Marine diesel engine piston external nickel-based material swing welding device

The invention discloses a marine diesel engine piston external nickel-based material swing welding device, and belongs to the welding processing equipment. The welding device comprises a driving motor, a reduction gearbox, a bracket, a welding gun clamping mechanism, a crank eccentricity adjusting mechanism and a dovetail groove type swing sliding block mechanism; in the welding process, the driving motor is used for driving a crank pin roller to slide in a sliding chute of the swing sliding block through a worm gear output shaft of the reduction gearbox and the crank eccentricity adjusting mechanism so that a dovetail sliding block inclined roller, a dovetail sliding block guide slot roller and a dovetail sliding block on the swing sliding block are capable of slipping to left or right on respective slide; and a connecting rod and the welding gun clamping mechanism connected with the swing sliding block further swing left and right. The welding device is capable of enabling the electric arc to swing slightly, the swing amplitude is not more than 3 times the diameter of a welding stick or a welding rod; and meanwhile, for overcoming the undercut defect which is capable of producing in the swing process of the electric arc, the electric arc is capable of pausing when swinging to the extreme position at each side, so that the molten metal can be used for filling in the undercut part with enough time.