| 摘要 |
PURPOSE:To form a copper plating film of a specific thickness having no diffusion and osmosis on the superposing and detaining circumferential surface side at the connecting pipe end of a steel pipe member in such a way that a part of said film remains on the surface of the superposing and detaining circumferential steel on the steel pipe member side by brazing the steel pipe member and a copper pipe member by a phosphorus copper brazing material after forming said plating film. CONSTITUTION:A steel pipe member and a copper pipe member having a relatively small diamter are superposed and detained to each other at the connecting pipe ends. A plating film of copper consisting of the >=20mu thick film formed on the superposing and detaining circumferential surface side forming the connecting pipe end on the steel pipe member side is inteposed between the superposing and detaining circumferential surface parts fitted to each other. Such superposing and detaining circumferential surface parts are brazed under heating by a phosphorus copper brazing material, by which said parts are connected. The diffusion and osmosis of the brazing material onto the copper plating film are thus limited within the plating film so that a part of the copper plating film having no diffusion and osmosis remains on the surface of the superposing and detaining steel on the steel pipe member side. |
