Abstract: A device for producing pre-stretch film includes a die defining a die outlet through which molten polymer is extruded. The polymer is suitable for producing the pre-stretch film. A film producing device is spaced apart from the die. One or more coolant supplies are positioned proximate the film producing device for directing a stream of coolant onto the molten polymer positioned on the film producing device.

Abstract: A heater-cooler system for a barrel of an extruder is disclosed. The system includes a heater adapted to be in thermal communication with at least a portion of a barrel of an extruder. The system further includes a shroud assembly that defines a cavity. The shroud assembly encloses the heater. The shroud assembly has an intake port and an exhaust port. A valve is in fluid communication with the exhaust port. The valve is moveable between an open position and a closed position. When the valve is in the closed position the exhaust port is substantially sealed. When the valve is moved between the closed position and the open position or is in the open position the cavity is in fluid communication an area outside of the cavity through the exhaust port.

Abstract: An axially elongated extruder screw includes a screw body having an axially extending extruding portion defined by a feed section at an inlet end of the screw, a metering section at an outlet end of the screw and a barrier section between the feed and metering sections. At least one helical primary flight extends about and is coaxial with the screw body. The primary flight and the screw body cooperate to form a channel in the feed section for conveying resinous material to the barrier section. The barrier section includes at least one helical secondary flight extending from the primary flight about the screw body which in turn defines a first surface of revolution between the primary and secondary flights. At least one helical tertiary flight is positioned between the primary and secondary flights and also extends about the screw body which defines a second helical surface of revolution between the secondary and tertiary flights.

Abstract: An axially elongated extruder screw includes a screw body having an axially extending extruding portion defined by a feed section at an inlet end of the screw, a metering section at an outlet end of the screw and a barrier section between the feed and metering sections. At least one helical primary flight extends about and is coaxial with the screw body. The primary flight and the screw body cooperate to form a channel in the feed section for conveying resinous material to the barrier section. The barrier section includes at least one helical secondary flight extending from the primary flight about the screw body which in turn defines a first surface of revolution between the primary and secondary flights. At least one helical tertiary flight is positioned between the primary and secondary flights and also extends about the screw body which defines a second helical surface of revolution between the secondary and tertiary flights.

Abstract: An axially elongated extruder screw includes a screw body having an axially extending extruding portion defined by a feed section at an inlet end of the screw, a metering section at an outlet end of the screw and a barrier section between the feed and metering sections. A first helical primary flight extends continuously about and is coaxial with the screw body substantially along the entire length of the extruder screw. A second helical primary flight extends continuously at least part-way along the feed section to the outlet end of the extruder screw. The barrier section of the extruder screw defines first and second barrier flights positioned between the primary flights and cooperating therewith to form first and second melt and solids channels that extend along the barrier section of the extruder screw.