FR3070401A1 - TEXTILE TAPE, DESIGNED FOR HIGH PRESSURE FLUID TRANSPORT CONDUIT FILLING - Google Patents

Abstract

Textile tape (1), designed for wrapping high-pressure fluid transport line, formed by weaving first-type (2) warp yarns with high tenacity, with weft threads (5) , characterized in that it comprises in the warp direction threads of a second type (3) having a lower title to the title of the son of the first type (2) and in which the second type warp threads (2) have a higher loading than the packing of warp threads of the first type (3).

Description

TEXTILE TAPE, DESIGNED FOR CONDUIT TAPE

FOR TRANSPORTING HIGH PRESSURE FLUIDS

Technical area

The invention relates to the field of technical textiles, and more particularly reinforcement textiles used for the manufacture of pipes for pressurized fluids. It relates more specifically to the manufacture of a reinforcing tape, intended to be wound in a helix on a tubular structure in order to reinforce the latter against the pressure differences between the inside and the outside of the pipe. It relates more specifically to a structure of this type of tape which has good dimensional stability properties under the conditions of tension applied during the manufacturing process for this type of pipe.

Invention background

In general, the pipes intended for the transport of high pressure fluids are used in various sectors, and in particular in the petroleum extraction industry. These pipes have a resistance to bursting by the presence of a layer in their structure which is formed of a textile tape of high mechanical performance, wound in a helix. To ensure good mechanical properties, the threads used in these tapes are based on high tenacity materials such as glass, carbon or aramid in particular. These ribbons are generally unidirectional ribbons having most of their fibers in the warp direction, so as to counter the forces exerted radially when the pipe is under pressure. These high tenacity yarns are joined together by weft yarns, which have properties of mechanical resistance to transverse traction to ensure cohesion of the ribbon in the transverse direction and to exhibit dimensional stability of the width when the ribbon is used under voltage. It is thus known to use weft threads based on fiberglass, which are coated with a fuse material, ensuring a certain blocking of the warp threads after activation of this heat-fusible material. This solution, although satisfactory, has certain drawbacks, since the wires of

-2 glass employees have limited resistance to abrasion, and a certain amount of moisture that can be detrimental under certain conditions.

In addition, the use of these weft threads based on glass threads can cause dimensional deformation of the tape when the latter is under longitudinal tension. Indeed, the weft yarns woven with the high tenacity warp yarns have a certain amount of mist due to their alternating passage above and below the warp yarns. However, when a longitudinal traction is exerted on the ribbon, the warp threads tend to approach the plane of the ribbon, with an increase in the embuvage of the weft threads. Since in a “ribbon” weaving, the weft threads are continuous, and surround the warp threads located at the edge, the increase in the weft in the weft inevitably causes a reduction in the width of the ribbon when the latter is put under longitudinal tension. The fact that the ribbon has a variation in width as a function of the longitudinal tension which is applied to it is inconvenient for the adjustment of the wrapping machines and in particular for the determination of the precise pitch of the helix which the reinforcing ribbon must form. .

Statement of invention

There is therefore a need to produce ribbons which have high dimensional stability, in particular in width, whatever the level of longitudinal tension applied, and this while retaining a very high resistance to elongation of the ribbon.

To do this, the Applicant has designed a textile ribbon, intended for wrapping high pressure fluid transport pipes, which is formed by weaving warp threads of a first type having a high tenacity, with threads weft. This ribbon is characterized in that it comprises in the warp direction of the threads of a second type, having a title less than the title of the high tenacity threads of the first type. As a complement, the wires of the first type have a

- Nearly zero buckling, that is to say less than 1%, while the warp threads of the second type have a higher buckling, typically greater than 1.5% or 2%. Thus, a basting of the son of the second type has a bogging greater than the bogging of warp son of the first type, typically at least one and a half times, or even two or three times.

In other words, the invention consists in producing the ribbon by combining in warp different yarns, namely on the one hand the high tenacity yarns, which ensure the mechanical properties of tensile strength and which remain almost straight after weaving, with threads which undergo a relatively strong deformation during weaving. In this way, when the ribbon is placed under longitudinal tension, the wires of the first type, which are already rectilinear, cause the ribbon to not lengthen, and there is therefore no phenomenon of transverse necking. In other words, the ribbon includes in a chain complementary threads which deform during weaving, so as to bond the weft threads with the ply of main threads, which ensure the mechanical properties of the ribbon. These complementary threads therefore deform more easily than the weft threads, and than the other warp threads.

