Plant Journal (플랜트 저널)

Korea Institute of Plane Engineering and Construction (한국플랜트학회)
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Stress Indices of Hollow Circular Cross Section Welded Attachments on Piping Elbows with the Extended Parameters Range

매개변수 적용범위를 확장한 배관 곡관부에 용접 부착된 원형관 이음부의 이차응력지수

  • Published : 2019.12.30
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Abstract

The stress concentration of the integral welded attachments (IWA) often used to support piping system has been a big issue because it induces local stresses in piping. The method to evaluate local stresses associated with attachments on elbows has been suggested in EPRI TR-107453. However, there are limitations regarding specific parameters range in order to use correlation equation. In this paper, parametric study based on piping elbow size and attachment dimension was performed utilizing finite element analysis (FEA) to evaluate the secondary stress indices of hollow circular cross section welded attachments on piping elbows with the extended parameters range. The results of the FEA were used to develop correlation formulas for calculating secondary stress indices. The empirical equations in this study are suggested as an alternative evaluation method of EPRI TR-107453 by extending parameters range.

배관계를 지지하는 목적으로 자주 사용되는 일체형 용접부착물은 응력집중효과로 인한 국부응력을 유발시켜 종종배관의 파손을 일으키기 때문에 사용에 각별한 주의를 요구하고 있다. 국내 원자력 발전소 배관 곡관부에 부착된 원형관의 국부응력 평가는 EPRI TR-107453에 따라 평가하고 있지만, 이의 적용에는 배관과 부착물의 크기에 관한 특정 매개변수 범위의 제한사항이 있다. 이 논문에서는 유한요소해석을 활용하여 모델들의 치수를 기반으로 한 매개변수 연구를 수행하여 기술적 근거를 확립하고 연구 결과에 대한 회귀분석을 통해 확장된 매개변수 범위를 갖는 곡관부에 부착된 원형관 이음부의 이차응력지수 산출 상관관계식을 도출하였다. 본 연구를 통해 개발된 새로운 상관관계식에 대한 검증을 통해 현재 평가기준의 대체 기준으로써 적용할 것을 제안한다.

Keywords

References

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