LAMINATE

Abstract: This invention relates to a laminate for lining a passage, entirely or partially surrounded by walls, on or under the ground, comprising at least one layer of a reinforcement of continuous fibres, curable resin and a plastic foil or a plastic film, which is on the inside of the laminate when this one is introduced into the passage that shall be lined, there being arranged a fabric of fibres between the inner film and the reinforcement, which fabric on its side turned to the inner film carries cut fibres, and which together with its cut fibres form a combination fabric, absorbing resin, for concentration of curable resin to the inner surface of the cured laminate. According to the invention the laminate is characterized by the fact that the fabric (6) comprises at least two layers (8-10), put together, each one of which in an inactive position having two essentially parallel side portions (A, B), and which are displaced in relation to each other in such way that in an active position, i.e. when the side portions (A, B) are laid to a ring, there is formed a joint between the one side portion (A) of the one layer (8, 9) and the other end portion (B) of the other layer (9, 10), the remaining end portions (B, A) of the two layers (8, 9; 9, 10) are positioned in that way that they cover the joint on each side, and the joint arrangement making it possible for the end portions of the layers to be able to slide in relation to each other during the installation/expansion phase.

Description: LAMINATE This invention relates to a laminate for lining a passage, entirely or partially surrounded by walls, on or under the ground, for instance pipelines for gas, water and/or a sewerage, channels for instance for ventilation, smoke and the like, comprising at least one layer of a reinforcement of continuous fibres, curable resin and a plastic foil or a plastic film, which is on the inside of the laminate when this one is introduced into the passage that shall be lined, there being arranged a fabric of fibres between the inner film and the reinforcement, which fabric on its side turned to the inner film carries cut fibres, and which together with its cut fibres form a combination fabric, absorbing resin, for concentration of curable resin to the inner surface of the cured laminate. Such a laminate is previously known by the international patent document WO 92/14606. As appears from this patent document the fabric of glass fibres has an axial joint. In this connection the portions adjacent to the joint are laid in that way that they overlap each other, which leads to a local increase of the thickness of the laminate. This in its turn can lead to high stress concentrations in this area with local increase of the thickness with a deteriorated life length of the laminate as a result. This invention intends to remove the problem with known technique and to provide a new laminate where the risk of increased stress concentrations is essentially eliminated. This has been made possible by a laminate of the type mentioned by way of introduction, which has the features mentioned in the claims. A preferred embodiment of the invention shall be described in more detail below with reference to the accompanying drawing, where Fig. 1 shows a section of the laminate in place in a passage, and Fig. 2 shows the construction of a fabric being a part of the laminate. With reference to fig. 1 is shown there in section a part of a lining laminate 1 introduced in place inside a passage 2, surrounded by walls, for instance a pipe line that shall be lined and be held pressed against the wall 3 of the passage. Besides at least one and preferably more plaited reinforcement layers 4 of the kind mentioned above and an inner film 5 which only functions as a protection until the resin of the laminate has been forced to cure and which thereafter can be removed, the embodiment of the lining laminate according to the invention, shown in the figure, comprises a fabric 6 which is made of continuos glass fibres and which on its side turned to the inner film 5 carries cut fibres 7, preferably cut glass fibres, forming a combination fabric. The cut fibres can constitute a mat which is laid on the fabric 6. The material of the plaited reinforcement 4 is composed of roving and the roving can be of "KOSMOS", conventional or bulked type. The glass fibre, being a part of the combination 2 fabric, i.e. the fabric 6 together with the cut glass fibres 7 put in it, can be composed of E-, ECR-, ADVANTEX-, C-glass or of other fibre materials of high quality. The fabric 6 with cut glass fibres 7, denoted combination fabric, has among other things that quality that it absorbs resin to an essentially larger extent than the reinforcement 4 and due to that fact the resin, being part of the laminate 1, will in first hand be absorbed by the combination fabric 6, 7 until this one is saturated and thanks to that fact a concentration of resin to the inner surface portion or surface layer of the laminate is obtained. Thus, when the resin has been forced to cure, an internal surface layer comprising solely resin with cut glass fibres as a reinforcement is obtained, which layer is resistant to corrosion. At the same time the cured resin intimately connects the combination fabric 7 with adjacent reinforcement layer 4 so that a lining with a very high strength is created. The fabric 6, being part of the laminate, has a joint which extends in axial direction and comprises according to this embodiment three layers 8-10, put together. In this connection the three layers have in the starting-point displaced positions in relation to each other, which is shown in fig. 2. In this figure are shown three layers 8-10, which are essentially of the same size, and which have been put on top of each other but are laterally displaced. In this connection the displacement is made in that way that the axial side portion B of the layer 8 has been pulled out outside the axial side portion B of the layer 8, the axial side portion B of which has been pulled out outside the axial side portion B of the layer 10. This means that the axial side portion A of the layer 8 has landed inside of the axial side portion A of the layer 9 with the same distance as the side portion B of the layer 8 is positioned outside the side portion of the layer 9, and that the axial side portion A of the layer 9 has landed inside the axial side portion A of the layer 10 with the same distance as the side portion B of the layer 9 is positioned outside the side portion B of the layer 10. When laying together the side portions A and B to a ring, is obtained such an arrangement shown in fig. 1, i.e. the portion 9A touches the portion 10B, the portion 8 A touches the portion 9B, whereas the portion 10A is landed on the top and the portion 8B at the bottom. As is apparent from fig. 1 the portion 10A and the portion 8B pass with a good distance the joint between the portions 9 A and 10B and the joint between the portions 8 A and 9B, respectively. Due to that fact these joints are protected. The shown arrangement implies that the local increase of the thickness and by that the stress concentrations in this case become considerably less than what would be the case if the side portions would overlap each other as is shown in the mentioned WO-document. 3 Furthermore, the described joint arrangement makes possible that the end portions of the different layers can slide in relation to each other during the installation/expansion phase. This fact makes the new laminate very flexible and adaptable, seen from a diametric point of view. During the curing which can be made by means of UV-light, which is emitted from an apparatus, which passes through the lining with a controlled speed at the same time as compressed air presses the laminate towards the wall of the passage. This means that the fabric 6 is stretched out, i.e. the end portions of the layers, put together, slide in relation to each other in that way that there will be a distance in the joint between the A- and the B portions of the layers. In the figure there is shown two distances ai and a 2 . In this connection ai constitutes the distance between the end portion of 8B and the joint between 8A/9B, whereas a 2 constitutes the distance between the joint 9A/10B and the end portion of 10A. It is important that the joint arrangement is designed in that way that the distances ai and a 2 (see Fig. 1), which in the normal case are essentially of the same size, always are larger than the stretching out of the fabric 6, which means that the joint 9A/10B is landed inside the end portion 10A of the layer 10, whereas the joint 8A/9B is landed inside of the other end portion 8B of the layer 8. This fact means that the mentioned joints are protected by the end portions 10A and 8B, which leads to an extremely good strength of the laminate. The invention is of course not limited to the mentioned embodiment but can be modified within the scope of the following claims. Thus, the fabric being a part of the laminate could consist of only two layers or more than three layers.

