摘要 |
PURPOSE:To prevent a base metal component in a weld metal and in a clad steel pipe from being diluted, by joining a solid short pipe of the same component compound as a cladding material to the clad steel pipe by means of frictional welding, etc. CONSTITUTION:A solid short pipe 1 having the same component compound as a cladding material 10a is joined by frictional welding 2, and subsequently, groove work is performed for a pipe end part of the solid short pipe 1. Clad steel pipes 10, 10 prepared in said way are butted, and the periphery is welded by a welding material 4 of a co-metal with the short pipe 1. In this way, a carbon steel base metal 10b is not diluted in the weld metal 4, and the component of the solid short pipe 1 is scarcely varied, therefore, the corrosion resistance and other characteristics are not deteriorated. |