A sizer for cooling an extrudate, which includes a core and a housing. The core includes an extrusion channel which accommodates the extrudate, a core cooling channel, and a core vacuum channel in fluid communication with the extrusion channel. The housing includes a housing cooling channel and a housing vacuum channel. The core cooling channel is in fluid communication with the housing cooling channel, and the core vacuum channel is in fluid communication with the housing vacuum channel.

The present invention relates to a novel die assembly for the melt extrusion of ultra-high molecular weight polyethylene (UHMWPE) comprising a tapered channel section, and a process for pelletising UHWMPE using such die assembly. Using the die assembly according to the invention, UHMWPE pellets having improved mechanical properties such as tensile strength, improved density, and reduced oxidation index can be obtained.

The present invention relates to a novel die assembly for the melt extrusion of ultra-high molecular weight polyethylene (UHMWPE) comprising a tapered channel section, and a process for pelletising UHWMPE using such die assembly. Using the die assembly according to the invention, UHMWPE pellets having improved mechanical properties such as tensile strength, improved density, and reduced oxidation index can be obtained.

A method of using a print head assembly, in extrusion-based additive construction is disclosed. The print head may be optionally equipped with a fluid channel for aiding in the regulation of the temperature of the print head cold end, and one or more thermal monitors for monitoring the temperature of the cold end of the print head.

A system for optimizing the multi-extruder deposition process in a 3D printer including multiple extruders requires each extruder to have a body including an outer thermal insulation shell; the shell allowing the inlet/outlet of a fluid for the active and controlled refrigeration of the extruder. A method for optimizing the multi-extruder deposition process in a 3D printer with multiple extruders involves managing the temperature of each extruder using active refrigeration sized so as to have a sudden control of the cooling ramp and to manage the viscosity of the material in the event of extruder change. For the entire duration of the printing with another extruder, the unused extruder nozzle remains in a limited range around the extrusion temperature, thus eliminating downtime, while the solidified filament from the sudden forced cooling is pulled back into a low temperature nozzle area where it does not degrade during non-use.

A system for optimizing the multi-extruder deposition process in a 3D printer including multiple extruders requires each extruder to have a body including an outer thermal insulation shell; the shell allowing the inlet/outlet of a fluid for the active and controlled refrigeration of the extruder. A method for optimizing the multi-extruder deposition process in a 3D printer with multiple extruders involves managing the temperature of each extruder using active refrigeration sized so as to have a sudden control of the cooling ramp and to manage the viscosity of the material in the event of extruder change. For the entire duration of the printing with another extruder, the unused extruder nozzle remains in a limited range around the extrusion temperature, thus eliminating downtime, while the solidified filament from the sudden forced cooling is pulled back into a low temperature nozzle area where it does not degrade during non-use.

A nozzle module and a three-dimensional printer are provided. The nozzle module includes a heat dissipation assembly, a locking assembly, and a nozzle assembly. The rotary member can rotate relative to the clamping ring, and a width of the opening is selectively reduced or increased when the rotary member rotates relative to the clamping ring, thereby enabling the clamping ring to clamp or release the nozzle assembly. Quick assembly and quick disassembly can be achieved, the assembly and the disassembly are convenient, and the assembly efficiency and the disassembly efficiency are improved.

A nozzle module and a three-dimensional printer are provided. The nozzle module includes a heat dissipation assembly, a locking assembly, and a nozzle assembly. The rotary member can rotate relative to the clamping ring, and a width of the opening is selectively reduced or increased when the rotary member rotates relative to the clamping ring, thereby enabling the clamping ring to clamp or release the nozzle assembly. Quick assembly and quick disassembly can be achieved, the assembly and the disassembly are convenient, and the assembly efficiency and the disassembly efficiency are improved.