Claims: 4 Claims 1. A laminate for lining a passage, entirely or partially surrounded by walls, on or under the ground, for instance pipe lines for gas, water and/or a sewerage, channels for instance for ventilation, smoke and the like, comprising at least one layer of a reinforcement of continuous fibres, curable resin and a plastic foil or a plastic film, which is on the inside of the laminate when this one is introduced into the passage that shall be lined, there being arranged a fabric of fibres between the inner film and the reinforcement, which fabric on its side turned to the inner film carries cut fibres, and which together with its cut fibres form a combination fabric, absorbing resin, for concentration of curable resin to the inner surface of the cured laminate, c h a r a c t e r i z e d in that the fabric (6) comprises at least two layers (8-10), put together, each one of which in an inactive position having two essentially parallel side portions (A, B), and which are displaced in relation to each other in such a way that in an active position, i.e. when the side portions (A, B) are laid to a ring, there is formed a joint between the one side portion (A) of the one layer (8, 9) and the other end portion (B), of the other layer (9, 10), the remaining end portions (B, A) of the two layers (8, 9; 9, 10) being positioned in that way that they cover the joint on each side, and the joint arrangement making it possible for the end portions of the layers to be able to slide in relation to each other during the installation/expansion phase. 2. A laminate according to claim 1, the fabric comprising three layers (8-10), put together, and the layer (8) being positioned on top and the layer (10) at the bottom at the starting point, c h a r a c t e r i z e d in that the first end portion (9 A) of the intermediate layer forms, radially seen, an outer joint with the second end portion (10B) of the lowermost layer, that the first end portion (8B) of the uppermost layer forms, radially seen, an inner joint with the second end portion (9B) of the intermediate layer, and that the first end portion (10A) of the lowermost layer and the second end portion (8B) of the uppermost layer cover the mentioned joints (9 A/10B) and (8A/9B) in such a way that even if the end portions of the layers slide in relation to each other at respective joint, the joints (9 A/10B) and (8A/9B) will be covered by the mentioned end portions (10A, 8B).

Inventors: PERSSON BOERJE, PERSSON, BOERJE
Applicants: INPIPE SWEDEN AB, PERSSON BOERJE, PERSSON, BOERJE
Application year: 1999
Main classification: B32B1
IPC codes: B29C53, B29C63, B29C70, B32B1, B32B17, B32B27, F16L55, F16L58