Transactions of the Korean Society of Pressure Vessels and Piping (한국압력기기공학회 논문집)

Korean Society of Pressure Vessels and Piping (한국압력기기공학회)
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Evaluation of the Burst Pressure for Rectangular Wall-thinning of CANDU Feeder Pipe

사각 감육을 고려한 중수로 공급자관 파열압력 평가

  • 김광수 (부산대학교 기계공학부) ;
  • 김민규 (성균관대학교 기계공학부) ;
  • 조두호 (한국원자력안전기술원) ;
  • 정재준 (부산대학교 기계공학부)
  • Received : 2021.05.14
  • Accepted : 2021.06.18
  • Published : 2021.06.30
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Abstract

The flow accelerated corrosion (FAC) is one of significant aging and degradation mechanism and can affect structural integrity of CANDU feeder pipes. Pipe burst can occur under normal operation pressure (min. 10 MPa) if wall-thinning of the feeder pipe due to FAC is accumulated. Previous studies considered simple shapes of feeder pipe with local wall-thinning in order to conservatively assess structural integrity of wall-thinned feeder pipe. In this paper, a new FE model is developed, having an actual shape of the feeder pipe (double bent) as well as the actual wall-thinning shape and location based on the in-service inspection result. Then, the burst pressure assessment of the wall-thinned feeder pipe is performed using lower bound limit load analysis considering elastic-perfectly plastic material. In addition, an improved formulation to predict the burst pressure of the wall-thinned feeder pipe is presented and the safety margin is compared with an existing assessment method.

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References

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