To provide a method for manufacturing a pulley at the load lower than the load during the forging by the conventional manufacturing method.
The method for manufacturing the pulley includes a step of forming an intermediate-shaped pulley having the flange outside diameter (the first enlarged diameter) L1 which is larger than the blank diameter L0 in forging steps from 1(B) to (D) in the figures. The method further includes a step of applying the pressure from front and back faces of a flange part of the intermediate-shaped pulley. In this step, the pressure is locally applied to a part in the circumferential direction of the flange part of the intermediate-shaped pulley, and a pressure-applied part is successively moved in the circumferential direction of the flange part. As a result, a flange part having the second enlarged diameter L2 in which the outside diameter (the first enlarged diameter) of the intermediate-shaped flange part is further enlarged.
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