EP1224346A1

EP1224346A1 - Textile material in sheet form for technical uses

Info

Publication number: EP1224346A1
Application number: EP00968004A
Authority: EP
Inventors: Michel Serillon
Original assignee: Fils dAuguste Chomarat et Cie SA
Current assignee: Chomarat Composites SAS
Priority date: 1999-10-25
Filing date: 2000-10-11
Publication date: 2002-07-24
Anticipated expiration: 2020-10-11
Also published as: NO20021629D0; TR200200914T2; NO20021629L; PL355847A1; DK1224346T3; JP2003513174A; HUP0203329A2; DE60008570D1; US20030024592A1; CA2385561C; NO321239B1; ES2211625T3; EP1224346B1; AU7797900A; ATE260353T1; WO2001031100A1; FR2800100A1; BR0015034A; CZ20021394A3; FR2800100B1

Abstract

The invention relates to a textile material in sheet form, consisting of a warp and weft fabric produced by rovings of continuous technical filaments (glass, carbon, aramide) without torsion. The invention is characterised in that the fabric is produced according to a plain weave or derivative thereof, the density of the warp (C) and the weft (T) being balanced; the warp threads (C) or weft threads (T) are weakened or cut individually at predetermined intervals without any noticeable deterioration in the characteristics of the weft or warp threads situated beneath the weakening or cutting area; and the areas in which a series of threads of the fabric (C) or (T) are weakened or cut are produced with a lateral and vertical thread course between two consecutive threads.

Description

MAT TEXTILE TABLECLOTH MAT FOR TECHNICAL USES

Technical area

The present invention relates to a new type of textile textile material usable for technical uses, such as structures for reinforcing composite materials, laminate complexes, complexes making it possible to achieve sealing in the field of building, or public works, complexes intended for the repair of pipes and, more generally, for any type of structure comprising a matrix based on resin, polyester or other, reinforced by a textile reinforcement ply.

Previous techniques

The use of textile tablecloths, in particular based on glass fibers, has been proposed for decades, to carry out the reinforcement of plastic material during the manufacture of laminated or molded structures, flat or in shape, as is apparent in particular from patents FR-A-1 469 065, FR-A-1 394271, US-A-3

930 091, FR-A-2 034 787 and FR-A-2 568 275.

Such textile structures have also been proposed for use in the field of building and public works for the production of waterproof screeds, in particular in reinforced bitumen (FR 2 409 338) to produce complexes usable for the repair of pipes. or similar works, buried or not (EP-A-542,639).

It appears from all these documents that the reinforcement structure must be adapted according to the various applications.

The basic structures proposed for decades to produce such reinforcements, in particular from the appearance of glass strands, are on the one hand, the mats which are made up of staple fibers and are in the form of a structure similar to a “felt”, and on the other hand, the warp and weft fabrics made up of roving yarns or ribbons made from continuous filament glass yarns.

In addition to these types of structures, "unidirectional" sheets have also been proposed in which the glass strands are arranged in the same longitudinal direction, these strands being bonded together either chemically (French patent 1,394,271), or by means of a seam (French patent 1,469

065).

It has also been proposed in US-A-3,930,091 to produce a ply, which unlike the previous ones, consists for the most part of glass fibers extending transversely relative to the length of said ply, these threads being linked between them by a loose tying chain, consisting of threads coated with a hot-melt or similar material, making it possible, after heat treatment in particular, to keep the weft threads parallel to each other.

Compared with balanced warp and weft fabrics, such unidirectional plies however do not make it possible to produce articles which are reinforced both longitudinally and transversely.

Furthermore, for many applications, there is the problem of having a reinforcing structure which can deform during its implementation, in particular when producing molded articles in shape.

In the case of a reinforcement in the form of a unidirectional ply, it is possible to obtain such “deformability” in the transverse direction with respect to the orientation of the threads, for example by using threads as binding threads elastic.

