A print head for a filament 3D printer includes a channel for guiding a polymer filament through an outlet opening, a heating block in contact with the outlet opening of the channel and configured to heat the polymer filament, a nozzle having an outlet aperture, where the nozzle is connected to the outlet opening of the channel so that the polymer filament passes through the outlet aperture, and the outlet aperture of the nozzle is arranged axisymmetrically around the nozzle and located on a longitudinal axis (T) of the nozzle, and one or more air outlet openings directed towards a meeting zone (P) defined by tips of the air outlet openings and the outlet aperture of the nozzle.

Silicone-containing light fixture optics. A method for manufacturing an optical component including an inner optical component and an outer optical component. The method may include providing a first optical component; providing a material that comprises silicone; moving the material through an extrusion die to form a second optical component on the first optical component to form a continuous length of extruded optic. The first optical component can be one of the inner optical component or the outer optical component, and the second optical component can be the other of the inner optical component or the outer optical component and different from the first optical component. The method may further include curing the continuous length of extruded optic; and cutting the continuous length of extruded optic at a desired length to form the linear optic.

A print head for a 3D printer includes a nozzle for dispensing molten material. A pipe is connected to the nozzle and carrying a heating resistor layer. The pipe is seated in an annular bracket. Spring contacts are mounted on the bracket, which contacts bear against the pipe at mutually opposite points and contact the heating resistor layer.

An extrusion head arrangement has a plurality of extrusion heads arranged next to one another along a transverse axis. Each extrusion head has a housing with at least one flow channel for forming a strand of extrudable plastic in the direction of a longitudinal axis. The housing has an outer housing part extending along the longitudinal axis with an outer circumferential surface. A longitudinal bore parallel to the longitudinal axis is arranged in the outer housing part. The outer circumferential surface of the outer housing part has an oval cross-section with a largest diameter and a smallest diameter. The extrusion heads are arranged next to each other with the smallest diameters parallel to the transverse axis. The longitudinal bores are each arranged on a diameter deviating from the smallest diameter.

The present invention relates to a method for continuously manufacturing UHMWPE products comprising:providing a counter-rotating twin-screw extruder;feeding UHMWPE powder into a hopper of said counter-rotating twin-screw extruder;transporting said UHMWPE powder from said hopper through said counter-rotating twin-screw extruder to an outlet of said counter-rotating twin-screw extruder;further transporting said UHMWPE powder from said outlet of said counter-rotating twin-screw extruder to an entrance of a heat-controlled tooling system for defining the shape of UHMWPE products;withdrawing said UHMWPE products from an outlet of said heat-controlled tooling system.

Provided is a tube comprising a tetrafluoroethylene/fluoroalkyl vinyl ether copolymer, wherein the tube inner surface has a surface roughness Ra of 5 nm or less measured by atomic force microscopy (AFM) with an evaluation length set to 3 m, and the tube has an amount of metals eluted from the tube inner surface of 0.30 ng/cm.sup.2 or less.

A production device for melt-blown non-woven fabric, with which a high molecular weight polymer can be reduced in molecular weight by applying a shear force to the high molecular weight polymer without adding an additive such as a peroxide that promotes thermal decomposition reaction, and a low molecular weight polymer can be efficiently produced. The low molecular weight polymer and the melt-blown non-woven fabric are produced using a continuous high shearing device that applies a shear force to the high molecular weight polymer serving as a raw material by rotation of a screw body 37 to reduce the molecular weight of the high molecular weight polymer so as to obtain a low molecular weight polymer, and cools the low molecular weight polymer by passing the low molecular weight polymer through a passage 88 arranged in the axial direction inside the screw body 37.

A 3D printing system includes a first cartridge container for reversibly receiving a first cartridge which stores printing fluid for 3D printing, and a print head with an outflow opening. The 3D printing system further has a first fluid line, which connects the first cartridge container to the print head to supply printing fluid to the print head. In addition, the 3D printing system has a first temperature-control channel, which encases the first cartridge container and the first fluid line externally, and which is passed through, in the intended state of use, by a temperature-control medium.

A heat bolt unit according to one embodiment includes a plurality of heat bolts disposed in parallel to one another, and a holding portion that holds the plurality of heat bolts. The holding portion holds a base end portion of each of the plurality of heat bolts disposed in parallel to one another. In other words, the holding portion holds the plurality of heat bolts disposed in parallel to one another in a cantilever manner.

An illustrative example embodiment of a method of making a concrete expansion joint insert includes moving a material including a resin having a melt temperature through a die having a flow passage that ends in an exit having a selected geometry, increasing a temperature of only a segment of the die near the exit to an elevated temperature that is at least 1.5 times the melt temperature, and increasing the temperature of a portion of the material to an increased temperature above the melt temperature through contact with the segment having the elevated temperature.