A method and apparatus for forming a pressure vessel liner are disclosed. One method includes forming an extruded tube by extruding a parison through a die and a mandrel and forming main body sections and return line sections in the extruded tube according to a first pattern. A cross-sectional area of the return line sections is smaller than a cross-sectional area of the main body sections. The method further includes changing the pattern according to which the main body sections and the return line sections are formed from the first pattern to a second pattern without stopping the forming of the extruded tube and forming the main body sections and the return line sections in the extruded tube according to the second pattern.

An extrusion head for pipes includes a first female body provided with a first through cavity and a male element inserted and supported in the first cavity, and defining with it a hollow space. A second female body is attached to the first female body and provided with a second through cavity. An interchangeable male body is attached cantilevered on the male element and positioned in the second cavity. The second female body and the interchangeable male body define a passage gap in fluidic communication with the hollow space. In the second cavity, a housing seating is made in which an adjustment ring is positioned, through which the interchangeable male body is positioned through, and adjustment members configured to adjust the position of the adjustment ring.

A modular disk coextrusion die is formed of a plurality of cells stacked together. Each cell includes a symmetrical arrangement of thin annular disks, including a central routing disk and two distribution disks on both sides of the central routing disk. The distribution disks are oriented so that their respective distribution inlet openings oppose each other by about 180 degrees. The symmetrical arrangement permits each cell to process the melt streams in a manner that provides enhanced layer uniformity and bubble stability. By stacking several cells, blown films having up to several hundred layers can be made using twelve, twenty-four or more polymer melt streams.

A modular disk coextrusion die is formed of a plurality of cells stacked together. Each cell includes a symmetrical arrangement of thin annular disks, including a central routing disk and two distribution disks on both sides of the central routing disk. The distribution disks are oriented so that their respective distribution inlet openings oppose each other by about 180 degrees. The symmetrical arrangement permits each cell to process the melt streams in a manner that provides enhanced layer uniformity and bubble stability. By stacking several cells, blown films having up to several hundred layers can be made using twelve, twenty-four or more polymer melt streams. Complex films made from the modular disk coextrusion die are also provided.

An extrusion die includes a plurality of studs, a tuning assembly and a restrictor member. The tuning assembly comprises a wedge member, first and second adjustment members, and an adjustment control having a rotatable single point adjustment member. The wedge member is coupled to first ends of the studs and includes a first and second plurality of channels within. The first and second adjustment members have a plurality of protrusions, each of which is positioned within a respective one of the first and second plurality of channels. The restrictor member extends in the longitudinal direction and is coupled to second ends of the studs. Rotation of the single point adjustment causes each of the protrusions to move within each respective channel forcing the wedge member, the studs, and the restrictor member to move in a direction that is substantially perpendicular to the longitudinal direction.

Extrusion die systems, die changers and related methods are provided herein. The die changer for changing of dies in and out of an extrusion line can include a housing having a main supply feed bore therethrough for directing a flowable material and a channel oriented transversely to the main supply feed bore. The die changer can include a slide plate movable through the channel and transverse to a direction of flow through the bore. The slide plate can include an elongate body having a first section and a second section. A first bore can extend through the first section of the elongate body of the slide plate and a second bore can extend through the second section of the elongate body of the slide plate. The slide plate of the die changer can be moved within the channel of the housing between a first position where the first bore in the first section of the elongate body of the slide plate is aligned with the main supply feed bore and a second position where the second bore in the second section of the elongate body of the slide plate is aligned with the main supply feed bore.

The present disclosure generally relates to extrusion die systems. In particular, the present disclosure relates to a specialty pin cam nut designed for the ease of assembly and disassembly of extrusion dies.

The present invention provides a system and method for quickly removing and installing a filament tube and nozzle in an FFF extrusion system. The system utilizes a primary manifold that includes a cooling block, a heating block and a quick-change mechanism. This primary manifold is adapted to mate a filament tube/nozzle assembly. The quick-change mechanism, which in a particular embodiment utilizes a recessed biased-bearing arrangement, enables the filament/nozzle assembly to be removed and inserted without the use of any tools, and without causing any significant downtime for the FFF extrusion system. Once removed, the filament tube/nozzle assembly can be refurbished by a technician, trained so as not to over torque the tube/nozzle threaded interface. This refurbishment (typically consisting of a cleaning and the installation of a new nozzle) could be accomplished off-line, without any impact on the continued use of FFF extrusion system.

A device produces plastic pipes by extrusion, involving an extruder, a pipe head connecting to the extruder in production direction, having a base material, mandrel, and sheath. A melt channel, formed between the mandrel and sheath in production direction, promotes flow at least at the mandrel and sheath end, the mandrel and sheath being adjustable forwards and backwards relative to one another, and the outer mandrel surface and/or the inner sheath surface at least partially having a material with greater sliding capacity than the base material. Mandrel diameter at the end conically widens or narrows, and/or the mandrel end is curved so the diameter widens, narrows, or remains constant, and the inner sheath diameter at the end conically widens, narrows, or remains constant, and/or the sheath end is curved so the diameter widens or narrows, or two further surface sections, parallel and cylindrical, extend at the mandrel and sheath end.

The disclosure relates to an extruder head for extruding cord reinforced extrudate, wherein the extruder head includes a die and a cord guide, wherein the extruder head further includes a first flow channel that extends along a first flow path through the extruder head at and debouches into the die from a first side of a cord plane and a second flow channel that extends along a second flow path through the extruder head at and debouches into the die from a second side of the cord plane, wherein the first flow path and the second flow path each include a supply section and a coat-hanger section, wherein the first flow path and the second flow path, in their respective coat-hanger sections, extend within a first range of eighty-five to ninety-five degrees with respect to the cord plane along at least seventy percent of the coat-hanger sections.