In the case of a balanced warp and weft fabric, it can be envisaged to obtain a possibility of deformation by selecting the weaving weave.

Indeed, it is well known that certain weaves of the satin, twill type, lead to deformable woven structures. However, the possibilities of deformation are limited to a few percent.

Such a problem of possibility of deformability of the reinforcement is also found in the context of the use of complex structures, constituted by a combination of a nonwoven mat and bidirectional or unidirectional woven structures, which are used in particular for the repair of pipes. according to a technique which consists in covering the internal surface of the structure to be renovated with a tabular structure made from a complex material flexible, comprising a fluid-impermeable membrane and a fibrous base structure which is impregnated with a non-polymerized synthetic resin and, after plating said complex against the surface of the work to be repaired, causing the resin to polymerize so as to form an internal "sleeving".

5

Regarding the installation of such a tubular structure inside the pipe to be renovated, two main techniques are currently used.

The first, which emerges more particularly from British patent 1,357

10 355, consists in introducing the tubular material previously produced inside the pipe to be renovated, so that the fibrous structure is positioned facing the surface to be renovated and that the impermeable surface layer is, in turn, located inside next to the flow area.

15 After installation over the entire length of the pipe, the sheath is pressurized, so that it comes to press against the internal surface. The resin is then polymerized.

Another technique, known as “inversion”, consists, as is apparent from British patent 1 449 455, of introducing the sheath previously formed with the sealed surface located outside, then, during the introduction to the inside the pipe, causing the said sheath to turn over, so that the fibrous structure comes into contact with the internal surface of the tube and the waterproof layer is located inside. 25

Such a procedure allows the fibrous structure to be impregnated with unpolymerized resin as it is placed inside the pipe.

Furthermore, the polymerization can also be carried out continuously, for example by light radiation.

These two techniques, and more particularly the technique of placing by turning, implies having a base material which has sufficient mechanical characteristics in the lengthwise direction to ensure the placing. Furthermore, it is desirable that the tubular structure can also present possibilities of deformation under the action of stresses exerted in the transverse direction in order to allow the sheath to press perfectly against the surface of the wall to be renovated when the structure is put under pressure, so that it perfectly matches the surface of the structure to be renovated.

Consequently, in all the uses using textile reinforcements in the form of plies, the problem may arise of having a possibility of deformation both in the long direction and in the transverse direction while preserving, in the final product ( laminated article, molded article, waterproofing sheet, complex for repairing pipes), high mechanical characteristics in all directions.

Statement of the invention

However, a new type of fabric has been found, and this is the subject of the present invention, which can be used either alone or in combination with other structures, such as nonwoven fibrous webs, reinforcement grids, etc. ., in order to constitute a complex which not only allows, during its implementation, to retain good mechanical characteristics, in particular tensile strength, both in warp and weft direction, while allowing deformation in the another direction, and this by ensuring in the final product mechanical characteristics equivalent to those imparted by a non-deformable fabric.

The invention also relates to a method and an installation for the production of such a type of fabric as well as the use of the latter to produce complexes such as waterproofing coatings, structures for repairing pipes.

In general, the material according to the invention consists of a warp and weft fabric made from twist-free wicks of continuous filaments for technical use (glass, carbon, aramid, etc.), wicks which, in the following of the description, will be designated by the generic term "son". Such a fabric is characterized in that: - the fabric is produced in a plain weave or derived from plain, the density in warp and weft preferably being balanced; - The warp or weft threads are weakened or cut individually at predetermined intervals without significant deterioration in the characteristics of the weft or warp threads located below the weakening or cutting zone;

- the weakening or cutting zones of a series of threads of the fabric are produced with a lateral and vertical detachment between two consecutive threads or groups of threads.

In the present description, by "two wires or groups of consecutive wires ^M , is meant that the embrittlement or cutting carried out is actually between two wires with offset of a neighboring wire, or possibly by groups of wires, for example simultaneously on the wire neighbor, this shift being made between two consecutive groups.

