EP4087970A1

EP4087970A1 - Single-layer multi-strand cable having improved energy at break and an improved total elongation

Info

Publication number: EP4087970A1
Application number: EP20845790.3A
Authority: EP
Inventors: Gaël PATAUT; Henri Barguet; Lucas LAUBY; Olivier REIX
Original assignee: Compagnie Generale des Etablissements Michelin SCA
Current assignee: Compagnie Generale des Etablissements Michelin SCA
Priority date: 2020-01-07
Filing date: 2020-12-18
Publication date: 2022-11-16
Anticipated expiration: 2040-12-18
Also published as: JP2023509076A; EP4087970B1; CN114929963A; US20230349097A1; KR20220116335A; WO2021140287A1; CN114929963B

Abstract

The invention relates to a multi-strand cable (50) having a 1xN structure comprising a single layer (52) of N strands (54) that are helically wound about a main axis (A), each strand (54) consisting of a layer (56) of metal wires (F1) and comprising M>1 metal wires that are helically wound about an axis (B). The cable (50) has a total elongation At > 8.10%, and the energy-at-break index Er = rAt of the cable (50) is defined as Er = ∫ ^AT σ(Αί) x dAi, where σ(Αί) is the tensile stress in MPa measured at the elongation Ai, and dAi is the elongation such that Er is strictly greater than 52 MJ/m³.

Description

Energy-enhanced breaking single-layer multi-strand rope with improved total elongation

The invention relates to cables, a reinforced product and a tire comprising these cables.

[002] From the state of the art, in particular from document WO2016 / 131862, a tire for a civil engineering vehicle with a radial carcass reinforcement is known comprising a tread, two inextensible beads, two sidewalls connecting the beads to the tread. bearing and a crown reinforcement, disposed circumferentially between the carcass reinforcement and the tread. This crown reinforcement comprises several plies reinforced by reinforcing elements such as metal cables, the cables of a ply being embedded in an elastomeric matrix of the ply.

[003] The crown frame comprises a working frame, a protective frame and possibly other frames, for example a hoop frame.

[004] The protective frame comprises one or more protective plies comprising several wire protective reinforcement elements. Each wire protection reinforcement element is a cable having a 1xN structure. The cable comprises a single layer of N = 4 strands wound in a helix at a pitch p3 = 20 mm. Each strand comprises, on the one hand, an internal layer of M = 3 internal wires wound in a helix at a pitch p1 = 6.7 mm and an external layer of V = 8 external wires wound in a helix around the internal layer at a pitch p2 = 10 mm. Each inner and outer wire has a diameter equal to 0.35 mm and the total elongation of the cable is 6%.

[005] On the one hand, when the tire passes over obstacles, for example in the form of pebbles, these obstacles risk puncturing the tire until it reaches the crown reinforcement. These perforations allow the entry of corrosive agents into the crown reinforcement of the tire and reduce its life.

[006] On the other hand, it has been observed that the cables of the protective plies can exhibit breaks following relatively large deformations and forces exerted on the cable, in particular when the tire passes over obstacles.

[007] The aim of the invention is a cable making it possible to reduce, or even eliminate, the number of breaks and the number of perforations.

[008] To this end, the invention relates to a multi-strand cable having a 1xN structure comprising a single layer of N strands wound helically around a main axis (A), each strand having a layer of metal wires and comprising M> 1 metallic wires wound in a helix around an axis (B), in which:

-the cable has a total elongation At> 8, 10% determined by standard ASTM D2969-04 of 2014; and rat

-the energy indicator at break Er of the cable defined by Er = J ₀ s (ί) x dAi with s (ί) being the tensile stress in MPa measured at the elongation Ai and dAi being the elongation such that Er is strictly greater than 52 MJ / m ³ .

[009] Thanks to the relatively high total elongation and the relatively high energy at break of the cable, the cable according to the invention makes it possible to reduce perforations and therefore to extend the life of the tire. Indeed, the inventors behind the invention have discovered that a cable less rigid than that of the prior art performs better against obstacles. The inventors have found that it is more effective to match the obstacle with a cable having less rigidity rather than attempting to stiffen and strengthen the cables as much as possible to oppose the deformations imposed by the obstacles as is. generally taught in the state of the art. By hugging the obstacles, we reduce the effort against the obstacles and therefore the risk of puncturing the tire. This stiffness reduction effect is illustrated in Figure 7 where under stress the cable according to the invention exhibits good deformability under low load thanks to the radial play of the wires.

[010] Thanks to the relatively high total elongation, the relatively high energy at break of the cable, the cable according to the invention also makes it possible to reduce the number of breaks. Indeed, the inventors at the origin of the invention have discovered that the determining criterion for reducing cable breaks was not only the breaking force as is widely taught in the state of the art but the indicator. energy at break represented in the present application by the area under the stress curve as a function of the elongation as illustrated in part in FIG. 4. Indeed, the cables of the prior art have either a force at relatively high break but a relatively low elongation at break, i.e. a relatively high elongation at break but a relatively low tensile strength. In either case, prior art cables break under a relatively low energy-to-break indicator. The cable according to the invention, due to its relatively high total elongation, has a necessarily relatively high elongation at break. Synergistically, the relatively low modulus makes it possible to delay elongation at break due to a slope of the stress-elongation curve in the elastic range which is relatively low. Finally and above all, the inventors have discovered that the increase in the total elongation made it possible, as demonstrated by the comparative tests below, on the one hand, to postpone the elongation at break and therefore to increase the stress. , which makes it possible to increase the energy at break.

[011] Any interval of values designated by the expression “between a and b” represents the domain of values ranging from more than a to less than b (that is to say limits a and b excluded) while any interval of values designated by the expression "from a to b" means the domain of values going from the terminal "a" to the terminal "b", that is to say including the strict limits "a" and "b".

[012] The total elongation At, a quantity well known to those skilled in the art, is determined for example by applying the ASTM D2969-04 standard of 2014 to a cable tested so as to obtain a stress-elongation curve. The At on the curve obtained is deduced as the elongation, in%, corresponding to the projection on the axis of the elongations of the breaking point of the cable on the stress-elongation curve, i.e. the point at which the load increases to a maximum value of stress and then decreases sharply after failure. When the decrease in relation to the stress exceeds a certain threshold, it means that the break of the cable has taken place.

