FI92570C - Material for repair of flow ducts, such as pipes and the use of the material - Google Patents

Description

92570

Material for repairing flow channels such as pipes and use of material.

The invention relates to the material set out in the preamble of claim 1 for repairing flow channels, such as pipes, and to the use of the material.

In the renovation of old, poor condition pipes 10, which is intended to repair cracks and breaks in the pipes, a flexible material with a curable material and the necessary reinforcing layer to give strength is now commonly used on the inner surface of the pipes. This material 15 is generally placed in pipes dug into the ground from the ground surface as a long tubular sock so that the pipes do not have to be dug up. Such a method, known for example as "Insituform" or "Paltem", is used on a very large scale.

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The material to be pushed inside the pipe is required to have a particularly high degree of flexibility, formability and strength, which has made it difficult to find suitable materials. In addition, since tube sizes vary and tubes often have sharp bends, flexibility and formability in particular are very important factors in the patch and repair material. Traditional reinforcing materials, such as woven fabric, staple fibers and longitudinal reinforcing yarns, are not suitable for 30 k.o. to the method because they limit the deformability of the repair blank in the longitudinal direction of the pipe, which is necessary during the blank installation step.

For example, European Application Publication No. 392026 35 discloses reinforcing layers in which the filaments are formed into regular textiles, such as fabric, knit or braid, which have a directional reinforcing effect. A similar problem arises in the solution disclosed in U.S. Patent 4,525,702, in which yarns are wound around the warp yarns in the fabric forming the base reinforcement. In addition, European application publication 278466 discloses filaments in a saSnnS1-5 woven structure which, together with the woven structure, provide a directional reinforcing effect.

The object of the invention is to provide a material which has the good flexibility required by different pipe sizes and a good reinforcing effect in all directions. The material for carrying out the invention is characterized by what is set forth in the characterizing part of the appended claim 1. A mat formed of continuous filament fibers into a mat having an reinforcing effect of 15 isotropic achieves the above-mentioned properties, which are desirable in connection with pipe repair materials. In addition, the appended subclaims 2-5 disclose some preferred embodiments of the material 20 according to the invention. Good strength in both the plane and depth directions of the material is obtained by tying the felt layer and one or more continuous fiber mats acting as a reinforcement layer together by needling. The reinforcement formed from the continuous fiber can be e.g. glass-25 fiber. According to a preferred embodiment of EraM, the material further applies a knitted layer, preferably made by the laying-in technique, to a knit which weaves separate yarns from the yarn forming the knitting loops.

According to the appended claim 6, the use of the material according to the invention is directed to the repair of the flow channels of the material, such as pipes, in which the flexible material containing the curable material is placed on the inner surface of the channel and the curable material is cured.

The invention will now be described in more detail with reference to the accompanying drawing, in which Fig. 1 shows the use of a material according to the invention, Fig. 2 shows a reinforcement used in a material according to the invention, Fig. 3 shows a patch material according to the invention in a sectional view perpendicular to its plane; Figure 5 shows a patch material according to a third alternative, and Figure 6 shows a preferred type of knitting made by the laying technique which can be used in the patch material according to the invention.

Figure 1 shows the use of the material according to the invention. A tubular continuous sock 2 is inserted into a ground flow channel 1, such as a water pipe, sewer pipe or gas pipe, so that its other open end is fastened with a collar or the like 3 'around the mouth of the special guide pipe 3. The sock passes through the guide tube in such a way that its outer surface facing the blue tube to be patched is the inner surface of the inner tube of the guide tube, i.e. the sock is in a way inverted. a sock 2, such as a gas or a liquid, is used to push the sock 2 of this jaw inside the pipe 1 to be repaired, and the tubular sock 35 presses against its inner surface against the inner walls of the pipe 1 due to its deformability. In the final stage, the sock will be the inside of a pipe section of the same length as a tubular body surrounding the inner circumference of the pipe 92570 4 in the cross-sectional direction of the pipe, after which the sock 2 is cured by applying heat, e.g. by introducing hot water or gas inside the sock. Curing into the inner sealing layer 5 of the pipe takes place due to the heat-curable resin contained in the sock, such as, for example, epoxy resin or unsaturated polyester.

Figure 2 shows the reinforcement layer 5 according to the invention and used in the material in a direction perpendicular to its plane. The reinforcement layer consists of a so-called a continuous fiber mat formed by folding continuous fibers on a substrate into a suitably thick and dense mat. The fibers are filament-15 fibers, preferably glass fibers, and such a product is sold, for example, under the trademark "UNIFILORm." a low content of binder that does not interfere with the formation of the product and its folding properties, but nevertheless facilitates the handling of the reinforcing material during the manufacturing process of the material, so that the fibers can pile the binder so much that the mat remains well piled during handling.

Figure 3 shows the structure of the repair material according to the invention. The material 2 consists of a felt 30 6, which is a non-woven felt made of fibers.

The felt layer 6 and the mat 5 are most preferably bonded together by needling, i.e. the felt layer 6 and the mat 5 are mechanically bonded to each other in connection with the needling by means of the fibers of the felt layer which are attached to the filament fibers of the mat 5. If the filament fibers in the reinforcement are fiberglass, they remain intact enough in the needle to act as a reinforcement. A felt layer can also be provided

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92570 5 so that the fibers are fed as a carding mat to the mat 5, after which the needling takes place. A single reinforcing layer can also be provided by means of several overlapping continuous fiber mats 5.

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Figure 4 shows a particularly preferred structure in which the mat 5 is inside a felt layer. This is most preferably made by needling two separate layers of felt 6 on opposite sides 10 of the reinforcing mat 5.

