METHOD OF REVERSE EXTRUSION AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2008 - IPC B21D25/00 

FIELD: machine building.

SUBSTANCE: method of reverse extrusion includes deformation of billet with puncheon in movable container, which is installed in matrix holder, in the process of which active friction forces are applied to billet by container movement to the side of billet metal outflow. Deformation is carried out continuously in two stages, separation of which is determined by the moment of the first cracks appearance at internal surface of billet. At the first stage active friction forces are applied to billet by means of container movement to the side of metal outflow, and at the second stage - they are transformed into reactive friction forces by container movement in reverse direction. Device for reverse extrusion consists of the top plate, on which puncheon is fixed, bottom plate with matrix holder fixed in it. Container, which is installed in matrix holder, is moved by means of two levers of the 1^st type that are installed on both sides of container. Counterpunch is installed in container with the possibility of displacement. Levers with their one end interact with movable container, and with their other end - with wedges that are installed on the top plate. Device is installed with pushers that affect lever arms that are closest to container for container displacement in reverse direction.

EFFECT: increase of produced parts quality and increase of tool resistance.

2 cl, 4 dwg, 1 ex