Abstract: A material for use in lining pipes includes inlay yarns that are interlinked by warp-knitted yarns. One set of inlay yarns extends in a machine direction, contributing to the fabric's strength in this direction. Two further sets of inlay yarns follow paths that step alternately between displacements to the left and right. This construction results in a series of short lengths of yarn aligned to provide the fabric with cross-directional strength. The inlay layers are loosely held, allowing them to slide relative to each other and the straight inlay yarns may move apart to a small degree. The result is a strong, flexible fabric that retains sufficient expansion for use in a pull-in-place liner. A method of preparing a multilayered pipe-lining fabric involves repeated steps of layering flat sheets above and below a flattened carrier tube, bonding the sheets, then flattening the structure along fold lines circumferentially rotated from the first.

Abstract: A material for use in lining large-diameter pipes is disclosed. A textile material formed to a tubular shape and impregnated with resin may, on curing the resin, repair a damaged pipe in a cure in place pipe (CIPP) rehabilitation process. The present invention provides both a novel structure of tubular material and a novel method of preparing the material for use in a CIPP rehabilitation process, specifically aimed at large-diameter pipes such as oil rig caissons. The tubular material of this invention comprises four sheets of a double-bed warp-knitted fabric (40). A first pair of sheets (52) are arranged to form, respectively, inside and outside surfaces of a first half-tube, with fabric machine direction extending along the length of the half-tube. The second pair of sheets (52a) are similarly arranged to form a second half-tube. The two half-tubes are connected at a pair of longitudinally extending joins (58, 60).

Abstract: A material for use in lining large-diameter pipes is disclosed. A textile material formed to a tubular shape and impregnated with resin may, on curing the resin, repair a damaged pipe in a cure in place pipe (CIPP) rehabilitation process. The present invention provides both a novel structure of tubular material and a novel method of preparing the material for use in a CIPP rehabilitation process, specifically aimed at large-diameter pipes such as oil rig caissons. The tubular material of this invention comprises four sheets of a double-bed warp-knitted fabric (40). A first pair of sheets (52) are arranged to form, respectively, inside and outside surfaces of a first half-tube, with fabric machine direction extending along the length of the half-tube. The second pair of sheets (52a) are similarly arranged to form a second half-tube. The two half-tubes are connected at a pair of longitudinally extending joins (58, 60).

Abstract: An irrigation pipe is formed from a sheet rolled into a tube about a longitudinal axis, and having overlapped lateral margins. The sheet has a fabric layer and an outer layer formed on the fabric layer. The pipe includes axially extending load bearing members which are in contact with the outer layer. The load bearing members are lacking at least in the vicinity of one or both of the overlapped lateral margins.

Abstract: An irrigation pipe is formed from a sheet rolled into a tube about a longitudinal axis, and having overlapped lateral margins. The sheet has a fabric layer and an outer layer formed on the fabric layer. The pipe includes axially extending load bearing members which are in contact with the outer layer. The load bearing members are lacking at least in the vicinity of one or both of the overlapped lateral margins.