Nuclear Engineering and Technology

  • 제52권9호
  • /
  • Pages.2092-2099
  • /
  • 2020
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  • 1738-5733(pISSN)
  • /
  • 2234-358X(eISSN)
한국원자력학회 (Korean Nuclear Society)
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The effect of crack length on SIF and elastic COD for elbow with circumferential through wall crack

  • Kim, Min Kyu (School of Mechanical Engineering, Sungkyunkwan University Full Mailing) ;
  • Jeon, Jun Hyeok (School of Mechanical Engineering, Sungkyunkwan University Full Mailing) ;
  • Choi, Jae Boong (School of Mechanical Engineering, Sungkyunkwan University Full Mailing) ;
  • Kim, Moon Ki (School of Mechanical Engineering, Sungkyunkwan University Full Mailing)
  • 투고 : 2019.11.29
  • 심사 : 2020.01.31
  • 발행 : 2020.09.25
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초록

Many damages due to flow-accelerated corrosion and cracking have been observed during recent in-service inspections of nuclear power plants. To determine the operability or repair for damaged pipes, an integrity evaluation related to the damaged piping system should be performed by using already proven code and standards. One of them, the ASME Code Case is most popularly used to integrity assessment in nuclear power plants. However, the recent version of CC N-513 still recommends the simplified method which means a damaged elbow is assumed as an equivalent straight pipe. In addition, to enhance the accuracy integrity assessment in elbow, several previous studies recommend that the SIF and elastic COD values for an elbow with relatively large crack could be predicted by an interpolation technique. However, those estimates for elbow with relatively large crack might be derived to inaccurate results for crack growth analysis, such as for the allowable crack size and life estimation. Therefore, in this paper, the effect of crack length (0.3≤θ1/π≤0.5) on SIF and elastic COD for elbow is systematically investigated. Then, for large crack in elbow, accurate estimates for SIF and elastic COD, which are widely used to assess the integrity of elbows, are proposed. Those proposed solutions are expected to be the technical basis for revisions of CC N-513-4 through the validation.

키워드

참고문헌

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피인용 문헌

  1. Segmentation Method for Enhancing the Continuity and Integrality of Microcracks in Concrete Fracture XCT Image vol.34, pp.3, 2022, https://doi.org/10.1061/(asce)mt.1943-5533.0004114