立向高速GMAW驼峰焊缝形成机理及抑制措施  

Formation mechanism and inhibition measures of vertical high-speed GMAW humping bead

作　　者：郭震 张理 周伟 毕贵军 韩冰 Guo Zhen;Zhang Li;Zhou Wei;Bi Guijun;Han Bing(Guangdong Institute of Intelligent Manufacturing,Guangdong Key Laboratory of Modern Control Technology,Guangzhou 510070,China)

机构地区：[1]广东省智能制造研究所,广东省现代控制技术重点实验室,广州510070

出　　处：《焊接》2020年第4期25-28,41,62,共6页Welding & Joining

基　　金：广东省科学院项目(2016GDASRC-0105,2016GDASRC-0106,2017GDASCX-0115,2018GDASCX-0115,2020GDAS YL-20200103125)。

摘　　要：文中运用自主研发的爬壁机器人焊接试验平台对立向高速熔化极气体保护焊(GMAW)驼峰焊缝进行试验研究。研究发现,立向上焊时,当焊接电流保持不变,焊接速度增加到某一临界值时,立向GMAW会产生驼峰焊缝缺陷。通过高速摄像可知,熔池中由电弧压力、熔滴冲击力和重力作用下产生动量很大的后向液体流是立向高速GMAW形成驼峰焊缝的主要原因;立向下焊时,因焊接方向和焊枪倾斜位置发生改变,熔池中由电弧压力和熔滴冲击力作用下产生的后向液体流流向与自身重力方向相反,使后向液体流的动量减小,可有效抑制驼峰焊缝的形成。试验表明,采用立向下焊工艺时,当焊接电流为200 A、焊接速度为2.4 m/min时,GMAW仍无驼峰焊缝产生,焊接效率大大提高。The humping bead in vertical high-speed GMAW was studied by welding experimental platform with the independently developed wall-climbing robot in this paper.It was found that when the welding current remained unchanged and the welding speed increased to a certain critical value,humping bead would occur during vertical upward welding process.Through high-speed photography,it could be believed that the backflow liquid flow with high momentum generated by arc pressure,droplet impact force and gravity in the weld pool was the main reason for the formation of humping bead in vertical high-speed GMAW.When the vertical downward welding was carried out,the direction of welding and the tilt position of the welding gun were changed,so that the flow direction of the backward liquid flow generated by the arc pressure and the droplet impact force in the molten pool was opposite to the direction of gravity,which could effectively suppresses the formation of the humping bead.The result showed that when the welding current was 200 A and the welding speed was 2.4 m/min,humping bead still would not appear.As a consequence,the welding efficiency was greatly improved.

关 键 词：立向高速GMAW 爬壁机器人 驼峰焊缝 立向上焊 立向下焊 

分 类 号：TG444[金属学及工艺—焊接]