Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Prediction of Air Pocket Pressure in Draw Die during Stamping Process

드로우 금형의 에어포켓 수축에 따르는 내부공기 압력예측에 대한 연구

  • Koo, Tae-Kyong (School of Mechanical Engineering, Pusan National University) ;
  • Hwang, Se-Joon (School of Mechanical Engineering, Pusan National University) ;
  • Park, Warn-Gyu (School of Mechanical Engineering, Pusan National University) ;
  • Oh, Se-Wook (Hyundai Motor Company)
  • Published : 2008.11.01
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Abstract

Metal stamping is widely used in the mass-production process of the automobile industry. During the stamping process, air may be trapped between the draw die and the panel. The high pressure of trapped air induces imperfections on the panel surface and creates a situation where an extremely high tonnage of punch is required. To prevent these problems, many air ventilation holes are drilled through the draw die and the punch. The present work has developed a simplified mathematical formulation for computing the pressure of the air pocket based on the ideal gas law and isentropic relation. The pressure of the air pocket was compared to the results by the commercial CFD code, Fluent, and experiments. The present work also used the Bisection method to calculate the optimum cross-sectional area of the air ventilation holes, which did not make the pressure of the air pocket exceed the prescribed maximum value.

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References

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