WELDING DEVICE AND WELDING METHOD

According to some embodiments, there is provided a welding device for welding outer peripheral edges of overlapping two irregular shaped plates, including a rotary table to which the overlapping two irregular shaped plates are fixed, a torch unit including a welding torch positioned to face the outer peripheral edges of the two irregular shaped plates fixed to the rotary table, a first torch actuator capable of changing an orientation and a distance of the welding torch relative to the outer peripheral edges, and a first controller configured to control the first torch actuator so that the orientation of the welding torch relative to a tangential line of the outer peripheral edges and the distance of the welding torch from the outer peripheral edges are kept constant along a circumferential direction of the outer peripheral edges, during rotation of the two irregular shaped plates.