Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
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Effect of Circumferential Location of Local Well Thinning Defect on the Collapse Moment of Elbow

엘보우 붕괴모멘트에 미치는 국부 감육결함의 원주방향 위치에 대한 영향

  • Kim Jin-Weon (Department of Nuclear Engineering, Chosun University) ;
  • Lee Jang-Gon (Department of Nuclear Engineering, Chosun University)
  • 김진원 (조선대학교 원자력공학과) ;
  • 이장곤 (조선대학교 원자력공학과)
  • Published : 2005.03.01
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Abstract

The purpose of this study is to investigate the effect of circumferential location of local wall thinning defect on the collapse behavior of an elbow. Thus, the present study conducts three-dimensional finite element analysis on the 90-degree elbow containing a local wall thinning at intrados, crown and extrados of bend region and evaluates the collapse moment of wall thinned elbow under various thinning shapes and loading conditions. Combined internal pressure and bending moment are considered as an applied load. The internal pressure of $0\~20MPa$ and both closing and opening mode bending are employed. The results of analysis show that the reduction in collapse moment of the elbow by local wall thinning is more significant for a defect locating at crown than for a defect locating at intrados or at extrados. Also, the effect of internal pressure on the collapse moment of wall thinned elbow depends on the circumferential location of thinning defect and applied bending mode.

Keywords

References

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