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.

Double-wire  /  MUP  /  Front wire  /  Rear wire  /  Axle