Modular extrusion die tools

Abstract

Modular extrusion die tools for extruding an extrudable material into an extruded article. In at least some embodiments, an extrusion die tool comprises a base, a sizing plate, a mandrel, and a die holder. When the sizing plate and mandrel are removably inserted into the base, and the base is removably inserted into the die holder, a billet of extrudable material may be injected under high pressure into the die tool. As it exits the die tool, the material is extruded into a desired shape. Because of the extreme forces to which the extrusion die tools are repeatedly subjected, some portions of the die tools can wear out relatively rapidly. Other portions, however, wear at a much slower pace. Consequently, certain portions of the die tool may need to be replaced more frequently than other portions. Because the extrusion die tools of the present invention are modular, the highly-worn portions of a die tool may be replaced without replacing the entire tool.

1 . A modular extrusion die tool for use in extruding a material forced therethrough into an extruded article, comprising:
 a base comprising an opening formed along a transverse axis from a first side of the base to a second side of said base, the opening defining an internal surface within the base;   a sizing plate holder formed on the first side of the base along an edge of the opening;   a bridge joined to the base on the second side of the base and spanning the opening, the bridge having a receiving slot formed through the bridge from a first surface of said bridge that faces away from the base to a second surface of the bridge that faces inwardly toward the opening, and the receiving slot being essentially aligned with the transverse axis;   a sizing plate having an extrusion slot formed therethrough, the sizing plate configured to be removably inserted into the sizing plate holder and retained therein over the opening in the base so that the extrusion slot substantially aligns with the receiving slot;   a mandrel having a distal end and a proximal end, the mandrel adapted for insertion into the receiving slot such that the distal end extends beyond the second surface and is positioned adjacent to the extrusion slot to form an extrusion gap between the distal end and an edge of said extrusion slot; and   a die holder having a first end, a second end and an interior extending therebetween, the interior comprising at least one die chamber positioned adjacent to the second end of the die holder and configured to removably receive and retain the base therein, and the first end of the die holder comprising an inlet port in communication with the die chamber.   
   
   
       2 . The die tool of  claim 1 , wherein the inlet port defines an inlet port wall within the die holder. 
   
   
       3 . The die tool of  claim 2 , wherein the inlet port wall is tapered from the first end of the die tool to the opening in the base such that the inlet port is funneled down to the approximate size of the opening in the first side of said base. 
   
   
       4 . The die tool of  claim 2 , wherein the inlet port wall forms an angle of between about 135° and about 90° with the second side of the base. 
   
   
       5 . The die tool of  claim 2 , wherein the internal surface of the opening in the base is tapered to funnel down the opening from the second side of the base to the first side of the base. 
   
   
       6 . The die tool of  claim 1 , further comprising a splitter plate adapted to be removably coupled to the bridge such that the splitter plate covers the proximal end of the mandrel when the mandrel is fully inserted into the receiving slot. 
   
   
       7 . The die tool of  claim 1 , wherein the die holder further comprises a splitter plate mounted to the die holder in the inlet port such that the splitter plate covers the proximal end of the mandrel when the mandrel is inserted into the receiving slot and the base is inserted into the die chamber in the die holder. 
   
   
       8 . The die tool of  claim 6 , wherein the first end of the die holder comprises an exterior surface positioned along a plane and when the splitter plate is removably coupled to the bridge, the splitter plate is recessed within the inlet port such that the splitter plate does not meet the plane of the exterior surface of the die holder. 
   
   
       9 . The die tool of  claim 7 , wherein the first end of the die holder comprises an exterior surface positioned along a plane and the splitter plate is recessed within the inlet port such that the splitter plate does not meet the plane of the exterior surface of the die holder. 
   
   
       10 . The die tool of  claim 6 , wherein the splitter plate comprises a rounded configuration. 
   
   
       11 . The die tool of  claim 7 , wherein the splitter plate comprises a rounded configuration. 
   
