螺旋焊管成形过程的有限元分析

Finite element analysis of forming process of spiral welded pipes.

根据螺旋焊管成形过程中板的变形特征 ,以及焊管管壁的层间剪切残余应力 ,提出了一种特殊的单元划分方案。这种方案能在保证一定精度的情况下 ,大大减少单元和节点数 ,从而能在微机上用有限元法对螺旋焊管成形过程进行有限元数值模拟。对多种成形工况的计算结果表明 :(1)钢管的残余应力在焊接前两边比中间大 ,且自由边比递送边大 ;(2 ) 2号辊下压量h对残余应力的影响远大于板宽的影响 ,h越大 ,螺旋焊管成形过程中形成的残余应力越小 ,对于管径D =10 16mm的钢管 ,h =4 80 4mm比较合适 ;(3)

According to the deformation characteristic of the plate in the forming process of spiral welded pipes,andin cosideration of shearing residual stress in the pipe wall,a special element classification scheme is put forward.By using this scheme,the numbers of the elements and nodes can be reduced greatly with the accuracy assured;therefore the forming process of the pipe can be simulated on computers with finite element method.The results of calculation of several forming conditions show that,(1)the residual stress in the middle of the pipe is larger than that on two sides;(2)the pressing depth of the No.2 roller has greater effect on the residual stress than the plate width;(3)the residual stress produced in the forming process decreases with the increase of the plate width.