Osamu

2008-03-01

This study investigated the machinability of experimental Ti-Ag alloys (5, 10, 20, and 30 mass% Ag) as a new dental titanium alloy candidate for CAD/CAM use. The alloys were slotted with a vertical milling machine and carbide square end mills under two cutting conditions. Machinability was evaluated through cutting force using a three-component force transducer fixed on the table of the milling machine. The horizontal cutting force of the Ti-Ag alloys tended to decrease as the concentration of silver increased. Values of the component of the horizontal cutting force perpendicular to the feed direction for Ti-20% Ag and Ti-30% Ag were more than 20% lower than those for titanium under both cutting conditions. Alloying with silver significantly improved the machinability of titanium in terms of cutting force under the present cutting conditions.

37. MILL NO. 2, 2nd FLOOR, CLOSE SHOT OF 2 ...

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

37. MILL NO. 2, 2nd FLOOR, CLOSE SHOT OF 2 CREEL MACHINES, WHICH FEED YARN INTO KNITTING MACHINES. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

Seminar for High School Students “Practice on Manufacturing Technology by Advanced Machine Tools”

NASA Astrophysics Data System (ADS)

Marui, Etsuo; Yamawaki, Masao; Taga, Yuken; Omoto, Ken'ichi; Miyaji, Reiji; Ogura, Takahiro; Tsubata, Yoko; Sakai, Toshimasa

The seminar ‘Practice on Manufacturing Technology by Advanced Machine Tools’ for high school students was held at the supporting center for technology education of Gifu University, under the sponsorship of the Japan Society of Mechanical Engineers. This seminar was held, hoping that many students become interested in manufacturing through the experience of the seminar. Operating CNC milling machine and CNC wire-cut electric discharge machine, they made original nameplates. Participants made the program to control CNC machine tools themselves. In this report, some valuable results obtained through such experience are explained.

Effet de l'usinage sur les proprietes mecaniques en tension et controle non-destructif des materiaux composites

NASA Astrophysics Data System (ADS)

Genereux, Louis-Alexandre

The main goal of this work is to evaluate the impact of milling operations on the integrity of unidirectional carbon/epoxy laminate. Milling, often used for finishing composite structures, cause some damage in the form of craters, cracks and thermal damage to the matrix. Here, two approaches are used to qualify and quantify the amount of damage. First, two nondestructive testing methods, namely immersion ultrasonic inspection and pulsed thermography, are evaluated on samples with artificial defects. These techniques are then used on machined samples with realistic machining damages. Only ultrasounds allowed the detection and quantification of the machining damages, but only if the damages are at the surface of the laminate. The depth of damage depends primarily on the fiber orientation of the first ply with respect to the cutting direction. The ultrasonic inspections are also accompanied by scanning electron microscope observations. The second approach is to check whether the presence of the machining damage will affect the mechanical properties of the laminate. To do this, static tensile tests are performed on samples prepared by three different methods, namely, by abrasive diamond saw, by saw cut followed by sanding and finally by milling. The results show that the damages caused by the milling operation are not important enough to affect the ultimate stress and elastic modulus. Despite this, it would be interesting, for future works, to investigate this aspect in fatigue rather than with static tests. The presence of damages on the edge might promote delamination during cyclic loads.

Metal Cutting Theory and Friction Stir Welding Tool Design

NASA Technical Reports Server (NTRS)

Payton, Lewis N.

2003-01-01

Friction Stir Welding (FSW) is a relatively new industrial process that was invented at The Weld Institute (TWI, United Kingdom) and patented in 1992 under research funded by in part by the National Aeronautics and Space Administration (NASA). Often quoted advantages of the process include good strength and ductility along with minimization of residual stress and distortion. Less well advertised are the beneficial effects of this solid state welding process in the field of occupational and environmental safety. It produces superior weld products in difficult to weld materials without producing any toxic fumes or solid waste that must be controlled as hazardous waste. In fact, it reduces noise pollution in the workspace as well. In the early days of FSW, most welding was performed on modified machine tools, in particular on milling machines with modified milling cutters. In spite of the obvious milling heritage of the process, the techniques and lessons learned from almost 250 years of successful metalworking with milling machines have not been applied in the field of modern Friction Stir Welding. The goal of the current research was to study currently successful FSW tools and parameterize the process in such a way that the design of new tools for new materials could be accelerated. Along the way, several successful new tooling designs were developed for current issues at the Marshall Space Flight Center with accompanying patent disclosures

Surface integrity and fatigue behaviour of electric discharged machined and milled austenitic stainless steel

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

Lundberg, Mattias, E-mail: mattias.lundberg@liu.se

Machining of austenitic stainless steels can result in different surface integrities and different machining process parameters will have a great impact on the component fatigue life. Understanding how machining processes affect the cyclic behaviour and microstructure are of outmost importance in order to improve existing and new life estimation models. Milling and electrical discharge machining (EDM) have been used to manufacture rectangular four-point bend fatigue test samples; subjected to high cycle fatigue. Before fatigue testing, surface integrity characterisation of the two surface conditions was conducted using scanning electron microscopy, surface roughness, residual stress profiles, and hardness profiles. Differences in cyclicmore » behaviour were observed between the two surface conditions by the fatigue testing. The milled samples exhibited a fatigue limit. EDM samples did not show the same behaviour due to ratcheting. Recrystallized nano sized grains were identified at the severely plastically deformed surface of the milled samples. Large amounts of bent mechanical twins were observed ~ 5 μm below the surface. Grain shearing and subsequent grain rotation from milling bent the mechanical twins. EDM samples showed much less plastic deformation at the surface. Surface tensile residual stresses of ~ 500 MPa and ~ 200 MPa for the milled and EDM samples respectively were measured. - Highlights: •Milled samples exhibit fatigue behaviour, but not EDM samples. •Four-point bending is not suitable for materials exhibiting pronounced ratcheting. •LAGB density can be used to quantitatively measure plastic deformation. •Grain shearing and rotation result in bent mechanical twins. •Nano sized grains evolve due to the heat of the operation.« less

26. OVERALL SHOT OF BASEMENT, MILL NO. 1. ORIGINALLY MACHINE ...

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

26. OVERALL SHOT OF BASEMENT, MILL NO. 1. ORIGINALLY MACHINE SHOP. PALLETS ON FLOOR ADDED IN LATE 20th C. FOR CLOTH STORAGE. - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

INTERIOR OF SECOND FLOOR BRIDGE BETWEEN PLANING MILL AND CAR ...

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

INTERIOR OF SECOND FLOOR BRIDGE BETWEEN PLANING MILL AND CAR MACHINE SHOP, LOOKING SOUTH TOWARD PLANING MILL. - Southern Pacific, Sacramento Shops, Planing Mill, 111 I Street, Sacramento, Sacramento County, CA

Different Techniques For Producing Precision Holes (>20 mm) In Hardened Steel—Comparative Results

NASA Astrophysics Data System (ADS)

Coelho, R. T.; Tanikawa, S. T.

2009-11-01

High speed machining (HSM), or high performance machining, has been one of the most recent technological advances. When applied to milling operations, using adequate machines, CAM programs and tooling, it allows cutting hardened steels, which was not feasible just a couple of years ago. The use of very stiff and precision machines has created the possibilities of machining holes in hardened steels, such as AISI H13 with 48-50 HRC, using helical interpolations, for example. Such process is particularly useful for holes with diameter bigger than normal solid carbide drills commercially available, around 20 mm, or higher. Such holes may need narrow tolerances, fine surface finishing, which can be obtained just by end milling operations. The present work compares some of the strategies used to obtain such holes by end milling, and also some techniques employed to finish them, by milling, boring and also by fine grinding at the same machine. Results indicate that it is possible to obtain holes with less than 0.36 m in circularity, 7.41 m in cylindricity and 0.12 m in surface roughness Ra. Additionally, there is less possibilities of obtaining heat affected layers when using such technique.

Accelerating Industrial Adoption of Metal Additive Manufacturing Technology

NASA Astrophysics Data System (ADS)

Vartanian, Kenneth; McDonald, Tom

2016-03-01

While metal additive manufacturing (AM) technology has clear benefits, there are still factors preventing its adoption by industry. These factors include the high cost of metal AM systems, the difficulty for machinists to learn and operate metal AM machines, the long approval process for part qualification/certification, and the need for better process controls; however, the high AM system cost is the main barrier deterring adoption. In this paper, we will discuss an America Makes-funded program to reduce AM system cost by combining metal AM technology with conventional computerized numerical controlled (CNC) machine tools. Information will be provided on how an Optomec-led team retrofitted a legacy CNC vertical mill with laser engineered net shaping (LENS®—LENS is a registered trademark of Sandia National Labs) AM technology, dramatically lowering deployment cost. The upgraded system, dubbed LENS Hybrid Vertical Mill, enables metal additive and subtractive operations to be performed on the same machine tool and even on the same part. Information on the LENS Hybrid system architecture, learnings from initial system deployment and continuing development work will also be provided to help guide further development activities within the materials community.

Process Capability of High Speed Micro End-Milling of Inconel 718 with Minimum Quantity Lubrication

NASA Astrophysics Data System (ADS)

Rahman, Mohamed Abd; Yeakub Ali, Mohammad; Rahman Shah Rosli, Abdul; Banu, Asfana

2017-03-01

The demand for micro-parts is expected to grow and micro-machining has been shown to be a viable manufacturing process to produce these products. These micro-products may be produced from hard-to-machine materials such as superalloys under little or no metal cutting fluids to reduce machining cost or drawbacks associated with health and environment. This project aims to investigate the capability of micro end-milling process of Inconel 718 with minimum quantity lubrication (MQL). Microtools DT-110 multi-process micro machine was used to machine 10 micro-channels with MQL and 10 more under dry condition while maintaining the same machining parameters. The width of the micro-channels was measured using digital microscope and used to determine the process capability indices, Cp and Cpk. QI Macros SPC for Excel was used to analyze the resultant machining data. The results indicated that micro end-milling process of Inconel 718 was not capable under both MQL and dry cutting conditions as indicated by the Cp values of less than 1.0. However, the use of MQL helped the process to be more stable and capable. Results obtained showed that the process variation was greatly reduced by using MQL in micro end-milling of Inconel 718.

Looking north at the threading machine of the no. 1 ...

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

Looking north at the threading machine of the no. 1 seamless line in bay 11 of the main pipe mill building - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

Highly Productive Tools For Turning And Milling

NASA Astrophysics Data System (ADS)

Vasilko, Karol

2015-12-01

Beside cutting speed, shift is another important parameter of machining. Its considerable influence is shown mainly in the workpiece machined surface microgeometry. In practice, mainly its combination with the radius of cutting tool tip rounding is used. Options to further increase machining productivity and machined surface quality are hidden in this approach. The paper presents variations of the design of productive cutting tools for lathe work and milling on the base of the use of the laws of the relationship among the highest reached uneveness of machined surface, tool tip radius and shift.

10. AERIAL VIEW LOOKING SOUTH SOUTHEAST SHOWING (from left) INDUSTRY ...

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

10. AERIAL VIEW LOOKING SOUTH SOUTHEAST SHOWING (from left) INDUSTRY MILL, HARMONY MILL, PHOENIX MILL, CONGDON MILL, TODD RAFFERTY MACHINE CO. - Great Falls S. U. M. Historic District, Oliver Street, Paterson, Passaic County, NJ

Analysis of the influence of the milling machine throw-out plate surfacing and structure design on throwing material

NASA Astrophysics Data System (ADS)

Fang, Yuanbin; Sha, Hongwei; Yu, Yunmin; Chen, Bing

2018-03-01

Material composition, hardness and wear properties of the throw-out plate improved are analysed on a road milling machine. At the same time, analyse the tissue and performance of Fe based alloy named Fe60 cladding layer using the plasma surfacing method. And the original and improved throw-out plates are analysed throwing material effect by the dynamic analysis. Then the throw-out plate samples are verified. The results show that Fe60 powder is selected as surface strengthening material. By the improved structure, the hardness of the throw-out plate increases from 14.6HRC to 57.5HRC, and the wear resistance increases from 0.452g-1 to 16.393g-1. At the same time, it increases from 3263 to 3433 to fall into the collecting material number of milling machine. It provides important guidance for structure design and process design of the milling machine throw-out plate.

Interactive cutting path analysis programs

NASA Technical Reports Server (NTRS)

Weiner, J. M.; Williams, D. S.; Colley, S. R.

1975-01-01

The operation of numerically controlled machine tools is interactively simulated. Four programs were developed to graphically display the cutting paths for a Monarch lathe, Cintimatic mill, Strippit sheet metal punch, and the wiring path for a Standard wire wrap machine. These programs are run on a IMLAC PDS-ID graphic display system under the DOS-3 disk operating system. The cutting path analysis programs accept input via both paper tape and disk file.

Experimental Study in Taguchi Method on Surface Quality Predication of HSM

NASA Astrophysics Data System (ADS)

Ji, Yan; Li, Yueen

2018-05-01

Based on the study of ball milling mechanism and machining surface formation mechanism, the formation of high speed ball-end milling surface is a time-varying and cumulative Thermos-mechanical coupling process. The nature of this problem is that the uneven stress field and temperature field affect the machined surface Process, the performance of the processing parameters in the processing interaction in the elastic-plastic materials produced by the elastic recovery and plastic deformation. The surface quality of machining surface is characterized by multivariable nonlinear system. It is still an indispensable and effective method to study the surface quality of high speed ball milling by experiments.

2. GENERAL VIEW OF HYDRAULIC 48' BORING MILL. Manufactured by ...

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

2. GENERAL VIEW OF HYDRAULIC 48' BORING MILL. Manufactured by Simmons Machine Tool Corporation, Albany, New York, and Betts Company, a division of Niles Tool Company, Hamilton, Ohio. - Juniata Shops, Erecting Shop & Machine Shop, East of Fourth Avenue, between Fourth & Fifth Streets, Altoona, Blair County, PA

22. INTERIOR VIEW OF THE MACHINE SHOP LOOKING NORTH. FROM ...

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

22. INTERIOR VIEW OF THE MACHINE SHOP LOOKING NORTH. FROM LEFT TO RIGHT, NORTH END OF THE LONG LATHE, WOOD STOVE WITH A BRICK HEARTH FLOOR, FAR BACK LEFT CORNER IS THE MAIN CLUTCH FOR THE MILL POWER SHAFTS, SHAFT LATHE, SMALL PLANER, BORING MACHINE WITH IONIC COLUMN DETAIL., AND THE ENTRANCE TO THE ELECTRICAL MOTOR ROOM. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

Confessions of a robot lobotomist

NASA Technical Reports Server (NTRS)

Gottshall, R. Marc

1994-01-01

Since its inception, numerically controlled (NC) machining methods have been used throughout the aerospace industry to mill, drill, and turn complex shapes by sequentially stepping through motion programs. However, the recent demand for more precision, faster feeds, exotic sensors, and branching execution have existing computer numerical control (CNC) and distributed numerical control (DNC) systems running at maximum controller capacity. Typical disadvantages of current CNC's include fixed memory capacities, limited communication ports, and the use of multiple control languages. The need to tailor CNC's to meet specific applications, whether it be expanded memory, additional communications, or integrated vision, often requires replacing the original controller supplied with the commercial machine tool with a more powerful and capable system. This paper briefly describes the process and equipment requirements for new controllers and their evolutionary implementation in an aerospace environment. The process of controller retrofit with currently available machines is examined, along with several case studies and their computational and architectural implications.

PLANING MILL, FIRST FLOOR INTERIOR, LOOKING WEST. A WHEEL BORING ...

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

PLANING MILL, FIRST FLOOR INTERIOR, LOOKING WEST. A WHEEL BORING MACHINE AND SUPERVISOR’S OFFICE ARE VISIBLE. - Southern Pacific, Sacramento Shops, Planing Mill, 111 I Street, Sacramento, Sacramento County, CA

"Grinding" cavities in polyurethane foam

NASA Technical Reports Server (NTRS)

Brower, J. R.; Davey, R. E.; Dixon, W. F.; Robb, P. H.; Zebus, P. P.

1980-01-01

Grinding tool installed on conventional milling machine cuts precise cavities in foam blocks. Method is well suited for prototype or midsize production runs and can be adapted to computer control for mass production. Method saves time and materials compared to bonding or hot wire techniques.

Multi-category micro-milling tool wear monitoring with continuous hidden Markov models

NASA Astrophysics Data System (ADS)

Zhu, Kunpeng; Wong, Yoke San; Hong, Geok Soon

2009-02-01

In-process monitoring of tool conditions is important in micro-machining due to the high precision requirement and high tool wear rate. Tool condition monitoring in micro-machining poses new challenges compared to conventional machining. In this paper, a multi-category classification approach is proposed for tool flank wear state identification in micro-milling. Continuous Hidden Markov models (HMMs) are adapted for modeling of the tool wear process in micro-milling, and estimation of the tool wear state given the cutting force features. For a noise-robust approach, the HMM outputs are connected via a medium filter to minimize the tool state before entry into the next state due to high noise level. A detailed study on the selection of HMM structures for tool condition monitoring (TCM) is presented. Case studies on the tool state estimation in the micro-milling of pure copper and steel demonstrate the effectiveness and potential of these methods.

A new optimization tool path planning for 3-axis end milling of free-form surfaces based on efficient machining intervals

NASA Astrophysics Data System (ADS)

Vu, Duy-Duc; Monies, Frédéric; Rubio, Walter

2018-05-01

A large number of studies, based on 3-axis end milling of free-form surfaces, seek to optimize tool path planning. Approaches try to optimize the machining time by reducing the total tool path length while respecting the criterion of the maximum scallop height. Theoretically, the tool path trajectories that remove the most material follow the directions in which the machined width is the largest. The free-form surface is often considered as a single machining area. Therefore, the optimization on the entire surface is limited. Indeed, it is difficult to define tool trajectories with optimal feed directions which generate largest machined widths. Another limiting point of previous approaches for effectively reduce machining time is the inadequate choice of the tool. Researchers use generally a spherical tool on the entire surface. However, the gains proposed by these different methods developed with these tools lead to relatively small time savings. Therefore, this study proposes a new method, using toroidal milling tools, for generating toolpaths in different regions on the machining surface. The surface is divided into several regions based on machining intervals. These intervals ensure that the effective radius of the tool, at each cutter-contact points on the surface, is always greater than the radius of the tool in an optimized feed direction. A parallel plane strategy is then used on the sub-surfaces with an optimal specific feed direction for each sub-surface. This method allows one to mill the entire surface with efficiency greater than with the use of a spherical tool. The proposed method is calculated and modeled using Maple software to find optimal regions and feed directions in each region. This new method is tested on a free-form surface. A comparison is made with a spherical cutter to show the significant gains obtained with a toroidal milling cutter. Comparisons with CAM software and experimental validations are also done. The results show the efficiency of the method.

Vertical marginal gap evaluation of conventional cast and computer numeric controlled-milled titanium full-arch implant-supported frameworks.

PubMed

Alfadda, Sara A

2014-01-01

To use a novel approach to measure the amount of vertical marginal gap in computer numeric controlled (CNC)-milled titanium frameworks and conventional cast frameworks. Ten cast frameworks were fabricated on the mandibular master casts of 10 patients. Then, 10 CNC-milled titanium frameworks were fabricated by laser scanning the cast frameworks. The vertical marginal gap was measured and analyzed using the Contura-G2 coordinate measuring machine and special computer software. The CNC-milled titanium frameworks showed an overall reduced mean vertical gap compared with the cast frameworks in all five analogs. This difference was highly statistically significant in the distal analogs. The largest mean gap in the cast framework was recorded in the most distal analogs, and the least amount was in the middle analog. Neither of the two types of frameworks provided a completely gap-free superstructure. The CNCmilled titanium frameworks showed a significantly smaller vertical marginal gap than the cast frameworks.

Three-dimensional tool radius compensation for multi-axis peripheral milling

NASA Astrophysics Data System (ADS)

Chen, Youdong; Wang, Tianmiao

2013-05-01

Few function about 3D tool radius compensation is applied to generating executable motion control commands in the existing computer numerical control (CNC) systems. Once the tool radius is changed, especially in the case of tool size changing with tool wear in machining, a new NC program has to be recreated. A generic 3D tool radius compensation method for multi-axis peripheral milling in CNC systems is presented. The offset path is calculated by offsetting the tool path along the direction of the offset vector with a given distance. The offset vector is perpendicular to both the tangent vector of the tool path and the orientation vector of the tool axis relative to the workpiece. The orientation vector equations of the tool axis relative to the workpiece are obtained through homogeneous coordinate transformation matrix and forward kinematics of generalized kinematics model of multi-axis machine tools. To avoid cutting into the corner formed by the two adjacent tool paths, the coordinates of offset path at the intersection point have been calculated according to the transition type that is determined by the angle between the two tool path tangent vectors at the corner. Through the verification by the solid cutting simulation software VERICUT® with different tool radiuses on a table-tilting type five-axis machine tool, and by the real machining experiment of machining a soup spoon on a five-axis machine tool with the developed CNC system, the effectiveness of the proposed 3D tool radius compensation method is confirmed. The proposed compensation method can be suitable for all kinds of three- to five-axis machine tools as a general form.

Experimental Investigation of Minimum Quantity Lubrication in Meso-scale Milling with Varying Tool Diameter

NASA Astrophysics Data System (ADS)

Yusof, M. Q. M.; Harun, H. N. S. B.; Bahar, R.

2018-01-01

Minimum quantity lubrication (MQL) is a method that uses a very small amount of liquid to reduce friction between cutting tool and work piece during machining. The implementation of MQL machining has become a viable alternative to flood cooling machining and dry machining. The overall performance has been evaluated during meso-scale milling of mild steel using different diameter milling cutters. Experiments have been conducted under two different lubrication condition: dry and MQL with variable cutting parameters. The tool wear and its surface roughness, machined surfaces microstructure and surface roughness were observed for both conditions. It was found from the results that MQL produced better results compared to dry machining. The 0.5 mm tool has been selected as the most optimum tool diameter to be used with the lowest surface roughness as well as the least flank wear generation. For the workpiece, it was observed that the cutting temperature possesses crucial effect on the microstructure and the surface roughness of the machined surface and bigger diameter tool actually resulted in higher surface roughness. The poor conductivity of the cutting tool may be one of reasons behind.

Un formalisme de systemes a sauts pour la recirculation optimale des casses dans une machine a papier

NASA Astrophysics Data System (ADS)

Khanbaghi, Maryam

Increasing closure of white water circuits is making mill productivity and quality of paper produced increasingly affected by the occurrence of paper breaks. In this thesis the main objective is the development of white water and broke recirculation policies. The thesis consists of three main parts, respectively corresponding to the synthesis of a statistical model of paper breaks in a paper mill, the basic mathematical setup for the formulation of white water and broke recirculation policies in the mill as a jump linear quadratic regulation problem, and finally the tuning of the control law based on first passage-time theory, and its extension to the case of control sensitive paper break rates. More specifically, in the first part a statistical model of paper machine breaks is developed. We start from the hypothesis that the breaks process is a Markov chain with three states: the first state is the operational one, while the two others are associated with the general types of paper-breaks that can take place in the mill (wet breaks and dry breaks). The Markovian hypothesis is empirically validated. We also establish how paper-break rates are correlated with machine speed and broke recirculation ratio. Subsequently, we show how the obtained Markov chain model of paper-breaks can be used to formulate a machine operating speed parameter optimization problem. In the second part, upon recognizing that paper breaks can be modelled as a Markov chain type of process which, when interacting with the continuous mill dynamics, yields a jump Markov model, jump linear theory is proposed as a means of constructing white water and broke recirculation strategies which minimize process variability. Reduced process variability comes at the expense of relatively large swings in white water and broke tanks level. Since the linear design does not specifically account for constraints on the state-space, under the resulting law, damaging events of tank overflow or emptiness can occur. A heuristic simulation-based approach is proposed to choose the performance measure design parameters to keep the mean time between incidents of fluid in broke and white water tanks either overflowing, or reaching dangerously low levels, sufficiently long. In the third part, a methodology, mainly founded on the first passage-time theory of stochastic processes, is proposed to choose the performance measure design parameters to limit process variability while accounting for the possibility of undesirable tank overflows or tank emptiness. The heart of the approach is an approximation technique for evaluating mean first passage-times of the controlled tanks levels. This technique appears to have an applicability which largely exceeds the problem area it was designed for. Furthermore, the introduction of control sensitive break rates and the analysis of the ensuing control problem are presented. This is to account for the experimentally observed increase in breaks concomitant with flow rate variability.

Investigation of roughing machining simulation by using visual basic programming in NX CAM system

NASA Astrophysics Data System (ADS)

Hafiz Mohamad, Mohamad; Nafis Osman Zahid, Muhammed

2018-03-01

This paper outlines a simulation study to investigate the characteristic of roughing machining simulation in 4th axis milling processes by utilizing visual basic programming in NX CAM systems. The selection and optimization of cutting orientation in rough milling operation is critical in 4th axis machining. The main purpose of roughing operation is to approximately shape the machined parts into finished form by removing the bulk of material from workpieces. In this paper, the simulations are executed by manipulating a set of different cutting orientation to generate estimated volume removed from the machine parts. The cutting orientation with high volume removal is denoted as an optimum value and chosen to execute a roughing operation. In order to run the simulation, customized software is developed to assist the routines. Operations build-up instructions in NX CAM interface are translated into programming codes via advanced tool available in the Visual Basic Studio. The codes is customized and equipped with decision making tools to run and control the simulations. It permits the integration with any independent program files to execute specific operations. This paper aims to discuss about the simulation program and identifies optimum cutting orientations for roughing processes. The output of this study will broaden up the simulation routines performed in NX CAM systems.

Milling Machine Operator: Instructor's Guide for an Adult Course.

ERIC Educational Resources Information Center

New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

The instructor's guide is for a course expected to help meet the need for trained operators in metalworking. Students successfully completing the course will be qualified for an entry-level job as a milling machine operator. The course is suitable for use in adult education programs of school districts, or in manpower development and training…

High-precision processing and detection of the high-caliber off-axis aspheric mirror

NASA Astrophysics Data System (ADS)

Dai, Chen; Li, Ang; Xu, Lingdi; Zhang, Yingjie

2017-10-01

To achieve the efficient, controllable, digital processing and high-precision detection of the high-caliber off-axis aspheric mirror, meeting the high-level development needs of the modern high-resolution, large field of space optical remote sensing camera, we carried out the research on high precision machining and testing technology of off-axis aspheric mirror. First, we forming the off-axis aspheric sample with diameter of 574mm × 302mm by milling it with milling machine, and then the intelligent robot equipment was used for off-axis aspheric high precision polishing. Surface detection of the sample will be proceed with the off-axis aspheric contact contour detection technology and offaxis non-spherical surface interference detection technology after its fine polishing using ion beam equipment. The final surface accuracy RMS is 12nm.

Laser milling of martensitic stainless steels using spiral trajectories

NASA Astrophysics Data System (ADS)

Romoli, L.; Tantussi, F.; Fuso, F.

2017-04-01

A laser beam with sub-picosecond pulse duration was driven in spiral trajectories to perform micro-milling of martensitic stainless steel. The geometry of the machined micro-grooves channels was investigated by a specifically conceived Scanning Probe Microscopy instrument and linked to laser parameters by using an experimental approach combining the beam energy distribution profile and the absorption phenomena in the material. Preliminary analysis shows that, despite the numerous parameters involved in the process, layer removal obtained by spiral trajectories, varying the radial overlap, allows for a controllable depth of cut combined to a flattening effect of surface roughness. Combining the developed machining strategy to a feed motion of the work stage, could represent a method to obtain three-dimensional structures with a resolution of few microns, with an areal roughness Sa below 100 nm.

Angular approach combined to mechanical model for tool breakage detection by eddy current sensors

NASA Astrophysics Data System (ADS)

Ritou, M.; Garnier, S.; Furet, B.; Hascoet, J. Y.

2014-02-01

The paper presents a new complete approach for Tool Condition Monitoring (TCM) in milling. The aim is the early detection of small damages so that catastrophic tool failures are prevented. A versatile in-process monitoring system is introduced for reliability concerns. The tool condition is determined by estimates of the radial eccentricity of the teeth. An adequate criterion is proposed combining mechanical model of milling and angular approach.Then, a new solution is proposed for the estimate of cutting force using eddy current sensors implemented close to spindle nose. Signals are analysed in the angular domain, notably by synchronous averaging technique. Phase shifts induced by changes of machining direction are compensated. Results are compared with cutting forces measured with a dynamometer table.The proposed method is implemented in an industrial case of pocket machining operation. One of the cutting edges has been slightly damaged during the machining, as shown by a direct measurement of the tool. A control chart is established with the estimates of cutter eccentricity obtained during the machining from the eddy current sensors signals. Efficiency and reliability of the method is demonstrated by a successful detection of the damage.

Diagnosis of the Computer-Controlled Milling Machine, Definition of the Working Errors and Input Corrections on the Basis of Mathematical Model

NASA Astrophysics Data System (ADS)

Starikov, A. I.; Nekrasov, R. Yu; Teploukhov, O. J.; Soloviev, I. V.; Narikov, K. A.

2016-10-01

Manufactures, machinery and equipment improve of constructively as science advances and technology, and requirements are improving of quality and longevity. That is, the requirements for surface quality and precision manufacturing, oil and gas equipment parts are constantly increasing. Production of oil and gas engineering products on modern machine tools with computer numerical control - is a complex synthesis of technical and electrical equipment parts, as well as the processing procedure. Technical machine part wears during operation and in the electrical part are accumulated mathematical errors. Thus, the above-mentioned disadvantages of any of the following parts of metalworking equipment affect the manufacturing process of products in general, and as a result lead to the flaw.

In vitro evaluation of marginal discrepancy of monolithic zirconia restorations fabricated with different CAD-CAM systems.

PubMed

Hamza, Tamer A; Sherif, Rana M

2017-06-01

Dental laboratories use different computer-aided design and computer-aided manufacturing (CAD-CAM) systems to fabricate fixed prostheses; however, limited evidence is available concerning which system provides the best marginal discrepancy. The purpose of this in vitro study was to evaluate the marginal fit of 5 different monolithic zirconia restorations milled with different CAD-CAM systems. Thirty monolithic zirconia crowns were fabricated on a custom-designed stainless steel die and were divided into 5 groups according to the type of monolithic zirconia crown and the CAD-CAM system used: group TZ, milled with an MCXL milling machine; group CZ, translucent zirconia milled with a motion milling machine; group ZZ, zirconia milled with a dental milling unit; group PZ, translucent zirconia milled with a zirconia milling unit; and group BZ, solid zirconia milled using an S1 VHF milling machine. The marginal fit was measured with a binocular microscope at an original magnification of ×100. The results were tabulated and statistically analyzed with 1-way ANOVA and post hoc surface range test, and pairwise multiple comparisons were made using Bonferroni correction (α=.05). The type of CAD-CAM used affected the marginal fit of the monolithic restoration. The mean (±SD) highest marginal discrepancy was recorded in group TZI at 39.3 ±2.3 μm, while the least mean marginal discrepancy was recorded in group IZ (22.8 ±8.9 μm). The Bonferroni post hoc test showed that group TZI was significantly different from all other groups tested (P<.05). Within the limitation of this in vitro study, all tested CAD-CAM systems produced monolithic zirconia restorations with clinically acceptable marginal discrepancies; however, the CAD-CAM system with the 5-axis milling unit produced the best marginal fit. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

PLANING MILL, FIRST FLOOR INTERIOR, LOOKING SOUTH. THE LARGE DEVICE ...

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

PLANING MILL, FIRST FLOOR INTERIOR, LOOKING SOUTH. THE LARGE DEVICE IS A WHEEL BORING MACHINE USED DURING THE TIME THIS AREA WAS A WHEEL SHOP. - Southern Pacific, Sacramento Shops, Planing Mill, 111 I Street, Sacramento, Sacramento County, CA

A novel toolpath force prediction algorithm using CAM volumetric data for optimizing robotic arthroplasty.

PubMed

Kianmajd, Babak; Carter, David; Soshi, Masakazu

2016-10-01

Robotic total hip arthroplasty is a procedure in which milling operations are performed on the femur to remove material for the insertion of a prosthetic implant. The robot performs the milling operation by following a sequential list of tool motions, also known as a toolpath, generated by a computer-aided manufacturing (CAM) software. The purpose of this paper is to explain a new toolpath force prediction algorithm that predicts cutting forces, which results in improving the quality and safety of surgical systems. With a custom macro developed in the CAM system's native application programming interface, cutting contact patch volume was extracted from CAM simulations. A time domain cutting force model was then developed through the use of a cutting force prediction algorithm. The second portion validated the algorithm by machining a hip canal in simulated bone using a CNC machine. Average cutting forces were measured during machining using a dynamometer and compared to the values predicted from CAM simulation data using the proposed method. The results showed the predicted forces matched the measured forces in both magnitude and overall pattern shape. However, due to inconsistent motion control, the time duration of the forces was slightly distorted. Nevertheless, the algorithm effectively predicted the forces throughout an entire hip canal procedure. This method provides a fast and easy technique for predicting cutting forces during orthopedic milling by utilizing data within a CAM software.

An integrated condition-monitoring method for a milling process using reduced decomposition features

NASA Astrophysics Data System (ADS)

Liu, Jie; Wu, Bo; Wang, Yan; Hu, Youmin

2017-08-01

Complex and non-stationary cutting chatter affects productivity and quality in the milling process. Developing an effective condition-monitoring approach is critical to accurately identify cutting chatter. In this paper, an integrated condition-monitoring method is proposed, where reduced features are used to efficiently recognize and classify machine states in the milling process. In the proposed method, vibration signals are decomposed into multiple modes with variational mode decomposition, and Shannon power spectral entropy is calculated to extract features from the decomposed signals. Principal component analysis is adopted to reduce feature size and computational cost. With the extracted feature information, the probabilistic neural network model is used to recognize and classify the machine states, including stable, transition, and chatter states. Experimental studies are conducted, and results show that the proposed method can effectively detect cutting chatter during different milling operation conditions. This monitoring method is also efficient enough to satisfy fast machine state recognition and classification.

Mathematical modelling and numerical simulation of forces in milling process

NASA Astrophysics Data System (ADS)

Turai, Bhanu Murthy; Satish, Cherukuvada; Prakash Marimuthu, K.

2018-04-01

Machining of the material by milling induces forces, which act on the work piece material, tool and which in turn act on the machining tool. The forces involved in milling process can be quantified, mathematical models help to predict these forces. A lot of research has been carried out in this area in the past few decades. The current research aims at developing a mathematical model to predict forces at different levels which arise machining of Aluminium6061 alloy. Finite element analysis was used to develop a FE model to predict the cutting forces. Simulation was done for varying cutting conditions. Different experiments was designed using Taguchi method. A L9 orthogonal array was designed and the output was measure for the different experiments. The same was used to develop the mathematical model.

GENERAL VIEW OF WESTERN PART OF PLANT INCLUDING (LEFT TO ...

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

GENERAL VIEW OF WESTERN PART OF PLANT INCLUDING (LEFT TO RIGHT) BETHLEHEM RAIL MILL, GENERAL OFFICE BUILDING, MACHINE SHOP, BAR MILL, BLOOMING MILL & OPEN HEARTH PLANT. - Pittsburgh Steel Company, Monessen Works, Open Hearth Plant, Donner Avenue, Monessen, Westmoreland County, PA

1. EAGLE MILL EXTERIOR FROM NORTHWEST, c. 1907. SHOWS INITIAL ...

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

1. EAGLE MILL EXTERIOR FROM NORTHWEST, c. 1907. SHOWS INITIAL MILL CONFIGURATION WITH FULLY EXPOSED CRUDE ORE BIN CONCRETE RETAINING WALL, SINGLE (SOUTH) CRUDE ORE BIN, AND EXPOSED CRUSHER HOUSE. NOTE THE LACK OF MACHINE SHOP OR SNOW SHEDS. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

A Performance Comparison Study of Uncoated and TiAlN Coated Carbide End Mill on Machining of the Al-35Zn Alloy

NASA Astrophysics Data System (ADS)

Bayraktar, S.; Hekimoglu, A. P.; Turgut, Y.; Haciosmanoglu, M.

2018-01-01

In this study, Al-35Zn alloy was produced by permanent mold casting. To investigate the cutting performance of uncoated and TiAlN coated carbide end mills on this alloy, a series of tests were carried out in the CNC vertical machining center at a constant cutting speed, feed rate and depth of cut. The results obtained from the tests showed that uncoated carbide end mill have lower cutting force and surface roughness than TiAlN coated carbide end mill. These observations are discussed in terms of the alloys properties, cutting tool surfaces, and friction and wear behavior between the cutting tool and the material.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

PubMed Central

García Nieto, Paulino José; García-Gonzalo, Esperanza; Ordóñez Galán, Celestino; Bernardo Sánchez, Antonio

2016-01-01

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC–MARS-based model was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc. Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC–MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed. PMID:28787882

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data.

PubMed

García Nieto, Paulino José; García-Gonzalo, Esperanza; Ordóñez Galán, Celestino; Bernardo Sánchez, Antonio

2016-01-28

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC-MARS-based model was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc . Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC-MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed.

Comparative Investigation on Tool Wear during End Milling of AISI H13 Steel with Different Tool Path Strategies

NASA Astrophysics Data System (ADS)

Adesta, Erry Yulian T.; Riza, Muhammad; Avicena

2018-03-01

Tool wear prediction plays a significant role in machining industry for proper planning and control machining parameters and optimization of cutting conditions. This paper aims to investigate the effect of tool path strategies that are contour-in and zigzag tool path strategies applied on tool wear during pocket milling process. The experiments were carried out on CNC vertical machining centre by involving PVD coated carbide inserts. Cutting speed, feed rate and depth of cut were set to vary. In an experiment with three factors at three levels, Response Surface Method (RSM) design of experiment with a standard called Central Composite Design (CCD) was employed. Results obtained indicate that tool wear increases significantly at higher range of feed per tooth compared to cutting speed and depth of cut. This result of this experimental work is then proven statistically by developing empirical model. The prediction model for the response variable of tool wear for contour-in strategy developed in this research shows a good agreement with experimental work.

Processing mill scale study data on a type 650 electronic machine.

Treesearch

Floyd A. Johnson

1956-01-01

During April 1956, about 20,000 boards from 210 white fir and 290 western hemlock logs were measured at a lumber mill in western Washington. A magnetic drum, data-processing machine (type 650) was then used to calculate board-feet volumes by lumber grade for each log, and average board-foot volumes by lumber grade for each log diameter-class within log grades and...

Feel the Force of Cogs, Pulleys and Water Power

ERIC Educational Resources Information Center

Pugh, Julie

2016-01-01

Quarry Bank Mill in Cheshire was built in 1784 and was one of the first water-powered cotton mills of the Industrial Revolution. While the machines are now powered by electricity, the water wheel still turns and the machines run. Linking the two are cogs, shafts and belts, so it is possible to see how the power of the river was captured and then…

Impact of high-pressure coolant supply on chip formation in milling

NASA Astrophysics Data System (ADS)

Klocke, F.; Döbbeler, B.; Lakner, T.

2017-10-01

Machining of titanium alloys is considered as difficult, because of their high temperature strength, low thermal conductivity and low E-modulus, which contributes to high mechanical loads and high temperatures in the contact zone between tool and workpiece. The generated heat in the cutting zone can be dissipated only in a low extent. When cutting steel materials, up to 75% of the process heat is transported away by the chips, contrary to only 25% when machining titanium alloys. As a result, the cutting tool heats up, which leads to high tool wear. Therefore, machining of titanium alloys is only possible with relatively low cutting speeds. This leads to low levels of productivity for milling processes with titanium alloys. One way to increase productivity is to use more cutting edges in tools with the same diameter. However, the limiting factor of adding more cutting edges to a milling tool is the minimum size of the chip spaces, which are sufficient for a stable chip evacuation. This paper presents experimental results on the chip formation and chip size influenced by high-pressure coolant supply, which can lead to smaller chips and to smaller sizes of the chip spaces, respectively. Both influences, the pressure of the supplied coolant and the volumetric flow rate were individually examined. Alpha-beta annealed titanium TiAl6V4 was examined in relation to the reference material quenched and tempered steel 42CrMo4+QT (AISI 4140+QT). The work shows that with proper chip control due to high-pressure coolant supply in milling, the number of cutting edges on the same diameter tool can be increased, which leads to improved productivity.

A new milling machine for computer-aided, in-office restorations.

PubMed

Kurbad, Andreas

Chairside computer-aided design/computer-aided manufacturing (CAD/CAM) technology requires an effective technical basis to obtain dental restorations with optimal marginal accuracy, esthetics, and longevity in as short a timeframe as possible. This article describes a compact, 5-axis milling machine based on an innovative milling technology (5XT - five-axis turn-milling technique), which is capable of achieving high-precision milling results within a very short processing time. Furthermore, the device's compact dimensioning and state-of-the-art mode of operation facilitate its use in the dental office. This model is also an option to be considered for use in smaller dental laboratories, especially as the open input format enables it to be quickly and simply integrated into digital processing systems already in use. The possibility of using ceramic and polymer materials with varying properties enables the manufacture of restorations covering all conceivable indications in the field of fixed dental prosthetics.

Identification of Technological Parameters of Ni-Alloys When Machining by Monolithic Ceramic Milling Tool

NASA Astrophysics Data System (ADS)

Czán, Andrej; Kubala, Ondrej; Danis, Igor; Czánová, Tatiana; Holubják, Jozef; Mikloš, Matej

2017-12-01

The ever-increasing production and the usage of hard-to-machine progressive materials are the main cause of continual finding of new ways and methods of machining. One of these ways is the ceramic milling tool, which combines the pros of conventional ceramic cutting materials and pros of conventional coating steel-based insert. These properties allow to improve cutting conditions and so increase the productivity with preserved quality known from conventional tools usage. In this paper, there is made the identification of properties and possibilities of this tool when machining of hard-to-machine materials such as nickel alloys using in airplanes engines. This article is focused on the analysis and evaluation ordinary technological parameters and surface quality, mainly roughness of surface and quality of machined surface and tool wearing.

Machinability evaluation of titanium alloys (Part 2)--Analyses of cutting force and spindle motor current.

PubMed

Kikuchi, Masafumi; Okuno, Osamu

2004-12-01

To establish a method of determining the machinability of dental materials for CAD/CAM systems, the machinability of titanium, two titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb), and free-cutting brass was evaluated through cutting force and spindle motor current. The metals were slotted using a milling machine and square end mills at four cutting conditions. Both the static and dynamic components of the cutting force represented well the machinability of the metals tested: the machinability of Ti-6Al-4V and Ti-6Al-7Nb was worse than that of titanium, while that of free-cutting brass was better. On the other hand, the results indicated that the spindle motor current was not sensitive enough to detect the material difference among the titanium and its alloys.

11. BALD MOUNTAIN MILL, EXTERIOR FROM NORTHEAST, c. 194059. ROASTER ...

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

11. BALD MOUNTAIN MILL, EXTERIOR FROM NORTHEAST, c. 1940-59. ROASTER AND OTHER UNOXIDIZED ORE CIRCUIT ADDITIONS PRESENT, ALONG WITH SECONDARY THICKENER No. 7 AND ADDITIONS TO MACHINE SHOP. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

78 FR 73886 - Schweitzer-Mauduit International, Inc., Paper Machine #21, Ancram, New York; Schweitzer-Mauduit...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-09

...., Columbia Mill, Lee, Massachusetts; Amended Certification Regarding Eligibility To Apply for Worker... revealed that workers of Schweitzer-Mauduit International, Inc., Columbia Mill, Lee, Massachusetts are... working at Schweitzer-Mauduit International, Inc., Columbia Mill, Lee, Massachusetts (TA-W-82,718A). The...

Machinability of CAD-CAM materials.

PubMed

Chavali, Ramakiran; Nejat, Amir H; Lawson, Nathaniel C

2017-08-01

Although new materials are available for computer-aided design and computer-aided manufacturing (CAD-CAM) fabrication, limited information is available regarding their machinability. The depth of penetration of a milling tool into a material during a timed milling cycle may indicate its machinability. The purpose of this in vitro study was to compare the tool penetration rate for 2 polymer-containing CAD-CAM materials (Lava Ultimate and Enamic) and 2 ceramic-based CAD-CAM materials (e.max CAD and Celtra Duo). The materials were sectioned into 4-mm-thick specimens (n=5/material) and polished with 320-grit SiC paper. Each specimen was loaded into a custom milling apparatus. The apparatus pushed the specimens against a milling tool (E4D Tapered 2016000) rotating at 40 000 RPM with a constant force of 0.98 N. After a 6-minute timed milling cycle, the length of each milling cut was measured with image analysis software under a digital light microscope. Representative specimens and milling tools were examined with scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy. The penetration rate of Lava Ultimate (3.21 ±0.46 mm/min) and Enamic (2.53 ±0.57 mm/min) was significantly greater than that of e.max CAD (1.12 ±0.32 mm/min) or Celtra Duo (0.80 ±0.21 mm/min) materials. SEM observations showed little tool damage, regardless of material type. Residual material was found on the tools used with polymer-containing materials, and wear of the embedding medium was seen on the tools used with the ceramic-based materials. Edge chipping was noted on cuts made in the ceramic-based materials. Lava Ultimate and Enamic have greater machinability and less edge chipping than e.max CAD and Celtra Duo. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Depth indicator and stop aid machining to precise tolerances

NASA Technical Reports Server (NTRS)

Laverty, J. L.

1966-01-01

Attachment for machine tools provides a visual indication of the depth of cut and a positive stop to prevent overcutting. This attachment is used with drill presses, vertical milling machines, and jig borers.

19. General view showing garneting machine number eight on right, ...

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

19. General view showing garneting machine number eight on right, and garneting machines numbers four through seven on left in background - Norfolk Manufacturing Company Cotton Mill, 90 Milton Street, Dedham, Norfolk County, MA

Minimization of energy and surface roughness of the products machined by milling

NASA Astrophysics Data System (ADS)

Belloufi, A.; Abdelkrim, M.; Bouakba, M.; Rezgui, I.

2017-08-01

Metal cutting represents a large portion in the manufacturing industries, which makes this process the largest consumer of energy. Energy consumption is an indirect source of carbon footprint, we know that CO2 emissions come from the production of energy. Therefore high energy consumption requires a large production, which leads to high cost and a large amount of CO2 emissions. At this day, a lot of researches done on the Metal cutting, but the environmental problems of the processes are rarely discussed. The right selection of cutting parameters is an effective method to reduce energy consumption because of the direct relationship between energy consumption and cutting parameters in machining processes. Therefore, one of the objectives of this research is to propose an optimization strategy suitable for machining processes (milling) to achieve the optimum cutting conditions based on the criterion of the energy consumed during the milling. In this paper the problem of energy consumed in milling is solved by an optimization method chosen. The optimization is done according to the different requirements in the process of roughing and finishing under various technological constraints.

View north of west gallery of inside machine shop 36; ...

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

View north of west gallery of inside machine shop 36; the gallery housed turret, engine and toolroom lathes, small milling machines and drill presses used for machining small parts. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure Shop, League Island, Philadelphia, Philadelphia County, PA

Application of dynamic milling in stainless steel processing

NASA Astrophysics Data System (ADS)

Shan, Wenju

2017-09-01

This paper mainly introduces the method of parameter setting for NC programming of stainless steel parts by dynamic milling. Stainless steel is of high plasticity and toughness, serious hard working, large cutting force, high temperature in cutting area and easy wear of tool. It is difficult to process material. Dynamic motion technology is the newest NC programming technology of Mastercam software. It is an advanced machining idea. The tool path generated by the dynamic motion technology is more smooth, more efficient and more stable in the machining process. Dynamic motion technology is very suitable for cutting hard machining materials.

Smart Cutting Tools and Smart Machining: Development Approaches, and Their Implementation and Application Perspectives

NASA Astrophysics Data System (ADS)

Cheng, Kai; Niu, Zhi-Chao; Wang, Robin C.; Rakowski, Richard; Bateman, Richard

2017-09-01

Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative design concepts and, in particular, the development of four types of smart cutting tools, including a force-based smart cutting tool, a temperature-based internally-cooled cutting tool, a fast tool servo (FTS) and smart collets for ultraprecision and micro manufacturing purposes. Implementation and application perspectives of these smart cutting tools are explored and discussed particularly for smart machining against a number of industrial application requirements. They are contamination-free machining, machining of tool-wear-prone Si-based infra-red devices and medical applications, high speed micro milling and micro drilling, etc. Furthermore, implementation techniques are presented focusing on: (a) plug-and-produce design principle and the associated smart control algorithms, (b) piezoelectric film and surface acoustic wave transducers to measure cutting forces in process, (c) critical cutting temperature control in real-time machining, (d) in-process calibration through machining trials, (e) FE-based design and analysis of smart cutting tools, and (f) application exemplars on adaptive smart machining.

Feasibility investigations on multi-cutter milling process: A novel fabrication method for microreactors with multiple microchannels

NASA Astrophysics Data System (ADS)

Pan, Minqiang; Zeng, Dehuai; Tang, Yong

A novel multi-cutter milling process for multiple parallel microchannels with manifolds is proposed to address the challenge of mass manufacture as required for cost-effective commercial applications. Several slotting cutters are stacked together to form a composite tool for machining microchannels simultaneously. The feasibility of this new fabrication process is experimentally investigated under different machining conditions and reaction characteristics of methanol steam reforming for hydrogen production. The influences of cutting parameters and the composite tool on the microchannel qualities and burr formation are analyzed. Experimental results indicate that larger cutting speed, smaller feed rate and cutting depth are in favor of obtaining relatively good microchannel qualities and small burrs. Of all the cutting parameters considered in these experiments, 94.2 m min -1 cutting speed, 23.5 mm min -1 feed rate and 0.5 mm cutting depth are found to be the optimum value. According to the comparisons of experimental results of multi-cutter milling process and estimated one of other alternative methods, it is found that multi-cutter milling process shows much shorter machining time and higher work removal rate than that of other alternative methods. Reaction characteristics of methanol steam reforming in microchannels also indicate that multi-cutter milling process is probably suitable for a commercial application.

