苯乙烯装置膨胀节失效原因分析与对策

Analysis and countermeasures for expansion joint failure in styrene unit

国内某石化企业苯乙烯装置高温膨胀节端面环板角焊缝处产生裂纹,对裂纹产生的原因进行了分析。采用有限元分析方法,考察了保温层厚度、环板分瓣数及分瓣间距等因素对膨胀节筒体与环板结构温差及温度梯度的影响,并对膨胀节进行了设计优化,为其工程应用提供了依据,保障了苯乙烯装置的长周期稳定运行。

Cause analysis was carried out on fillet weld cracks of ring plate on the end face of high temperature expansion joint in a domestic styrene unit.By employing the method of finite element analysis,the influences brought about by insulation layer thickness,the number and spacing of ring plate on temperature difference between shell and plate of expansion joint,and temperature gradient were studied.The design of expansion joint was optimized,which provides a basis for engineering application and ensures long-term stable operation of styrene unit.