In the fabric according to the invention, the strands of filaments constituting the warp and weft yarns are in the form of flattened ribbons, of great width compared to the thickness, width advantageously between 3 mm and

15 mm, both in the warp direction and in the weft direction while the thickness is advantageously between 0.30 mm and 3 mm.

The warp and weft are based on wicks of continuous filaments for technical use, such as in particular glass rovings, the overall titer of which is advantageously between 200 tex and 9600 tex, each consisting of 1 to 8 rovings, having a unit titer between 200 to 4800 tex. These rovings are untwisted and the weight of the fabric is generally between 300 g / m ² and 3000 g / m ² .

The basic fabric is, as indicated above, a fabric produced in a plain weave or derived from plain. The plain armor, such as Gros de Tours, fluted, Gros de Naples, plaited or similar, makes it possible to easily vary the width of the strips of thread in the warp or weft direction.

The weakened areas, which will be produced either on the warp threads or the weft threads, are located on one of the faces of the fabric over the entire width of the locks, the interval between two weakening areas on a thread given is between 10 and 15 cm. These areas are offset from one wire to the wire adjacent to it. Thanks to such a design, a structure is obtained which, despite the embrittlement, or even the cutting of a series of its constituents (warp or weft threads), remains homogeneous and easy to handle and allows it to be used as such. what.

According to a preferred embodiment, such a fabric is, prior to the production of the weakened or cut areas, associated with a fibrous sheet based on staple fibers such as a glass mat, the connection of the two components being obtained by sewing , knitting, the columns of stitches extending parallel between the warp threads, preferably on either side of each thread although this is not imperative.

Possibly, the connection could be obtained by not carrying out a straight seam, but a real knitting of the type with thrown stitches, the columns of stitches extending on the face of the fabric whose constituents (warp or weft) must be weakened or cut , and the connecting flanges on the reverse side of the complex formed by the fibrous mat.

In such a case, the weakening or cutting of the wires is preferably carried out between two columns of meshes so as not to damage the latter.

The invention also relates to a method and an installation allowing the production of such a fabric or complex.

In general, the process according to the invention consists:

• to make a warp and weft fabric from wicks without twist of continuous filaments for technical use,

• to associate this fabric possibly with a fibrous mat, and it is characterized in that a total or partial cutting of the warp or weft threads is carried out, at regular intervals, on one of the faces of the fabric, without total deterioration of the weft or warp thread, located at the level of the embrittlement zone below the cut thread, this cutting being carried out with a lateral and vertical detachment between two consecutive threads with a lateral and vertical detachment between two consecutive threads or groups of juxtaposed threads working in the same way in the weave of the fabric and this, so that two consecutive yarns (or groups) can slide relative to each other when the material is used.

Such a method can be implemented on an installation which also forms part of the invention, an installation which is characterized in that it comprises, arranged between a supply station and a reception station, an assembly making it possible to carry out the cutting the warp or weft threads of the fabric, at regular intervals and offset from one thread to the next thread (or group of threads), said assembly comprising: - two cylinders driven in synchronism with the movement of the fabric;

- one of the cylinders comprising on its surface a series of blades whose width corresponds substantially to the width of the wires (or groups) to be cut, said blades being offset relative to each other, both laterally and circumferentially in a drawing reproducing a type of armor ^(< satin _» .

When it is desired to cut the warp threads, these blades will be arranged transversely, while in the case where it is desired to cut the weft threads, they will be arranged circumferentially.

The second cylinder is a counter-cylinder coated with a layer of rubber or other elastomer, the pressure between the two cylinders being adjustable.

Such an installation makes it possible to control the precision of the action of the knives so that the cutting is carried out only on the warp (or weft) thread of the visible fabric without deterioration of the weft or the warp thread situated below it. this.

