热电厂主蒸汽母管阀门焊缝裂纹原因分析  

Analysis on the Causes of Weld Cracks in the Main Steam Main Pipe Valve of a Thermal Power Plant

作　　者：孙振西[1] Sun Zhen-xi

机构地区：[1]山东省安泰化工压力容器检验中心有限公司,山东济南250000

出　　处：《化工设计通讯》2023年第9期73-75,90,共4页Chemical Engineering Design Communications

摘　　要：某化工厂主蒸汽母管焊缝在停车定检时发现了裂纹的存在,对焊缝裂纹通过宏观观察、能谱分析、金相分析及硬度检测,对裂纹的产生原因进行了分析。结果表明:阀门材料本身的特性及与管道母材壁厚的差别造成结构不连续应力集中,在介质流动的循环应力作用下形成微裂纹,停车过程中管道冷却速率过快,微裂纹扩展造成焊缝开裂,并对焊缝裂纹的预防提出了预防措施。Cracks were found in the weld seam of the main steam main pipe of a chemical plant during shutdown inspection.The causes of the cracks were analyzed through macroscopic observation,energy spectrum analysis,metallographic analysis,and hardness testing.The results indicate that the characteristics of the valve material itself and the difference in wall thickness from the pipeline base material result in discontinuous stress concentration in the structure,and microcracks are formed under the cyclic stress of medium flow.During the shutdown process,the pipeline cooling rate is too fast,and microcracks expand to cause weld cracking.Preventive measures are proposed for the prevention of weld cracking.

关 键 词：蒸汽母管 阀门 裂纹 

分 类 号：X933.2[环境科学与工程—安全科学]