弓形半管夹套焊接工艺仿真

Simulation on welding process of bow half pipe jacket

以120°圆心角所对应的弓形半管夹套为研究对象,建立夹套与釜体简化模型,利用SYSWELD焊接软件对内外角平分线坡口及未开坡口下的夹套模型先进行传热分析,再将温度场结果输出作为残余应力场的预定义场,重点研究了半管夹套的焊接应力场的变化规律。结果表明,外角平分线坡口的弓形半管夹套根部更容易焊透,而且残余Mises应力的峰值最小;在工程中半管夹套的焊接时,应该使夹套与筒体分开一定距离,使更多的焊材能够流进焊缝处,能够减少筒体厚度方向残余应力的产生;结合焊缝3条路径上的残余应力分析得出,开外角平分线坡口的弓形半管夹套具有更好的应用性。

The arched half pipe jacket corresponding to 120°center angle was taken as the research object,and simplified model of jacket and kettle body was established.SYSWELD welding software was used to analyze heat transfer of jacket model with the inner and outer angle bisector groove and without groove,and then temperature field was output as the predefined residual stress field to study variation law of welding stress field emphatically.The results showed that the root of arcuate half pipe jacket with outer angle bisector groove was easier to weld through,and peak value of residual Mises stress was the smallest.During welding of half pipe jacket in engineering,jacket should be separated from cylinder by a certain distance,so that more welding materials could flow into weld,and residual stress in the direction of thickness of cylinder can be reduced.Combined with residual stress analysis on three paths of weld,it was concluded that arcuate half pipe jacket with outer angle bisector groove had better applicability.