It comprises cylindrical feeder collet (6) formed with a slit portion at a front end thereof for feeding power to a welding wire internally set through; collet case (7) for storing feeder collet (6) therein, having an abutment on which the end of feeder collet (6) is abutted; flexible inner tube (4) for leading the welding wire to feeder collet (6); torch body (3) with inner tube (4) inserted therein and collet case (7) detachably disposed at the front end thereof; and spring (5) for pressurizing feeder collet (6) toward the front end of the welding wire, wherein there is provided a taper surface on at least any one of the front end of feeder collet (6) and the abutment of collet case (7). Thus, it is structurally simple and applicable for a curved torch.