双丝MUP控制技术在桥壳焊接中的应用研究

Research on the Application of Double-Wire MUP Control Technologies in Bridge Shell Welding

为保证焊接焊缝计算深度、降低热输入量、提高焊接速度,开发了双丝混合脉冲(MUP)焊接工法用于重型载货汽车车桥配套机器人双丝焊接。设计开发了4种模式进行焊接控制,并从电弧稳定性、热输入、波形控制方面进行了分析对比。模式1为前丝脉冲焊接后丝MUP工法焊接、模式2为前丝MUP工法焊接后丝纯脉冲焊接、模式3前后丝均为MUP工法焊接,前丝脉冲对应后丝脉冲,前丝直流对应后丝直流、模式4前后丝均为MUP工法焊接,前丝脉冲对应后丝直流,前丝直流对应后丝脉冲。在车桥纵缝V形坡口焊接时使用模式1可以获得均匀一致的焊缝计算深度,减小热输入量提高了焊接速度,焊缝成形也较为美观;模式2较适合于薄板快速焊接的应用场合;当焊接车桥加强圈和后壳时,使用模式3可以显著降低热输入获得美观的焊缝、提高电弧的稳定性及焊接速度;模式4适合于厚板填充层的焊接,可搅拌熔池促进气体快速溢出,降低焊缝气孔倾向。

To ensure the calculation depth of the weld seam,reduce the heat input and improve the welding speed,a double-wire MUP welding method was developed for robot double-wire welding of the heavy truck axle.4 welding control modes were developed,which were analyzed and compared in aspects of arc stability,heat input and waveform control.Mode 1 is front welding wire pulse welding plus rear wire Mixed Up Pulse(MUP)welding,Mode 2 is front wire MUP welding plus rear wire pure pulse welding,Mode 3 is MUP welding for both front and rear wires,front wire pulse corresponds to rear wire pulse and front wire DC corresponds to rear wire DC,mode 4 is MUP welding for both front and rear wires,front wire pulse corresponds to rear wire DC and front wire DC corresponds to rear wire pulse.When welding the axle longitudinal seam V-shaped groove,the use of Mode 1 can obtain consistent weld seam calculation depth,reduce the heat input,improve welding speed and obtain graceful weld seam appearance;Mode 2 is more suitable for rapid welding of thin plates,the use of Mode 3 can significantly reduce heat input to obtain graceful weld seam,improve arc stability and welding speed when welding axle reinforcement ring and rear axle housing,and Mode 4 is suitable for the welding of thick plate filling layer,which can stir the molten pool to promote rapid gas overflow and reduce the tendency of porosity in the weld.