Virtual Planning, Control, and Machining for a Modular-Based Automated Factory Operation in an Augmented Reality Environment

PubMed Central

Pai, Yun Suen; Yap, Hwa Jen; Md Dawal, Siti Zawiah; Ramesh, S.; Phoon, Sin Ye

2016-01-01

This study presents a modular-based implementation of augmented reality to provide an immersive experience in learning or teaching the planning phase, control system, and machining parameters of a fully automated work cell. The architecture of the system consists of three code modules that can operate independently or combined to create a complete system that is able to guide engineers from the layout planning phase to the prototyping of the final product. The layout planning module determines the best possible arrangement in a layout for the placement of various machines, in this case a conveyor belt for transportation, a robot arm for pick-and-place operations, and a computer numerical control milling machine to generate the final prototype. The robotic arm module simulates the pick-and-place operation offline from the conveyor belt to a computer numerical control (CNC) machine utilising collision detection and inverse kinematics. Finally, the CNC module performs virtual machining based on the Uniform Space Decomposition method and axis aligned bounding box collision detection. The conducted case study revealed that given the situation, a semi-circle shaped arrangement is desirable, whereas the pick-and-place system and the final generated G-code produced the highest deviation of 3.83 mm and 5.8 mm respectively. PMID:27271840

Virtual Planning, Control, and Machining for a Modular-Based Automated Factory Operation in an Augmented Reality Environment.

PubMed

Pai, Yun Suen; Yap, Hwa Jen; Md Dawal, Siti Zawiah; Ramesh, S; Phoon, Sin Ye

2016-06-07

This study presents a modular-based implementation of augmented reality to provide an immersive experience in learning or teaching the planning phase, control system, and machining parameters of a fully automated work cell. The architecture of the system consists of three code modules that can operate independently or combined to create a complete system that is able to guide engineers from the layout planning phase to the prototyping of the final product. The layout planning module determines the best possible arrangement in a layout for the placement of various machines, in this case a conveyor belt for transportation, a robot arm for pick-and-place operations, and a computer numerical control milling machine to generate the final prototype. The robotic arm module simulates the pick-and-place operation offline from the conveyor belt to a computer numerical control (CNC) machine utilising collision detection and inverse kinematics. Finally, the CNC module performs virtual machining based on the Uniform Space Decomposition method and axis aligned bounding box collision detection. The conducted case study revealed that given the situation, a semi-circle shaped arrangement is desirable, whereas the pick-and-place system and the final generated G-code produced the highest deviation of 3.83 mm and 5.8 mm respectively.

Virtual Planning, Control, and Machining for a Modular-Based Automated Factory Operation in an Augmented Reality Environment

NASA Astrophysics Data System (ADS)

Pai, Yun Suen; Yap, Hwa Jen; Md Dawal, Siti Zawiah; Ramesh, S.; Phoon, Sin Ye

2016-06-01

This study presents a modular-based implementation of augmented reality to provide an immersive experience in learning or teaching the planning phase, control system, and machining parameters of a fully automated work cell. The architecture of the system consists of three code modules that can operate independently or combined to create a complete system that is able to guide engineers from the layout planning phase to the prototyping of the final product. The layout planning module determines the best possible arrangement in a layout for the placement of various machines, in this case a conveyor belt for transportation, a robot arm for pick-and-place operations, and a computer numerical control milling machine to generate the final prototype. The robotic arm module simulates the pick-and-place operation offline from the conveyor belt to a computer numerical control (CNC) machine utilising collision detection and inverse kinematics. Finally, the CNC module performs virtual machining based on the Uniform Space Decomposition method and axis aligned bounding box collision detection. The conducted case study revealed that given the situation, a semi-circle shaped arrangement is desirable, whereas the pick-and-place system and the final generated G-code produced the highest deviation of 3.83 mm and 5.8 mm respectively.

29 CFR 1910.212 - General requirements for all machines.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Machinery and Machine Guarding § 1910.212...) Alligator shears. (d) Power presses. (e) Milling machines. (f) Power saws. (g) Jointers. (h) Portable power...) Anchoring fixed machinery. Machines designed for a fixed location shall be securely anchored to prevent...

29 CFR 1910.212 - General requirements for all machines.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Machinery and Machine Guarding § 1910.212...) Alligator shears. (d) Power presses. (e) Milling machines. (f) Power saws. (g) Jointers. (h) Portable power...) Anchoring fixed machinery. Machines designed for a fixed location shall be securely anchored to prevent...

29 CFR 1910.212 - General requirements for all machines.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Machinery and Machine Guarding § 1910.212...) Alligator shears. (d) Power presses. (e) Milling machines. (f) Power saws. (g) Jointers. (h) Portable power...) Anchoring fixed machinery. Machines designed for a fixed location shall be securely anchored to prevent...

Development of a Tri-Axial Cutting Force Sensor for the Milling Process

PubMed Central

Li, Yingxue; Zhao, Yulong; Fei, Jiyou; Zhao, You; Li, Xiuyuan; Gao, Yunxiang

2016-01-01

This paper presents a three-component fixed dynamometer based on a strain gauge, which reduces output errors produced by the cutting force imposed on different milling positions of the workpiece. A reformative structure of tri-layer cross beams is proposed, sensitive areas were selected, and corresponding measuring circuits were arranged to decrease the inaccuracy brought about by positional variation. To simulate the situation with a milling cutter moving on the workpiece and validate the function of reducing the output errors when the milling position changes, both static calibration and dynamic milling tests were implemented on different parts of the workpiece. Static experiment results indicate that with standard loads imposed, the maximal deviation between the measured forces and the standard inputs is 4.87%. The results of the dynamic milling test illustrate that with identical machining parameters, the differences in output variation between the developed sensor and standard dynamometer are no larger than 6.61%. Both static and dynamic experimental results demonstrate that the developed dynamometer is suitable for measuring milling force imposed on different positions of the workpiece, which shows potential applicability in machining a monitoring system. PMID:27007374

24. VIEW OF MILL FROM UPPER TAILINGS POND (NORTH). ROASTER ...

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

24. VIEW OF MILL FROM UPPER TAILINGS POND (NORTH). ROASTER ON LEFT WITH ELEVATOR/CRUSHED ORE BIN TOWER TO RIGHT. MAIN MILL BUILDING IN CENTER WITH THICKENER ADDITION TO RIGHT. MACHINE SHOP ON CRUDE ORE BIN TERRACE ABOVE ROASTER. THE LOCATION OF THE 100,000 GALLON MILL WATER TANK CAN BE SEEN AT THE CENTER RIGHT NEAR THE TOP OF THE MOUNTAIN. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

165. VIEW OF MILL FROM UPPER TAILINGS POND (NORTH). ROASTER ...

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

165. VIEW OF MILL FROM UPPER TAILINGS POND (NORTH). ROASTER ON LEFT WITH ELEVATOR/CRUSHED ORE BIN TOWER TO RIGHT. MAIN MILL BUILDING IN CENTER WITH THICKENER ADDITION TO RIGHT. MACHINE SHOP ON CRUDE ORE BIN TERRACE ABOVE ROASTER. THE LOCATION OF THE 100,000 GALLON MILL WATER TANK CAN BE SEEN AT THE CENTER RIGHT NEAR THE TOP OF THE MOUNTAIN - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

4. VIEW OF BORING MILL IN OPERATION, operator unknown (note ...

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

4. VIEW OF BORING MILL IN OPERATION, operator unknown (note console in background). - Juniata Shops, Erecting Shop & Machine Shop, East of Fourth Avenue, between Fourth & Fifth Streets, Altoona, Blair County, PA

3. VIEW OF BORING MILL IN OPERATION, operator unknown (note ...

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

3. VIEW OF BORING MILL IN OPERATION, operator unknown (note console in background). - Juniata Shops, Erecting Shop & Machine Shop, East of Fourth Avenue, between Fourth & Fifth Streets, Altoona, Blair County, PA

The relationship between milling a new silica-doped zirconia and its resistance to low-temperature degradation (LTD): a pilot study.

PubMed

Nakamura, Takashi; Usami, Hirofumi; Ohnishi, Hiroshi; Nishida, Hisataka; Tang, Xuehua; Wakabayashi, Kazumichi; Sekino, Tohru; Yatani, Hirofumi

2012-02-03

The aim of this study was to determine the machinability of new silica-doped Y-TZP by CAD/CAM and the resistance to low temperature degradation of the milled sample by comparing with a commercial HIP type Y-TZP material. The copings could be milled from silica-doped Y-TZP blocks without chipping, and there was no significant difference between the two types of Y-TZP materials in either the marginal or the inner gap between the abutment and the coping. After aging, the monoclinic content in the commercial Y-TZP copings increased from 25% before testing to 65%, while that of silica-doped Y-TZP copings slightly increased from 23% to 30%. The silica-doped Y-TZP copings did not have any significant difference in fracture load in a comparison between the control group and the aging group, while the commercial Y-TZP copings had a significantly lower fracture load for the aging group than for the control group.

New Single Piece Blast Hardware design

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

Ulrich, Andri; Steinzig, Michael Louis; Aragon, Daniel Adrian

W, Q and PF engineers and machinists designed and fabricated, on the new Mazak i300, the first Single Piece Blast Hardware (unclassified design shown) reducing fabrication and inspection time by over 50%. The first DU Single Piece is completed and will be used for Hydro Test 3680. Past hydro tests used a twopiece assembly due to a lack of equipment capable of machining the complex saddle shape in a single piece. The i300 provides turning and milling 5-axis machining on one machine. The milling head on the i300 can machine past 90 relative to the spindle axis. This makes itmore » possible to machine the complex saddle surface on a single piece. Going to a single piece eliminates tolerance problems, such as tilting and eccentricity, that typically occurred when assembling the two pieces together« less

12. Jet Lowe, Photographer, June 1979. FIRST FLOOR INTERIOR LOOKING ...

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

12. Jet Lowe, Photographer, June 1979. FIRST FLOOR INTERIOR LOOKING NORTH. SHOWING SELF-RISING FLOUR BIN AND SALEM MACHINE WORKS' WHEAT ROLLER MILLS AND FLOUR BAGGER/COMPACTOR. - Womack's Mill, Yanceyville, Caswell County, NC

Epoxy blanket protects milled part during explosive forming

NASA Technical Reports Server (NTRS)

1966-01-01

Epoxy blanket protects chemically milled or machined sections of large, complex structural parts during explosive forming. The blanket uniformly covers all exposed surfaces and fills any voids to support and protect the entire part.

Looking Northeast at Southwest End of Maintenance Shop with Milling ...

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

Looking Northeast at Southwest End of Maintenance Shop with Milling Machines, Hoist, Electrical Boxes in Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

Application of dragonfly algorithm for optimal performance analysis of process parameters in turn-mill operations- A case study

NASA Astrophysics Data System (ADS)

Vikram, K. Arun; Ratnam, Ch; Lakshmi, VVK; Kumar, A. Sunny; Ramakanth, RT

2018-02-01

Meta-heuristic multi-response optimization methods are widely in use to solve multi-objective problems to obtain Pareto optimal solutions during optimization. This work focuses on optimal multi-response evaluation of process parameters in generating responses like surface roughness (Ra), surface hardness (H) and tool vibration displacement amplitude (Vib) while performing operations like tangential and orthogonal turn-mill processes on A-axis Computer Numerical Control vertical milling center. Process parameters like tool speed, feed rate and depth of cut are considered as process parameters machined over brass material under dry condition with high speed steel end milling cutters using Taguchi design of experiments (DOE). Meta-heuristic like Dragonfly algorithm is used to optimize the multi-objectives like ‘Ra’, ‘H’ and ‘Vib’ to identify the optimal multi-response process parameters combination. Later, the results thus obtained from multi-objective dragonfly algorithm (MODA) are compared with another multi-response optimization technique Viz. Grey relational analysis (GRA).

41 CFR 50-204.5 - Machine guarding.

Code of Federal Regulations, 2011 CFR

2011-07-01

... usually require point of operation guarding: Guillotine cutters. Shears. Alligator shears. Power presses. Milling machines. Power saws. Jointers. Portable power tools. Forming rolls and calenders. (d) Revolving...

Sine-Bar Attachment For Machine Tools

NASA Technical Reports Server (NTRS)

Mann, Franklin D.

1988-01-01

Sine-bar attachment for collets, spindles, and chucks helps machinists set up quickly for precise angular cuts that require greater precision than provided by graduations of machine tools. Machinist uses attachment to index head, carriage of milling machine or lathe relative to table or turning axis of tool. Attachment accurate to 1 minute or arc depending on length of sine bar and precision of gauge blocks in setup. Attachment installs quickly and easily on almost any type of lathe or mill. Requires no special clamps or fixtures, and eliminates many trial-and-error measurements. More stable than improvised setups and not jarred out of position readily.

6. VIEW LOOKING NORTHWEST FROM THE IMAGE LEFT TO THE ...

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

6. VIEW LOOKING NORTHWEST FROM THE IMAGE LEFT TO THE IMAGE RIGHT IS THE CHARCOAL HOUSE, THE RETORT SHED IN THE BACKGROUND, THE MILL ANNEX, THE MACHINE SHOP, AND THE ELECTRIC MOTOR ROOM. THE MILL BUILDING IS IN THE BACKGROUND CENTER RIGHT AND ONE OF THE ORE DELIVERY TRESTLES EXTENDING FROM THE MILL BUILDING TO RIGHT IMAGE EDGE. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

Preparation of Mo-Re-C samples containing Mo7Re13C with the β-Mn-type structure by solid state reaction of planetary-ball-milled powder mixtures of Mo, Re and C, and their crystal structures and superconductivity

NASA Astrophysics Data System (ADS)

Oh-ishi, Katsuyoshi; Nagumo, Kenta; Tateishi, Kazuya; Takafumi, Ohnishi; Yoshikane, Kenta; Sugiyama, Machiko; Oka, Kengo; Kobayashi, Ryota

2017-01-01

Mo-Re-C compounds containing Mo7Re13C with the β-Mn structure were synthesized with high-melting-temperature metals Mo, Re, and C powders using a conventional solid state method with a planetary ball milling machine instead of the arc melting method. Use of the ball milling machine was necessary to obtain Mo7Re13C with the β-Mn structure using the solid state method. Almost single-phase Mo7Re13C with a trace of impurity were obtained using the synthesis method. By XRF and lattice parameter measurements on the samples, Fe element existed in the compound synthesized using the planetary ball milling machine with a pot and balls made of steel, though Fe element was not detected in the compound synthesized using a pot and balls made of tungsten carbide. The former compound containg the Fe atom did not show superconductivity but the latter compound without the Fe atom showed superconductivity at 6.1 K.

A Virtual Sensor for Online Fault Detection of Multitooth-Tools

PubMed Central

Bustillo, Andres; Correa, Maritza; Reñones, Anibal

2011-01-01

The installation of suitable sensors close to the tool tip on milling centres is not possible in industrial environments. It is therefore necessary to design virtual sensors for these machines to perform online fault detection in many industrial tasks. This paper presents a virtual sensor for online fault detection of multitooth tools based on a Bayesian classifier. The device that performs this task applies mathematical models that function in conjunction with physical sensors. Only two experimental variables are collected from the milling centre that performs the machining operations: the electrical power consumption of the feed drive and the time required for machining each workpiece. The task of achieving reliable signals from a milling process is especially complex when multitooth tools are used, because each kind of cutting insert in the milling centre only works on each workpiece during a certain time window. Great effort has gone into designing a robust virtual sensor that can avoid re-calibration due to, e.g., maintenance operations. The virtual sensor developed as a result of this research is successfully validated under real conditions on a milling centre used for the mass production of automobile engine crankshafts. Recognition accuracy, calculated with a k-fold cross validation, had on average 0.957 of true positives and 0.986 of true negatives. Moreover, measured accuracy was 98%, which suggests that the virtual sensor correctly identifies new cases. PMID:22163766

A virtual sensor for online fault detection of multitooth-tools.

PubMed

Bustillo, Andres; Correa, Maritza; Reñones, Anibal

2011-01-01

The installation of suitable sensors close to the tool tip on milling centres is not possible in industrial environments. It is therefore necessary to design virtual sensors for these machines to perform online fault detection in many industrial tasks. This paper presents a virtual sensor for online fault detection of multitooth tools based on a bayesian classifier. The device that performs this task applies mathematical models that function in conjunction with physical sensors. Only two experimental variables are collected from the milling centre that performs the machining operations: the electrical power consumption of the feed drive and the time required for machining each workpiece. The task of achieving reliable signals from a milling process is especially complex when multitooth tools are used, because each kind of cutting insert in the milling centre only works on each workpiece during a certain time window. Great effort has gone into designing a robust virtual sensor that can avoid re-calibration due to, e.g., maintenance operations. The virtual sensor developed as a result of this research is successfully validated under real conditions on a milling centre used for the mass production of automobile engine crankshafts. Recognition accuracy, calculated with a k-fold cross validation, had on average 0.957 of true positives and 0.986 of true negatives. Moreover, measured accuracy was 98%, which suggests that the virtual sensor correctly identifies new cases.

Development and testing of aluminum micro channel heat sink

NASA Astrophysics Data System (ADS)

Kumaraguruparan, G.; Sornakumar, T.

2010-06-01

Microchannel heat sinks constitute an innovative cooling technology for the removal of a large amount of heat from a small area and are suitable for electronics cooling. In the present work, Tool Steel D2 grade milling slitting saw type plain milling cutter is fabricated The microchannels are machined in aluminum work pieces to form the microchannel heat sink using the fabricated milling cutter in an horizontal milling machine. A new experimental set-up is fabricated to conduct the tests on the microchannel heat sink. The heat carried by the water increases with mass flow rate and heat input. The heat transfer coefficient and Nusselt number increases with mass flow rate and increased heat input. The pressure drop increases with Reynolds number and decreases with input heat. The friction factor decreases with Reynolds number and decreases with input heat. The thermal resistance decreases with pumping power and decreases with input heat.

Understanding and Writing G & M Code for CNC Machines

ERIC Educational Resources Information Center

Loveland, Thomas

2012-01-01

In modern CAD and CAM manufacturing companies, engineers design parts for machines and consumable goods. Many of these parts are cut on CNC machines. Whether using a CNC lathe, milling machine, or router, the ideas and designs of engineers must be translated into a machine-readable form called G & M Code that can be used to cut parts to precise…

Legionellosis Outbreak Associated with Asphalt Paving Machine, Spain, 2009

PubMed Central

Fenollar, José; Escribano, Isabel; González-Candelas, Fernando

2010-01-01

From 1999 through 2005 in Alcoi, Spain, incidence of legionellosis was continually high. Over the next 4 years, incidence was lower, but an increase in July 2009 led health authorities to declare an epidemic outbreak. A molecular epidemiology investigation showed that the allelic profiles for all Legionella pneumophila samples from the 2009 outbreak patients were the same, thus pointing to a common genetic origin for their infections, and that they were identical to that of the organism that had caused the previous outbreaks. Spatial-temporal and sequence-based typing analyses indicated a milling machine used in street asphalt repaving and its water tank as the most likely sources. As opposed to other machines used for street cleaning, the responsible milling machine used water from a natural spring. When the operation of this machine was prohibited and cleaning measures were adopted, infections ceased. PMID:20735921

Business Case Analysis of Prototype Fabrication Division Recapitalization Plan. Summary

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

Booth, Steven Richard; Benson, Faith Ann; Dinehart, Timothy Grant

Business case studies were completed to support procurement of new machines and capital equipment in the Prototype Fabrication (PF) Division SM-39 and TA-03-0102 machine shops. Economic analysis was conducted for replacing the Mazak 30Y Mill-Turn Machine in SM-39, the Haas Vertical CNC Mill in Building 102, and the Hardinge Q10/65-SP Lathe in SM-39. Analysis was also conducted for adding a NanoTech Lathe in Building 102 and a new electrical discharge machine (EDM) in SM-39 to augment current capabilities. To determine the value of switching machinery, a baseline scenario was compared with a future scenario where new machinery was purchased andmore » installed. Costs and benefits were defined via interviews with subject matter experts.« less

Milling strategies evaluation when simulating the forming dies' functional surfaces production

NASA Astrophysics Data System (ADS)

Ižol, Peter; Tomáš, Miroslav; Beňo, Jozef

2016-05-01

The paper deals with selection and evaluation of milling strategies, available in CAM systems and applicable when complicated shape parts are produced, such as forming dies. A method to obtain samples is proposed and this stems from real forming die surface machined by proper strategies. The strategy applicability for the whole part - forming die - is reviewed by the particular specimen evaluation. The presented methodology has been verified by machining model die and comparing it to the production procedure proposed in other CAM systems.

Swept Mechanism of Micro-Milling Tool Geometry Effect on Machined Oxygen Free High Conductivity Copper (OFHC) Surface Roughness

PubMed Central

Shi, Zhenyu; Liu, Zhanqiang; Li, Yuchao; Qiao, Yang

2017-01-01

Cutting tool geometry should be very much considered in micro-cutting because it has a significant effect on the topography and accuracy of the machined surface, particularly considering the uncut chip thickness is comparable to the cutting edge radius. The objective of this paper was to clarify the influence of the mechanism of the cutting tool geometry on the surface topography in the micro-milling process. Four different cutting tools including two two-fluted end milling tools with different helix angles of 15° and 30° cutting tools, as well as two three-fluted end milling tools with different helix angles of 15° and 30° were investigated by combining theoretical modeling analysis with experimental research. The tool geometry was mathematically modeled through coordinate translation and transformation to make all three cutting edges at the cutting tool tip into the same coordinate system. Swept mechanisms, minimum uncut chip thickness, and cutting tool run-out were considered on modeling surface roughness parameters (the height of surface roughness Rz and average surface roughness Ra) based on the established mathematical model. A set of cutting experiments was carried out using four different shaped cutting tools. It was found that the sweeping volume of the cutting tool increases with the decrease of both the cutting tool helix angle and the flute number. Great coarse machined surface roughness and more non-uniform surface topography are generated when the sweeping volume increases. The outcome of this research should bring about new methodologies for micro-end milling tool design and manufacturing. The machined surface roughness can be improved by appropriately selecting the tool geometrical parameters. PMID:28772479

METHODS OF TREATMENT OF COMPLEX SURFACES ON METAL CUTTING MACHINES (CHAPTERS 1 AND 12),

DTIC Science & Technology

FORGING, MOLDINGS, MANDRELS, MARINE PROPELLERS, AERIAL PROPELLERS, TURBINE BLADES, ABRASIVES, IMPELLERS, AIRCRAFT PANELS, METAL PLATES, CAMS, ELECTROEROSIVE MACHINING, CHEMICAL MILLING, MAGNETOSTRICTIVE ELEMENTS, USSR.

What Schools Are Doing: A Roundup of New and Unusual School Practices

ERIC Educational Resources Information Center

Nation's Schools, 1973

1973-01-01

Describes rumor mill,'' sheets on which community members are asked to write rumors they have heard and mail in to the superintendent; a coding system for inventory control of borrowed equipment; the use of a teletype machine in a reading program; and various mini-ideas including telephone cable core furniture, mad money'' given to students on a…

Principals' Perceptions on the Necessity to Prepare Students for Careers in Advanced Manufacturing

ERIC Educational Resources Information Center

Lee, Matthew

2015-01-01

The United States (U.S.) is undergoing a paradigm shift in manufacturing as it progresses from an era of low skill employees who stood in one place controlling machines that drilled, stamped, cut, and milled products that passed through the effective and efficient assembly line, to one that is derived from scientific inquiry and technological…

1. Perspective view of east and south elevations of Riverdale ...

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

1. Perspective view of east and south elevations of Riverdale Cotton Mill. The spinning room is located on the third floor, carding room on second floor and machine/maintenance shop on first floor. South elevation of Georgia Power powerhouse adjacent to Riverdale Mill appears on right. - Riverdale Cotton Mill, Corner of Middle & Lower Streets, Valley, Chambers County, AL

Modeling the milling tool wear by using an evolutionary SVM-based model from milling runs experimental data

NASA Astrophysics Data System (ADS)

Nieto, Paulino José García; García-Gonzalo, Esperanza; Vilán, José Antonio Vilán; Robleda, Abraham Segade

2015-12-01

The main aim of this research work is to build a new practical hybrid regression model to predict the milling tool wear in a regular cut as well as entry cut and exit cut of a milling tool. The model was based on Particle Swarm Optimization (PSO) in combination with support vector machines (SVMs). This optimization mechanism involved kernel parameter setting in the SVM training procedure, which significantly influences the regression accuracy. Bearing this in mind, a PSO-SVM-based model, which is based on the statistical learning theory, was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc. To accomplish the objective of this study, the experimental dataset represents experiments from runs on a milling machine under various operating conditions. In this way, data sampled by three different types of sensors (acoustic emission sensor, vibration sensor and current sensor) were acquired at several positions. A second aim is to determine the factors with the greatest bearing on the milling tool flank wear with a view to proposing milling machine's improvements. Firstly, this hybrid PSO-SVM-based regression model captures the main perception of statistical learning theory in order to obtain a good prediction of the dependence among the flank wear (output variable) and input variables (time, depth of cut, feed, etc.). Indeed, regression with optimal hyperparameters was performed and a determination coefficient of 0.95 was obtained. The agreement of this model with experimental data confirmed its good performance. Secondly, the main advantages of this PSO-SVM-based model are its capacity to produce a simple, easy-to-interpret model, its ability to estimate the contributions of the input variables, and its computational efficiency. Finally, the main conclusions of this study are exposed.

14. Historic American Buildings Survey PHOTOCOPY OF EVERETT MILLS, LAWRENCE, ...

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

14. Historic American Buildings Survey PHOTOCOPY OF EVERETT MILLS, LAWRENCE, MASS., INSURANCE SURVEY DRAWING n. d. From the collection of Factory Mutual Insurance Company, Norwood, Mass. - Lawrence Machine Shop, Union & Canal Streets, Lawrence, Essex County, MA

Machine grading of lumber : practical concerns for lumber producers

Treesearch

William L. Galligan; Kent A. McDonald

2000-01-01

Machine lumber grading has been applied in commercial operations in North America since 1963, and research has shown that machine grading can improve the efficient use of wood. However, industry has been reluctant to apply research findings without clear evidence that the change from visual to machine grading will be a profitable one. For instance, mill managers need...

Control of deviations and prediction of surface roughness from micro machining of THz waveguides using acoustic emission signals

NASA Astrophysics Data System (ADS)

Griffin, James M.; Diaz, Fernanda; Geerling, Edgar; Clasing, Matias; Ponce, Vicente; Taylor, Chris; Turner, Sam; Michael, Ernest A.; Patricio Mena, F.; Bronfman, Leonardo

2017-02-01

By using acoustic emission (AE) it is possible to control deviations and surface quality during micro milling operations. The method of micro milling is used to manufacture a submillimetre waveguide where micro machining is employed to achieve the required superior finish and geometrical tolerances. Submillimetre waveguide technology is used in deep space signal retrieval where highest detection efficiencies are needed and therefore every possible signal loss in the receiver has to be avoided and stringent tolerances achieved. With a sub-standard surface finish the signals travelling along the waveguides dissipate away faster than with perfect surfaces where the residual roughness becomes comparable with the electromagnetic skin depth. Therefore, the higher the radio frequency the more critical this becomes. The method of time-frequency analysis (STFT) is used to transfer raw AE into more meaningful salient signal features (SF). This information was then correlated against the measured geometrical deviations and, the onset of catastrophic tool wear. Such deviations can be offset from different AE signals (different deviations from subsequent tests) and feedback for a final spring cut ensuring the geometrical accuracies are met. Geometrical differences can impact on the required transfer of AE signals (change in cut off frequencies and diminished SNR at the interface) and therefore errors have to be minimised to within 1 μm. Rules based on both Classification and Regression Trees (CART) and Neural Networks (NN) were used to implement a simulation displaying how such a control regime could be used as a real time controller, be it corrective measures (via spring cuts) over several initial machining passes or, with a micron cut introducing a level plain measure for allowing setup corrective measures (similar to a spirit level).

Surface Roughness Optimization of Polyamide-6/Nanoclay Nanocomposites Using Artificial Neural Network: Genetic Algorithm Approach

PubMed Central

Moghri, Mehdi; Omidi, Mostafa; Farahnakian, Masoud

2014-01-01

During the past decade, polymer nanocomposites attracted considerable investment in research and development worldwide. One of the key factors that affect the quality of polymer nanocomposite products in machining is surface roughness. To obtain high quality products and reduce machining costs it is very important to determine the optimal machining conditions so as to achieve enhanced machining performance. The objective of this paper is to develop a predictive model using a combined design of experiments and artificial intelligence approach for optimization of surface roughness in milling of polyamide-6 (PA-6) nanocomposites. A surface roughness predictive model was developed in terms of milling parameters (spindle speed and feed rate) and nanoclay (NC) content using artificial neural network (ANN). As the present study deals with relatively small number of data obtained from full factorial design, application of genetic algorithm (GA) for ANN training is thought to be an appropriate approach for the purpose of developing accurate and robust ANN model. In the optimization phase, a GA is considered in conjunction with the explicit nonlinear function derived from the ANN to determine the optimal milling parameters for minimization of surface roughness for each PA-6 nanocomposite. PMID:24578636

High productivity mould robotic milling in Al-5083

NASA Astrophysics Data System (ADS)

Urresti, Iker; Arrazola, Pedro Jose; Ørskov, Klaus Bonde; Pelegay, Jose Angel

2018-05-01

Industrial serial robots were usually limited to welding, handling or spray painting operations until very recent years. However, some industries have already realized about their important capabilities in terms of flexibility, working space, adaptability and cost. Hence, currently they are seriously being considered to carry out certain metal machining tasks. Therefore, robot based machining is presented as a cost-saving and flexible manufacturing alternative compared to conventional CNC machines especially for roughing or even pre-roughing of large parts. Nevertheless, there are still some drawbacks usually referred as low rigidity, accuracy and repeatability. Thus, the process productivity is usually sacrificed getting low Material Removal Rates (MRR), and consequently not being competitive. Nevertheless, in this paper different techniques to obtain increased productivity are presented, though an appropriate selection of cutting strategies and parameters that are essential for it. During this research some rough milling tests in Al-5083 are presented where High Feed Milling (HFM) is implemented as productive cutting strategy and the experimental modal analysis named Tap-testing is used for the suitable choice of cutting conditions. Competitive productivity rates are experienced while process stability is checked through the cutting forces measurements in order to prove the effectiveness of the experimental modal analysis for robotic machining.

29 CFR 1910.212 - General requirements for all machines.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Alligator shears. (d) Power presses. (e) Milling machines. (f) Power saws. (g) Jointers. (h) Portable power tools. (i) Forming rolls and calenders. (4) Barrels, containers, and drums. Revolving drums, barrels...

DETAIL OF SPARE CONICAL CRUSHER AND GRINDING BURR WHEELS REMOVED ...

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

DETAIL OF SPARE CONICAL CRUSHER AND GRINDING BURR WHEELS REMOVED FROM THE MILLING MACHINE. - F. & H. Benning Company Oyster Mill, 14430 Solomons Island Road (moved from 1014 Benning Road, Galesville, Anne Arundel County, Maryland), Solomons, Calvert County, MD

8. VIEW OF WHEEL RACK FOR BORING MILL. Fork loading ...

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

8. VIEW OF WHEEL RACK FOR BORING MILL. Fork loading crane, manufactured by Cleveland Tramrail, 2-1/2 ton capacity. - Juniata Shops, Erecting Shop & Machine Shop, East of Fourth Avenue, between Fourth & Fifth Streets, Altoona, Blair County, PA

9. VIEW OF WHEEL RACK FOR BORING MILL. Fork loading ...

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

9. VIEW OF WHEEL RACK FOR BORING MILL. Fork loading crane, manufactured by Cleveland Tramrail, 2-1/2 ton capacity. - Juniata Shops, Erecting Shop & Machine Shop, East of Fourth Avenue, between Fourth & Fifth Streets, Altoona, Blair County, PA

Challenges in Special Steel Making

NASA Astrophysics Data System (ADS)

Balachandran, G.

2018-02-01

Special bar quality [SBQ] is a long steel product where an assured quality is delivered by the steel mill to its customer. The bars have enhanced tolerance to higher stress application and it is demanded for specialised component making. The SBQ bars are sought for component making processing units such as closed die hot forging, hot extrusion, cold forging, machining, heat treatment, welding operations. The final component quality of the secondary processing units depends on the quality maintained at the steel maker end along with quality maintained at the fabricator end. Thus, quality control is ensured at every unit process stages. The various market segments catered to by SBQ steel segment is ever growing and is reviewed. Steel mills need adequate infrastructure and technological capability to make these higher quality steels. Some of the critical stages of processing SBQ and the critical quality maintenance parameters at the steel mill in the manufacture has been brought out.

Lessons learned from the development and manufacture of ceramic reusable surface insulation materials for the space shuttle orbiters

NASA Technical Reports Server (NTRS)

Banas, R. P.; Elgin, D. R.; Cordia, E. R.; Nickel, K. N.; Gzowski, E. R.; Aguiler, L.

1983-01-01

Three ceramic, reusable surface insulation materials and two borosilicate glass coatings were used in the fabrication of tiles for the Space Shuttle orbiters. Approximately 77,000 tiles were made from these materials for the first three orbiters, Columbia, Challenger, and Discovery. Lessons learned in the development, scale up to production and manufacturing phases of these materials will benefit future production of ceramic reusable surface insulation materials. Processing of raw materials into tile blanks and coating slurries; programming and machining of tiles using numerical controlled milling machines; preparing and spraying tiles with the two coatings; and controlling material shrinkage during the high temperature (2100-2275 F) coating glazing cycles are among the topics discussed.

2. DETAIL VIEW OF MAIN ELEVATION OF MILL, LOOKING NORTHWEST. ...

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

2. DETAIL VIEW OF MAIN ELEVATION OF MILL, LOOKING NORTHWEST. NOTE ORIGINAL WINDOWS ON UPPER FLOORS. THE TOP FLOOR CONTAINED SPINNING AND TWISTER EQUIPMENT, THE SECOND FLOOR THE CARD ROOM AND ADDITIONAL SPINNING, AND THE GROUND FLOOR WEAVING, THE CLOTH ROOM, AND SHIPPING. A PARTIAL BASEMENT CONTAINED A MACHINE SHOP, SUPPLY DEPARTMENT, AND OVERFLOW COTTON STORAGE. - Stark Mill, 117 Corinth Road, Hogansville, Troup County, GA

Tool simplifies machining of pipe ends for precision welding

NASA Technical Reports Server (NTRS)

Matus, S. T.

1969-01-01

Single tool prepares a pipe end for precision welding by simultaneously performing internal machining, end facing, and bevel cutting to specification standards. The machining operation requires only one milling adjustment, can be performed quickly, and produces the high quality pipe-end configurations required to ensure precision-welded joints.

Procedure and computer program to calculate machine contribution to sawmill recovery

Treesearch

Philip H. Steele; Hiram Hallock; Stanford Lunstrum

1981-01-01

The importance of considering individual machine contribution to total mill efficiency is discussed. A method for accurately calculating machine contribution is introduced, and an example is given using this method. A FORTRAN computer program to make the necessary complex calculations automatically is also presented with user instructions.

Surgical Tooth Implants, Combat and Field.

DTIC Science & Technology

1979-12-01

conventional dental materials, usually gold. Roots are produced by grinding bisque fired alumina stock on a computer controlled milling machine. This...post and core and crown) are conventional dental materials, usually gold. Roots are produced by grinding bisque fired alumina stock on a computer...of dental implants have evolved. These devices are designed to be rigidly affixed by bone ingrowth and provide minimization of stress usually by

CAD/CAM machining Vs pre-sintering in-lab fabrication techniques of Y-TZP ceramic specimens: Effects on their mechanical fatigue behavior.

PubMed

Zucuni, C P; Guilardi, L F; Fraga, S; May, L G; Pereira, G K R; Valandro, L F

2017-07-01

This study evaluated the effects of different pre-sintering fabrication processing techniques of Y-TZP ceramic (CAD/CAM Vs. in-lab), considering surface characteristics and mechanical performance outcomes. Pre-sintered discs of Y-TZP ceramic (IPS e.max ZirCAD, Ivoclar Vivadent) were produced using different pre-sintering fabrication processing techniques: Machined- milling with a CAD/CAM system; Polished- fabrication using a cutting device followed by polishing (600 and 1200 SiC papers); Xfine- fabrication using a cutting machine followed by grinding with extra-fine diamond bur (grit size 30 μm); Fine- fabrication using a cutting machine followed by grinding with fine diamond bur (grit size 46 μm); SiC- fabrication using a cutting machine followed by grinding with 220 SiC paper. Afterwards, the discs were sintered and submitted to roughness (n=35), surface topography (n=2), phase transformation (n=2), biaxial flexural strength (n=20), and biaxial flexural fatigue strength (fatigue limit) (n=15) analyses. No monoclinic-phase content was observed in all processing techniques. It can be observed that obtaining a surface with similar characteristics to CAD/CAM milling is essential for the observation of similar mechanical performance. On this sense, grinding with fine diamond bur before sintering (Fine group) was the best mimic protocol in comparison to the CAD/CAM milling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Twin-belt continuous caster with containment and cooling of the exiting cast product for enabling high-speed casting of molten-center product

DOEpatents

Dykes, Charles D.; Daniel, Sabah S.; Wood, J. F. Barry

1990-02-20

In continuously casting molten metal into cast product by a twin-belt machine, it is desirable to achieve dramatic increases in speed (linear feet per minute) at which cast product exits the machine, particularly in installations where steel cast product is intended to feed a downstream regular rolling mill (as distinct from a planetary mill) operating in tandem with the twin-belt caster. Such high-speed casting produces product with a relatively thin shell and molten interior, and the shell tends to bulge outwardly due to metallostatic head pressure of the molten center. A number of cooperative features enable high-speed, twin-belt casting: (1) Each casting belt is slidably supported adjacent to the caster exit pulley for bulge control and enhanced cooling of cast product. (2) Lateral skew steering of each belt provides an effective increase in moving mold length plus a continuity of heat transfer not obtained with prior art belt steering apparatus. (3) The exiting slab is contained and supported downstream from the casting machine to prevent bulging of the shell of the cast product, and (4) spray cooling is incorporated in the exit containment apparatus for secondary cooling of cast product.

19. SECOND FLOOR, CARDING MACHINE, BY 'CARDING SPECIALISTS, CO., LTD., ...

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

19. SECOND FLOOR, CARDING MACHINE, BY 'CARDING SPECIALISTS, CO., LTD., PELLON LAND WORKS, HALIFAX, ENGLAND, SN #M2983 14 (EST. DATE 1940'S+). - Bamberg Cotton Mill, Main Street, Bamberg, Bamberg County, SC

INTERIOR VIEW OF MACHINE, METAL AND ELECTRIC SHOPS FROM THE ...

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

INTERIOR VIEW OF MACHINE, METAL AND ELECTRIC SHOPS FROM THE ELECTRIC SHOP. RAILROAD TRACKS IN FLOOR. VIEW FROM THE WEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

Analysis and pollution sources speculations of toxic gases in a secondary fiber paper mill.

PubMed

Tong, Xin; Liu, Zhang; Chen, Xiao Q; Shen, Wen H

2016-11-09

This paper quantitatively investigates the compositions of the gaseous pollutants in the ambient air of a secondary fiber paper mill. Total volatile organic compounds (TVOC), formaldehyde (HCHO), sulfur compounds (H2S), and hydrocarbon compounds (CxHy) were analyzed on six sampling sites with photo-ionisation detector, acetylacetone spectrophotometric method, and gas detector. The results revealed that, the high levels of TVOC and CxHy were detected at the wet end of paper machine and the office area, respectively; all the H2S contents on the six sites exceeded the limit (0.06 mg m(-3)) seriously; the HCHO concentrations at other five sites were out of the limit (0.10 mg m(-3)) except for the wastewater treatment plant. Furthermore, the necessary discussions about the possible pollution sources were considered on the process flow, the chemical agents used, and the ambient conditions in the paper mill. For the sake of air pollution control in paper mills, these remarkable results and analysis lay some technical basis in the following researches that should attract more attentions.

Experimental evaluation of tool run-out in micro milling

NASA Astrophysics Data System (ADS)

Attanasio, Aldo; Ceretti, Elisabetta

2018-05-01

This paper deals with micro milling cutting process focusing the attention on tool run-out measurement. In fact, among the effects of the scale reduction from macro to micro (i.e., size effects) tool run-out plays an important role. This research is aimed at developing an easy and reliable method to measure tool run-out in micro milling based on experimental tests and an analytical model. From an Industry 4.0 perspective this measuring strategy can be integrated into an adaptive system for controlling cutting forces, with the objective of improving the production quality, the process stability, reducing at the same time the tool wear and the machining costs. The proposed procedure estimates the tool run-out parameters from the tool diameter, the channel width, and the phase angle between the cutting edges. The cutting edge phase measurement is based on the force signal analysis. The developed procedure has been tested on data coming from micro milling experimental tests performed on a Ti6Al4V sample. The results showed that the developed procedure can be successfully used for tool run-out estimation.

110. MILL APPROACH FROM EAST. THE TRAM LINE RANT TO ...

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

110. MILL APPROACH FROM EAST. THE TRAM LINE RANT TO THE RIGHT (NORTH) OF THE ROAD AND REACHED THE CRUDE ORE BINS AROUND THE FAR BEND. BUILDINGS FROM FRONT TO BACK ARE, ON RIGHT, OIL WAREHOUSE AND GASOLINE SHED, AND ON LEFT, GARAGE, CARPENTER'S SHOP, OIL SHED, AND MACHINE SHOP. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Influence of the direction of selective laser sintering on machinability of parts from 316L steel

NASA Astrophysics Data System (ADS)

Alexeev, V. P.; Balyakin, A. V.; Khaimovich, A. I.

2017-02-01

This work presents the results of research of the impact of layer-by-layer growing of workpieces made of 316L steel on their machinability. The results of determination of residual stresses and measurement of hardness of the workpieces grown have been demonstrated. A series of experimental studies has been performed in order to determine the cutting force which occurs in the process of machining. The microstructure of the workpieces grown has been examined. It has been shown that the workpieces machined using Selective Laser Melting technology have the microstructure which is a totality of ‘microwelded seams’, which have a significant influence on the behavior of deformation processes in case of machining. The studies have shown that in case of lateral milling of the horizontally grown workpiece, the codirectional microwelded borders prevent any significant deformation of the misalignment which increases the cutting force by up to 10% as compared with milling of the vertically grown workpiece.

Business Case Analysis for Replacing the Mazak 30Y Mill-Turn Machine in SM-39. Summary

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

Booth, Steven Richard; Dinehart, Timothy Grant; Benson, Faith Ann

2015-03-19

Business case studies are being looked at to support procurement of new machines and capital equipment in the SM-39 and TA-03-0102 machine shops. The first effort conducted economic analysis of replacing the Mazak 30Y Mill-Turn Machine located in SM-39. To determine the value of switching machinery, a baseline scenario was compared with a future scenario where new machinery was purchased and installed. The conditions under the two scenarios were defined via interviews with subject matter experts in terms of one-time and periodic costs. The results of the analysis were compiled in a life-cycle cost/benefit table. The costs of procuring, installing,more » and maintaining a new machine were balanced against the costs avoided by replacing older machinery. Productivity savings were included as a measure to show the costs avoided by being able to produce parts at a quicker and more efficient pace.« less

Design and milling manufacture of polyurethane custom contoured cushions for wheelchair users.

PubMed

da Silva, Fabio Pinto; Beretta, Elisa Marangon; Prestes, Rafael Cavalli; Kindlein Junior, Wilson

2011-01-01

The design of custom contoured cushions manufactured in flexible polyurethane foams is an option to improve positioning and comfort for people with disabilities that spend most of the day seated in the same position. These surfaces increase the contact area between the seat and the user. This fact contributes to minimise the local pressures that can generate problems like decubitus ulcers. The present research aims at establishing development routes for custom cushion production to wheelchair users. This study also contributes to the investigation of Computer Numerical Control (CNC) machining of flexible polyurethane foams. The proposed route to obtain the customised seat began with acquiring the user's contour in adequate posture through plaster cast. To collect the surface geometry, the cast was three-dimensionally scanned and manipulated in CAD/CAM software. CNC milling parameters such as tools, spindle speeds and feed rates to machine flexible polyurethane foams were tested. These parameters were analysed regarding the surface quality. The best parameters were then tested in a customised seat. The possible dimensional changes generated during foam cutting were analysed through 3D scanning. Also, the customised seat pressure and temperature distribution was tested. The best parameters found for foams with a density of 50kg/cm(3) were high spindle speeds (24000 rpm) and feed rates between 2400-4000mm/min. Those parameters did not generate significant deformities in the machined cushions. The custom contoured cushion satisfactorily increased the contact area between wheelchair and user, as it distributed pressure and heat evenly. Through this study it was possible to define routes for the development and manufacturing of customised seats using direct CNC milling in flexible polyurethane foams. It also showed that custom contoured cushions efficiently distribute pressure and temperature, which is believed to minimise tissue lesions such as pressure ulcers.

20. SECOND FLOOR, CARDING MACHINE, BY 'CARDING SPECIALISTS, CO., LTD., ...

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

20. SECOND FLOOR, CARDING MACHINE, BY 'CARDING SPECIALISTS, CO., LTD., PELLON LAND WORKS, HALIFAX, ENGLAND, SN #M2983 14 (EST. DATE 1940'S+), OPPOSITE END - Bamberg Cotton Mill, Main Street, Bamberg, Bamberg County, SC

Solution of task related to control of swiss-type automatic lathe to get planes parallel to part axis

NASA Astrophysics Data System (ADS)

Tabekina, N. A.; Chepchurov, M. S.; Evtushenko, E. I.; Dmitrievsky, B. S.

2018-05-01

The work solves the problem of automation of machining process namely turning to produce parts having the planes parallel to an axis of rotation of part without using special tools. According to the results, the availability of the equipment of a high speed electromechanical drive to control the operative movements of lathe machine will enable one to get the planes parallel to the part axis. The method of getting planes parallel to the part axis is based on the mathematical model, which is presented as functional dependency between the conveying velocity of the driven element and the time. It describes the operative movements of lathe machine all over the tool path. Using the model of movement of the tool, it has been found that the conveying velocity varies from the maximum to zero value. It will allow one to carry out the reverse of the drive. The scheme of tool placement regarding the workpiece has been proposed for unidirectional movement of the driven element at high conveying velocity. The control method of CNC machines can be used for getting geometrically complex parts on the lathe without using special milling tools.

User's manual for tooth contact analysis of face-milled spiral bevel gears with given machine-tool settings

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Zhang, YI; Chen, Jui-Sheng

1991-01-01

Research was performed to develop a computer program that will: (1) simulate the meshing and bearing contact for face milled spiral beval gears with given machine tool settings; and (2) to obtain the output, some of the data is required for hydrodynamic analysis. It is assumed that the machine tool settings and the blank data will be taken from the Gleason summaries. The theoretical aspects of the program are based on 'Local Synthesis and Tooth Contact Analysis of Face Mill Milled Spiral Bevel Gears'. The difference between the computer programs developed herein and the other one is as follows: (1) the mean contact point of tooth surfaces for gears with given machine tool settings must be determined iteratively, while parameters (H and V) are changed (H represents displacement along the pinion axis, V represents the gear displacement that is perpendicular to the plane drawn through the axes of the pinion and the gear of their initial positions), this means that when V differs from zero, the axis of the pionion and the gear are crossed but not intersected; (2) in addition to the regular output data (transmission errors and bearing contact), the new computer program provides information about the contacting force for each contact point and the sliding and the so-called rolling velocity. The following topics are covered: (1) instructions for the users as to how to insert the input data; (2) explanations regarding the output data; (3) numerical example; and (4) listing of the program.

Evaluation of End Mill Coatings

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

L. J. Lazarus; R. L. Hester,

2005-08-01

Milling tests were run on families of High Speed Steel (HSS) end mills to determine their lives while machining 304 Stainless Steel. The end mills tested were made from M7, M42 and T15-CPM High Speed Steels. The end mills were also evaluated with no coatings as well as with Titanium Nitride (TiN) and Titanium Carbo-Nitride (TiCN) coatings to determine which combination of HSS and coating provided the highest increase in end mill life while increasing the cost of the tool the least. We found end mill made from M42 gave us the largest increase in tool life with the leastmore » increase in cost. The results of this study will be used by Cutting Tool Engineering in determining which end mill descriptions will be dropped from our tool catalog.« less

Nanosecond multi-pulse laser milling for certain area removal of metal coating on plastics surface

NASA Astrophysics Data System (ADS)

Zhao, Kai; Jia, Zhenyuan; Ma, Jianwei; Liu, Wei; Wang, Ling

2014-12-01

Metal coating with functional pattern on engineering plastics surface plays an important role in industry applications; it can be obtained by adding or removing certain area of metal coating on engineering plastics surface. However, the manufacturing requirements are improved continuously and the plastic substrate presents three-dimensional (3D) structure-many of these parts cannot be fabricated by conventional processing methods, and a new manufacturing method is urgently needed. As the laser-processing technology has many advantages like high machining accuracy and constraints free substrate structure, the machining of the parts is studied through removing certain area of metal coating based on the nanosecond multi-pulse laser milling. To improve the edge quality of the functional pattern, generation mechanism and corresponding avoidance strategy of the processing defects are studied. Additionally, a prediction model for the laser ablation depth is proposed, which can effectively avoid the existence of residual metal coating and reduces the damage of substrate. With the optimal machining parameters, an equiangular spiral pattern on copper-clad polyimide (CCPI) is machined based on the laser milling at last. The experimental results indicate that the edge of the pattern is smooth and consistent, the substrate is flat and without damage. The achievements in this study could be applied in industrial production.

