A multi-port single screw extruder combining a heated plastication barrel having a first entrance port and an exit port on opposing ends of the barrel and a second entrance port intermediately positioned therebetween; a first hopper positioned to deliver ingredients to the first entrance port of said barrel; a second hopper positioned to deliver ingredients to the second entrance port and a helical plastication screw rotatably carried within the barrel and running the length thereof between the first entrance port and exit port that is operable to rotate and transmit the ingredients along the length of the barrel; wherein the plastication screw includes a distributive mixing element located between at least one additional entrance port and the exit port, the minor diameter of the plastication screw is reduced in advance of each additional entrance port sufficient to reduce the barrel pressure at each entrance port to a level that permits the addition of ingredients to the barrel through the entrance port, and the ingredients include a thermoplastic polymer.

An extruder screw for plasticizing at least one plastic or plastic mixture, including a melting zone, a shaft zone and a mixing zone arranged between the melting zone and the shaft zone, wherein a conveying flight is formed in the melting zone and in the shaft zone, which extends helically along a longitudinal axis of the screw, wherein a conveying flight of the melting zone ends at an end of the melting zone towards the mixing zone and a conveying flight of the shaft zone begins at an end towards the mixing zone. A flight depth of the melting zone continuously decreases along the longitudinal axis of the screw to the mixing zone. Further, an extrusion device having the extruder screw and to a method for plasticizing at least one plastic or plastic mixture.

A no solid bed extruder screw for processing a material to a molten state has a body with a helical thread formed thereon, the thread having pushing and trailing surfaces. The body has an outer surface and extends longitudinally between feed and discharge ends. A channel for receiving the material to be processed is defined between the outer surface of the body and an outer diameter of the thread bounded by the pushing surface and the trailing surface of the thread. A volume of the channel decreases in a plurality of revolutions of the thread in a direction from the feed end to the discharge end. A channel depth between the pushing surface and the trailing surface decreases for a first portion of the channel toward the feed end and increases for a second portion of the channel toward the discharge end.

A no solid bed extruder screw for processing a material to a molten state has a body with a helical thread formed thereon, the thread having pushing and trailing surfaces. The body has an outer surface and extends longitudinally between feed and discharge ends. A channel for receiving the material to be processed is defined between the outer surface of the body and an outer diameter of the thread bounded by the pushing surface and the trailing surface of the thread. A volume of the channel decreases in a plurality of revolutions of the thread in a direction from the feed end to the discharge end. A channel depth between the pushing surface and the trailing surface decreases for a first portion of the channel toward the feed end and increases for a second portion of the channel toward the discharge end.

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.

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.

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.

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.

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.

Lower discharge temperatures and improved flow rates are obtained for the processing of meltable, solid crosslinkable compositions comprising a polymer, e.g., polyethylene, and a peroxide, in a single barrel extruder by equipping the extruder with an energy transfer (ET) screw that comprises: (1) an ET section with a distance averaged ET section depth of 8.0% to 10% of the extruder barrel internal diameter, and (2) a metering section with a metering section depth of 6.0% to 8% of the extruder barrel internal diameter.