   
       12 . The die tool of  claim 7 , wherein the mandrel is shaped to fit within the receiving slot such that the proximal end of the mandrel is flush with the first surface of the bridge. 
   
   
       13 . The die tool of  claim 7 , wherein the mandrel has a transverse axis, a longitudinal axis perpendicular to the transverse axis, and a cross axis perpendicular to both the longitudinal axis and the transverse axis, and the distal end of the mandrel has at least one tooth formed thereon, the at least one tooth having at least two undercut surfaces aligned perpendicularly to the longitudinal axis and the transverse axis of the mandrel. 
   
   
       14 . The die tool of  claim 1 , wherein:
 the bridge has a recess formed on the first surface around the periphery of the receiving slot; and   the mandrel has a mandrel base formed on the proximal end of the mandrel, the mandrel base adapted to fit within the recess so that the mandrel base is flush with the first surface of said bridge when the mandrel is inserted into the receiving slot.   
   
   
       15 . The die tool of  claim 10 , wherein:
 the splitter plate has two ends, each end having a leg projecting transversely to the splitter plate; and   the bridge has two ends, each end having a notch configured so that the legs of the splitter plate fits into the notches of the bridge to removably join the splitter plate to the bridge.   
   
   
       16 . The die tool of  claim 7 , wherein:
 the base has an external surface between the first side and the second side and the external surface is tapered; and   the die chamber in the die holder has a tapered internal surface that mates with the tapered external surface of the base so that the base can be removably inserted into the die chamber.   
   
   
       17 . A modular extrusion die tool for use in extruding a material forced therethrough into an extruded article, comprising:
 a base comprising an opening formed along a transverse axis from a first side of the base to a second side of said base, the opening defining an internal surface within the base;   a sizing plate holder formed on the first side of the base along an edge of the opening;   a bridge joined to the base on the second side of the base and spanning the opening, the bridge having a receiving slot formed through the bridge from a first surface of said bridge that faces away from the base to a second surface of the bridge that faces inwardly toward the opening, and the receiving slot being essentially aligned with the transverse axis;   a sizing plate having an extrusion slot formed therethrough, the sizing plate configured to be removably inserted into the sizing plate holder and retained therein over the opening in the base so that the extrusion slot substantially aligns with the receiving slot;   a mandrel having a distal end and a proximal end, the mandrel adapted for insertion into the receiving slot such that the distal end extends beyond the second surface and is positioned adjacent to the extrusion slot to form an extrusion gap between the distal end and an edge of said extrusion slot; and   a die holder having a first end, a second end, an interior extending therebetween and a splitter plate, the interior comprising at least one die chamber positioned adjacent to the second end of the die holder and configured to removably receive and retain the base therein, the first end of the die holder comprising an inlet port in communication with the die chamber, and the splitter plate mounted to the die holder in the inlet port such that the splitter plate covers the proximal end of the mandrel when the mandrel is inserted into the receiving slot and the base is inserted into the at least one die chamber of the die holder.   
   
   
       18 . The die tool of  claim 17 , wherein the first end of the die holder comprises an exterior surface positioned along a plane and the splitter plate positioned within the inlet port such that when the splitter plate is removably coupled to the bridge, the splitter plate does not meet the plane of the exterior surface of the die holder. 
   
   
       19 . The die tool of  claim 17 , wherein the splitting plate comprises a rounded configuration. 
   
   
       20 . The die tool of  claim 17 , wherein the die holder has a plurality of die chambers. 
   
   
       21 . The die tool of  claim 17 , wherein at least one portion of the modular extrusion die tool is formed from an annealed high-speed steel having a chemical composition comprising one or more of: Manganese, Silicon, Chromium, Vanadium, Tungsten, Molybdenum, Cobalt, and Sulfur. 
   
   
       22 . The die tool of claim  24 , wherein at least one portion of the modular extrusion die tool is formed from a hot-working steel having a chemical composition comprising one or more of: Manganese, Silicon, Chromium, Vanadium, and Molybdenum.