Cured-in-place pipe liner

Abstract

A CIPP liner for repairing a sewer pipe comprises a cover fabric (1) and a base fabric (2) to be attached to each other using needle punch technology, as well as a stretchable plastic membrane (4) attached to the base fabric (2) with a flexible glue (3), into which flexible glue (3) also the with each other mixed fibres (5) of the cover fabric (1) and the base fabric (2) are glued. From this material, a CIPP liner corresponding to the dimensions of the sewer pipe is cut and sewn, the sewing seam of which is further taped.

Claims

1. A method for producing a CIPP liner, comprising the steps of: stretching a base fabric (2) in one or more directions; arranging an evenly spread cover fabric (1) against the base fabric (2) stretched in one or more directions; pressing needle punch needles (7) from the side of the cover fabric (1) through the cover fabric (1) and the base fabric (2), thereby mixing the fibres of the fabrics (1) and (2) with each other and the mixed fibres (5) extend to the outside of the surface of the base fabric (2); removing the needle punch needles (7); attaching the base fabric (2) and a plastic membrane (4) to each other with a flexible glue (3), wherein, at the same time, the mixed fibres (5) are attached by the glue (3) to each other thereby producing the cover fabric (1) arranged in both longitudinal and transverse directions in waves and/or pleats attached to the base fabric (2); and cutting and sewing a piece of the requisite size of the CIPP liner from the created CIPP liner fabric, and taping the sewing seams once the glue (3) has dried.

2. The method according to claim 1 further comprising the step of: cutting the CIPP liner according to the diameter of the sewer pipe, to provide a flexible CIPP liner, wherein the cover fabric (1) and the base fabric (2) are made of different materials and having different maximum lengths of elongation and wherein the plastic membrane (4) is a stretchable plastic membrane (4).

3. The method according to claim 2, wherein as the cover fabric (1) is stretchable so that it is in its stretched state it is 70-80 percent larger than in its non-stretched state.

4. The method according to claim 2, wherein as the base fabric (2) is has different elongation properties in relation to the longitudinal and transverse directions.

Description

(1) In the following, the invention is described in more detail with reference to the accompanying drawings, in which

(2) FIG. 1 shows a cross-section of the fabric structure of a CIPP liner according to the invention.

(3) The cover fabric 1 is teased and placed against the base fabric 2, after which, from the side of the cover fabric 1, the needle punch needles 7 are pressed through the cover fabric 1 and the base fabric 2, wherein the fibres of both fabrics 1 and 2 mix with each other and the mixed fibres 5 extend to the outside of the surface of the base fabric 2. The needle punch needles 7 are removed. The base fabric 2 is glued with flexible glue 3 to the plastic membrane 4, at the same time gluing the mixed fibres 5 to each other. Thus, an elastic layer 6 between the base fabric 1 and the cover fabric 2 is formed. When the glue 3 has dried, from the CIPP liner fabric created, a piece of the requisite size is cut and sewn into the shape of a CIPP liner and the sewing seams are taped.

(4) There are many alternative implementations for the invention, for example, the use of two cover fabrics instead of one in the CIPP liner.