| 摘要 |
PROBLEM TO BE SOLVED: To obtain the guarantee of sufficient strength characteristic in a finish product with a profitable effect by arranging a material accumulating part with an upsetting to the edge part of a disk-like blank. SOLUTION: The outer peripheral range is upsetted by feeding an upsetting roller 31 toward a rotary shaft 24 direction. By this method, a bead-like material accumulating part 12 corresponding to the shape of a circulating groove 32 is formed and this material accumulating part is formed as an asymmetrical shape to the center line of the disk-like blank 10. At the time of completing the upsetting process, the upsetting device 30 is removed from the disk-like blank and thereafter, a splitting device is shifted. The feeding of the splitting roller to the material accumulating part 12 of the disk-like blank 10 is executed in the radial direction and the disk-like blank is divided with the center of the peripheral part of the disk-like blank. By this method, a rotating symmetrical shape parts of a wheel for vehicle, etc., is manufactured with the profitable method in the cost while securing the sufficient strength. |
