A method of making a rubber hose includes the steps of providing an inner rubber layer including a hollow part, and forming a first braided layer on the inner rubber layer by braiding a plurality of first yarn materials including a vinylon fiber made by a dry process such that the braided first yarn materials includes a braid formed in a three-over, three-under pattern. Next, a middle rubber layer is formed on the first braided layer. A second braided layer is then formed on the middle rubber layer by braiding a plurality of second yarn materials including a vinylon fiber made by a wet process such that the braided second yarn materials includes a braid formed in a two-over, two-under pattern. Finally, an outer rubber layer is formed on the second braided layer.

A multilayer flexible tube includes an inner layer including a melt processable fluoropolymer, wherein the fluoropolymer includes a copolymer of a poly vinylidene fluoride (PVDF) and a hexafluoropropylene (HFP); and an outer layer including a melt processable polymer having a shore hardness less than a shore hardness of the inner layer. Further provided is a method of making the multilayer flexible tube.

The invention relates to a lining element (10) for the rehabilitation of a pipeline, having a carrier layer (16) consisting of an expandable, resin-absorbent material which, in the longitudinal direction (L.sub.1, L.sub.2) of the carrier layer (16), has a first expansion rigidity, and a stiffening structure (24) which, in the longitudinal direction (L.sub.1, L.sub.2) of the carrier layer (16), has a second expansion rigidity, wherein the first expansion rigidity is lower than the second expansion rigidity and wherein the stiffening structure (24) is incorporated into the carrier layer (16).

A tubular liner for the lining of pipelines has an inner tubular film, a layer of fibrous material arranged on the inner tubular film, and an outer tubular film which is arranged on the outer side of the fibrous material and is impermeable to UV light. The tubular liner is distinguished in that the outer tubular film has a radially inward peripheral portion and a second peripheral portion bearing on the outer side of the first peripheral portion in an overlapping region. The peripheral portions are connected to one another by an adhesive tape which extends across the longitudinal direction of the tubular liner. A method is also provided for manufacturing such a tubular liner.

The invention relates to a lining element for repairing a connection area between a main pipe and a branch pipe, the lining element including a layer of resin-absorbing material, wherein at least six flexible, expandable lining parts are connected to each other by at least six connections to form the lining element. To manufacture such a lining element the at least six flexible, expandable lining parts are provided and connected to each other by at least six connections to form the lining element.

A lining element for repairing a connection area between a main pipe and a branch pipe, comprising a layer of resin-absorbing material, wherein at least three flexible, expandable lining parts are connected to each other by at least three connections to form the lining element. Each lining part comprises a main pipe section and a branch pipe section, and side edges. The lining element is characterized in that the lining parts are connected to each other by connecting both side edges of the adjacent branch pipe sections and side edges of adjacent main pipe sections in a continuous fashion.

A method of manufacturing a vent for a pipeline liner comprises overmoulding a porous element in a polymer body. This produces a vent in which the element extends across, and is in fluid communication with, a through-passage formed in the body during overmoulding. The element is supported in a mould cavity clamped between opposed internal mould formations that define at least part of the through-passage. The integrity of the vent and of the interface between the vent and the liner is maintained during die-drawing of the liner. Thus, the porous element is mechanically engaged with the surrounding body as flowable material of the body is absorbed into the element during overmoulding. Internal flanges also restrain the element against movement along the through-passage. The vent is also fused with the liner by heating interface regions to a softening or melting temperature before inserting the vent into a wall of the liner.