| 摘要 |
PURPOSE:To weld satisfactorily the lower part of metallic members without blowholes by providing a gas feeder for ejecting shielding gas toward the lower part of the weld zone of the metallic members. CONSTITUTION:A feed tip 4 is inserted to near the lower part 8a of a hood 8 between round steel bars 1 opposed to each other at a suitable spacing, and shielding gases are supplied from gas nozzles 10 and 11 into the hood 8. The entire part in the weld zone of the materials 1 is then welded while the tip 4 is oscillated and gradually moved upward. A gaseous curtain is formed in an opening 9 by the shielding gas supplied from the nozzle 11 during welding and therefore the inflow of gas such as air into the hood 8 from the outside of the hood 8 is obviated. |
