Disclosed herein are three-dimensional porous tubular scaffolds for cardiovascular, periphery vascular, nerve conduit, intestines, bile conduct, urinary tract, and bone repair/reconstruction applications, and methods and apparatus for making the same.

A molding apparatus, a cigarette filter rod and a preparation method thereof are disclosed. The molding apparatus comprises a single-screw extrusion system and a cooling setting system. The single-screw extrusion system comprises a feeder and an extruder. The feeder is arranged on the extruder. The extruder comprises a cylinder. A heater is arranged outside the cylinder. A screw is arranged inside the cylinder, and a mouth mold is arranged at one end of the cylinder. The cooling setting system comprises a round tube and a cooler. The cooler (6) is arranged outside the round tube. One end of the round tube is butted with the mouth mold of the extruder; and multiple groups of grooves are formed on threads of the head of the screw.

An extruder is disclosed including: a barrel; and a screw provided with a helical groove; wherein the screw comprises a dewatering portion comprising a first portion, and a second portion at a location downstream from the first portion; wherein, at the dewatering portion, clearance between the groove and the barrel decreases as one proceeds downstream; and wherein clearance reduction ratio at the first portion is greater than clearance reduction ratio at the second portion.

An extruder is disclosed including: a barrel; and a screw provided with a helical groove; wherein the screw comprises a dewatering portion comprising a first portion, and a second portion at a location downstream from the first portion; wherein, at the dewatering portion, clearance between the groove and the barrel decreases as one proceeds downstream; and wherein clearance reduction ratio at the first portion is greater than clearance reduction ratio at the second portion.

This concerns a screw pump for the extrusion of plastic materials, which is extremely compact and so it can be inserted in-line in a plastic material filtration system, encapsulating within it a duct parallel to the axis of the screw.

An extruder screw conveying raw materials while kneading them includes a screw main body, conveyance portions, barrier portions, and paths. The conveyance portions convey the raw materials in an axial direction. The paths each include an entrance and an exit. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in the same direction as a conveyance direction of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position outside the conveyance portions in which the entrance is opened.

An extruder screw conveying raw materials while kneading them includes a screw main body, conveyance portions, barrier portions, and paths. The conveyance portions convey the raw materials in an axial direction. The paths each include an entrance and an exit. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in the same direction as a conveyance direction of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position outside the conveyance portions in which the entrance is opened.

A device for influencing the volume flow of extruded plastically deformable material conveyed to an outlet nozzle. A flange arranged between an extrusion unit and an outlet nozzle and is connected to the extrusion unit and the outlet nozzle. A duct from the extrusion unit and the outlet nozzle is incorporated in the flange. A piston is mounted in the flange to be rotatable perpendicular to the longitudinal axis of the duct and is located through the duct. In the piston there is a hole which opens into a bypass duct routed to a bypass nozzle. On the outer lateral surface of the piston there is at least one groove in the region of the duct so that, depending on the angular positions of the piston, material can be conveyed through the at least one groove to the outlet nozzle or through the hole to the bypass nozzle.

Mixing and plasticating machine (100) for continuous conditioning processes, comprising: a housing (10) in which a hollow interior (18) is formed that is delimited by the interior peripheral surface of the housing (10) and extends in the longitudinal direction of the mixing and plasticating machine (100); a screw shaft (12) which extends through the interior (18) of the housing (10), rotates in the interior (18) of the housing (10) during operation and simultaneously moves translationally back and forth; a drive which rotates the screw shaft (12) during operation; and a filling device (36) arranged on the housing (10), for feeding at least one starting material into the interior (18) of the housing (10), the filling device (36) extending through a cut-out (42) that extends through the housing wall (40) or being connected to a cut-out (42) that extends through the housing wall (40), the filling device (36) comprising at least two cavities (54, 54′) that each extend over the height of the filling device (36), which cavities are separated from one another by at least one separating wall (52, 52′).

An improved extruder apparatus is disclosed and which includes a cylindrical barrel having a feed end and a discharge end, the feed end having an inlet in fluid communication with a hopper. The extruder screw is mounted in the cylindrical barrel, and the screw has an outer surface having one or more helical flights mounted thereon, wherein the inlet end of the cylindrical barrel has a support frame mounted thereto, wherein an upper surface of the support frame is connected to a throat of a hopper, wherein an insert is mounted to the support frame and has a lower end which extends down into the cylindrical barrel, wherein the insert has an internal passageway having a first opening on the lower end and a second opening upstream of the screw for relieving the pressure.