立向高速GMAW驼峰焊缝的试验研究  

Experimental Research on Humping Bead of Vertical High-speed GMAW

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,Guangzhou 510070;Guangdong Key Laboratory of Modern Control Technology,Guangzhou 510070)

机构地区：[1]广东省智能制造研究所,广州510070 [2]广东省现代控制技术重点实验室,广州510070

出　　处：《机械工程学报》2020年第14期73-80,共8页Journal of Mechanical Engineering

基　　金：广东省科学院资助项目(2016GDASRC-0105,16GDASRC-0106,2017GDASCX-0115,2018GDASCX-0115,2020GDASYL-20200103125)。

摘　　要：驼峰焊缝的产生严重制约了高速熔化极气体保护焊(Gas metal arc welding,GMAW)在立向焊接上的应用,目前对该技术难点研究甚少,尚无简单有效的抑制措施提出。因此,通过梳理水平高速GMAW驼峰焊缝的形成机理,以此为基础,运用自主研发的爬壁机器人焊接试验平台对立向高速GMAW驼峰焊缝进行试验研究。研究发现:立向上焊时,高速GMAW会产生驼峰焊缝缺陷,熔池中由电弧压力、熔滴冲击力和重力作用下产生的动量很大的后向液体流是形成驼峰焊缝的主要原因。此外,焊接电流和焊接速度显著影响驼峰焊缝的形貌。立向下焊时,因焊接方向和焊枪倾斜位置发生改变,使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,可有效抑制驼峰焊缝的形成。通过利用金属液体流自身重力来抑制立向高速GMAW焊接过程中驼峰焊缝的形成,大大提高了焊接速度和焊接电流,具有较高应用价值。The production of humping bead has seriously restricted the application of gas metal arc welding(GMAW)in vertical welding.At present,a little researches on this technological difficulty have been done and no simple effective suppression measures have been put forward.Therefore the formation mechanism of humping bead in the horizontal high-speed GMAW is combed,and base on which experimental research on humping bead of the vertical high-speed GMAW is conducted by the independently developed wall-climbing robot.It is found that the humping bead will occur in the vertical high-speed GMAW when the upward welding is carried out.The main reason for the formation of humping bead is the backward liquid flow generated by arc pressure,droplet impact force and gravity.In addition,the welding current and welding speed significantly influence the morphology of humping bead.When the downward welding is carried out,the direction of the welding and the tilt position of the welding torch is 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 is opposite to the direction of gravity,which can effectively suppresses the formation of the humping bead.To sum up,the gravity of metal liquid flow is used to suppress the formation of hump bead in the vertical high-speed GMAW,which greatly improves the welding speed and welding current and has great application value.

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]