Forming die apparatus

A forming die apparatus for forming a hole in a predetermined region of a disk of a disk-shaped part with a shaft which has been cold-forged, and removing an outer circumferential portion of the disk, comprising:

• a lower die assembly and an upper die assembly,
• the lower die assembly including:
• a lower support base that is biased in a direction toward the upper die assembly and is movable over a predetermined range in a direction toward and away from the upper die assembly, the lower support base includes a hole defined therein that is configured to hold the shaft of the disk-shaped part;
• and a punch for forming the hole in the disk, the punch being fixed to the lower die assembly whereby the lower support base is movable relative to the punch;
• and
• the upper die assembly is movable toward and away from the lower die assembly, the upper die assembly including:
• an upper support base that is movable relative to the upper die assembly in a direction toward and away from the lower die assembly, and an upper die that is fixed to the upper die assembly whereby the upper support base is movable relative to the upper die.