| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a working method of a metal round pipe enabling to appropriately flatten a part of an outer surface of a bend part of the metal round pipe without bringing it into a largely recessed shape. <P>SOLUTION: The working method of the metal round pipe is used for flattening a part of the outer surface of the bend part 10 by giving press work to the outer surface of the bent bend part 10 of the metal round pipe 1 with a punch 2. A pressing surface 20 formed in the front end of the punch 2 includes a pair of inclined surface parts 20a inclined so that the central part side is recessed relative to the both end sides of the pressing surface 20. In giving the press work to the outer surface of the bend part 10, the both of the pair of the inclined surface parts 20a are brought into face-to-face contact with the outer surface of the bend part 10. <P>COPYRIGHT: (C)2012,JPO&INPIT |