[013] The energy indicator at break Er of the cable is determined by calculating the area under the stress curve rAt as a function of the elongation by the relation Er = J ₀ s (ί) x dAi. This indicator of energy at rupture represents a volume density of energy in MJ / m ³ . The rectangles method is conventionally used to achieve this area: the tensile stress sigma (Ai) being expressed in MPa measured at the elongation Ai expressed in% without unit; for i = 0: Ai = 0 = A0 = 0% elongation and for i = t: Ai = t = At: elongation at total break of the cable. The energy indicator at rupture Er is thus the sum of (1/2 (o (Ai) + o (Ai + 1)) x (Ai + 1 - Ai) for i ranging from 0 to t. , the sampling of the rectangles is defined such that the widths defined by (Ai + 1 - Ai) are substantially equal to 0.025%, i.e. 4 rectangles for 0.1% elongation as shown in figure 4.

[014] In the invention, the cable comprises a single layer of N strands, that is to say it comprises an assembly consisting of a layer of strands, neither more nor less, that is to say, say the assembly has one layer of strands, not zero, not two, but only one.

[015] Advantageously, the direction of winding of each strand is opposite to the direction of winding of the cable.

[016] The direction of winding of a layer of strands is understood to mean the direction formed by the strands relative to the axis of the cable. The direction of winding is commonly designated by the letter either Z or S.

[017] The winding directions of the strands are determined in accordance with ASTM D2969-04 of 2014.

[018] The cable according to the invention is a single helix. By definition, a single helix cable is a cable in which the axis of each strand of the layer describes a single helix around a main axis, unlike a double helix cable in which the axis of each strand describes a first helix around the axis of the cable and a second helix around a helix described by the axis of the cable. In other words, when the cable extends in a substantially rectilinear direction, the cable comprises a single layer of strands wound together. helical, each strand of the layer describing a helical-shaped path around a main axis substantially parallel to the substantially rectilinear direction so that, in a section plane substantially perpendicular to the main axis, the distance between the center of each strand of the layer and the main axis is substantially constant and equal for all strands of the layer. On the contrary, when a double helix cable extends in a substantially rectilinear direction, the distance between the center of each strand of the layer and the substantially rectilinear direction is different for all the strands of the layer.

[019] In the same way as described above for the cable, each strand according to the invention is a single helix. By definition, a single helix strand is a strand in which the axis of each metallic wire element of the layer describes a single helix, unlike a double helix strand in which the axis of each metallic wire element describes a first helix. around the axis of the strand and a second helix around a helix described by the axis of the strand. In other words, when the strand extends in a substantially rectilinear direction, the strand comprises a single layer of metallic wire elements wound together in a helix, each metallic wire element of the layer describing a trajectory in the form of a helix around a main axis substantially parallel to the substantially rectilinear direction so that, in a section plane substantially perpendicular to the main axis, the distance between the center of each metallic wire element of the layer and the main axis is substantially constant and equal for all metallic wire elements of the layer. On the contrary, when a double helix strand extends in a substantially rectilinear direction, the distance between the center of each metallic wire element of the layer and the substantially rectilinear direction is different for all the metallic wire elements of the layer. [020] The cable according to the invention does not have a central metal core. We also speak of cable of structure 1xN in which N is the number of strands or even of cable with open structure (“open-cord” in English). In the cable according to the invention defined above, the internal vault is empty and therefore devoid of any filling material, in particular devoid of any elastomeric composition. This is referred to as a cable devoid of filler material.

[021] By wire element is meant an element extending longitudinally along a main axis and having a section perpendicular to the main axis, the largest dimension G of which is relatively small compared to the dimension L along the main axis. By relatively small is meant that L / G is greater than or equal to 100, preferably greater than or equal to 1000. This definition covers both wire elements of circular section and wire elements of non-circular section, for example of polygonal section. or oblong. Very preferably, each metallic wire element has a circular section.

[022] The term "metallic" is understood to mean by definition a wire element consisting mainly of (that is to say for more than 50% of its mass) or entirely (for 100% of its mass) of a metallic material. Each metallic wire element is preferably made of steel, more preferably of pearlitic or ferrito-pearlitic carbon steel, commonly called by those skilled in the art carbon steel, or even stainless steel (by definition, steel comprising at least 10.5% chrome).

[023] Preferably, the metal wires and the strands do not undergo preformation. In other words, the cable is obtained by a process devoid of individual preforming steps of each of the metallic wire elements and of each of the strands.

[024] Advantageously, the total elongation At> 8.30% and preferably At> 8.50%.

[025] Advantageously, the total elongation At <20.00% and preferably At <16.00%. [026] Advantageously, the energy at break indicator Er of the cable (50) is greater than or equal to 55 MJ / m ³ .

[027] Preferably, the energy at break indicator Er of the cable (50) is less than or equal to 200 MJ / m ³ and preferably less than or equal to 150 MJ / m ³ .

[028] Preferably, the cable has a structural elongation As determined by standard ASTM D2969-04 of 2014 such as As> 4.30%, preferably As> 4.50% and more preferably As> 4.60%.

[029] Preferably, the cable has a structural elongation As determined by standard ASTM D2969-04 of 2014 such that As <10.0% and preferably As <9.50%.

[030] The structural elongation As, a quantity well known to those skilled in the art, is determined, for example, by applying the standard ASTM D2969-04 of 2014 to a cable tested so as to obtain a force-elongation curve. The As on the curve obtained is deduced as the elongation, in%, corresponding to the projection on the axis of the elongation of the intersection between the tangent to the structural part of the force-elongation curve and the tangent to the part elasticity of the force-elongation curve. As a reminder, a force-elongation curve comprises, by moving towards increasing elongations, a structural part, an elastic part and a plastic part. The structural part corresponds to the structural elongation As resulting from the aeration of the cable, that is to say the space vacant between the different metal strands constituting the cable. The elastic part corresponds to an elastic elongation resulting from the construction of the cable, in particular the angles of the different layers and the diameters of the strands. The plastic part corresponds to the plastic elongation resulting from the plasticity (irreversible deformation beyond the elastic limit) of one or more metallic wire elements of the strands.

[031] Preferably, the cable has a secant modulus E1 ranging from 3.0 to 10.0 GPa and preferably ranging from 3.5 to 8.5 GPa.

[032] The cable according to the invention can thus have a significant deformation at low force and a first low rigidity. [033] The secant modulus E1 is the slope of the straight line connecting the origin of the stress-elongation curve obtained under the conditions of standard ASTM D 885 / D 885M - 10a of 2014 to the point of abscissa 1% of this same curve.

