20钢管A-TIG大钝边打底焊法

Largeblunt edge root welding method for A-TIG of 20 steel pipe

利用手工A-TIG焊对20钢管进行了大钝边打底焊研究。钝边尺寸及装配间隙合理时,在适当工艺参数支持下,可实现活性TIG焊全位置大钝边打底焊接。活性剂作用下熔池表面张力方向的改变是影响A-TIG全位置大钝边打底焊成型的重要因素。平焊位置,内表面张力σ2是平衡向下的重力G与电弧力Fa的重要作用力;立焊位置,内表面张力σ2是平衡水平电弧力Fa主要作用力;仰焊位置,外表面张力σ1与内表面张力σ2是克服重力G的重要作用力。

A study was conducted on the large blunt edge root welding of 20 steel pipes using manual A-TIG welding.When the size of the blunt edge and the assembly gap are reasonable,with the support of appropriate process parameters,A-TIG welding with full position large blunt edge root can be achieved.The change in surface tension direction of the molten pool under the action of an activator is an important factor affecting the formation of A-TIG full position large blunt edge root welding.In the flat welding position,the inner surface tensiono 2 is the important force that balances the downward gravity G and the arc force Fa;At the vertical welding position,the inner surface tensiono 2 is the main force that balances the horizontal arc force Fa;At the overhead welding position,the outer surface tension o 1.Internal surface tension o2 is an important force to overcome gravityG.