System for the continuous manufacturing of an elongate composite part having a circular cross-section

Abstract

A system (100) for the continuous manufacturing of an elongate composite part comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material. The first radiation device (117) comprises a tube which is made of translucent and oxygen-permeable material and through which the impregnated monofilament (E1) travels.

Description

[0001] DESCRIPTION

[0002] TITLE: Installation for the continuous production of an elongated composite element with a circular section

[0003] The present invention relates to the field of reinforcements based on composite materials.

[0004] More particularly, the present invention relates to the continuous manufacture of elongated composite materials produced by impregnation of a polymerizable composition of multifilament fibers.

[0005] More particularly, the present invention relates to an installation for manufacturing composites in the form of single strands comprising continuous, unidirectional multifilament fibers embedded in a polymerizable resin.

[0006] The present invention relates more particularly, but not exclusively, to the manufacture of single strands of glass resin composite, with the acronym “CVR”, having high mechanical properties.

[0007] Such elongated composite materials can be used in the form of composite reinforcements which can be used, in particular, for the reinforcement of semi-finished products or finished rubber articles such as vehicle tires, for example of the pneumatic or non-pneumatic type, or in concrete reinforcement applications.

[0008] Generally, with reference to figure 1, a device 1 for manufacturing a single strand of glass-resin composite comprises a reel 10 containing glass fibers 11 in the form of multifilaments and continuously unwound by driving along the arrow F by a driving means (not shown), so as to produce a rectilinear arrangement 12 of these fibers 11.

[0009] The arrangement 12 then passes through a vacuum chamber 13 arranged between an inlet nozzle 13a and a separation nozzle 13b and an impregnation chamber 14 downstream of the separation nozzle 13b and filled with impregnation composition 15 based on a curable resin. The device 1 further comprises a calibration die

[0010] 16 at the outlet of the impregnation chamber 14 so as to obtain a single strand 17 and a radiation device 18 comprising, for example, a protection tube 18a through which the composite single strand circulates

[0011] 17 and a plurality of UV irradiators 18b in line in order to obtain a polymerized monostrand 19.

[0012] However, such a sealed tube quickly becomes clogged with the polymerizable material.

[0013] We know the document EP 1 174 250 - A l which describes a process for the continuous manufacture of CVR monostrands comprising the following steps:

[0014] - making an arrangement of glass fibers and driving this arrangement in a direction of advancement;

[0015] - degas the fiber arrangement by the action of vacuum in a vacuum chamber;

[0016] - at the outlet of the vacuum chamber, after degassing, pass through an impregnation chamber filled with resin so as to impregnate said arrangement of fibers with a resin in the liquid state to obtain an impregnation containing the fibers and the resin;

[0017] - passing said impregnated material through a calibration die having a predefined surface section and shape, to impose a single-strand shape on it; and

[0018] - downstream of the calibration line, in an irradiation chamber, stabilize, solidify the single strand by photopolymerization of the resin in a UV and / or IR radiation device.

[0019] Traditionally, known composite monostrands have a circular cross-section and are composed of continuous glass fibers impregnated with a polymerizable material, preferably photo-polymerizable.

[0020] However, in practice, the final geometry of the composite monofilament section is not perfectly circular, but rather slightly elliptical. This elliptical shape is a consequence of current manufacturing facilities and processes in which the composite monofilament emerges from the sizing die coated with a polymerizable material that is still in a liquid state before final polymerization. The composite monofilament therefore still has the possibility of modifying its geometry before final polymerization sets its shape.

[0021] In some applications, a slight deformation of the elliptical geometry does not pose any problems, for example in concrete reinforcement applications. However, in other applications, particularly in vehicle tires, it is necessary, before introducing the composite monofilament into the tire, to pass it through circular shaping dies. This can cause problems with jamming or even breakage of the composite monofilament if its cross-section is not sufficiently circular.

[0022] Composite monofilaments with circular cross-section have the same physical properties in all directions, whereas those with elliptical cross-section are anisotropic.

[0023] Thus, there is a need to address the above-mentioned drawbacks.

[0024] The invention aims to improve the circularity of the section of a composite monostrand, while avoiding fouling of the tube of the first polymerization die and maintaining a high production speed, between 80m / min and 200m / min, preferably between 100m / min and 120m / min.

[0025] Furthermore, the present invention aims to adapt easily to existing composite monostrand manufacturing installations.