[034] Preferably, the cable has a tangent modulus E2 ranging from 50 to 180 GPa and preferably from 55 to 150 GPa.

[035] Thus the cable according to the invention has a minimum rigidity to allow the absorption or transmission of force.

[036] The tangent modulus E2 is calculated as follows on the stress-elongation curve obtained under the conditions of standard ASTM D 885 / D 885M - 10a of 2014: E2 corresponds to the maximum tangent modulus of the cable on the force-elongation curve.

[037] The invention also relates to a cable extracted from a polymer matrix, the extracted cable having a 1xN structure comprising a single layer of N strands wound helically around a main axis (A), each strand being at a distance. layer of metallic wires and comprising M> 1 metallic wires wound in a helix around an axis (B), in which:

-the extracted cable (50 ’) has a total elongation At’> 5.00% determined by the ASTM D2969-04 standard of 2014,

- the energy at break indicator Er 'of the extracted cable (50') defined by Er ' x dAi with s (4ί) being the tensile stress in MPa measured at the elongation Ai and dAi being the elongation such that Er 'is strictly greater than 35 MJ / m ³ .

[038] Preferably, the polymeric matrix is an elastomeric matrix.

[039] The polymeric matrix, preferably elastomeric, is based on a polymeric composition, preferably elastomeric.

[040] By polymeric matrix is meant a matrix comprising at least one polymer. The polymeric matrix is thus based on a polymeric composition.

[041] By elastomeric matrix is meant a matrix comprising at least one elastomer. The preferred elastomeric matrix is thus based on the elastomeric composition.

[042] By the expression "based on", it should be understood that the composition comprises the mixture and / or the in situ reaction product of the various constituents used, some of these constituents being able to react and / or being intended to react between them, at least partially, during the various phases of manufacture of the composition; the composition may thus be in the fully or partially crosslinked state or in the non-crosslinked state.

[043] By polymeric composition is meant that the composition comprises at least one polymer. Preferably, such a polymer can be a thermoplastic, for example a polyester or a polyamide, a thermosetting polymer, an elastomer, for example natural rubber, a thermoplastic elastomer or a mixture of these polymers. [044] By elastomeric composition is meant that the composition comprises at least one elastomer and at least one other component. Preferably, the composition comprising at least one elastomer and at least one other component comprises an elastomer, a crosslinking system and a filler. The compositions which can be used for these webs are conventional compositions for calendering wire reinforcing elements and comprise a diene elastomer, for example natural rubber, a reinforcing filler, for example carbon black and / or silica, a system of crosslinking, for example a vulcanization system, preferably comprising sulfur, stearic acid and zinc oxide, and optionally a vulcanization accelerator and / or retarder and / or various additives. The adhesion between the metal wires and the matrix in which they are embedded is ensured for example by a metal coating, for example a layer of brass. [045] The values of the characteristics described in the present application for the extracted cord are measured on or determined from cables extracted from a polymeric matrix, in particular elastomeric, for example from a tire. Thus, for example on a tire, the strip of material is removed radially outside the cable to be extracted so as to see the cable to be extracted radially flush with the polymer matrix. This withdrawal can be done by shelling using pliers and knives or by planing. Then, the end of the cable to be extracted is released by means of a knife. Then, the cable is pulled so as to extract it from the matrix by applying a relatively small angle so as not to plasticize the cable to be extracted. The extracted cables are then cleaned carefully, for example by means of a knife, so as to detach the remains of the polymer matrix attached locally to the cable and taking care not to degrade the surface of the metal wires.

[046] Preferably, the total elongation At ’is such that At’> 5.20%.

[047] Preferably, the energy at break indicator Er 'of the cable (50) is greater than or equal to 40 MJ / m ³ .

[048] The advantageous characteristics described below apply equally to the cable as defined above and to the extracted cable.

[049] Advantageously, the cable is such that the strands define an internal arch of the cable of diameter Dv, each strand having a diameter Dt and a radius of helix curvature Rt defined by Rt = Pe / (nx Sin (2ae)) with Pe the pitch of each strand expressed in millimeters and ae the helix angle of each strand (54), in which Dv, Dt and Rt being expressed in millimeters: 25 <Rt / Dt <180 and 0.10 <Dv / Dt <0.50.

[050] The cable according to the invention exhibits excellent longitudinal compressibility and, all other things being equal, a relatively small diameter.

[051] On the one hand, the inventors behind the invention hypothesize that, due to a sufficiently large radius of curvature Rt compared to the diameter Dt of each strand, the cable is sufficiently ventilated, thus reducing the risk of buckling, due to the relatively large distance of each strand from the longitudinal axis of the cable, distance allowing the strands to accommodate, through their helix, relatively high longitudinal compressive deformations . On the contrary, the radius of curvature Rt of each strand of the cable of the prior art being relatively small compared to the diameter Dt, the metallic wire elements are closer to the longitudinal axis of the cable and can accommodate, by virtue of their propeller, longitudinal compressive deformations much less than the cable according to the invention.

[052] On the other hand, for a radius of curvature Rt of each strand that is too high, the cable according to the invention would have insufficient longitudinal compressive stiffness to provide a reinforcing role, for example for tires.

[053] In addition, for an internal vault diameter Dv that is too high, the cable would have, relative to the diameter of the strands, a diameter that is too high.

[054] The values of the characteristics Dt, Dv and Rt as well as the other characteristics described below are measured on or determined from the cables either directly after manufacture, that is to say before any embedding step in a die. elastomeric, or extracted from an elastomeric matrix, for example from a tire, and then having undergone a cleaning step during which any elastomeric matrix is removed from the cable, in particular any material present inside the cable. To ensure an original condition, the adhesive interface between each metallic wire element and the elastomeric matrix must be removed, for example by an electrochemical process in a sodium carbonate bath. The effects associated with the shaping step of the tire manufacturing process described below, in particular the elongation of the cables, are canceled out by the extraction of the ply and the cable which, during extraction, take up substantially their characteristics before the conformation stage.

[055] The arch of the cable according to the invention is delimited by the strands and corresponds to the volume delimited by a theoretical circle, on the one hand, radially inside each strand and, on the other hand, tangent to each strand. The diameter of this theoretical circle is equal to the diameter of the vault Dv.

[056] The helix angle of each strand ae is a quantity well known to those skilled in the art and can be determined by the following calculation: tan ae = 2cp x Re / Pe, formula in which Pe is the pitch expressed in millimeters in which each strand is wound, Re is the helix radius of each strand expressed in millimeters, and tan denotes the tangent function ae is expressed in degrees.

