A conveyance portion, a barrier portion, and a path are provided at places of a portion of a screw main body in which a kneading portion is provided. In at least one of the places, an entrance is opened to cause raw materials, conveyance of which is limited by a barrier portion to increase pressure on the raw materials, to flow in. The raw materials flowing in from the entrance flow through the path in the opposite direction to a conveyance direction of the conveyance portion. An exit is opened in an outer circumferential surface of the screw main body at a position outside the conveyance portion in which the entrance is opened.

An extruder or other similar tool head of a three-dimensional printer is slidably mounted along a feedpath of build material so that the extruder can move into and out of contact with a build surface according to whether build material is being extruded. The extruder may be spring-biased against the forward feedpath so that the extruder remains above the build surface in the absence of applied forces, and then moves downward into a position for extrusion when build material is fed into the extruder. In another aspect, modular tool heads are disclosed that can be automatically coupled to and removed from the three-dimensional printer by a suitable robotics system. A tool crib may be provided to store multiple tool heads while not in use.

The present invention relates to a process for producing transparent polymeric films or plastics moldings of particularly high chemical resistance, having more particularly a very good resistance towards oil-in-water and water-in-oil emulsions, and of high optical quality.

A single-screw extrusion desulfurization and post-processing system and a method for preparing reclaimed rubber. The single-screw extrusion desulfurization and post-processing system comprises: a single-screw desulfurization device, a single-screw post-processing device and a closed connection device for connecting the single-screw desulfurization device and the single-screw post-processing device, the single-screw post-processing device includes a post-processing feeding unit and a post-processing unit which are connected with each other, and a post-processing screw running through the post-processing feeding unit and the post-processing unit.

A biomass-derived thermosetting polymer material being a product of processing a biomass feed material via a twin screw extruder having a length extending between an inlet and an outlet. Hot water from a water heater is injected into at least one inlet along the length of the twin screw extruder, the at least one inlet generally corresponding with a pressure boundary within the twin screw extruder. A pressure-sustaining valve is connected between the length of the twin screw extruder and the outlet, with the valve being adjusted to produce the biomass-derived thermosetting polymer material.

A system for depositing a composite filler material into a channel of a composite structure includes an end-effector configured to extrude a bead of the filler material into the channel. The filler material can comprise a first group of relatively long fibers, a second group of relatively short fibers and a resin. A drive system is configured to move the end-effector relative to the channel, and a position sensor is configured to detect the position of the bead relative to the channel. A controller is configured to operate the drive system in response to the detected position and to operate the end-effector to heat and compress the filler material so as to orient the longer fibers in a substantially longitudinal direction relative to the channel and the shorter fibers in substantially random directions relative to the channel when the bead is extruded into the channel.

Multi-filament UHMW PE yarns can be produced according to processes that result in improved properties. The UHMW PE can have an intrinsic viscosity in decalin at 135 C. of at least about 30 dl/g, and can be processed under optimal conditions to achieve a gel spun yarn having a tenacity of greater than about 45 g/d (40.5 g/dtex).

An extruder for processing hydrocarbon-containing material. The extruder includes a screw that is rotatably positioned in a auger barrel and a heating system positioned about at least a portion of the auger barrel that is designed to heat the hydrocarbon-containing material as the hydrocarbon-containing material moves through the auger barrel.

Multi-material, three-dimensional fabrication is improved by the use of a purge wall adjacent to an object to absorb transitional artifacts of material changes. The structure of the purge wall may be selected to reduce build time, and to reduce certain printing artifacts such as warping and delaminating. For example, alternating layers of offset or mirrored zigzag patterns may be used to reduce and distribute the layer-to-layer adhesion surfaces throughout the purge wall while providing sufficient contact points to maintain the structural integrity of the purge wall.

The extrusion of polymer compositions based on polyvinyl chloride (PVC) and in particular to a method in which polymer compositions are produced that have an elongation at break of at least 200%, a tensile strength of at least 10 N/mm2 with a specific energy input SEI of 0.03 to 0.20 kWh/kg and in particular 0.04 to 0.16 kWh/kg. The method is expediently carried out such that a plasticiser is added in a plurality of portions to the non-composed polyvinyl chloride and mixed into said polyvinyl chloride. The method thereby offers a fast and simple possibility of producing products from finished soft PVC, the production of said products requiring only a single processing device in the form of an extruder.