Optimal Design of the Tractrix Die Used in the DDI Process for Manufacturing CG Pressure Vessels

CNG 압력용기 제작을 위한 D.D.I. 공정의 Tractrix 다이 최적설계

  • Lee, Kwang O (Dept. of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Sim, Hyeon Dae (Mechanical Convergence Technology, Pusan Nat'l Univ.) ;
  • Kwak, Hyo seo (Mechanical Convergence Technology, Pusan Nat'l Univ.) ;
  • Kim, Chul (Dept. of Mechanical Engineering, Pusan Nat'l Univ.)
  • 이광오 (부산대학교 기계기술연구원) ;
  • 심현대 (부산대학교 기계융합기술학과) ;
  • 곽효서 (부산대학교 기계융합기술학과) ;
  • 김철 (부산대학교 기계기술연구원)
  • Received : 2016.05.16
  • Accepted : 2016.08.12
  • Published : 2016.10.01


Tractrix dies, used in the deep drawing process, can be used to form CNG pressure vessels without a blank holder. Previous studies had only applied tractrix profiles to perform the first deep drawing process of DDI; but an optimal design of the tractrix die that focuses on improving die life and reducing production cost has not been performed yet. In this study, finite element analyses of deep drawing processes were conducted according to heights of the tractrix die by using translating asymptotes. In addition, researchers analyzed von-Mises stresses at the part of stress concentration of the die according to the forming punch loads in order to propose an optimal tractrix die design.


Supported by : 한국연구재단


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