[057] The helix diameter De, expressed in millimeters, is calculated according to the relation De = Pe x Tan (ae) / p in which Pe is the pitch expressed in millimeters at which each strand is wound, ae is the angle d helix of each strand determined above and Tan the tangent function. The helix diameter De corresponds to the diameter of the theoretical circle passing through the centers of the strands of the layer in a plane perpendicular to the main axis of the cable.

[058] The arch diameter Dv, expressed in millimeters, is calculated using the relationship Dv = De- Dt in which Dt is the diameter of each strand and De is the helix diameter, both expressed in millimeters.

[059] The radius of curvature Rt, expressed in millimeters, is calculated according to the relation Rt = Pe / (nx Sin (2ae)) in which Pe is the pitch expressed in millimeters of each strand, ae is the helix angle of each strand and Sin the sine function.

[060] It will be recalled that the pitch at which each strand is wound is the length traveled by this wire element, measured parallel to the axis of the cable in which it is located, at the end of which strand having this pitch makes a complete revolution around said cable axis.

[061] Advantageously, the cable is such that the metal wire elements define an internal arch of the strand of diameter Dvt, each metal wire element having a diameter Df and a radius of helix curvature Rf defined by Rf = P / (nx Sin (2a)) with P the pitch of each metallic wire element expressed in millimeters and at the helix angle of each metallic wire element (F1), Dvt, Dfet Rf being expressed in millimeters, the cable satisfying the following relations: 9 <Rf / Df <30, and 1.30 <Dvt / Df <4.50.

[062] The arch of each strand is delimited by metal wires and corresponds to the volume delimited by a theoretical circle, on the one hand, radially inside each wire element and, on the other hand, tangent to each metal wire element. The diameter of this theoretical circle is equal to the diameter of the vault Dvt.

[063] The helix angle of each metallic wire element a is a quantity well known to those skilled in the art and can be determined by the following calculation: tan a = 2cp x R / P, formula in which P is the pitch expressed in millimeters in which each strand is wound, R is the helix radius of each strand expressed in millimeters, and tan denotes the tangent function a is expressed in degrees.

[064] The helix diameter Dh, expressed in millimeters, is calculated according to the relationship Dh = P x Tan (a) / p in which P is the pitch expressed in millimeters at which each wire element is wound, a is the helix angle of each metallic wire element determined above and Tan the tangent function. The helix diameter Dh corresponds to the diameter of the theoretical circle passing through the centers of the metallic wire elements of the layer in a plane perpendicular to the main axis of the cable.

[065] The arch diameter of the strand Dvt, expressed in millimeters, is calculated using the relationship Dvt = Dh-Df where Df is the diameter of each wire element and Dh is the helix diameter, both expressed in millimeters.

[066] The radius of curvature Rf, expressed in millimeters, is calculated according to the relation Rf = P / (nx Sin (2a)) in which P is the pitch expressed in millimeters of each wire element metallic, a is the helix angle of each metallic wire element and Sin the sine function. [067] It is recalled that the pitch at which each metallic wire element is wound is the length traveled by this wire element, measured parallel to the axis of the cable in which it is located, at the end of which the wire element having this pitch performs one complete turn around said axis of the cable.

[068] The optional characteristics described below may be combined with one another to the extent that such combinations are technically compatible. [069] In an advantageous embodiment, all the metallic wire elements have the same diameter Df.

[070] The subject of the invention is also a process for manufacturing a cable comprising:

- a manufacturing step of N strands by:

- a step of providing a transient assembly comprising a layer consisting of M ’> 1 metal wires wound helically around a transient core;

- a step of separation of the transitional assembly between:

- a first fractional assembly comprising a layer consisting of M1 '> 1 metal wire (s) wound in a helix, the M1' metal wire (s) coming from the layer made up of M '> 1 metal wires of the transient assembly,

- a second split assembly comprising a layer made up of M2 ’> 1 metallic wires wound in a helix, the M2’ metallic wires coming from the layer made up of M ’> 1 metallic wires of the transient assembly,

- the transient core or one or more sets comprising the transient core,

a step of reassembling the first split assembly with the second split assembly to form a strand with one layer of metal wires and comprising M> 1 metal wires;

- a step of assembling the N strands by cabling to form the cable.

[071] Each strand is manufactured in accordance with a method and by implementing an installation described in documents WO2016083265 and WO2016083267. Such a method implementing a fractionation step is to be distinguished from a conventional cabling method comprising a single assembly step in which the metallic wire elements are wound in a helix, the assembly step being preceded by a step of individual preformation of each metallic wire element in order in particular to increase the value of the structural elongation. Such methods and installations are described in documents EP0548539, EP1000194, EP0622489, WO2012055677, JP2007092259,

W02007128335, JPH06346386 or EP0143767. During these processes, in order to obtain the highest possible structural elongation, the metal monofilaments are individually preformed. However, this step of individual preformation of the metal monofilaments, which requires a particular installation, on the one hand, makes the process relatively not very productive compared to a process without an individual preforming step without however making it possible to achieve high structural elongations and, on the other hand, deteriorates the metal monofilaments thus preformed due to friction with the preforming tools. Such an alteration creates the initiation of breaks at the surface of the metal monofilaments and is therefore harmful for the endurance of the metal monofilaments, in particular for their compression endurance. The absence or presence of such preformation marks can be observed under an electron microscope at the end of the manufacturing process, or even more simply, by knowing the manufacturing process of the cable.

[072] Due to the method used, each metallic wire element of the cable is devoid of preformation mark. Such preforming marks include in particular flats. The preformation marks also include cracks extending in section planes substantially perpendicular to the main axis along which each wire element extends. Such cracks extend, in a section plane substantially perpendicular to the main axis, from a radially outer surface of each wire member radially inwardly of each wire member. As described above, such cracks are initiated by mechanical preforming tools due to bending forces, that is to say perpendicular to the main axis of each metallic wire element, which makes them very harmful for endurance. Conversely, in the method described in WO2016083265 and WO2016083267 in which the metallic wire elements are preformed collectively and simultaneously on a transient core, the preformation forces are exerted in torsion and therefore not perpendicular to the main axis of each wire element. metallic. Any cracks created do not extend radially from the radially outer surface of each wire element radially towards the interior of each wire element but along the radially outer surface of each wire element which makes them little harmful to endurance.

[073] Advantageously, the cable has a diameter D such that D <6.00 mm and preferably D <5.00 mm.