Micro Slot Generation by μ-ED Milling

NASA Astrophysics Data System (ADS)

Dave, H. K.; Mayanak, M. K.; Rajpurohit, S. R.; Mathai, V. J.

2016-08-01

Micro electro discharge machining is one of the most widely used advanced micro machining technique owing to its capability to fabricate micro features on any electrically conductive materials irrespective of its material properties. Despite its wide acceptability, the process is always adversely affected by issues like wear that occurred on the tool electrode, which results into generation of inaccurate features. Micro ED milling, a process variant in which the tool electrode simultaneously rotated and scanned during machining, is reported to have high process efficiency for generation of 3D complicated shapes and features with relatively less electrode wear intensity. In the present study an attempt has been made to study the effect of two process parameters viz. capacitance and scanning speed of tool electrode on end wear that occurs on the tool electrode and overcut of micro slots generated by micro ED milling. The experiment has been conducted on Al 1100 alloy with tungsten electrode having diameter of 300 μm. Results suggest that wear on the tool electrode and overcut of the micro features generated are highly influenced by the level of the capacitance employed during machining. For the parameter usage employed for present study however, no significant effect of variation of scanning speed has been observed on both responses.

A High Performance Torque Sensor for Milling Based on a Piezoresistive MEMS Strain Gauge

PubMed Central

Qin, Yafei; Zhao, Yulong; Li, Yingxue; Zhao, You; Wang, Peng

2016-01-01

In high speed and high precision machining applications, it is important to monitor the machining process in order to ensure high product quality. For this purpose, it is essential to develop a dynamometer with high sensitivity and high natural frequency which is suited to these conditions. This paper describes the design, calibration and performance of a milling torque sensor based on piezoresistive MEMS strain. A detailed design study is carried out to optimize the two mutually-contradictory indicators sensitivity and natural frequency. The developed torque sensor principally consists of a thin-walled cylinder, and a piezoresistive MEMS strain gauge bonded on the surface of the sensing element where the shear strain is maximum. The strain gauge includes eight piezoresistances and four are connected in a full Wheatstone circuit bridge, which is used to measure the applied torque force during machining procedures. Experimental static calibration results show that the sensitivity of torque sensor has been improved to 0.13 mv/Nm. A modal impact test indicates that the natural frequency of torque sensor reaches 1216 Hz, which is suitable for high speed machining processes. The dynamic test results indicate that the developed torque sensor is stable and practical for monitoring the milling process. PMID:27070620

Development of an electromechanical principle for wet and dry milling

NASA Astrophysics Data System (ADS)

Halbedel, Bernd; Kazak, Oleg

2018-05-01

The paper presents a novel electromechanical principle for wet and dry milling of different materials, in which the milling beads are moved under a time- and local-variable magnetic field. A possibility to optimize the milling process in such a milling machine by simulation of the vector gradient distribution of the electromagnetic field in the process room is presented. The mathematical model and simulation methods based on standard software packages are worked out. The results of numerical simulations and experimental measurements of the electromagnetic field in the working chamber of a developed and manufactured laboratory plant correlate well with each other. Using the obtained operating parameters, dry milling experiments with crushed cement clinker and wet milling experiments of organic agents in the laboratory plant are performed and the results are discussed here.

Enabling Technologies for Advanced Soft Tissue Modeling

DTIC Science & Technology

2005-09-01

improvements 51 vivo. They also note that the in vivo condition had more to the system for future measurements. The ex vivo 107 recovery between indentations...engineering design via SolidWorks and computer-controlled milling machines (using CamWorks), managed undergraduate teaching fellows ES149 " Muscles ...2002-present (over 100 members, raised $18k) and team MVP (2004), Collegiate National Championship Div 1 competitor (2002-4), organized 100 person

Discrete element method as an approach to model the wheat milling process

USDA-ARS?s Scientific Manuscript database

It is a well-known phenomenon that break-release, particle size, and size distribution of wheat milling are functions of machine operational parameters and grain properties. Due to the non-uniformity of characteristics and properties of wheat kernels, the kernel physical and mechanical properties af...

29 CFR 1910.216 - Mills and calenders in the rubber and plastics industries.

Code of Federal Regulations, 2011 CFR

2011-07-01

... readily by pressure of the mill operator's body. (ii) Safety triprod. Installed in the front and in the.... 1910.216 Section 1910.216 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Machinery and Machine...

Low-cost boring mill

NASA Technical Reports Server (NTRS)

Hibdon, R. A.

1979-01-01

Portable unit and special fixture serve as boring mill. Machine, fabricated primarily from scrap metal, was designed and set up in about 12 working days. It has reduced setup and boring time by 66 percent as compared with existing boring miles, thereby making latter available for other jobs. Unit can be operated by one man.

The MillSOT-A Spiral Orbit Tribometer on a Milling Machine

NASA Technical Reports Server (NTRS)

Pepper, Stephen V.

2014-01-01

A spiral orbit tribometer (SOT) intended to characterize friction and wear phenomena has been constructed on a milling machine. The instrument, essentially a retainerless thrust bearing with one ball and flat races, is exceedingly simple and inexpensive to construct. The capabilities of the tribometer to measure both the coefficient of friction and contact electrical resistance are demonstrated with clean specimens as well as with well known lubricants such as molybdenum disulphide and Krytox oil. Operation in a purged environment of inert gas is also demonstrated. The results with these lubricants are quite close to what is obtained by other methods. Suggestions for extending the capabilities of the tribometer are given. This arrangement may find use in university mechanical engineering laboratories to introduce and study rolling contact motion as well as for research in contact mechanics and tribology.

Effects on Vibration and Surface Roughness in High Speed Micro End-Milling of Inconel 718 with Minimum Quantity Lubrication

NASA Astrophysics Data System (ADS)

Rahman, Mohamed Abd; Yeakub Ali, Mohammad; Saddam Khairuddin, Amir

2017-03-01

This paper presents the study on vibration and surface roughness of Inconel 718 workpiece produced by micro end-milling using Mikrotools Integrated Multi-Process machine tool DT-110 with control parameters; spindle speed (15000 rpm and 30000 rpm), feed rate (2 mm/min and 4 mm/min) and depth of cut (0.10 mm and 0.15mm). The vibration was measured using DYTRAN accelerometer instrument and the average surface roughness Ra was measured using Wyko NT1100. The analysis of variance (ANOVA) by using Design Expert software revealed that feed rate and depth of cut are the most significant factors on vibration meanwhile for average surface roughness, Ra, spindle speed is the most significant factor.

Machine Tool Series. Duty Task List.

ERIC Educational Resources Information Center

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This task list is intended for use in planning and/or evaluating a competency-based course to prepare machine tool, drill press, grinding machine, lathe, mill, and/or power saw operators. The listing is divided into six sections, with each one outlining the tasks required to perform the duties that have been identified for the given occupation.…

Fabrication of an infrared Shack-Hartmann sensor by combining high-speed single-point diamond milling and precision compression molding processes.

PubMed

Zhang, Lin; Zhou, Wenchen; Naples, Neil J; Yi, Allen Y

2018-05-01

A novel fabrication method by combining high-speed single-point diamond milling and precision compression molding processes for fabrication of discontinuous freeform microlens arrays was proposed. Compared with slow tool servo diamond broaching, high-speed single-point diamond milling was selected for its flexibility in the fabrication of true 3D optical surfaces with discontinuous features. The advantage of single-point diamond milling is that the surface features can be constructed sequentially by spacing the axes of a virtual spindle at arbitrary positions based on the combination of rotational and translational motions of both the high-speed spindle and linear slides. By employing this method, each micro-lenslet was regarded as a microstructure cell by passing the axis of the virtual spindle through the vertex of each cell. An optimization arithmetic based on minimum-area fabrication was introduced to the machining process to further increase the machining efficiency. After the mold insert was machined, it was employed to replicate the microlens array onto chalcogenide glass. In the ensuing optical measurement, the self-built Shack-Hartmann wavefront sensor was proven to be accurate in detecting an infrared wavefront by both experiments and numerical simulation. The combined results showed that precision compression molding of chalcogenide glasses could be an economic and precision optical fabrication technology for high-volume production of infrared optics.

CNC water-jet machining and cutting center

NASA Astrophysics Data System (ADS)

Bartlett, D. C.

1991-09-01

Computer Numerical Control (CNC) water-jet machining was investigated to determine the potential applications and cost-effectiveness that would result by establishing this capability in the engineering shops of Allied-Signal Inc., Kansas City Division (KCD). Both conductive and nonconductive samples were machined at KCD on conventional machining equipment (a three-axis conversational programmed mill and a wire electrical discharge machine) and on two current-technology water-jet machines at outside vendors. These samples were then inspected, photographed, and evaluated. The current-technology water-jet machines were not as accurate as the conventional equipment. The resolution of the water-jet equipment was only +/- 0.005 inch, as compared to +/- 0.0002 inch for the conventional equipment. The principal use for CNC water-jet machining would be as follows: Contouring to near finished shape those items made from 300 and 400 series stainless steels, titanium, Inconel, aluminum, glass, or any material whose fabrication tolerance is less than the machine resolution of +/- 0.005 inch; and contouring to finished shape those items made from Kevlar, rubber, fiberglass, foam, aluminum, or any material whose fabrication specifications allow the use of a machine with +/- 0.005 inch tolerance. Additional applications are possible because there is minimal force generated on the material being cut and because the water-jet cuts without generating dust.

Cyclostationarity approach for monitoring chatter and tool wear in high speed milling

NASA Astrophysics Data System (ADS)

Lamraoui, M.; Thomas, M.; El Badaoui, M.

2014-02-01

Detection of chatter and tool wear is crucial in the machining process and their monitoring is a key issue, for: (1) insuring better surface quality, (2) increasing productivity and (3) protecting both machines and safe workpiece. This paper presents an investigation of chatter and tool wear using the cyclostationary method to process the vibrations signals acquired from high speed milling. Experimental cutting tests were achieved on slot milling operation of aluminum alloy. The experimental set-up is designed for acquisition of accelerometer signals and encoding information picked up from an encoder. The encoder signal is used for re-sampling accelerometers signals in angular domain using a specific algorithm that was developed in LASPI laboratory. The use of cyclostationary on accelerometer signals has been applied for monitoring chatter and tool wear in high speed milling. The cyclostationarity appears on average properties (first order) of signals, on the energetic properties (second order) and it generates spectral lines at cyclic frequencies in spectral correlation. Angular power and kurtosis are used to analyze chatter phenomena. The formation of chatter is characterized by unstable, chaotic motion of the tool and strong anomalous fluctuations of cutting forces. Results show that stable machining generates only very few cyclostationary components of second order while chatter is strongly correlated to cyclostationary components of second order. By machining in the unstable region, chatter results in flat angular kurtosis and flat angular power, such as a pseudo (white) random signal with flat spectrum. Results reveal that spectral correlation and Wigner Ville spectrum or integrated Wigner Ville issued from second-order cyclostationary are an efficient parameter for the early diagnosis of faults in high speed machining, such as chatter, tool wear and bearings, compared to traditional stationary methods. Wigner Ville representation of the residual signal shows that the energy corresponding to the tooth passing decreases when chatter phenomenon occurs. The effect of the tool wear and the number of broken teeth on the excitation of structure resonances appears in Wigner Ville presentation.

1. Credit WCT. Original 2 1/4" x 2 1/4" color ...

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

1. Credit WCT. Original 2- 1/4" x 2- 1/4" color negative is housed in the JPL Photography Laboratory, Pasadena, California. Photo shows John Morrow in charge of milling operations on coupons ("dogbones") of propellant on an Index milling machine. Coupons were milled to precise dimensions for tensile tests. Note that two sprinkler heads have been placed in very close proximity to the milling table for fire suppression purposes (JPL negative no. JPL-10283AC, 27 January 1989) - Jet Propulsion Laboratory Edwards Facility, Preparation Building, Edwards Air Force Base, Boron, Kern County, CA

Study on Platinum Coating Depth in Focused Ion Beam Diamond Cutting Tool Milling and Methods for Removing Platinum Layer.

PubMed

Choi, Woong Kirl; Baek, Seung Yub

2015-09-22

In recent years, nanomachining has attracted increasing attention in advanced manufacturing science and technologies as a value-added processes to control material structures, components, devices, and nanoscale systems. To make sub-micro patterns on these products, micro/nanoscale single-crystal diamond cutting tools are essential. Popular non-contact methods for the macro/micro processing of diamond composites are pulsed laser ablation (PLA) and electric discharge machining (EDM). However, for manufacturing nanoscale diamond tools, these machining methods are not appropriate. Despite diamond's extreme physical properties, diamond can be micro/nano machined relatively easily using a focused ion beam (FIB) technique. In the FIB milling process, the surface properties of the diamond cutting tool is affected by the amorphous damage layer caused by the FIB gallium ion collision and implantation and these influence the diamond cutting tool edge sharpness and increase the processing procedures. To protect the diamond substrate, a protection layer-platinum (Pt) coating is essential in diamond FIB milling. In this study, the depth of Pt coating layer which could decrease process-induced damage during FIB fabrication is investigated, along with methods for removing the Pt coating layer on diamond tools. The optimum Pt coating depth has been confirmed, which is very important for maintaining cutting tool edge sharpness and decreasing processing procedures. The ultra-precision grinding method and etching with aqua regia method have been investigated for removing the Pt coating layer. Experimental results show that when the diamond cutting tool width is bigger than 500 nm, ultra-precision grinding method is appropriate for removing Pt coating layer on diamond tool. However, the ultra-precision grinding method is not recommended for removing the Pt coating layer when the cutting tool width is smaller than 500 nm, because the possibility that the diamond cutting tool is damaged by the grinding process will be increased. Despite the etching method requiring more procedures to remove the Pt coating layer after FIB milling, it is a feasible method for diamond tools with under 500 nm width.

Design and Development of an Engineering Prototype Compact X-Ray Scanner (FMS 5000)

DTIC Science & Technology

1989-03-31

machined by "wire-EDM" (electro discharge machining ). Three different slice thicknesses can be selected from the scan menu. The set of slice thicknesses...circuit. This type of circuit is used whenever more than ten kilowatts of power are needed by a machine . For example, lathes and milling machines in a... machine shop usually use this type of input power. A three- phase circuit delivers power more efficiently than a single-phase circuit because three

Vane Pump Casing Machining of Dumpling Machine Based on CAD/CAM

NASA Astrophysics Data System (ADS)

Huang, Yusen; Li, Shilong; Li, Chengcheng; Yang, Zhen

Automatic dumpling forming machine is also called dumpling machine, which makes dumplings through mechanical motions. This paper adopts the stuffing delivery mechanism featuring the improved and specially-designed vane pump casing, which can contribute to the formation of dumplings. Its 3D modeling in Pro/E software, machining process planning, milling path optimization, simulation based on UG and compiling post program were introduced and verified. The results indicated that adoption of CAD/CAM offers firms the potential to pursue new innovative strategies.

Optimizing friction stir weld parameters of aluminum and copper using conventional milling machine

NASA Astrophysics Data System (ADS)

Manisegaran, Lohappriya V.; Ahmad, Nurainaa Ayuni; Nazri, Nurnadhirah; Noor, Amirul Syafiq Mohd; Ramachandran, Vignesh; Ismail, Muhammad Tarmizizulfika; Ahmad, Ku Zarina Ku; Daruis, Dian Darina Indah

2018-05-01

The joining of two of any particular materials through friction stir welding (FSW) are done by a rotating tool and the work piece material that generates heat which causes the region near the FSW tool to soften. This in return will mechanically intermix the work pieces. The first objective of this study is to join aluminum plates and copper plates by means of friction stir welding process using self-fabricated tools and conventional milling machine. This study also aims to investigate the optimum process parameters to produce the optimum mechanical properties of the welding joints for Aluminum plates and Copper plates. A suitable tool bit and a fixture is to be fabricated for the welding process. A conventional milling machine will be used to weld the aluminum and copper. The most important parameters to enable the process are speed and pressure of the tool (or tool design and alignment of the tool onto the work piece). The study showed that the best surface finish was produced from speed of 1150 rpm and tool bit tilted to 3°. For a 200mm × 100mm Aluminum 6061 with plate thickness of 2 mm at a speed of 1 mm/s, the time taken to complete the welding is only 200 seconds or equivalent to 3 minutes and 20 seconds. The Copper plates was successfully welded using FSW with tool rotation speed of 500 rpm, 700 rpm, 900 rpm, 1150 rpm and 1440 rpm and with welding traverse rate of 30 mm/min, 60 mm/min and 90 mm/min. As the conclusion, FSW using milling machine can be done on both Aluminum and Copper plates, however the weld parameters are different for the two types of plates.

29 CFR 570.59 - Occupations involved in the operations of power-driven metal forming, punching, and shearing...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., or bending rolls; and hot or cold rolling mills. (ii) All pressing or punching machines, such as... presses; and plate punches. (iii) All bending machines, such as apron brakes and press brakes. (iv) All...

Simulation for Rough Mill Options

Treesearch

Janice K. Wiedenbeck

1992-01-01

How is rough mill production affected by lumber length? Lumber grade? Cutting quality? Cutting sizes? How would equipment purchase plans be prioritized? How do personnel shifts affect system productivity? What effect would a reduction in machine set-up time have on material flow? Simulation modeling is being widely used in many industries to provide valuable insight...

4. Long view of west half of site from Lawrence ...

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

4. Long view of west half of site from Lawrence General Hospital parking deck (former location of coating mill) showing north side of rear portion of Wilder Mill and Paper Machine Building; view to southwest. - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

Machinability evaluation of titanium alloys.

PubMed

Kikuchi, Masafumi; Okuno, Osamu

2004-03-01

In the present study, the machinability of titanium, Ti-6Al-4V, Ti-6A1-7Nb, and free-cutting brass was evaluated using a milling machine. The metals were slotted with square end mills under four cutting conditions. The cutting force and the rotational speed of the spindle were measured. The cutting forces for Ti-6Al-4V and Ti-6Al-7Nb were higher and that for brass was lower than that for titanium. The rotational speed of the spindle was barely affected by cutting. The cross sections of the Ti-6Al-4V and Ti-6Al-7Nb chips were more clearly serrated than those of titanium, which is an indication of difficult-to-cut metals. There was no marked difference in the surface roughness of the cut surfaces among the metals. Cutting force and the appearance of the metal chips were found to be useful as indices of machinability and will aid in the development of new alloys for dental CAD/CAM and the selection of suitable machining conditions.

9. Photograph of a photograph in possession of Rock Island ...

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

9. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SECOND FLOOR, EAST WING. MOTORIZED MACHINING EQUIPMENT USED IN MANUFACTURE OF MACHINE GUN PARTS. SHOWN IN THE FOREGROUND IS A PRATT & WHITNEY VERTICAL MILLING MACHINE. DATED JANUARY 21, 1943. - Rock Island Arsenal, Building No. 68, Rodman Avenue between Fourth Street & East Avenue, Rock Island, Rock Island County, IL

21. INTERIOR VIEW OF THE MACHINE SHOP LOOKING SOUTH. FROM ...

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

21. INTERIOR VIEW OF THE MACHINE SHOP LOOKING SOUTH. FROM LEFT TO RIGHT, PULLEY'S ABOVE FOR THE LATHE BELOW, ENTRANCE TO THE ELECTRICAL MOTOR ROOM, BORING MACHINE, PLANER, TOOL, BENCH AGAINST THE BACK WALL, DOORWAY INTO THE ANNEX, LONG LATHE. WOOD STOVE IN THE FOREGROUND RIGHT. - Standard Gold Mill, East of Bodie Creek, Northeast of Bodie, Bodie, Mono County, CA

Multi-Cultural Competency-Based Vocational Curricula. Machine Trades. Multi-Cultural Competency-Based Vocational/Technical Curricula Series.

ERIC Educational Resources Information Center

Hepburn, Larry; Shin, Masako

This document, one of eight in a multi-cultural competency-based vocational/technical curricula series, is on machine trades. This program is designed to run 36 weeks and cover 6 instructional areas: use of measuring tools; benchwork/tool bit grinding; lathe work; milling work; precision grinding; and combination machine work. A duty-task index…

Analysis of Flatness Deviations for Austenitic Stainless Steel Workpieces after Efficient Surface Machining

NASA Astrophysics Data System (ADS)

Nadolny, K.; Kapłonek, W.

2014-08-01

The following work is an analysis of flatness deviations of a workpiece made of X2CrNiMo17-12-2 austenitic stainless steel. The workpiece surface was shaped using efficient machining techniques (milling, grinding, and smoothing). After the machining was completed, all surfaces underwent stylus measurements in order to obtain surface flatness and roughness parameters. For this purpose the stylus profilometer Hommel-Tester T8000 by Hommelwerke with HommelMap software was used. The research results are presented in the form of 2D surface maps, 3D surface topographies with extracted single profiles, Abbott-Firestone curves, and graphical studies of the Sk parameters. The results of these experimental tests proved the possibility of a correlation between flatness and roughness parameters, as well as enabled an analysis of changes in these parameters from shaping and rough grinding to finished machining. The main novelty of this paper is comprehensive analysis of measurement results obtained during a three-step machining process of austenitic stainless steel. Simultaneous analysis of individual machining steps (milling, grinding, and smoothing) enabled a complementary assessment of the process of shaping the workpiece surface macro- and micro-geometry, giving special consideration to minimize the flatness deviations

Experimental and Mathematical Modeling for Prediction of Tool Wear on the Machining of Aluminium 6061 Alloy by High Speed Steel Tools

NASA Astrophysics Data System (ADS)

Okokpujie, Imhade Princess; Ikumapayi, Omolayo M.; Okonkwo, Ugochukwu C.; Salawu, Enesi Y.; Afolalu, Sunday A.; Dirisu, Joseph O.; Nwoke, Obinna N.; Ajayi, Oluseyi O.

2017-12-01

In recent machining operation, tool life is one of the most demanding tasks in production process, especially in the automotive industry. The aim of this paper is to study tool wear on HSS in end milling of aluminium 6061 alloy. The experiments were carried out to investigate tool wear with the machined parameters and to developed mathematical model using response surface methodology. The various machining parameters selected for the experiment are spindle speed (N), feed rate (f), axial depth of cut (a) and radial depth of cut (r). The experiment was designed using central composite design (CCD) in which 31 samples were run on SIEG 3/10/0010 CNC end milling machine. After each experiment the cutting tool was measured using scanning electron microscope (SEM). The obtained optimum machining parameter combination are spindle speed of 2500 rpm, feed rate of 200 mm/min, axial depth of cut of 20 mm, and radial depth of cut 1.0mm was found out to achieved the minimum tool wear as 0.213 mm. The mathematical model developed predicted the tool wear with 99.7% which is within the acceptable accuracy range for tool wear prediction.

Comparative evaluation of bonding strength of computer aided machined ceramic, pressable ceramic, and milled metal implant abutment copings and effect of surface conditioning on bonding strength: An in vitro study

PubMed Central

Rani, Sapna; Verma, Mahesh; Gill, Shubhra; Gupta, Rekha

2016-01-01

Background/Purpose: The aim of this study was to compare the shear bond strength of computer aided design/computer aided machined ceramic (CAD/CAM), pressable ceramic, and milled metal implant copings on abutment and the effect of surface conditioning on bonding strength. Materials and Methods: A total of 90 test samples were fabricated on three titanium abutments. Among 90 test samples, 30 copings were fabricated by CAD/CAM, 30 by pressable, and 30 by milling of titanium metal. These 30 test samples in each group were further subdivided equally for surface treatment. Fifteen out of 30 test samples in each group were surface conditioned with airborne particle abrasion. All the 90 test samples were luted on abutment with glass ionomer cement. Bonding strength was evaluated for all the samples using universal testing machine at a crosshead speed of 5 mm/min. The results obtained were compared and evaluated using one-way ANOVA with post-hoc and unpaired t-test at a significance level of 0.05. Results: The mean difference for CAD/CAM surface conditioned subgroup was 1.28 ± 0.12, for nonconditioned subgroup was 1.20 ± 0.11. The mean difference for pressable surface conditioned subgroup was 1.18 ± 0.04, and for nonconditioned subgroup was 0.75 ± 0.28. The mean difference for milled metal surface conditioned subgroup was 2.57 ± 0.58, and for nonconditioned subgroup was 1.49 ± 0.15. Conclusions: On comparison of bonding strength, milled metal copings had an edge over the other two materials, and surface conditioning increased the bond strength. PMID:27141163

22. GENERAL VIEW OF MILL FROM SOUTHEAST. PROMINENT ARE THE ...

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

22. GENERAL VIEW OF MILL FROM SOUTHEAST. PROMINENT ARE THE 100-TON STEEL CRUSHED UNOXIDIZED ORE BIN, CENTER LEFT; STEPHENS-ADAMSON 15 TON/HR INCLINED BUCKET ELEVATOR IN FRONT OF THE STEEL ORE BIN; AND THE BAKER COOLER, LOWER RIGHT. THESE MACHINES AND OTHERS IN THE AREA WERE PART OF THE UNOXIDIZED ORE CIRCUIT. THE ROASTER IS OUT OF THE PICTURE TO THE RIGHT (EAST). - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

On the bistable zone of milling processes

PubMed Central

Dombovari, Zoltan; Stepan, Gabor

2015-01-01

A modal-based model of milling machine tools subjected to time-periodic nonlinear cutting forces is introduced. The model describes the phenomenon of bistability for certain cutting parameters. In engineering, these parameter domains are referred to as unsafe zones, where steady-state milling may switch to chatter for certain perturbations. In mathematical terms, these are the parameter domains where the periodic solution of the corresponding nonlinear, time-periodic delay differential equation is linearly stable, but its domain of attraction is limited due to the existence of an unstable quasi-periodic solution emerging from a secondary Hopf bifurcation. A semi-numerical method is presented to identify the borders of these bistable zones by tracking the motion of the milling tool edges as they might leave the surface of the workpiece during the cutting operation. This requires the tracking of unstable quasi-periodic solutions and the checking of their grazing to a time-periodic switching surface in the infinite-dimensional phase space. As the parameters of the linear structural behaviour of the tool/machine tool system can be obtained by means of standard modal testing, the developed numerical algorithm provides efficient support for the design of milling processes with quick estimates of those parameter domains where chatter can still appear in spite of setting the parameters into linearly stable domains. PMID:26303918

Characteristics and Machining Performance of TiN and TiAlN Coatings on a Milling Cutter

NASA Astrophysics Data System (ADS)

Sarwar, Mohammed; Haider, Julfikar

2011-01-01

Titanium Nitride (TiN) coating deposited by Physical Vapour Deposition (PVD) or Chemical Vapour Deposition (CVD) techniques on cutting tools (single point or multipoint) has contributed towards the improvement of tool life, productivity and product quality [1]. Addition of Al in TiN coating (e.g., TiAlN or AlTiN) has further improved the coating properties required for machining applications [2, 3]. This work presents a comparative investigation on TiN and TiAlN coatings deposited on to a Powder Metallurgy High Speed Steel (PM HSS) milling cutter used for machining bimetal (M42+D6A) steel strips. PVD (Arc evaporation) technique was used to deposit the coatings after carefully preparing the cutting edges of the milling cutter. Microstructure, chemical composition, hardness and adhesion of the coatings have been characterised using different techniques. The incorporation of Al into TiN coating results in an improvement in hardness, wear resistance and cutting performance. Examination of the worn flank in the coated cutting edges revealed that abrasive and adhesive wear are the predominant failure mechanisms. Tool designers, coating suppliers and manufacturing engineers could benefit from the information provided.

Investigations on Surface Milling of Hardened AISI 4140 Steel with Pulse Jet MQL Applicator

NASA Astrophysics Data System (ADS)

Bashir, Mahmood Al; Mia, Mozammel; Dhar, Nikhil Ranjan

2018-06-01

In this article, an experimental investigation was performed in milling hardened AISI 4140 steel of hardness 40 HRC. The machining was performed in both dry and minimal quantity lubricant (MQL) conditions, as part of neat machining, to make a strong comparison of the undertaken machining environments. The MQL was impinged int the form of pulse jet, by using the specially developed pulse-jet-attachment, to ensure that the cutting fluid can be applied in different timed pulses and quantities at critical zones. The tool wear, cutting force and surface roughness were taken as the quality responses while cutting speed, table feed rate and flow rate of the pulse were considered as influential factors. The depth of cut was kept constant at 1.50 mm because of its less significant effects and the straight oil was adopted as cutting fluid in pulse-jet-MQL. The effects of different factors, on the quality responses, are analyzed using ANOVA. It is observed that MQL applicator system exhibits overall better performance when compared to dry milling by reducing surface roughness, cutting force and prolonging tool life but a flow rate of 150 ml/h has tremendous effects on the responses. This investigation and afterward results are expected to aid the industrial practitioner and researcher to adopt the pulse-MQL in high speed milling to prolong tool life, reduce tool wear, diminish cutting force generation and promote better surface finish.

Investigations on Surface Milling of Hardened AISI 4140 Steel with Pulse Jet MQL Applicator

NASA Astrophysics Data System (ADS)

Bashir, Mahmood Al; Mia, Mozammel; Dhar, Nikhil Ranjan

2016-06-01

In this article, an experimental investigation was performed in milling hardened AISI 4140 steel of hardness 40 HRC. The machining was performed in both dry and minimal quantity lubricant (MQL) conditions, as part of neat machining, to make a strong comparison of the undertaken machining environments. The MQL was impinged int the form of pulse jet, by using the specially developed pulse-jet-attachment, to ensure that the cutting fluid can be applied in different timed pulses and quantities at critical zones. The tool wear, cutting force and surface roughness were taken as the quality responses while cutting speed, table feed rate and flow rate of the pulse were considered as influential factors. The depth of cut was kept constant at 1.50 mm because of its less significant effects and the straight oil was adopted as cutting fluid in pulse-jet-MQL. The effects of different factors, on the quality responses, are analyzed using ANOVA. It is observed that MQL applicator system exhibits overall better performance when compared to dry milling by reducing surface roughness, cutting force and prolonging tool life but a flow rate of 150 ml/h has tremendous effects on the responses. This investigation and afterward results are expected to aid the industrial practitioner and researcher to adopt the pulse-MQL in high speed milling to prolong tool life, reduce tool wear, diminish cutting force generation and promote better surface finish.

Preparation of Mo-Re-C samples containing Mo{sub 7}Re{sub 13}C with the β-Mn-type structure by solid state reaction of planetary-ball-milled powder mixtures of Mo, Re and C, and their crystal structures and superconductivity

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

Oh-ishi, Katsuyoshi, E-mail: oh-ishi@kc.chuo-u.ac.jp; Nagumo, Kenta; Tateishi, Kazuya

Mo-Re-C compounds containing Mo{sub 7}Re{sub 13}C with the β-Mn structure were synthesized with high-melting-temperature metals Mo, Re, and C powders using a conventional solid state method with a planetary ball milling machine instead of the arc melting method. Use of the ball milling machine was necessary to obtain Mo{sub 7}Re{sub 13}C with the β-Mn structure using the solid state method. Almost single-phase Mo{sub 7}Re{sub 13}C with a trace of impurity were obtained using the synthesis method. By XRF and lattice parameter measurements on the samples, Fe element existed in the compound synthesized using the planetary ball milling machine with amore » pot and balls made of steel, though Fe element was not detected in the compound synthesized using a pot and balls made of tungsten carbide. The former compound containg the Fe atom did not show superconductivity but the latter compound without the Fe atom showed superconductivity at 6.1 K. - Graphical abstract: Temperature dependence of the magnetic susceptibility measured under 10 Oe for the superconducting PBM-T samples without Fe element and non-superconducting PBM-S with Fe element. The inset is the enlarged view of the data for the PBM-S sample.« less

Continuous internal channels formed in aluminum fusion welds

NASA Technical Reports Server (NTRS)

Gault, J.; Sabo, W.

1967-01-01

Process produces continuous internal channel systems on a repeatable basis in 2014-T6 aluminum. Standard machining forms the initial channel, which is filled with tungsten carbide powder. TIG machine fusion welding completes formation of the channel. Chem-mill techniques enlarge it to the desired size.

The influence of lumber grade on machine productivity in the rough mill

Treesearch

Philip H. Steele; Jan Wiedenbeck; Rubin Shmulsky; Anura Perera; Anura Perera

1999-01-01

Lumber grade effect on hardwood-part processing time was investigated with a digitally described lumber database in conjunction with a crosscut-first rough mill yield optimization simulator. In this study, the digital lumber sample was subdivided into five hardwood lumber grades. Three cutting bills with varying degrees of difficulty were Cut." The three cutting...

6. VIEW OF BORING MILL. Chuck action of locomotive wheel ...

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

6. VIEW OF BORING MILL. Chuck action of locomotive wheel Wheel weight 1200 pounds, 3'-0' diameter. Table 53' in diameter Wheel is 48'. Largest hole that can be bored is 9-1/2' plus (GE axle is 10'). - Juniata Shops, Erecting Shop & Machine Shop, East of Fourth Avenue, between Fourth & Fifth Streets, Altoona, Blair County, PA

Flexible Manufacturing System Handbook. Volume II. Description of the Technology

DTIC Science & Technology

1983-02-01

hubs, or wheels with considerable 4 FM5 Handbook, Volume II milling, drilling and/or tapping, are usually candidates for inclusion in a prismatic...0.06 inch) to transfer pallets to a machine or unload station. Wheel encoders can be used as less precise feedback for the drive system and its...must be used to control pallet transfer. The Cincinnati Milacron Variable Mission System uses this type of MHS, specifically the Eaton-Kenway Robo

Comparison study on disturbance estimation techniques in precise slow motion control

NASA Astrophysics Data System (ADS)

Fan, S.; Nagamune, R.; Altintas, Y.; Fan, D.; Zhang, Z.

2010-08-01

Precise low speed motion control is important for the industrial applications of both micro-milling machine tool feed drives and electro-optical tracking servo systems. It calls for precise position and instantaneous velocity measurement and disturbance, which involves direct drive motor force ripple, guide way friction and cutting force etc., estimation. This paper presents a comparison study on dynamic response and noise rejection performance of three existing disturbance estimation techniques, including the time-delayed estimators, the state augmented Kalman Filters and the conventional disturbance observers. The design technique essentials of these three disturbance estimators are introduced. For designing time-delayed estimators, it is proposed to substitute Kalman Filter for Luenberger state observer to improve noise suppression performance. The results show that the noise rejection performances of the state augmented Kalman Filters and the time-delayed estimators are much better than the conventional disturbance observers. These two estimators can give not only the estimation of the disturbance but also the low noise level estimations of position and instantaneous velocity. The bandwidth of the state augmented Kalman Filters is wider than the time-delayed estimators. In addition, the state augmented Kalman Filters can give unbiased estimations of the slow varying disturbance and the instantaneous velocity, while the time-delayed estimators can not. The simulation and experiment conducted on X axis of a 2.5-axis prototype micro milling machine are provided.

Determination of Machining Parameters of Corn Byproduct Filled Plastics

USDA-ARS?s Scientific Manuscript database

In a collaborative project between the USDA and Northern Illinois University, the use of ethanol corn processing by-products as bio-filler materials in the compression molding of phenolic plastics has been studied. This paper reports on the results of a machinability study in the milling of various ...

Determining Machining Parameters of Corn Byproduct Filled Plastics

USDA-ARS?s Scientific Manuscript database

In a collaborative project between the USDA and Northern Illinois University, the use of corn ethanol processing byproducts (i.e., DDGS) as bio-filler materials in the compression molding of phenolic plastics has been studied. This paper reports on the results of a machinability study in the milling...

Machine-related injuries in the US mining industry and priorities for safety research.

PubMed

Ruff, Todd; Coleman, Patrick; Martini, Laura

2011-03-01

Researchers at the National Institute for Occupational Safety and Health studied mining accidents that involved a worker entangled in, struck by, or in contact with machinery or equipment in motion. The motivation for this study came from the large number of severe accidents, i.e. accidents resulting in a fatality or permanent disability, that are occurring despite available interventions. Accident descriptions were taken from an accident database maintained by the United States Department of Labor, Mine Safety and Health Administration, and 562 accidents that occurred during 2000-2007 fit the search criteria. Machine-related accidents accounted for 41% of all severe accidents in the mining industry during this period. Machinery most often involved in these accidents included conveyors, rock bolting machines, milling machines and haulage equipment such as trucks and loaders. The most common activities associated with these accidents were operation of the machine and maintenance and repair. The current methods to safeguard workers near machinery include mechanical guarding around moving components, lockout/tagout of machine power during maintenance and backup alarms for mobile equipment. To decrease accidents further, researchers recommend additional efforts in the development of new control technologies, training materials and dissemination of information on best practices.

Quick-Turn Finite Element Analysis for Plug-and-Play Satellite Structures

DTIC Science & Technology

2007-03-01

produced from 0.375 inch round stock and turned on a machine lathe to achieve the shoulder feature and drilled to make it hollow. Figure 3.1...component, a linear taper was machined from the connection shoulder to the solar panel connecting fork. The part was then turned using the machine lathe ...utilizing a modern five-axis Computer Numerical Code ( CNC ) machine mill, the process time could be reduced by as much as seventy-five percent and the

Toolpath strategy for cutter life improvement in plunge milling of AISI H13 tool steel

NASA Astrophysics Data System (ADS)

Adesta, E. Y. T.; Avicenna; hilmy, I.; Daud, M. R. H. C.

2018-01-01

Machinability of AISI H13 tool steel is a prominent issue since the material has the characteristics of high hardenability, excellent wear resistance, and hot toughness. A method of improving cutter life of AISI H13 tool steel plunge milling by alternating the toolpath and cutting conditions is proposed. Taguchi orthogonal array with L9 (3^4) resolution will be employed with one categorical factor of toolpath strategy (TS) and three numeric factors of cutting speed (Vc), radial depth of cut (ae ), and chip load (fz ). It is expected that there are significant differences for each application of toolpath strategy and each cutting condition factor toward the cutting force and tool wear mechanism of the machining process, and medial axis transform toolpath could provide a better tool life improvement by a reduction of cutting force during machining.

The Impacts of Industrial Robots

DTIC Science & Technology

1981-11-01

plastics, ’and strain gauges are used to measure very small forces at a number of points on the robot’s "end effector. Except for the simplest on-off...devices, tactile sensors are not yet found on commercially available robots. Forces are sensed by using strain gauges or piezoelectric sensors to...tools: deburring, drilling , grinding,milling,routing machines ii. plastic materialsformirg and injection machines iii. metal die casting machines iv

Micro Machining of Injection Mold Inserts for Fluidic Channel of Polymeric Biochips

PubMed Central

Jung, Woo-Chul; Heo, Young-Moo; Yoon, Gil-Sang; Shin, Kwang-Ho; Chang, Sung-Ho; Kim, Gun-Hee; Cho, Myeong-Woo

2007-01-01

Recently, the polymeric micro-fluidic biochip, often called LOC (lab-on-a-chip), has been focused as a cheap, rapid and simplified method to replace the existing biochemical laboratory works. It becomes possible to form miniaturized lab functionalities on a chip with the development of MEMS technologies. The micro-fluidic chips contain many micro-channels for the flow of sample and reagents, mixing, and detection tasks. Typical substrate materials for the chip are glass and polymers. Typical techniques for microfluidic chip fabrication are utilizing various micro pattern forming methods, such as wet-etching, micro-contact printing, and hot-embossing, micro injection molding, LIGA, and micro powder blasting processes, etc. In this study, to establish the basis of the micro pattern fabrication and mass production of polymeric micro-fluidic chips using injection molding process, micro machining method was applied to form micro-channels on the LOC molds. In the research, a series of machining experiments using micro end-mills were performed to determine optimum machining conditions to improve surface roughness and shape accuracy of designed simplified micro-channels. Obtained conditions were used to machine required mold inserts for micro-channels using micro end-mills. Test injection processes using machined molds and COC polymer were performed, and then the results were investigated.

Paterson, New Jersey: America's Silk City. Teaching with Historic Places.

ERIC Educational Resources Information Center

Koman, Rita G.

Paterson, New Jersey, was established in the 1790s to utilize the power of the water that cascades through the Passaic River Gorge. Massive brick mill buildings lined the canals that transformed the power of the falls into energy to drive machines. These mills manufactured many things during the history of this industrial city. In the late 19th…

Some technical aspects of trimming lumber in the planing mill

Treesearch

Peter Koch

1952-01-01

This paper discusses four classes of lumber timming machines applicable to the planning mill. The classification is made according to function as follows: Irregularity or defect removal to increase the value of residual portion. Double end trimming to a length standard acceptable by the trade, trimming to specified length of the higher grades of stock after it has been...

Diagnostics of flexible workpiece using acoustic emission, acceleration and eddy current sensors in milling operation

NASA Astrophysics Data System (ADS)

Filippov, A. V.; Tarasov, S. Yu.; Filippova, E. O.; Chazov, P. A.; Shamarin, N. N.; Podgornykh, O. A.

2016-11-01

Monitoring of the edge clamped workpiece deflection during milling has been carried our using acoustic emission, accelerometer and eddy current sensors. Such a monitoring is necessary in precision machining of vital parts used in air-space engineering where a majority of them made by milling. The applicability of the AE, accelerometers and eddy current sensors has been discussed together with the analysis of measurement errors. The appropriate sensor installation diagram has been proposed for measuring the workpiece elastic deflection exerted by the cutting force.

4. TROJAN MILL, DETAIL OF CRUDE ORE BINS FROM NORTH, ...

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

4. TROJAN MILL, DETAIL OF CRUDE ORE BINS FROM NORTH, c. 1912. SHOWS TIMBER FRAMING UNDER CONSTRUCTION FOR EAST AND WEST CRUDE ORE BINS AT PREVIOUS LOCATION OF CRUSHER HOUSE, AND SNOW SHED PRESENT OVER SOUTH CRUDE ORE BIN WITH PHASE CHANGE IN SNOW SHED CONSTRUCTION INDICATED AT EAST END OF EAST CRUDE ORE BIN. THIS PHOTOGRAPH IS THE FIRST IMAGE OF THE MACHINE SHOP, UPPER LEFT CORNER. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Cold Saw Operator (iron & steel) 6-88.651; Cold Sizing Mill Operator (iron & steel) 4-88.315; Decambering Mill Operator (iron & steel) 6-88.346; Flying Cut-Off Machine Operator (iron & steel) 6-88.655; Rotary Straightener Operator (iron & steel) 6-88.346; Straightener Machine Operator (iron & steel) 6-88.354; Tube Straightener Operator (iron & steel) 6-88.346; Welder (iron & steel) 4-88.343; Welder, Assistant (iron & steel) 4-88.344--Technical

ERIC Educational Resources Information Center

Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.

The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…

Optimization of Milling Parameters Employing Desirability Functions

NASA Astrophysics Data System (ADS)

Ribeiro, J. L. S.; Rubio, J. C. Campos; Abrão, A. M.

2011-01-01

The principal aim of this paper is to investigate the influence of tool material (one cermet and two coated carbide grades), cutting speed and feed rate on the machinability of hardened AISI H13 hot work steel, in order to identify the cutting conditions which lead to optimal performance. A multiple response optimization procedure based on tool life, surface roughness, milling forces and the machining time (required to produce a sample cavity) was employed. The results indicated that the TiCN-TiN coated carbide and cermet presented similar results concerning the global optimum values for cutting speed and feed rate per tooth, outperforming the TiN-TiCN-Al2O3 coated carbide tool.

Improving Energy Efficiency in CNC Machining

NASA Astrophysics Data System (ADS)

Pavanaskar, Sushrut S.

We present our work on analyzing and improving the energy efficiency of multi-axis CNC milling process. Due to the differences in energy consumption behavior, we treat 3- and 5-axis CNC machines separately in our work. For 3-axis CNC machines, we first propose an energy model that estimates the energy requirement for machining a component on a specified 3-axis CNC milling machine. Our model makes machine-specific predictions of energy requirements while also considering the geometric aspects of the machining toolpath. Our model - and the associated software tool - facilitate direct comparison of various alternative toolpath strategies based on their energy-consumption performance. Further, we identify key factors in toolpath planning that affect energy consumption in CNC machining. We then use this knowledge to propose and demonstrate a novel toolpath planning strategy that may be used to generate new toolpaths that are inherently energy-efficient, inspired by research on digital micrography -- a form of computational art. For 5-axis CNC machines, the process planning problem consists of several sub-problems that researchers have traditionally solved separately to obtain an approximate solution. After illustrating the need to solve all sub-problems simultaneously for a truly optimal solution, we propose a unified formulation based on configuration space theory. We apply our formulation to solve a problem variant that retains key characteristics of the full problem but has lower dimensionality, allowing visualization in 2D. Given the complexity of the full 5-axis toolpath planning problem, our unified formulation represents an important step towards obtaining a truly optimal solution. With this work on the two types of CNC machines, we demonstrate that without changing the current infrastructure or business practices, machine-specific, geometry-based, customized toolpath planning can save energy in CNC machining.

Real-Time Deflection Monitoring for Milling of a Thin-Walled Workpiece by Using PVDF Thin-Film Sensors with a Cantilevered Beam as a Case Study

PubMed Central

Luo, Ming; Liu, Dongsheng; Luo, Huan

2016-01-01

Thin-walled workpieces, such as aero-engine blisks and casings, are usually made of hard-to-cut materials. The wall thickness is very small and it is easy to deflect during milling process under dynamic cutting forces, leading to inaccurate workpiece dimensions and poor surface integrity. To understand the workpiece deflection behavior in a machining process, a new real-time nonintrusive method for deflection monitoring is presented, and a detailed analysis of workpiece deflection for different machining stages of the whole machining process is discussed. The thin-film polyvinylidene fluoride (PVDF) sensor is attached to the non-machining surface of the workpiece to copy the deflection excited by the dynamic cutting force. The relationship between the input deflection and the output voltage of the monitoring system is calibrated by testing. Monitored workpiece deflection results show that the workpiece experiences obvious vibration during the cutter entering the workpiece stage, and vibration during the machining process can be easily tracked by monitoring the deflection of the workpiece. During the cutter exiting the workpiece stage, the workpiece experiences forced vibration firstly, and free vibration exists until the amplitude reduces to zero after the cutter exits the workpiece. Machining results confirmed the suitability of the deflection monitoring system for machining thin-walled workpieces with the application of PVDF sensors. PMID:27626424

The need for artificial intelligence as an aid in controlling a manufacturing operation

NASA Astrophysics Data System (ADS)

Weyand, J.

AI applications to industrial production and planning are discussed and illustrated with diagrams and drawings. Applications examined include flexible automation of manufacturing processes (robots with open manual control, robots programmable to meet product specifications, self-regulated robots, and robots capable of learning), flexible fault detection and diagnostics, production control, and overall planning and management (product strategies, marketing, determination of development capacity, site selection, project organization, and technology investment strategies). For the case of robots, problems in the design and operation of a state-of-the-art machine-tool cell (for hole boring, milling, and joining) are analyzed in detail.

Corner smoothing of 2D milling toolpath using b-spline curve by optimizing the contour error and the feedrate

NASA Astrophysics Data System (ADS)

Özcan, Abdullah; Rivière-Lorphèvre, Edouard; Ducobu, François

2018-05-01

In part manufacturing, efficient process should minimize the cycle time needed to reach the prescribed quality on the part. In order to optimize it, the machining time needs to be as low as possible and the quality needs to meet some requirements. For a 2D milling toolpath defined by sharp corners, the programmed feedrate is different from the reachable feedrate due to kinematic limits of the motor drives. This phenomena leads to a loss of productivity. Smoothing the toolpath allows to reduce significantly the machining time but the dimensional accuracy should not be neglected. Therefore, a way to address the problem of optimizing a toolpath in part manufacturing is to take into account the manufacturing time and the part quality. On one hand, maximizing the feedrate will minimize the manufacturing time and, on the other hand, the maximum of the contour error needs to be set under a threshold to meet the quality requirements. This paper presents a method to optimize sharp corner smoothing using b-spline curves by adjusting the control points defining the curve. The objective function used in the optimization process is based on the contour error and the difference between the programmed feedrate and an estimation of the reachable feedrate. The estimation of the reachable feedrate is based on geometrical information. Some simulation results are presented in the paper and the machining times are compared in each cases.

Triaxial X-Ray Diffraction Method and its Application to Monitor Residual Stress in Surface Layers after High-Feed Milling

NASA Astrophysics Data System (ADS)

Zaušková, Lucia; Czán, Andrej; Šajgalík, Michal; Pobijak, Jozef; Mikloš, Matej

2017-10-01

High-feed milling is a milling method characteristic with shallow depth of cut and high feed rate to maximize the amount of removed metal from a part, generating residual stresses in the surface and subsurface layers of the machined parts. The residual stress has a large influence on the functional properties of the components. The article is focused on the application of triaxial x-ray diffraction method to monitor residual stresses after high feed milling. Significance of triaxial measuring method is the capability of measuring in different angles so it is possible to acquire stress tensor containing normal and shear stress components.

An experimental study of flank wear in the end milling of AISI 316 stainless steel with coated carbide inserts

NASA Astrophysics Data System (ADS)

Odedeyi, P. B.; Abou-El-Hossein, K.; Liman, M.

2017-05-01

Stainless steel 316 is a difficult-to-machine iron-based alloys that contain minimum of about 12% of chromium commonly used in marine and aerospace industry. This paper presents an experimental study of the tool wear propagation variations in the end milling of stainless steel 316 with coated carbide inserts. The milling tests were conducted at three different cutting speeds while feed rate and depth of cut were at (0.02, 0.06 and 01) mm/rev and (1, 2 and 3) mm, respectively. The cutting tool used was TiAlN-PVD-multi-layered coated carbides. The effects of cutting speed, cutting tool coating top layer and workpiece material were investigated on the tool life. The results showed that cutting speed significantly affected the machined flank wears values. With increasing cutting speed, the flank wear values decreased. The experimental results showed that significant flank wear was the major and predominant failure mode affecting the tool life.

