Abstract: A material for use in lining pipes is disclosed. A warp-knitted tubular fabric (24, 64) in which the stitch used (for example a tricot stitch) is of a type that reconfigures as the tube is expanded radially to contract longitudinally is sufficiently flexible and compressible to enable it to conform to pipe structures. The fabric of this invention is infused with resin, which is cured once the liner is in place within the pipe. Potentially, this fabric may be thinner than known prior art materials, but exhibits comparable strength and conformability, which are necessary characteristics in the repair or rehabilitation of pipes. The use of a thinner fabric material reduces constriction of the pipe bore by repair and also offers the potential for cheaper lining material, as less resin is required. The fabric may be knitted from glass fibre yarn, which is non-toxic and a stronger material than generally used in the prior art.

Abstract: An inflatable element in the form of a tension tube, and method of making same. The method involves forming a tube by a knitting process, then heatsetting the tube whilst simultaneously maintaining it under lengthwise tension. The tension in the tube is maintained during cooling of the tube. An option relaxation stage may also be included.

Abstract: A method for producing a polyolefinic film having ultraviolet stabilizers by extruding a hot molten polymer into a water quench bath for solidification of the film. An active halogen is added to the water quench bath in order to reduce the water carryover when the polyolefinic film is withdrawn from the water quench bath.

Abstract: A composite sheet material which is particularly useful as a backing material for carpet underlay is a stitched crepe paper sheet 5 with rows of apparent projections 13 formed therein between parallel rows of stitches 10 by deforming the crepe paper sheet without puncturing the paper. The stitches 10 substantially restrict the extensibility of the crepe paper sheet 5 and the apparent projections 13 are formed at a position in the crepe paper sheet 5 directly in line with the ends 11 of the stitches 10. According to the preferred method, each apparent projection 13 is in reality a depression between two projections formed in the opposite surface of the crepe paper sheet without puncturing the paper. In an alternative embodiment there is a pair of apparent projections 13 formed in the crepe paper sheet 5 between adjacent rows of stitches 10.

Abstract: A composite sheet material which is particularly useful as a backing material for carpet underlay is a stitched crepe paper sheet 5 with rows of apparent projections 13 formed therein between parallel rows of stitches 10 by deforming the crepe paper sheet without puncturing the paper. The stitches 10 substantially restrict the extensibility of the crepe paper sheet 5 and the apparent projections 13 are formed at a position in the crepe paper sheet 5 directly in line with the ends 11 of the stitches 10.According to the preferred method described, each apparent projection 13 is in reality a depression between two projections formed in the opposite surface of the crepe paper sheet without puncturing the paper. In an alternative embodiment there is a pair of apparent projections 13 formed in the crepe paper sheet 5 between adjacent rows of stitches 10.

Abstract: In a method of producing composite sheet material by forming longitudinal rows of stitches 7 in a paper sheet material 1, the length of paper sheet material 1 used per stitch 7 is increased so that there is entrapped within each stitch 7 in each longitudinal row of stitches 7 a portion of paper sheet material 1 having a length greater than the length of the completed stitch 7. In consequence there are formed in the composite sheet material a longitudinal series of laterally extending corrugations, ridges or ribs which, in the case of a crepe paper sheet material 22, constitute a gross crimp imposed without distortion of the crimps in the initial crepe paper sheet material 22.