Journal of the Society of Disaster Information (한국재난정보학회 논문집)

The Korean Society of Disaster Information (한국재난정보학회)
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The Structure Integrity Assessment of the Wall Thinned Elbow Considering In/Out-Plane Bending

열림·닫힘 방향 하중이 고려된 두께 감소된 엘보우의 건전성평가

  • Jang, Ungburm (Department Beauty of Hanse University) ;
  • Shin, Kyuin (Korea Disaster & Safety Institute) ;
  • Lee, Sungho (Central Research Institute, Korea Hydro & Nuclear Power (KHNP) Company) ;
  • Kuan, Changhee (Department Beauty of Hanse University)
  • Received : 2015.12.07
  • Accepted : 2015.12.29
  • Published : 2016.03.31
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Abstract

Local wall thinning elbow due to the water flow is one of the main degradation phenomenon in carbon steel pipe of plant system. The API579 code of FFS (fitness for service) used in the chemical plant gives a guideline to protect local wall thin problem in a straight pipe, but it does not include an elbow. In this study, the locally wall thinned elbow, which is considered an extrados or intrados wall thinned elbow, was carried out considering in-plane or out-plane bending using FEM (finite element method) analysis, and some of results were also compared with the experimental data. The results could give the structure integrity assessment to protect the local wall thinned elbow.

국부적인 두께감소 문제에 대하여 직관부위를 대상으로 한 건전성 평가는 잘 알려져 있으나 엘보우를 대상으로 한 건전성 평가는 최근에 원자력 분야에서는 많은 연구가 이루어지고 있으나 석유화학 플랜트에서 이용되는 건전성 평가 지침서 중 하나인 API579 코드에는 아직 없는 실정이다. 이에 본 연구에서는 엘보우를 대상으로 엘보우의 외부(extrados)와 내부(intrados)에 두께 감소가 있다고 가정한 후 유한요소해석법을 이용하여 두께감소된 엘부우의 건전성평가 해석을 수행하였다. 본 해석 결과는 석유화학 플랜트에서 이용되는 엘보우의 건전성 평가에 이용될 수 있음을 보여주었다.

Keywords

References

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