刚性固定法焊接工字形钢梁的焊接变形控制

Welding deformation control of steel I-beam welded by rigid fixation method

刚性固定法操作简单,但实践中设置加固位置时具有一定的盲目性,借助焊接模拟能否确定相对合理的加固位置有待于深入研究。把预测到最大焊接变形的模型作为无中间加固模型,把在最大焊接变形处设置刚性加固的模型作为有中间加固模型,基于ABAQUS有限元模拟平台,采用自编双椭球体热源模型的热源子程序DFLUX,并通过精细化网格划分方法建立有限元模型,基于顺序耦合的分析方法得到有、无中间加固模型的焊接应力场和应变场,进而比较分析两种模型在不同路径下的焊接残余应力和残余应变。结果表明在可能产生最大焊接变形处设置加固的方案,使焊接变形得到有效控制,且经济;采用合理的加固方案后,可以将焊接残余应力的增加幅度控制在较小范围内。

The rigid fixation method is simple to operate,but there is a certain degree of blindness when the reinforcement positions are set in practice.Therefore,it needs to be studied in depth whether the relatively reasonable reinforcement position can be determined with the help of welding simulation.The model that predicts the maximum weld deformation is used as the one without intermediate reinforcement,and the model with rigid reinforcement at the position of the maximum weld deformation is used as the intermediate reinforcement model.Based on ABAQUS finite element simulation platform,the heat source subroutine DFLUX is self-edited by using the dual spheroid heat source model,and the finite element model is established through the fine meshing method.The welding stress field and strain field with and without intermediate reinforcement models are obtained based on the sequential coupling analysis method.Then the welding residual stress and residual strain of the two models under different paths are compared and analyzed.The results show that the welding deformation can be controlled effectively and economically by setting reinforcement at the place where the maximum welding deformation may occur;the increase of welding residual stress can be controlled within a small range by adopting a reasonable reinforcement scheme.