Evaluating on the Effects of Circumferential Thinning Angle and Bending Load on the Failure Pressure of Wall-Thinned Elbow through Burst Tests

파열 시험을 통한 감육곡관의 손상압력에 미치는 원주방향 결함 폭과 굽힘하중의 영향 평가

  • Kim, Jin-Weon (Department of Nuclear Engineering, Chosun University) ;
  • Na, Yeon-Soo (Department of Nuclear Engineering, Chosun University) ;
  • Lee, Sung-Ho (Nuclear Mechanical and Material Group, KEPRI)
  • 김진원 (조선대학교 원자력공학과) ;
  • 나연수 (조선대학교 원자력공학과) ;
  • 이성호 (한전 전력연구원 원전기계재료그룹)
  • Published : 2006.12.31

Abstract

This study performed burst tests using real-scale pipe elbow containing simulated local wall-thinning to evaluate the effects of circumferential thinning angle and bending load on the failure pressure of wall-thinned elbow. The tests were carried out under the loading conditions of internal pressure and combined internal pressure and bending loads. Three circumferential thinning angles, ${\theta}/{\Pi}=0.125,\;0.25,\;0.5$, and different thinning locations, intrados and extrados, were considered. The test results showed that the failure pressure of wall-thinned elbow decreased with increasing circumferential thinning angle for both thinning locations. This tendency is different from that observed in the wall-thinned straight pipe. Also, the failure pressure of intrados wall-thinned elbow was higher than that of extrados wall-thinned elbow with the same thinning depth and equivalent thinning length. In addition, the effect of bending moment on the failure pressure was not obvious.

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