Forged material sizing method and apparatus

摘要

An upper die and a lower die are brought together to perform a sizing work on a roughly forged part of a primary forged article within a die cavity defined between the upper and lower dies. The lower die has a vertical through-hole directly communicated with the die cavity, and a punch is relatively movably received in the vertical through-hole in such a manner as to define jointly with the vertical through-hole an annular material flow passage. During the sizing process, a material of the roughly forge part is forced against a peripheral surface of the die cavity and excess material is allowed to flow into the annular material flow passage.

主权项

1. A method of sizing a roughly forged part of a primary forged article to produce a secondary forged article having a sized part of desired dimensional accuracy, the method comprising the steps of:
providing an upper die and a lower die relatively movable toward and away from each other and jointly defining a die cavity complementary in shape to the sized part of the secondary forged article to be produced, and a punch relatively movably received in a vertical through-hole formed in one of the upper die and the lower die in direct communication with the die cavity such that an annular material flow passage is defined between the vertical through-hole and the punch, the annular material flow passage extends away from the die cavity in a vertical direction; setting the roughly forged part of the primary forged article in the die cavity while the upper and lower dies are opened, the roughly forged part of the primary forged article being set in the die cavity so that the annular material flow passage is entirely free of any portion of the primary forged article; and bringing together the upper die and the lower die to thereby perform a sizing work on the roughly forged part of the primary forged article within the die cavity and, while keeping a closed state of the upper and lower dies and with the roughly forged part of the primary forged article being set in the die cavity with the annular material flow passage entirely free of any portion of the primary forged article, moving the upper and lower dies and the punch relatively to each other in the vertical direction to advance the punch toward the die cavity to thereby force a material of the roughly forged part against a peripheral surface of the die cavity while forcing an excess material of the primary forged article to flow into the annular material flow passage in the vertical direction away from the die cavity, thereby producing the secondary forged article with a height greater than that of the primary forged article in the vertical direction.