Evaluation of Failure Behavior of a Pipe Containing Circumferential Notch-Type Wall Thinning

원주방향 노치형 감육부를 가진 배관의 손상거동 평가

  • 김진원 (조선대학교 원자력공학과) ;
  • 박치용 (한전 전력연구원 원자력연구실)
  • Published : 2003.08.01


In order to evaluate a failure behavior of pipe with notch-type wall thinning, the present study performed full-scale pipe tests using the 102mm, Schedule 80 pipe specimen simulated notch- and circular-type thinning defects. The pipe tests were conducted under the conditions of both monotonic and cyclic bending moment at a constant internal pressure of 10 MPa. From the results. of experiment the failure mode, load carrying capacity, deformation ability, and fatigue life of a notch-type wall thinned pipe were investigated, and they were compared with those of a circular-type wall thinned pipe. The failure mode of notched pipe was similar to that of circular-type thinned pipe under the monotonic bending load. Under the cyclic bending load, however, the mode was clearly distinguished with variation in the shape of wall thinning. The load carrying capacity of a pipe containing notch-type wall thinning was about the same or slightly lower than that of a pipe containing circular-type wall thinning when the thinning area was subjected to tensile stress, whereas it was higher than that of a pipe containing circular-type thinning defect when the thinning area was subjected to compressive stress. On the other hand, the deformation ability and fatigue life of a notch-type wall thinned pipe was lower than those of a circular-type wall thinned pipe.


Pipe Wall Thinning;Notch-Type Thinning;Full-Scale Pipe Test;Failure Mode


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