EO/EG装置塔进料线法兰裂纹分析  

Crack Analysis of a Tower Inlet Line Flange in an EO/EG Unit

作　　者：曾李国 段志宏[2] Zeng Liguo;Duan Zhihong(Zhongke(Guangdong)Refinery&Petochemical Company Limited,Zhanjiang 524076,China;Guangdong University of Petrochemical Technology,Maoming 525000,China)

机构地区：[1]中石化中科(广东)炼化有限公司,广东湛江524076 [2]广东石油化工学院,广东茂名525000

出　　处：《广东化工》2024年第13期81-84,共4页Guangdong Chemical Industry

摘　　要：某石化企业的EO/EG装置乙二醇脱水塔进料线法兰发生断裂失效,为了确定其失效原因,对其进行了宏观观察,并对法兰取样进行宏观观察、硬度试验、化学成分分析、力学性能分析、金相实验、扫描电镜和能谱分析等表征手段。结果表明:该EO/EG装置法兰裂纹为氯化物应力腐蚀疲劳裂纹,裂纹首先启裂于法兰内壁面加工刀痕、打磨凹痕和焊疤等应力集中部位,并在交变载荷和氯化物应力腐蚀开裂的作用下向外壁扩展,直至穿透泄漏。为此应加强制造和安装质量控制,并控制介质中氯离子含量,以保障法兰的安全运行。In a petrochemical enterprise's EO/EG unit,the inlet line flange of the glycol dehydration tower experienced fracture failure.In order to determine the cause of this failure,a series of characterizations were conducted,including macroscopic observation,hardness testing,chemical composition analysis,mechanical property analysis,metallographic examination,scanning electron microscopy(SEM),and energy dispersive spectroscopy(EDS).The results show that the flange crack in the EO/EG unit is due to chloride-induced stress corrosion fatigue.Specifically,the crack initiates at stress concentration sites such as machining marks,grinding indentations,and weld scars on the inner wall surface of the flange.Subsequently,it propagates outward under alternating loads and chloride stress corrosion cracking,eventually penetrating and causing leakage.Therefore,to ensure the safe operation of the flange,it is necessary to enhance manufacturing and installation quality control and to control the chloride ion content in the medium.

关 键 词：EO/EG装置 失效分析 法兰 裂纹 氯化物应力腐蚀开裂 

分 类 号：TE62[石油与天然气工程—油气加工工程]