ANORDNING OCH FORFARANDE FOR VARMSMIDNING

摘要

An apparatus and method of hot-forging in a forging press a cylindrical powdered metal preform to substantially full theoretical density to thereby produce a powdered metal part having a small inner bore wherein the core rod defining such bore is constructed so as to allow a continuous flow of a highly vaporizable liquid coolant such as nitrogen to the metal forming portion of the core rod and to thermally insulate the incoming coolant to assure its being maintained substantially unvaporized until being expelled to the core rod cooling chamber.