[074] The apparent diameter or diameter, denoted D, is measured by wedging the cable between two perfectly straight bars of length 200 mm and by measuring the spacing in which the cable is embedded by means of the comparator described below, one can cite by example the model JD50 / 25 of the brand KAEFER allowing to reach a precision of 1/100 of a millimeter, equipped with type a key, and having a contact pressure close to 0.6N. The measurement protocol consists of three repetitions of a series of three measurements (carried out perpendicular to the axis of the cable and under zero tension)

[075] In one embodiment, each metallic wire element comprises a single metallic monofilament. Here, each metallic wire element is advantageously constituted of a metallic monofilament. In a variant of this embodiment, the metallic monofilament is directly coated with a layer of a metallic coating comprising copper, zinc, tin, cobalt or an alloy of these metals, for example brass or the bronze. In this variant, each metallic wire element then consists of the metallic monofilament, for example steel, forming a core, directly coated with the metallic coating layer.

[076] In this embodiment, each elementary metallic monofilament is, as described above, preferably made of steel, and has a mechanical strength ranging from 1000 MPa to 5000 MPa. Such mechanical strengths correspond to the steel grades commonly encountered in the field of tires, namely, the grades NT (Normal Tensile), HT (High Tensile), ST (Super Tensile), SHT (Super High Tensile), UT ( Ultra Tensile), UHT (Ultra High Tensile) and MT (Mega Tensile), the use of high mechanical strengths possibly allowing an improved reinforcement of the matrix in which the cable is intended to be embedded and a lightening of the matrix thus reinforced.

[077] Advantageously, the layer consists of N strands wound in a helix, N ranges from 2 to 6.

[078] The method of assembling the N strands is implemented by cabling. By cabling is meant that the strands do not undergo torsion about their own axis, due to synchronous rotation before and after the assembly point. The main advantage of this is to increase the ductility of the cables but also to obtain a greater breaking force than those of the opencord strands alone.

[079] In a first embodiment allowing partial reassembly of the M 'wire elements, the separation step and the reassembly step are performed so that M1 ’+ M2’ <M ’.

[080] In a second embodiment allowing complete reassembly of the M 'wire elements, the separation step and the reassembly step are performed so that M1 ’+ M2’ = M ’.

[081] The advantageous characteristics described below apply equally to the method of the first and second modes as defined above.

[082] Preferably, M = MT + M2 ’ranges from 3 to 18 and preferably from 4 to 15.

[083] Advantageously, in order to facilitate the exit of the transient core in the embodiments in which the transient core is separated into two parts each going with the first and second split assemblies:

- M1 ’= 1, 2 or 3 and M2’ = 1, 2 or 3 in cases where M ’= 4 or M’ = 5 and

- MT <0.75 x M ’in cases where M’> 6.

- M2 '<0.75 x M' in cases where M '> 6. [084] In order to further facilitate the exit of the transient core in embodiments in which the transient core is separated into two parts each going with the first and second assemblies in cases where M '> 6, M1'<0, 70 x M 'and M2'<0.70 x

M ’.

[085] Very preferably, the step of providing the transient assembly comprises an assembly step by twisting the M ’> 1 wire elements wound helically around the transient core.

[086] Advantageously, the step of providing the transient assembly includes a step of balancing the transient assembly. Thus, the balancing step being carried out on the transient assembly comprising the M 'metal wire elements and the transient core, the balancing step is implicitly carried out upstream of the separation step between the first and second assemblies. fractional. One avoids having to manage the residual torsion imposed during the assembly step of the transient assembly during the path of the various assemblies downstream of the assembly step, in particular in the guide means, for example the pulleys.

[087] Advantageously, the method comprises a step of balancing the final assembly downstream of the reassembly step.

[088] Advantageously, the method comprises a step of maintaining the rotation of the final assembly around its direction of travel. This rotational maintenance step is performed downstream of the transient assembly separation step and upstream of the final assembly balancing step.

[089] Preferably, the method is devoid of individual preforming steps of each of the metallic wire elements. In the methods of the state of the art using an individual preforming step of each of the metallic wire elements, the latter are imposed a shape by preforming tools, for example rollers, these tools creating defects on the surface of the metal. wire elements of metal. These defects significantly reduce the endurance of metallic wire elements and therefore of the final assembly.

[090] Very preferably, the transient core is a metallic wire element. In a preferred embodiment, the transient core is a metallic monofilament. Thus, the diameter of the space between the metallic wire elements and therefore the geometric characteristics of the final assembly is very precisely controlled, unlike a transient core made of a textile material, for example polymeric material, the compressibility of which can generate variations in the geometric characteristics of the final assembly.

[091] In other equally advantageous embodiments, the transient core is a textile filament element. Such a textile filament element comprises at least one multifilament textile strand or, in a variant, consists of a textile monofilament. Filaments textiles which can be used are chosen from polyesters, polyketones, aliphatic or aromatic polyamides and mixtures of textile filaments of these materials. Thus, the risks of breakage of the transient core generated by the friction of the metallic wire elements on the transient core as well as by the torsions imposed on the transient core are reduced.

[092] REINFORCED PRODUCT ACCORDING TO THE INVENTION

[093] The subject of the invention is also a reinforced product comprising a polymer matrix and at least one extracted cable as defined above.

[094] Advantageously, the reinforced product comprises one or more cables according to the invention embedded in the polymer matrix, and in the case of several cables, the cables are arranged side by side in a main direction.

[095] PNEUMATICS ACCORDING TO THE INVENTION

[096] A subject of the invention is also a tire comprising at least one extracted cable as defined above or a reinforced product as defined above.

[097] Preferably, the tire comprises a carcass reinforcement anchored in two beads and surmounted radially by a crown reinforcement itself surmounted by a tread, the crown reinforcement being joined to said beads by two sidewalls and comprising at least one cable as defined above.

[098] In a preferred embodiment, the crown frame comprises a protective frame and a working frame, the working frame comprising at least one cable as defined above, the protective frame being radially interposed between the tread and the working reinforcement.

[099] The cable is most particularly intended for industrial vehicles chosen from heavy vehicles such as "Heavy goods" - ie, metro, bus, road transport vehicles (trucks, tractors, trailers), off-road vehicles - , agricultural or civil engineering machinery, other transport or handling vehicles.

