METHOD OF PRODUCING BAR BLANK Russian patent published in 2013 - IPC B21C23/01 B21J1/02 

FIELD: process engineering.

SUBSTANCE: invention relates to making metal bar blank to be used for further conversion. Proposed method comprises placing preheated bar blank in press container, process metal washer and press washer, blank premoulding and molding. Bar blank diameter equal that of process washer. Prior to heating, bar blank rear end is shaped to truncated cone with vertex angle making (1.0-1.5) of conical female die angle. Recess with surface similar to that of blank contact surface is made on process washer surface in contact with blank surface. In particular version, blank bar rear end surface and that process washer in contact therewith have coat of substance to rule out contact welding in moulding. Note here that moulding is made so that, in forming moulding residue from process washer material, time of metal displacement from peripheral point die aperture to central point die aperture equal time of metal displacement to blank rear end central point die aperture.

EFFECT: ruled out metal peeling and moulding residues, higher yield.

3 cl, 1 tbl, 3 dwg