A shearing part for a plasticising screw has at least one inlet channel and at least one outlet channel, which run helically around or parallel to the longitudinal axis (X) of the shearing part. The inlet channel is open upstream and closed downstream. The outlet channel is open downstream and closed upstream. The inlet outlet channels are arranged lying directly adjacent to one another and contiguous to one another, and are connected directly with one another fluidically, so that inflowing melt can flow over directly from the inlet channel into the outlet channel, wherein a flow direction transversely to longitudinal axis (X) of the shearing part is produced. The inlet channel has a depth (T) at which shearing action on the melt is substantially avoided. The outlet channel is configured as shearing surface, so that shearing action is present onto melt flowing through the outlet channel.

A method for producing a foam-molded product by using a plasticizing cylinder, includes: plasticizing and melting the thermoplastic resin to provide the molten resin in a plasticization zone of the plasticizing cylinder; introducing a pressurized fluid containing the physical foaming agent at a fixed pressure into a starvation zone of the plasticizing cylinder to retain the starvation zone at the fixed pressure; allowing the molten resin to be in the starved state in the starvation zone; bringing the molten resin in contact with the pressurized fluid containing the physical foaming agent at the fixed pressure, in the starvation zone in a state in which the starvation zone is retained at the fixed pressure; and molding the molten resin having been brought in contact with the pressurized fluid containing the physical foaming agent into the foam-molded product.

A worm shaft for a mixing and kneading machine particularly for continual processing having a shaft bar, on the circumferential surface of which blade elements are arranged to be spaced apart from one another extending outwards from the circumferential surface of the shaft bar, wherein the blade elements are arranged on the circumferential surface of the shaft bar, at least in one section extending in the axial direction of the worm shaft, in two rows extending in the axial direction of the worm shaft, and wherein each of the blade elements of the at least one section extending in the axial direction of the worm shaft has an elliptic, oval, or biconvex outer peripheral surface in the top view.

An extruder and molding assembly comprising an extruder positioned upstream from a mold, the mold having a mold cavity and a separate pressurization member fluidly connected to the mold cavity wherein the extruder is operable at a first pressure to fill at least a majority of the mold cavity and the pressurization member is operable to fill a remainder of the mold cavity.

A method for producing a foam-molded product by using a plasticizing cylinder, includes: plasticizing and melting the thermoplastic resin to provide the molten resin in a plasticization zone of the plasticizing cylinder; introducing a pressurized fluid containing the physical foaming agent at a fixed pressure into a starvation zone of the plasticizing cylinder to retain the starvation zone at the fixed pressure; allowing the molten resin to be in the starved state in the starvation zone; bringing the molten resin in contact with the pressurized fluid containing the physical foaming agent at the fixed pressure, in the starvation zone in a state in which the starvation zone is retained at the fixed pressure; and molding the molten resin having been brought in contact with the pressurized fluid containing the physical foaming agent into the foam-molded product.

An improved screw has a shaft having a surface and a central axis and at least one flight extending helically along the surface of the shaft in successive turns. A continuous groove is formed in the surface of the shaft and extends between successive, pushing and trailing, turns of the flight at a selected angle greater than zero. The groove defines at least one generally triangular land having a base aligned with a pushing turn of the flight and an apex between successive turns of the flight. The groove also defines another generally triangular land having a base aligned with a trailing turn of the flight. Barriers or dams may be provided on the lands and in the grooves. A second continuous groove may also be formed in the surface of the shaft.

In an injection molding method, using a heating cylinder having on the front end thereof a discharge nozzle, a single axis screw is rotatable inside the heating cylinder, a fiber-supplying device fills reinforcing fiber into the heating cylinder, and injection molding is performed while supplying the reinforcing fiber and the resin starting material separately and supplying the reinforcing fiber on the front side of the resin starting material. The method includes a plasticization process for obtaining a specified amount of a kneaded product by retracting the screw while rotating in the normal direction to melt the resin starting material and knead reinforcing fiber into the melted resin starting material, and an injection process for discharging the kneaded product from the discharge nozzle by advancing the screw. Reinforcing fiber is supplied into the heating cylinder in the injection process.

A screw for a plasticating apparatus has one or more helical flights. A portion of the screw has a plurality of advancing grooves arranged in a noncontinuous helix cut in the screw. The advancing grooves are dimensioned to receive material therein as the material is conveyed through the barrel. The screw has a plurality of noncontinuous cross-cut grooves traversing one or more of the advancing grooves. The cross-cut grooves have a second helix angle greater than the first helix angle and less than ninety degrees; and/or one or more of the cross-cut grooves have a third helix angle of about ninety degrees.

An apparatus for producing a foam-molded product, including a plasticizing cylinder which has a plasticization zone for plasticizing and melting a thermoplastic resin into a molten resin and a starvation zone for allowing the molten resin to be in a starved state and which is formed with an introducing port for introducing a physical foaming agent into the starvation zone; and a physical foaming agent supply mechanism which supplies the physical foaming agent to the plasticizing cylinder via the introducing port, wherein the introducing port is open at all times, and the physical foaming agent having a fixed pressure is continuously introduced into the starvation zone from the physical foaming agent supply mechanism via the introducing port during the producing of the foam-molded product.

A screw includes a screw main body, a conveyance portion conveying a raw material, and a passage provided in the screw main body. The passage includes a first passage element, a second passage element, and a third passage element. The screw main body has a plurality of cylindrical bodies arranged in an axial direction of the rotating shaft. At least a portion of the conveyance portion is formed on outer peripheral surfaces of the cylindrical bodies adjacent to each other, and the passage is formed in the cylindrical body so as to cross over between the adjacent cylindrical bodies.