To improve manufacturing yield of outer and inner rings of a bearing race, and to maintain dimensional accuracy.
The bearing steel pipe is cut substantially vertically with respect to the central axis of the bearing steel pipe at a predetermined length, so as to manufacture a cut ring. The inner and outer diameter surfaces of the cut ring are turned in predetermined diameters respectively, so as to manufacture a raw material before forging. The raw material before forging is subjected to cold forging so as to manufacture a base shape, while constraining the inner diameter surface thereof, so that the whole surface of cutting and turning surfaces has substantially forged skin finish. The base shape is separated into a base shape for an outer ring and a base shape for an inner ring of the bearing race. The predetermined surfaces of the base shapes for the outer and inner rings are made cut finish, and other surfaces thereof remain the forged skin, so as to manufacture the outer and inner rings of the bearing race.
KASAI TAKAYUKI
TAKASU ICHIRO
| JPH0386346A | 1991-04-11 | |||
| JPH0439413A | 1992-02-10 | |||
| JP2001150082A | 2001-06-05 | |||
| JP2005066606A | 2005-03-17 | |||
| JP2003194072A | 2003-07-09 |
Mizuno Katsufumi
Kawakami adult