| 摘要 |
PURPOSE:To obtain a plate like annular material with high yield without waste of materials by forming a cylindrical body by bending a rectangular plate stock in a circular shape and by pressing it in a plate shape via a conical cylindrical body. CONSTITUTION:A rectangular plate stock is made by cutting a strip plate in the prescribed dimension and a cylindrical body 5 is obtd. by joining the butt end part by bending this plate stock in a circular shape. A plate like annular material 10 is then obtd. after forming it in a conical cylindrical body 9 with pressing, in the press forming die 8 equipping the lower die 7 having a conical face 7a on the inner peripheral side of the annular body and the upper die 6 having a conical face 6a on the outer peripheral side of a cylindrical body. The manufactured plate like annular material 10 is then subjected to a finishing, hardening, annealing, if necessary, grinding, etc. and used for a retainer annular material, etc.
|
