Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Process Design of the Hot Pipe Bending Process Using High Frequency Induction Heating

고주파 유도가열을 이용한 열간 파이프 벤딩 공정 설계

  • Ryu, Gyeong-Hui (Graduate School of Busan National University) ;
  • Lee, Dong-Ju (Graduate School of Busan National University) ;
  • Kim, Dong-Jin (Sheet Products Process Research Group, Busan National University) ;
  • Kim, Byeong-Min (Sheet Products Process Research Group, Busan National University) ;
  • Kim, Gwang-Ho (Dept. of Inorganic Mat. Eng., Pusan National University)
  • 류경희 (부산대학교 대학원) ;
  • 이동주 (부산대학교 대학원) ;
  • 김동진 (부산대학교 정밀정형 및 금형가공 연구소) ;
  • 김병민 (부산대학교 정밀정형 및 금형가공 연구소) ;
  • 김광호 (부산대학교 무기재료공학과)
  • Published : 2001.09.01
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Abstract

During hot pipe bending using induction heating, the wall of bending outside is thinned by tensile stress. In design requirement, the reduction of wall thickness is not allowed to exceed 12.5%. So in this study, two methods of bending, one is loading of reverse moment and the other is loading of temperature gradient, have been investigated to design pipe bending process that satisfy design requirements. For this purpose, finite element analysis with a bending radius 2Do(outer diameter of pipe) has been performed to calculate proper reverse moment and temperature gradient to be applied. Induction heating process has been analyzed to estimate influence of heating process parameters on heating characteristic by finite difference method. Then pipe bending experiments have been performed for verification of finite element and finite difference analysis results. Experimental results are in good agreement with the results of simulations.

Keywords

References

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