[0100] Preferably, the tire is for a vehicle of the civil engineering type. Thus, the tire has a dimension in which the diameter, in inches, of the seat of the rim on which the tire is intended to be mounted is greater than or equal to 30 inches. [0101] The invention also relates to a rubber article comprising an assembly according to the invention, or an impregnated assembly according to the invention. By rubber article is meant any type of rubber article such as a balloon, a non-pneumatic object such as a non-pneumatic tire, a conveyor belt or a track.

[0102] The invention will be better understood on reading the examples which follow, given solely by way of non-limiting examples and made with reference to the drawings in which:

- Figure 1 is a sectional view perpendicular to the circumferential direction of a tire according to the invention;

FIG. 2 is a detailed view of zone II of FIG. 1;

- Figure 3 is a sectional view of a reinforced product according to the invention;

- Figure 4 illustrates part of the stress-elongation curve of a cable (50) according to the invention;

- Figure 5 is a schematic sectional view perpendicular to the cable axis (assumed rectilinear and at rest) of a cable (50) according to a first embodiment of the invention;

- Figure 6 is a view similar to that of Figure 5 of a cable (60) according to a second embodiment of the invention;

- Figure 7 is a schematic representation of the effect of the deformability of the cable (50) of Figure 5 under low tensile load due to the radial play of the wires; and Figures 8 and 9 are schematic representations of the method according to the invention for manufacturing the cable (50) of Figure 5.

[0103] EXAMPLE OF A TIRE ACCORDING TO THE INVENTION

[0104] In Figures 1 and 2, there is shown a reference X, Y, Z corresponding to the usual respectively axial (X), radial (Y) and circumferential (Z) orientations of a tire.

[0105] The “median circumferential plane” M of the tire is the plane which is normal to the axis of rotation of the tire and which is located equidistant from the annular reinforcing structures of each bead.

[0106] There is shown in Figures 1 and 2 a tire according to the invention and designated by the general reference P.

The tire P is for a heavy vehicle of the civil engineering type, for example of the “dumper” type. Thus, the tire P has a dimension of type 53 / 80R63.

[0108] The tire P comprises a crown 12 reinforced by a crown reinforcement 14, two sidewalls 16 and two beads 18, each of these beads 18 being reinforced with an annular structure, here a bead wire 20. The crown reinforcement 14 is radially surmounted by a tread 22 and joined to the beads 18 by the sidewalls 16. A carcass reinforcement 24 is anchored in the two beads 18, and is here wound around the two bead wires 20 and comprises an upturn 26 disposed towards the exterior of the tire 20 which is shown here mounted on a rim 28. The carcass reinforcement 24 is surmounted radially by the crown reinforcement 14.

The carcass reinforcement 24 comprises at least one carcass ply 30 reinforced by radial carcass cables (not shown). The carcass cables are arranged substantially parallel to each other and extend from one bead 18 to the other so as to form an angle of between 80 ° and 90 ° with the median circumferential plane M (plane perpendicular to the axis of rotation of the tire which is located midway between the two beads 18 and goes through the middle of the crown frame 14).

[0110] The tire P also comprises a sealing ply 32 made of an elastomer (commonly called an inner rubber) which defines the radially internal face 34 of the tire P and which is intended to protect the carcass ply 30 from the diffusion of air. 'air coming from the space inside the tire P.

[0111] The crown reinforcement 14 comprises, radially from the outside towards the inside of the tire P, a protective reinforcement 36 arranged radially inside the tread 22, a working reinforcement 38 arranged radially on the inside. inside the protective frame 36 and an additional frame 40 arranged radially inside the working frame 38. The protective frame 36 is thus radially interposed between the tread 22 and the reinforcement. work 38. The working frame 38 is radially interposed between the protective frame 36 and the additional frame 40.

The protective frame 36 comprises first and second protective plies 42, 44 comprising protective metal cables, the first ply 42 being arranged radially inside the second ply 44. Optionally, the cables protective metals form an angle at least equal to 10 °, preferably ranging from 10 ° to 35 ° and preferably from 15 ° to 30 ° with the circumferential direction Z of the tire.

The working frame 38 comprises first and second working plies 46, 48, the first ply 46 being arranged radially inside the second ply 48. Each ply 46, 48 comprises at least one cable 50. Optionally, the metal working cables 50 are crossed from one working ply to the other and form an angle at most equal to 60 °, preferably ranging from 15 ° to 40 ° with the circumferential direction Z of the tire.

[0114] The additional reinforcement 40, also called a limiter block, the function of which is to partially take up the mechanical inflation stresses, comprises, for example and in a manner known per se, additional metallic reinforcing elements, for example such as described in FR 2 419 181 or FR 2 419 182 forming an angle at most equal to 10 °, preferably ranging from 5 ° to 10 ° with the circumferential direction Z of the tire P.

EXAMPLE OF A REINFORCED PRODUCT ACCORDING TO THE INVENTION FIG. 3 shows a reinforced product according to the invention and designated by the general reference R. The reinforced product R comprises at least one cable 50 ', in l 'species several cables 50', embedded in the polymer matrix Ma.

FIG. 3 shows the polymer matrix Ma, the cables 50 'in an X, Y, Z frame in which the Y direction is the radial direction and the X and Z directions are the axial and circumferential directions. In Figure 3, the reinforced product R comprises several cables 50 arranged side by side in the main direction X and extending parallel to each other within the reinforced product R and collectively embedded in the matrix polymeric Ma.

Here, the polymer matrix Ma is an elastomeric matrix based on an elastomeric composition.

[0118] CABLE ACCORDING TO A FIRST EMBODIMENT OF THE INVENTION [0119] FIG. 5 shows the cable 50 according to a first embodiment of the invention.

[0120] Each protective reinforcing element 43, 45 and each hooping reinforcing element 53, 55 is formed, after extraction of the tire 10, by an extracted cable 50 ′ as described below. The cable 50 is obtained by embedding in a polymeric matrix, in this case in a polymeric matrix respectively forming each polymeric matrix of each protective ply 42, 44 and of each hooping layer 52, 54 in which are respectively embedded the elements of protection 43, 45 and hoop reinforcement 53, 55. [0121] The cable 50 and the extracted cable 50 ′ are single-layer metal.

[0122] The cable 50 or the cable 50 'comprises a 1xN structural layer comprising a single layer 52 of N = 3 strands 54 helically wound around a main axis (A), each strand 54 being at a layer 56 of metallic wires F1 and comprising M> 1 metallic wires wound in a helix around an axis (B), with here M = 5.

As described above, the value At is determined by plotting a stress-elongation curve of the cable 50 by applying the standard ASTM D2969-04 of 2014.

