Abstract:
The polymeric pipes reinforced with a metal casing are used for transporting oil and gas, acids, alkali products, drinking water and industrial water, and also in the transportation of aggressive and neutral pulps. A metal-containing polymeric reinforced pipe includes a welded metal casing and a polymeric matrix having an amorphous-phase-based molecular structure. The metal-containing polymeric reinforced pipe is produced by extrusion moulding with simultaneous feeding of a polymer melt and the reinforcing metal casing into the mould cavity, followed by intensive cooling of the internal and external surfaces of the pipe being moulded. The invention increases the quality and endurance limit in the radial direction of the metal-containing polymeric reinforced pipe, productivity of the process for manufacturing the pipe, and also the strength and technological effectiveness of a pipeline constructed from the pipes produced.
Abstract:
This disclosure relates generally to corrugated pipe, and more particularly to corrugated pipe with a reinforcing stiffener. The corrugated pipe may include an axially extended bore defined by a corrugated outer wall having axially adjacent, outwardly-extending corrugation crests, separated by corrugation valleys. In some embodiments, a stiffener may be positioned within the corrugation valleys. In other embodiments, a stiffener may be positioned within the corrugation crests.
Abstract:
The invention relates to a method for roll-bending a profile which comprises at least one cross-sectional region which is formed from a plastics material which is shaped by extrusion. A first and a second bending roller set are provided, each including bending rollers which are arranged in such a way that a passage, which enables guiding of the profile, is formed between the bending rollers of each of the bending roller sets. The profile is bent about a first bending axis and about a second bending axis which is non-parallel thereto, the translations and rotations of the second bending roller set being brought about simultaneously at least at times and/or mutually offset in time in a predetermined sequence.
Abstract:
An assembly and process for forming a two stage extruded pipe having a central inner sleeve and a pair of outer attached lobes. The central sleeve shaped (also termed a grout receiving tube) is produced in an initial extrusion operation, following which it enters a cross head operation where a pair of outer lobes are attached to cross sectional exterior surface locations according to a second stage extrusion operation so as to be integrally formed therewith. Other steps include cooling of the dual stage extruded pipe, as well as sectioning and stacking the pipe. Additional steps include forming elongated slots or apertures into the central sleeve portion of the finished extrusion, such in non-interfering fashion with the individual passageway defining and lobes.
Abstract:
A method and apparatus for extrusion of an article is provided. A die assembly can apply flows of thermoplastic material to an array of reinforcing cables to form a composite extrusion. A slider fabric can be bonded to one side of the composite extrusion. After exiting the die assembly, the slider fabric can act to support the extrudate as it passes along an elongate mandrel, which can cause the base of the slider fabric to change shape from a flat profile to the final internal profile of the article. The extruded article can then be cooled to solidify the material. The die can include cooling for the slider fabric and means for promoting penetration of the thermoplastic into reinforcing cables.
Abstract:
A piece insertion method for a pipe, for example an irrigation pipe, including: ejecting at least one piece, for example a dripper, from an ejection unit, advancing the at least one dripper inside the irrigation pipe by a dripper advancing unit, lifting the dripper towards the inner surface of the irrigation pipe by using a lifting device such that the dripper is parallel or substantially parallel to this inner surface of the irrigation pipe on impact with this inner surface. The method according to the invention allows also coordination between the lifting device, the ejection unit and the dripper advancing unit such that the dripper spacing can be maintained in tight tolerances.
Abstract:
A method of extruding a cross-linked material, more particularly an insulating cross-linked material around an electrical cable. In an extrusion machine comprising a housing terminated with an extrusion head and provided with a filtering means adjacent the outlet end of said housing, the cross-linkable product is fed without addition of a cross-linking agent, said cross-linking agent being first introduced in said cross-linkable material downstream said filtering means. The cross-linkable material is kept in the housing at an elevated temperature to be in a fluid state, the cross-linking agent being introduced at a temperature slightly lower than its reaction temperature, whereby the extrudate may be at a temperature near the maximum temperature admissible for the extrusion of said material.
Abstract:
An apparatus for the continuous extrusion molding of a curable polymeric material about an elongated conductor. The apparatus includes electrical induction heating means for the precise and isolated application of heat to a limited portion of a progressively advancing mass of curable polymeric material immediately prior to its continuous entry into and passage through a forming die and its molding therein to shape.
Abstract:
In an extruder for the preparation of foamed resin insulated wires for telecommunication cables such as coaxial cables, a passage for a blowing fluid is provided to extend through the central portion of the extruder screw in the axial direction and open in the low pressure zone of the extruder, and at least one nozzle is mounted on the screw surface or the side face of the flight in the low pressure zone of the extruder to inject into and mix with into a molten resin a blowing fluid forwarded under pressure through said passage. The foamed resin insulated wires produced by the equipment have excellent electric and mechanical properties, in which the insulating resin coating has very high mechanical strength even at a very thin thickness. Further, the extrusion coating speed can be much increased when the above equipment is employed.
Abstract:
This disclosure relates generally to corrugated pipe, and more particularly to corrugated pipe with a reinforcing stiffener. The corrugated pipe may include an axially extended bore defined by a corrugated outer wall having axially adjacent, outwardly-extending corrugation crests, separated by corrugation valleys. In some embodiments, a stiffener may be positioned within the corrugation valleys. In other embodiments, a stiffener may be positioned within the corrugation crests.