特高压开关铝罐体的变极性等离子弧焊接工艺方法

Welding procedure for aluminum-alloy tank of VPPAW welding in ultra-high voltage switchgear equipment

通过对16 mm厚5083铝合金罐体进行变极性等离子弧焊接工艺试验,分析了工艺参数变化对焊缝成形的影响,研究该铝合金罐体在不开坡口情况下分别采用氩气(需要焊前预热)和氦氩混合气作为保护气的变极性等离子弧焊接工艺,并制定出具体焊接工艺规范参数。试验结果表明,采用氦氩混合气作为保护气条件下焊接的工件,可以有效避免长焊缝预热不均、焊缝背面局部咬边等问题,同时可以降低热输入、提高焊接效率,焊缝质量达到正背面外观无缺陷、射线探伤Ⅰ级,能够满足高压开关罐体的设计要求。

The influence of welding process parameters on weld forming are analyzed by experiment on welding process of 16 mm thickness 5083 aluminum-alloy of VPPAW（variable polarity plasma arc welding） welding.Welding procedure for the aluminum-alloy tank without groove of VPPAW welding in argon shielded preheated before or helium argon mixture gas shielded was studied and the specific welding process specification was established.The results show that some defects can be avoided effectively such as uneven preheating of long weld and local undercut at the back of weld in the workpiece welded in helium argon mixture gas shielded.In addition,this welding process can decrease heat input and improve welding efficiency,the weld both face and back sides are defect-free in visul test and the weld quality attains radiographic test 1 level.It is satisfied to the design requirements of high voltage switchgear equipment.