• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 1994년도 춘계학술대회 논문집
• /
• pp.109-117
• /
• 1994

This paper describes a method and a system for automatic generation of flanged cylinderical deep drawing process outlines. A process outline is a sequence of operation leading from the blank to the required finished part. The input is the dimension of final product and the output is the effective process outline to manufacture the product. That system is programmed by PROLOG language and is composed of facts and rules of manufacturing knowledge hierarchically.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2001년도 추계학술대회 논문집
• /
• pp.81-84
• /
• 2001

An inverse finite element approach is employed for more capability to design the optimum blank shape from the desired final shape with small amount of computation time and effort. In some drawing or stamping simulation with inverse method, it is difficult to apply inverse scheme due to the large aspect ratio or steep vertical angle of inclination. The reason is that initial guesses are hard to make out with present method for those cases. In this paper, a direct mesh marring scheme to generate initial guess on the sliding constraint surface described by finite element patches is suggested for one step inverse analysis to calculate initial blank shape. Radial type mapping is adopted for the simulation of rectangular cup drawing process with large aspect ratio and parallel type mapping for the simulation of S-Rail forming process with steep vertical angle of inclination.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2003년도 추계학술대회논문집
• /
• pp.291-295
• /
• 2003

The occurrence of ductile fracture is the working limit of many metal forming processes. It is necessary to predict the criteria and to apply the condition in a process design. Over the years. the way for clarifying conditions have been studied and presented. However such a way needs lots of experiments and analysis. In this study, in order to determine the critical damage value of a used material Cu 4N, it was performed a tensile test and FEM analysis by using DEFORM 2D. For applying the obtained critical damage value it was also performed a upsetting test by using DEFORM 2D. The way of determining a critical damage value which is presented in this study will make possible to find easily it which is one of the working limit factor. And the way of determining a critical damage value will make possible to find in multi-pass drawing process.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 1998년도 추계학술대회논문집:21세기에 대비한 지능형 통합항만관리
• /
• pp.223-238
• /
• 1998

In this study, to investigate the effect of process variables such as reduction in area, semi-die angle and the rectangular ratio to the corner filling which influences the dimensional accuracy of the final product in the drawing of the cluadrangle rod from a round bar, it has been simulated by three dimensional rigid-plastic finite element method. In order to reduce the number of simulation artificial neural network has been introduced. Also, through the experimental investigation, the present results have been implemented on the industrial product. In results, the main process variable is the combination of the semi-die angle in case of the irregular shaped drawing process and reduction in area in the event of regular shaped drawing process, respectively.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 1995년도 춘계학술대회논문집
• /
• pp.186-195
• /
• 1995

In this study, drawing process of KFP engine airsealing bearing support part is analyzed by dynamic explicit finite element method. Puckering should be supressed to meet the specification. By investigating the influence fo process parameter, the feasible process condition can be obtained. The corresponding experiment is carried out. There is good agreement between the experiment and FE simulation . From this result, it is shown that the dynamic explicit finite element method can be used effectively to avoid puckering and wrinking problem in drawing process.

• 한국정밀공학회지
• /
• 제13권1호
• /
• pp.29-37
• /
• 1996

In this study, PC controlled CNC automatic cutting system is developed. Technological introduction of the control process and the computer programming has made possible not only the automatic control for cutting processing unit but also the easy-to-use graphic software that enables the cutting process. This program involves shape part drawing and amendment, pattern reading and saving, reading Autocad file, nesting process, kerf compensation, automatic cutting path generation, NC file conversion and motor control. Software is devided into 3 modules for easy work. First step enables drawing, amendment and pattern making, followed by automatic nesting and cutting path generation with kerf compensation. In the final step, drawing data is transmitted for the resulting automatic cutting processes. This software would be applicated in gas cutting and textile cutting so that it improves the productivity of cutting process.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2007년도 추계학술대회 논문집
• /
• pp.230-233
• /
• 2007

Due to their low density, high specific strength and electromagnetic interference shielding, magnesium alloy sheets are used increasingly more often in automotive, aerospace, and electronics industries. However, magnesium ally sheets should be usually formed at elevated temperature because of their poor formability at room temperature. For the use of magnesium alloy sheets for an industrial, their mechanical properties at elevated temperature and appropriate forming process conditions have to be developed. In this study, the warm deep drawing process of AZ31 sheets is studied numerically by non-isothermal simulation. The difference between the isothermal simulation results and the non-isothermal simulation results and the progress of warm forming are discussed.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2008년도 춘계학술대회 논문집
• /
• pp.531-534
• /
• 2008

A new forming process of the large-size forging within the limit of forming loads is developed by introducing the drawing process, which usually used to apply to sheet forming. For the development of the forming process, corresponding numerical simulation are carried out. The approach is based on the Taguchi method, and utilize the DOE for design of FEM analyses. In this study, the important factors are chosen at first, and then the concept of signal-to-nose(S/N) rate is applied to evaluate the formability of large size forging-products, and each value of the design parameter is determined.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 1995년도 추계학술대회논문집
• /
• pp.128-135
• /
• 1995

Theoretical and experimental drawing characteristics for the step drawbead are discussed. The drawbead restraining forces and strains by the varous drawing angles are measured experimentally. Also, during the blank holding process, the strain distributions of upper and lower skins of specimens are analysed by the 2-D rigid-plastic F.E.M And the drawbead restraining forces and strain distributions for the drawn specimens by the drawing length are obtained by experiment.

• 소성∙가공
• /
• 제20권5호
• /
• pp.357-361
• /
• 2011

A beryllium copper alloy(C1720) sheet was stretch-drawn using different processes. A hemispherical punch was first used and the forming behavior was examined. Then, cylindrical cups with a hemispherical head were produced by either one-step drawing or two-step forming(sequential stretch forming-drawing). The one-step drawing showed the better formability than two-step forming. However, the two-step forming was the superior process in terms of attaining shape accuracy.