方波交流等离子弧立焊主维弧干涉原因及解决措施  

Interfering mechanism of plasma arc with pilot arc and its efficient measurements in vertical-up syncrowave A. C. PAW

作　　者：郑兵[1] 王其隆[1] 王涛[1] 

机构地区：[1]哈尔滨工业大学

出　　处：《焊接学报》1995年第1期1-8,共8页Transactions of The China Welding Institution

摘　　要：本文对方波交流等离子弧焊的主、维弧相互干涉现象进行了研究。理论分析和试验结果表明：主、维弧相互干涉的原因是由于工件极性为负时反极性主电弧与维弧的电场强度、电流流向相异，使钨极和喷嘴表回聚集电荷发生或者有利于主弧（与工件为正时相比，这种有利状态的程度有所降低），不利于维弧；或者相反；或者既个利于主弧，也不利于维弧；或者对两电弧部有利的状态转变，因而导致电弧燃烧不稳定。虽然主、继弧干涉现象与双弧现象个同，但两者产生的原因相同：即都是由于喷嘴电位不能适应主电弧弧柱电场。采用与等高于主电弧极性变化相适应的断续维弧可使喷嘴电位适应主电弧电场，从而圆满地解决方波交流等离子弧焊主、维弧相互干涉问题，并可避免双弧和进一步提高焊缝成型稳定性。The interfering mechanism of plasma arc with pilot arc has been studied in Verti-cal-up syncrowave A. C. PAW in this paper. It shows that the directions of currents and cor-responding electrical fields of both plasmd arc and pilot are are opposite as the polarity ofworkpiece is changed into negative, so that the accumulating charges adjancent to the tip oftungsten and the surface of orifice will be randomly changed, which may be favourtlble forplasma arc but not for pilot arc, or on the contrary, or unfavourable for the both, or favoura-ble for the both. All the Se will make the plasma arc unstable. Although the phenomenon ofarc interference is different from that of double arc, the reason which causes the interference isthe same as that do es the double arc,i.e.the potential of nozzle is not adaptable to theelectrical field of plasma arc. The interference can be efficiently avoided by uncontinuous pi-lot arc which can make the potential of nozzle adaptable to the plasma arc,decrease the phe-nomenon of double arc and improve the stability of weld formation in keyholing PAWprocess.

关 键 词：立焊 电弧干涉 断续维弧 等离子焊 电弧焊 

分 类 号：TG456.2[金属学及工艺—焊接]