A corrugator for an extrusion system for shaping a tubular plastic product, having a multiplicity of mould blocks, a guide track, along which the mould blocks are guided in each case in pairs during the operation of the corrugator from a starting region of the guide track towards an outlet region of the guide track, a first return track, along which the mould blocks are guided during the operation of the corrugator from the outlet region towards the starting region, and a second return track, with the aid of which individual mould blocks can be removed from the first return track and/or can be inserted into the latter during the operation of the corrugator.

A thin ribbon spirally wound polymer conduit and method of forming, wherein a helical reinforcing bead is interposed adjacent overlapping layers of ribbon. Further, a method of continuously forming spirally wound conduit wherein a sacrificial layer, preferably having a different base polymer to that of the conduit, is first applied to the former before the conduit is formed overtop.

A multi-component extrusion die head for producing a composite tube comprises an extrusion nozzle, a main die head, and a melt flow distributor device. The main die head is configured to supply the extrusion nozzle with a first melt flow and a second melt flow, which are guided separately from one anther in the extrusion nozzle away from the main die head and toward a nozzle outlet of the extrusion nozzle. The melt flow distributor device is arranged in the extrusion nozzle outside of the main die head and is configured to split the first melt flow in a peripheral direction thereof, and to supply the second melt flow to the first melt flow such that at least one section of the second melt flow is arranged within the first melt flow in the peripheral direction.

In a method for producing at least a single-walled tubular thermoplastic body in a machine, a nozzle head extrudes at least one tubular preform. The preform is expanded to a predefined dimension in a transverse direction and to a predefined shape in an expansion process using an expanding mandrel, the preform remaining open at the top and bottom. When the at least one preform has cooled off, the expanding mandrel is changed into a non-expanded state and the at least single-walled tubular body is removed from the machine.

A thin ribbon spirally wound polymer conduit and method of forming, wherein a helical reinforcing bead is interposed adjacent overlapping layers of ribbon. Further, a method of continuously forming spirally wound conduit wherein a sacrificial layer, preferably having a different base polymer to that of the conduit, is first applied to the former before the conduit is formed overtop.

Breathable medical circuit components and materials and methods for forming these components incorporate breathable foamed materials that are permeable to water vapor and substantially impermeable to liquid water and the bulk flow of gases. The materials and methods can be incorporated into a variety of components, including tubes, Y-connectors, catheter mounts, and patient interfaces and are suitable for use in a variety of medical circuits, including insufflation, anesthesia, and breathing circuits.

A modular plastic pipe formation apparatus to extrude plastic pipe is disclosed and includes a plurality of modules each having a transportable container and at least one component of the pipe formation apparatus located therein. The plurality of modules are aligned in a predetermined manner during formation of plastic pipe with the components aligned for pipe extrusion. The apparatus may also include a closed circuit fluid cooling system to provide cooling fluid to some of modules to cool the pipe being formed, the cooling circuit may flows in a counter direction to the direction of pipe forming in the pipe formation apparatus.

A corrugated pipe includes a corrugated pipe body circumscribing a hollow conduit and including alternating ribs and valleys extending along a longitudinal axis between a first end and a second end thereof. An electrically conductive wire is embedded in the corrugated pipe body, so that the wire spans adjacent ribs and valleys and extends substantially parallel to the longitudinal axis between the first and second ends.

Breathable medical circuit components and materials and methods for forming these components incorporate breathable foamed materials that are permeable to water vapor and substantially impermeable to liquid water and the bulk flow of gases. The materials and methods can be incorporated into a variety of components, including tubes, Y-connectors, catheter mounts, and patient interfaces and are suitable for use in a variety of medical circuits, including insufflation, anesthesia, and breathing circuits.

A method of continuously forming an axially extensible and retractable hose comprising: continuously forming an axially extending helix with axially spaced reinforcing coils from extruded thermoplastic material having a uniform cross-section along its length; and continuously bridging between an adjacent pair of the reinforcing coils with a continuous web of extruded thermoplastic material of substantially uniform width and relatively thin cross-section to form a continuous, helically extending sidewall, with the web having one of two opposite edge regions bonded continuously to a relatively flat outer bonding surface of a radially outwardly located portion of one of the adjacent pair of reinforcing coils, with the web having the other of the edge regions bonded continuously to a relatively flat inner bonding surface of a radially inwardly located portion of the other of the pair of reinforcing coils, and with the edge regions continuously radially separated from each other by the helix.