Different variants can be declined, both with regard to the threads used, in particular the materials and the geometric properties of the threads, as well as the weaving conditions. Thus, it is possible to use yarns of the first and second types which are based on identical materials. In this case, the threads of the second type will be woven by setting the warp tension to a sufficiently low value, and clearly lower than that applied to the threads of the first type, so that the threads of the second type will take the strongest deformations, in undergoing the displacements imposed by the positioning of the weft yarns, and thus have a strong shrinking.

-4II is also possible to use threads based on different materials, to minimize the impact in terms of weight, or cost of threads of the second type in the overall ribbon.

Thus, for certain applications, it is preferable to choose wires of the second type which have a lower tenacity and / or greater elongation than the wires of the first type, to facilitate their elongation and their deformation. This choice of more deformable materials can be supplemented by the use of different warp tensions during weaving, to allow the threads of the second type to deform around the weft threads during weaving.

Thus, in practice, the yarns of the first type can be made of a material chosen from the group comprising aramid, carbon, and in general materials of very high toughness. In addition, the yarns of the second type are preferably made of a material chosen from the group comprising polyester, and polypropylene.

In practice, performance terminalies are obtained when the wires of the second type have a title less than 10 times, preferably less than 20 times the title of the wires of the first type.

Depending on the desired mechanical properties, and the range of longitudinal tension applied, the proportion between the wires of the first and second type can be adapted. It is thus possible to provide for an alternation of wires of the second and first type all the wires, or every two or three wires of the first type.

In addition, the weft threads can also have a count of two or even preferably 10 times lower than the count of the threads of the first type.

In an advantageous embodiment, the weft threads can include a heat-fusible sheath, making it possible to ensure the fixing of the ribbon after exposure to a heat source.

Brief description of the drawings.

The manner of carrying out the invention, as well as the advantages which result therefrom, will emerge clearly from the description of the embodiment which follows, with the support of the appended figures in which:

- Figure 1 is a summary perspective view of a textile tape according to the invention;

- Figures 2 and 3 are cross-sectional views, along the plane in ΙΙ-ΙΓ of Figure 1, in which the tape is respectively without and under longitudinal tension;

- Figure 4 is a longitudinal sectional view along the plane in IV-IV 'of Figure 1.

Of course, the elements represented appear were schematically and simplified, and their dimensions and proportions can deviate from reality, and have been given only to facilitate understanding of the invention.

detailed description

As illustrated in FIG. 1, the ribbon 1 has warped high tenacity yarns 2, which may for example be based on aramid, and have a titer of the order of a few tens to a few hundred tex. These ribbons 1 also include wires 3 made of a material of lesser toughness, with greater elongation, and of a title much lower than the wires 2 of the first type. These yarns of the second type 3 can for example be based on polyester or the like, with therefore a toughness of the order of 1000 MPa and 12% elongation at break, to be compared with the tenacity of the yarns of the first type, of around 3000 MPa and 3% elongation at break. The sons of the second type 3 have a clearly marked

-6 weaker than the son of the first type 2, typically of the order of a few tex to a few tens of tex.

In the illustrated form, the wires of the second type 3 are arranged in proportion to one wire every two wires of the first type 2. Of course, the invention covers other configurations, in which the proportion between the wires of the first type 2 and of the second type 3 are different. The distribution of these two types of wire can be regular, even irregular for certain applications.

These warp threads 2,3 are held relative to each other by means of a weft thread 5 which is woven with the warp threads, according to a plain weave in the form shown in FIG. 1. In this case, the warp thread weft 5 which is continuous passes from one selvedge 6 to the other 7 of the ribbon 1. In the “ribbon” weaving mode, the weft thread 5 is introduced by a selvedge 6, so as to form a loop 14 at the level from the opposite edge 7. Alternatively, at each insertion, all the warp threads of the first type 2 are raised while all the warp threads of the second type 3 are held, lowered, and vice versa. At the edge 7 where the loops 14 of the weft thread are located, a filler thread 17 comes to block these loops 14 by a chain

In practice, this weft thread 5 can be made with materials of low toughness, such as polyester, and have a titer of the order of a few tex to a few tens of tex. It can advantageously be coated with a heat-fusible material, to allow the fixing of the warp threads 2,3 and thus facilitate the handling of the ribbon.

