一种高效预测厚壁管件焊接变形的有限元模拟方法

摘要

Analysis of simplifications that can be applied to butt welding for the thick-walled pipes based on SYSWELD software was discussed.The computation efficiency was improved and the results show the error of displacement-field was small by reducing dimensions and simplifing heat source model.An efficient FE simulation method for predicting welding distortion of thick-walled pipes is provided for practice.The computed results show that there is an obvious axial distortion in thick-walled pipes butt welding and the main stage of shrinkage is early stage of welding.As the welding quantity reaches the 20 mm approximately,the rigidity of structure can limit the axial shrinkage to some extent and the shrinkage becomes slow.Based on computed efficiency,computed results and experimental results.A FE simulation method is available that applying given-temp heat source model in 2D axisymmetric structure can effectively predict the welding distortion of thick-walled pipes.%基于SYSWELD软件讨论并分析了厚壁管件结构对接焊的数值模拟简化方式,通过降低维数、简化热源模型等方式快速计算得到误差较小的位移场结果,总结出一种具有实际工程应用意义的高效预测厚壁管件焊接变形的有限元模拟方法.计算结果表明,厚壁管件焊接存在明显的轴向变形,焊接初期是轴向收缩的主要阶段,当焊接量达到20 mm左右时,受结构刚度限制,轴向收缩量逐步变缓.结合计算效率、计算结果和试验数据,采用给定热源模型的二维模型基本符合工程应用要求,能够实现高效预测具有三维效应管件焊接变形的目的.