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A pelletizing die includes a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto. The die member has a plurality of polymer channels and a plurality of extrusion orifices connected to a respective one of the channels to form a e

A pelletizing die includes a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto. The die member has a plurality of polymer channels and a plurality of extrusion orifices connected to a respective one of the channels to form a extrusion orifice section. A heating medium system has additional heating medium conduits between channels and a supply and intermediate header for heating the channels (radially from each side) and providing once in and once out heating medium flow. The die member may be formed by high temperature brazing of components using coordinated solder (Ni based or gold-nickel) and component heat treatment temperature. A thin hard face coating may be provided on raised extrusion orifice ring faces around each extrusion orifice section.

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1. A pelletizing die, comprising:a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto, the pelletizing die member comprising:a plurality of polymer channels;a plurality of extrusion orifices, each of said extrusion orifices bei

1. A pelletizing die, comprising:a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto, the pelletizing die member comprising:a plurality of polymer channels;a plurality of extrusion orifices, each of said extrusion orifices being connected to a respective one of said polymer channels to form an extrusion orifice section;heating medium conduits, each heating medium conduit connected to an undivided circumferential header including an inlet and an outlet forming a heating medium system, said heating medium conduits including at least one conduit adjacent to each polymer channel and at least one transition zone conduit between adjacent channels and adjacent to the transition zone of each of said extrusion orifices for uniformly heating polymer in each extrusion orifice, and for heating the polymer channel through a sufficiently large even pressure drop supplied by said undivided circumferential header; anda closed thermal stabilization cavity adjacent to each extrusion orifice in an associated one of said extrusion orifice sections, said thermal stabilization cavity defining a thermal stabilization zone between said die exit side exposed to cooling fluid and said heating medium conduits capable of allowing the polymer to remain in a liquid state up to solidification just as the polymer exits the extrusion orifice.2. A pelletizing die according to claim 1, wherein said thermal stabilization cavity includes a space surrounding each extrusion orifice section at a location inwardly of said die exit side capable of providing thermal stabilization from the cooling effects of the cooling fluid.3. A pelletizing die according to claim 1, wherein said thermal stabilization cavity includes a space extending between each extrusion orifice section at a location inwardly of said die exit side capable of providing thermal stabilization from the cooling effects of the cooling fluid.4. A pelletizing die according to claim 1, wherein said thermal stabilization cavity includes a space extending substantially circumferentially between each extrusion orifice section at a location inwardly of said die exit side capable of providing thermal stabilization from the cooling effects of the cooling fluid.5. A pelletizing die according to claim 1, wherein said thermal stabilization cavity includes a space extending substantially radially between each extrusion orifice within each extrusion orifice section at a location inwardly of said die exit side capable of providing thermal stabilization from the cooling effects of the cooling fluid.6. A pelletizing die according to claim 1, wherein said thermal stabilization cavity is filled with a heat transfer media that provides good heat transfer characteristics.7. A pelletizing die according to claim 1, wherein said thermal stabilization cavity transports heat through a convective, radiative and conductive medium.8. A pelletizing die comprising:a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto, the pelletizing die member comprising:a plurality of polymer channels;a plurality of extrusion orifices connected to a respective one of said polymer channels to form an extrusion orifice section;heating medium conduits forming a heating medium system, said heating medium conduits including at least one conduit adjacent to each polymer channel for heating the polymer channel;a polymer channel to extrusion orifice transition zone defining means for preventing melt-fracture including a polymer channel connected to each of said extrusion orifices having a geometry based on specific polymer characteristics with related optimal pressures, and flow rates that eliminate melt fracture of the particular polymer and having said polymer characteristics with thermal transition of the polymer for optimal pellet quality; anda thermal stabilizing cavity adjacent to each of said extrusion orifices in an associated said extrusion orifice section, said thermal stabilization cavity defining a thermal stabilization