An apparatus for use in 3D fabrication includes a heat sink, a melt tube extending through the heat sink, the melt tube having a first end and an opposite second end and adapted for melting filament or other material as the material is conveyed from the first end to the second end, a pen tip having an opening therein for ejecting melted material, the pen tip at the second end of the melt tube, and a pen tip holder for securely holding the pen tip during printing, the pen tip holder having a heater element associated therewith.

Extruder feed system. The system includes a pair of spaced-apart, internally and oppositely threaded rotatable elements for receiving and engaging a plastic filament material. An electric motor rotates the rotatable elements in opposite directions thereby to drive the filament into a liquefier chamber for subsequent discharge through a nozzle. The system provides very accurate layer-by-layer build up.

Disclosed are plastic products from a recycled plastic mix of unidentified, unclean and unsorted mixed plastic waste made with a system comprising thermal and mechanical processing of the recycled plastic waste using continuous extrusion foaming, two-phase cooling, continuous metering of the pulling strength and automatic adjustment of the pulling speed and extrusion speed.

High strength biomedical materials and processes for making the same are disclosed. Included in the disclosure are nanoporous hydrophilic solids that can be extruded with a high aspect ratio to make high strength medical catheters and other devices with lubricious and biocompatible surfaces.

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 method and system are disclosed. A method of printing onto a base having an upper surface spaced from a lower surface by a base thickness includes dispensing a yarn from a nozzle of a printing system and selectively attaching the yarn to a first attachment region. The step of dispensing the yarn includes dispensing a heat-moldable material and a melt-resistant material. The step of selectively attaching the yarn to the first attachment region includes moving the nozzle into the first attachment region. The step of moving the nozzle into the first attachment region reduces the base thickness by a prodding distance. The heat-moldable material bonds to the first attachment region.

A device (4) for the manufacture of an annular extrudate comprises a jacket (2), a crosshead (1) arranged inside of the jacket. The jacket contains a melt passage, whereby the crosshead is arranged in the melt passage, such that the melt passage extends et least at the outlet of the device as an annular melt passage around the crosshead (1). An annular passage (5) is formed between the crosshead and the jacket. The annular passage contains a static mixer (3), whereby the crosshead is at least partially supported by the static mixer in the jacket. The static mixer comprises a plurality of inserts, whereby at least a portion of the inserts is connected to the crosshead and/or the jacket.

High strength biomedical materials and processes for making the same are disclosed. Included in the disclosure are nanoporous hydrophilic solids that can be extruded with a high aspect ratio to make high strength medical catheters and other devices with lubricious and biocompatible surfaces.

A composition and a manufacturing method of a highly flame-retardant and low-smoke extruded polyvinyl chloride pipe are provided. The composition includes a polyvinyl chloride resin material, a flame retardant additive and a carbon forming additive. The polyvinyl chloride resin material is in an amount between 10 PHR (parts per hundred resin) and 90 PHR. The flame retardant additive is in an amount between 0.5 PHR and 2.0 PHR, and is a phosphorus-containing flame retardant modified by a modifier. The carbon forming additive is in an amount between 0.2 PHR and 1.0 PHR. The carbon forming additive is at least one material selected from a group consisting of zinc chloride, zinc stearate, calcium stearate, zinc hydroxystannate, anhydrous zinc stannate, zinc phosphate and zirconium phosphate. A total added amount of the flame retardant additive and the carbon forming additive in the composition is not greater than 3 PHR.

An article may include a carcass or jacket, and at least one composite member arranged within the carcass or jacket for inhibiting longitudinal stretch of the article. The composite member may include a plurality of fibers arranged in a polymeric binder, the polymeric binder bonding the composite member to the carcass or jacket. The carcass or jacket may be formed substantially of rubber or thermoplastic elastomer. The plurality of fibers may include fibers formed substantially from at least one of S-glass, aramid and carbon fiber. The polymer binder may be formed substantially of a thermoplastic material or of a thermoset material. In manufacturing of the article, the carcass or jacket may be extruded to surround the composite member. The article may be a handrail or an elevator belt.