管线钢在役焊接接头残余应力的数值模拟

Numerical Simulation of Residual Stress for Pipeline Steel In-service Welded Joints

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。

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.