USSR Report, Machine Tools and Metalworking Equipment, No. 6

DTIC Science & Technology

1983-05-18

production output per machine tool at a tool plant average 2-3 times the figures for tool shops. This is explained by the well-known advantages of...specialized production. Specifically, the advantages of standardization and unification of machine- attachment design can be fully exploited in...lemiiiiä IS MVCti\\e UtiUzation °f appropriate special equipmeT ters)! million thread-cutting dies, and 2.3 million milling cut- The advantages of

Submicron particle monitoring of paving and related road construction operations.

PubMed

Freund, Alice; Zuckerman, Norman; Baum, Lisa; Milek, Debra

2012-01-01

This study identified activities and sources that contribute to ultrafine and other submicron particle exposure that could trigger respiratory symptoms in highway repair workers. Submicron particle monitoring was conducted for paving, milling, and pothole repair operations in a major metropolitan area where several highway repair workers were identified as symptomatic for respiratory illness following exposures at the 2001 World Trade Center disaster site. Exposure assessments were conducted for eight trades involved in road construction using a TSI P-Trak portable condensation particle counter. Direct readings near the workers' breathing zones and observations of activities and potential sources were logged on 7 days on 27 workers using four different models of pavers and two types of millers. Average worker exposure levels ranged from 2 to 3 times background during paving and from 1 to 4 times background during milling. During asphalt paving, average personal exposures to submicron particulates were 25,000-60,000, 28,000-70,000, and 23,000-37,000 particles/ cm(3) for paver operators, screed operators, and rakers, respectively. Average personal exposures during milling were 19,000-111,000, 28,000-81,000, and 19,000 particles/cm(3) for the large miller operators, miller screed operators, and raker, respectively. Personal peak exposures were measured up to 467,000 and 455,000 particles/cm(3) in paving and milling, respectively. Several sources of submicron particles were identified. These included the diesel and electric fired screed heaters; engine exhaust from diesel powered construction vehicles passing by or idling; raking, dumping, and paving of asphalt; exhaust from the hotbox heater; pavement dust or fumes from milling operations, especially when the large miller started and stopped; and secondhand cigarette smoke. To reduce the potential for health effects in workers, over 40 recommendations were made to control exposures, including improved maintenance of paver ventilation systems; diesel fume engineering controls; reduced idling; provision of cabs for the operators; and improved dust suppression systems on the milling machine.

Doppler ultrasound compatible plastic material for use in rigid flow models.

PubMed

Wong, Emily Y; Thorne, Meghan L; Nikolov, Hristo N; Poepping, Tamie L; Holdsworth, David W

2008-11-01

A technique for the rapid but accurate fabrication of multiple flow phantoms with variations in vascular geometry would be desirable in the investigation of carotid atherosclerosis. This study demonstrates the feasibility and efficacy of implementing numerically controlled direct-machining of vascular geometries into Doppler ultrasound (DUS)-compatible plastic for the easy fabrication of DUS flow phantoms. Candidate plastics were tested for longitudinal speed of sound (SoS) and acoustic attenuation at the diagnostic frequency of 5 MHz. Teflon was found to have the most appropriate SoS (1376 +/- 40 m s(-1) compared with 1540 m s(-1) in soft tissue) and thus was selected to construct a carotid bifurcation flow model with moderate eccentric stenosis. The vessel geometry was machined directly into Teflon using a numerically controlled milling technique. Geometric accuracy of the phantom lumen was verified using nondestructive micro-computed tomography. Although Teflon displayed a higher attenuation coefficient than other tested materials, Doppler data acquired in the Teflon flow model indicated that sufficient signal power was delivered throughout the depth of the vessel and provided comparable velocity profiles to that obtained in the tissue-mimicking phantom. Our results indicate that Teflon provides the best combination of machinability and DUS compatibility, making it an appropriate choice for the fabrication of rigid DUS flow models using a direct-machining method.

21. INTERIOR VIEW, UNDER THE MAIN FLOOR SHOWING THE LINESHAFT ...

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

21. INTERIOR VIEW, UNDER THE MAIN FLOOR SHOWING THE LINESHAFT SYSTEM ONCE POWERED BY A STEAM ENGINE AND LATER BY TWO LARGE ELECTRICAL MILL MOTORS (NOTICE LARGE GEAR IN FOREGROUND) THAT OPERATED EACH NAIL MACHINE; PRESENTLY THE NAIL MACHINES ARE DRIVEN BY INDIVIDUAL ELECTRICAL MOTORS - LaBelle Iron Works, Thirtieth & Wood Streets, Wheeling, Ohio County, WV

18. VIEW OF CRUDE ORE BINS FROM WEST. WEST CRUDE ...

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

18. VIEW OF CRUDE ORE BINS FROM WEST. WEST CRUDE ORE BIN AND TRESTLE FROM TWO JOHNS TRAMLINE TO SOUTH, CRUDE ORE BIN IN FOREGROUND. MACHINE SHOP IN BACKGROUND. THE TRAM TO PORTLAND PASSED TO NORTH OF MACHINE SHOP. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Production Engineering Program to Develop Improved Mass-Production Process for M42/M46 Grenade Bodies

DTIC Science & Technology

1978-03-01

J16 Photograph 3 Knurling Tool Installed in Machine . . ....... 16 Photograph 4 Shrapnel Pattern Being Knurled Into M42 Grenade Cylinder...body Fenn mill embossing rolls. Roehlen was awarded a cuxiu**L am’i labricated a knurling tool for use in the modified Tesker thread-rolling machine ...automatic grinding machine . IKratz-Wilde was not successful in developing tooling to produce domes to the inertia-welded assembly design. (See Figure

Magnesium Nanocomposites: Current Status and Prospects for Army Applications

DTIC Science & Technology

2011-09-01

and reinforcement that cannot be produced through melt-based processing . In mechanical alloying , the powder and milling media are placed into...mixing vessels that are agitated in a high-energy milling machine. During the mixing process , the powder particles undergo repeated cycles of cold ...welding and fracturing of interparticle bonds. At the end of the process , the powder has been alloyed to the desired composition. Although typically used

VIEW IN OPPOSITE DIRECTION AS MD1351 AND MD1352. RAW MATERIAL ...

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

VIEW IN OPPOSITE DIRECTION AS MD-135-1 AND MD-135-2. RAW MATERIAL CONVEYOR AT LEFT DEPOSITS SHELL INTO MILLING MACHINE AT LOWER LEFT. ENGINE IS AT LOWER RIGHT AND RADIATOR AT LOWER CENTER. ROLLER SORTER IS AT TOP OF CONVEYOR. - F. & H. Benning Company Oyster Mill, 14430 Solomons Island Road (moved from 1014 Benning Road, Galesville, Anne Arundel County, Maryland), Solomons, Calvert County, MD

Effect of CNC-milling on the marginal and internal fit of dental ceramics: a pilot study.

PubMed

Schaefer, Oliver; Kuepper, Harald; Thompson, Geoffrey A; Cachovan, Georg; Hefti, Arthur F; Guentsch, Arndt

2013-08-01

Machined restorations have been investigated for their preciseness before, while detailed information on the milling-step itself are lacking. Therefore, the aim of this laboratory study was to quantify the effect of a novel milling-procedure on the marginal and internal fit of ceramic restorations. An acrylic model of a lower left first molar was prepared to receive a ceramic partial crown and was duplicated by one step dual viscosity impressions. Gypsum casts were formed and laser-scanned to realize virtual datasets, before restorations were designed, exported (PRE) and machined from lithium disilicate blanks. Crowns were digitized by a structure-light-scanner to obtain post-milling-data (POST). PRE and POST were virtually superimposed on the reference tooth and subjected to computer-aided-inspection. Visual fit-discrepancies were displayed with colors, while root mean square deviations (RMSD) and degrees of similarity (DS) were computed and analysed by t-tests for paired samples (n=5, α=0.05). The milling procedure resulted in a small increase of the marginal and internal fit discrepancies (RMSD mean: 3μm and 6μm, respectively). RMSD differences were not statistically significant (p=0.495 and p=0.160 for marginal and internal fit, respectively). These results were supported by the DS data. The products of digital dental workflows are prone to imprecisions. However, the present findings suggest that differences between computer-aided designed and actually milled restorations are small, especially when compared to typical fit discrepancies observed clinically. Imprecisions introduced by digital design or production processes are small. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Study on the surface constitute properties of high-speed end milling aluminum alloy

NASA Astrophysics Data System (ADS)

Huang, Xiaoming; Li, Hongwei; Yumeng, Ma

2017-09-01

The physical and mechanical properties of the metal surface will change after the metal cutting processing. The comprehensive study of the influence of machining parameters on surface constitute properties are necessary. A high-speed milling experiment by means of orthogonal method with four factors was conducted for aluminum alloy7050-T7451. The surface constitutive properties of the Al-Alloy surface were measured using SSM-B4000TM stress-strain microprobe system. Based on all the load-depth curves obtained, the characteristics parameters such as strain hardening exponent n and yield strength σy of the milling surface are calculated. The effect of cutting speed, feed rate, and width and depth of cut on n and σy was investigated using the ANOVA techniques. The affecting degree of milling parameters on n and σy was v>fz> ap < ae. The influence of milling parameters on n and σ y was described and discussed.

A Study on Micro-Machining Technology for the Machining of NiTi: Five-Axis Micro-Milling and Micro Deep-Hole Drilling

NASA Astrophysics Data System (ADS)

Biermann, D.; Kahleyss, F.; Krebs, E.; Upmeier, T.

2011-07-01

Micro-sized applications are gaining more and more relevance for NiTi-based shape memory alloys (SMA). Different types of micro-machining offer unique possibilities for the manufacturing of NiTi components. The advantage of machining is the low thermal influence on the workpiece. This is important, because the phase transformation temperatures of NiTi SMAs can be changed and the components may need extensive post manufacturing. The article offers a simulation-based approach to optimize five-axis micro-milling processes with respect to the special material properties of NiTi SMA. Especially, the influence of the various tool inclination angles is considered for introducing an intelligent tool inclination optimization algorithm. Furthermore, aspects of micro deep-hole drilling of SMAs are discussed. Tools with diameters as small as 0.5 mm are used. The possible length-to-diameter ratio reaches up to 50. This process offers new possibilities in the manufacturing of microstents. The study concentrates on the influence of the cutting speed, the feed and the tool design on the tool wear and the quality of the drilled holes.

Application of ultrafiltration in the pulp and paper industry: metals removal and whitewater reuse.

PubMed

Oliveira, C R; Silva, C M; Milanez, A F

2007-01-01

In the pulp and paper industry, the water use minimization is a constant target. One way to reduce water use is to recycle the effluent in a closed-cycle concept. In paper mills, the main source of liquid effluent is the so-called whitewater, which is the excess water, originated from pulp stock dewatering and other fibre contaminated water. This research studied the reuse of paper mill whitewater after membrane ultrafiltration (UF) in the paper machine and in the pulp bleach plant of an integrated mill. Contaminant removal and flux behaviour of the UF system were evaluated. The treatment by ultrafiltration was technically feasible and the treated whitewater had good potential to be reused in some processes in the paper machine. The reuse of ultrafiltered whitewater in the bleaching plant was not recommended because of the high level of soluble calcium present in this stream. Therefore, a combined treatment of the whitewater using the principle of precipitation and ultrafiltration was proposed showing good results and enabling the use of the treated whitewater in the bleach plant.

Superhydrophobic surface prepared by micro-milling and WEDM on aluminum alloy

NASA Astrophysics Data System (ADS)

Yanling, Wan; Jian, Yang; Huadong, Yu

2018-06-01

To simulate the hydrophobic microstructure of rice leaf surface, high-speed precision micro-milling machine was used to fabricate micro groove array structure on the surface of aluminum alloy. The micro-and nanostructure was constructed on the surface of the grooved convex platform by Wire Cut Electrical Discharge Machining (WEDM). The surface morphology and hydrophobic properties of the aluminum alloy microstructures fabricated by two processing methods were observed respectively, and the hydrophobic mechanism was analyzed. The results show that the contact angle was effectively improved from 49° up to 158.4° in the vertical direction, and 146.7° in the parallel direction. The change of surface wettability from hydrophilic to hydrophobic was realized. By comparison, the micro-and nanostructure fabricated by WEDM had improved the hydrophobic stability of the aluminum alloy surface while enlarging the contact Angle, and the micro-milling groove structure further amplified the contact angle and greatly reduced the contact area of the water droplet, it was also observed that the drop took longer to completely spread on the sample after WEDM.

Triaxial Measurement Method for Analysis of Residual Stress after High Feed Milling by X-Ray Diffraction

NASA Astrophysics Data System (ADS)

Čuma, Matúš; Török, Jozef; Telišková, Monika

2016-12-01

Surface integrity is a broad term which includes various quality factors affecting the functional properties of parts. Residual stress is one of these factors. Machining generates residual stresses in the surface and subsurface layers of the structural elements. X-ray diffractometry is a non-destructive method applicable for the measurement of residual stresses in surface and subsurface layers of components. The article is focused on the non-destructive progressive method of triaxial measurement of residual stress after machining the surface of sample by high feed milling technology. Significance of triaxial measuring is the capability of measuring in different angles so it is possible to acquire stress tensor containing normal and shear stress components acting in the spot of measuring, using a Cartesian coordinate system.

Micro structrual characterization and analysis of ball milled silicon carbide

NASA Astrophysics Data System (ADS)

Madhusudan, B. M.; Raju, H. P.; Ghanaraja., S.

2018-04-01

Mechanical alloying has been one of the prominent methods of powder synthesis technique in solid state involving cyclic deformation, cold welding and fracturing of powder particles. Powder particles in this method are subjected to greater mechanical deformation due to the impact of ball-powder-ball and ball-powder-container collisions that occurs during mechanical alloying. Strain hardening and fracture of particles decreases the size of the particles and creates new surfaces. The objective of this Present work is to use ball milling of SiC powder for different duration of 5, 10, 15 and 20 hours by High energy planetary ball milling machine and to evaluate the effect of ball milling on SiC powder. Micro structural Studies using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and EDAX has been investigated.

Numerical approach in defining milling force taking into account curved cutting-edge of applied mills

NASA Astrophysics Data System (ADS)

Bondarenko, I. R.

2018-03-01

The paper tackles the task of applying the numerical approach to determine the cutting forces of carbon steel machining with curved cutting edge mill. To solve the abovementioned task the curved surface of the cutting edge was subject to step approximation, and the chips section was split into discrete elements. As a result, the cutting force was defined as the sum of elementary forces observed during the cut of every element. Comparison and analysis of calculations with regard to the proposed method and the method with Kienzle dependence showed its sufficient accuracy, which makes it possible to apply the method in practice.

Machinability of Stellite 6 hardfacing

NASA Astrophysics Data System (ADS)

Benghersallah, M.; Boulanouar, L.; Le Coz, G.; Devillez, A.; Dudzinski, D.

2010-06-01

This paper reports some experimental findings concerning the machinability at high cutting speed of nickel-base weld-deposited hardfacings for the manufacture of hot tooling. The forging work involves extreme impacts, forces, stresses and temperatures. Thus, mould dies must be extremely resistant. The aim of the project is to create a rapid prototyping process answering to forging conditions integrating a Stellite 6 hardfacing deposed PTA process. This study talks about the dry machining of the hardfacing, using a two tips machining tool and a high speed milling machine equipped by a power consumption recorder Wattpilote. The aim is to show the machinability of the hardfacing, measuring the power and the tip wear by optical microscope and white light interferometer, using different strategies and cutting conditions.

Vibration Damping Analysis of Lightweight Structures in Machine Tools

PubMed Central

Aggogeri, Francesco; Borboni, Alberto; Merlo, Angelo; Pellegrini, Nicola; Ricatto, Raffaele

2017-01-01

The dynamic behaviour of a machine tool (MT) directly influences the machining performance. The adoption of lightweight structures may reduce the effects of undesired vibrations and increase the workpiece quality. This paper aims to present and compare a set of hybrid materials that may be excellent candidates to fabricate the MT moving parts. The selected materials have high dynamic characteristics and capacity to dampen mechanical vibrations. In this way, starting from the kinematic model of a milling machine, this study evaluates a number of prototypes made of Al foam sandwiches (AFS), Al corrugated sandwiches (ACS) and composite materials reinforced by carbon fibres (CFRP). These prototypes represented the Z-axis ram of a commercial milling machine. The static and dynamical properties have been analysed by using both finite element (FE) simulations and experimental tests. The obtained results show that the proposed structures may be a valid alternative to the conventional materials of MT moving parts, increasing machining performance. In particular, the AFS prototype highlighted a damping ratio that is 20 times greater than a conventional ram (e.g., steel). Its application is particularly suitable to minimize unwanted oscillations during high-speed finishing operations. The results also show that the CFRP structure guarantees high stiffness with a weight reduced by 48.5%, suggesting effective applications in roughing operations, saving MT energy consumption. The ACS structure has a good trade-off between stiffness and damping and may represent a further alternative, if correctly evaluated. PMID:28772653

Fundamental investigation on influence of external heat on chip formation during thermal assisted machining

NASA Astrophysics Data System (ADS)

Alkali, A. U.; Ginta, T. L.; Abdulrani, A. M.; Elsiti, N. M.

2018-04-01

Various heat sources have been investigated by numerous researchers to reveal machinability benefits of thermally assisted machining (TAM) process. Fewer engineering materials have been tested. In the same vein, those researches continue to demonstrate effective performance of TAM in terms of bulk material removal rate, improved surface finish, prolong tool life and reduction of cutting forces among others. Experimental investigation on the strain-hardenability and flow stress of material removed with respect to increase in temperature in TAM has not been given attention in previous studies. This study investigated the pattern of chip morphology and segmentation giving close attention to influence of external heat source responsible for strain – hardenability of the material removed during TAM and dry machining at room temperature. Full immersion down cut milling was used throughout the machining conditions. Machining was conducted on AISI 316L using uncoated tungsten carbide end mill insert at varying cutting speeds (V) of 50, 79, and 100 m/min, and feed rates (f) of 0.15, 0.25, and 0.4 mm/tooth while the depth of cut was maintained at 0.2mm throughout the machining trials. The analyses of chip formation, segmentations and stain hardenability were carried out by using LMU light microscope, field emission microscopy and micro indentation. The study observed that build up edge is formed when a stagnation zone develops in front of tool tip which give rise to poor thermal gradient for conduction heat to be transferred within the bulk material during dry machining. This promotes varying strain – hardening of the material removed with evident high chips hardness and thickness, whereas TAM circumvents such impairment by softening the shear zone through local preheat.

High speed turning of compacted graphite iron using controlled modulation

NASA Astrophysics Data System (ADS)

Stalbaum, Tyler Paul

Compacted graphite iron (CGI) is a material which emerged as a candidate material to replace cast iron (CI) in the automotive industry for engine block castings. Its thermal and mechanical properties allow the CGI-based engines to operate at higher cylinder pressures and temperatures than CI-based engines, allowing for lower fuel emissions and increased fuel economy. However, these same properties together with the thermomechanical wear mode in the CGI-CBN system result in poor machinability and inhibit CGI from seeing wide spread use in the automotive industry. In industry, machining of CGI is done only at low speeds, less than V = 200 m/min, to avoid encountering rapid wear of the cutting tools during cutting. Studies have suggested intermittent cutting operations such as milling suffer less severe tool wear than continuous cutting. Furthermore, evidence that a hard sulfide layer which forms over the cutting edge in machining CI at high speeds is absent during machining CGI is a major factor in the difference in machinability of these material systems. The present study addresses both of these issues by modification to the conventional machining process to allow intermittent continuous cutting. The application of controlled modulation superimposed onto the cutting process -- modulation-assisted machining (MAM) -- is shown to be quite effective in reducing the wear of cubic boron nitride (CBN) tools when machining CGI at high machining speeds (> 500 m/min). The tool life is at least 20 times greater than found in conventional machining of CGI. This significant reduction in wear is a consequence of reduction in the severity of the tool-work contact conditions with MAM. The propensity for thermochemical wear of CBN is thus reduced. It is found that higher cutting speed (> 700 m/min) leads to lower tool wear with MAM. The MAM configuration employing feed-direction modulation appears feasible for implementation at high speeds and offers a solution to this challenging class of industrial machining applications. This study's approach is by series of high speed turning tests of CGI with CBN tools, comparing conventional machining to MAM for similar parameters otherwise, by tool wear measurements and machinability observations.

Effect of Bonding Agent Application Method on Titanium-Ceramic Bond Strength.

PubMed

Curtis, Joseph G; Dossett, Jon; Prihoda, Thomas J; Teixeira, Erica C

2015-07-01

Although milled titanium may be used as a substructure in fixed and implant prosthodontics, the application of the veneering porcelain presents particular challenges compared to traditional alloys. To address these challenges, some Ti ceramic systems incorporate the application of a bonding agent prior to the opaque layer. Vita Titankeramik's bonding agent is available as a powder, paste, and spray-on formulation. We examined the effect of these three application methods on the bond strength. Four titanium bars were milled from each of 11 wafers cut from grade II Ti using the Kavo Everest milling unit and a custom-designed milling toolpath. An experienced technician prepared the 25 × 3 × 0.5 mm(3) metal bars and applied bonding agent using one of three application methods, and then applied opaque, dentin, and enamel porcelains according to manufacturer's instructions to a 8 × 3 × 1 mm(3) porcelain. A control group received no bonding agent prior to porcelain application. The four groups (n = 11) were blindly tested for differences in bond strength using a universal testing machine in a three-point bend test configuration, based on ISO 9693-1:2012. The average (SD) bond strengths for the control, powder, paste, and spray-on groups, respectively, were: 24.8 (2.6), 24.6 (2.6), 25.3 (4.0), and 24.1 (3.9) MPa. One-way ANOVA and Tukey's multiple comparison tests were performed between all groups. There were no statistically significant differences among groups (p = 0.951). Titanium-porcelain bond strength was not affected by the use of a bonding agent or its application method when tested by ISO 9693-1 standard. © 2014 by the American College of Prosthodontists.

A defect-driven diagnostic method for machine tool spindles

PubMed Central

Vogl, Gregory W.; Donmez, M. Alkan

2016-01-01

Simple vibration-based metrics are, in many cases, insufficient to diagnose machine tool spindle condition. These metrics couple defect-based motion with spindle dynamics; diagnostics should be defect-driven. A new method and spindle condition estimation device (SCED) were developed to acquire data and to separate system dynamics from defect geometry. Based on this method, a spindle condition metric relying only on defect geometry is proposed. Application of the SCED on various milling and turning spindles shows that the new approach is robust for diagnosing the machine tool spindle condition. PMID:28065985

Substantiation of basic scheme of grain cleaning machine for preparation of agricultural crops seeds

NASA Astrophysics Data System (ADS)

Giyevskiy, A. M.; Orobinsky, V. I.; Tarasenko, A. P.; Chernyshov, A. V.; Kurilov, D. O.

2018-03-01

The article presents data on the feasibility of the concept of a high-efficiency seed cleaner with the consistent use of the air flow in aspiration and the multi-tier placement of the sorting grids in grating mills. As a result of modeling, the directions for further improvement of air-screen seed cleaning machines have been identified: an increase in the proportion of sorting grids in the mills up to 70 ... 80% and an increase in the speed of the air flow in the channel of the pre-filter cleaning up to 8.0 m / s. Experiments have established the competence of using mathematical modeling of airflow in the pneumatic system with the use of a finite-volume method for solving hydrodynamic equations for substantiating the basic parameters of the pneumatic system.

Design and Development of a Three-Component Force Sensor for Milling Process Monitoring

PubMed Central

Li, Yingxue; Zhao, Yulong; Fei, Jiyou; Qin, Yafei; Zhao, You; Cai, Anjiang; Gao, Song

2017-01-01

A strain-type three-component table dynamometer is presented in this paper, which reduces output errors produced by cutting forces imposed on the different milling positions of a workpiece. A sensor structure with eight parallel elastic beams is proposed, and sensitive regions and Wheastone measuring circuits are also designed in consideration of eliminating the influences of the eccentric forces. To evaluate the sensor decoupling performance, both of the static calibration and dynamic milling test were implemented in different positions of the workpiece. Static experiment results indicate that the maximal deviation between the measured forces and the standard inputs is 4.58%. Milling tests demonstrate that with same machining parameters, the differences of the measured forces between different milling positions derived by the developed sensor are no larger than 6.29%. In addition, the natural frequencies of the dynamometer are kept higher than 2585.5 Hz. All the measuring results show that as a strain-type dynamometer, the developed force sensor has an improved eccentric decoupling accuracy with natural frequencies not much decreased, which owns application potential in milling process monitoring. PMID:28441354

Machinability Study on Milling Kenaf Fiber Reinforced Plastic Composite Materials using Design of Experiments

NASA Astrophysics Data System (ADS)

Azmi, H.; Haron, C. H. C.; Ghani, J. A.; Suhaily, M.; Yuzairi, A. R.

2018-04-01

The surface roughness (Ra) and delamination factor (Fd) of a milled kenaf reinforced plastic composite materials are depending on the milling parameters (spindle speed, feed rate and depth of cut). Therefore, a study was carried out to investigate the relationship between the milling parameters and their effects on a kenaf reinforced plastic composite materials. The composite panels were fabricated using vacuum assisted resin transfer moulding (VARTM) method. A full factorial design of experiments was use as an initial step to screen the significance of the parameters on the defects using Analysis of Variance (ANOVA). If the curvature of the collected data shows significant, Response Surface Methodology (RSM) is then applied for obtaining a quadratic modelling equation that has more reliable in expressing the optimization. Thus, the objective of this research is obtaining an optimum setting of milling parameters and modelling equations to minimize the surface roughness (Ra) and delamination factor (Fd) of milled kenaf reinforced plastic composite materials. The spindle speed and feed rate contributed the most in affecting the surface roughness and the delamination factor of the kenaf composite materials.

JPRS Report, Science & Technology, USSR: Science & Technology Policy..

DTIC Science & Technology

1987-11-13

is necessary to have for comparison a gauge —"how much he should have done." How to surmount these difficulties is a theme for a separate study. Here...undergo in the shop complete machining, including the milling of complex surfaces, the boring of sockets, grooving, the drilling of holes, including deep...particularly machine building products. Thus, the sectorial ministries are implementing programs of the complete standardization and metrological

LOOKING WEST FROM THE TOP OF THE WATER TOWER AT ...

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

LOOKING WEST FROM THE TOP OF THE WATER TOWER AT ROOFTOPS OF INDUSTRIAL SHEDS. BUILDINGS IN THE FOREGROUND INCLUDE THE SHIPPING BAYS OF THE STRUCTURAL MILL AND MAIN ROLL SHOP. BUILDINGS IN THE MIDDLE GROUND INCLUDE PRESS SHOP NO. 2, CHIPPING YARD, BLACKSMITH SHOP, AND MACHINE SHOP NO. 1. THE TALLEST STRUCTURE IS THE VERTICAL FURNACE BUILDING, AND OPEN HEARTH NO. 5 IS IN THE EXTREME BACKGROUND. - U.S. Steel Homestead Works, Structural Mill, Along Monongahela River, Homestead, Allegheny County, PA

Achieving Small Structures in Thin NiTi Sheets for Medical Applications with Water Jet and Micro Machining: A Comparison

NASA Astrophysics Data System (ADS)

Frotscher, M.; Kahleyss, F.; Simon, T.; Biermann, D.; Eggeler, G.

2011-07-01

NiTi shape memory alloys (SMA) are used for a variety of applications including medical implants and tools as well as actuators, making use of their unique properties. However, due to the hardness and strength, in combination with the high elasticity of the material, the machining of components can be challenging. The most common machining techniques used today are laser cutting and electrical discharge machining (EDM). In this study, we report on the machining of small structures into binary NiTi sheets, applying alternative processing methods being well-established for other metallic materials. Our results indicate that water jet machining and micro milling can be used to machine delicate structures, even in very thin NiTi sheets. Further work is required to optimize the cut quality and the machining speed in order to increase the cost-effectiveness and to make both methods more competitive.

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

Hill, Mary Ann; Dombrowski, David E.; Clarke, Kester Diederik

U-10 wt. % Mo (U-10Mo) alloys are being developed as low enrichment monolithic fuel for the CONVERT program. Optimization of processing for the monolithic fuel is being pursued with the use of electrical discharge machining (EDM) under CONVERT HPRR WBS 1.2.4.5 Optimization of Coupon Preparation. The process is applicable to manufacturing experimental fuel plate specimens for the Mini-Plate-1 (MP-1) irradiation campaign. The benefits of EDM are reduced machining costs, ability to achieve higher tolerances, stress-free, burr-free surfaces eliminating the need for milling, and the ability to machine complex shapes. Kerf losses are much smaller with EDM (tenths of mm) comparedmore » to conventional machining (mm). Reliable repeatability is achievable with EDM due to its computer-generated machining programs.« less

Toolpath Strategy and Optimum Combination of Machining Parameter during Pocket Mill Process of Plastic Mold Steels Material

NASA Astrophysics Data System (ADS)

Wibowo, Y. T.; Baskoro, S. Y.; Manurung, V. A. T.

2018-02-01

Plastic based products spread all over the world in many aspects of life. The ability to substitute other materials is getting stronger and wider. The use of plastic materials increases and become unavoidable. Plastic based mass production requires injection process as well Mold. The milling process of plastic mold steel material was done using HSS End Mill cutting tool that is widely used in a small and medium enterprise for the reason of its ability to be re sharpened and relatively inexpensive. Study on the effect of the geometry tool states that it has an important effect on the quality improvement. Cutting speed, feed rate, depth of cut and radii are input parameters beside to the tool path strategy. This paper aims to investigate input parameter and cutting tools behaviors within some different tool path strategy. For the reason of experiments efficiency Taguchi method and ANOVA were used. Response studied is surface roughness and cutting behaviors. By achieving the expected quality, no more additional process is required. Finally, the optimal combination of machining parameters will deliver the expected roughness and of course totally reduced cutting time. However actually, SMEs do not optimally use this data for cost reduction.

Design of preventive maintenance system using the reliability engineering and maintenance value stream mapping methods in PT. XYZ

NASA Astrophysics Data System (ADS)

Sembiring, N.; Panjaitan, N.; Angelita, S.

2018-02-01

PT. XYZ is a company owned by non-governmental organizations engaged in the field of production of rubber processing becoming crumb rubber. Part of the production is supported by some of machines and interacting equipment to achieve optimal productivity. Types of the machine that are used in the production process are Conveyor Breaker, Breaker, Rolling Pin, Hammer Mill, Mill Roll, Conveyor, Shredder Crumb, and Dryer. Maintenance system in PT. XYZ is corrective maintenance i.e. repairing or replacing the engine components after the crash on the machine. Replacement of engine components on corrective maintenance causes the machine to stop operating during the production process is in progress. The result is in the loss of production time due to the operator must replace the damaged engine components. The loss of production time can impact on the production targets which were not reached and lead to high loss costs. The cost for all components is Rp. 4.088.514.505. This cost is really high just for maintaining a Mill Roll Machine. Therefore PT. XYZ is needed to do preventive maintenance i.e. scheduling engine components and improving maintenance efficiency. The used methods are Reliability Engineering and Maintenance Value Stream Mapping (MVSM). The needed data in this research are the interval of time damage to engine components, opportunity cost, labor cost, component cost, corrective repair time, preventive repair time, Mean Time To Opportunity (MTTO), Mean Time To Repair (MTTR), and Mean Time To Yield (MTTY). In this research, the critical components of Mill Roll machine are Spier, Bushing, Bearing, Coupling and Roll. Determination of damage distribution, reliability, MTTF, cost of failure, cost of preventive, current state map, and future state map are done so that the replacement time for each critical component with the lowest maintenance cost and preparation of Standard Operation Procedure (SOP) are developed. For the critical component that has been determined, the Spier component replacement time interval is 228 days with a reliability value of 0,503171, Bushing component is 240 days with reliability value of 0.36861, Bearing component is 202 days with reliability value of 0,503058, Coupling component is 247 days with reliability value of 0,50108 and Roll component is 301 days with reliability value of 0,373525. The results show that the cost decreases from Rp 300,688,114 to Rp 244,384,371 obtained from corrective maintenance to preventive maintenance. While maintenance efficiency increases with the application of preventive maintenance i.e. for Spier component from 54,0540541% to 74,07407%, Bushing component from 52,3809524% to 68,75%, Bearing component from 40% to 52,63158%, Coupling component from 60.9756098% to 71.42857%, and Roll components from 64.516129% to 74.7663551%.

Influence of tool speeds on dissimilar friction stir spot welding characteristics of bulk metallic glass/Mg alloy

NASA Astrophysics Data System (ADS)

Shin, Hyung-Seop; Jung, Yoon-Chul; Lee, Jin-Kyu

2012-08-01

A small-scale joining technique of dissimilar friction stir spot welding (FSSW) between bulk metallic glass and Mg alloy sheet has been tried using an apparatus which was devised with a CNC milling machine to give a precise control of tool speeds. The influence of tool speeds on the joining characteristics during FSSW was investigated. As a result, it was found that the rotation speed and plunge speed of a tool during FSSW significantly influenced the welding performance of dissimilar FSSW between bulk metallic glasses and Mg alloy.

Development turbine blade for ultramicro hydro power generation by 3D printer system

NASA Astrophysics Data System (ADS)

Kamimura, T.; Itoh, H.; Sugiura, K.

2017-11-01

We have developed micro generation system for effective use of unutilized energy and the spread of a self-controlled dispersion energy supply system. The turbine blade was designed for achieving high performance by special shape. The turbine type was called quasi-Peace turbine type. Turbine with a diameter of 30cm is made of metal, it was created by the 5-axis milling machine. The experimental apparatus was fabricated by the 3D printer. An experiment was carried out in the scale down model. The specific speed of this turbine was much lower than that of existing turbines.

Surface Finish and Residual Stresses Induced by Orthogonal Dry Machining of AA7075-T651

PubMed Central

Jomaa, Walid; Songmene, Victor; Bocher, Philippe

2014-01-01

The surface finish was extensively studied in usual machining processes (turning, milling, and drilling). For these processes, the surface finish is strongly influenced by the cutting feed and the tool nose radius. However, a basic understanding of tool/surface finish interaction and residual stress generation has been lacking. This paper aims to investigate the surface finish and residual stresses under the orthogonal cutting since it can provide this information by avoiding the effect of the tool nose radius. The orthogonal machining of AA7075-T651 alloy through a series of cutting experiments was performed under dry conditions. Surface finish was studied using height and amplitude distribution roughness parameters. SEM and EDS were used to analyze surface damage and built-up edge (BUE) formation. An analysis of the surface topography showed that the surface roughness was sensitive to changes in cutting parameters. It was found that the formation of BUE and the interaction between the tool edge and the iron-rich intermetallic particles play a determinant role in controlling the surface finish during dry orthogonal machining of the AA7075-T651 alloy. Hoop stress was predominantly compressive on the surface and tended to be tensile with increased cutting speed. The reverse occurred for the surface axial stress. The smaller the cutting feed, the greater is the effect of cutting speed on both axial and hoop stresses. By controlling the cutting speed and feed, it is possible to generate a benchmark residual stress state and good surface finish using dry machining. PMID:28788534

Monitoring of laser material processing using machine integrated low-coherence interferometry

NASA Astrophysics Data System (ADS)

Kunze, Rouwen; König, Niels; Schmitt, Robert

2017-06-01

Laser material processing has become an indispensable tool in modern production. With the availability of high power pico- and femtosecond laser sources, laser material processing is advancing into applications, which demand for highest accuracies such as laser micro milling or laser drilling. In order to enable narrow tolerance windows, a closedloop monitoring of the geometrical properties of the processed work piece is essential for achieving a robust manufacturing process. Low coherence interferometry (LCI) is a high-precision measuring principle well-known from surface metrology. In recent years, we demonstrated successful integrations of LCI into several different laser material processing methods. Within this paper, we give an overview about the different machine integration strategies, that always aim at a complete and ideally telecentric integration of the measurement device into the existing beam path of the processing laser. Thus, highly accurate depth measurements within machine coordinates and a subsequent process control and quality assurance are possible. First products using this principle have already found its way to the market, which underlines the potential of this technology for the monitoring of laser material processing.

A post-processing study on aluminum surface by fiber laser: Removing face milling patterns

NASA Astrophysics Data System (ADS)

Kayahan, Ersin

2018-05-01

The face milling process of the metal surface is a well-known machining process of using rotary cutters to remove material from a workpiece. Flat metal surfaces can be produced by a face milling process. However, in practice, visible, traced marks following the motion of points on the cutter's face are usually apparent. In this study, it was shown that milled patterns can be removed by means of 20 W fiber laser on the aluminum surface (AA7075). Experimental results also showed that roughened and hydrophobic surface can be produced with optimized laser parameters. It is a new approach to remove the patterns from the metal surface and can be explained through roughening by re-melting instead of ablation. The new method is a strong candidate to replace sandblasting the metal surface. It is also cheap and environmentally friendly.

Modelling of teeth of a gear transmission for modern manufacturing technologies

NASA Astrophysics Data System (ADS)

Monica, Z.; Banaś, W.; Ćwikla, G.; Topolska, S.

2017-08-01

The technological process of manufacturing of gear wheels is influenced by many factors. It is designated depending on the type of material from which the gear is to be produced, its heat treatment parameters, the required accuracy, the geometrical form and the modifications of the tooth. Therefor the parameters selection process is not easy and moreover it is unambiguous. Another important stage of the technological process is the selection of appropriate tools to properly machine teeth in the operations of both roughing and finishing. In the presented work the focus is put first of all on modern production methods of gears using technologically advanced instruments in comparison with conventional tools. Conventional processing tools such as gear hobbing cutters or Fellows gear-shaper cutters are used from the beginning of the machines for the production of gear wheels. With the development of technology and the creation of CNC machines designated for machining of gears wheel it was also developed the manufacturing technology as well as the design knowledge concerning the technological tools. Leading manufacturers of cutting tools extended the range of tools designated for machining of gears on the so-called hobbing cutters with inserted cemented carbide tips. The same have be introduced to Fellows gear-shaper cutters. The results of tests show that is advantaged to use hobbing cutters with inserted cemented carbide tips for milling gear wheels with a high number of teeth, where the time gains are very high, in relation to the use of conventional milling cutters.

Optimization design and analysis of the pavement planer scraper structure

NASA Astrophysics Data System (ADS)

Fang, Yuanbin; Sha, Hongwei; Yuan, Dajun; Xie, Xiaobing; Yang, Shibo

2018-03-01

By LS-DYNA, it establishes the finite element model of road milling machine scraper, and analyses the dynamic simulation. Through the optimization of the scraper structure and scraper angle, obtain the optimal structure of milling machine scraper. At the same time, the simulation results are verified. The results show that the scraper structure is improved that cemented carbide is located in the front part of the scraper substrate. Compared with the working resistance before improvement, it tends to be gentle and the peak value is smaller. The cutting front angle and the cutting back angle are optimized. The cutting front angle is 6 degrees and the cutting back angle is 9 degrees. The resultant of forces which contains the working resistance and the impact force is the least. It proves accuracy of the simulation results and provides guidance for further optimization work.

Tool Condition Monitoring and Remaining Useful Life Prognostic Based on a Wireless Sensor in Dry Milling Operations.

PubMed

Zhang, Cunji; Yao, Xifan; Zhang, Jianming; Jin, Hong

2016-05-31

Tool breakage causes losses of surface polishing and dimensional accuracy for machined part, or possible damage to a workpiece or machine. Tool Condition Monitoring (TCM) is considerably vital in the manufacturing industry. In this paper, an indirect TCM approach is introduced with a wireless triaxial accelerometer. The vibrations in the three vertical directions (x, y and z) are acquired during milling operations, and the raw signals are de-noised by wavelet analysis. These features of de-noised signals are extracted in the time, frequency and time-frequency domains. The key features are selected based on Pearson's Correlation Coefficient (PCC). The Neuro-Fuzzy Network (NFN) is adopted to predict the tool wear and Remaining Useful Life (RUL). In comparison with Back Propagation Neural Network (BPNN) and Radial Basis Function Network (RBFN), the results show that the NFN has the best performance in the prediction of tool wear and RUL.

Optimization of Parameters for Manufacture Nanopowder Bioceramics at Machine Pulverisette 6 by Taguchi and ANOVA Method

NASA Astrophysics Data System (ADS)

Van Hoten, Hendri; Gunawarman; Mulyadi, Ismet Hari; Kurniawan Mainil, Afdhal; Putra, Bismantoloa dan

2018-02-01

This research is about manufacture nanopowder Bioceramics from local materials used Ball Milling for biomedical applications. Source materials for the manufacture of medicines are plants, animal tissues, microbial structures and engineering biomaterial. The form of raw material medicines is a powder before mixed. In the case of medicines, research is to find sources of biomedical materials that will be in the nanoscale powders can be used as raw material for medicine. One of the biomedical materials that can be used as raw material for medicine is of the type of bioceramics is chicken eggshells. This research will develop methods for manufacture nanopowder material from chicken eggshells with Ball Milling using the Taguchi method and ANOVA. Eggshell milled using a variation of Milling rate on 150, 200 and 250 rpm, the time variation of 1, 2 and 3 hours and variations the grinding balls to eggshell powder weight ratio (BPR) 1: 6, 1: 8, 1: 10. Before milled with Ball Milling crushed eggshells in advance and calcinate to a temperature of 900°C. After the milled material characterization of the fine powder of eggshell using SEM to see its size. The result of this research is optimum parameter of Taguchi Design analysis that is 250 rpm milling rate, 3 hours milling time and BPR is 1: 6 with the average eggshell powder size is 1.305 μm. Milling speed, milling time and ball to powder weight of ratio have contribution successively equal to 60.82%, 30.76% and 6.64% by error equal to 1.78%.

Measurement of W + bb and a search for MSSM Higgs bosons with the CMS detector at the LHC

NASA Astrophysics Data System (ADS)

O'Connor, Alexander Pinpin

Tooling used to cure composite laminates in the aerospace and automotive industries must provide a dimensionally stable geometry throughout the thermal cycle applied during the part curing process. This requires that the Coefficient of Thermal Expansion (CTE) of the tooling materials match that of the composite being cured. The traditional tooling material for production applications is a nickel alloy. Poor machinability and high material costs increase the expense of metallic tooling made from nickel alloys such as 'Invar 36' or 'Invar 42'. Currently, metallic tooling is unable to meet the needs of applications requiring rapid affordable tooling solutions. In applications where the tooling is not required to have the durability provided by metals, such as for small area repair, an opportunity exists for non-metallic tooling materials like graphite, carbon foams, composites, or ceramics and machinable glasses. Nevertheless, efficient machining of brittle, non-metallic materials is challenging due to low ductility, porosity, and high hardness. The machining of a layup tool comprises a large portion of the final cost. Achieving maximum process economy requires optimization of the machining process in the given tooling material. Therefore, machinability of the tooling material is a critical aspect of the overall cost of the tool. In this work, three commercially available, brittle/porous, non-metallic candidate tooling materials were selected, namely: (AAC) Autoclaved Aerated Concrete, CB1100 ceramic block and Cfoam carbon foam. Machining tests were conducted in order to evaluate the machinability of these materials using end milling. Chip formation, cutting forces, cutting tool wear, machining induced damage, surface quality and surface integrity were investigated using High Speed Steel (HSS), carbide, diamond abrasive and Polycrystalline Diamond (PCD) cutting tools. Cutting forces were found to be random in magnitude, which was a result of material porosity. The abrasive nature of Cfoam produced rapid tool wear when using HSS and PCD type cutting tools. However, tool wear was not significant in AAC or CB1100 regardless of the type of cutting edge. Machining induced damage was observed in the form of macro-scale chipping and fracture in combination with micro-scale cracking. Transverse rupture test results revealed significant reductions in residual strength and damage tolerance in CB1100. In contrast, AAC and Cfoam showed no correlation between machining induced damage and a reduction in surface integrity. Cutting forces in machining were modeled for all materials. Cutting force regression models were developed based on Design of Experiment and Analysis of Variance. A mechanistic cutting force model was proposed based upon conventional end milling force models and statistical distributions of material porosity. In order to validate the model, predicted cutting forces were compared to experimental results. Predicted cutting forces agreed well with experimental measurements. Furthermore, over the range of cutting conditions tested, the proposed model was shown to have comparable predictive accuracy to empirically produced regression models; greatly reducing the number of cutting tests required to simulate cutting forces. Further, this work demonstrates a key adaptation of metallic cutting force models to brittle porous material; a vital step in the research into the machining of these materials using end milling.

Surface morphology study in high speed milling of soda lime glass

NASA Astrophysics Data System (ADS)

Konneh, Mohamed; Bagum, Mst. Nasima; Ali, Mohammad Yeakub; Amin, A. K. M. Nurul

2018-05-01

Soda lime glass has a wide range of applications in optical, bio-medical and semi-conductor industries. It is undeniably a challenging task to produce micro finish surface on an amorphous brittle solid like soda lime glass due to its low fracture toughness. In order to obtain such a finish surface, ductile machining has been exploited, as this usually cause's plastic flow which control crack propagation. At sub-micro scale cutting parameters, researchers achieved nano finish surface in micro milling operation using coated tool. However it is possible to enhance the rate of material removal (RMR) of soda lime glass at flexible cutting condition. High speed cutting at micro meter level, extend of thermal softening might be prominent than the strain gradient strengthening. The purpose of this study was to explore the effects of high cutting speed end milling parameters on the surface texture of soda lime glass using uncoated carbide tool. The spindle speed, depth of cut and feed rate were varied from 20,000 to 40,000 rpm, 10 to 30 mm/min and 30 to 50 µm respectively. Mathematical model of roughness has been developed using Response Surface Methodology (RSM). Experimental verification confirmed that surface roughness (Ra) 0.38 µm is possible to achieve at increased RMR, 4.71 mm3/min.

Machining Chatter Analysis for High Speed Milling Operations

NASA Astrophysics Data System (ADS)

Sekar, M.; Kantharaj, I.; Amit Siddhappa, Savale

2017-10-01

Chatter in high speed milling is characterized by time delay differential equations (DDE). Since closed form solution exists only for simple cases, the governing non-linear DDEs of chatter problems are solved by various numerical methods. Custom codes to solve DDEs are tedious to build, implement and not error free and robust. On the other hand, software packages provide solution to DDEs, however they are not straight forward to implement. In this paper an easy way to solve DDE of chatter in milling is proposed and implemented with MATLAB. Time domain solution permits the study and model of non-linear effects of chatter vibration with ease. Time domain results are presented for various stable and unstable conditions of cut and compared with stability lobe diagrams.

ROMI-RIP: Rough mill rip-first simulator. Forest Service general technical report (Final)

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

Thomas, R.E.

1995-07-01

The ROugh Mill Rip-First Simulator (ROMI-RIP) is a computer software package that simulates the gang-ripping of lumber. ROMI-RIP was designed to closely simulate current machines and industrial practice. This simulator allows the user to perform `what if` analyses on various gang-rip-first rough mill operations with fixed, floating outer blade and all-movable blade arbors. ROMI-RIP accepts cutting bills with up to 300 different part sizes. Plots of processed boards are easily viewed or printed. Detailed summaries of processing steps (number of rips and crosscuts) and yields (single boards or entire board files) can also be viewed of printed. ROMI-RIP requires IBMmore » personal computers with 80286 of higher processors.« less

Fuzzy Petri nets to model vision system decisions within a flexible manufacturing system

NASA Astrophysics Data System (ADS)

Hanna, Moheb M.; Buck, A. A.; Smith, R.

1994-10-01

The paper presents a Petri net approach to modelling, monitoring and control of the behavior of an FMS cell. The FMS cell described comprises a pick and place robot, vision system, CNC-milling machine and 3 conveyors. The work illustrates how the block diagrams in a hierarchical structure can be used to describe events at different levels of abstraction. It focuses on Fuzzy Petri nets (Fuzzy logic with Petri nets) including an artificial neural network (Fuzzy Neural Petri nets) to model and control vision system decisions and robot sequences within an FMS cell. This methodology can be used as a graphical modelling tool to monitor and control the imprecise, vague and uncertain situations, and determine the quality of the output product of an FMS cell.

Quantitative Evaluation of Heavy Duty Machine Tools Remanufacturing Based on Modified Catastrophe Progression Method

NASA Astrophysics Data System (ADS)

shunhe, Li; jianhua, Rao; lin, Gui; weimin, Zhang; degang, Liu

2017-11-01

The result of remanufacturing evaluation is the basis for judging whether the heavy duty machine tool can remanufacture in the EOL stage of the machine tool lifecycle management.The objectivity and accuracy of evaluation is the key to the evaluation method.In this paper, the catastrophe progression method is introduced into the quantitative evaluation of heavy duty machine tools’ remanufacturing,and the results are modified by the comprehensive adjustment method,which makes the evaluation results accord with the standard of human conventional thinking.Using the catastrophe progression method to establish the heavy duty machine tools’ quantitative evaluation model,to evaluate the retired TK6916 type CNC floor milling-boring machine’s remanufacturing.The evaluation process is simple,high quantification,the result is objective.

Orion Heat Shield

NASA Image and Video Library

2015-03-09

THE ORION HEAT SHIELD THAT SUCCESSFULLY SURVIVED A HIGH-VELOCITY REENTRY DURING ITS DEC. 5 FLIGHT TEST, IS CONTINUING ITS JOURNEY, NOW AT MARSHALL. IT ARRIVED ON MONDAY, MARCH 9 AND WILL BE INSTALLED IN THE BUILDING 4705 7-AXIS MILLING AND MACHINING CENTER.

Wear of carbide inserts with complex surface treatment when milling nickel alloy

NASA Astrophysics Data System (ADS)

Fedorov, Sergey; Swe, Min Htet; Kapitanov, Alexey; Egorov, Sergey

2018-03-01

One of the effective ways of strengthening hard alloys is the creating structure layers on their surface with the gradient distribution of physical and mechanical properties between the wear-resistant coating and the base material. The article discusses the influence of the near-surface layer which is modified by low-energy high-current electron-beam alloying and the upper anti-friction layer in a multi-component coating on the wear mechanism of the replaceable multifaceted plates in the dry milling of the difficult to machine nickel alloys.