zone between said die exit side exposed to cooling fluid and said heating medium conduits capable of allowing the polymer to remain in a liquid state up to solidification just as the polymer exits the extrusion orifice.9. A pelletizing die comprising:a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto, the pelletizing die member further comprising:a plurality of polymer channels;a plurality of extrusion orifices connected to a respective one of said polymer channels at an extrusion orifice transition zone to form an extrusion orifice section;a heating medium system with an undivided circumferential header including an inlet and an outlet, said undivided circumferential header capable of feeding a heating medium conduit through a sufficiently large even pressure drop adjacent to each polymer channel for uniformly heating the polymer channel including a transition zone conduit between adjacent channels and adjacent to the transition zone of each of said extrusion orifices for uniformly heating polymer in each extrusion orifice; anda thermal stabilization cavity adjacent to each extrusion orifice in an associated said extrusion orifice section, said thermal stabilization cavity defining a thermal stabilization zone between said die exit side exposed to cooling fluid and said heating medium conduits capable of allowing the polymer to remain in a liquid state up to solidification just as the polymer exits the extrusion orifice.10. A pelletizing die according to claim 9, wherein said heating medium system includes a heating medium conduit radially outwardly of each extrusion orifice section and adjacent to each of said channels with said transition zone conduits surrounding each of said transition zones.11. A pelletizing die according to claim 9, wherein said heating medium system includes a heating medium conduit radially inwardly of each extrusion orifice section and adjacent to each of said channels.12. A pelletizing die according to claim 9, wherein said heating medium system includes another heating medium conduit between adjacent channels.13. A pelletizing die according to claim 9, wherein said heating medium system includes a supply heating medium conduit radially outwardly of each extrusion orifice section and adjacent to each of said channels, said supply heating medium conduit being connected to said transition zone conduits for supplying heating medium to said transition zone conduits, additional heating medium conduits between adjacent channels and an intermediate heating medium conduit radially inwardly of each extrusion orifice section and adjacent to each of said channels, said intermediate heating medium conduit being connected to said transition zone conduits and being connected to said additional heating medium conduits for transferring heating medium between said transition zone conduits and said additional heating medium conduits for even heat distribution to the polymer based on once in and once out heating medium flow.14. A pelletizing die according to claim 13, wherein said supply conduit is an inlet header extending circumferentially about said polymer channels capable of providing essentially equal pressure and flow to the entry of each of said transition zone channels and with a discharge header extending circumferentially about said polymer channels and connected to each of said additional channels, said discharge header having a geometry capable of providing equal flow and pressure drop across each of said additional channels.15. A pelletizing die, comprising a pelletizing die member with a die exit side exposed to cooling fluid and a die entry side for receiving polymer fed thereto, the pelletizing die member comprising:a plurality of polymer channels;a plurality of extrusion orifices connected to a respective one of said polymer channels at a transition zone to form an extrusion orifice section;heating medium conduits forming a heating medium system, said heating medium conduits including at least one conduit adjacent to each polymer channel for heating the polymer channel and at least one transition zone conduit adjacent to said transition zone; andat least a thermal stabilization cavity defined by a continuous closed surface, said cavity being adjacent to each extrusion orifice and adjacent to said die exit side in an associated one of said extrusion orifice sections, said thermal stabilization cavity defining a thermal stabilization zone between said die exit side exposed to cooling fluid and said heating medium conduits capable of allowing the polymer to remain in a liquid state up to solidification just as the polymer exits the extrusion orifice.16. A pelletizing die according to claim 15, wherein said thermal stabilization cavity includes at least one of a circular geometric space surrounding said plurality of extrusion orifice sections, a longitudinal geometric space alongside said plurality of orifice sections, and an interval-filling geometric space between each of said plurality of orifice sections, at a location inwardly of said die exit side capable of providing thermal stabilization from the cooling effects of the cooling fluid.17. A pelletizing die according to claim 15, wherein said thermal stabilization cavity transmits heat through a convective, radiative and conductive medium.