Brief description of the drawings

The invention will however be better understood thanks to the description which follows and which is illustrated by the appended diagrams in which:

- Figure 1 illustrates, schematically, the structure of a fabric according to the invention before making fragile or cut areas;

- Figure 2 is a schematic graphic representation of a fabric produced in accordance with the invention; - Figure 3 is a schematic view of an assembly of an installation for making the weakened areas and; - Figure 4 is a schematic elevational view showing the general structure of the cutting assembly of such an installation.

How to carry out the invention Figure 1 schematically illustrates, in perspective, the basic structure of the fabric used in the production of a material according to the invention.

Figure 2 is, for its part, the graphic representation of such a fabric. In such a graph, each square represents the crossing points between the warp threads (C) and the weft threads (T).

When the warp threads pass over a weft thread, they are identified by the sign (+) and, when they pass below a weft thread, they are identified by the sign (0).

Such a fabric is produced in a plain weave or derived from plain, the density in warp (C) and in weft (T) being balanced.

To obtain a product in accordance with the invention, these warp or weft threads are weakened or cut individually at predetermined intervals. The weakening zones are represented in FIG. 2 by the black zones, and are produced with a lateral and vertical detachment between two consecutive wires.

Referring to the example illustrated by this figure 2, it can be seen that the weave ratio is four wires (C1, C2, C3, C4) for 12 frames (T1 to T12).

If such a fabric can be used such that, according to a preferred embodiment, it can be associated with a fibrous web based on staple fibers, such as glass mat, the connection of the components being obtained by sewing / knitting, said seams extending parallel between the warp threads, preferably on either side of each thread (C).

Various solutions can be envisaged for making the weakened zones, the essential point being, during this operation, that the weft (or warp) wire lying below the weakened wire is not appreciably affected by this operation, and that the consecutive warp (or weft) threads can slide relative to each other during the implementation of the fabric. Such an operation can be carried out on an installation as illustrated in FIGS. 3 and 4.

This installation comprises, arranged between a station (1) for unwinding the fabric or complex previously produced and a winding station (2), an assembly (3) making it possible to cut the warp or weft threads of the fabric at intervals. regular offset of a wire (Cl) relative to the neighboring wire (C2).

In this embodiment, the cutting assembly consists of two cylinders (4,5) rotated at the same speed as the fabric or complex (6). The upper cylinder has a series of blades (7) located on its surface, the width of which corresponds substantially to the width of the cut wires, said blades (7) being offset with respect to each other both laterally and circumferentially, so as to reproduce fabric structure.

When it is desired to cut the warp threads (C), these blades are arranged transversely as illustrated in FIG. 4, while in the event that one wishes to cut the weft threads, they would be arranged circumferentially.

The invention and the advantages which it brings will however be better understood thanks to the concrete examples of embodiment given below for information but not limitation.

Example 1

As previously stated, a warp and weft weave fabric is produced.

This fabric is made from wicks of glass threads having a global titer, both in warp and in weft, of 2400 tex each consisting of 2 elementary rovings of 1200 tex.

The weaving is carried out so that the warp threads (C) and the weft threads (T) appear, after the fabric has been produced, in the form of flattened ribbons having a width of 9 mm and a thickness of 0.5 mm. The fabric obtained weighs 500 g / m ² and has no stretch in either the warp direction or the weft direction.

According to the invention, this fabric thus produced is treated on an installation as illustrated in FIGS. 3 and 4.

In this installation, the cylinder (4) which has a diameter of 30 cm, is a smooth cylinder, coated with a layer of rubber.

The cylinder (5), the diameter of which is also 30 cm, is, in turn, provided with cutting blades (7) having a width of 10 mm, arranged along the generatrices of said cylinder.

The spacing between two consecutive slats in the same row is

108 mm, these blades being offset laterally from one row to the next. These blades protrude 3 mm from the surface of the cylinder.

The lateral offset between these blades is 9 mm and corresponds substantially to the width of the wicks (C).

After treatment, in the finished fabric, each warp thread has cut areas, at least partially, spaced from each other by a length equivalent to 12 picks, that is to say in the present case. about 108 mm.

