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Forging Die Design for Vent Forming of Square Cup Battery Case

사각 컵 배터리 케이스 바닥 벤트 성형을 위한 단조 금형 설계

  • Lee, Sang-Hoon (Department of Metal Mold Design Engineering, Kongju National University) ;
  • Kwon, Soon-Ho (Department of Metal Mold Design Engineering, Kongju National University) ;
  • Chung, Hoon (Sangsin EDP) ;
  • Hong, Seokmoo (Department of Metal Mold Design Engineering, Kongju National University)
  • 이상훈 (국립공주대학교 금형설계공학과) ;
  • 권순호 (국립공주대학교 금형설계공학과) ;
  • 정훈 (상신이디피(주)) ;
  • 홍석무 (국립공주대학교 금형설계공학과)
  • Received : 2017.03.02
  • Accepted : 2017.06.09
  • Published : 2017.06.30

Abstract

The demand for electric motor fuel cells has surged in the automotive industry, leading to a recent increase in the demand for square aluminum cans used as fuel cell battery casings. The air vent located on the bottom of the rectangular battery casing prevents large explosions by intermittent pressure release prior to the accumulation of abnormally high pressures. Conventionally, the square cup battery casing is produced via six-step deep drawing, with the outer shape of the vent being manufactured by welding to the square battery casing. On the other hand, this study directly incorporated the air vent outlet into the bottom surface of the rectangular casing. The product of a coupled finite element analysis technique applying the thickness and contour generated from the square cup multi-step deep drawing formation analysis was used as the forging input shape. The results yielded increased prediction accuracy and the advanced prediction of defects, such as swelling and fracture. Based on the results of the initial analyses, two of the generated forging shapes were determined to be suitable, with the optimal forging shape being determined by molding analysis. The results presented here were validated by mold fabrication and a subsequent comparison of the actual and analytical results.

Keywords

Cold Forging;Finite Element Analysis;Square Cup Battery Case;Vent Forming;Welding process

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