This tape has the advantage of undergoing a weak, if not zero, necking when it is subjected to a longitudinal tension, that is to say in the warp direction. Indeed, during the weaving of the ribbon, the warp threads of the first type remain substantially rectilinear, and the presence of the weft thread 5 causes, as illustrated in FIGS. 2

-7and 3, the deformation of the warp threads of the second type. These yarns of the second type are found either above the yarns of the first type, when the weft yarn passes over the sheet of warp yarns of the first type, as illustrated in FIG. 2, or below, when the yarn of weft is located under the ply of threads, as illustrated in FIG. 3. Consequently, the warp threads of the second type have a strong embuvage, which is observed in FIG. 4, while the warp threads of the first type show little or no embovering. It follows that when the ribbon is subjected to a longitudinal tension, the warp threads of the first type do not deform, and do not modify the configuration of the weft thread 5, phenomenon which would be observed with a weaving of identical chain in material and in weaving tension.

Good results have thus been obtained by using, as yarn of the first type, aramid-based yarns, with a count of 330 tex, having a tenacity before twisting of the order of 3000 MPa, and twisted, with a number of turns. of 60 turns per meter. In this example, the yarns of the second type are polyester-based yarns, with a count of the order of 14 tex, while the weft yarns are also polyester-based yarns, with a count of the order of 28 tex. The measurement of the embuvage is made by comparison of the length of a sample of ribbon, and the length of a thread of this sample, extracted from the fabric and made rectilinear. The embuvage is expressed as a percentage of the length of the thread compared to the length of the fabric sample. In the example illustrated, the bending of the wires (2) of the first type is 0.7%, while it is 2% for the wires (4) of the second type, with a ration of the bogs of the 2.8.

Of course, the choices of different materials and their title can be adapted according to the dimensions of the tape, its mechanical performance, and the maximum necking rate tolerated under nominal longitudinal tension.

The ribbon according to the invention therefore has the advantage of having dimensional stability which makes it particularly compatible with the wrapping processes for manufacturing high pressure fluid lines, which require high precision.

Claims (9)

1 / Textile tape (1), designed for wrapping high pressure fluid transport pipes, formed by weaving warp threads of a first type (2) having a high tenacity, with weft threads ( 5), characterized in that it comprises, in the warp direction, threads of a second type (3) having a title lower than the title of the threads of the first type (2), and in which the threads of the second type ( 2) have a higher misting than the misting of warp threads of the first type (3). 2 / textile tape (1) according to claim 1, characterized in that the warp son of the second type (2) have a boiling at least one and a half times, preferably two times greater than the boiling of warp son of the first type (3). 3 / tape according to claim 1, characterized in that the son of the second type (3) have a lower tenacity and / or greater elongation to the son of the first type (2). 4 / ribbon according to claim 1, characterized in that the son of the first type (2) are made of a material selected from the group comprising aramid, carbon. 5 / tape according to claim 1, characterized in that the son of the second type (3) are made of a material selected from the group comprising polyester, polypropylene. 6 / Tape according to claim 1, characterized in that the son of the second type (3) have a titer ten times lower, preferably twenty times lower than the title of the son of the first type (2). -107 / Ribbon according to claim 1, characterized in that it comprises an alternation of wires of the second type and of wires of the first type. 5 8 / ribbon according to claim 1, characterized in that it comprises a wire of the second type every two son of the first type. 9 / ribbon according to claim 1, characterized in that it comprises a wire of the second type every three son of the first type. 10 / Tape according to claim 1, characterized in that it comprises weft threads (5) having a count less than two, preferably ten times lower than the count of threads of the first type (2). 15 11 / ribbon according to claim 1, characterized in that all or part of the weft son have a hot melt sheath.