| 摘要 |
<P>PROBLEM TO BE SOLVED: To inexpensively manufacture an oblique-bottomed cylindrical member of high dimensional precision. <P>SOLUTION: The oblique-bottomed cylindrical member (1) having a bottom part (3) slanted toward one end of a cylindrical part (2) is manufactured by a preliminarily molding process for molding a premolding (10) having an oblique face (11) by upsetting, and an aimed molding process for forging the premolding (10) to mold the oblique-bottomed cylindrical member (1). The oblique-bottomed cylindrical member (1) is virtually divided in an inclined-directional intermediate part of the bottom part by a plane passing an axis and parallel to a forging direction, a side higher in a height in the cylindrical part (2) is made to serve as a high half part, a side lower therein is made to serve as a low half part, the premolding (10) is virtually divided into the first half part corresponding to the high half part of the oblique-bottomed cylindrical member (1) and the second half part corresponding to the low half part thereof by a plane passing an axis and parallel to an upsetting direction, and a ratio of a volume of the first half part to total volume of the premolding is brought within a range of 0.9-1.2, when a ratio of a volume of the high half part to total volume of the oblique-bottomed cylindrical member is brought into 1. <P>COPYRIGHT: (C)2012,JPO&INPIT |