DETAIL VIEW OF ARRASTRA, LOOKING SOUTHEAST. THIS OLD TECHNOLOGY IS ...

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

DETAIL VIEW OF ARRASTRA, LOOKING SOUTHEAST. THIS OLD TECHNOLOGY IS AN ANACHRONISM OF THIS MILL. ORE WAS DUMPED INTO THE STONE LINED TROUGH. AS THE ARRASTRA TURNED LARGE STONES CONNECTED TO THE FOUR ARMS WERE DRAGGED AROUND OVER THE ORE TO CRUSH IT. IT IS CLEAR THAT THIS ARRASTRA WAS POWERED BY MACHINE THOUGH IT IS UNCLEAR EXACTLY HOW IT WAS POWERED. THE WHITE PINE TALC MINE OPENING IS SEEN IN THE DISTANCE AT THE CENTER LEFT EDGE. - Gold Hill Mill, Warm Spring Canyon Road, Death Valley Junction, Inyo County, CA

Application of reverse engineering in the production of individual dental abutments.

NASA Astrophysics Data System (ADS)

Yunusov, A. V.; Kashapov, R. N.; Kashapov, L. N.; Statsenko, E. O.

2017-09-01

The purpose of the research is to develop a method of manufacturing individual dental abutments for a variety of dental implants. System of industrial X-ray microtomography Phoenix V|tome|X S 240 has been applied for creation of highly accurate model of the dental abutment. Scanning of dental abutment and the optimization of model was produced. The program of milling the individual abutment with a standard conical neck of hexagon was produced for the five-axis milling machine imes - icore 450i from the materials titanium and zirconium oxide.

2. LOOKING WEST FROM THE TOP OF THE WATER TOWER ...

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

2. LOOKING WEST FROM THE TOP OF THE WATER TOWER AT ROOFTOPS OF INDUSTRIAL SHEDS. BUILDINGS IN THE FOREGROUND INCLUDE THE SHIPPING BAYS OF THE STRUCTURAL MILL AND MAIN ROLL SHOP. BUILDINGS IN THE MIDDLE GROUND INCLUDE PRESS SHOP No. 2, CHIPPING YARD, BLACKSMITH SHOP, AND MACHINE SHOP No. 1. THE TALLEST STRUCTURE IS THE VERTICAL FURNACE BUILDING, AND OPEN HEARTH No. 5 IS IN THE EXTREME BACKGROUND. Jet Lowe, Photographer, 1989. - U.S. Steel Homestead Works, Structural Mill, Along Monongahela River, Homestead, Allegheny County, PA

Development and Implementation of a Simplified Tool Measuring System

NASA Astrophysics Data System (ADS)

Chen, Jenn-Yih; Lee, Bean-Yin; Lee, Kuang-Chyi; Chen, Zhao-Kai

2010-01-01

This paper presents a simplified system for measuring geometric profiles of end mills. Firstly, a CCD camera was used to capture images of cutting tools. Then, an image acquisition card with the encoding function was adopted to convert the source of image into an USB port of a PC, and the image could be shown on a monitor. In addition, two linear scales were mounted on the X-Y table for positioning and measuring purposes. The signals of the linear scales were transmitted into a 4-axis quadrature encoder with 4-channel counter card for position monitoring. The C++ Builder was utilized for designing the user friendly human machine interface of the measuring system of tools. There is a cross line on the image of the interface to show a coordinate for the position measurement. Finally, a well-known tool measuring and inspection machine was employed for the measuring standard. This study compares the difference of the measuring results by using the machine and the proposed system. Experimental results show that the percentage of measuring error is acceptable for some geometric parameters of the square or ball nose end mills. Therefore, the results demonstrate the effectiveness of the presented approach.

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

29 CFR 785.24 - Principles noted in Portal-to-Portal Bulletin.

Code of Federal Regulations, 2010 CFR

2010-07-01

... his machine, or install a new cutting tool. Such activities are an integral part of the principal activity, and are included within such term. (2) In the case of a garment worker in a textile mill, who is...

29 CFR 570.59 - Occupations involved in the operation of power-driven metal forming, punching, and shearing...

Code of Federal Regulations, 2011 CFR

2011-07-01

... beading, straightening, corrugating, flanging, or bending rolls; and hot or cold rolling mills. (ii) All... area between the dies; power presses; and plate punches. (iii) All bending machines, such as apron...

Safety issues in high speed machining

NASA Astrophysics Data System (ADS)

1994-05-01

There are several risks related to High-Speed Milling, but they have not been systematically determined or studied so far. Increased loads by high centrifugal forces may result in dramatic hazards. Flying tools or fragments from a tool with high kinetic energy may damage surrounding people, machines and devices. In the project, mechanical risks were evaluated, theoretic values for kinetic energies of rotating tools were calculated, possible damages of the flying objects were determined and terms to eliminate the risks were considered. The noise levels of the High-Speed Machining center owned by the Helsinki University of Technology (HUT) and the Technical Research Center of Finland (VTT) in practical machining situation were measured and the results were compared to those after basic preventive measures were taken.

Main Oxidizer Valve Design

NASA Technical Reports Server (NTRS)

Addona, Brad; Eddleman, David

2015-01-01

A developmental Main Oxidizer Valve (MOV) was designed by NASA-MSFC using additive manufacturing processes. The MOV is a pneumatically actuated poppet valve to control the flow of liquid oxygen to an engine's injector. A compression spring is used to return the valve to the closed state when pneumatic pressure is removed from the valve. The valve internal parts are cylindrical in shape, which lends itself to traditional lathe and milling operations. However, the valve body represents a complicated shape and contains the majority of the mass of the valve. Additive manufacturing techniques were used to produce a part that optimized mass and allowed for design features not practical with traditional machining processes.

Rare etiological factor of maxillofacial injury: Case series seen and managed in a tertiary referral centre

PubMed Central

Braimah, Ramat Oyebunmi; Ibikunle, Adebayo Aremu; Taiwo, Abdurrazaq Olanrewaju

2016-01-01

Entanglement injury from local milling/grinding machine with a conveyor belt is a rare etiology of maxillofacial injuries. While there is abundant literature on industrial cause of trauma, entanglement injury as a mechanism has not been reported in the literature. We present two cases of maxillofacial injury secondary to entanglement of the loose apparel into the conveyor belt of the local grinding machine. The community should be aware of this rare cause of trauma, and adequate protection of children using these facilities should be enforced. One of such measure is to provide physical barriers to guard against these machines. PMID:27162440

Rare etiological factor of maxillofacial injury: Case series seen and managed in a tertiary referral centre.

PubMed

Braimah, Ramat Oyebunmi; Ibikunle, Adebayo Aremu; Taiwo, Abdurrazaq Olanrewaju

2016-01-01

Entanglement injury from local milling/grinding machine with a conveyor belt is a rare etiology of maxillofacial injuries. While there is abundant literature on industrial cause of trauma, entanglement injury as a mechanism has not been reported in the literature. We present two cases of maxillofacial injury secondary to entanglement of the loose apparel into the conveyor belt of the local grinding machine. The community should be aware of this rare cause of trauma, and adequate protection of children using these facilities should be enforced. One of such measure is to provide physical barriers to guard against these machines.

18. VIEW OF BALES OF CEDAR TOW (CEDAR SHAVING WITH ...

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

18. VIEW OF BALES OF CEDAR TOW (CEDAR SHAVING WITH SAWDUST TUMBLED OUT) SOLD FOR GARDEN AND ANIMAL BEDDING, AND OTHER AGRICULTURAL USES; TUMBLER IS CYLINDRICAL MACHINE TO LEFT - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

3. Interior view of section of warehouse building now used ...

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

3. Interior view of section of warehouse building now used as an opening room. 'Unifloc' machine manufactured by Rieter opens and blends cotton from several bales before processing. - Dixie Cotton Mill, Warehouses, 710 Greenville Street, La Grange, Troup County, GA

2. AERIAL VIEW LOOKING WEST SOUTHWEST SHOWING DOLPHIN MANUFACTURING CO., ...

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

2. AERIAL VIEW LOOKING WEST SOUTHWEST SHOWING DOLPHIN MANUFACTURING CO., BARBOUR FLAX SPINNING CO. -- SPRUCE ST. MILL, ROGERS LOCOMOTIVE AND MACHINE WORKS -- MILLWRIGHT SHOP AND FITTING SHOP. - Great Falls S. U. M. Historic District, Oliver Street, Paterson, Passaic County, NJ

Animal welfare: what has changed in the past 50 years?

PubMed

2014-07-12

The 3(rd) CABI symposium on animal welfare and behaviour was held on June 11, and featured a range of talks on 'animals as machines'. The symposium marked the 50(th) anniversary of the publication of the book 'Animal Machines' by Ruth Harrison. The book decried the conditions experienced at that time by many animals kept in intensive farming systems, and the speakers at the symposium discussed how far animal welfare had come since its publication. Georgina Mills reports. British Veterinary Association.

Engineer Design of a Mono-Mooring System.

DTIC Science & Technology

1966-01-01

swivels . When asked whether the bogie rails were machined by a large radius boring mill , Mr. Coombe indicated that these rails are rolled then V welded...lifted aboard the transp ort vessel , the disposi- tion of the various system compo- nents shall be as follows: 1. Buoy shall be complete , with...tugboat , equipped with towing winch or pow9r capstan , LOA 110 ’ — 120’, twin screw; BHP-l000 minimum . 7. It has been assumed that weld- ing machines

Study on residual stresses in ultrasonic torsional vibration assisted micro-milling

NASA Astrophysics Data System (ADS)

Lu, Zesheng; Hu, Haijun; Sun, Yazhou; Sun, Qing

2010-10-01

It is well known that machining induced residual stresses can seriously affect the dimensional accuracy, corrosion and wear resistance, etc., and further influence the longevity and reliability of Micro-Optical Components (MOC). In Ultrasonic Torsional Vibration Assisted Micro-milling (UTVAM), cutting parameters, vibration parameters, mill cutter parameters, the status of wear length of tool flank are the main factors which affect residual stresses. A 2D model of UTVAM was established with FE analysis software ABAQUS. Johnson-Cook's flow stress model and shear failure principle are used as the workpiece material model and failure principle, while friction between tool and workpiece uses modified Coulomb's law whose sliding friction area is combined with sticking friction. By means of FEA, the influence rules of cutting parameters, vibration parameters, mill cutter parameters, the status of wear length of tool flank on residual stresses are obtained, which provides a basis for choosing optimal process parameters and improving the longevity and reliability of MOC.

Application of variable teeth pitch face mill as chatter suppression method for non-rigid technological system

NASA Astrophysics Data System (ADS)

Svinin, V. M.; Savilov, A. V.

2018-03-01

The article describes the results of experimental studies on the effects of variation type for variable teeth pitches on low-rigidity workpiece chatter suppression efficiency in a feed direction and in a direction of the normal to the machined surface. Mill operation performance was identified by comparing the amplitudes of dominant chatter harmonics using constant and variable teeth pitches. The following variable pitch formation variants were studied: alternative, linear rising, and linear rising falling. The angle difference of adjacent teeth pitches ranged from 0 to 10°, from 5 to 8° and from 5 to 10° with interval of 1°. The experiments showed that for all variants, machining dynamics performance resulted from the difference of adjacent pitches corresponding to a half the chatter wavelength along the cutting surface. The alternative nature of a variable teeth pitch is most efficient as it almost completely suppresses the chatters. Theoretical explanations of the results are presented

Tool Condition Monitoring and Remaining Useful Life Prognostic Based on a Wireless Sensor in Dry Milling Operations

PubMed Central

Zhang, Cunji; Yao, Xifan; Zhang, Jianming; Jin, Hong

2016-01-01

Tool breakage causes losses of surface polishing and dimensional accuracy for machined part, or possible damage to a workpiece or machine. Tool Condition Monitoring (TCM) is considerably vital in the manufacturing industry. In this paper, an indirect TCM approach is introduced with a wireless triaxial accelerometer. The vibrations in the three vertical directions (x, y and z) are acquired during milling operations, and the raw signals are de-noised by wavelet analysis. These features of de-noised signals are extracted in the time, frequency and time–frequency domains. The key features are selected based on Pearson’s Correlation Coefficient (PCC). The Neuro-Fuzzy Network (NFN) is adopted to predict the tool wear and Remaining Useful Life (RUL). In comparison with Back Propagation Neural Network (BPNN) and Radial Basis Function Network (RBFN), the results show that the NFN has the best performance in the prediction of tool wear and RUL. PMID:27258277

Production of rotational parts in small-series and computer-aided planning of its production engineering

NASA Astrophysics Data System (ADS)

Dudas, Illes; Berta, Miklos; Cser, Istvan

1998-12-01

Up-to-date manufacturing equipments of production of rotational parts in small series are lathe-centers and CNC grinding machines with high concentration of manufacturing operations. By the use of these machine tools it can be produced parts with requirements of increased accuracy and surface quality. In the lathe centers, which contain the manufacturing procedures of lathes using stationary tools and of drilling-milling machine tools using rotational tools, non-rotational surfaces of rotational parts can also be produced. The high concentration of manufacturing operations makes necessary the planning and programing of the measuring, monitoring and quality control into the technological process during manufacturing operation. In this way, taking into consideration the technological possibilities of lathe canters, the scope of computer aided technological planning duties significantly increases. It is trivial requirement to give only once the descriptions of the prefabricated parts and ready made parts. Starting taking into account these careful considerations we have been developing the planning system of technology of body of revolution on the base of GTIPROG/EC system which useful for programming of lathe centers. Out paper deals with the results of development and the occurring problems.

27. The AssortingRoom in the paper mill. After the paper ...

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

27. The Assorting-Room in the paper mill. After the paper has been calendered, the big rolls are put into a cutting-machine that cuts the continuous roll into sheets of the desired size. These are then examined, sheet by sheet, by the women shown in the picture. All perfect shoes are put into one pile and the imperfect ones are placed in another pile. The perfect sheets are then ready, after trimming, for the presses of the National Geographic. (p.241.) - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

Optimizing the milling characteristics of Al-SiC particulate composites

NASA Astrophysics Data System (ADS)

Karthikeyan, R.; Raghukandan, K.; Naagarazan, R. S.; Pai, B. C.

2000-12-01

The present investigation focuses on the face milling characteristics of LM25Al-SiC particulate composites produced through stir casting. Experiments were conducted according to an L27 orthogonal array and mathematical models were developed for such machining characteristics as flank wear, specific energy and surface roughness whose adequacy was checked. The insignificant effects present in the models were eliminated using a t-test. Goal programming was employed to optimize the cutting conditions by considering such primary objectives as maximizing the metal removal rate and minimizing tool wear, specific energy and surface roughness.

Near-Net Shape Fabrication Using Low-Cost Titanium Alloy Powders

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

Dr. David M. Bowden; Dr. William H. Peter

2012-03-31

The use of titanium in commercial aircraft production has risen steadily over the last half century. The aerospace industry currently accounts for 58% of the domestic titanium market. The Kroll process, which has been used for over 50 years to produce titanium metal from its mineral form, consumes large quantities of energy. And, methods used to convert the titanium sponge output of the Kroll process into useful mill products also require significant energy resources. These traditional approaches result in product forms that are very expensive, have long lead times of up to a year or more, and require costly operationsmore » to fabricate finished parts. Given the increasing role of titanium in commercial aircraft, new titanium technologies are needed to create a more sustainable manufacturing strategy that consumes less energy, requires less material, and significantly reduces material and fabrication costs. A number of emerging processes are under development which could lead to a breakthrough in extraction technology. Several of these processes produce titanium alloy powder as a product. The availability of low-cost titanium powders may in turn enable a more efficient approach to the manufacture of titanium components using powder metallurgical processing. The objective of this project was to define energy-efficient strategies for manufacturing large-scale titanium structures using these low-cost powders as the starting material. Strategies include approaches to powder consolidation to achieve fully dense mill products, and joining technologies such as friction and laser welding to combine those mill products into near net shape (NNS) preforms for machining. The near net shape approach reduces material and machining requirements providing for improved affordability of titanium structures. Energy and cost modeling was used to define those approaches that offer the largest energy savings together with the economic benefits needed to drive implementation. Technical feasibility studies were performed to identify the most viable approaches to NNS preform fabrication using basic powder metallurgy mill product forms as the building blocks and advanced joining techniques including fusion and solid state joining to assemble these building blocks into efficient machining performs.« less

Deployment and evaluation of a dual-sensor autofocusing method for on-machine measurement of patterns of small holes on freeform surfaces.

PubMed

Chen, Xiaomei; Longstaff, Andrew; Fletcher, Simon; Myers, Alan

2014-04-01

This paper presents and evaluates an active dual-sensor autofocusing system that combines an optical vision sensor and a tactile probe for autofocusing on arrays of small holes on freeform surfaces. The system has been tested on a two-axis test rig and then integrated onto a three-axis computer numerical control (CNC) milling machine, where the aim is to rapidly and controllably measure the hole position errors while the part is still on the machine. The principle of operation is for the tactile probe to locate the nominal positions of holes, and the optical vision sensor follows to focus and capture the images of the holes. The images are then processed to provide hole position measurement. In this paper, the autofocusing deviations are analyzed. First, the deviations caused by the geometric errors of the axes on which the dual-sensor unit is deployed are estimated to be 11 μm when deployed on a test rig and 7 μm on the CNC machine tool. Subsequently, the autofocusing deviations caused by the interaction of the tactile probe, surface, and small hole are mathematically analyzed and evaluated. The deviations are a result of the tactile probe radius, the curvatures at the positions where small holes are drilled on the freeform surface, and the effect of the position error of the hole on focusing. An example case study is provided for the measurement of a pattern of small holes on an elliptical cylinder on the two machines. The absolute sum of the autofocusing deviations is 118 μm on the test rig and 144 μm on the machine tool. This is much less than the 500 μm depth of field of the optical microscope. Therefore, the method is capable of capturing a group of clear images of the small holes on this workpiece for either implementation.

21 CFR 173.320 - Chemicals for controlling microorganisms in cane-sugar and beet-sugar mills.

Code of Federal Regulations, 2010 CFR

2010-04-01

...-sugar and beet-sugar mills. 173.320 Section 173.320 Food and Drugs FOOD AND DRUG ADMINISTRATION... controlling microorganisms in cane-sugar and beet-sugar mills. Agents for controlling microorganisms in cane-sugar and beet-sugar mills may be safely used in accordance with the following conditions: (a) They are...

21 CFR 173.320 - Chemicals for controlling microorganisms in cane-sugar and beet-sugar mills.

Code of Federal Regulations, 2011 CFR

2011-04-01

...-sugar and beet-sugar mills. 173.320 Section 173.320 Food and Drugs FOOD AND DRUG ADMINISTRATION... controlling microorganisms in cane-sugar and beet-sugar mills. Agents for controlling microorganisms in cane-sugar and beet-sugar mills may be safely used in accordance with the following conditions: (a) They are...

21 CFR 173.320 - Chemicals for controlling microorganisms in cane-sugar and beet-sugar mills.

Code of Federal Regulations, 2013 CFR

2013-04-01

...-sugar and beet-sugar mills. 173.320 Section 173.320 Food and Drugs FOOD AND DRUG ADMINISTRATION... controlling microorganisms in cane-sugar and beet-sugar mills. Agents for controlling microorganisms in cane-sugar and beet-sugar mills may be safely used in accordance with the following conditions: (a) They are...

21 CFR 173.320 - Chemicals for controlling microorganisms in cane-sugar and beet-sugar mills.

Code of Federal Regulations, 2012 CFR

2012-04-01

...-sugar and beet-sugar mills. 173.320 Section 173.320 Food and Drugs FOOD AND DRUG ADMINISTRATION... controlling microorganisms in cane-sugar and beet-sugar mills. Agents for controlling microorganisms in cane-sugar and beet-sugar mills may be safely used in accordance with the following conditions: (a) They are...

Managing woodwaste: Yield from residue

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

Nielson, E.; Rayner, S.

1993-12-31

Historically, the majority of sawmill waste has been burned or buried for the sole purpose of disposal. In most jurisdictions, environmental legislation will prohibit, or render uneconomic, these practices. Many reports have been prepared to describe the forest industry`s residue and its environmental effect; although these help those looking for industry-wide or regional solutions, such as electricity generation, they have limited value for the mill manager, who has the on-hands responsibility for generation and disposal of the waste. If the mill manager can evaluate waste streams and break them down into their usable components, he can find niche market solutionsmore » for portions of the plant residue and redirect waste to poor/no-return, rather than disposal-cost, end uses. In the modern mill, residue is collected at the individual machine centre by waste conveyors that combine and mix sawdust, shavings, bark, etc. and send the result to the hog-fuel pile. The mill waste system should be analyzed to determine the measures that can improve the quality of residues and determine the volumes of any particular category before the mixing, mentioned above, occurs. After this analysis, the mill may find a niche market for a portion of its woodwaste.« less

Defining the Post-Machined Sub-surface in Austenitic Stainless Steels

NASA Astrophysics Data System (ADS)

Srinivasan, N.; Sunil Kumar, B.; Kain, V.; Birbilis, N.; Joshi, S. S.; Sivaprasad, P. V.; Chai, G.; Durgaprasad, A.; Bhattacharya, S.; Samajdar, I.

2018-04-01

Austenitic stainless steels grades, with differences in chemistry, stacking fault energy, and thermal conductivity, were subjected to vertical milling. Anodic potentiodynamic polarization was able to differentiate (with machining speed/strain rate) between different post-machined sub-surfaces in SS 316L and Alloy A (a Cu containing austenitic stainless steel: Sanicroe 28™), but not in SS 304L. However, such differences (in the post-machined sub-surfaces) were revealed in surface roughness, sub-surface residual stresses and misorientations, and in the relative presence of sub-surface Cr2O3 films. It was shown, quantitatively, that higher machining speed reduced surface roughness and also reduced the effective depths of the affected sub-surface layers. A qualitative explanation on the sub-surface microstructural developments was provided based on the temperature-dependent thermal conductivity values. The results herein represent a mechanistic understanding to rationalize the corrosion performance of widely adopted engineering alloys.

Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

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

Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

2010-10-04

Laboratory tests were conducted to determine the fatigue performance of AWJ-machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results not only confirmed the findings of the aluminum dog-bone specimens but also further enhance the fatigue performance. In addition, titanium is known to be notoriously difficult to cutmore » with contact tools while AWJs cut it 34% faster than stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred combination for processing aircraft titanium that is fatigue critical.« less

Defining the Post-Machined Sub-surface in Austenitic Stainless Steels

NASA Astrophysics Data System (ADS)

Srinivasan, N.; Sunil Kumar, B.; Kain, V.; Birbilis, N.; Joshi, S. S.; Sivaprasad, P. V.; Chai, G.; Durgaprasad, A.; Bhattacharya, S.; Samajdar, I.

2018-06-01

Austenitic stainless steels grades, with differences in chemistry, stacking fault energy, and thermal conductivity, were subjected to vertical milling. Anodic potentiodynamic polarization was able to differentiate (with machining speed/strain rate) between different post-machined sub-surfaces in SS 316L and Alloy A (a Cu containing austenitic stainless steel: Sanicroe 28™), but not in SS 304L. However, such differences (in the post-machined sub-surfaces) were revealed in surface roughness, sub-surface residual stresses and misorientations, and in the relative presence of sub-surface Cr2O3 films. It was shown, quantitatively, that higher machining speed reduced surface roughness and also reduced the effective depths of the affected sub-surface layers. A qualitative explanation on the sub-surface microstructural developments was provided based on the temperature-dependent thermal conductivity values. The results herein represent a mechanistic understanding to rationalize the corrosion performance of widely adopted engineering alloys.

The use of cutting temperature to evaluate the machinability of titanium alloys.

PubMed

Kikuchi, Masafumi

2009-02-01

This study investigated the machinability of titanium, two commercial titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb) and free-cutting brass using the cutting temperature. The cutting temperature was estimated by measuring the thermal electromotive force of the tool-workpiece thermocouple during cutting. The thermoelectric power of each metal relative to the tool had previously been determined. The metals were slotted using a milling machine and carbide square end mills under four cutting conditions. The cutting temperatures of Ti-6Al-4V and Ti-6Al-7Nb were significantly higher than that of the titanium, while that of the free-cutting brass was lower. This result coincided with the relationship of the magnitude of the cutting forces measured in a previous study. For each metal, the cutting temperature became higher when the depth of cut or the cutting speed and feed increased. The increase in the cutting speed and feed was more influential on the value than the increase in the depth of cut when two cutting conditions with the same removal rates were compared. The results demonstrated that cutting temperature measurement can be utilized to develop a new material for dental CAD/CAM applications and to optimize the cutting conditions.

SpaceBuoy: A University Nanosat Space Weather Mission

DTIC Science & Technology

2012-03-26

for all four-side panels. One design and one machine set-up allows a CNC mill to build them almost automatically. Lessons learned from components...in a dual probe configuration, for in situ plasma density) and interfacing with the spacecraft has been completed. Engineering development is

16. View of passage (formerly Spicket Street; later, railroad rightofway) ...

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

16. View of passage (formerly Spicket Street; later, railroad right-of-way) between Paper Machine Building (on left) and Wilder Mill (on right), from Canal Street; view to north. - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

Experimental research of kinetic and dynamic characteristics of temperature movements of machines

NASA Astrophysics Data System (ADS)

Parfenov, I. V.; Polyakov, A. N.

2018-03-01

Nowadays, the urgency of informational support of machines at different stages of their life cycle is increasing in the form of various experimental characteristics that determine the criteria for working capacity. The effectiveness of forming the base of experimental characteristics of machines is related directly to the duration of their field tests. In this research, the authors consider a new technique that allows reducing the duration of full-scale testing of machines by 30%. To this end, three new indicator coefficients were calculated in real time to determine the moments corresponding to the characteristic points. In the work, new terms for thermal characteristics of machine tools are introduced: kinetic and dynamic characteristics of the temperature movements of the machine. This allow taking into account not only the experimental values for the temperature displacements of the elements of the carrier system of the machine, but also their derivatives up to the third order, inclusively. The work is based on experimental data obtained in the course of full-scale thermal tests of a drilling-milling and boring CNC machine.

21 CFR 173.320 - Chemicals for controlling microorganisms in cane-sugar and beet-sugar mills.

Code of Federal Regulations, 2014 CFR

2014-04-01

...-sugar and beet-sugar mills. 173.320 Section 173.320 Food and Drugs FOOD AND DRUG ADMINISTRATION...-sugar and beet-sugar mills. Agents for controlling microorganisms in cane-sugar and beet-sugar mills may... microorganisms in cane-sugar and/or beet-sugar mills as specified in paragraph (b) of this section. (b) They are...

A static model of a Sendzimir mill for use in shape control

NASA Astrophysics Data System (ADS)

Gunawardene, G. W. D. M.

The design of shape control systems is an area of current interest in the steel industry. Shape is defined as the internal stress distribution resulting from a transverse variation in the reduction of the strip thickness. The object of shape control is to adjust the mill so that the rolled strip is free from internal stresses. Both static and dynamic models of the mill are required for the control system design.The subject of this thesis is the static model of the Sendzimir cold rolling mill, which is a 1-2-3-4 type cluster mill. The static model derived enables shape profiles to be calculated for a given set of actuator positions, and is used to generate the steady state mill gains. The method of calculation of these shape profiles is discussed. The shape profiles obtained for different mill schedules are plotted against the distance across the strip. The corresponding mill gains are calculated and these relate the shape changes to the actuator changes. These mill gains are presented in the form of a square matrix, obtained by measuring shape at eight points across the strip.

Modification of working conditions based on ergo THK reducing workload, muscle tension, and fatigue of rice milling workers in J village

NASA Astrophysics Data System (ADS)

Ruliati, L. P.; Adiputra, N.; Sutjana, I. D. P.; Sutajaya, I. M.

2017-11-01

Rice mill is one of the businesses in informal sector. From the rice milling process, ergonomic problems arise when employees work with bent position that done repeatedly to lift grain sacks to be transferred to peeler machine. This situation will affect the comfort of work, thus increasing the workload, muscle tension, and fatigue. The consequence will certainly affect the health and productivity of workers. In this study introduces ergo Tri Hita Karana (ergo THK) as an ergonomics intervention model which solves ergonomics problems of the cultural aspects of THK. The study aim is to determine the modification of working conditions based Ergo THK to reduce workload, muscle tension and fatigue. This research uses Randomized Pretest and Posttest Control Group Design experimental design. The subjects were 30 male rice mill workers with an age range of 16 until 56 years, and then divided into 15 subjects in the control group and 15 subjects in the treatment group. The results showed that the average posttest workloads in the control group are 136.950 more less 0.297 and in the treatment group are 107.60 more less 0.396. Significance analysis showed that after the two groups done their activities, the average workload significantly different p less than 0.005. The amount of reduction in the workload between the two groups was 21.43 percent. In muscle tension posttest showed that the mean score of the muscle tension in the control group was 62.67 more less 7.31 and the treatment group was 20.96 more less 2.96. Significance analysis showed that both groups mean muscle-tension results were significantly different p less than 0.005. The amount of reduction in tension between the control group and the treatment group while working was 66.55 percent. At fatigue posttest showed that the mean score of fatigue in the control group was 76.40 more less 13.51 and the treatment group was 55.53 more less 9.51. Significant analysis showed that the mean fatigue of both groups significantly different p less than 0.005. The amount of reduction in fatigue between the control group and the treatment group while working was 27.31 percent. From this study it can be concluded that the modification of the working conditions based on Ergo THK can reduce the workload by 21.43 percent, muscle tension by 66.55 percent and fatigue by 27.31 percent.

Safety concerns in composite manufacturing and machining

NASA Astrophysics Data System (ADS)

Asmatulu, Eylem; Alonayni, Abdullah; Alamir, Mohammed

2018-03-01

Because of the superior properties, composites have been used in many industrial applications, including aerospace, wind turbines, ships, cars, fishing rods, storage tanks, swimming pool panels, and baseball bats. Each application may require different combinations of reinforcements and matrices, which make the manufacturing safety even more challenging while working on these substances. In this study, safety issues in composite manufacturing and machining were investigated in detail, and latest developments were provided for workers. The materials most frequently used in composite manufacturing, such as matrix (polyester, vinylester, phenolic, epoxies, methyl ethyl ketone peroxide, benzoil peroxide, hardeners, and solvents), and reinforcement materials (carbon, glass and Kevlar fibers, honeycomb and foams) can be highly toxic to human body. These materials can also be very toxic to the environment when dumped out uncontrollably, creating major future health and environmental concerns. Throughout the manufacturing process, workers inhale vapors of the liquid matrix, hardeners and solvents / thinners, as well as reinforcement materials (chopped fibers and particles) in airborne. Milling, cutting and machining of the composites can further increase the toxic inhalations of airborne composite particles, resulting in major rashes, irritation, skin disorders, coughing, severe eye and lung injury and other serious illnesses. The major portions of these hazardous materials can be controlled using appropriate personal protective equipment for the chemicals and materials used in composite manufacturing and machining. This study provides best possible safety practices utilized in composite manufacturing facilities for workers, engineers and other participants.

Water requirements of the pulp and paper industry

USGS Publications Warehouse

Mussey, Orville D.

1955-01-01

Water, of varied qualities, is used for several purposes in the manufacture of pulp and paper, as a vehicle for transporting the constituents of paper in the paper machines; as process water for cooking wood chips to make pulp; as a medium for heat transfer; and for washing the pulpwood, the woodpulp, and the machines that handle the pulp. About 3,200 million gallons of water was withdrawn from surface- and ground-water sources each day during 1950 for the use of the pulp and paper industry. This is about 4 percent of the total estimated industrial withdrawal of water in the Nation The paper industry in the United States has been growing at a rapid rate. It has increased about tenfold in the last 50 years and has doubled every 15 years. The 1950 production of paper was about 24 million tons, which amounts to about 85 percent of the domestic consumption. In 1950, the pulp mills of the country produced more than 14 million tons of woodpulp, which supplied about 85 percent of the demand by the paper mills and other industries. The remainder of the fiber for paper manufacture was obtained from imported woodpulp, from reclaimed wastepaper, and from other fibers including rags and straw. The nationwide paper consumption for 1955 has been estimated at 31,700,000 tons. Woodpulp is classified according to the process by which it is made. Every woodpulp has characteristics that are carried over into the many and diverse grades of paper. Groundwood pulp is manufactured by simply grinding up wood and refining the resulting product. Soda, sulfite, and sulfate pulps are manufactured by chemically breaking down the lignin that cements the cellulose of the wood together and removing, cleaning, and sometimes bleaching the resulting fibers. Some woodpulp is produced by other methods. Sulfate-pulp mills are increasing in number and in rated daily capacity and are manufacturing more than half of the present domestic production of woodpulp. Most of the newer and larger woodpulp mills are manufacturing sulfate pulp; because of the antipollution laws, many sulfite-pulp mills are being converted to sulfate-pulp mills. The waste from the manufacture of a ton of sulfate pulp is much more readily disposed of than that from a ton of sulfite pulp. Pulp mills are located near the source of raw material, which means that they are located in the eastern half of the United States and in the Pacific Northwest. It is advantageous for paper mills to be located close to a market and therefore a large number of paper mills are in the northeastern section of the United States from Minnesota to Maine. However, much of the coarser paper, which will ship well, is produced close to the pulp mills. The entire process of making paper from pulpwood, with special reference to water use is briefly described to provide an understanding of how the water is used and reused.

Occupational hearing loss of market mill workers in the city of Accra, Ghana.

PubMed

Kitcher, Emmanuel D; Ocansey, Grace; Abaidoo, Benjamin; Atule, Alidu

2014-01-01

Noise induced hearing loss (NIHL) is an irreversible sensorineural hearing loss associated with exposure to high levels of excessive noise. Prevention measures are not well established in developing countries. This comparative cross sectional study aims to determine the prevalence of hearing loss in both a group of high risk workers and a control group and to assess their knowledge of the effects of noise on hearing health. A total of 101 market mill workers and 103 controls employed within markets in the city of Accra, Ghana, were evaluated using a structured questionnaire and pure tone audiometry. The questionnaire assessed factors including self-reported hearing loss, tinnitus, knowledge on the effects of noise on hearing health and the use of hearing protective devices. Pure tone audiometric testing was conducted for both mill workers and controls. Noise levels at the work premises of the mill workers and controls were measured. Symptoms of hearing loss were reported by 24 (23.76%) and 8 (7.7%) mill workers and controls respectively. Fifty-five (54.5%) and fifty-four (52.37%) mill workers and controls exhibited knowledge of the effects of noise on hearing health. Five (5.0%) mill workers used hearing protective devices. There was significant sensorineural hearing loss and the presence of a 4 kHz audiometric notch among mill workers when compared with controls for the mean thresholds of 2 kHz, 3 kHz and 4 kHz (P = 0. 001). The prevalence of hearing loss in the better hearing ears of the mill workers and controls was 24.8% and 4.8% respectively (P < 0.5). The prevalence of hearing loss, which may be characteristic of NIHL in the better hearing ears of the mill workers and controls was 24.8% and 4.8% respectively. The majority of mill workers did not use hearing protection.

17. View of passage (formerly Spicket Street; later, railroad rightofway) ...

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

17. View of passage (formerly Spicket Street; later, railroad right-of-way) between Paper Machine Building (on left) and Wilder Mill (on right), from inside security fence; view to north. - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

49. VIEW FROM WEST OF DUST COLLECTOR BLOWER LOCATED AT ...

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

49. VIEW FROM WEST OF DUST COLLECTOR BLOWER LOCATED AT CRUSHED OXIDIZED ORE BIN FEED LEVEL. THE ROASTER IS BEYOND AND THE MACHINE SHOP IS ON THE TRAM TERRACE, UPPER RIGHT. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Proposal of Modification Strategy of NC Program in the Virtual Manufacturing Environment

NASA Astrophysics Data System (ADS)

Narita, Hirohisa; Chen, Lian-Yi; Fujimoto, Hideo; Shirase, Keiichi; Arai, Eiji

Virtual manufacturing will be a key technology in process planning, because there are no evaluation tools for cutting conditions. Therefore, virtual machining simulator (VMSim), which can predict end milling processes, has been developed. The modification strategy of NC program using VMSim is proposed in this paper.

Sikorsky interactive graphics surface design/manufacturing system

NASA Technical Reports Server (NTRS)

Robbins, R.

1975-01-01

An interactive graphics system conceived to be used in the design, analysis, and manufacturing of aircraft components with free form surfaces was described. In addition to the basic surface definition and viewing capabilities inherent in such a system, numerous other features are present: surface editing, automated smoothing of control curves, variable milling patch boundary definitions, surface intersection definition and viewing, automatic creation of true offset surfaces, digitizer and drafting machine interfaces, and cutter path optimization. Documented costs and time savings of better than six to one are being realized with this system. The system was written in FORTRAN and GSP for use on IBM 2250 CRT's in conjunction with an IBM 370/158 computer.

The effect of multicolored machinable ceramics on the esthetics of all-ceramic crowns.

PubMed

Reich, Sven; Hornberger, Helga

2002-07-01

Computer-aided design/computer-assisted machining systems offer the possibility of fabricating restorations from one machinable ceramic block. Whether multishaded blocks improve esthetic results and are a viable alternative to individually stained ceramics has not been fully determined. The aim of this investigation was to examine the effect of multishaded blocks on the esthetic appearance of all-ceramic CEREC crowns and compare these crowns with single-shade and stained restorations. Ten subjects were included in this study. For each subject, 6 different crowns were milled with the use of a CEREC machine. One crown was milled from each of the following machinable ceramic materials: CEREC Vitablocs Mark II in classic colors; Vitablocs Mark II in 3D-Master colors; Vitablocs Mark II in either classic or 3D-Master colors, with additional staining; Megadenta Bloxx multishaded; Mark II experimental multilayer; and an experimental multilayer leucite ceramic. Three independent examiners assessed the esthetic appearance of crowns fabricated to match each subject's anterior tooth shade. A scale of 1 to 6 was used to score the shade match and esthetic adaptation of each crown, with 1 representing excellent characteristics and 3.5 serving as the threshold for clinical acceptability. The examiners' scores were averaged, and the mean values were analyzed with the Wilcoxon signed rank test (P

Hybrid micromachining using a nanosecond pulsed laser and micro EDM

NASA Astrophysics Data System (ADS)

Kim, Sanha; Kim, Bo Hyun; Chung, Do Kwan; Shin, Hong Shik; Chu, Chong Nam

2010-01-01

Micro electrical discharge machining (micro EDM) is a well-known precise machining process that achieves micro structures of excellent quality for any conductive material. However, the slow machining speed and high tool wear are main drawbacks of this process. Though the use of deionized water instead of kerosene as a dielectric fluid can reduce the tool wear and increase the machine speed, the material removal rate (MRR) is still low. In contrast, laser ablation using a nanosecond pulsed laser is a fast and non-wear machining process but achieves micro figures of rather low quality. Therefore, the integration of these two processes can overcome the respective disadvantages. This paper reports a hybrid process of a nanosecond pulsed laser and micro EDM for micromachining. A novel hybrid micromachining system that combines the two discrete machining processes is introduced. Then, the feasibility and characteristics of the hybrid machining process are investigated compared to conventional EDM and laser ablation. It is verified experimentally that the machining time can be effectively reduced in both EDM drilling and milling by rapid laser pre-machining prior to micro EDM. Finally, some examples of complicated 3D micro structures fabricated by the hybrid process are shown.

An experimental analysis of process parameters to manufacture micro-channels in AISI H13 tempered steel by laser micro-milling

NASA Astrophysics Data System (ADS)

Teixidor, D.; Ferrer, I.; Ciurana, J.

2012-04-01

This paper reports the characterization of laser machining (milling) process to manufacture micro-channels in order to understand the incidence of process parameters on the final features. Selection of process operational parameters is highly critical for successful laser micromachining. A set of designed experiments is carried out in a pulsed Nd:YAG laser system using AISI H13 hardened tool steel as work material. Several micro-channels have been manufactured as micro-mold cavities varying parameters such as scanning speed (SS), pulse intensity (PI) and pulse frequency (PF). Results are obtained by evaluating the dimensions and the surface finish of the micro-channel. The dimensions and shape of the micro-channels produced with laser-micro-milling process exhibit variations. In general the use of low scanning speeds increases the quality of the feature in both surface finishing and dimensional.

Digitally Milled Metal Framework for Fixed Complete Denture with Metal Occlusal Surfaces: A Design Concept.

PubMed

AlBader, Bader; AlHelal, Abdulaziz; Proussaefs, Periklis; Garbacea, Antonela; Kattadiyil, Mathew T; Lozada, Jaime

Implant-supported fixed complete dentures, often referred to as hybrid prostheses, have been associated with high implant survival rates but also with a high incidence of mechanical prosthetic complications. The most frequent of these complications have been fracture and wear of the veneering material. The proposed design concept incorporates the occlusal surfaces of the posterior teeth as part of a digital milled metal framework by designing the posterior first molars in full contour as part of the framework. The framework can be designed, scanned, and milled from a titanium blank using a milling machine. Acrylic resin teeth can then be placed on the framework by conventional protocol. The metal occlusal surfaces of the titanium-countered molars will be at centric occlusion. It is hypothesized that metal occlusal surfaces in the posterior region may reduce occlusal wear in these types of prostheses. When the proposed design protocol is followed, the connection between the metal frame and the cantilever part of the prosthesis is reinforced, which may lead to fewer fractures of the metal framework.

Brittleness index of machinable dental materials and its relation to the marginal chipping factor.

PubMed

Tsitrou, Effrosyni A; Northeast, Simon E; van Noort, Richard

2007-12-01

The machinability of a material can be measured with the calculation of its brittleness index (BI). It is possible that different materials with different BI could produce restorations with varied marginal integrity. The degree of marginal chipping of a milled restoration can be estimated by the calculation of the marginal chipping factor (CF). The aim of this study is to investigate any possible correlation between the BI of machinable dental materials and the CF of the final restorations. The CEREC system was used to mill a wide range of materials used with that system; namely the Paradigm MZ100 (3M/ESPE), Vita Mark II (VITA), ProCAD (Ivoclar-Vivadent) and IPS e.max CAD (Ivoclar-Vivadent). A Vickers Hardness Tester was used for the calculation of BI, while for the calculation of CF the percentage of marginal chipping of crowns prepared with bevelled marginal angulations was estimated. The results of this study showed that Paradigm MZ100 had the lowest BI and CF, while IPS e.max CAD demonstrated the highest BI and CF. Vita Mark II and ProCAD had similar BI and CF and were lying between the above materials. Statistical analysis of the results showed that there is a perfect positive correlation between BI and CF for all the materials. The BI and CF could be both regarded as indicators of a material's machinability. Within the limitations of this study it was shown that as the BI increases so does the potential for marginal chipping, indicating that the BI of a material can be used as a predictor of the CF.

Comparison of five-axis milling and rapid prototyping for implant surgical templates.

PubMed

Park, Ji-Man; Yi, Tae-Kyoung; Koak, Jai-Young; Kim, Seong-Kyoon; Park, Eun-Jin; Heo, Seong-Joo

2014-01-01

This study aims to compare and evaluate the accuracy of surgical templates fabricated using coordinate synchronization processing with five-axis milling and design-related processing with rapid prototyping (RP). Master phantoms with 10 embedded gutta-percha cylinders hidden under artificial gingiva were fabricated and imaged using cone beam computed tomography. Vectors of the hidden cylinders were extracted and transferred to those of the planned implants through reverse engineering using virtual planning software. An RP-produced template was fabricated by stereolithography in photopolymer at the RP center according to planned data. Metal sleeves were bonded after holes were bored (group RP). For the milled template, milling coordinates were synchronized using the conversion process for the coordinate synchronization platform located on the model's bottom. Metal bushings were set on holes milled on the five-axis milling machine, on which the model was fixed through the coordinate synchronization plate, and the framework was constructed on the model using orthodontic resin (group CS). A computed tomography image was taken with templates firmly fixed on models using anchor pins (RP) or anchor screws (CS). The accuracy was analyzed via reverse engineering. Differences between the two groups were compared by repeated measures two-factor analysis. From the reverse-engineered image of the template on the experimental model, RP-produced templates showed significantly larger deviations than did milled surgical guides. Maximum deviations of the group RP were 1.58 mm (horizontal), 1.68 mm (vertical), and 8.51 degrees (angular); those of the group CS were 0.68 mm (horizontal), 0.41 mm (vertical), and 3.23 degrees (angular). A comparison of milling and RP template production methods showed that a vector-milled surgical guide had significantly smaller deviations than did an RP-produced template. The accuracy of computer-guided milled surgical templates was within the safety margin of previous studies.

Orion Heat Shield

NASA Image and Video Library

2015-05-06

OVERSEEING ORION HEAT SHIELD WORK IN MARSHALL'S SEVEN-AXIS MILLING AND MACHINING FACILITY ARE, FROM LEFT, JOHN KOWAL, MANAGER OF ORION'S THERMAL PROTECTION SYSTEM AT JOHNSON SPACE CENTER; NICHOLAS CROWLEY, AN AMES ENGINEERING TECHNICIAN; AND ROB KORNIENKO, AMES ENGINEERING BRANCH CHIEF. THE HEAT SHIELD FLEW TO SPACE DURING THE EFT-1 FULL SCALE FLIGHT TEST OF ORION IN DECEMBER, 2014

15. View of passage (formerly Spicket Street; later, railroad rightofway) ...

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

15. View of passage (formerly Spicket Street; later, railroad right-of-way) between Wilder Mill (on left) and Paper Machine Building (on right), showing collapsed area of stone arch bridge spanning raceway in foreground; view to south - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

Monitoring Method of Cutting Force by Using Additional Spindle Sensors

NASA Astrophysics Data System (ADS)

Sarhan, Ahmed Aly Diaa; Matsubara, Atsushi; Sugihara, Motoyuki; Saraie, Hidenori; Ibaraki, Soichi; Kakino, Yoshiaki

This paper describes a monitoring method of cutting forces for end milling process by using displacement sensors. Four eddy-current displacement sensors are installed on the spindle housing of a machining center so that they can detect the radial motion of the rotating spindle. Thermocouples are also attached to the spindle structure in order to examine the thermal effect in the displacement sensing. The change in the spindle stiffness due to the spindle temperature and the speed is investigated as well. Finally, the estimation performance of cutting forces using the spindle displacement sensors is experimentally investigated by machining tests on carbon steel in end milling operations under different cutting conditions. It is found that the monitoring errors are attributable to the thermal displacement of the spindle, the time lag of the sensing system, and the modeling error of the spindle stiffness. It is also shown that the root mean square errors between estimated and measured amplitudes of cutting forces are reduced to be less than 20N with proper selection of the linear stiffness.

Experimental study of surface integrity and fatigue life in the face milling of inconel 718

NASA Astrophysics Data System (ADS)

Wang, Xiangyu; Huang, Chuanzhen; Zou, Bin; Liu, Guoliang; Zhu, Hongtao; Wang, Jun

2018-06-01

The Inconel 718 alloy is widely used in the aerospace and power industries. The machining-induced surface integrity and fatigue life of this material are important factors for consideration due to high reliability and safety requirements. In this work, the milling of Inconel 718 was conducted at different cutting speeds and feed rates. Surface integrity and fatigue life were measured directly. The effects of cutting speed and feed rate on surface integrity and their further influences on fatigue life were analyzed. Within the chosen parameter range, the cutting speed barely affected the surface roughness, whereas the feed rate increased the surface roughness through the ideal residual height. The surface hardness increased as the cutting speed and feed rate increased. Tensile residual stress was observed on the machined surface, which showed improvement with the increasing feed rate. The cutting speed was not an influencing factor on fatigue life, but the feed rate affected fatigue life through the surface roughness. The high surface roughness resulting from the high feed rate could result in a high stress concentration factor and lead to a low fatigue life.

Reducing tool wear by partial cladding of critical zones in hot form tool by laser metal deposition

NASA Astrophysics Data System (ADS)

Vollmer, Robert; Sommitsch, Christof

2017-10-01

This paper points out a production method to reduce tool wear in hot stamping applications. Usually tool wear can be observed at locally strongly stressed areas superimposed with gliding movement between blank and tool surface. The shown solution is based on a partial laser cladding of the tool surface with a wear resistant coating to increase the lifespan of tool inserts. Preliminary studies showed good results applying a material combination of tungsten carbide particles embedded in a metallic matrix. Different Nickel based alloys welded on hot work tool steel (1.2343) were tested mechanically in the interface zone. The material with the best bonding characteristic is chosen and reinforced with spherical tungsten carbide particles in a second laser welding step. Since the machining of tungsten carbides is very elaborate a special manufacturing strategy is developed to reduce the milling effort as much as possible. On special test specimens milling tests are carried out to proof the machinability. As outlook a tool insert of a b-pillar is coated to perform real hot forming tests.

Cutting Zone Temperature Identification During Machining of Nickel Alloy Inconel 718

NASA Astrophysics Data System (ADS)

Czán, Andrej; Daniš, Igor; Holubják, Jozef; Zaušková, Lucia; Czánová, Tatiana; Mikloš, Matej; Martikáň, Pavol

2017-12-01

Quality of machined surface is affected by quality of cutting process. There are many parameters, which influence on the quality of the cutting process. The cutting temperature is one of most important parameters that influence the tool life and the quality of machined surfaces. Its identification and determination is key objective in specialized machining processes such as dry machining of hard-to-machine materials. It is well known that maximum temperature is obtained in the tool rake face at the vicinity of the cutting edge. A moderate level of cutting edge temperature and a low thermal shock reduce the tool wear phenomena, and a low temperature gradient in the machined sublayer reduces the risk of high tensile residual stresses. The thermocouple method was used to measure the temperature directly in the cutting zone. An original thermocouple was specially developed for measuring of temperature in the cutting zone, surface and subsurface layers of machined surface. This paper deals with identification of temperature and temperature gradient during dry peripheral milling of Inconel 718. The measurements were used to identification the temperature gradients and to reconstruct the thermal distribution in cutting zone with various cutting conditions.

