Patent ID: 6591654
Filing Date: 2003-07-15
Classification: B21C

Abstract:
An extrusion die set for use in conjunction with a single cylinder horizontal extrusion press which forces a billet of metal through said die set in an extrusion direction, said die set comprising:a charging die comprising: a plurality of separate substantially identical charge distribution passages symmetrically arranged around a central axis, each said charge distribution passage traversing an arcuate path from an inlet to an angularly offset outlet; a mixing extension axially projecting in the extrusion direction and at least partially surrounded at a charging end by said charging passages; and a mandrel integrally connected to said mixing extension, and a forming die defining an axial opening leading in the extrusion direction to a forming ring, said forming die configured to mate with said charging die and receive said mixing extension and mandrel to determine an axially continuous, substantially tubular charge flow passage comprising: an annular mixing chamber in communication with said charge distribution passage outlets, said mixing chamber having a radial dimension and terminating in the extrusion direction in an annular exit having a radial dimension substantially less than the radial dimension of the mixing chamber; a mixing space defined between said mixing extension and said forming die beyond said annular exit in the extrusion direction, said mixing space in communication with said annular exit, said mixing extension and said forming die being configured so that said mixing space has a continuously variable internal configuration in the extrusion direction; and an extrusion orifice defined between said forming ring and said mandrel, said extrusion orifice in communication with said mixing space.