| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a flat tube capable of reducing the amount of a brazing filler metal flowing inside when manufacturing the flat tube. SOLUTION: A suspension of a flux consisting of KAlF<SB>4</SB>is applied on a brazing filler metal layer on a surface on the raised side of a projecting bar for a side wall in upper and lower wall forming parts 21 of a plate-like body 20 for manufacturing a flat tube to manufacture the flat tube. A suspension of a mixed flux with at least any kind of KAlF<SB>4</SB>, LiF, KZnF<SB>3</SB>and ZnF<SB>2</SB>is applied on a brazing filler metal layer on a surface on the raised side of a projecting bar for the side wall in a covering wall forming parts 24. After the projecting bars 9 for the side wall are folded in a hair-pin shape on both sides of a connection part of the plate-like body 20 for manufacturing the flat tube and butted to each other, the covering wall forming part 24 is folded to obtain a folded body along outer surfaces of both projecting bars 9 for side walls. The folded body is heated to a predetermined temperature, and fore ends of both projecting bars 9 for the side wall are brazed to each other, and the covering wall forming part 24 is brazed to both projecting bars 9 for the side wall. COPYRIGHT: (C)2008,JPO&INPIT |
