PURPOSE: To keep the strength of a welded place in an excellent state, prevent the welded place from breaking and prevent the reliability of welding from being lowered by removing dust on the outer circumference of a welding rod in advance of supplying the welding rod onto a specific position.

CONSTITUTION: A wiry welding rod 8 is wound on a rotary body 10. The rotary body 10 is fixed on a fixed part 6 freely rotating. A dragging part 14 drags the wiry welding rod 8 wound on the rotary body 10 and supplies the dragged welding bar 8 onto a specific position through a supplying hose 12 at the same time. A guiding tube part 24 to guide the wiry welding bar 8 to the dragging part 14 is installed. A dust removing means 28 is installed in advance of supplying the welding rod 8 onto the specific position, the rod is passed through a penetrating hole part 32 formed at the central part of a base part 28a of this dust removing means 28, the outer circumference the welding rod 8 is rubbed at the place of a dust removing member 30 and the dust on the outer circumference of the welding bar 8 is removed. Therefore, the strength of the welded part can be kept in the excellent state.