[0026] The present invention relates to an installation for the continuous manufacture of an elongated composite element comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material, the installation comprising, in the direction of advance of the bundle of multifilament fibers:

[0027] - a feeding device configured to form a bundle of multifilament fibers;

[0028] - a degassing chamber for the multifilament fiber bundle;

[0029] - an impregnation chamber filled with a composition based on a polymerizable material and configured to impregnate said degassed multifilament fiber bundle with said composition and form an impregnated single strand, said impregnation chamber being located downstream of the degassing chamber in the direction of advancement of the multifilament fiber bundle; and

[0030] - a first radiation device through which the single strand impregnated with polymerizable material circulates and configured to carry out a partial polymerization of the impregnated single strand to form a pre-polymerized single strand; and at least

[0031] - a second radiation device, separate and distinct from the first radiation device configured to form a final composite monostrand, and

[0032] - a translational drive device configured to drive the bundle of multifilament fibers in translation and to apply tension to said bundle of multifilament fibers.

[0033] In other words, the second radiation device is configured to perform a final polymerization of the pre-polymerized monostrand.

[0034] The first radiation device comprises a guide tube made of translucent and oxygen-permeable material through which the single strand impregnated with polymerizable material circulates.

[0035] By "translucent" we mean a body capable of transmitting light in a diffuse manner through which the object is visible, at least in a blurred manner, or even clearly for a transparent body.

[0036] The outer surface of the single strand impregnated with polymerizable material entering the first radiation device is in contact with the inner surface of the guide tube.

[0037] Thanks to the oxygen-permeable guide tube, the photopolymerization of the polymerizable material is inhibited, so that the outer surface of the impregnated monostrand is still liquid.

[0038] Indeed, in the presence of oxygen, the free radicals which initiate the polymerization of the polymerizable material are inhibited or greatly slowed down. Thanks to the guide tube, it is thus possible to efficiently polymerize the core of the single strand impregnated with polymerizable material, while keeping the outer surface of said single strand impregnated with polymerizable material liquid in contact with the inner surface of the guide tube.

[0039] Thanks to its liquid outer surface, the pre-polymerized single strand thus obtained can be easily extracted from the guide tube of the first radiation device.

[0040] By "partial polymerization or pre-polymerization" is meant that the degree of polymerization of the radiation-impregnated multifilament fiber bundle has reached between 35% and 65% of complete polymerization.

[0041] As a non-limiting example, the degree of polymerization can be evaluated using a “DSC” type measuring instrument, an acronym for “Differential Scanning Calorimetry” in English terms.

[0042] The pre-polymerization step makes it possible to obtain a pre-polymerized, non-sticky single strand, capable of no longer deforming in the free state while being malleable to be deformed under mechanical stress.

[0043] The so-called “complete” or “final” polymerization of the composite is obtained when the degree of polymerization of the polymerizable material is close to 100%, preferably greater than or equal to 95% of the total polymerization.

[0044] Thanks to the guide tube, a pre-polymerized single strand of circular cross-section is obtained, without the need to mechanically deform the cross-section of the single strand by using an additional mechanical shaping device.

[0045] The circularity of the section of a composite monostrand is therefore improved, while maintaining a high production speed, between 80m / min and 200m / min, preferably between 100m / min and 120m / min.

[0046] The second radiation device is here a final radiation device. Alternatively, one could provide for adding a third radiation light source arranged downstream of the final radiation device.

[0047] By "elongated composite element" is meant a very long composite element comprising a bundle of multifilament fibers embedded in a composition based on a polymerizable material, which is manufactured continuously from one or more supply reels of multifilament fibers to form a bundle which is driven in translation to successively impregnate its fibers with polymerizable material and polymerize the material as the bundle moves.

[0048] By “multifilament fiber” is meant a fiber which comprises several elementary filaments arranged side by side to form a bundle whose elementary fibers are unidirectional while being substantially parallel to each other.

[0049] Multifilament fibers can be chosen from the group consisting of glass, carbon, silica, ceramic, flax, hemp, basalt, cellulose, etc. fibers. These multifilament fibers are used to produce elongated composites made by impregnating the multifilament fibers with a polymerizable composition.

[0050] The polymerizable material may be of the thermosetting type, preferably thermocrosslinkable, preferably of the vinylester type. By polymerizable material is meant a material comprising, by weight, more than 50%, preferably more than 75%, of organic matter and even more preferably more than 90% of organic matter, preferably more than 95%.

[0051] Thus, this material may be a thermopolymerizable polymeric material, for example based on unsaturated polyester, polyepoxide, phenolic derivative, or aminoplast. Preferably, the polymerizable material is crosslinked.

