管线钢在役焊接接头残余应力的数值模拟

摘要

The residual stress of X70 pipeline steel in-service welded joints was simulated by adopting SYSWELD software, the influence on the said welded joints residual stress of X70 pressure pipeline was studied from welding process, in-service condition and pipeline structure. The results showed that the residual stress of in-service welded joints is more complex and greater than that of conventional welding. With the heat input increasing, the residual stress of in-service welded joints increases; the flow velocity of pipeline medium increasing, the residual stress reduces. Along with pipeline pressure and outside diameter increasing, the axial residual stress near weld area reduces and the circumferential residual stress increases.%采用SYSWELD焊接模拟软件对X70管线钢在役焊接接头残余应力进行模拟,主要考察焊接工艺、在役条件和管道结构对X70压力管线在役焊接接头残余应力的影响规律.结果表明:在役焊接接头的残余应力更为复杂,且大于常规焊接.随着焊接热输入量的增加,在役焊接接头残余应力增大;增加运行管线内介质流速,接头残余应力减小;随着管道压力和管道外径的增加,近缝区轴向残余应力减小,环向残余应力增大.