Computer Aided Simulation Machining Programming In 5-Axis Nc Milling Of Impeller Leaf

NASA Astrophysics Data System (ADS)

Huran, Liu

At present, cad/cam (computer-aided design and manufacture) have fine wider and wider application in mechanical industry. For the complex surfaces, the traditional machine tool can no longer satisfy the requirement of such complex task. Only by the help of cad/cam can fulfill the requirement. The machining of the vane surface of the impeller leaf has been considered as the hardest challenge. Because of their complex shape, the 5-axis cnc machine tool is needed for the machining of such parts. The material is hard to cut, the requirement for the surface finish and clearance is very high, so that the manufacture quality of impeller leaf represent the level of 5-axis machining. This paper opened a new field in machining the complicated surface, based on a relatively more rigid mathematical basis. The theory presented here is relatively more systematical. Since the lack of theoretical guidance, in the former research, people have to try in machining many times. Such case will be changed. The movement of the cutter determined by this method is definite, and the residual is the smallest while the times of travel is the fewest. The criterion is simple and the calculation is easy.

The optimization study on the tool wear of carbide cutting tool during milling Carbon Fibre Reinforced (CFRP) using Response Surface Methodology (RSM)

NASA Astrophysics Data System (ADS)

Nor Khairusshima, M. K.; Hafiz Zakwan, B. Muhammad; Suhaily, M.; Sharifah, I. S. S.; Shaffiar, N. M.; Rashid, M. A. N.

2018-01-01

Carbon Fibre Reinforced Plastic (CFRP) composite has become one of famous materials in industry, such as automotive, aeronautics, aerospace and aircraft. CFRP is attractive due to its properties, which promising better strength and high specification of mechanical properties other than its high resistance to corrosion. Other than being abrasive material due to the carbon nature, CFRP is an anisotropic material, which the knowledge of machining metal and steel cannot be applied during machining CFRP. The improper technique and parameters used to machine CFRP may result in high tool wear. This paper is to study the tool wear of 8 mm diameter carbide cutting tool during milling CFRP. To predict the suitable cutting parameters within range of 3500-6220 (rev/min), 200-245 (mm/min), and 0.4-1.8 (mm) for cutting speed, speed, feed rate and depth of cut respectively, which produce optimized result (less tool wear), Response Surface Methodology (RSM) has been used. Based on the developed mathematical model, feed rate was identified as the primary significant item that influenced tool wear. The optimized cutting parameters are cutting speed, feed and depth of cut of 3500 rev/min, 200 mm/min and 0.5 mm, respectively, with tool wear of 0.0267 mm. It is also can be observed that as the cutting speed and feed rate increased the tool wear is increasing.

Eco-friendly rubberized cotton fabric roller for ginning machines.

PubMed

Iyer, G V

2007-01-01

This article discusses the pollution caused by chrome composite leather-clad (CCLC) rollers commonly used in cotton roller ginning mills and suggests an alternative roller material. CCLC rollers contain about 18,000 to 36,000 mg/kg (ppm) total chromium in trivalent and hexavalent forms, which are toxic to human health and carcinogenic. When seed-cotton is processed in double roller (DR) ginning machines, the lint is contaminated with chromium, and chromium particles are carried into the spun yarns and cotton by-products. Specifically, due to persistent rubbing of the leather-clad roller over the stationary knife during the ginning process, the lint is contaminated with about 140 to 1990 ppm of chromium, and the spun yarns and cotton by-products contain about 100 to 200 ppm, far in excess of the standard limit of 0.1 ppm. Gin and mill workers are directly exposed to this carcinogenic substance. To offset this problem, pollution-free rubberized cotton fabric (RCF) rollers have been fabricated and tested in roller gins. The RCF roller covering is made of multiple layers of fabric bonded together using a white rubber compound, which has a surface finish conducive to high ginning efficiency. This eliminates chromium contamination and pollution during the ginning process. On the basis of the design and development of various test rollers and subsequent evaluation studies, the performance of pollution-free RCF rollers has been demonstrated with reference to their commercial benefit and eco-friendliness in cotton ginning mills.

A review on application of nanofluid MQL in machining

NASA Astrophysics Data System (ADS)

Rifat, Mustafa; Rahman, Md. Habibor; Das, Debashish

2017-12-01

Heat generation is an inevitable phenomenon during machining. To eradicate heat oriented detrimental effects like surface burning, tool wear and so on-different types of cooling system are being used. Traditional flood cooling method is the most widely used technique; however the consumption rate of coolant is very high. Moreover, if it is not deposited or recycled properly, it may also cause environmental hazard. Minimum Quantity Lubrication (MQL), on the other hand, sprays lubricant which decreases the frictional force and heat produced during machining. Nanofluid MQL is the incorporation of especially engineered nanoparticles into the lubricant that increases the heat carrying capacity. In this paper, four manufacturing processes (grinding, turning, milling, and drilling) and the effect of using nanofluid MQL in them are studied and summarized. Parameters that are considered in this study are cutting force, surface roughness, machining temperature, tool wear and environmental aspects. It can be observed that using nanofluids in an optimized manner can be beneficial to the machining processes because of their superior characteristics.

Machining of Aircraft Titanium with Abrasive-Waterjets for Fatigue Critical Applications

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

Liu, H. T.; Hovanski, Yuri; Dahl, Michael E.

2012-02-01

Laboratory tests were conducted to determine the fatigue performance of abrasive-waterjet- (AWJ-) machined aircraft titanium. Dog-bone specimens machined with AWJs were prepared and tested with and without sanding and dry-grit blasting with Al2O3 as secondary processes. The secondary processes were applied to remove the visual appearance of AWJ-generated striations and to clean up the garnet embedment. The fatigue performance of AWJ-machined specimens was compared with baseline specimens machined with CNC milling. Fatigue test results of the titanium specimens not only confirmed our previous findings in aluminum dog-bone specimens but in comparison also further enhanced the fatigue performance of the titanium.more » In addition, titanium is known to be difficult to cut, particularly for thick parts, however AWJs cut the material 34% faster han stainless steel. AWJ cutting and dry-grit blasting are shown to be a preferred ombination for processing aircraft titanium that is fatigue critical.« less

4. Credit JPL. Original 4" x 5" black and white ...

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

4. Credit JPL. Original 4" x 5" black and white negative housed in the JPL Archives, Pasadena, California. This interior view displays the machine shop in the Administration/Shops Building (the compass angle of the view is undetermined). Looking clockwise from the lower left, the machine tools in view are a power hacksaw, a heat-treatment oven (with white gloves on top), a large hydraulic press with a tool grinder at its immediate right; along the wall in the back of the view are various unidentified machine tool attachments and a vertical milling machine. In the background, a machinist is operating a radial drilling machine, to the right of which is a small drill press. To the lower right, another machinist is operating a Pratt & Whitney engine lathe; behind the operator stand a workbench and vertical bandsaw (JPL negative no. 384-10939, 29 July 1975). - Jet Propulsion Laboratory Edwards Facility, Administration & Shops Building, Edwards Air Force Base, Boron, Kern County, CA

Study of the influence of the cutting temperature on the magnitude of the contact forces in the machining fixtures

NASA Astrophysics Data System (ADS)

Cioată, V. G.; Kiss, I.; Alexa, V.; Raţiu, S. A.; Racov, M.

2018-01-01

In the machining process, the workpieces are installed in machining fixtures in order to establish a strictly determined position with the cutting tool or its trajectory. During the cutting process, the weight of the workpiece, the forces and moments of inertia, cutting forces and moments, clamping forces, the heat released during the cutting process determine the contact forces between the locators and the workpiece. The magnitude of these forces is important because too large value can destroy the surface of the workpiece, and a too small value can cause the workpiece to slip on the locators or even the loss of the contact with the workpiece. Both situations must be avoided. The paper presents a study, realized with CAE software, regarding the influence of the cutting temperature on the magnitude of the contact forces in a machining fixture for the milling a rectangular workpiece.

Comparison of peri-implant bone formation around injection-molded and machined surface zirconia implants in rabbit tibiae

PubMed Central

Kim, Hong-Kyun; Woo, Kyung mi; Shon, Won-Jun; Ahn, Jin-Soo; Cha, Seunghee; Park, Young-Seok

2017-01-01

The aim of this study was to compare osseointegration and surface characteristics of zirconia implants made by the powder injection molding (PIM) technique and made by the conventional milling procedure in rabbit tibiae. Surface characteristics of 2 types of implant were evaluated. Sixteeen rabbits received 2 types of external hex implants with similar geometry, machined zirconia implants and PIM zirconia implants, in the tibiae. Removal torque tests and histomorphometric analyses were performed. The roughness of PIM zirconia implants was higher than that of machined zirconia implants. The PIM zirconia implants exhibited significantly higher bone-implant contact and removal torque values than the machined zirconia implants (P < 0.001). The osseointegration of the PIM zirconia implant is promising, and PIM, using the roughened mold etching technique, can produce substantially rough surfaces on zirconia implants. PMID:26235717

Spring Internship 2018 at the Prototype Development Lab: A place of Dreamers and Makers

NASA Technical Reports Server (NTRS)

Rueda, Juan F.

2018-01-01

This paper covers the role of the design process and the methodology of creating a trophy during my Spring 2018 Internship at the Prototype Development Laboratory at the Kennedy Space Center. In the course of this project I used many new machines and materials while trying to deliver a professional product for a competition that invites college student teams from across the country. The machines covered in this paper include the wood chop saw, CNC mill, water jet, laser engraver, and the 3D printer. This paper also serves as an assembly guide for the trophy.

Process of making cryogenically cooled high thermal performance crystal optics

DOEpatents

Kuzay, Tuncer M.

1992-01-01

A method for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N.sub.2 is pumped through the porous material at a sub-cooled cryogenic inlet temperature and with sufficient system pressure to prevent the fluid bulk temperature from reaching saturation.

Process of making cryogenically cooled high thermal performance crystal optics

DOEpatents

Kuzay, T.M.

1992-06-23

A method is disclosed for constructing a cooled optic wherein one or more cavities are milled, drilled or formed using casting or ultrasound laser machining techniques in a single crystal base and filled with porous material having high thermal conductivity at cryogenic temperatures. A non-machined strain-free single crystal can be bonded to the base to produce superior optics. During operation of the cooled optic, N[sub 2] is pumped through the porous material at a sub-cooled cryogenic inlet temperature and with sufficient system pressure to prevent the fluid bulk temperature from reaching saturation. 7 figs.

Scanning Electron Microscopy Analysis of the Adaptation of Single-Unit Screw-Retained Computer-Aided Design/Computer-Aided Manufacture Abutments After Mechanical Cycling.

PubMed

Markarian, Roberto Adrian; Galles, Deborah Pedroso; Gomes França, Fabiana Mantovani

To measure the microgap between dental implants and custom abutments fabricated using different computer-aided design/computer-aided manufacture (CAD/CAM) methods before and after mechanical cycling. CAD software (Dental System, 3Shape) was used to design a custom abutment for a single-unit, screw-retained crown compatible with a 4.1-mm external hexagon dental implant. The resulting stereolithography file was sent for manufacturing using four CAD/CAM methods (n = 40): milling and sintering of zirconium dioxide (ZO group), cobalt-chromium (Co-Cr) sintered via selective laser melting (SLM group), fully sintered machined Co-Cr alloy (MM group), and machined and sintered agglutinated Co-Cr alloy powder (AM group). Prefabricated titanium abutments (TI group) were used as controls. Each abutment was placed on a dental implant measuring 4.1× 11 mm (SA411, SIN) inserted into an aluminum block. Measurements were taken using scanning electron microscopy (SEM) (×4,000) on four regions of the implant-abutment interface (IAI) and at a relative distance of 90 degrees from each other. The specimens were mechanically aged (1 million cycles, 2 Hz, 100 N, 37°C) and the IAI width was measured again using the same approach. Data were analyzed using two-way analysis of variance, followed by the Tukey test. After mechanical cycling, the best adaptation results were obtained from the TI (2.29 ± 1.13 μm), AM (3.58 ± 1.80 μm), and MM (1.89 ± 0.98 μm) groups. A significantly worse adaptation outcome was observed for the SLM (18.40 ± 20.78 μm) and ZO (10.42 ± 0.80 μm) groups. Mechanical cycling had a marked effect only on the AM specimens, which significantly increased the microgap at the IAI. Custom abutments fabricated using fully sintered machined Co-Cr alloy and machined and sintered agglutinated Co-Cr alloy powder demonstrated the best adaptation results at the IAI, similar to those obtained with commercial prefabricated titanium abutments after mechanical cycling. The adaptation of custom abutments made by means of SLM or milling and sintering of zirconium dioxide were worse both before and after mechanical cycling.

Evaluation of internal fit of interim crown fabricated with CAD/CAM milling and 3D printing system.

PubMed

Lee, Wan-Sun; Lee, Du-Hyeong; Lee, Kyu-Bok

2017-08-01

This study is to evaluate the internal fit of the crown manufactured by CAD/CAM milling method and 3D printing method. The master model was fabricated with stainless steel by using CNC machine and the work model was created from the vinyl-polysiloxane impression. After scanning the working model, the design software is used to design the crown. The saved STL file is used on the CAD/CAM milling method and two types of 3D printing method to produce 10 interim crowns per group. Internal discrepancy measurement uses the silicon replica method and the measured data are analyzed with One-way ANOVA to verify the statistic significance. The discrepancy means (standard deviation) of the 3 groups are 171.6 (97.4) µm for the crown manufactured by the milling system and 149.1 (65.9) and 91.1 (36.4) µm, respectively, for the crowns manufactured with the two types of 3D printing system. There was a statistically significant difference and the 3D printing system group showed more outstanding value than the milling system group. The marginal and internal fit of the interim restoration has more outstanding 3D printing method than the CAD/CAM milling method. Therefore, the 3D printing method is considered as applicable for not only the interim restoration production, but also in the dental prosthesis production with a higher level of completion.

A semi-automated process for the production of custom-made shoes

NASA Technical Reports Server (NTRS)

Farmer, Franklin H.

1991-01-01

A more efficient, cost-effective and timely way of designing and manufacturing custom footware is needed. A potential solution to this problem lies in the use of computer-aided design and manufacturing (CAD/CAM) techniques in the production of custom shoes. A prototype computer-based system was developed, and the system is primarily a software entity which directs and controls a 3-D scanner, a lathe or milling machine, and a pattern-cutting machine to produce the shoe last and the components to be assembled into a shoe. The steps in this process are: (1) scan the surface of the foot to obtain a 3-D image; (2) thin the foot surface data and create a tiled wire model of the foot; (3) interactively modify the wire model of the foot to produce a model of the shoe last; (4) machine the last; (5) scan the surface of the last and verify that it correctly represents the last model; (6) design cutting patterns for shoe uppers; (7) cut uppers; (8) machine an inverse mold for the shoe innersole/sole combination; (9) mold the innersole/sole; and (10) assemble the shoe. For all its capabilities, this system still requires the direction and assistance of skilled operators, and shoemakers to assemble the shoes. Currently, the system is running on a SUN3/260 workstation with TAAC application accelerator. The software elements of the system are written in either Fortran or C and run under a UNIX operator system.

Smart manufacturing of complex shaped pipe components

NASA Astrophysics Data System (ADS)

Salchak, Y. A.; Kotelnikov, A. A.; Sednev, D. A.; Borikov, V. N.

2018-03-01

Manufacturing industry is constantly improving. Nowadays the most relevant trend is widespread automation and optimization of the production process. This paper represents a novel approach for smart manufacturing of steel pipe valves. The system includes two main parts: mechanical treatment and quality assurance units. Mechanical treatment is performed by application of the milling machine with implementation of computerized numerical control, whilst the quality assurance unit contains three testing modules for different tasks, such as X-ray testing, optical scanning and ultrasound testing modules. The advances of each of them provide reliable results that contain information about any failures of the technological process, any deviations of geometrical parameters of the valves. The system also allows detecting defects on the surface or in the inner structure of the component.

Comparison of fiber orientation and tensile-stiffness orientation measurements in paper

Treesearch

David W. Vahey; John M. Considine; Andy Kahra; Mark Scotch

2008-01-01

We have had the opportunity to subject cross-machine paper strips from two mills to both ultrasound and optical "fiber-orientation" tests to examine the relationships between the results. Both determine an orientation angle, in degrees. Both measure sheet anisotropy as an MD/CD orientation ratio. The optical test has no counterpart to the ultrasonic...

Software analyzes feasibility of saw kerf reduction for hardwood mills

Treesearch

Philip H. Steele

2005-01-01

Reductions in saw kerf on head rigs and resaws can dramatically increase lumber recovery in hardwood sawmills. Research has shown that lumber sawing variation reduction will increase lumber recovery above that obtained solely from kerf reduction. Reductions in sawing machine kerf or variation always come at some cost in both capital and variable costs. Determining...

Gas flow parameters in laser cutting of wood- nozzle design

Treesearch

Kali Mukherjee; Tom Grendzwell; Parwaiz A.A. Khan; Charles McMillin

1990-01-01

The Automated Lumber Processing System (ALPS) is an ongoing team research effort to optimize the yield of parts in a furniture rough mill. The process is designed to couple aspects of computer vision, computer optimization of yield, and laser cutting. This research is focused on optimizing laser wood cutting. Laser machining of lumber has the advantage over...

The ultrasonic machining of silicon carbide / alumina composites

NASA Astrophysics Data System (ADS)

Nicholson, Garth Martyn John

Silicon carbide fibre reinforced alumina is a ceramic composite which was developed in conjunction with the Rolls-Royce Aerospace Group. The material is intended for use in the latest generation of jet engines, specifically for high temperature applications such as flame holders, combustor barrel segments and turbine blade tip seals. The material in question has properties which have been engineered by optimizing fibre volume fractions, weaves and fibre interface materials to meet the following main requirements : high thermal resistance, high thermal shock resistance and low density.Components intended for manufacture using this material will use the "direct metal oxidation" (DIMOX) method. This process involves manufacturing a near net shape component from the woven fibre matting, and infiltrating the matting with the alumina matrix material. Some of the components outlined require high tolerance features to be included in their design. The combustor barrel segments for example require slots to be formed within them for sealing purposes, the dimensions of these features preclude their formation using DIMOX, and therefore require a secondary process to be performed. Conventional machining techniques such as drilling, turning and milling cannot be used because of the brittle nature of the material. Electrodischarge machining (E.D.M.) cannot be used since the material is an insulator. Electrochemical machining (E.C.M.) cannot be used since the material is chemically inert. One machining method which could be used is ultrasonic machining (U.S.M.).The research programme investigated the feasibility of using ultrasonic machining as a manufacturing method for this new fibre reinforced composite. Two variations of ultrasonic machining were used : ultrasonic drilling and ultrasonic milling. Factors such as dimensional accuracy, surface roughness and delamination effects were examined. Previously performed ultrasonic machining experimental programmes were reviewed, as well as process models which have been developed. The process models were found to contain empirical constants which usually require specific material data for their calculation.Since a limited amount of the composite was available, and ultrasonic machining has many process variables, a Taguchi factorial experiment was conducted in order to ascertain the most relevant factors in machining. A full factorial experiment was then performed using the relevant factors. Techniques used in the research included both optical and scanning electron microscopy, surface roughness analysis, x-ray analysis and finite element stress analysis. A full set of machining data was obtained including relationships between the factors examined and both material removal rates, and surface roughness values. An attempt was made to explain these findings by examining established brittle fracture mechanisms. These established mechanisms did not seem to apply entirely to this material, an alternative method of material removal is therefore proposed. It is hoped that the data obtained from this research programme may contribute to the development of a more realistic mathematical model.

Optimization of processing parameters of UAV integral structural components based on yield response

NASA Astrophysics Data System (ADS)

Chen, Yunsheng

2018-05-01

In order to improve the overall strength of unmanned aerial vehicle (UAV), it is necessary to optimize the processing parameters of UAV structural components, which is affected by initial residual stress in the process of UAV structural components processing. Because machining errors are easy to occur, an optimization model for machining parameters of UAV integral structural components based on yield response is proposed. The finite element method is used to simulate the machining parameters of UAV integral structural components. The prediction model of workpiece surface machining error is established, and the influence of the path of walking knife on residual stress of UAV integral structure is studied, according to the stress of UAV integral component. The yield response of the time-varying stiffness is analyzed, and the yield response and the stress evolution mechanism of the UAV integral structure are analyzed. The simulation results show that this method is used to optimize the machining parameters of UAV integral structural components and improve the precision of UAV milling processing. The machining error is reduced, and the deformation prediction and error compensation of UAV integral structural parts are realized, thus improving the quality of machining.

40 CFR 23.8 - Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. 23.8 Section 23.8 Protection of Environment... Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. Unless the Administrator...

40 CFR 23.8 - Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. 23.8 Section 23.8 Protection of Environment... Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. Unless the Administrator...

40 CFR 23.8 - Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. 23.8 Section 23.8 Protection of Environment... Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. Unless the Administrator...

40 CFR 23.8 - Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. 23.8 Section 23.8 Protection of Environment... Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. Unless the Administrator...

40 CFR 23.8 - Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Timing of Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. 23.8 Section 23.8 Protection of Environment... Administrator's action under Uranium Mill Tailings Radiation Control Act of 1978. Unless the Administrator...

Direct Machining of Low-Loss THz Waveguide Components With an RF Choke.

PubMed

Lewis, Samantha M; Nanni, Emilio A; Temkin, Richard J

2014-12-01

We present results for the successful fabrication of low-loss THz metallic waveguide components using direct machining with a CNC end mill. The approach uses a split-block machining process with the addition of an RF choke running parallel to the waveguide. The choke greatly reduces coupling to the parasitic mode of the parallel-plate waveguide produced by the split-block. This method has demonstrated loss as low as 0.2 dB/cm at 280 GHz for a copper WR-3 waveguide. It has also been used in the fabrication of 3 and 10 dB directional couplers in brass, demonstrating excellent agreement with design simulations from 240-260 GHz. The method may be adapted to structures with features on the order of 200 μm.

Failure study of helium-cooled tungsten divertor plasma-facing units tested at DEMO relevant steady-state heat loads

NASA Astrophysics Data System (ADS)

Ritz, G.; Hirai, T.; Norajitra, P.; Reiser, J.; Giniyatulin, R.; Makhankov, A.; Mazul, I.; Pintsuk, G.; Linke, J.

2009-12-01

Tungsten was selected as armor material for the helium-cooled divertor in future DEMO-type fusion reactors and fusion power plants. After realizing the design and testing of them under cyclic thermal loads of up to ~14 MW m-2, the tungsten divertor plasma-facing units were examined by metallography; they revealed failures such as cracks at the thermal loaded and as-machined surfaces, as well as degradation of the brazing layers. Furthermore, in order to optimize the machining processes, the quality of tungsten surfaces prepared by turning, milling and using a diamond cutting wheel were examined. This paper presents a metallographic examination of the tungsten plasma-facing units as well as technical studies and the characterization on machining of tungsten and alternative brazing joints.

Fit of interim crowns fabricated using photopolymer-jetting 3D printing.

PubMed

Mai, Hang-Nga; Lee, Kyu-Bok; Lee, Du-Hyeong

2017-08-01

The fit of interim crowns fabricated using 3-dimensional (3D) printing is unknown. The purpose of this in vitro study was to evaluate the fit of interim crowns fabricated using photopolymer-jetting 3D printing and to compare it with that of milling and compression molding methods. Twelve study models were fabricated by making an impression of a metal master model of the mandibular first molar. On each study model, interim crowns (N=36) were fabricated using compression molding (molding group, n=12), milling (milling group, n=12), and 3D polymer-jetting methods. The crowns were prepared as follows: molding group, overimpression technique; milling group, a 5-axis dental milling machine; and polymer-jetting group using a 3D printer. The fit of interim crowns was evaluated in the proximal, marginal, internal axial, and internal occlusal regions by using the image-superimposition and silicone-replica techniques. The Mann-Whitney U test and Kruskal-Wallis tests were used to compare the results among groups (α=.05). Compared with the molding group, the milling and polymer-jetting groups showed more accurate results in the proximal and marginal regions (P<.001). In the axial regions, even though the mean discrepancy was smallest in the molding group, the data showed large deviations. In the occlusal region, the polymer-jetting group was the most accurate, and compared with the other groups, the milling group showed larger internal discrepancies (P<.001). Polymer-jet 3D printing significantly enhanced the fit of interim crowns, particularly in the occlusal region. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Preparation of Si nano-crystals with controlled oxidation state from SiO disproportionated by ZrO2 ball-milling

NASA Astrophysics Data System (ADS)

Okamoto, Yuji; Harada, Yoshitomo; Ohta, Narumi; Takada, Kazunori; Sumiya, Masatomo

2016-09-01

We demonstrate that a SiO disproportionation reaction can be achieved simply by high energy mechanochemical milling. The planetary ball-milling of ZrO2 for a few minutes generated Si nano-crystals. Milling conditions including rotation speed, ball number, milling time, and type of ball material were able to control the oxidation states of Si. The ball-milled SiO powder was tested as an anode of a lithium battery. ZrO2 contamination from the vial and balls was eliminated by dipping the ball-milled SiO powder in (NH4)HSO4 molten salt and heating for 5 min. The disproportionated SiO powder showed characteristics comparable to those of a powder prepared by a conventional heating process taking several hours.

Investigation on Effect of Material Hardness in High Speed CNC End Milling Process.

PubMed

Dhandapani, N V; Thangarasu, V S; Sureshkannan, G

2015-01-01

This research paper analyzes the effects of material properties on surface roughness, material removal rate, and tool wear on high speed CNC end milling process with various ferrous and nonferrous materials. The challenge of material specific decision on the process parameters of spindle speed, feed rate, depth of cut, coolant flow rate, cutting tool material, and type of coating for the cutting tool for required quality and quantity of production is addressed. Generally, decision made by the operator on floor is based on suggested values of the tool manufacturer or by trial and error method. This paper describes effect of various parameters on the surface roughness characteristics of the precision machining part. The prediction method suggested is based on various experimental analysis of parameters in different compositions of input conditions which would benefit the industry on standardization of high speed CNC end milling processes. The results show a basis for selection of parameters to get better results of surface roughness values as predicted by the case study results.

Study on Finite Element Method of Stress Field in Aluminum Alloy High-Speed Milling Process

NASA Astrophysics Data System (ADS)

Zhang, Wei; Li, Shunming; Wu, Qijun; An, Zenghui

2017-11-01

Three-dimensional numerical simulation model has been built by means of Advantage FEM. Perform simulation the stress fields of 7050-T7451 aluminum alloy in high speed milling process at the speed range of 628 m/min∼5946 m/min. The dynamic change and speed’s influence of stress fields and residual stress in machined layer is systematically analyzed. Some conclusions were drawn. With the cutting process development, the stress field converts to the stress state that crushing stress occupies a leading position. The magnitudes of crushing stress in all directions reduce with milling processes as the effect of Thermal-Mechanical-Coupled weakens; With the cutting speed increasing the magnitudes of crushing stress in all directions fluctuate near -950Mpa first, and then increase at the speed of 3000m/min; The residual pulling stress beneath the surface 0.03mm has been found and the magnitude increases with the cutting speed. A good agreement was obtained between predictions and experiments.

Investigation on Effect of Material Hardness in High Speed CNC End Milling Process

PubMed Central

Dhandapani, N. V.; Thangarasu, V. S.; Sureshkannan, G.

2015-01-01

This research paper analyzes the effects of material properties on surface roughness, material removal rate, and tool wear on high speed CNC end milling process with various ferrous and nonferrous materials. The challenge of material specific decision on the process parameters of spindle speed, feed rate, depth of cut, coolant flow rate, cutting tool material, and type of coating for the cutting tool for required quality and quantity of production is addressed. Generally, decision made by the operator on floor is based on suggested values of the tool manufacturer or by trial and error method. This paper describes effect of various parameters on the surface roughness characteristics of the precision machining part. The prediction method suggested is based on various experimental analysis of parameters in different compositions of input conditions which would benefit the industry on standardization of high speed CNC end milling processes. The results show a basis for selection of parameters to get better results of surface roughness values as predicted by the case study results. PMID:26881267

Tool life and surface integrity aspects when drilling nickel alloy

NASA Astrophysics Data System (ADS)

Kannan, S.; Pervaiz, S.; Vincent, S.; Karthikeyan, R.

2018-04-01

Nickel based super alloys manufactured through powder metallurgy (PM) route are required to increase the operational efficiency of gas turbine engines. They are material of choice for high pressure components due to their superior high temperature strength, excellent corrosion, oxidation and creep resistance. This unique combination of mechanical and thermal properties makes them even more difficult-to-machine. In this paper, the hole making process using coated carbide inserts by drilling and plunge milling for a nickel-based powder metallurgy super alloy has been investigated. Tool life and process capability studies were conducted using optimized process parameters using high pressure coolants. The experimental trials were directed towards an assessment of the tendency for surface malformations and detrimental residual stress profiles. Residual stresses in both the radial and circumferential directions have been evaluated as a function of depth from the machined surface using the target strain gauge / center hole drilling method. Circumferential stresses near workpiece surface and at depth of 512 µm in the starting material was primarily circumferential compression which was measured to be average of –404 MPa. However, the radial stresses near workpiece surface was tensile and transformed to be compressive in nature at depth of 512 µm in the starting material (average: -87 Mpa). The magnitude and the depth below the machined surface in both radial and circumferential directions were primarily tensile in nature which increased with hole number due to a rise of temperature at the tool–workpiece interface with increasing tool wear. These profiles are of critical importance for the selection of cutting strategies to ensure avoidance/minimization of tensile residual stresses that can be detrimental to the fatigue performance of the components. These results clearly show a tendency for the circumferential stresses to be more tensile than the radial stresses. Overall the results indicate that the effect of drilling and milling parameters is most marked in terms of surface quality in the circumferential direction. Material removal rates and tool flank wear must be maintained within the control limits to maintain hole integrity.

Preliminary Testing of a Compact, Bone-Attached Robot for Otologic Surgery

PubMed Central

Dillon, Neal P.; Balachandran, Ramya; dit Falisse, Antoine Motte; Wanna, George B.; Labadie, Robert F.; Withrow, Thomas J.; Fitzpatrick, J. Michael; Webster, Robert J.

2014-01-01

Otologic surgery often involves a mastoidectomy procedure, in which part of the temporal bone is milled away in order to visualize critical structures embedded in the bone and safely access the middle and inner ear. We propose to automate this portion of the surgery using a compact, bone-attached milling robot. A high level of accuracy is required to avoid damage to vital anatomy along the surgical path, most notably the facial nerve, making this procedure well-suited for robotic intervention. In this study, several of the design considerations are discussed and a robot design and prototype are presented. The prototype is a 4 degrees-of-freedom robot similar to a four-axis milling machine that mounts to the patient’s skull. A positioning frame, containing fiducial markers and attachment points for the robot, is rigidly attached to the skull of the patient, and a CT scan is acquired. The target bone volume is manually segmented in the CT by the surgeon and automatically converted to a milling path and robot trajectory. The robot is then attached to the positioning frame and is used to drill the desired volume. The accuracy of the entire system (image processing, planning, robot) was evaluated at several critical locations within or near the target bone volume with a mean free space accuracy result of 0.50 mm or less at all points. A milling test in a phantom material was then performed to evaluate the surgical workflow. The resulting milled volume did not violate any critical structures. PMID:25477726

Modeling of process of forming quality parameters for surfaces of parts by diamond burnishing taking into account technological heredity

NASA Astrophysics Data System (ADS)

Nagorkin, M. N.; Fyodorov, V. P.; Kovalyova, E. V.

2018-03-01

The paper presents a methodology for quantitative assessment of the influence of technological heredity on the formation of quality parameters for surfaces of machine parts. An example of an estimation of influence factors of technological subsystems of processing by end milling processing by composite 10 and the subsequent diamond burnishing is presented.

Strategic Alliances: Making a Difference One Warfighter At a Time

DTIC Science & Technology

2011-03-12

Prototype Integration Planning Machining / CNC / Metals Welding Assembly / Paint Integration •Field-Experienced Veterans •Component, Subsystems...Wiring Harness •CAD/CAM CNC Programming •Quick reaction of parts - CNC , Lathes, Mills, Water Jet/Laser Cutting Design •Mechanical, Electrical...DEFORMATION RESISTANCE WELDING • Tubular Structural welding, Light weight structures COMBINED PLASMA -MIG ARC WELDING • Faster than any other

Development of the swathe-felling mobile chipper

Treesearch

P. Koch; T.E. Savage

1980-01-01

A harvesting machine and auxilary equipment are being developed to recover logging residues us chips for fuel and fiber, and to deliver these chips to mills at ubout $18 per green ton including 30 percent pre-tax profit on the equipment investment. The harvester, a 575 horsepower trucked mobile chipper equipped with a front-mounted felling bar, wus field-tested on red...

TACOM LCMC Industrial Base Networking Summit

DTIC Science & Technology

2010-03-25

CAD/CAM CNC Programming •Quick reaction of parts - CNC , Lathes , Mills, Water Jet/Laser Cutting Design •Mechanical, Electrical, Electronics...system that can efficiently fabricate standard and unique parts at the point of need • Lathe modules deployed at 4 strategic SWA locations • Concepts...Prototype Integration Planning Machining / CNC / Metals Welding Assembly / Paint Integration •Field-Experienced Veterans •Component, Subsystems

Method for milling and drilling glass

NASA Technical Reports Server (NTRS)

Rice, S. H. (Inventor)

1980-01-01

A process for machining glass by placing a rotating carbide working surface under minimum pressure against an area of glass to be worked is described. Concurrently the region between the working surface and the area of glass is wet with a lubricant consisting essentially of a petroleum carrier, a complex mixture of esters and a complex mixture of naturally occurring aromatic oils.

Vocational Rehabilitation of Young Adults with a Disability of One Arm or Hand.

ERIC Educational Resources Information Center

Nijboer, Irene D.; Wevers, Cornelius J.

1993-01-01

A work analysis was conducted to determine whether the job of lathe and milling machine operator is suitable for young adults with one arm or hand. The analysis concluded that it is suitable but adjustments of the workplace may be necessary, such as transporting heavy equipment. The importance of labor research to vocational rehabilitation is…

New developments in surface technology and prototyping

NASA Astrophysics Data System (ADS)

Himmer, Thomas; Beyer, Eckhard

2003-03-01

Novel lightweight applications in the automotive and aircraft industries require advanced materials and techniques for surface protection as well as direct and rapid manufacturing of the related components and tools. The manufacturing processes presented in this paper are based on multiple additive and subtractive technologies such as laser cutting, laser welding, direct laser metal deposition, laser/plasma hybrid spraying technique or CNC milling. The process chain is similar to layer-based Rapid Prototyping Techniques. In the first step, the 3D CAD geometry is sliced into layers by a specially developed software. These slices are cut by high speed laser cutting and then joined together. In this way laminated tools or parts are built. To improve surface quality and to increase wear resistance a CNC machining center is used. The system consists of a CNC milling machine, in which a 3 kW Nd:YAG laser, a coaxial powder nozzle and a digitizing system are integrated. Using a new laser/plasma hybrid spraying technique, coatings can be deposited onto parts for surface protection. The layers show a low porosity and high adhesion strength, the thickness is up to 0.3 mm, and the lower effort for preliminary surface preparation reduces time and costs of the whole process.

Fabrication of spherical mitigation pit on KH2PO4 crystal by micro-milling and modeling of its induced light intensification.

PubMed

Cheng, Jian; Chen, Mingjun; Liao, Wei; Wang, Haijun; Xiao, Yong; Li, Mingquan

2013-07-15

Micro-machining is the most promising method for KH(2)PO(4) crystal to mitigate the surface damage growth in high power laser system. In this work, spherical mitigation pit is fabricated by micro-milling with an efficient machining procedure. The light intensification caused by rear surface features before and after mitigation is numerically modeled based on the finite-difference time-domain method. The results indicate that the occurrence of total internal reflections should be responsible for the largest light intensification inside the crystal. For spherical pits after mitigation, the light intensification can be greatly alleviated by preventing the occurrence of total internal reflections. The light intensification caused by spherical mitigation pit is strongly dependent on the width-depth ratio and it is suggested that the width-depth ratio of spherical mitigation pit must be devised to be larger than 5.0 to achieve the minimal light intensification for the mitigation of surface damage growth. Laser damage tests for KH(2)PO(4) crystal validate that the laser damage resistance of initially damaged surface can be retrieved to near the level of ideal surface by replacing initial damage site with predesigned mitigation pit.

Description of photovoltaic village power systems in the United States and Africa

NASA Technical Reports Server (NTRS)

Ratajczak, A. F.; Bifano, W. J.

1979-01-01

Photovoltaic power systems in remote villages in the United States and Africa are described. These projects were undertaken to demonstrate that existing photovoltaic system technology is capable of providing electrical power for basic domestic services for the millions of small, remote communities in both developed and developing countries. One system is located in the Papago Indian Village of Schuchuli in southwest Arizona (U. S.) and became operational 16 December 1978. The other system is located in Tangaye, a rural village in Upper Volta, Africa. It became operational 1 March 1979. The Schuchuli system has a 3.5 kW (peak) solar array which provides electric power for village water pumping, a refrigerator for each family, lights in the village buildings, and a community washing machine and sewing machine. The 1.8 kW (peak) Tangaye system provides power for community water pumping, flour milling and lights in the milling building. These are both stand-alone systems (i.e., no back-up power source) which are being operated and maintained by local personnel. Both systems are instrumented. Systems operations are being monitored by NASA to measure design adequacy and to refine designs for future systems.

Description of photovoltaic village power systems in the United States and Africa

NASA Technical Reports Server (NTRS)

Ratajczak, A. F.; Bifano, W. J.

1979-01-01

The paper describes the designs, hardware, and installations of NASA photovoltaic power systems in the village of Schuchuli in Arizona and Tangaye in Upper Volta, Africa. The projects were designed to demonstrate that current photovoltaic system technology can provide electrical power for domestic services for small, remote communities. The Schuchuli system has a 3.5 kW peak solar array which provides power for water pumping, a refrigerator for each family, lights, and community washing and sewing machines. The 1.8 kW Tangaye system provides power for pumping, flour milling, and lights in the milling building. Both are stand-alone systems operated by local personnel, and they are monitored by NASA to measure design adequacy and refine future designs.

Study design and preliminary data analysis for a streambank fencing project in the Mill Creek Basin, Pennsylvania

USGS Publications Warehouse

Galeone, Daniel G.; Koerkle, Edward H.

1996-01-01

The Pequea Creek and Mill Creek Basins within Lancaster and Chester Counties in Pennsylvania have been identified as areas needing control of nonpoint-source (NFS) pollution to improve water quality. The two basins are a total of approximately 200 square miles and are primarily underlain by carbonate bedrock. Land use is predominantly agriculture. The most common agricultural NFS pollution-control practices implemented in the Pequea Creek and Mill Creek Basins are barnyard-runoff control and Streambank fencing. To provide land managers information on the effectiveness of Streambank fencing in controlling NFS pollution, a study is being conducted in two small paired watersheds within the Mill Creek Basin.

Investigation on the Acoustic Absorption of Flexible Micro-Perforated Panel with Ultra-Micro Perforations

NASA Astrophysics Data System (ADS)

Li, Guoxin; Tang, Xiaoning; Zhang, Xiaoxiao; Qian, Y. J.; Kong, Deyi

2017-11-01

Flexible micro-perforated panel has unique advantages in noise reduction due to its good flexibility compared with traditional rigid micro-perforated panel. In this paper, flexible micro-perforated panel was prepared by computer numerical control (CNC) milling machine. Three kinds of plastics including polyvinylchloride (PVC), polyethylene terephthalate (PET), and polyimide (PI) were taken as the matrix materials to prepare flexible micro-perforated panel. It has been found that flexible micro-perforated panel made of PET possessing good porosity and proper density, elastic modulus and poisson ratio exhibited the best acoustic absorption properties. The effects of various structural parameters including perforation diameter, perforation ratio, thickness and air gap have also been investigated, which would be helpful to the optimization of acoustic absorption properties.

KSC-98pc929

NASA Image and Video Library

1998-08-10

In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, holds down a curtain while making a test sample of tile on a block 5-axis computerized numerical control milling machine. About 70 percent of a Space Shuttle orbiter’s external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. They are known as High-Temperature Reusable Surface Insulation (HRSI) tiles and Low-Temperature Reusable Surface Insulation (LRSI) tiles. Most HRSI tiles are 6 inches square, but may be as large as 12 inches in some areas, and 1 to 5 inches thick. LRSI tiles are generally 8 inches square, ranging from 0.2to 1-inch thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter

Influence of cutting data on surface quality when machining 17-4 PH stainless steel

NASA Astrophysics Data System (ADS)

Popovici, T. D.; Dijmărescu, M. R.

2017-08-01

The aim of the research presented in this paper is to analyse the cutting data influence upon surface quality for 17-4 PH stainless steel milling machining. The cutting regime parameters considered for the experiments were established using cutting regimes from experimental researches or from industrial conditions as basis, within the recommended ranges. The experimental program structure was determined by taking into account compatibility and orthogonality conditions, minimal use of material and labour. The machined surface roughness was determined by measuring the Ra roughness parameter, followed by surface profile registration in the form of graphics which were saved on a computer with MarSurf PS1Explorer software. Based on Ra roughness parameter, maximum values were extracted from these graphics and the influence charts of the cutting regime parameters upon surface roughness were traced using Microsoft Excel software. After a thorough analysis of the resulting data, relevant conclusions were drawn, presenting the interdependence between the surface roughness of the machined 17-4 PH samples and the cutting data variation.

Additively Manufactured Titanium and Cobalt-Chromium Implant Frameworks: Fit and Effect of Ceramic Veneering.

PubMed

Svanborg, Per; Eliasson, Alf; Stenport, Victoria

The purpose of this study was to evaluate the fit of additively manufactured cobalt-chromium and titanium and CNC-milled titanium frameworks before and after ceramic veneering. Ten stone casts simulating an edentulous maxilla provided with six abutment analogs were produced. For each stone cast, one additively manufactured cobalt-chromium framework (AM CoCr) and one titanium framework (AM Ti) were fabricated. The fit was analyzed with a coordinate measuring machine in three dimensions (x, y, and z axes) using best-fit virtual matching of center point coordinates, before and after ceramic veneering. CNC-milled titanium frameworks (CNC Ti) and earlier results from CNC-milled cobalt-chromium frameworks (CNC CoCr) were used for comparison. All frameworks presented minor misfit before and after veneering in the horizontal plane (x- and y-axes) between 2.9 and 13.5 μm and in the vertical plane (z-axis) between 1.6 and 5.4 μm. Ceramic veneering affected the fit of all groups of frameworks. Both AM Ti and AM CoCr presented significantly smaller distortion in the vertical plane compared with the CNC-milled frameworks. Implant-supported frameworks can be produced in either Ti or CoCr using either CNC milling or additive manufacturing with a fit well within the range of 20 μm in the horizontal plane and 10 μm in the vertical plane. The fit of frameworks of both materials and production techniques are affected by the ceramic veneering procedure to a small extent.

28. MESTA STEAM ENGINE, INSTALLED BY THE CORRIGAN, McKINNEY COMPANY ...

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

28. MESTA STEAM ENGINE, INSTALLED BY THE CORRIGAN, McKINNEY COMPANY IN 1916, STILL DRIVES THE 44-INCH REVERSING BLOOMING MILL. THE TWIN TANDAM, COMPOUND CONDENSING, REVERSING STEAM ENGINE HAS A RATED CAPACITY OF 35,000 H.P. IT WAS BUILT BY THE MESTA MACHINE COMPANY OF PITTSBURGH. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

BRASS FOUNDRY ROOM SHOWING GATE CUTTERS USED TO REMOVE RUNNERS ...

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

BRASS FOUNDRY ROOM SHOWING GATE CUTTERS USED TO REMOVE RUNNERS AND SPRUES FROM BRONZE CASTINGS TOO SOFT TO BE CLEANED IN TUMBLING MILLS. ALSO SHOWN ARE MOLD MACHINES AND THE SAND DELIVERY SYSTEM USED TO CREATE GREEN SAND MOLDS, POURED AT THE OTHER END OF THE GRAVITY CONVEYORS. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

Uranium and radium concentrations in plants growing on uranium mill tailings in South Dakota

Treesearch

Mark A. Rumble; Ardell J. Bjugstad

1986-01-01

Vegetation and soil samples were collected from a uranium mill tailings site and control sites in South Dakota. Uranium concentrations in soils from the mill tailings averaged 13.3 [micro]g g-1 compared to 5.1 [micro]g g-1 in soils from control sites. 226Ra concentrations in soils averaged 111.0 pCi g...

75 FR 26794 - International Paper Company Franklin Pulp & Paper Mill Including On-Site Leased Workers From...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-12

... Company Franklin Pulp & Paper Mill Including On-Site Leased Workers From Railserve, Franklin, VA; Amended... workers of International Paper Company, Franklin Pulp & Paper Mill, Franklin, Virginia. The notice was... Pulp & Paper Mill. The Department has determined that these workers were sufficiently under the control...

Study on the Preparation Process and Influential Factors of Large Area Environment-friendly Molten Carbonate Fuel Cell Matrix

NASA Astrophysics Data System (ADS)

Zhang, Ruiyun; Xu, Shisen; Cheng, Jian; Wang, Hongjian; Ren, Yongqiang

2017-07-01

Low-cost and high-performance matrix materials used in mass production of molten carbonate fuel cell (MCFC) were prepared by automatic casting machine with α-LiAlO2 powder material synthesized by gel-solid method, and distilled water as solvent. The single cell was assembled for generating test, and the good performance of the matrix was verified. The paper analyzed the factors affecting aqueous tape casting matrix preparation, such as solvent content, dispersant content, milling time, blade height and casting machine running speed, providing a solid basis for the mass production of large area environment-friendly matrix used in molten carbonate fuel cell.

INTERIOR OVERVIEW OF CONTINUOUS CASTER WITH NO. 12 LADLE. MOLTEN ...

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

INTERIOR OVERVIEW OF CONTINUOUS CASTER WITH NO. 12 LADLE. MOLTEN STEEL IS POURED FROM LADLE THROUGH SHROUD TO TUNDISH. FROM TUNDISH STEEL ENTERS MOLD THROUGH SHROUD AND FORMATION OF SLAB SHELL BEGINS. AS SLAB PROGRESSES THROUGH CONTAINMENT SECTION IT IS COOLED WITH AIR MIST SPRAYS AND CONTINUES SOLIDIFICATION. UPON EXITING THE MACHINE THE SLABS ARE CUT TO DESIRED LENGTH AND IDENTIFIED. THE SLABS ARE STACKED, REMOVED FROM MACHINE AND PREPARED FOR SHIPMENT TO HOT STRIP MILL. CASTER HAS ABILITY TO PRODUCE SINGLE OR TWIN CASTS. SINGLE SLABS PRODUCED MAY BE UP TO 102 INCHES; DOUBLE SLABS UP TO 49 INCHES. - U.S. Steel, Fairfield Works, Continuous Caster, Fairfield, Jefferson County, AL

Innovative production technology in aircraft construction: CIAM Forming 'made by MBB' - A highly productive example

NASA Astrophysics Data System (ADS)

A novel production technology in aircraft construction was developed for manufacturing parts of shapes and dimensions that involve only small quantities for one machine. The process, called computerized integrated and automated manufacturing (CIAM), makes it possible to make ready-to-install sheet-metal parts for all types of aircraft. All of the system's job sequences, which include milling the flat sheet-metal parts in stacks, deburring, heat treatment, and forming under the high-pressure rubber-pad press, are automated. The CIAM production center, called SIAM Forming, fulfills the prerequisites for the cost-effective production of sheet-metal parts made of aluminum alloys, titanium, or steel. The SIAM procedure results in negligible material loss through computerizing both component-contour nesting of the sheet-metal parts and contour milling.

24. The DryingRoom in the coating mill at Lawrence, Mass. ...

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

24. The Drying-Room in the coating mill at Lawrence, Mass. After the paper has received its coating from the coating-machine shown in the previous picture, it passes in a continuous web to the drying-room. Blasts of hot air coming out of galvanized ducts beneath support it for a distance of 100 feet, until it reaches the drying-chamber in the rear of the room. Here it hangs in festoons much like those of cotton cloth shown on page 219. In the picture the paper is passing from right to left. After leaving the drying-room it is wound on rolls, as shown in the next picture. (p.238.) - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

Operational stability prediction in milling based on impact tests

NASA Astrophysics Data System (ADS)

Kiss, Adam K.; Hajdu, David; Bachrathy, Daniel; Stepan, Gabor

2018-03-01

Chatter detection is usually based on the analysis of measured signals captured during cutting processes. These techniques, however, often give ambiguous results close to the stability boundaries, which is a major limitation in industrial applications. In this paper, an experimental chatter detection method is proposed based on the system's response for perturbations during the machining process, and no system parameter identification is required. The proposed method identifies the dominant characteristic multiplier of the periodic dynamical system that models the milling process. The variation of the modulus of the largest characteristic multiplier can also be monitored, the stability boundary can precisely be extrapolated, while the manufacturing parameters are still kept in the chatter-free region. The method is derived in details, and also verified experimentally in laboratory environment.

Surface acquisition through virtual milling

NASA Technical Reports Server (NTRS)

Merriam, Marshal L.

1993-01-01

Surface acquisition deals with the reconstruction of three dimensional objects from a set of data points. The most straightforward techniques require human intervention, a time consuming proposition. It is desirable to develop a fully automated alternative. Such a method is proposed in this paper. It makes use of surface measurements obtained from a 3-D laser digitizer - an instrument which provides the (x,y,z) coordinates of surface data points from various viewpoints. These points are assembled into several partial surfaces using a visibility constraint and a 2-D triangulation technique. Reconstruction of the final object requires merging these partial surfaces. This is accomplished through a procedure that emulates milling, a standard machining operation. From a geometrical standpoint the problem reduces to constructing the intersection of two or more non-convex polyhedra.

