| 摘要 |
An equipment and a method for welding a stainless steel pipe are provided to allow the welding bead part and the heat affected zone of the steel pipe to maintain the same physical properties such as hardness and corrosion resistance as those of a base metal of the steel pipe by preventing oxidation of weldments during TIG welding or plasma welding of the steel pipe and enabling a welding bead part and a heat affected zone to achieve a solid solution treatment effect at the same time. An equipment for welding a stainless steel pipe(10) comprises: a welding machine for ejecting argon gas for oxygen shielding into the opening while melting one of a base metal and a welding material(30) in an opening between steel pipe rolled up in a circular shape; and a gas supply pipe(70) on which an ejection nozzle(70a) is formed, the ejection nozzle being installed in the steel pipe to eject 4 to 20 L/min of the argon gas toward an inner face of an already welding-completed welding bead part(30a) distanced backward in a predetermined distance from a welding bead part on which welding is being proceeded by the welding machine, wherein the ejection nozzle is positioned at a position that is 5 to 8 mm distanced backward from the welding bead part that is being welded by the welding machine. |
