국부 감육 효과가 고려된 90° Back-to-Back 배관의 선형매칭기법을 활용한 소성붕괴한계 분석 = Limit Load Analysis of 90° Back-to-Back Pipe Bends with Local Wall Thinning Using the Linear Matching Method

다국어 초록 (Multilingual Abstract)

The local wall thinning of pipe bends is frequently reported during a periodic maintenance and inspection owing to erosion or corrosion caused by fluids running inside the pipeline, and this deteriorates the structural integrity of the pipeline. To evaluate the pipe bend integrity against wall thinning, many studies have been conducted on a single pipe bend case but only a few on the 90° back-to-back pipe bends. This study evaluated the structural integrity of the 90° back-to-back pipe bend that undergoes local wall thinning by presenting the limit load boundaries using the Linear Matching Method. The limit load boundaries were created for interactions of two loads, that is, internal pressures and bending moments, and demonstrated the effect of the thinning ratio on the pipe bend integrity. The study results can provide useful insight into the design and structural integrity of the 90° back-to-back pipe bend with local wall thinning.

국문 초록 (Abstract)

각종 플랜트 설비에서 활용되고 있는 곡관(pipe bend)은 수송 유체에 의한 침식 및 부식에 의해 배관의 두께가 감소하는 국부 감육(local wall thinning)이 발생된다. 이는 배관의 구조적 건전성을 악화시키는 주된 원인이다. 현재까지 단일 곡관에 대한 연구는 활발히 진행되었으나, 두 개의 90° 곡관이 이어진 back-to-back 배관에 대한 연구는 소수의 사례만 보고되었다. 본 연구는 유한요소 해석을 이용하여 내압과 굽힘 모멘트가 작용할 때 감육이 발생한 90° back-to-back 배관의 구조적 신뢰성을 평가하였다. 배관의 감육 위치와 감육률에 따른 한계하중범위를 선형매칭기법(linear matching method)을 사용하여 규명하였다. 본 연구의 결과로 감육이 진행중인 배관의 구조건전성을 확보할 수 있으며, 설계 및 평가 측면에서도 유용한 정보를 제공해준다.

참고문헌 (Reference)

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