The cutting zones are offset by one wire relative to the next wire by a value substantially equal to 3 picks.

After production, such a fabric is practically inextensible in the weft direction, whereas on the other hand, it can be deformed in the warp direction, and this thanks to the presence of weakened zones which allow a displacement of said warp threads relative to each other. to others.

However, such a fabric has resistance in the warp direction to allow it to be handled and used. This product can be used to produce shaped laminated materials, such as reinforcement of pipes of variable shapes, beams or profiles of variable section, shaped molded parts obtained by helical winding of the structure of the reinforcement and requiring deformation in one direction, for example when making wind turbine blades or fans.

Example 2

Example 1 is repeated except that before treatment for weakening the warp threads, the fabric is associated with a glass mat weighing 300 g / m ² .

The whole nonwoven fabric / mat is linked by sewing / knitting by means of binding threads having a titer of 16.7 tex.

The seams can be either simple chains, or form a knit.

In both cases, the mesh columns preferably extend on either side of each warp thread, and are located on the face of the fabric to be treated.

The connecting grids between the meshes are, in turn, located on the reverse side of the nonwoven mat.

Such a complex, after completion, weighs 810 g / m ² and has a thickness of 1.10 mm.

It is particularly suitable for being used for the production of complexes used for repairing pipes, as described in the preamble to the present application.

Claims

1/ Tablecloth textile material consisting of a warp and weft fabric made from twist-free wicks of continuous filaments for technical use (glass, carbon, aramid, etc.), characterized in that:

- the fabric is made using a plain weave or derived from a plain weave, the warp (C) and weft (T) density being balanced;

- the warp (C) or weft (T) threads are weakened or cut individually at predetermined intervals without significant deterioration in the characteristics of the weft or warp threads located below the weakening or cutting zone;

- the areas of weakening or cutting of a series of threads of the fabric (C) or (T) are produced with a lateral and vertical separation between two consecutive threads.

2/ Material according to claim 1, characterized in that the strands of filaments constituting the warp (C) and the weft (T) are in the form of flattened ribbons, of great width in relation to the thickness.

3/ Material according to claim 2, characterized in that the width of the filament wicks is between 3 mm and 15 mm, both in the warp direction and in the weft direction while the thickness is advantageously between 0.3 mm and 3mm.

4/ Material according to one of claims 1 to 3, characterized in that the interval between two weakening zones on a given wire is between 5 and 30 cm, these zones being offset from one wire to the wire which it is adjacent.

5/ Material according to one of claims 1 to 4, characterized in that it is associated with a fibrous sheet based on discontinuous fibers, the connection of the two components being obtained by sewing/knitting, the columns of stitches extending parallel between the warp threads, on either side of each thread. 6/ Process for producing a material according to one of the claims

1 to 5, which consists of:

• to produce a warp and weft fabric from untwisted rovings of continuous filaments for technical use, • to combine this fabric possibly with a fibrous mat, characterized in that a total or partial cutting of the warp or weft threads is carried out , at regular intervals, on one of the faces of the fabric, without significant damage to the weft or warp thread, located at the level of the weakened zone below the cut thread, this cut being made with a lateral and vertical release between two consecutive sons.

Installation for implementing the method according to claim 6, characterized in that it comprises, arranged between a supply station (1) and a reception station (2), an assembly (3) making it possible to carry out the cuts warp (C) or weft (T) threads from the fabric, at regular intervals and offset from one thread to the neighboring thread, said assembly comprising:

- two cylinders (4.5) driven in synchronism with the movement of the fabric;

- one of the cylinders (5) comprising on its surface a series of blades (7) whose width corresponds substantially to the width of the wires to be cut, said blades

(6) being offset relative to each other, both laterally and circumferentially according to a design reproducing a satin ^weave *.

8/ Installation according to claim 7, characterized in that the counter-cylinder (4) is coated with a layer of rubber or elastomer, the pressure between the two cylinders (4,5) being adjustable.