| 摘要 |
PURPOSE:To prevent the deterioration of a bending characteristic of a joint part by providing a groove of which the depth is shorter than the thickness of a base metal on a base metal side and welding first the base metal side then welding a cladding metal thereto. CONSTITUTION:The double-Vee or other groove 2 is provided to the joint part of clad steel pipes 1, 1 having a carbon steel for the base metal 1a and a stainless steel for the cladding metal 1b. The groove depth d1 on the base metal 1a side is made shorter than the thickness t1 of the base metal 1a and the groove depth d2 on the cladding metal 1b side is made approximately equal to the thickness t2 of the metal 1b. The groove on the base metal is side is first welded of the same welding material as the base metal 1a then the groove on the cladding metal 1b side is welded of the welding material equal to or better than the cladding metal 1b. Intrusion of Cr, Ni, etc. to the weld metal at the boundary between the base metal 1a and the cladding metal 1b is prevented by the above-mentioned method. The generation of the abnormal hardness in the joint part is thus obviated and the deterioration of the bending characteristic is prevented.
|
