管道对接间断焊与连续焊的有限元分析

Finite element analysis of pipe discontinuous and continuous butt welding

应用大型有限元分析软件ABAQUS,对工业管道间断焊与连续焊的温度场和残余应力场进行数值模拟。考虑材料的物理性能随温度的变化以及外界环境对焊接构件温度场的影响,采用热振幅曲线加载方法模拟焊接热源的移动,运用单元生死技术实现管道多道焊的模拟。将两种焊接工艺得到的温度场和残余应力场进行比较。结果表明,间断焊可以降低焊接时的温度,而采用连续焊可以获得较小的轴向残余应力,间断焊和连续焊的环向应力对管道的影响不大。另外对起焊点处的温度场和残余应力场也做了详细的分析,起焊点内壁处的轴向残余应力较大。

Temperature and residual stress fields of industrial pipe discontinuous and continuous butt welding was simulated by ABAQUS.The physital properties of the material depead on the temperature,and the effects of environmental conditions on welding temperature filed,which were both considered in simulation.The heat amplitude curves loading method was applied to simulate the moving heat source.The multi-pass welding was simulated by the technique of element birth and death.A comparison of temperature and residual stress fields between discontinuous and continuous welding was carried out.Results indicated that the temperature was much lower while discontinuous welding,but lower axial residual stress can be gained by continuous welding.The annular stress of discontinuous and continuous welding did not have much affection for the pipeline.In addition,the temperature and residual stress field of starting welding point was analyzed.The inner wall residual stress was much higher in starting welding point.