| 摘要 |
PURPOSE:To decrease the content of oxygen in a weld metal by forming a nozzle which constitutes the outlet of a torch for inert gas of at least a double pipe. CONSTITUTION:An outside nozzle 14 is mounted to the outside circumferential part of, for example, an inside nozzle 1 approximately concentrically with the nozzle 1. The flow rate of the inert gas, for example, gaseous CO2 during welding is the total of the flow rate P1 of the nozzle 1 and the flow rate P2 of the outside nozzle 14 according to a welding torch having such construction and therefore a molten pool 5 is protected by a wide range of the inert gas. The content of oxygen in the weld metal is thus decreased. |
