Droplet formation and motion characteristics in seven-wire rotating arc electrogas welding

This paper investigates the droplet formation and motion characteristics in seven-wire rotating arc electrogas welding. A high-speed video camera was used to observe the droplet formation and motion behaviors. The forces on the droplet in different welding parameters were analyzed to explain the droplet formation and motion processes. The results show that the small droplets at the end of six peripheral wires accumulate and grow toward the small droplet at the end of the center wire under the action of the electromagnetic force, and the coupled droplet forms under the action of electromagnetic force and surface tension at the end of the center wire. Gravity, plasma flow force, and rotating force affect the fall of the coupled droplet through the arc space and show non-axial motion and axial motion with different welding currents.