SACTIG与VPTIG电弧稳定性的对比分析(二)

Comparison of stability between SACTIG and VPTIG arc(Ⅱ)

利用高速录像系统、焊接电弧测试分析仪同步实时采集正弦交流TIG(SACTIG)和变极性TIG(VPTIG)焊接电流、电弧电压、电弧形态信息,以再引弧过程中两电极空间气体的平均电导变化率为判据,建立了VPTIG电弧稳定性数学模型;比较分析了SACTIG与VPTIG焊接电流过零期间,焊接电弧稳定性与相关电学参数之间的关系。试验表明,VPTIG与SACTIG电弧本质上同属ACTIG电弧,虽然两者相关电学参数对电弧稳定性影响的规律方面是一致的;但是VPTIG与SACTIG电弧在产热、散热、极性转变特性、焊接电源空载电压、焊接电流波形等方面存在差别,两者电弧稳定性表现出许多不同特点。VPTIG和SACTIG焊接电弧稳定性分别随VPTIG焊接电源施加在两电极之间空载电压的上升斜率和SACTIG电源空载电压频率增大而提高;再引弧电压Ur越高电弧越不稳定;焊接电源空载电压越高电弧越稳定;焊接电流越大电弧越稳定。

The welding current,arc voltage and shape in sine alternative current TIG(SACTIG) and variable polarity TIG(VPTIG) welding were collected by highspeed camera system and welding arc analyzer.Electrical arc stability model of VPTIG was established based on the variance ratio of average conductance of arc,the relationship between welding arc stability and relevant parameters was compared and analyzed during the welding current to zero of SACTIG and VPTIG.The research showed that the arcs of VPTIG and SACTIG es...