Failure Analysis of Stress Reliever in Heat-Transport Pipe of District Heating System
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The objective of the present study was to perform failure analysis of double-layered bellow (expansion joint), a core part of stress reliever, used to relieve axial stresses induced by thermal expansion of heattransport pipes in a district heating system. The bellow underwent tensile or compressive stresses due to its structure in terms of position. A leaked position sufferred a fatigue with a tensile component for decades. A cracked bellow contained a higher fraction of martensitic phase because of manufacturing and usage histories, which induced more brittleness on the component. Inclusions in the inner layer of the bellow acted as a site of stress concentration, from which cracks initiated and then propagated along the hoop direction from the inner surface of the inner layer under fatigue loading conditions. As the crack reached critical thickness, the crack propagatedto the outer surface at a higher rate, resulting in leakage of the stress reliever.
Abstract
The objective of the present study was to perform failure analysis of double-layered bellow (expansion joint), a core part of stress reliever, used to relieve axial stresses induced by thermal expansion of heattransport pipes in a district heating system. The bellow underwent tensile or compressive stresses due to its structure in terms of position. A leaked position sufferred a fatigue with a tensile component for decades. A cracked bellow contained a higher fraction of martensitic phase because of manufacturing and usage histories, which induced more brittleness on the component. Inclusions in the inner layer of the bellow acted as a site of stress concentration, from which cracks initiated and then propagated along the hoop direction from the inner surface of the inner layer under fatigue loading conditions. As the crack reached critical thickness, the crack propagatedto the outer surface at a higher rate, resulting in leakage of the stress reliever.
참고문헌 (10)
- Minki Hong, "Failure Analysis of a Water Wall Boiler Tube for Power Generation in a District Heating System", Metals and Materials International, 25(5), pp.1191~1201 (2019), 대한금속·재료학회[DOI]
- 채호병, "배열회수보일러 복수예열기 부식 파손 분석", CORROSION SCIENCE AND TECHNOLOGY, 20(2), pp.69~76 (2021), 한국부식방식학회[DOI]
- 홍민기, "지역난방 배열 회수 보일러의 유동 가속 부식 원인 고찰", 한국재료학회지, 29(1), pp.11~15 (2019), 한국재료학회[DOI]
- 김영수, "지역난방 첨두부하보일러 대류부 부식 파손 분석", CORROSION SCIENCE AND TECHNOLOGY, 18(2), pp.55~60 (2019), 한국부식방식학회
- Hobyung Chae, "Stress Corrosion Cracking of a Copper Pipe in a Heating Water Supply System", Metals and Materials International, 26(7), pp.989~997 (2020), 대한금속·재료학회[DOI]
- 이형준, "지역난방수 공급관 에어벤트 부식 파손 분석", CORROSION SCIENCE AND TECHNOLOGY, 19(4), pp.189~195 (2020), 한국부식방식학회[DOI]
- 조정민, "맨홀에 설치된 지역난방 열공급관 에어벤트의 전단부 파손 원인 규명", CORROSION SCIENCE AND TECHNOLOGY, 19(4), pp.196~202 (2020), 한국부식방식학회[DOI]
- 김유섭, "지역난방 열수송관 국부 부식 파손 분석", CORROSION SCIENCE AND TECHNOLOGY, 19(3), pp.122~130 (2020), 한국부식방식학회[DOI]
- T.L. Anderson, "Fracture mechanics: fundamentals and applications" (2017), CRC Press
- H. Todoroki, "Variation of inclusion composition in 304 stainless steel deoxidized with aluminum", Iron and Steelmaker, 30, pp.60~ (2003)