초록 ▼

A die and a die assembly are disclosed for use in association with an underwater pelletizer. The die has unique coiled heating elements which allow for uniform heating of the extrusion orifices which pass through the die, reducing or eliminating polymer solidification within the die, thereby allowin

A die and a die assembly are disclosed for use in association with an underwater pelletizer. The die has unique coiled heating elements which allow for uniform heating of the extrusion orifices which pass through the die, reducing or eliminating polymer solidification within the die, thereby allowing the manufacture of uniform pellets of a specific geometry. The heating elements are contained within the die plate of the die, and in a preferred embodiment occupy annular grooves formed therein which are concentric with the extrusion orifice pattern. The die assembly includes thermally-insulating adaptors and gaskets which cover the annular grooves containing the heating elements.

대표청구항 ▼

1. An extrusion die assembly for use in an underwater pelletizer having an extruder and a water chamber, said die assembly comprising:a) a die plate having an upstream extruder face and a downstream cutting face; b) an inner annular groove formed in one face of said die plate; c) an outer annular gr

1. An extrusion die assembly for use in an underwater pelletizer having an extruder and a water chamber, said die assembly comprising:a) a die plate having an upstream extruder face and a downstream cutting face; b) an inner annular groove formed in one face of said die plate; c) an outer annular groove formed in one face of said die plate; d) a plurality of spaced-apart extrusion orifices extending through said die plate from said extruder face to said cutting face, said orifices arranged in a pattern occupying a space between said inner and outer annular grooves; e) a coiled heating element conned within each of said inner and outer annular grooves, said coiled hearing elements having leads extending outwardly from said die plate for connection to an electrical source; and f) a die cone attached to the central portion of said extruder face of said die plate, said die cone covering and enclosing said inner annular groove but not said extrusion orifices.