Optimization of Machining Parameters of Milling Operation by Application of Semi-synthetic oil based Nano cutting Fluids

NASA Astrophysics Data System (ADS)

Giri Prasad, M. J.; Abhishek Raaj, A. S.; Rishi Kumar, R.; Gladson, Frank; M, Gautham

2016-09-01

The present study is concerned with resolving the problems pertaining to the conventional cutting fluids. Two samples of nano cutting fluids were prepared by dispersing 0.01 vol% of MWCNTs and a mixture of 0.01 vol% of MWCNTs and 0.01 vol% of nano ZnO in the soluble oil. The thermophysical properties such as the kinematic viscosity, density, flash point and the tribological properties of the prepared nano cutting fluid samples were experimentally investigated and were compared with those of plain soluble oil. In addition to this, a milling process was carried by varying the process parameters and by application of different samples of cutting fluids and an attempt was made to determine optimal cutting condition using the Taguchi optimization technique.

Computerized Design of Low-noise Face-milled Spiral Bevel Gears

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Zhang, YI; Handschuh, Robert F.

1994-01-01

An advanced design methodology is proposed for the face-milled spiral bevel gears with modified tooth surface geometry that provides a reduced level of noise and has a stabilized bearing contact. The approach is based on the local synthesis of the gear drive that provides the 'best' machine-tool settings. The theoretical aspects of the local synthesis approach are based on the application of a predesigned parabolic function for absorption of undesirable transmission errors caused by misalignment and the direct relations between principal curvatures and directions for mating surfaces. The meshing and contact of the gear drive is synthesized and analyzed by a computer program. The generation of gears with the proposed geometry design can be accomplished by application of existing equipment. A numerical example that illustrates the proposed theory is presented.

Computerized design of low-noise face-milled spiral bevel gears

NASA Astrophysics Data System (ADS)

Litvin, Faydor L.; Zhang, Yi; Handschuh, Robert F.

1994-08-01

An advanced design methodology is proposed for the face-milled spiral bevel gears with modified tooth surface geometry that provides a reduced level of noise and has a stabilized bearing contact. The approach is based on the local synthesis of the gear drive that provides the 'best' machine-tool settings. The theoretical aspects of the local synthesis approach are based on the application of a predesigned parabolic function for absorption of undesirable transmission errors caused by misalignment and the direct relations between principal curvatures and directions for mating surfaces. The meshing and contact of the gear drive is synthesized and analyzed by a computer program. The generation of gears with the proposed geometry design can be accomplished by application of existing equipment. A numerical example that illustrates the proposed theory is presented.

Thermal modeling and analysis of thin-walled structures in micro milling

NASA Astrophysics Data System (ADS)

Zhang, J. F.; Ma, Y. H.; Feng, C.; Tang, W.; Wang, S.

2017-11-01

The numerical analytical model has been developed to predict the thermal effect with respect to thin walled structures by micro-milling. In order to investigate the temperature distribution around micro-edge of cutter, it is necessary to considering the friction power, the shearing power, the shear area between the tool micro-edge and materials. Due to the micro-cutting area is more difficult to be measured accurately, the minimum chip thickness as one of critical factors is also introduced. Finite element-based simulation was employed by the Advantedge, which was determined from the machining of Ti-6Al-4V over a range of the uncut chip thicknesses. Results from the proposed model have been successfully accounted for the effects of thermal softening for material.

Estimation of tool wear length in finish milling using a fuzzy inference algorithm

NASA Astrophysics Data System (ADS)

Ko, Tae Jo; Cho, Dong Woo

1993-10-01

The geometric accuracy and surface roughness are mainly affected by the flank wear at the minor cutting edge in finish machining. A fuzzy estimator obtained by a fuzzy inference algorithm with a max-min composition rule to evaluate the minor flank wear length in finish milling is introduced. The features sensitive to minor flank wear are extracted from the dispersion analysis of a time series AR model of the feed directional acceleration of the spindle housing. Linguistic rules for fuzzy estimation are constructed using these features, and then fuzzy inferences are carried out with test data sets under various cutting conditions. The proposed system turns out to be effective for estimating minor flank wear length, and its mean error is less than 12%.

Health hazard evaluation report HETA 85-039-1723, E. L. Smithe Machine Company, Duncansville, Pennsylvania

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

Bennett, D.E.

1986-08-01

The International Association of Machinists Local 2348 requested an investigation of reported skin rashes and headaches associated with cutting and cooling oils and solvents used in the machine shop. Of 62 employees interviewed, 42 had experienced skin problems occurring on their hands and arms including red skin, dry skin, cracked skin, or itchy skin, related to chemical exposures at the workplace. Xerosis, lichenification, or eczema of the hands and arms were noted on examination of 17 employees of the Lathe Department and 18 of those from the Milling Department. Respiratory and neurological complaints were also found among these employees. Themore » author concluded that the incidence of hand and arm xerosis and eczema in workers in the machining area may be associated with exposure to cutting oils. The author recommends that changes be made to minimize skin exposure and provide adequate ventilation and humidification.« less

Fracture Tests of Etched Components Using a Focused Ion Beam Machine

NASA Technical Reports Server (NTRS)

Kuhn, Jonathan, L.; Fettig, Rainer K.; Moseley, S. Harvey; Kutyrev, Alexander S.; Orloff, Jon; Powers, Edward I. (Technical Monitor)

2000-01-01

Many optical MEMS device designs involve large arrays of thin (0.5 to 1 micron components subjected to high stresses due to cyclic loading. These devices are fabricated from a variety of materials, and the properties strongly depend on size and processing. Our objective is to develop standard and convenient test methods that can be used to measure the properties of large numbers of witness samples, for every device we build. In this work we explore a variety of fracture test configurations for 0.5 micron thick silicon nitride membranes machined using the Reactive Ion Etching (RIE) process. Testing was completed using an FEI 620 dual focused ion beam milling machine. Static loads were applied using a probe. and dynamic loads were applied through a piezo-electric stack mounted at the base of the probe. Results from the tests are presented and compared, and application for predicting fracture probability of large arrays of devices are considered.

Laser processing of ceramics for microelectronics manufacturing

NASA Astrophysics Data System (ADS)

Sposili, Robert S.; Bovatsek, James; Patel, Rajesh

2017-03-01

Ceramic materials are used extensively in the microelectronics, semiconductor, and LED lighting industries because of their electrically insulating and thermally conductive properties, as well as for their high-temperature-service capabilities. However, their brittleness presents significant challenges for conventional machining processes. In this paper we report on a series of experiments that demonstrate and characterize the efficacy of pulsed nanosecond UV and green lasers in machining ceramics commonly used in microelectronics manufacturing, such as aluminum oxide (alumina) and aluminum nitride. With a series of laser pocket milling experiments, fundamental volume ablation rate and ablation efficiency data were generated. In addition, techniques for various industrial machining processes, such as shallow scribing and deep scribing, were developed and demonstrated. We demonstrate that lasers with higher average powers offer higher processing rates with the one exception of deep scribes in aluminum nitride, where a lower average power but higher pulse energy source outperformed a higher average power laser.

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

Selamat, Mohd Zulkefli, E-mail: azulkeflis@utem.edu.my; Yusuf, Muhammad Yusri Md, E-mail: yusri.cheras@gmail.com; Wer, Tio Kok, E-mail: to91@hotmail.my

Bipolar plates are key components in Proton Exchange Membrane (PEM) fuel cells. They carry current away from the cell and withstand the clamping force of the stack assembly. Therefore, PEM fuel cell bipolar plates must have high electrical conductivity and adequate mechanical strength, in addition to being light weight and low cost in terms of both applicable materials and production methods. In this research, the raw materials used to fabricate the high performance bipolar plate are Graphite (Gr), Stannum (Sn) and Polypropylene (PP). All materials used was in powder form and Gr and Sn act as fillers and the PPmore » acts as binder. The ratio of fillers (Gr/Sn) and binder (PP) was fixed at 80:20. For the multi-conductive filler, small amount of Sn, which is 10 up to 20wt% (from the total weight of fillers 80%) have been added into Gr/Sn/PP composite. The fillers were mixed by using the ball mill machine. The second stage of mixing process between the mixer of fillers and binder is also carried out by using ball mill machine before the compaction process by the hot press machine. The effect of formation temperatures (160°C-170°C) on the properties of Gr/Sn/PP composite had been studied in detail, especially the electrical conductivity, bulk density, hardness and microstructure analysis of Gr/Sn/PP composite. The result shows that there are significant improvement in the electrical conductivity and bulk density, which are exceeding the US-DoE target with the maximum value of 265.35 S/cm and 1.682g/cm{sup 3} respectively.« less

17. Woodworking Mill (basement): view looking north showing Ames Iron ...

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

17. Woodworking Mill (basement): view looking north showing Ames Iron Works steam boiler; note turbine control handle in middle right of photo - Ben Thresher's Mill, State Aid No. 1, Barnet, Caledonia County, VT

TiO2 gas sensor to detect the propanol at room temperature

NASA Astrophysics Data System (ADS)

Gaidan, Ibrahim; Asbia, Salim; Brabazon, Dermot; Ahad, Inam Ul

2017-10-01

Titanium dioxide (TiO2) was used as raw material to create sensing materials for gas sensor applications. The sample was mixed with isopropanol and wet-ball milled for 24 hours and then dried at 120°C to evaporate the solvent. Twenty grams of the dried powder was then pressed at 2 tons (27.58 MPa) using a pellet die. The pellet was heated at 1250°C in air for 5 hours and then milled for 10 minutes to powder form using a Gy-RO Mill machine. FIB and SEM analysis were used to study the microstructure of the materials. The polyvinyl butyral (5 wt.%) was used as a binder, while ethylenglycolmonobutylether served as a solvent to make a suitable paste. The paste was screen-printed on top of an alumina substrate that had copper electrodes to form the sensor. The sensor was used to detect propanol at room temperature over two different ranges (500 to 3000 ppm and 2500 to 5000 ppm). It was observed that the response of the device increased proportionally with increasing gas concentration repeatability.

An investigation into the design and performance of an automatic shape control system for a Sendzimir cold rolling mill

NASA Astrophysics Data System (ADS)

Dutton, Kenneth

Shape (or flatness) control for rolled steel strip is becoming increasingly important as customer requirements become more stringent. Automatic shape control is now more or less mandatory on all new four-high cold mills, but no comprehensive scheme yet exists on a Sendzimir mill. This is due to the complexity of the control system design on such a mill, where many more degrees of freedom for control exist than is the case with the four-high mills.The objective of the current work is to develop, from first principles, such a system; including automatic control of the As-U-Roll and first intermediate roll actuators in response to the measured strip shape. This thesis concerns itself primarily with the As-U-Roll control system. The material presented is extremely wide-ranging. Areas covered include the development of original static and dynamic mathematical models of the mill systems, and testing of the plant by data-logging to tune these models. A basic control system philosophy proposed by other workers is modified and developed to suit the practical system requirements and the data provided by the models. The control strategy is tested by comprehensive multivariable simulation studies. Finally, details are given of the practical problems faced when installing the system on the plant. These include problems of manual control inter-action bumpless transfer and integral desaturation.At the time of presentation of the thesis, system commissioning is still in progress and production results are therefore not yet available. Nevertheless, the simulation studies predict a successful outcome, although performance is expected to be limited until the first intermediate roll actuators are eventually included in the scheme also.

Surface structuring of boron doped CVD diamond by micro electrical discharge machining

NASA Astrophysics Data System (ADS)

Schubert, A.; Berger, T.; Martin, A.; Hackert-Oschätzchen, M.; Treffkorn, N.; Kühn, R.

2018-05-01

Boron doped diamond materials, which are generated by Chemical Vapor Deposition (CVD), offer a great potential for the application on highly stressed tools, e. g. in cutting or forming processes. As a result of the CVD process rough surfaces arise, which require a finishing treatment in particular for the application in forming tools. Cutting techniques such as milling and grinding are hardly applicable for the finish machining because of the high strength of diamond. Due to its process principle of ablating material by melting and evaporating, Electrical Discharge Machining (EDM) is independent of hardness, brittleness or toughness of the workpiece material. EDM is a suitable technology for machining and structuring CVD diamond, since boron doped CVD diamond is electrically conductive. In this study the ablation characteristics of boron doped CVD diamond by micro electrical discharge machining are investigated. Experiments were carried out to investigate the influence of different process parameters on the machining result. The impact of tool-polarity, voltage and discharge energy on the resulting erosion geometry and the tool wear was analyzed. A variation in path overlapping during the erosion of planar areas leads to different microstructures. The results show that micro EDM is a suitable technology for finishing of boron doped CVD diamond.

Influence of Cutting Parameters and Tool Wear on the Surface Integrity of Cobalt-Based Stellite 6 Alloy When Machined Under a Dry Cutting Environment

NASA Astrophysics Data System (ADS)

Yingfei, Ge; de Escalona, Patricia Muñoz; Galloway, Alexander

2017-01-01

The efficiency of a machining process can be measured by evaluating the quality of the machined surface and the tool wear rate. The research reported herein is mainly focused on the effect of cutting parameters and tool wear on the machined surface defects, surface roughness, deformation layer and residual stresses when dry milling Stellite 6, deposited by overlay on a carbon steel surface. The results showed that under the selected cutting conditions, abrasion, diffusion, peeling, chipping and breakage were the main tool wear mechanisms presented. Also the feed rate was the primary factor affecting the tool wear with an influence of 83%. With regard to the influence of cutting parameters on the surface roughness, the primary factors were feed rate and cutting speed with 57 and 38%, respectively. In addition, in general, as tool wear increased, the surface roughness increased and the deformation layer was found to be influenced more by the cutting parameters rather than the tool wear. Compressive residual stresses were observed in the un-machined surface, and when machining longer than 5 min, residual stress changed 100% from compression to tension. Finally, results showed that micro-crack initiation was the main mechanism for chip formation.

Vibration Damping Response of Composite Materials

DTIC Science & Technology

1991-04-01

using a diamond-impregnated cutoff wheel mounted on a milling machine . This procedure was followed to minimize damage to the composite specimens prior to...Development Report Vibration Damping Response of Composite Materials by Roger M. Crane 0E DTIC0 • ELECTE 16 - MAY 28 19914S8 0 E 5; 91--00524 Approved for...Damping Response of Composite Materials by Roger M. Crane TABLE OF CONTENTS Page LIST OF TABLES

USSR Report Machine Tools and Metalworking Equipment.

DTIC Science & Technology

1986-04-22

directors decided to teach the Bulat a new trade. This generator is now used to strengthen high-speed cutting mills by hardening them in a medium of...modules (GPM) and flexible production complexes ( GPK ). The flexible automated line is usually used for mass production of components. Here the...of programmable coordinates (x^ithout grip) 5 4 Method of programming teaching Memory capacity of robot system, points 300 Positioning error, mm

Formability behavior studies on CP-Al sheets processed through the helical tool path of incremental forming process

NASA Astrophysics Data System (ADS)

Markanday, H.; Nagarajan, D.

2018-02-01

Incremental sheet forming (ISF) is a novel die-less sheet metal forming process, which can produce components directly from the CAD geometry using a CNC milling machine at less production time and cost. The formability of the sheet material used is greatly affected by the process parameters involved and tool path adopted, and the present study is aimed to investigate the influence of different process parameter values using the helical tool path strategy on the formability of a commercial pure Al and to achieve maximum formability in the material. ISF experiments for producing an 80 mm diameter axisymmetric dome were carried out on 2 mm thickness commercially pure Al sheets for different tool speeds and feed rates in a CNC milling machine with a 10 mm hemispherical forming tool. The obtained parts were analyzed for springback, amount of thinning and maximum forming depth. The results showed that when the tool speed was increased by keeping the feed rate constant, the forming depth and thinning were also increased. On contrary, when the feed rate was increased by keeping the tool speed constant, the forming depth and thinning were decreased. Springback was found to be higher when the feed rate was increased rather than the tool speed was increased.

Determination of the cutting forces regression functions for milling machining of the X105CrMo17 material

NASA Astrophysics Data System (ADS)

Popovici, T. D.; Dijmărescu, M. R.

2017-08-01

The aim of the research presented in this paper is to determine a cutting force prediction model for milling machining of the X105CrMo17 stainless steel. The analysed material is a martensitic stainless steel which, due to the high Carbon content (∼1%) and Chromium (∼17%), has high hardness and good corrosion resistance characteristics. This material is used for the steel structures parts which are subject of wear in corrosive environments, for making valve seats, bearings, various types of cutters, high hardness bushings, casting shells and nozzles, measuring instruments, etc. The paper is structured into three main parts in accordance to the considered research program; they are preceded by an introduction and followed by relevant conclusions. In the first part, for a more detailed knowledge of the material characteristics, a quality and quantity micro-analysis X-ray and a spectral analysis were performed. The second part presents the physical experiment in terms of input, necessary means, process and registration of the experimental data. In the third part, the experimental data is analysed and the cutting force model is developed in terms of the cutting regime parameters such as cutting speed, feed rate, axial depth and radial depth.

Machinability of IPS Empress 2 framework ceramic.

PubMed

Schmidt, C; Weigl, P

2000-01-01

Using ceramic materials for an automatic production of ceramic dentures by CAD/CAM is a challenge, because many technological, medical, and optical demands must be considered. The IPS Empress 2 framework ceramic meets most of them. This study shows the possibilities for machining this ceramic with economical parameters. The long life-time requirement for ceramic dentures requires a ductile machined surface to avoid the well-known subsurface damages of brittle materials caused by machining. Slow and rapid damage propagation begins at break outs and cracks, and limits life-time significantly. Therefore, ductile machined surfaces are an important demand for machine dental ceramics. The machining tests were performed with various parameters such as tool grain size and feed speed. Denture ceramics were machined by jig grinding on a 5-axis CNC milling machine (Maho HGF 500) with a high-speed spindle up to 120,000 rpm. The results of the wear test indicate low tool wear. With one tool, you can machine eight occlusal surfaces including roughing and finishing. One occlusal surface takes about 60 min machining time. Recommended parameters for roughing are middle diamond grain size (D107), cutting speed v(c) = 4.7 m/s, feed speed v(ft) = 1000 mm/min, depth of cut a(e) = 0.06 mm, width of contact a(p) = 0.8 mm, and for finishing ultra fine diamond grain size (D46), cutting speed v(c) = 4.7 m/s, feed speed v(ft) = 100 mm/min, depth of cut a(e) = 0.02 mm, width of contact a(p) = 0.8 mm. The results of the machining tests give a reference for using IPS Empress(R) 2 framework ceramic in CAD/CAM systems. Copyright 2000 John Wiley & Sons, Inc.

Virtual Manufacturing Techniques Designed and Applied to Manufacturing Activities in the Manufacturing Integration and Technology Branch

NASA Technical Reports Server (NTRS)

Shearrow, Charles A.

1999-01-01

One of the identified goals of EM3 is to implement virtual manufacturing by the time the year 2000 has ended. To realize this goal of a true virtual manufacturing enterprise the initial development of a machinability database and the infrastructure must be completed. This will consist of the containment of the existing EM-NET problems and developing machine, tooling, and common materials databases. To integrate the virtual manufacturing enterprise with normal day to day operations the development of a parallel virtual manufacturing machinability database, virtual manufacturing database, virtual manufacturing paradigm, implementation/integration procedure, and testable verification models must be constructed. Common and virtual machinability databases will include the four distinct areas of machine tools, available tooling, common machine tool loads, and a materials database. The machine tools database will include the machine envelope, special machine attachments, tooling capacity, location within NASA-JSC or with a contractor, and availability/scheduling. The tooling database will include available standard tooling, custom in-house tooling, tool properties, and availability. The common materials database will include materials thickness ranges, strengths, types, and their availability. The virtual manufacturing databases will consist of virtual machines and virtual tooling directly related to the common and machinability databases. The items to be completed are the design and construction of the machinability databases, virtual manufacturing paradigm for NASA-JSC, implementation timeline, VNC model of one bridge mill and troubleshoot existing software and hardware problems with EN4NET. The final step of this virtual manufacturing project will be to integrate other production sites into the databases bringing JSC's EM3 into a position of becoming a clearing house for NASA's digital manufacturing needs creating a true virtual manufacturing enterprise.

Tony Rollins fashions a new tile for the Space Shuttle orbiter

NASA Technical Reports Server (NTRS)

1998-01-01

In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, holds down a curtain while making a test sample of tile on a block 5-axis computerized numerical control milling machine. About 70 percent of a Space Shuttle orbiter's external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. They are known as High-Temperature Reusable Surface Insulation (HRSI) tiles and Low-Temperature Reusable Surface Insulation (LRSI) tiles. Most HRSI tiles are 6 inches square, but may be as large as 12 inches in some areas, and 1 to 5 inches thick. LRSI tiles are generally 8 inches square, ranging from 0.2- to 1-inch thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter.

Making Complex Electrically Conductive Patterns on Cloth

NASA Technical Reports Server (NTRS)

Chu, Andrew; Fink, Patrick W.; Dobbins, Justin A.; Lin, Greg Y.; Scully, Robert C.; Trevino, Robert

2008-01-01

A method for automated fabrication of flexible, electrically conductive patterns on cloth substrates has been demonstrated. Products developed using this method, or related prior methods, are instances of a technology known as 'e-textiles,' in which electrically conductive patterns ar formed in, and on, textiles. For many applications, including high-speed digital circuits, antennas, and radio frequency (RF) circuits, an e-textile method should be capable of providing high surface conductivity, tight tolerances for control of characteristic impedances, and geometrically complex conductive patterns. Unlike prior methods, the present method satisfies all three of these criteria. Typical patterns can include such circuit structures as RF transmission lines, antennas, filters, and other conductive patterns equivalent to those of conventional printed circuits. The present method overcomes the limitations of the prior methods for forming the equivalent of printed circuits on cloth. A typical fabrication process according to the present method involves selecting the appropriate conductive and non-conductive fabric layers to build the e-textile circuit. The present method uses commercially available woven conductive cloth with established surface conductivity specifications. Dielectric constant, loss tangent, and thickness are some of the parameters to be considered for the non-conductive fabric layers. The circuit design of the conductive woven fabric is secured onto a non-conductive fabric layer using sewing, embroidery, and/or adhesive means. The portion of the conductive fabric that is not part of the circuit is next cut from the desired circuit using an automated machine such as a printed-circuit-board milling machine or a laser cutting machine. Fiducials can be used to align the circuit and the cutting machine. Multilayer circuits can be built starting with the inner layer and using conductive thread to make electrical connections between layers.

Fracture behavior of metal-ceramic fixed dental prostheses with frameworks from cast or a newly developed sintered cobalt-chromium alloy.

PubMed

Krug, Klaus-Peter; Knauber, Andreas W; Nothdurft, Frank P

2015-03-01

The aim of this study was to investigate the fracture behavior of metal-ceramic bridges with frameworks from cobalt-chromium-molybdenum (CoCrMo), which are manufactured using conventional casting or a new computer-aided design/computer-aided manufacturing (CAD/CAM) milling and sintering technique. A total of 32 metal-ceramic fixed dental prostheses (FDPs), which are based on a nonprecious metal framework, was produced using a conventional casting process (n = 16) or a new CAD/CAM milling and sintering process (n = 16). Eight unveneered frameworks were manufactured using each of the techniques. After thermal and mechanical aging of half of the restorations, all samples were subjected to a static loading test in a universal testing machine, in which acoustic emission monitoring was performed. Three different critical forces were revealed: the fracture force (F max), the force at the first reduction in force (F decr1), and the force at the critical acoustic event (F acoust1). With the exception of the veneered restorations with cast or sintered metal frameworks without artificial aging, which presented a statistically significant but slightly different F max, no statistically significant differences between cast and CAD/CAM sintered and milled FDPs were detected. Thermal and mechanical loading did not significantly affect the resulting forces. Cast and CAD/CAM milled and sintered metal-ceramic bridges were determined to be comparable with respect to the fracture behavior. FDPs based on CAD/CAM milled and sintered frameworks may be an applicable and less technique-sensitive alternative to frameworks that are based on conventionally cast frameworks.

A Low Noise, Microprocessor-Controlled, Internally Digitizing Rotating-Vane Electric Field Mill for Airborne Platforms

NASA Technical Reports Server (NTRS)

Bateman, M. G.; Stewart, M. F.; Blakeslee, R. J.; Podgorny, s. J.; Christian, H. J.; Mach, D. M.; Bailey, J. C.; Daskar, D.

2006-01-01

This paper reports on a new generation of aircraft-based rotating-vane style electric field mills designed and built at NASA's Marshall Spaceflight Center. The mills have individual microprocessors that digitize the electric field signal at the mill and respond to commands from the data system computer. The mills are very sensitive (1 V/m per bit), have a wide dynamic range (115 dB), and are very low noise (+/-1 LSB). Mounted on an aircraft, these mills can measure fields from +/-1 V/m to +/-500 kV/m. Once-per-second commanding from the data collection computer to each mill allows for precise timing and synchronization. The mills can also be commanded to execute a self-calibration in flight, which is done periodically to monitor the status and health of each mill.

High productivity machining of holes in Inconel 718 with SiAlON tools

NASA Astrophysics Data System (ADS)

Agirreurreta, Aitor Arruti; Pelegay, Jose Angel; Arrazola, Pedro Jose; Ørskov, Klaus Bonde

2016-10-01

Inconel 718 is often employed in aerospace engines and power generation turbines. Numerous researches have proven the enhanced productivity when turning with ceramic tools compared to carbide ones, however there is considerably less information with regard to milling. Moreover, no knowledge has been published about machining holes with this type of tools. Additional research on different machining techniques, like for instance circular ramping, is critical to expand the productivity improvements that ceramics can offer. In this a 3D model of the machining and a number of experiments with SiAlON round inserts have been carried out in order to evaluate the effect of the cutting speed and pitch on the tool wear and chip generation. The results of this analysis show that three different types of chips are generated and also that there are three potential wear zones. Top slice wear is identified as the most critical wear type followed by the notch wear as a secondary wear mechanism. Flank wear and adhesion are also found in most of the tests.

Atomistic simulations of focused ion beam machining of strained silicon

NASA Astrophysics Data System (ADS)

Guénolé, J.; Prakash, A.; Bitzek, E.

2017-09-01

The focused ion beam (FIB) technique has established itself as an indispensable tool in the material science community, both to analyze samples and to prepare specimens by FIB milling. In combination with digital image correlation (DIC), FIB milling can, furthermore, be used to evaluate intrinsic stresses by monitoring the strain release during milling. The irradiation damage introduced by such milling, however, results in a change in the stress/strain state and elastic properties of the material; changes in the strain state in turn affect the bonding strength, and are hence expected to implicitly influence irradiation damage formation and sputtering. To elucidate this complex interplay between strain, irradiation damage and sputtering, we perform TRIM calculations and molecular dynamics simulations on silicon irradiated by Ga+ ions, with slab and trench-like geometries, whilst simultaneously applying uniaxial tensile and compressive strains up to 4%. In addition we calculate the threshold displacement energy (TDE) and the surface binding energy (SBE) for various strain states. The sputter rate and amount of damage produced in the MD simulations show a clear influence of the strain state. The SBE shows no significant dependence on strain, but is strongly affected by surface reconstructions. The TDE shows a clear strain-dependence, which, however, cannot explain the influence of strain on the extent of the induced irradiation damage or the sputter rate.

Numerical simulation study on rolling-chemical milling process of aluminum-lithium alloy skin panel

NASA Astrophysics Data System (ADS)

Huang, Z. B.; Sun, Z. G.; Sun, X. F.; Li, X. Q.

2017-09-01

Single curvature parts such as aircraft fuselage skin panels are usually manufactured by rolling-chemical milling process, which is usually faced with the problem of geometric accuracy caused by springback. In most cases, the methods of manual adjustment and multiple roll bending are used to control or eliminate the springback. However, these methods can cause the increase of product cost and cycle, and lead to material performance degradation. Therefore, it is of significance to precisely control the springback of rolling-chemical milling process. In this paper, using the method of experiment and numerical simulation on rolling-chemical milling process, the simulation model for rolling-chemical milling process of 2060-T8 aluminum-lithium alloy skin was established and testified by the comparison between numerical simulation and experiment results for the validity. Then, based on the numerical simulation model, the relative technological parameters which influence on the curvature of the skin panel were analyzed. Finally, the prediction of springback and the compensation can be realized by controlling the process parameters.

Dynamic Testing of Signal Transduction Deregulation During Breast Cancer Initiation

DTIC Science & Technology

2011-07-01

1 at a chamber pressure of ~3 × 10-6 Torr for the electron beam evaporated films. A Hitachi FB2100 Focused Ion Beam milling machine with a gallium ...immobilization. These include physical absorption, layer-by-layer (LBL) assembly, and covalent attachment, and eventually chose the covalent attachment...testing real-time signaling in live breast cancer cells, it is important to evaluate the nanosensors to monitor fluorescent compounds in single

Research on tool wearing on milling of TC21 titanium alloy

NASA Astrophysics Data System (ADS)

Guilin, Liu

2017-06-01

Titanium alloys are used in aircraft widely, but the efficiency is a problem for machining titanium alloy. In this paper, the cutting experiment of TC21 titanium alloy was studied. Cutting parameters and test methods for TC21 titanium alloy were designed. The wear behavior of TC21 titanium alloy was studied based on analysis of orthogonal test results. It provides a group of cutting parameters for TC21 titanium alloy processing.

Theory, Design, and Measurement of Novel Uniform Circular Antenna Arrays for Direction of Arrival Estimation

DTIC Science & Technology

2015-01-01

generously offering the use of the printed circuit board (PCB) milling machine at the Royal Military College of Canada (RMC) as well as other lab... military research for over a century. However, continual technological advances in wireless communications along with widespread proliferation of...several decades, motivated initially by military applications. Over the past 10–15 years however, this topic has received widespread interest due in

45. VIEW OF UPPER LEVEL CRUSHER ADDITION FROM CRUSHED OXIDIZED ...

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

45. VIEW OF UPPER LEVEL CRUSHER ADDITION FROM CRUSHED OXIDIZED ORE BIN. 18 INCH BELT CONVEYOR BIN FEED, LOWER CENTER, WITH STEPHENS-ADAMSON 25 TON/HR ELEVATOR SPLIT DISCHARGE (OXIDIZED/UNOXIDIZED) IN CENTER. CRUDE ORE BINS AND MACHINE SHOP BEYOND. NOTE TOP OF CRUSHED OXIDIZED ORE BIN IS BELOW TOP OF CRUDE ORE BINS. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Reclamation of Wood Materials Coated with Lead-Based Paint

DTIC Science & Technology

2009-03-01

Also, the contractor’s deconstruction process required more labor than expected, raising the total project cost. Finally, the scale of the project did...paint1 (LBP) makes the removal and disposal of de- bris from these buildings problematic in terms of both process and cost. “Smash-n-trash...the wood that it covered. Proprietary milling machines and processes can be used to economically reclaim the lead- contaminated wood, providing a

75 FR 55274 - Change of Address for Region 5 State and Local Agencies; Technical Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-10

... Health District, Air Pollution Control, 33 Mill Street, Painesville, OH 44077. (xiv) Mahoning and...; Director, Canton City Health Department, Air Pollution Control Division, 420 Market Avenue North, Canton.... (xiii) Geauga and Lake Counties; Lake County General Health District, Air Pollution Control, 33 Mill...

Effect of formation temperature on properties of graphite/stannum composite for bipolar plate

NASA Astrophysics Data System (ADS)

Selamat, Mohd Zulkefli; Yusuf, Muhammad Yusri Md; Wer, Tio Kok; Sahadan, Siti Norbaya; Malingam, Sivakumar Dhar; Mohamad, Noraiham

2016-03-01

Bipolar plates are key components in Proton Exchange Membrane (PEM) fuel cells. They carry current away from the cell and withstand the clamping force of the stack assembly. Therefore, PEM fuel cell bipolar plates must have high electrical conductivity and adequate mechanical strength, in addition to being light weight and low cost in terms of both applicable materials and production methods. In this research, the raw materials used to fabricate the high performance bipolar plate are Graphite (Gr), Stannum (Sn) and Polypropylene (PP). All materials used was in powder form and Gr and Sn act as fillers and the PP acts as binder. The ratio of fillers (Gr/Sn) and binder (PP) was fixed at 80:20. For the multi-conductive filler, small amount of Sn, which is 10 up to 20wt% (from the total weight of fillers 80%) have been added into Gr/Sn/PP composite. The fillers were mixed by using the ball mill machine. The second stage of mixing process between the mixer of fillers and binder is also carried out by using ball mill machine before the compaction process by the hot press machine. The effect of formation temperatures (160°C-170°C) on the properties of Gr/Sn/PP composite had been studied in detail, especially the electrical conductivity, bulk density, hardness and microstructure analysis of Gr/Sn/PP composite. The result shows that there are significant improvement in the electrical conductivity and bulk density, which are exceeding the US-DoE target with the maximum value of 265.35 S/cm and 1.682g/cm3 respectively.

10 CFR 150.15a - Continued Commission authority pertaining to byproduct material.

Code of Federal Regulations, 2010 CFR

2010-01-01

... consistent with the provisions of the Uranium Mill Tailings Radiation Control Act of 1978, provided that the... Mill Tailings Radiation Control Act of 1978; and (6) The authority to enter into arrangements as may be...

Prevalence of respiratory symptoms and disorders among rice mill workers in India.

PubMed

Ghosh, Tirthankar; Gangopadhyay, Somnath; Das, Banibrata

2014-05-01

Lung function tests have become an integral part of assessment of pulmonary disease. Diseases of the respiratory system induced by occupational dusts are influenced by the duration of exposure. The aim of the study is to investigate the impairment of lung function and prevalence of respiratory symptoms among the rice mill workers. A total of 120 rice mill workers from three districts of Karnataka were included in this study. Fifty urban dwellers from the same socio-economic level were selected as controls. The study included clinical examination, assessment of respiratory symptoms, pulmonary function test, measurement of peak expiratory flow rate, absolute eosinophil count, ESR estimation, total IgE estimation and radiographic test. The present study has shown that the rice mill workers complained of several types of respiratory disorders like phlegm (40.8 %), dyspnea (44.2 %), chest tightness (26.7 %), cough (21.7 %), and nose irritation (27.5 %). Rice mill workers exposed to dust presented significantly (p < 0.05) lower levels of FVC (3.44 ± 0.11), FEV1 (2.73 ± 0.15) and PEFR (304.95 ± 28.79) than the controls. The rice mill workers are having significantly higher absolute eosinophil counts, total IgE and ESR than control groups. The hematological findings suggest that the harmful effects may be linked to both non-specific irritation and allergic responses to rice husk dust among rice mill workers. Dust exposure in the working environment affects the lung function values and increased the respiratory symptoms among the rice mill workers.

40 CFR 192.00 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-07-01

... AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the Control of Residual Radioactive Materials from Inactive Uranium Processing Sites § 192.00 Applicability. This... sites under section 108 of the Uranium Mill Tailings Radiation Control Act of 1978 (henceforth...

40 CFR 192.00 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the Control of Residual Radioactive Materials from Inactive Uranium Processing Sites § 192.00 Applicability. This... sites under section 108 of the Uranium Mill Tailings Radiation Control Act of 1978 (henceforth...

40 CFR 192.00 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-07-01

... AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the Control of Residual Radioactive Materials from Inactive Uranium Processing Sites § 192.00 Applicability. This... sites under section 108 of the Uranium Mill Tailings Radiation Control Act of 1978 (henceforth...

40 CFR 192.00 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

... AND ENVIRONMENTAL PROTECTION STANDARDS FOR URANIUM AND THORIUM MILL TAILINGS Standards for the Control of Residual Radioactive Materials from Inactive Uranium Processing Sites § 192.00 Applicability. This... sites under section 108 of the Uranium Mill Tailings Radiation Control Act of 1978 (henceforth...

Crystallization of high-strength nano-scale leucite glass-ceramics.

PubMed

Theocharopoulos, A; Chen, X; Wilson, R M; Hill, R; Cattell, M J

2013-11-01

Fine-grained, high strength, translucent leucite dental glass-ceramics are synthesized via controlled crystallization of finely milled glass powders. The objectives of this study were to utilize high speed planetary milling of an aluminosilicate glass for controlled surface crystallization of nano-scale leucite glass-ceramics and to test the biaxial flexural strength. An aluminosilicate glass was synthesized, attritor or planetary milled and heat-treated. Glasses and glass-ceramics were characterized using particle size analysis, X-ray diffraction and scanning electron microscopy. Experimental (fine and nanoscale) and commercial (Ceramco-3, IPS Empress Esthetic) leucite glass-ceramics were tested using the biaxial flexural strength (BFS) test. Gaussian and Weibull statistics were applied. Experimental planetary milled glass-ceramics showed an increased leucite crystal number and nano-scale median crystal sizes (0.048-0.055 μm(2)) as a result of glass particle size reduction and heat treatments. Experimental materials had significantly (p<0.05) higher mean BFS and characteristic strength values than the commercial materials. Attritor milled and planetary milled (2h) materials showed no significant (p>0.05) strength difference. All other groups' mean BFS and characteristic strengths were found to be significantly different (p<0.05) to each other. The mean (SD) MPa strengths measured were: Attritor milled: 252.4 (38.7), Planetary milled: 225.4 (41.8) [4h milling] 255.0 (35.0) [2h milling], Ceramco-3: 75.7 (6.8) and IPS Empress: 165.5 (30.6). Planetary milling enabled synthesis of nano-scale leucite glass-ceramics with high flexural strength. These materials may help to reduce problems associated with brittle fracture of all-ceramic restorations and give reduced enamel wear. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

John Stuart Mill on Freedom, Education, and Social Reform.

ERIC Educational Resources Information Center

Carbone, Peter F.

1983-01-01

Examines the social philosophy of John Stuart Mill, emphasizing his views on freedom, education, and social reform. Considers Mill's individualism and reformism, the conflict between freedom and control that characterizes his work, and the importance of freedom and education. Suggests caution in drawing educational implications from his work. (DAB)

Effect of cutting parameters on strain hardening of nickel–titanium shape memory alloy

NASA Astrophysics Data System (ADS)

Wang, Guijie; Liu, Zhanqiang; Ai, Xing; Huang, Weimin; Niu, Jintao

2018-07-01

Nickel–titanium shape memory alloy (SMA) has been widely used as implant materials due to its good biocompatibility, shape memory property and super-elasticity. However, the severe strain hardening is a main challenge due to cutting force and temperature caused by machining. An orthogonal experiment of nickel–titanium SMA with different milling parameters conditions was conducted in this paper. On the one hand, the effect of cutting parameters on work hardening is obtained. It is found that the cutting speed has the most important effect on work hardening. The depth of machining induced layer and the degree of hardening become smaller with the increase of cutting speed when the cutting speed is less than 200 m min‑1 and then get larger with further increase of cutting speed. The relative intensity of diffraction peak increases as the cutting speed increase. In addition, all of the depth of machining induced layer, the degree of hardening and the relative intensity of diffraction peak increase when the feed rate increases. On the other hand, it is found that the depth of machining induced layer is closely related with the degree of hardening and phase transition. The higher the content of austenite in the machined surface is, the higher the degree of hardening will be. The depth of the machining induced layer increases with the degree of hardening increasing.

Acquisition of thin coronal sectional dataset of cadaveric liver.

PubMed

Lou, Li; Liu, Shu Wei; Zhao, Zhen Mei; Tang, Yu Chun; Lin, Xiang Tao

2014-04-01

To obtain the thin coronal sectional anatomic dataset of the liver by using digital freezing milling technique. The upper abdomen of one Chinese adult cadaver was selected as the specimen. After CT and MRI examinations verification of absent liver lesions, the specimen was embedded with gelatin in stand erect position and frozen under profound hypothermia, and the specimen was then serially sectioned from anterior to posterior layer by layer with digital milling machine in the freezing chamber. The sequential images were captured by means of a digital camera and the dataset was imported to imaging workstation. The thin serial section of the liver added up to 699 layers with each layer being 0.2 mm in thickness. The shape, location, structure, intrahepatic vessels and adjacent structures of the liver was displayed clearly on each layer of the coronal sectional slice. CT and MR images through the body were obtained at 1.0 and 3.0 mm intervals, respectively. The methodology reported here is an adaptation of the milling methods previously described, which is a new data acquisition method for sectional anatomy. The thin coronal sectional anatomic dataset of the liver obtained by this technique is of high precision and good quality.

Performance Improvement of Friction Stir Welds by Better Surface Finish

NASA Technical Reports Server (NTRS)

Russell, Sam; Nettles, Mindy

2015-01-01

The as-welded friction stir weld has a cross section that may act as a stress concentrator. The geometry associated with the stress concentration may reduce the weld strength and it makes the weld challenging to inspect with ultrasound. In some cases, the geometry leads to false positive nondestructive evaluation (NDE) indications and, in many cases, it requires manual blending to facilitate the inspection. This study will measure the stress concentration effect and develop an improved phased array ultrasound testing (PAUT) technique for friction stir welding. Post-welding, the friction stir weld (FSW) tool would be fitted with an end mill that would machine the weld smooth, trimmed shaved. This would eliminate the need for manual weld preparation for ultrasonic inspections. Manual surface preparation is a hand operation that varies widely depending on the person preparing the welds. Shaving is a process that can be automated and tightly controlled.

Three-dimensional machining of carbon nanotube forests using water-assisted scanning electron microscope processing

NASA Astrophysics Data System (ADS)

Rajabifar, Bahram; Kim, Sanha; Slinker, Keith; Ehlert, Gregory J.; Hart, A. John; Maschmann, Matthew R.

2015-10-01

We demonstrate that vertically aligned carbon nanotubes (CNTs) can be precisely machined in a low pressure water vapor ambient using the electron beam of an environmental scanning electron microscope. The electron beam locally damages the irradiated regions of the CNT forest and also dissociates the water vapor molecules into reactive species including hydroxyl radicals. These species then locally oxidize the damaged region of the CNTs. The technique offers material removal capabilities ranging from selected CNTs to hundreds of cubic microns. We study how the material removal rate is influenced by the acceleration voltage, beam current, dwell time, operating pressure, and CNT orientation. Milled cuts with depths between 0-100 microns are generated, corresponding to a material removal rate of up to 20.1 μm3/min. The technique produces little carbon residue and does not disturb the native morphology of the CNT network. Finally, we demonstrate direct machining of pyramidal surfaces and re-entrant cuts to create freestanding geometries.

Three-dimensional machining of carbon nanotube forests using water-assisted scanning electron microscope processing

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

Rajabifar, Bahram; Maschmann, Matthew R., E-mail: MaschmannM@missouri.edu; Kim, Sanha

2015-10-05

We demonstrate that vertically aligned carbon nanotubes (CNTs) can be precisely machined in a low pressure water vapor ambient using the electron beam of an environmental scanning electron microscope. The electron beam locally damages the irradiated regions of the CNT forest and also dissociates the water vapor molecules into reactive species including hydroxyl radicals. These species then locally oxidize the damaged region of the CNTs. The technique offers material removal capabilities ranging from selected CNTs to hundreds of cubic microns. We study how the material removal rate is influenced by the acceleration voltage, beam current, dwell time, operating pressure, andmore » CNT orientation. Milled cuts with depths between 0–100 microns are generated, corresponding to a material removal rate of up to 20.1 μm{sup 3}/min. The technique produces little carbon residue and does not disturb the native morphology of the CNT network. Finally, we demonstrate direct machining of pyramidal surfaces and re-entrant cuts to create freestanding geometries.« less

Ultra-precision turning of complex spiral optical delay line

NASA Astrophysics Data System (ADS)

Zhang, Xiaodong; Li, Po; Fang, Fengzhou; Wang, Qichang

2011-11-01

Optical delay line (ODL) implements the vertical or depth scanning of optical coherence tomography, which is the most important factor affecting the scanning resolution and speed. The spinning spiral mirror is found as an excellent optical delay device because of the high-speed and high-repetition-rate. However, it is one difficult task to machine the mirror due to the special shape and precision requirement. In this paper, the spiral mirror with titled parabolic generatrix is proposed, and the ultra-precision turning method is studied for its machining using the spiral mathematic model. Another type of ODL with the segmental shape is also introduced and machined to make rotation balance for the mass equalization when scanning. The efficiency improvement is considered in details, including the rough cutting with the 5- axis milling machine, the machining coordinates unification, and the selection of layer direction in turning. The onmachine measuring method based on stylus gauge is designed to analyze the shape deviation. The air bearing is used as the measuring staff and the laser interferometer sensor as the position sensor, whose repeatability accuracy is proved up to 10nm and the stable feature keeps well. With this method developed, the complex mirror with nanometric finish of 10.7nm in Ra and the form error within 1um are achieved.

A Comparison of the Marginal and Internal Fit of Cobalt- Chromium Copings Fabricated by Two Different CAD/CAM Systems (CAD/ Milling, CAD/ Ceramill Sintron).

PubMed

Vojdani, Mahroo; Torabi, Kianoosh; Atashkar, Berivan; Heidari, Hossein; Torabi Ardakani, Mahshid

2016-12-01

Marginal fitness is the most important criteria for evaluation of the clinical acceptability of a cast restoration. Marginal gap which is due to cement solubility and plaque retention is potentially detrimental to both tooth and periodontal tissues. This in vitro study aimed to evaluate the marginal and internal fit of cobalt- chromium (Co-Cr) copings fabricated by two different CAD/CAM systems: (CAD/ milling and CAD/ Ceramill Sintron). We prepared one machined standard stainless steel master model with following dimensions: 7 mm height, 5mm diameter, 90˚ shoulder marginal finish line with 1 mm width, 10˚ convergence angle and anti-rotational surface on the buccal aspect of the die. There were 10 copings produced from hard presintered Co-Cr blocks according to CAD/ Milling technique and ten copings from soft non- presintered Co-Cr blocks according to CAD/ Ceramill Sintron technique. Marginal and internal accuracies of copings were documented by the replica technique. Replicas were examined at ten reference points under a digital microscope (230X). The Student's t-test was used for statistical analysis. p < 0.001 was considered significant. Statistically significant differences existed between the groups ( p < 0.001). The CAD/milling group (hard copings) had a mean marginal discrepancy (MD) of 104 µm, axial discrepancy (AD) of 23 µm and occlusal discrepancy of 130 µm. For CAD/ Ceramill Sintron group, these values were 195 µm (MD), 46 µm (AD), and 232 µm (OD). Internal total discrepancy (ITD) for the CAD/milling group was 77 µm, whereas for the CAD/Ceramill Sintron group was 143 µm. Hard presintered Co-Cr copings had significantly higher marginal and internal accuracies compared to the soft non-presintered copings.

Decoupling the Arrhenius equation via mechanochemistry.

PubMed

Andersen, Joel M; Mack, James

2017-08-01

Mechanochemistry continues to reveal new possibilities in chemistry including the opportunity for "greening" reactions. Nevertheless, a clear understanding of the energetic transformations within mechanochemical systems remains elusive. We employed a uniquely modified ball mill and strategically chosen Diels-Alder reactions to evaluate the role of several ball-milling variables. This revealed three different energetic regions that we believe are defining characteristics of most, if not all, mechanochemical reactors. Relative to the locations of a given ball mill's regions, activation energy determines whether a reaction is energetically easy (Region I), challenging (Region II), or unreasonable (Region III) in a given timeframe. It is in Region II, that great sensitivity to mechanochemical conditions such as vial material and oscillation frequency emerge. Our unique modifications granted control of reaction vessel temperature, which in turn allowed control of the locations of Regions I, II, and III for our mill. Taken together, these results suggest envisioning vibratory mills (and likely other mechanochemical methodologies) as molecular-collision facilitating devices that act upon molecules occupying a thermally-derived energy distribution. This unifies ball-milling energetics with solution-reaction energetics via a common tie to the Arrhenius equation, but gives mechanochemistry the unique opportunity to influence either half of the equation. In light of this, we discuss a strategy for translating solvent-based reaction conditions to ball milling conditions. Lastly, we posit that the extra control via frequency factor grants mechanochemistry the potential for greater selectivity than conventional solution reactions.

Orion Heat Shield Testing

NASA Image and Video Library

2015-05-26

THE ORION HEAT SHIELD, WHICH WAS AT NASA’S MARSHALL SPACE FLIGHT CENTER FROM MARCH-MAY 2015 FOR ENGINEERING AND ANALYSIS, IS READIED FOR DEPARTURE AT THE END OF ITS STAY. THE HEAT SHIELD’S ABLATED SURFACE MATERIAL WAS REMOVED AT MARSHALL FOR ANALYSIS, USING THE CENTER’S STATE-OF-THE-ART SEVEN-AXIS MILLING MACHINE. IT NEXT WILL GO TO NASA’S LANGLEY RESEARCH CENTER FOR WATER-IMPACT TESTING. NASA’S JOHNSON SPACE CENTER LEADS THE ORION PROGRAM FOR NASA.

Orion Heat Shield Testing

NASA Image and Video Library

2015-05-28

THE ORION HEAT SHIELD, WHICH WAS AT NASA’S MARSHALL SPACE FLIGHT CENTER FROM MARCH-MAY 2015 FOR ENGINEERING AND ANALYSIS, IS READIED FOR DEPARTURE AT THE END OF ITS STAY. THE HEAT SHIELD’S ABLATED SURFACE MATERIAL WAS REMOVED AT MARSHALL FOR ANALYSIS, USING THE CENTER’S STATE-OF-THE-ART SEVEN-AXIS MILLING MACHINE. IT NEXT WILL GO TO NASA’S LANGLEY RESEARCH CENTER FOR WATER-IMPACT TESTING. NASA’S JOHNSON SPACE CENTER LEADS THE ORION PROGRAM FOR NASA.

