Extrusion press die assembly

Abstract

Systems, devices, and methods for continuous extrusion of material billets are provided. A die assembly for press extrusion of a material includes a plurality of die plates forming a die body. The die body has an entrance and an exit having a diameter smaller than the entrance, with a tapered surface between the entrance and the exit. Each die plate has a center bore with a tapered interior surface, and the interior surfaces form the tapered surface that extends from the entrance to the exit. A base is coupled to the die body, and rotation of the base causes rotation of the die body. A billet pressed into the die body is heated by friction between the interior surface and an outer surface of the billet. The billet is heated to a deformable temperature and is extruded into a tube product as the billet is pressed from the entrance to the exit of the die body.

1 . A die assembly for extruding a material, comprising:
 a plurality of die plates coupled together to form a die body having:   a passage defining an entrance and an exit, wherein the diameter of the exit is smaller than the diameter of the entrance; and   a tapered interior surface between the entrance and the exit;   wherein each of the die plates has a center bore with an interior surface around the center bore, an interior surface of a center bore in a first die plate being tapered at a smaller angle relative to an axis of the passage than an interior surface of a center bore in a second die plate positioned adjacent to a front face of the first die plate; and   a base coupled to the die body, wherein rotation of the base causes the die body to rotate.   
     
     
         2 . The die assembly of  claim 1 , wherein the second die plate is positioned nearer to the entrance of the die body than the first die plate. 
     
     
         3 . The die assembly of  claim 1 , further comprising a third die plate having a center bore with an interior surface that is tapered at a larger angle relative to the axis than an interior surface of a center bore in a die plate positioned adjacent to a front face of the third die plate. 
     
     
         4 . The die assembly of  claim 3 , wherein the die plate positioned adjacent to the front face of the third die plate is the first die plate. 
     
     
         5 . The die assembly of  claim 3 , wherein the third die plate is positioned nearer to the exit of the die body than the first die plate. 
     
     
         6 . The die assembly of  claim 1 , further comprising a third plate that forms a portion of the die body, the first plate having a central bore with an interior surface around the center bore that is not tapered at an angle relative to the axis. 
     
     
         7 . The die assembly of  claim 6 , wherein the center bore of the third plate defines the entrance of the die body. 
     
     
         8 . The die assembly of  claim 1 , wherein the base comprises a center bore. 
     
     
         9 . The die assembly of  claim 8 , wherein the center bore of the base has a diameter that is greater than a diameter of the die body exit. 
     
     
         10 . The die assembly of  claim 1 , wherein the die body is configured to receive a billet of material for extrusion, and the billet is not pre-heated before entering the die body. 
     
     
         11 . The die assembly of  claim 10 , wherein rotation of the die body creates friction between the tapered interior surface and a billet advanced through the entrance and into the interior passage of the die body. 
     
     
         12 . The die assembly of  claim 11 , wherein the friction heats the billet to a temperature that is sufficient to cause deformation of the billet material. 
     
     
         13 . The die assembly of  claim 12 , wherein the heated billet is deformable under a deformation force that does not exceed mechanical property limits of the billet material. 
     
     
         14 . The die assembly of  claim 13 , wherein friction between the billet and a mandrel over which the billet is advanced heats the billet and the mandrel. 
     
     
         15 . The die assembly of  claim 14 , wherein a cooling system provides cooling fluid to an interior portion of the mandrel. 
     
     
         16 . The die assembly of  claim 1 , wherein at least one of the die plates is formed from two different materials, with a first material forming a perimeter of a bore in the die plate and a second material forming an outer portion of the die plate. 
     
     
         17 . The die assembly of  claim 16 , wherein at least one of the first and second materials is a ceramic material, a steel, or a consumable material. 
     
     
         18 . The die assembly of  claim 1 , wherein a front face of the die body near the entrance is configured to mate with a centering insert having a diameter substantially equal to the diameter of the entrance. 
     
     
         19 . The die assembly of  claim 18 , wherein the centering insert and a perimeter of the entrance are formed from the same material. 
     
     
         20 . The die assembly of  claim 1 , wherein the die body is configured to receive a mandrel tip through the entrance such that the mandrel tip is positionable within the interior passage of the die body. 
     
     
         21 . The die assembly of  claim 20 , wherein the interior surface of the die body comprises a complementary portion having an angle that corresponds to an angle of an outer surface of the mandrel tip. 
     
     
         22 . The die assembly of  claim 20 , wherein the die body is configured to receive a billet pressed through the interior passage of the die body to form an extruded product, the extruded product having an outer diameter corresponding to the diameter of the exit of the die body and an inner diameter corresponding to a diameter of the mandrel tip. 
     
     
         23 - 44 . (canceled)