US 4,312,210 A · Warm forging method for cup-shaped pieces

Abstract

A method for warm forging a cup-shaped piece is disclosed. In warm forging a blank is heated between 400.degree. and 800.degree. C. and is inserted within a die having a cross sectional area substantially larger than that of the blank. The ends of the blank are clamped between a recess in the die and a recess in an upsetting punch and the upsetting punch compresses the blank until its sides become sufficiently bulged to almost touch, or touch, the sides of the die. The upsetting punch is then removed and a backward extruding punch is press fitted into the bulged blank and the blank is extruded to form a cup. The extrusion punch is lubricated and cooled by lubricant and coolant applicators at a position remote from the die so that the blank is not prematurely cooled by the coolant.

Claims11

Dependent claims

A warm forging method for a cup-shaped piece, said method comprising:

heating a blank to between 400.degree. and 800.degree. C.;
inserting said blank having side walls and a first cross-sectional area into a forging die having side walls and a second cross-sectional area equal to that of the desired cup shaped piece, said first cross-sectional area being smaller than said second cross-sectional area by an amount sufficient that a gap exists between said side walls of said blank and said side walls of said die;
clamping both ends of said blank whereby said blank is centered in said die;
upsetting said blank in said die by an upsetting punch to a degree sufficient that said wall of said blank become bulged in shape by an amount no greater than that at which said walls of said blank barely contact said side walls of said die;
press fitting a backward extrusion punch on said bulged blank in said die;
and
backwardly extruding said bulged blank in said die to form said cup shaped piece.

4 more elements

Dependencies are inferred from the claim text.

Warm forging method for cup-shaped pieces

Life of this patent

Warm forging method for cup-shaped pieces

Life of this patent

Abstract

Claims11