• Transactions of Materials Processing
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• v.23 no.2
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• pp.75-81
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• 2014

Progressive dies are used for metal stamping during which multiple operations are performed in a sequence. Material is fed automatically from a coil into the press and advances from one die station to the next with each press stroke. Transfer dies are used in high-volume manufacturing for round, deep-drawn, and medium-to-large parts. Several different operations may be incorporated within a transfer die such as blanking, bending, piercing, trimming, and deep drawing. The main challenge in the current study is how to deform a seat cushion panel meeting the design specifications without any defects. A complex automation die manufacturing technology for the automotive seat cushion panel, mixing both semi-progressive die and transfer die for continuous production, was developed.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.190-195
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• 2001

The piercing and blanking of thin sheet metal working is specified division in press die design and making. In order to prevent the defects, the optimum design of the production part, strip process layout, die design, die making and try out etc. are necessary the analysis of effective factors. For example, theory and practice of metal shearing process and it's phenomena, die structure, machine tool working for die making, die materials and it's heat treatment, metal working in field, their know how etc. are included in those factors. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.146-150
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• 2000

In order to prevent the defects, the optimum design of the production part, strip process layout, die design, die making and try out etc. are necessary the analysis of effective factors. For example, theory and practice of metal shearing process and it's phenomena, die structure, machine tool working for die making, die materials and it's heat treatment, metal working in field, their know how etc. are included in those factors. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press. Part2 of this study reveals with ultra precision progressive die design, its making and tryout.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.35-39
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• 2000

The piercing and blanking of thin sheet metal working is specified division in press die design and making. In order to prevent the detects, the optimum design of the production part, strip process layout, die design, die making and try out etc. are necessary the analysis of effective factors. For example, theory and practice of metal shearing process and its phenomena, die structure, machine tool working for die making, die materials and its heat treatment, metal working in industrial and its know how etc. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press. This study regards to the aim of small quantity of production parts press working. Part 1 of this study reveals with production part and strip process layout design.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.04a
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• pp.67-70
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• 2000

The tool life is not long enough under sever forming condition in warm forging. The tool life is affected by wear heat fatigue plastic deformation and so on. Especially wear is one of the most serious factors for tool life. To increase tool life we should consider various factors like processing design die design die materials lubrication and cooling system This study design to obtain the steady state temperature of die by FEM analysis under several conditions of cooling. There are four cooling conditions in this study no cooling internal cooling external cooling and both internal and external cooling. With above obtained temperatures tool life is predicted using Archard's model that is considered softening of die. The effect of internal cooling system is better than that of externally cooled die. To predict the die life the steady state temperature is calculated by using mean temperature of die. Considering only wear the die life much longer as the cooling effect is bigger. The more accurate die life will be predicted if we consider heat crack as well as wear.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.224-228
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• 2000

The piercing and blanking of thin sheet metal working is specified division in press die design and making. In order to prevent the detects, the optimum design of the production part, strip process layout, die design, die making and try out etc. re necessary the analysis of effective factors. For example, theory and practice of metal shearing process and its phenomena, die structure, machine tool working for die making, die materials and its heat treatment, metal working in industrial and its know how etc. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press. This study regards to the aim of small quantity of production part's press working. Part 1 of this study reveals with production part and strip process layout design.

• Transactions of Materials Processing
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• v.12 no.4
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• pp.296-301
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• 2003

Though a glass tens has outstanding optical performance, it has not been widely used because manufacturing process shows poor productivity and high cost. However, press-forming method of glass lens overcomes these disadvantages with mass production. When glass lens is produced by press-forming method using closed die, it is needed that the volume of glass lens preform is precisely measured in order to prevent incomplete products and to increase in life of die. The present. paper shows the shortcoming of forming process with closed die, and performs FEM simulation of forming process with open die in order to overcome this shortcoming. The design parameters of open die are selected on the basis of assembly with optical module and maintenance of optical performance. FEM simulation is carried out with selected parameter of open die and two basic preform. According to distribution of effective strain in glass lens, optical property of glass lens formed at each set of die and preform is compared.

• Transactions of Materials Processing
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• v.9 no.2
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• pp.165-170
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• 2000

In this paper, a general approach to structural analysis of forging die sets is presented and the related design system, AFDEX/DIE, is introduced. Structural analysis of die sets is conducted by the finite element method considering both contact problem and shrink fit. In the approach, amount of shrink fit is controlled by thermal load, i.e., temperature difference between die insert and shrink rings. The loading conditions are extracted automatically from the simulation results obtained by a rigie-thermoviscoplatic finite element method. Typical application examples are given, which show the applicability of the approach and the related program.

• Transactions of Materials Processing
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• v.7 no.6
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• pp.586-593
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• 1998

In recent automotive industries there has been significant increase in applications of computer simulation to the manufacturing of stamping dies for inner and outer body panels which greatly affect durability and aesthetic quality of automobiles. Enhancement of die quality and reduction of total die manufacturing time and consequently manufacturing cost are the visible outcome. However to successfully apply the result of simulation by a commercial package to the die manufacturing development of an optimal die manufacturing process is required upon the completion of analysis of forte and shortcoming of available sheet metal forming softwares. Based on the results of numerical analysis of front door outer panel forming. this paper evaluates the applicability of simulation results to the real die manufacturing for automotive body panels. Also it attempts to select an optimal die manufacturing process including design machining and tryout. Lastly it discusses the expected effects by adopt-ing the selected process in a real stamping die manufacturing facility.

• Transactions of Materials Processing
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• v.12 no.7
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• pp.662-667
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• 2003

The dimensions of die and workpiece are changed continuously during loading, unloading, and ejecting stage. Finally, to predict precisely the dimension of forged part and get the die dimension for the net-shape components, the analysis of die and workpiece should be evaluated from the loading to ejecting. Therefore, the experimental and FEM analyses are performed to investigate the elastic characteristics at workpiece and die in the closed-die upsetting for ferrous material FE techniques are proposed to consider the unloading and ejecting stages and estimate more precisely the dimension of forged part and die. The dimensional changes fur the workpiece were evaluated quantatively during loading, unloading, and ejecting stages. The strains measured by the strain gages were compared with the estimated values by the FEM.