Figure 5 shows a third structure, which is characterized in that in addition to the continuous nonwoven 5, a knitted layer 5 · is also used. In preparing the material, the reinforcement layers 5 and 5 'can first be driven on top of each other, after which the felt layers 6 can be bonded to the reinforcement layers 5 and 5' in the above-mentioned manner by needling them on both sides of the reinforcement structure formed by the layers 5 and 5 '. In addition to the continuous nonwoven 5, there may be several different types of reinforcing layers 5, e.g. the knit 5 'may be on both sides of the mat 5. It is also possible to attach a continuous fiber mat 5 to both sides of the knit 5 '.

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The material further comprises a thin surface layer 4 located on the surface of the repair material and indicated by a broken line in Figures 3, 4 and 5. The position of the felt layer 6 and the reinforcing mat 5 relative to each other should be such that the felt layer forms the outer surface of the composite material to which the surface layer 4 can be applied, e.g. by hot calendering. In this case, the material of the surface layer cannot penetrate the reinforcement in a way that interferes with its operation. For example, in the case of Fig. 3 35, the needling depth can be adjusted so that the fibers of the felt layer also form the outer surface of the material on the surface of the reinforcing mat 5. Layer 4 may be known from similar materials previously used, such as polyurethane, which is sufficiently used in terms of elongation and durability, such as polyurethane, which enters the inner part of the flow channel and insulates the other layers therefrom.

5 A heat-curable resin, such as an epoxy resin or an unsaturated polyester resin, can be impregnated into the material, e.g. just before use, by impregnating the felt layer 6 and the reinforcing mat 5 with the above-mentioned material.

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The material of the felt layer 6 is most preferably thermoplastic fibers, most preferably staple fibers. Polyes grain fibers are particularly well suited as felt materials due to their properties. Mineral-15 fibers, such as glass fibers, can also be used.

Reinforcing fibers other than glass, for example carbon or aramid, can also be used as the continuous filament fibers forming the mat 5. Mixtures of different filament-20 fibers are also possible. However, glass is the most expensive raw material for filament fiber in terms of price.

The non-reinforced basis weight 25 of filament fibers may be, for example, about 300 g / m 2, whereby the felt layers on both sides may weigh 300 to 450 g / m 2 per layer. Em. the figures naturally depend on the diameter of the pipe to be repaired, and the different layers can be dimensioned taking into account the strength and formability of the material.

Figure 6 shows a knitted structure 5 '# which is particularly well suited for use in the material according to Figure 5 as a reinforcement for a carpet 5. Knit is 3 5 ns. a knit made using the laying-in technique, i.e. it is reinforcing yarns separate from the yarn forming the knit, which run pSSasially in one direction inside the knit. Perusneule

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92570 7 is an interlock or double knit type S. The reinforcing yarns run in the transverse direction against the direction of the loop stitches in the knit and will be circumferential in the finished tubular patch material to provide radial strength. the reinforcing yarns may be monofilament or multifilament yarns, e.g. polyester or fiberglass. Thus, by means of the knitted layers 5 ', the isotropic reinforcement-10 effect produced by the continuous nonwoven 5 can be obtained in the desired direction, if desired. It should be mentioned that the knit also has good formability and strength.

The tubular sock formed by the repair material can be made, for example, by joining a planar, continuous blank 15 covering the felt 6 and the carpet 5 and any additional reinforcements 5 'together at its side edges.

The invention is not limited above only to the embodiments shown in the foregoing description and the accompanying drawings 20, but may be varied within the scope of the inventive idea set forth in the claims. Carpets made of continuous fibers other than fiberglass can also be used as a reinforcement layer. The method can be used in connection with all pipe repair operations, and materials other than the sock shown above can also be used as material. These are, at most, pieces of different shapes and sizes, made of a uniform blank, usually at least 4-5 mm 30 thick, with which the leak points in the pipes can be repaired. However, all kinds of pieces cut to a suitable shape or also shorter tubular pieces can be used, which are placed inside the pipe 35 to be repaired, and the strength, elongation and formability of the composite material can then be exploited. However, due to the special properties of the continuous non-woven mat, it is particularly well suited for use as a reinforcement of 92570 8 long tubular repair material, because in this context its above-mentioned properties are best used.

Claims (8)

92570 A material for repairing flow channels, such as pipes, consisting of a flexible material covering a surface layer (4), a fibrous felt layer (6) and a reinforcing layer, characterized in that the reinforcing layer (5) is of continuous filament fibers with an isotropic reinforcing effect. a structure formed by a pleated mat attached to a felt layer. Material according to Claim 1, characterized in that one or more continuous nonwoven mats and felt layers (6) acting as a reinforcement layer (5) are bonded together by needling. Material according to Claim 1 or 2, characterized in that the continuous fiber mat 20 in the form of a reinforcement layer (5) consists of glass filament fibers. Material according to one of the preceding claims 1 to 3, characterized in that it forms a tubular body. 25 Material according to one of the preceding claims 1 to 4, characterized in that the reinforcement is in addition to a continuous nonwoven knit (5 '), preferably a knit made by laying-in technique comprising reinforcing yarns. Use of a material according to any one of the preceding claims 1-5 in the repair of flow channels, such as pipes, wherein the curable material-containing flexible material (2) is placed on the inner surface of the channel (1) and the curable material is cured. > '2570 Use according to claim 6, wherein the material (2) is placed in the channel (1) as a tubular body covering the entire inner circumference of the channel. Use according to claim 7, wherein the placement takes place by pushing a tubular sock attached to the second end by means of a pressure of a medium, such as a gas or a liquid, from the pS of the flow channel (1). II 92570