Diamond fly cutting of aluminum thermal infrared flat mirrors for the OSIRIS-REx Thermal Emission Spectrometer (OTES) instrument

NASA Astrophysics Data System (ADS)

Groppi, Christopher E.; Underhill, Matthew; Farkas, Zoltan; Pelham, Daniel

2016-07-01

We present the fabrication and measurement of monolithic aluminum flat mirrors designed to operate in the thermal infrared for the OSIRIS-Rex Thermal Emission Spectrometer (OTES) space instrument. The mirrors were cut using a conventional fly cutter with a large radius diamond cutting tool on a high precision Kern Evo 3-axis CNC milling machine. The mirrors were measured to have less than 150 angstroms RMS surface error.

The Measurement of Residual Stresses by X-Ray Diffraction Techniques

DTIC Science & Technology

1978-09-26

Sutton, (1967)for an Al alloy , and in Volorinta, (1965)for a low carbon steel. In materials that undergo phase changes even more complex stre~s states may...extensive study of surface integrity in machining steels and Ti alloys , including the effects of induced phase transformations . It is interesting to rote...that phase transformations did 7 not occur in milling operations, and hence similar stress patterns were found in both alloys . Grinding has been examined

Strengthening of NiAl Matrix Composites

DTIC Science & Technology

1991-10-01

taille des sous-grains. Les donn&s obtenues pour une serie d’exp&iences indiquent que hit densitc de dislocations croit lorsque Ia fraction volumique de...electrical discharge 8. H. Fujita. T. Tabata , K. Yoshida. N. Summida and S. Katagiri, Japan J. appl. Phys. II, 1522 (1972).machining, dimpling and ion...milling does not intro- 9. H. Fujita and T. Tabata , Japan J. appl. Phys. 12, 471 duce dislocations into the matrix. (1973). * In order to obtain realistic

Microstructure, Mechanical Properties, and Flatness of SEBM Ti-6Al-4V Sheet in As-Built and Hot Isostatically Pressed Conditions

NASA Astrophysics Data System (ADS)

Tang, H. P.; Wang, J.; Song, C. N.; Liu, N.; Jia, L.; Elambasseril, J.; Qian, M.

2017-03-01

Sheet (0.41-4.80 mm thick) or thin plate structures commonly exist in additively manufactured Ti-6Al-4V components for load-bearing applications. A batch of 64 Ti-6Al-4V sheet samples with dimensions of 210/180 mm × 42 mm × 3 mm have been additively manufactured by selective electron beam melting (SEBM). A comprehensive assessment was then made of their density, surface flatness, microstructure, and mechanical properties in both as-built and hot isostatically pressed conditions, including the influence of the hot isostatic pressing (HIP) temperature. In particular, standard long tensile (156 mm long, 2 mm thick) and fatigue (206 mm long, 2 mm thick) test sheet samples were used for assessment. As-built SEBM Ti-6Al-4V sheet samples with machined surfaces fully satisfied the minimum tensile property requirements for mill-annealed TIMETAL Ti-6Al-4V sheet products, whereas HIP-processed samples (2 mm thick) with machined surfaces achieved a high cycle fatigue (HCF) strength of 625 MPa (R = 0.06, 107 cycles), similar to mill-annealed Ti-6Al-4V (500-700 MPa). The unflatness was limited to 0.2 mm in both the as-built and HIP-processed conditions. A range of other revealing observations was discussed for the additive manufacturing of the Ti-6Al-4V sheet structures.

Ion-plasma gun for ion-milling machine

DOEpatents

Kaminsky, Manfred S.; Campana, Jr., Thomas J.

1976-01-01

An ion gun includes an elongated electrode with a hollow end portion closed by a perforated end plate. The end plate is positioned parallel to a perforated flat electrode of opposite electrical polarity. An insulated sleeve encompasses the elongated electrode and extends outwardly from the perforated end towards the flat electrode. The sleeve length is separated into two portions of different materials. The first is formed of a high-temperature material that extends over the hollow portion of the elongated electrode where the arc is initiated by a point source electrode. The second sleeve portion extending over the remainder of the elongated electrode is of a resilient material for enhanced seal-forming ability and retention of plasma gas. Perforations are arranged in the flat electrode in a mutually opposing triangular pattern to project a plasma beam having a generally flat current profile towards a target requiring precision milling.

Investigation of 1-Dimensional ultrasonic vibration compliance mechanism based on finite element analysis

NASA Astrophysics Data System (ADS)

Latif, A. Afiff; Ibrahim, M. Rasidi; Rahim, E. A.; Cheng, K.

2017-04-01

The conventional milling has many difficulties in the processing of hard and brittle material. Hence, ultrasonic vibration assisted milling (UVAM) was proposed to overcome this problem. The objective of this research is to study the behavior of compliance mechanism (CM) as the critical part affect the performance of the UVAM. The design of the CM was investigated and focuses on 1-Dimensional. Experimental result was obtained from a portable laser digital vibrometer. While the 1-Dimensional value such as safety factor, deformation of hinges and stress analysis are obtained from finite elements simulation. Finally, the findings help to find the best design judging from the most travelled distance of the piezoelectric actuators. In addition, this paper would provide a clear picture the behavior of the CM embedded in the UVAM, which can provide good data and to improve the machining on reducing tool wear, and lower cutting force on the workpiece surface roughness.

Analysis of Surface and Subsurface Damage Morphology in Rotary Ultrasonic Machining of BK7 Glass

NASA Astrophysics Data System (ADS)

Hong-xiang, Wang; Chu, Wang; Jun-liang, Liu; Shi, Gao; Wen-Jie, Zhai

2017-11-01

This paper investigates the formation process of surface/subsurface damage in the rotary ultrasonic machining of BK7 glass. The results show that during the milling using the end face of the tool, the cutting depth and the residual height between the abrasive grains constantly change with the high-frequency vibration, generating lots of cracks on both sides of the scratches. The high-frequency vibration accelerates the chips falling from the surface, so that the chips and thermal damage are reduced, causing the grinding surface quality better. A plastic deformation area is formed during the grinding, due to the non-uniform cutting force on the material surface, and the residual stress is produced in the deformation area, inducing the median/lateral cracks.

78 FR 27402 - Agency Information Collection Activities; Submission for Office of Management and Budget Review...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-10

... Request; Medicated Feed Mill License Application; Extension AGENCY: Food and Drug Administration, HHS... review and clearance. Medicated Feed Mill Licensing Application--21 CFR Part 515 (OMB Control Number 0910... medicated feed with a general licensing system for feed mills. Before passage of the ADAA, medicated feed...

Bay Mills' Bold Approach

ERIC Educational Resources Information Center

Freedman, Eric

2011-01-01

It's a long, long way from Bay Mills Community College, near the shores of frigid Lake Superior, to Detroit. But distance, time and demographics aside, the school and the city are united by Bay Mills' status as the nation's only tribally controlled college that authorizes quasi-public schools, known officially as public school academies. And it's…

The synergistic effects of combining the high energy mechanical milling and wet milling on Si negative electrode materials for lithium ion battery

NASA Astrophysics Data System (ADS)

Hou, Shang-Chieh; Su, Yuh-Fan; Chang, Chia-Chin; Hu, Chih-Wei; Chen, Tsan-Yao; Yang, Shun-Min; Huang, Jow-Lay

2017-05-01

The submicro-sized and nanostructured Si aggregated powder is prepared by combinational routes of high energy mechanical milling (HEMM) and wet milling. Milled Si powder is investigated by particle size analyzer, SEM, TEM, XPS and XRD as well as the control ones. Its electrode is also investigated by in situ XRD and electrochemical performance. Morphology reveals that combining the high energy mechanical milling and wet milling not only fracture primary Si particles but also form submicro-sized Si aggregates constructed by amorphous and nanocrystalline phases. Moreover, XPS shows that wet milling in ethanol trigger Sisbnd Osbnd CH2CH3 bonding on Si surface might enhance the SEI formation. In situ XRD analysis shows negative electrode made of submicro-sized Si aggregated powder can effectively suppress formation of crystalline Li15Si4 during lithiation and delithiation due to amorphous and nanocrystalline construction. Thus, the submicro-sized Si powder with synergistic effects combining the high energy mechanical milling and wet milling in ethanol as negative electrode performs better capacity retention.

Identification of milling and baking quality QTL in multiple soft wheat mapping populations

USDA-ARS?s Scientific Manuscript database

Wheat derived food products require a range of characteristics. Identification and understanding of the genetic components controlling end-use quality of wheat is important for crop improvement. We assessed the underlying genetics controlling specific milling and baking quality parameters of soft wh...

A comparison between customized clear and removable orthodontic appliances manufactured using RP and CNC techniques.

PubMed

Martorelli, Massimo; Gerbino, Salvatore; Giudice, Michele; Ausiello, Pietro

2013-02-01

Aim of the research is to compare the orthodontic appliances fabricated by using rapid prototyping (RP) systems, in particular 3D printers, with those manufactured by using computer numerical control (CNC) milling machines. 3D printing is today a well-accepted technology to fabricate orthodontic aligners by using the thermoforming process, instead the potential of CNC systems in dentistry have not yet been sufficiently explored. One patient, with mal-positioned maxillary central and lateral incisors, was initially selected. In the computer aided virtual planning was defined that, for the treatment, the patient needed to wear a series of 7 removable orthodontic appliances (ROA) over a duration of 21 weeks, with one appliance for every 3 weeks. A non-contact reverse engineering (RE) structured-light 3D scanner was used to create the 3D STL model of the impression of the patient's mouth. Numerical FEM simulations were performed varying the position of applied forces (discrete and continuous forces) on the same model, simulating, in this way, 3 models with slice thickness of 0.2 mm, 0.1 mm (RP staircase effect) and without slicing (ideal case). To define the areas of application of forces, two configuration "i" and "i-1" of the treatment were overlapped. 6 patients to which for three steps (3rd, 4th and 5th step) were made to wear aligners fabricated starting from physical models by 3D printing (3DP-ROA) and afterwards, for the next steps (6th, 7th and 8th step), aligners fabricated starting from physical models by CNC milling machine (CNC-ROA), were selected. For the 6 patients wearing the CNC-ROA, it was observed a best fitting of the aligner to the teeth and a more rapid teeth movement than the 3DP-ROA (2 weeks compared to 3 weeks for every appliance). FEM simulations showed a more uniform stress distribution for CNC-ROA than 3DP-ROA. In this research, 6 different case studies and CAD-FEM simulations showed that, to fabricate an efficient clear and removable orthodontic aligner, it is necessary to consider a compromise of several factors. A lower staircase effect (lower layer thickness) and a higher physical prototype accuracy allow a better control of tooth movement. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

DOE/NETL's phase II mercury control technology field testing program: preliminary economic analysis of activated carbon injection.

PubMed

Jones, Andrew P; Hoffmann, Jeffrey W; Smith, Dennis N; Feeley, Thomas J; Murphy, James T

2007-02-15

Based on results of field testing conducted by the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL), this article provides preliminary costs for mercury control via conventional activated carbon injection (ACI), brominated ACI, and conventional ACI coupled with the application of a sorbent enhancement additive (SEA) to coal prior to combustion. The economic analyses are reported on a plant-specific basis in terms of the cost required to achieve low (50%), mid (70%), and high (90%) levels of mercury removal "above and beyond" the baseline mercury removal achieved by existing emission control equipment. In other words, the levels of mercury control are directly attributable to ACI. Mercury control costs via ACI have been amortized on a current dollar basis. Using a 20-year book life, levelized costs for the incremental increase in cost of electricity (COE), expressed in mills per kilowatt-hour (mills/kWh), and the incremental cost of mercury control, expressed in dollars per pound of mercury removed ($/lb Hg removed), have been calculated for each level of ACI mercury control. For this analysis, the increase in COE varied from 0.14 mills/kWh to 3.92 mills/kWh. Meanwhile, the incremental cost of mercury control ranged from $3810/lb Hg removed to $166000/lb Hg removed.

Impact of industrial effluents on the biochemical composition of fresh water fish Labeo rohita.

PubMed

Muley, D V; Karanjkar, D M; Maske, S V

2007-04-01

In acute toxicity (96 hr) experiment the fingerlings of freshwater fish Labeo rohita was exposed to tannery, electroplating and textile mill effluents. The LC0 and LC50 concentrations were 15% and 20% for tannery effluents, 3% and 6% for electroplating effluents and 18% and 22% for textile mill effluents respectively. It was found that, electroplating effluent was more toxic than tannery and textile mill wastes. After acute toxicity experiments for different industrial effluents, various tissues viz. gill, liver, muscle and kidney were obtained separately from control, LC0 and LC50 groups. These tissues were used for biochemical estimations. The glycogen content in all the tissues decreased considerably upon acute toxicity of three industrial effluents except muscle in LC50 group of tannery effluent and kidney in LC50 group of textile mill effluent, when compared to control group. The total protein content decreased in all tissues in three effluents except gills in LC50 group of tannery effluent, kidney in LC50 group of electroplating effluent and kidney in LC0 group of textile mill effluent. In general total lipid content decreased in all tissues after acute exposure when compared to control group. The results obtained in the present study showed that, the industrial effluents from tannery, electroplating and textile mills caused marked depletion in biochemical composition in various tissues of the fish Labeo rohita after acute exposure.

3D Graphics For Interactive Surgical Simulation And Implant Design

NASA Astrophysics Data System (ADS)

Dev, P.; Fellingham, L. L.; Vassiliadis, A.; Woolson, S. T.; White, D. N.; Young, S. L.

1984-10-01

The combination of user-friendly, highly interactive software, 3D graphics, and the high-resolution detailed views of anatomy afforded by X-ray computer tomography and magnetic resonance imaging can provide surgeons with the ability to plan and practice complex surgeries. In addition to providing a realistic and manipulable 3D graphics display, this system can drive a milling machine in order to produce physical models of the anatomy or prosthetic devices and implants which have been designed using its interactive graphics editing facilities.

Simulating The Technological Movements Of The Equipment Used For Manufacturing Prosthetic Devices Using 3D Models

NASA Astrophysics Data System (ADS)

Chicea, Anca-Lucia

2015-09-01

The paper presents the process of building geometric and kinematic models of a technological equipment used in the process of manufacturing devices. First, the process of building the model for a six axes industrial robot is presented. In the second part of the paper, the process of building the model for a five-axis CNC milling machining center is also shown. Both models can be used for accurate cutting processes simulation of complex parts, such as prosthetic devices.

A Study on Improvement of Machining Precision in a Medical Milling Robot

NASA Astrophysics Data System (ADS)

Sugita, Naohiko; Osa, Takayuki; Nakajima, Yoshikazu; Mori, Masahiko; Saraie, Hidenori; Mitsuishi, Mamoru

Minimal invasiveness and increasing of precision have recently become important issues in orthopedic surgery. The femur and tibia must be cut precisely for successful knee arthroplasty. The recent trend towards Minimally Invasive Surgery (MIS) has increased surgical difficulty since the incision length and open access area are small. In this paper, the result of deformation analysis of the robot and an active compensation method of robot deformation, which is based on an error map, are proposed and evaluated.

The Concept of Electrically Assisted Friction Stir Welding (EAFSW) and Application to the Processing of Various Metals

DTIC Science & Technology

2008-09-01

unavailability of a precise load cell. This scale was set on the machine working table. Since the shaft spindle had been placed in fixed vertical...4 Figure 4. Mill Spindle with Slip Ring and Brush Assembly, Weld Tip is in W orking Position...areas . FSW of HSLA 65 and Type 304L Processing Parameter HSLA-65 304L Spindle Speed (RPM) 850 850 Travel Speed (ipm) 6 2 Z-Load (Ibs) 3500 3500

Novel hydrophilic nanostructured microtexture on direct metal laser sintered Ti-6Al-4V surfaces enhances osteoblast response in vitro and osseointegration in a rabbit model.

PubMed

Hyzy, Sharon L; Cheng, Alice; Cohen, David J; Yatzkaier, Gustavo; Whitehead, Alexander J; Clohessy, Ryan M; Gittens, Rolando A; Boyan, Barbara D; Schwartz, Zvi

2016-08-01

The purpose of this study was to compare the biological effects in vivo of hierarchical surface roughness on laser sintered titanium-aluminum-vanadium (Ti-6Al-4V) implants to those of conventionally machined implants on osteoblast response in vitro and osseointegration. Laser sintered disks were fabricated to have micro-/nano-roughness and wettability. Control disks were computer numerical control (CNC) milled and then polished to be smooth (CNC-M). Laser sintered disks were polished smooth (LST-M), grit blasted (LST-B), or blasted and acid etched (LST-BE). LST-BE implants or implants manufactured by CNC milling and grit blasted (CNC-B) were implanted in the femurs of male New Zealand white rabbits. Most osteoblast differentiation markers and local factors were enhanced on rough LST-B and LST-BE surfaces in comparison to smooth CNC-M or LST-M surfaces for MG63 and normal human osteoblast cells. To determine if LST-BE implants were osteogenic in vivo, we compared them to implant surfaces used clinically. LST-BE implants had a unique surface with combined micro-/nano-roughness and higher wettability than conventional CNC-B implants. Histomorphometric analysis demonstrated a significant improvement in cortical bone-implant contact of LST-BE implants compared to CNC-B implants after 3 and 6 weeks. However, mechanical testing revealed no differences between implant pullout forces at those time points. LST surfaces enhanced osteoblast differentiation and production of local factors in vitro and improved the osseointegration process in vivo. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2086-2098, 2016. © 2016 Wiley Periodicals, Inc.

[Preliminary evaluation of clinical effect of computer aided design and computer aided manufacture zirconia crown].

PubMed

Wang, Yu-guang; Xing, Yan-xi; Sun, Yu-chun; Zhao, Yi-jiao; Lü, Pei-jun; Wang, Yong

2013-06-01

To evaluate clinical effects of computer aided design and computer aided manufacturing (CAD/CAM) milled zirconia crown in three aspects: aesthetic, contact wear and fracture. Sixty patients were divided into two groups.In one group, 35 full contour CAD/CAM zirconia crown were made on molars of 30 patients. The manufacturing process of zirconia crown was as follow. First, the three dimensional(3-D) data of working models, antagonist impression and check records were acquired by 3-D laser scanning Dental wings S50. Then full contour zirconia crowns, which had functional occlusal contacts with antagonistic teeth, and appropriate contact with adjacent teeth were designed with Zeno-CAD(V4.2.5.5.12919) software. ZENOSTAR Zr pure zirconia material was milled in digital controlled machine WIELAND 4030 M1.In the end, the zirconia crown were completed with the method of second sintering and polishing. After clinical try-in, the crown was cemented.In the control group, thirty gold alloy full crown were made and cemented on molars of 30 patients. According to the modified U S Public Health Service Criteria(USPHS) evaluation standard, all crowns were evaluated on the same day, at three months, half a year, one year and two years following delivery. There were three aspects we were focusing on in the evaluation: aesthetic, contact wear(restoration and antagonist), and fracture. In all the prosthesis we evaluated during the 24 months, no fracture was found. Contact wear of crowns varies according to different antagonist teeth. The zirconia crowns show privilege in aesthesis, toughness and anti-wearing.However, there is contact wear on antagonistic natural teeth. Thus it is a good choice when full zirconia crowns are indicated on two antagonistic teeth in both jaws.

Part height control of laser metal additive manufacturing process

NASA Astrophysics Data System (ADS)

Pan, Yu-Herng

Laser Metal Deposition (LMD) has been used to not only make but also repair damaged parts in a layer-by-layer fashion. Parts made in this manner may produce less waste than those made through conventional machining processes. However, a common issue of LMD involves controlling the deposition's layer thickness. Accuracy is important, and as it increases, both the time required to produce the part and the material wasted during the material removal process (e.g., milling, lathe) decrease. The deposition rate is affected by multiple parameters, such as the powder feed rate, laser input power, axis feed rate, material type, and part design, the values of each of which may change during the LMD process. Using a mathematical model to build a generic equation that predicts the deposition's layer thickness is difficult due to these complex parameters. In this thesis, we propose a simple method that utilizes a single device. This device uses a pyrometer to monitor the current build height, thereby allowing the layer thickness to be controlled during the LMD process. This method also helps the LMD system to build parts even with complex parameters and to increase material efficiency.

Application of high speed machining technology in aviation

NASA Astrophysics Data System (ADS)

Bałon, Paweł; Szostak, Janusz; Kiełbasa, Bartłomiej; Rejman, Edward; Smusz, Robert

2018-05-01

Aircraft structures are exposed to many loads during their working lifespan. Every particular action made during a flight is composed of a series of air movements which generate various aircraft loads. The most rigorous requirement which modern aircraft structures must fulfill is to maintain their high durability and reliability. This requirement involves taking many restrictions into account during the aircraft design process. The most important factor is the structure's overall mass, which has a crucial impact on both utility properties and cost-effectiveness. This makes aircraft one of the most complex results of modern technology. Additionally, there is currently an increasing utilization of high strength aluminum alloys, which requires the implementation of new manufacturing processes. High Speed Machining technology (HSM) is currently one of the most important machining technologies used in the aviation industry, especially in the machining of aluminium alloys. The primary difference between HSM and other milling techniques is the ability to select cutting parameters - depth of the cut layer, feed rate, and cutting speed in order to simultaneously ensure high quality, precision of the machined surface, and high machining efficiency, all of which shorten the manufacturing process of the integral components. In this paper, the authors explain the implementation of the HSM method in integral aircraft constructions. It presents the method of the airframe manufacturing method, and the final results. The HSM method is compared to the previous method where all subcomponents were manufactured by bending and forming processes, and then, they were joined by riveting.

Quality control troubleshooting tools for the mill floor

Treesearch

John Dramm

2000-01-01

Statistical Process Control (SPC) provides effective tools for improving process quality in the forest products industry resulting in reduced costs and improved productivity. Implementing SPC helps identify and locate problems that occur in wood products manufacturing. SPC tools achieve their real value when applied on the mill floor for monitoring and troubleshooting...

Field Operations and Enforcement Manual for Air Pollution Control. Volume III: Inspection Procedures for Specific Industries.

ERIC Educational Resources Information Center

Weisburd, Melvin I.

The Field Operations and Enforcement Manual for Air Pollution Control, Volume III, explains in detail the following: inspection procedures for specific sources, kraft pulp mills, animal rendering, steel mill furnaces, coking operations, petroleum refineries, chemical plants, non-ferrous smelting and refining, foundries, cement plants, aluminum…

Shear bond strength of veneering porcelain to zirconia: Effect of surface treatment by CNC-milling and composite layer deposition on zirconia.

PubMed

Santos, R L P; Silva, F S; Nascimento, R M; Souza, J C M; Motta, F V; Carvalho, O; Henriques, B

2016-07-01

The purpose of this study was to evaluate the shear bond strength of veneering feldspathic porcelain to zirconia substrates modified by CNC-milling process or by coating zirconia with a composite interlayer. Four types of zirconia-porcelain interface configurations were tested: RZ - porcelain bonded to rough zirconia substrate (n=16); PZ - porcelain bonded to zirconia substrate with surface holes (n=16); RZI - application of a composite interlayer between the veneering porcelain and the rough zirconia substrate (n=16); PZI - application of a composite interlayer between the porcelain and the zirconia substrate treated by CNC-milling (n=16). The composite interlayer was composed of zirconia particles reinforced porcelain (30%, vol%). The mechanical properties of the ceramic composite have been determined. The shear bond strength test was performed at 0.5mm/min using a universal testing machine. The interfaces of fractured and untested specimens were examined by FEG-SEM/EDS. Data was analyzed with Shapiro-Wilk test to test the assumption of normality. The one-way ANOVA followed by Tukey HSD multiple comparison test was used to compare shear bond strength results (α=0.05). The shear bond strength of PZ (100±15MPa) and RZI (96±11MPa) specimens were higher than that recorded for RZ (control group) specimens (89±15MPa), although not significantly (p>0.05). The highest shear bond strength values were recorded for PZI specimens (138±19MPa), yielding a significant improvement of 55% relative to RZ specimens (p<0.05). This study shows that it is possible to highly enhance the zirconia-porcelain bond strength - even by ~55% - by combining surface holes in zirconia frameworks and the application of a proper ceramic composite interlayer. Copyright © 2016 Elsevier Ltd. All rights reserved.

A probabilistic-based approach to monitoring tool wear state and assessing its effect on workpiece quality in nickel-based alloys

NASA Astrophysics Data System (ADS)

Akhavan Niaki, Farbod

The objective of this research is first to investigate the applicability and advantage of statistical state estimation methods for predicting tool wear in machining nickel-based superalloys over deterministic methods, and second to study the effects of cutting tool wear on the quality of the part. Nickel-based superalloys are among those classes of materials that are known as hard-to-machine alloys. These materials exhibit a unique combination of maintaining their strength at high temperature and have high resistance to corrosion and creep. These unique characteristics make them an ideal candidate for harsh environments like combustion chambers of gas turbines. However, the same characteristics that make nickel-based alloys suitable for aggressive conditions introduce difficulties when machining them. High strength and low thermal conductivity accelerate the cutting tool wear and increase the possibility of the in-process tool breakage. A blunt tool nominally deteriorates the surface integrity and damages quality of the machined part by inducing high tensile residual stresses, generating micro-cracks, altering the microstructure or leaving a poor roughness profile behind. As a consequence in this case, the expensive superalloy would have to be scrapped. The current dominant solution for industry is to sacrifice the productivity rate by replacing the tool in the early stages of its life or to choose conservative cutting conditions in order to lower the wear rate and preserve workpiece quality. Thus, monitoring the state of the cutting tool and estimating its effects on part quality is a critical task for increasing productivity and profitability in machining superalloys. This work aims to first introduce a probabilistic-based framework for estimating tool wear in milling and turning of superalloys and second to study the detrimental effects of functional state of the cutting tool in terms of wear and wear rate on part quality. In the milling operation, the mechanisms of tool failure were first identified and, based on the rapid catastrophic failure of the tool, a Bayesian inference method (i.e., Markov Chain Monte Carlo, MCMC) was used for parameter calibration of tool wear using a power mechanistic model. The calibrated model was then used in the state space probabilistic framework of a Kalman filter to estimate the tool flank wear. Furthermore, an on-machine laser measuring system was utilized and fused into the Kalman filter to improve the estimation accuracy. In the turning operation the behavior of progressive wear was investigated as well. Due to the nonlinear nature of wear in turning, an extended Kalman filter was designed for tracking progressive wear, and the results of the probabilistic-based method were compared with a deterministic technique, where significant improvement (more than 60% increase in estimation accuracy) was achieved. To fulfill the second objective of this research in understanding the underlying effects of wear on part quality in cutting nickel-based superalloys, a comprehensive study on surface roughness, dimensional integrity and residual stress was conducted. The estimated results derived from a probabilistic filter were used for finding the proper correlations between wear, surface roughness and dimensional integrity, along with a finite element simulation for predicting the residual stress profile for sharp and worn cutting tool conditions. The output of this research provides the essential information on condition monitoring of the tool and its effects on product quality. The low-cost Hall effect sensor used in this work to capture spindle power in the context of the stochastic filter can effectively estimate tool wear in both milling and turning operations, while the estimated wear can be used to generate knowledge of the state of workpiece surface integrity. Therefore the true functionality and efficiency of the tool in superalloy machining can be evaluated without additional high-cost sensing.

One of possible variants of the organization for recycling lubricate cooling of technological means for small businesses

NASA Astrophysics Data System (ADS)

Rusica, I.; Toca, A.; Stingaci, I.; Scaticailov, S.; Scaticailov, I.; Marinescu, O.; Kosenko, P.

2016-11-01

In the paper we analyze the application lubricate cooling technological environment in the processing of various materials in the past century greatly have increased cutting speed and respectively, has increased productivity [1]. Today, none of production in which anyway is used metal cutting machines of all types (milling, turning, grinding, drilling, etc.) is not without lubricant cooling technological liquid which in turn are designed to reduce cutting force and the load on metal cutting machine tools and machined parts in order to increase durability machine tools and reduce errors of processing details and also in resource energy saving. When using lubricate cooling technological environment reduces the temperature in the cutting zone resulting in higher tool life and the preservation of the surface structure being treated reducing wear of metal parts of the machine. Typically, lubricant cooling process fluids is used without replacing as long as possible not yet beginning to negatively affect the quality of process. However life expectancy lubricate cooling technological environment is limited. According to existing normative acts every kind of lubricate cooling technological environment through certain time must be deleted by from the system and subjected to a recycling. Lubricate cooling technological environment must be disposed of for the following reasons: occurs the microbial and the mechanical pollution cutting fluid, free oil impairs operational characteristics cutting fluid and increases consumption.

Fabric circuits and method of manufacturing fabric circuits

NASA Technical Reports Server (NTRS)

Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Scully, Robert C. (Inventor); Trevino, Robert C. (Inventor); Lin, Greg Y. (Inventor); Fink, Patrick W. (Inventor)

2011-01-01

A flexible, fabric-based circuit comprises a non-conductive flexible layer of fabric and a conductive flexible layer of fabric adjacent thereto. A non-conductive thread, an adhesive, and/or other means may be used for attaching the conductive layer to the non-conductive layer. In some embodiments, the layers are attached by a computer-driven embroidery machine at pre-determined portions or locations in accordance with a pre-determined attachment layout before automated cutting. In some other embodiments, an automated milling machine or a computer-driven laser using a pre-designed circuit trace as a template cuts the conductive layer so as to separate an undesired portion of the conductive layer from a desired portion of the conductive layer. Additional layers of conductive fabric may be attached in some embodiments to form a multi-layer construct.

Friction stir processing on carbon steel

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

Tarasov, Sergei Yu., E-mail: tsy@ispms.ru; Melnikov, Alexander G., E-mail: melnikov-ag@tpu.ru; Rubtsov, Valery E., E-mail: rvy@ispms.ru

2014-11-14

Friction stir processing of medium carbon steel samples has been carried out using a milling machine and tools made of cemented tungsten carbide. Samples have been machined from 40 and 40X steels. The tools have been made in the shape of 5×5×1.5 mm and 3×3×1.5 mm tetrahedrons. The microstructure of stirred zone has been obtained using the smaller tool and consists of fine recrystallized 2-3 μm grains, whereas the larger tool has produced the 'onion-like' structures comprising hard quenched 'white' 500-600 MPa layers with 300-350 MPa interlayers of bainite needles. The mean values of wear intensity obtained after measuring themore » wear scar width were 0.02 mm/m and 0.001 mm/m for non-processed and processed samples, respectively.« less

Process for Transition of Uranium Mill Tailings Radiation Control Act Title II Disposal Sites to the U.S. Department of Energy Office of Legacy Management for Long-Term Surveillance and Maintenance

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

None

This document presents guidance for implementing the process that the U.S. Department of Energy (DOE) Office of Legacy Management (LM) will use for assuming perpetual responsibility for a closed uranium mill tailings site. The transition process specifically addresses sites regulated under Title II of the Uranium Mill Tailings Radiation Control Act (UMTRCA) but is applicable in principle to the transition of sites under other regulatory structures, such as the Formerly Utilized Sites Remedial Action Program.

A microcomputed tomography evaluation of the marginal fit of cobalt-chromium alloy copings fabricated by new manufacturing techniques and alloy systems.

PubMed

Kim, Eun-Ha; Lee, Du-Hyeong; Kwon, Sung-Min; Kwon, Tae-Yub

2017-03-01

Although new digital manufacturing techniques are attracting interest in dentistry, few studies have comprehensively investigated the marginal fit of fixed dental prostheses fabricated with such techniques. The purpose of this in vitro microcomputed tomography (μCT) study was to evaluate the marginal fit of cobalt-chromium (Co-Cr) alloy copings fabricated by casting and 3 different computer-aided design and computer-aided manufacturing (CAD-CAM)-based processing techniques and alloy systems. Single Co-Cr metal crowns were fabricated using 4 different manufacturing techniques: casting (control), milling, selective laser melting, and milling/sintering. Two different commercial alloy systems were used for each fabrication technique (a total of 8 groups; n=10 for each group). The marginal discrepancy and absolute marginal discrepancy of the crowns were determined with μCT. For each specimen, the values were determined from 4 different regions (sagittal buccal, sagittal lingual, coronal mesial, and coronal distal) by using imaging software and recorded as the average of the 4 readings. For each parameter, the results were statistically compared with 2-way analysis of variance and appropriate post hoc analysis (using Tukey or Student t test) (α=.05). The milling and selective laser melting groups showed significantly larger marginal discrepancies than the control groups (70.4 ±12.0 and 65.3 ±10.1 μm, respectively; P<.001), whereas the milling/sintering groups exhibited significantly smaller values than the controls (P=.004). The milling groups showed significantly larger absolute marginal discrepancy than the control groups (137.4 ±29.0 and 139.2 ±18.9 μm, respectively; P<.05). In the selective laser melting and milling/sintering groups, the absolute marginal discrepancy values were material-specific (P<.05). Nonetheless, the milling/sintering groups yielded statistically comparable (P=.935) or smaller (P<.001) absolute marginal discrepancies to the control groups. The findings of this in vitro μCT study showed that the marginal fit values of the Co-Cr alloy greatly depended on the fabrication methods and, occasionally, the alloy systems. Fixed dental prostheses produced by using the milling/sintering technique can be considered clinically acceptable in terms of marginal fit. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

3D lattice distortions and defect structures in ion-implanted nano-crystals

PubMed Central

Hofmann, Felix; Tarleton, Edmund; Harder, Ross J.; Phillips, Nicholas W.; Ma, Pui-Wai; Clark, Jesse N.; Robinson, Ian K.; Abbey, Brian; Liu, Wenjun; Beck, Christian E.

2017-01-01

Focussed Ion Beam (FIB) milling is a mainstay of nano-scale machining. By manipulating a tightly focussed beam of energetic ions, often gallium (Ga+), FIB can sculpt nanostructures via localised sputtering. This ability to cut solid matter on the nano-scale revolutionised sample preparation across the life, earth and materials sciences. Despite its widespread usage, detailed understanding of the FIB-induced structural damage, intrinsic to the technique, remains elusive. Here we examine the defects caused by FIB in initially pristine objects. Using Bragg Coherent X-ray Diffraction Imaging (BCDI), we are able to spatially-resolve the full lattice strain tensor in FIB-milled gold nano-crystals. We find that every use of FIB causes large lattice distortions. Even very low ion doses, typical of FIB imaging and previously thought negligible, have a dramatic effect. Our results are consistent with a damage microstructure dominated by vacancies, highlighting the importance of free-surfaces in determining which defects are retained. At larger ion fluences, used during FIB-milling, we observe an extended dislocation network that causes stresses far beyond the bulk tensile strength of gold. These observations provide new fundamental insight into the nature of the damage created and the defects that lead to a surprisingly inhomogeneous morphology. PMID:28383028

3D lattice distortions and defect structures in ion-implanted nano-crystals.

PubMed

Hofmann, Felix; Tarleton, Edmund; Harder, Ross J; Phillips, Nicholas W; Ma, Pui-Wai; Clark, Jesse N; Robinson, Ian K; Abbey, Brian; Liu, Wenjun; Beck, Christian E

2017-04-06

Focussed Ion Beam (FIB) milling is a mainstay of nano-scale machining. By manipulating a tightly focussed beam of energetic ions, often gallium (Ga + ), FIB can sculpt nanostructures via localised sputtering. This ability to cut solid matter on the nano-scale revolutionised sample preparation across the life, earth and materials sciences. Despite its widespread usage, detailed understanding of the FIB-induced structural damage, intrinsic to the technique, remains elusive. Here we examine the defects caused by FIB in initially pristine objects. Using Bragg Coherent X-ray Diffraction Imaging (BCDI), we are able to spatially-resolve the full lattice strain tensor in FIB-milled gold nano-crystals. We find that every use of FIB causes large lattice distortions. Even very low ion doses, typical of FIB imaging and previously thought negligible, have a dramatic effect. Our results are consistent with a damage microstructure dominated by vacancies, highlighting the importance of free-surfaces in determining which defects are retained. At larger ion fluences, used during FIB-milling, we observe an extended dislocation network that causes stresses far beyond the bulk tensile strength of gold. These observations provide new fundamental insight into the nature of the damage created and the defects that lead to a surprisingly inhomogeneous morphology.

Synthesis of Nano-Crystalline Cu-Cr Alloy by Mechanical Alloying

NASA Astrophysics Data System (ADS)

Sheibani, S.; Heshmati-Manesh, S.; Ataie, A.

In this paper, the influence of toluene as the process control agent (PCA) and pre-milling on the extension of solid solubility of 7 wt.% Cr in Cu by mechanical alloying in a high energy ball mill was investigated. The structural evolution and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques, respectively. The solid solution formation at different conditions was analyzed by copper lattice parameter change during the milling process. It was found that both the presence of PCA and pre-milling of Cr powder lead to faster dissolution of Cr. The mean crystallite size was also calculated and showed to be about 10 nm after 80 hours of milling.

Application of Odor Sensors to Ore Sorting and Mill Feed Control

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

Michael G. Nelson

2005-08-01

Control of the feed provided to mineral processing facilities is a continuing challenge. Much effort is currently being devoted to overcoming these problems. These projects are usually described under the general headings of Mine-to-Mill Integration or Mine-Mill Optimization. It should be possible to combine the knowledge of ore type, mineralogy, and other characteristics (located in the mine modeling system), with the advanced capabilities of state-of-the-art mill control systems, to achieve an improved level of control in mineral processing that will allow optimization of the mill processes on an almost real-time basis. This is not happening because mill feed it ismore » often treated as a uniform material, when in reality it varies in composition and characteristics. An investigation was conducted to assess the suitability of odor sensors for maintaining traceability in ore production and processing. Commercially available sensors are now used in food processing, environmental monitoring, and other applications and can detect the presence of very small amounts (0.1-500 ppm) of some molecules. An assortment of such molecules could be used to ''tag'' blocks of ore as they are mined, according to their respective characteristics. Then, as the ore came into the mill, an array of ''electronic noses'' could be used to assess its characteristics in real time. It was found that the Cyranose 320{trademark}, a commercially available odor sensor, can easily distinguish among samples of rock marked with almond, cinnamon, citronella, lemon, and orange oils. Further, the sensor could detect mixtures of rocks marked with various combinations of these oils. Treatment of mixtures of galena and silica with odorant compounds showed no detrimental effects on flotation response in laboratory tests. Additional work is recommended to determine how this concept can be extended to the marking of large volumes of materials.« less

Development of the first force-controlled robot for otoneurosurgery.

PubMed

Federspil, Philipp A; Geisthoff, Urban W; Henrich, Dominik; Plinkert, Peter K

2003-03-01

In some surgical specialties (eg, orthopedics), robots are already used in the operating room for bony milling work. Otological surgery and otoneurosurgery may also greatly benefit from the enhanced precision of robotics. Experimental study on robotic milling of oak wood and human temporal bone specimen. A standard industrial robot with a six-degrees-of-freedom serial kinematics was used, with force feedback to proportionally control the robot speed. Different milling modes and characteristic path parameters were evaluated to generate milling paths based on computer-aided design (CAD) geometry data of a cochlear implant and an implantable hearing system. The best-suited strategy proved to be the spiral horizontal milling mode with the burr held perpendicular to the temporal bone surface. To reduce groove height, the distance between paths should equal half the radius of the cutting burr head. Because of the vibration of the robot's own motors, a high oscillation of the SD of forces was encountered. This oscillation dropped drastically to nearly 0 Newton (N) when the burr head made contact with the dura mater, because of its damping characteristics. The cutting burr could be kept in contact with the dura mater for an extended period without damaging it, because of the burr's blunt head form. The robot moved the burr smoothly according to the encountered resistances. The study reports the first development of a functional robotic milling procedure for otoneurosurgery with force-based speed control. Future plans include implementation of ultrasound-based local navigation and performance of robotic mastoidectomy.

Laser micromilling of convex microfluidic channels onto glassy carbon for glass molding dies

NASA Astrophysics Data System (ADS)

Tseng, Shih-Feng; Chen, Ming-Fei; Hsiao, Wen-Tse; Huang, Chien-Yao; Yang, Chung-Heng; Chen, Yu-Sheng

2014-06-01

This study reports the fabrication of convex microfluidic channels on glassy carbon using an ultraviolet laser processing system to produce glass molding dies. The laser processing parameters, including various laser fluences and scanning speeds of galvanometers, were adjusted to mill a convex microchannel on a glassy carbon substrate to identify the effects of material removal. The machined glassy carbon substrate was then applied as a glass molding die to fabricate a glass-based microfluidic biochip. The surface morphology, milled width and depth, and surface roughness of the microchannel die after laser micromilling were examined using a three-dimensional confocal laser scanning microscope. This study also investigates the transcription rate of microchannels after the glass molding process. To produce a 180 μm high microchannel on the GC substrate, the optimal number of milled cycles, laser fluence, and scanning speed were 25, 4.9 J/cm2, and 200 mm/s, respectively. The width, height, and surface roughness of milled convex microchannels were 119.6±0.217 μm, 180.26±0.01 μm, and 0.672±0.08 μm, respectively. These measured values were close to the predicted values and suitable for a glass molding die. After the glass molding process, a typical glass-based microchannel chip was formed at a molding temperature of 660 °C and the molding force of 0.45 kN. The transcription rates of the microchannel width and depth were 100% and 99.6%, respectively. Thus, the proposed approach is suitable for performing in chemical, biochemical, or medical reactions.

Comparison the Marginal and Internal Fit of Metal Copings Cast from Wax Patterns Fabricated by CAD/CAM and Conventional Wax up Techniques.

PubMed

Vojdani, M; Torabi, K; Farjood, E; Khaledi, Aar

2013-09-01

Metal-ceramic crowns are most commonly used as the complete coverage restorations in clinical daily use. Disadvantages of conventional hand-made wax-patterns introduce some alternative ways by means of CAD/CAM technologies. This study compares the marginal and internal fit of copings cast from CAD/CAM and conventional fabricated wax-patterns. Twenty-four standardized brass dies were prepared and randomly divided into 2 groups according to the wax-patterns fabrication method (CAD/CAM technique and conventional method) (n=12). All the wax-patterns were fabricated in a standard fashion by means of contour, thickness and internal relief (M1-M12: representative of CAD/CAM group, C1-C12: representative of conventional group). CAD/CAM milling machine (Cori TEC 340i; imes-icore GmbH, Eiterfeld, Germany) was used to fabricate the CAD/CAM group wax-patterns. The copings cast from 24 wax-patterns were cemented to the corresponding dies. For all the coping-die assemblies cross-sectional technique was used to evaluate the marginal and internal fit at 15 points. The Student's t- test was used for statistical analysis (α=0.05). The overall mean (SD) for absolute marginal discrepancy (AMD) was 254.46 (25.10) um for CAD/CAM group and 88.08(10.67) um for conventional group (control). The overall mean of internal gap total (IGT) was 110.77(5.92) um for CAD/CAM group and 76.90 (10.17) um for conventional group. The Student's t-test revealed significant differences between 2 groups. Marginal and internal gaps were found to be significantly higher at all measured areas in CAD/CAM group than conventional group (p< 0.001). Within limitations of this study, conventional method of wax-pattern fabrication produced copings with significantly better marginal and internal fit than CAD/CAM (machine-milled) technique. All the factors for 2 groups were standardized except wax pattern fabrication technique, therefore, only the conventional group results in copings with clinically acceptable margins of less than 120um.

Comparison the Marginal and Internal Fit of Metal Copings Cast from Wax Patterns Fabricated by CAD/CAM and Conventional Wax up Techniques

PubMed Central

Vojdani, M; Torabi, K; Farjood, E; Khaledi, AAR

2013-01-01

Statement of Problem: Metal-ceramic crowns are most commonly used as the complete coverage restorations in clinical daily use. Disadvantages of conventional hand-made wax-patterns introduce some alternative ways by means of CAD/CAM technologies. Purpose: This study compares the marginal and internal fit of copings cast from CAD/CAM and conventional fabricated wax-patterns. Materials and Method: Twenty-four standardized brass dies were prepared and randomly divided into 2 groups according to the wax-patterns fabrication method (CAD/CAM technique and conventional method) (n=12). All the wax-patterns were fabricated in a standard fashion by means of contour, thickness and internal relief (M1-M12: representative of CAD/CAM group, C1-C12: representative of conventional group). CAD/CAM milling machine (Cori TEC 340i; imes-icore GmbH, Eiterfeld, Germany) was used to fabricate the CAD/CAM group wax-patterns. The copings cast from 24 wax-patterns were cemented to the corresponding dies. For all the coping-die assemblies cross-sectional technique was used to evaluate the marginal and internal fit at 15 points. The Student’s t- test was used for statistical analysis (α=0.05). Results: The overall mean (SD) for absolute marginal discrepancy (AMD) was 254.46 (25.10) um for CAD/CAM group and 88.08(10.67) um for conventional group (control). The overall mean of internal gap total (IGT) was 110.77(5.92) um for CAD/CAM group and 76.90 (10.17) um for conventional group. The Student’s t-test revealed significant differences between 2 groups. Marginal and internal gaps were found to be significantly higher at all measured areas in CAD/CAM group than conventional group (p< 0.001). Conclusion: Within limitations of this study, conventional method of wax-pattern fabrication produced copings with significantly better marginal and internal fit than CAD/CAM (machine-milled) technique. All the factors for 2 groups were standardized except wax pattern fabrication technique, therefore, only the conventional group results in copings with clinically acceptable margins of less than 120um. PMID:24724133

Finite element simulation and Experimental verification of Incremental Sheet metal Forming

NASA Astrophysics Data System (ADS)

Kaushik Yanamundra, Krishna; Karthikeyan, R., Dr.; Naranje, Vishal, Dr

2018-04-01

Incremental sheet metal forming is now a proven manufacturing technique that can be employed to obtain application specific, customized, symmetric or asymmetric shapes that are required by automobile or biomedical industries for specific purposes like car body parts, dental implants or knee implants. Finite element simulation of metal forming process is being performed successfully using explicit dynamics analysis of commercial FE software. The simulation is mainly useful in optimization of the process as well design of the final product. This paper focuses on simulating the incremental sheet metal forming process in ABAQUS, and validating the results using experimental methods. The shapes generated for testing are of trapezoid, dome and elliptical shapes whose G codes are written and fed into the CNC milling machine with an attached forming tool with a hemispherical bottom. The same pre-generated coordinates are used to simulate a similar machining conditions in ABAQUS and the tool forces, stresses and strains in the workpiece while machining are obtained as the output data. The forces experimentally were recorded using a dynamometer. The experimental and simulated results were then compared and thus conclusions were drawn.

Cell morphology, viability, osteocalcin activity, and alkaline phosphatase activity in milled versus unmilled surface of the femoral head.

PubMed

Rhyu, Kee Hyung; Cho, Chang Hoon; Yoon, Kyung Sik; Chun, Young Soo

2016-12-01

To evaluate cellular activity in milled versus unmilled surface of the femoral head in 21 patients who underwent robot-assisted total hip arthroplasty(THA). The femoral head of 21 consecutive patients who underwent robot-assisted THA for osteonecrosis was used. 10 cc of trabecular bone from the entire milled surface was obtained using a curette. The same amount of trabecular bone was obtained at least 1 cm away from the milled surface and served as a matched control. Cell morphology, viability, osteocalcin activity, and alkaline phosphatase activity in milled versus unmilled surface were assessed. Cell morphology of the milled or unmilled surface was comparable; cells were smaller in the milled surface. Cell viability was a mean of 40% higher in the milled surface (107.4% vs. 67.2%, p<0.001); cell viability at 5 time points was comparable in each group. Osteocalcin activity of cells was slightly higher in the milled surface (1.43 vs. 1.24 ng/ml, p=0.69). Alkaline phosphatase activity of cells was slightly higher in the unmilled surface (150 105 vs. 141 789 U/L, p=0.078). The milled and unmilled surfaces of the femoral head were comparable in terms of cell morphology, viability, osteocalcin activity, and alkaline phosphatase activity.

10. Interior view of first floor showing 6 of 7 ...

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

10. Interior view of first floor showing 6 of 7 roller mills. All shown were manufactured by Allis-Chalmers. Wheel in foreground controls turbine speed. - Fisher-Fallgatter Mill, Waupaca, Waupaca County, WI

6. View of the end of the lower raceway showing ...

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

6. View of the end of the lower raceway showing the gates and controlling mechanisms for channeling water into the Industry Mill. - Industry Mill, Van Houten & Prospect Street, Paterson, Passaic County, NJ

WATER POLLUTION ABATEMENT IN THE WISCONSIN PAPER INDUSTRY

EPA Science Inventory

The study estimates the costs incurred by paper mills in the State of Wisconsin to comply with water pollution control requirements and compares these costs to those incurred by similar mills in other states.

Analysis of sugar mill effluent and its influence on germination and growth of African marigold ( Tagetes erecta L.)

NASA Astrophysics Data System (ADS)

Vaithiyanathan, Thanapal; Sundaramoorthy, Perumal

2017-12-01

Sugar industry is a very important agro-based industry in India and it discharges large amount of effluent into water bodies to create high pollution in water bodies which affects the plants and other living organisms. In the present investigation, the physico-chemical analyses of N. P. K. R. Ramaswamy co-operative sugar mill effluent was determined and impact of different concentrations (control, 10, 25, 50, 75 and 100%) of sugar mill effluent on seed germination behavior of African marigold ( Tagetes erecta L.) was studied. The morphological parameters such as germination percentage, shoot length, root length, fresh weight and dry weight of seedlings, seed vigour index, tolerance index and percentage of phytotoxicity were calculated. The results recorded for the analyses of sugar mill effluent indicated their some parameters such as PH, EC, acidity, TDS, TS, BOD, COD, sulphate, magnesium, nitrogen, zinc, iron, copper, lead, manganese and oil and grease exceeded the permissible limit compared to Tamil Nadu Pollution Control Board (TNPCB) and then germination and growth parameters increased in lower (10%) concentration of sugar mill effluent and this morphological parameters gradually decreased with increasing effluent concentration. The lower (10%) concentration of sugar mill effluent may be used for irrigation purposes.