• 소성∙가공
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• 제7권6호
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• pp.562-569
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• 1998

The limit drawing ratio (LDR) is a major process parameter in the process design of deep drawing. If the actual drawing ratio is greater than the LDR for a particular stage then an intermediate stage has to b added the process sequence to avoid failure during the drawing operation and the optimal process design considering for the first-drawing and redrawing by using finite element method combined with ductile fracture criterion. From the results of finrte element analysis the optimal value of drawing ratio is obtained which contributes to the more uniform distribution of thickess and the smaller values of the ductile fracture infinal cup.

• 한국정밀공학회지
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• 제5권3호
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• pp.31-42
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• 1988

This paper describes a computer aided process planning system called "Deep-Drawing", "Deep-Drawing" is designed for the drawing sequence of cylindrical and rectangular cups with or without taper and flange. The computer program has written in BASIC language with personal computer. Design Rules for process planning are formulated from process limitation, plasticity theory and experimental results including the know-how of many manufacturing factories. "Deep-Drawing" Capabilities include the analysis of drawing sequence by the determination of optimal drawing ratio, the determination of intermediate shape, dimensions, punch and die radius etc., the calculation of drawing loads and blank holder force to perform each drawing step, and the graphic outputs for the operation sheet.tputs for the operation sheet.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 춘계학술대회 논문집
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• pp.82-85
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• 2002

A systematic investigation for process design in deep drawing is necessary for quality improvement of drawn cups. This study has been concentrated mainly on the influence of process design scheme on product qualities in cylindrical cup drawing. Three types of process design scheme were chosen in this study. That is, Case 1 is to finish drawing a cup of 50m in diameter in one stage, Case 2 and Case 3 are redrawing the drawn cups of 55, 65 mm in diameter to the final size respectively. Though experiments the maximum drawing force in two-stage cup drawing could be reduced up to 35% as compared with that of one-stage cup drawing. In addition, the Case 2 and Case 3 processes showed better product qualities than the Case 1 process when comparing distributions of thickness, hardness, dimensional accuracy.

• 한국정밀공학회지
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• 제15권11호
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• pp.145-151
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• 1998

Unlike the drawing of round section from round bar, the shaped drawing like polygonal section is known to have influence not only drawing stress but also corner filling. Therefore. this study analyze the drawing process of suqare rod from round bar using nonsteady state rigid-plastic FEM. To investigate effects of process variables of the drawing process of square rod from round bar, FE-simulations with variety of reduction in area and semi-die angle for a given frictional condition have been conducted. By this results, it has to suggest optimal process condition on the drawing stress and the corner filling. In addition, it has determined forming limit considering necking and bulging.

• 한국정밀공학회지
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• 제26권11호
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• pp.124-130
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• 2009

In the multi-stage shape drawing process, the most important aspect for the economy is the correct design of the various drawing stage. For most of the products commonly available round or square materials can be used as initial material. However, special products should be pre-rolled. This study proposes a process design method of multi-stage shape drawing process for producing cross roller guide. Firstly, a standard classification of shape drawing process is suggested based on the requirement of pre-rolling process. And a design method is proposed to design the intermediate die shape. The process design method is applied to design the multi-stage shape drawing process for producing cross roller guide. Finally, the effectiveness of the proposed design method is verified by FE-analysis and shape drawing experiment.

• 한국산학기술학회논문지
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• 제5권3호
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• pp.260-265
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• 2004

In order to analyze the shaped drawing process, it is necessary that the friction boundary condition between dies and blanks should be worked out the accurate numerical friction models. But, the existing numerical models of the drawing may be large different from the actual conditions. In this paper, accurate analysis of the drawing process should be subjected. It is to develop accuracy of the numerical friction models and potentialize to apply for the high speed forming work in the drawing process. Therefore, the results should improve the accuracy, cause the energy saving for the drawing process and finally expand the applying areas of the results.

• 소성∙가공
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• 제7권3호
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• pp.225-232
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• 1998

This article is aimed primarily at establishing a process planning method for complex circular shells. For the deep drawing of complex shaped shell, the optimum process design is required to reduce the trial cost improve the quality, increase the productivity and shorten the delivery. The present approach which is related to the optimum process planning is based on the empirical knowledge through trial and error in the industrial field. In order to check the validity and the effectiveness of proposed work a sample process design has been applied to the multi-stepped deep drawing of com-plex shell considering the process variables such as drawing rate radius and blank development. In particular the difference between the limiting drawing rate and to optimum drawing rate has been discussed and the usefulness of present suggestion has been shown.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1998년도 춘계학술대회논문집
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• pp.160-167
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• 1998

This article is aimed primarily at establishing a process planning method for complex circular shells. For the deep drawing of complex shaped shell, the optimum process design is required to reduce the trial cost, improve the quality, increase the productivity and shorten the delivery. The present approach which is related to the optimum process planning is based on the empirical knowledge through trial and error in the industrial field. In order to check the validity and the effectiveness of proposed work, a sample process design has been applied to the multi-stepped deep drawing of complex shell considering the process variables such as drawing rate, radius and blank development. In particular, the difference between the limiting drawing rate and the optimum drawing rate has been discussed and has been shown the usefulness of present suggestion.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 추계학술대회논문집
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• pp.273-276
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• 2003

High-temperature superconduction materials(Bi2223) possess electrical/electronic and magnetic properties. Because high-temperature superconduction materials is a ceramic powder, that can not be produced singlehandedly. So Ag sheathed Bi-2223 wire was produced by drawing process using powder-in-tube(PIT) method. This superconductor has many difficulties to produce. The main difficulty is that the mechanical properties of the ceramic powder are very different from those of the Ag sheath. Bi2223 high-temperature superconductivity have a single filament drawing process, and multi-filament drawing process. This study analysed multi-filament drawing process by FEM, a defects during multi-filament drawing was studied by FEM.

• 소성∙가공
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• 제29권2호
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• pp.97-102
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• 2020

Wire drawing is a metalworking process used to reduce the cross-section of a wire by pulling the wire through multi-stage drawing dies. The aim of this study is to fabricate a drawing wire using 2 stage drawing process. The finite element analysis of wire drawing was conducted to validate the efficiency of the designed process and the experiment was performed to validate the designed wire drawing process using 2 stage tungsten carbide die. Dry lubricant with powder was applied for producing a wire of desired diameter. Finally, a drawing wire using 2 stage die for cold rolling mill was developed.