| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a pedestal mounting rotating ring excellent in a rational way and productivity by bending and straightening a rolled material having a required cross sectional shape beforehand and to provide its pedestal. SOLUTION: A rolled steel material, which has an integrated cross section of a collar shaped part 11 to be a pedestal mounting rotating ring and a cylinder part 12 having a required shape, is used, by bending into an annular shape of a required diameter and welding butting parts of the annular shape, an intermediate product (work a) is obtained, successively, expanding of an inner diameter part/he collar part by an expanding die 20A/a punch 23 and pressing by a pressing piece 37 for the collar shaped part 11 are conducted using a press machine to correct roundness and flatness, thus, a product is obtained.
|
