| 摘要 |
PROBLEM TO BE SOLVED: To provide a tube welding method and a tube welding device capable of enhancing the corrosion resistance by exerting the compressive residual stress in the axial direction in a weld metal portion on an inner face of a tube in the connection by welding tubes of large tube thickness to each other. SOLUTION: After root passes of tubes are welded, the surface of the tubes is quenched by spraying cooling water in the stage of high temperature immediately after the molten metal is solidified behind a torch to perform the welding on the outer surface of the tubes while cooling the inner surface by allowing cooling water to flow on the inner surface of the tubes. The compressive stress is generated on the outer surface side of the tubes to suppress generation of shrink-deformation in the circumferential direction of the tubes, and generate the compressive residual stress as the residual stress in the axial direction of the inner surface of the tube. COPYRIGHT: (C)2006,JPO&NCIPI |