[0124] The cable 50 has a total elongation At> 8.10%, preferably At> 8.30% and more preferably At> 8.50% and the total elongation At <20.00% and preferably At < 16.00%. here At = 13.4%.

As described above, from this stress-elongation curve, the area under this curve is deduced therefrom. Figure 4 shows the method of rectangles to determine the energy at break indicator of cable 50. rAt

[0126] The energy indicator at rupture Er of the cable 50 is such that = Er = J ₀ s (Aί) x dAi which is substantially equal to åo¾, ^4% l / 2 (s (Aί) + s (Aί + 1)) x 0.025% = 89 MJ / m ³ which is strictly greater than 52 MJ / m ³ , preferably greater than or equal to 55 MJ / m ³ and less than or equal to 200 MJ / m ³ and preferably less than or equal to 150 MJ / m ³ .

The cable 50 has a structural elongation As such that As> 4.30%, preferably As> 4.50% and more preferably As> 4.60% and such that As <10.0% and preferably As <9.50%. Here As = 9.3%.

The cable 50 has a secant modulus E1 ranging from 3.0 to 10.0 GPa and preferably ranging from 3.5 to 8.5 GPa. Here E1 = 4.0 GPa

The cable 50 has a tangent modulus E2 ranging from 50 to 180 GPa and preferably from 55 to 150 GPa. Here E2 = 73 GPa. [0130] The extracted cord 50 'has a total elongation At'> 5.00% and preferably At '> 5.20%. Here At '= 10.0%.

The energy indicator at rupture Er 'of the extracted cable 50' is such that Er '= x dAi which is substantially equal to l / 2 (s (Aί) + s (Aί + 1)) x 0.025% = 82 MJ / m ³ which is strictly greater than 35 MJ / m ³ , preferably greater than or equal to 40 MJ / m ³ . [0132] The strands 54 define an internal vault 59 of the cables 50; 50 'of diameter Dv, each strand 54 having a diameter Dt and a helix radius of curvature Rt defined by Rt = Pe / (T x Sin (2ae)) = 80 / (px sin (2 x 5.3 x TT / 180) = 138 mm.

[0133] Rt / Dt = 138 / 2.03 = 68 <180 and 68> 25.

[0134] Dv / Dt = 0.32 / 2.03 = 0.16 <0.50 and 0.16> 0.10.

The metallic wire elements F1 of each strand 52 define an internal arch 58 of the strand 52 of diameter Dvt, each metallic wire element F1 has a diameter Df and a helix radius of curvature Rf defined by Rf = P / (nx Sin (2a)) = 10.4 / (px sin (2 x 25.8 xp / 180) = 4.2 mm.

[0136] Rf / Df = 4.2 / 0.46 = 9 <30.

[0137] Dvt / Df = 1.12 / 0.46 = 2.46 <4.50 and 2.46> 1.30.

[0138] PROCESS FOR MANUFACTURING THE CABLE ACCORDING TO THE INVENTION

We will now describe an example of a method for manufacturing the multi-strand cable 50 as shown in FIGS. 8 and 9.

[0140] First, we unwind the wire elements F1 and the transient core 16 from the power supply.

Then, the method comprises a step 100 of supplying the transient assembly 22 comprising on the one hand an assembly step by twisting the M 'metallic wire elements F1 into a single layer of M' metallic wire elements F1 around of the transient core 16 and on the other hand, a step of balancing the transient assembly 22 carried out by means of a twister.

The method comprises a step 110 of separating the transient assembly 22 between the first fractional assembly 25, the second fractional assembly 27 and the transient core 16 or one or more assemblies comprising the transient core 16, here the transient core 16 .

[0143] Downstream of the supply means 11, the step 110 of separating the transient assembly 22 between the first split assembly 25, the second split assembly 27 and the transient core 16 comprises a step 120 of separating the assembly transient 22 between the precursor assembly, the second fractional assembly 27 and finally the transient core 16.

[0144] Downstream of the separation step 122, the separation step 120 of the assembly transient between the precursor assembly and the fractionated assembly comprises a step 124 of separation of the fractionated assembly between the second fractionated assembly 27 and the transient core 16. Here, the separation step 124 comprises a step of fractionation of the whole split into the second split assembly 27, the transient core 16 and the complementary set.

[0145] Downstream of the supply step 100, the step 110 of separating the transient assembly between the first fractional assembly 25, the second fractional assembly 27 and the transient core 16 comprises a step 130 of separating the precursor assembly between the first fractional assembly 25 and the complementary assembly.

[0146] Downstream of the separation steps 110, 120, 124 and 130, the method comprises a step 140 of reassembling the first fractional assembly 25 with the second fractional assembly 27 to form the strand 54. In this embodiment, the reassembly step 140 is a reassembly step of the first fractional assembly 25 with the second fractional assembly 27 to form the strand 54 and comprising M> 1 metal wires F 1, with M ranging from 3 to 18 and preferably from 4 to 15, here M = 5.

In this embodiment, the supply step 100, the separation step 110 and the reassembly step 140 are carried out so that all the M 'metallic wire elements F1 have the same diameter Df, are wound. helical with the same pitch P and have the same radius of curvature of helix Rf described above.

[0148] In this embodiment allowing partial reassembly of the M 'wire elements, the separation step 110 and the reassembly step 140 are performed so that M1 ’+ M2’ <M ’. Here M1 ’= 1 and M2’ = 4, M1 ’+ M2’ = 5 <8. Finally, note that M1 ’<0.70 x M’ = 0.70 x 8 = 5.6 and M2 ’<0.70 x M’ = 0.70 x 8 = 5.6.

[0149] A final balancing step is carried out.

Finally, the strand 54 is stored on a storage reel. N strands 54 are made in the same way.

Concerning the transient core 16, the method comprises a step of recycling the transient core 16. During this recycling step, the transient core 16 is recovered downstream from the separation step 110, here downstream from the step. separation 124, and the transient core 16 recovered previously is introduced upstream of the assembly step. This recycling step is continuous.

[0152] It will be noted that the method thus described does not have any individual preforming steps for each of the metallic wire elements F1.

[0153] A step 300 of assembling the N strands 54 is carried out by cabling to form the cable 50. Here N = 3.

[0154] It will be noted that the method thus described does not have any individual preforming steps for each of the strands 54. [0155] CABLE ACCORDING TO A SECOND EMBODIMENT OF THE INVENTION [0156] FIG. 6 shows the cable 60 according to a second embodiment of the invention.

