1Cr5Mo管法兰焊缝在线开裂失效原因分析  

On-line cracking failure analysis of 1Cr5Mo pipe flange weld

作　　者：卢一城 LU Yicheng(Fujian Fefining&Petrochemical Co.,Ltd.,Quanzhou 362000,Fujian,China)

机构地区：[1]福建联合石油化工有限公司,福建泉州362000

出　　处：《金属加工（热加工）》2024年第5期25-29,共5页MW Metal Forming

摘　　要：石化装置因压力管道泄漏而不能正常运行,对主要影响因素管法兰开裂焊缝进行追查,并对管法兰开裂焊缝进行失效分析。经过对泄漏管法兰试件的观察与分析,管法兰焊缝热影响区出现开裂,且开裂模式为脆性延迟断裂,机理为应力腐蚀开裂。发生应力腐蚀的原因应是由于焊缝热影响区组织存在淬硬马氏体,导致硬度严重超标,在湿硫化氢作用下产生应力腐蚀开裂。淬硬马氏体的形成应与焊后热处理质量和检测质量有关。The leakage of pressure pipeline in petrochemical plant can not work normally,the main influencing factors of cracking weld of pipe flange are traced,and the failure analysis of cracking weld of pipe flange is carried out.Through the observation and analysis of the leaking pipe flange specimen,the heat affected zone of the pipe flange weld cracks,and the cracking mode is brittle delayed fracture,and the mechanism is stress corrosion cracking.The stress corrosion is caused by the existence of quenched martensite in the weld heat affected zone,which leads to the hardness exceeding the standard seriously,and the stress corrosion cracking occurs under the action of wet hydrogen sulfide.The formation of hardened martensite should be related to the quality of welding heat treatment and testing.

关 键 词：法兰焊缝 失效分析 改进措施 

分 类 号：TE96[石油与天然气工程—石油机械设备] TG441.7[金属学及工艺—焊接]