焊接顺序对多焊缝干燥盘焊接残余变形的影响

Effects of welding sequence on welding residual deformation in multi-welds plate dryer

建立了干燥盘焊接的有限元模型,采用分段移动热源法对同向、对向和反向三种焊接方案共15种焊接顺序的残余变形进行了数值模拟.结果表明,干燥盘的焊接残余变形为向上的环形凸起变形,从外径到内径变形量逐渐增大,最大变形量位于内径处;反向焊接方案间隔三排的焊接顺序得到的残余变形最小,仅为同向焊接方案间隔三排的63%,是15种焊接顺序中最大残余变形量的58.8%.干燥盘直径越大,每排焊缝的间隔时间加长,各种优化方案之间的焊接变形相对量的差有所降低,可以将每排焊缝之间的冷却时间适当缩短.

The finite element model of welding in plate dryer was established. The residual deformation of different schema including forward welding,facing welding,backward welding,with total fifteen kinds of welding sequences were numerical simulated with the method of segmented moving heat source. The results show that the welding deformation of workpiece is bulging upward along the center,the welding deformation gradually increases from the outside tothe inside,the maximum deformation is in the inner part. The residual deformation of backward welding with aninterval of three rows is the minimum,which is 68%of that with forward welding with three rows interval and it is also58. 8% of the maximum residual deformation the fifteen kinds of welding sequences. The relative quantity of welding deformation in each optimized schemes is decreased appreciably while the diameter of plate dryer is bigger and the interval welding time of each rows is longer,the cooling time of each rows can be therefore shortened properly.