Unlike the first embodiment described above, the cable 60 according to the second embodiment is such that N = 4.

The characteristics for the various cables 50, 50 ', 60, 60', 51, 52, 53, 53 ', 54 according to the invention and for the cables have been summarized in Tables 1, 2 and 3 below. state of the art cables EDT1, EDT1 ', EDT2 and EDT2'.

[0159] COMPARATIVE TESTS

[0160] Evaluation of the total elongation and of the energy indicator at break of the cables [0161] The stress-elongation curves of the cables were plotted by applying the standard ASTM D2969-04 of 2014 and the value was determined. total elongation and the energy at break indicator for the various cables 50, 50 ', 60, 60', 51, 52, 53, 53 ', 54 according to the invention and for the cables of the state of the art EDT1, EDT1 ', EDT2 and EDT2'.

In Table 3, the mention “NA” means that the quantity has not been measured. [0163] [Table 1]

[0164] [Table 2]

[0165] [Table 3]

[0166] Tables 1, 2 and 3 show that the cables 50, 50 ', 60, 60', 51, 52, 53, 53 ', 54 according to the invention have both an energy at break indicator improved and have better deformability compared to cables of the state of the art EDT 1, EDT 1 ', EDT2 and EDT2'.

[0167] Thus, the cables according to the invention make it possible to solve the problems mentioned in the preamble.

[0168] The invention is not limited to the embodiments described above.

Claims

1. Multi-strand cable (50) having a 1xN structure comprising a single layer (52) of N strands (54) wound helically around a main axis (A), each strand (54) having a single layer (56). ) of metal wires (F1) and comprising M> 1 metal wires wound in a helix around an axis (B), characterized in that:

- the cable (50) has a total elongation At> 8.10% determined by standard ASTM D2969-04 of 2014; and rAt

- the energy indicator at break Er of the cable (50) defined by Er = J ₀ s (ί) x dAi with s (ί) being the tensile stress in MPa measured at elongation Ai and dAi being the elongation such that Er is strictly greater than 52 MJ / m ³ .

2. Cable (50) according to the preceding claim, wherein the total elongation At> 8.30% and preferably At> 8.50%.

3. Cable (50) according to any one of the preceding claims, in which the energy at break indicator Er of the cable (50) is greater than or equal to 55 MJ / m ³ .

4. Cable (50) according to any one of the preceding claims, having a structural elongation As determined by standard ASTM D2969-04 of 2014 such as As> 4.30%, preferably As> 4.50% and more preferably As> 4.60%.

5. Cable (50) according to any one of the preceding claims, having a secant modulus E1 ranging from 3.0 to 10.0 GPa and preferably ranging from 3.5 to 8.5 GPa.

6. Cable (50) according to any one of the preceding claims, having a tangent modulus E2 ranging from 50 to 180 GPa and preferably from 55 to 150 GPa.

7. Cable extracted (50 ') from a polymer matrix, the cable extracted (50') having a 1xN structure comprising a single layer (52) of N strands (54) wound in a helix around a main axis (A), each strand (54) having a layer (56) of metal wires (F1) and comprising M> 1 metal wires wound in a helix around an axis (B), characterized in that:

- the extracted cable (50 ’) has a total elongation At’> 5.00% determined by standard ASTM D2969-04 of 2014,

- the energy at break indicator Er 'of the extracted cable (50') defined by Er ' s (Aί) x dAi with s (4ί) being the tensile stress in MPa measured at the elongation Ai and dAi being the elongation such that Er 'is strictly greater than 35 MJ / m ³ .

8. Extracted cable (50 ’) according to the preceding claim, wherein the total elongation At’ is such that At ’> 5.20%.

9. Extracted cable (50 ') according to claim 7 or 8, wherein the energy at break indicator Er' of the cable (50) is greater than or equal to 40 MJ / m ^3.

10. Cable (50; 50 ') according to any one of the preceding claims, wherein the strands (54) define an internal arch (59) of the cable (50; 50') of diameter Dv, each strand (54) having a diameter Dt and a helix radius of curvature Rt defined by Rt = Pe / (nx Sin (2ae)) with Pe the pitch of each strand expressed in millimeters and ae the helix angle of each strand (54), Dv, Dt and Rt being expressed in millimeters, the cable (50; 50 ') satisfying the following relationships: 25 <Rt / Dt <180 and 0.10 <Dv / Dt <0.50.

11. Cable (50; 50 ') according to any one of the preceding claims, wherein the metal wire elements (F1) defining an internal arch (58) of the strand (52) of diameter Dvt, each metal wire element (F1) having a diameter Df and a helix radius of curvature Rf defined by Rf = P / (nx Sin (2a)) with P the pitch of each metallic wire element expressed in millimeters and at the helix angle of each wire element metallic (F1), Dvt, Df and Rf being expressed in millimeters, the cable satisfying the following relationships: 9 <Rf / Df <30, and 1, 30 <Dvt / Df <4.50.

12. A method of manufacturing a cable (50) according to any one of claims 1 to 6 and 10 and 11, characterized in that it comprises:

-a manufacturing step (200) of N strands (54) by:

- a step (100) of providing a transient assembly (22) comprising a layer consisting of M ’> 1 metal wires (F1) wound helically around a transient core (16);

- a step (110) of separating the transient assembly (22) between:

- a first fractional assembly (25) comprising a layer (26) consisting of M1 '> 1 metal wire (s) (F1) wound in a helix, the M1' metal wire (s) ) (F1) coming from the layer made up of M '> 1 metal wires (F1) of the transient assembly (22),

- a second split assembly (27) comprising a layer (28) made up of M2 '> 1 metal wires (F1) wound in a helix, the M2' metal wires (F1) coming from the layer made up of M '> 1 metal wires (F1) of the transient assembly (22),

- the transient core (16) or one or more sets (83) comprising the transient core

(16),

- a step (140) of reassembling the first fractional assembly (25) with the second fractional assembly (27) to form a strand (52) with a layer of metal wires (F1) and comprising M> 1 metal wires (F1);

- an assembly step (300) of the N strands (54) by wiring to form the cable (50).

13. Method according to the preceding claim, in which M ranges from 3 to 18 and preferably from 4 to 15.

14. Reinforced product (R), characterized in that it comprises a polymer matrix (Ma) and at least one extracted cable (50 ’) according to any one of claims 7 to 11.

15. Tire (P), characterized in that it comprises at least one extracted cable (50 ') according to any one of claims 7 to 11 or a reinforced product according to claim 14.