我厂生产的压力容器壳体的纵、环缝绝大部分均要用TIG封底焊,单面焊双面成型。对影响背面成型的几个工艺因素,我们作了如下探讨。一、组对间隙对背面成型的影响由于TIG焊速慢,加热面积较大,焊接速度小于收缩变形速度,往往造成施焊中不能保证3mm间隙,间隙的缩小,会使背面不能成型。为此,我们对各种不同间隙的背面成型情况进行了观测。 1.试验结果 I plant the pressure vessel shell vertical and horizontal seam seam are used with the vast majority of TIG back welding, single-sided welding double-sided molding. The impact on the back of the molding process several factors, we made the following discussion. First, the group of the gap on the back of the forming TIG welding slow, larger heating area, the welding speed is less than the shrinkage deformation, often resulting in welding can not guarantee the 3mm gap, the gap narrowing, will not back the molding. For this reason, we made observations on the back molding of various gaps. 1. Test results