Abstract: A flow control device is mounted within a channel of an extrusion die, wherein the channel is defined by a base surface and a side surface normal to the base surface. The device includes a main body and an auxiliary body, wherein the main body includes a side portion that sealingly contacts the side surface of the channel when a force is exerted on the side portion, and the auxiliary body is in contact with the base surface of the channel. The device further includes a flexible membrane on a face opposite the auxiliary body which can influence the flow of material through the channel by moving in a direction perpendicular to the direction of material flow. A sealing apparatus is used to prevent leakage of material between the die and the flexible membrane. The sealing apparatus includes a gasket disposed adjacent an end surface of the membrane and means for causing the gasket to apply a force against the end surface such that the gasket seals against the membrane.

Abstract: A flow control device is mounted within a channel of an extrusion die, wherein the channel is defined by a base surface and a side surface normal to the base surface. The device includes a main body and an auxiliary body, wherein the main body includes a side portion that sealingly contacts the side surface of the channel when a force is exerted on the side portion, and the auxiliary body is in contact with the base surface of the channel. The device further includes a flexible membrane on a face opposite the auxiliary body which can influence the flow of material through the channel by moving in a direction perpendicular to the direction of material flow. A sealing apparatus is used to prevent leakage of material between the die and the flexible membrane. The sealing apparatus includes a gasket disposed adjacent an end surface of the membrane and means for causing the gasket to apply a force against the end surface such that the gasket seals against the membrane.

Abstract: An extrusion apparatus includes first and second die body portions each having a main body and a lip interconnected with the main body wherein the die body portions are joined such that a single die outlet is formed between and bounded by the lips. The apparatus also includes suitable structure for moving the lips to adjust the die outlet.

Abstract: An extrusion apparatus includes first and second die body portions each having a main body and a lip interconnected with the main body wherein the die body portions are joined such that a single die outlet is formed between and bounded by the lips. The apparatus also includes suitable structure for moving the lips to adjust the die outlet.

Abstract: A dual-chamber vacuum box for pinning a thermoplastic web to a cooling roll includes a primary vacuum chamber connected to a first vacuum source. The primary vacuum chamber has a first side located proximate a surface of the web at a line of contact between the web and the cooling roll and a second side opposite the first side. A secondary vacuum is chamber connected to a second vacuum source and is positioned adjacent the second side of the primary vacuum chamber. Apparatus is disposed between the primary and secondary vacuum chambers for creating a pressure variation along the line of contact between the web and the cooling roll.

Abstract: A feed block for coextrusion apparatus includes a main body and a flow distribution module removably located therein. The feed block can be readily disassembled for cleaning and maintenance and the flow distribution module may be readily interchanged with another module without the need to disassemble the feed block or other components attached thereto.