[0052] For example, the polymerizable material is a resin that can be crosslinked by ionizing radiation, and the final polymerization can be easily triggered and controlled by means of an ionizing treatment, for example of the UV type.

[0053] The glass transition temperature Tg of the polymerizable material is preferably greater than or equal to 130°C, for example greater than 170°C, preferably greater than or equal to 180°C.

[0054] For example, the final composite element is a single strand comprising multifilament fibers embedded in a polymerizable material, such as a thermosetting resin.

[0055] The final composite monofilament can take the form of a cylindrical monofilament with a diameter between 0.2mm and 2.5mm, preferably between 0.7mm and 1.1mm.

[0056] The elementary filaments, for example, each have an average diameter of between 5pm and 30pm.

[0057] The drive device is, for example, of the type comprising a motorized traction drum allowing the composite element to be wound around its axis or comprising two motorized drums facing each other, being spaced apart by a corresponding distance at least equal to the thickness of the composite element and which rotate in opposite directions to drive the final composite element, by friction, in a translational movement, making it pass into the space located between the two drums.

[0058] Advantageously, the guide tube is made of thermoplastic polymer, such as polytetrafluoroethylene (PTFE) known, for example, under the registered trademark “Teflon™”, preferably amorphous fluoropolymer, with the acronym “AF”.

[0059] Preferably, the guide tube is made of an amorphous fluoropolymer having a glass transition temperature of 240°C.

[0060] Preferably, the guide tube comprises a tensile modulus of 1.5 GPa and a tensile stress between 24.5 MPa and 28.3 MPa at 23°C and between 2.4 MPa and 6 MPa at 220°C.

[0061] Preferably, the guide tube has an optical transition greater than or equal to 95% with a refractive index of 1.29.

[0062] For example, the guide tube comprises a wall with a thickness of between 0.1 mm and 0.8 mm. Advantageously, the first radiation device comprises a device for fixing the guide tube and the guide tube extends over the entire length of the first radiation device between an input base and a stiffening base of the fixing device.

[0063] The fixing device further comprises, for example, a plurality of holding fins, for example in the form of thin plates, arranged parallel to one another along the axis of advancement and axially separated from one another by a distance, for example constant, each holding fin comprising a central orifice for the passage of the guide tube.

[0064] For example, the fixing device further comprises at least one stiffening rod secured to the stiffening base and in which each holding fin comprises an end orifice for the passage of the stiffening rod.

[0065] According to a variant, the fixing device comprises two stiffening rods each extending along a longitudinal axis parallel to the axis of advancement and parallel to each other and in which each holding fin comprises two end orifices for the passage of a stiffening rod.

[0066] Advantageously, the first radiation device is delimited by a rigid input plate provided with a through orifice and a rigid output plate, also provided with a through orifice located axially opposite the orifice of the input plate, and in which the input base of the fixing device is integral with said input plate.

[0067] The input base is, for example, mounted in the through-hole of the input plate of the first radiation device and comprises a first passage for the impregnated single-strand and a second passage, coaxial with the first passage, for fixing the guide tube.

[0068] The first passage advantageously has a diameter smaller than the diameter of the second passage and in particular the diameter of the tube. Thus, the first passage forms a seal for the first radiation device.

[0069] For example, the inlet plate comprises a through hole for supplying oxygen inside the first radiation device and the outlet plate comprises a through hole for supplying nitrogen or nitrogen inside the first radiation device and a through hole for discharging gaseous fluids to the outside.

[0070] The single strand impregnated with polymerizable material is introduced into the first radiation device by passing it through the orifice of the inlet plate and exiting through the through orifice of the outlet plate.

[0071] According to one embodiment, the installation comprises a heating device associated with the impregnation chamber and configured to heat the polymerizable material present in said impregnation chamber to a temperature between 50°C and 95°C, preferably 60°C to 80°C. Alternatively, it could be provided that the installation does not comprise such a heating device.

[0072] According to one embodiment, the first radiation device comprises a first light source which combines ultraviolet radiation, acronym UV, and infrared radiation, acronym IR.

[0073] The exposure time of the impregnated single strand to the first light source with combined ultraviolet / infrared radiation is between 0.1 s and 1.5 s, preferably between 0.4 and 0.7 s.

[0074] The power of the first light source with combined UV and infrared radiation is between 2kW and 14kW, preferably between 4kW and 7kW.

[0075] According to one embodiment, the first light source comprises a plurality of light-emitting diodes configured to emit only monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm, preferably between 365nm and 405nm.

[0076] According to another embodiment, the first light source comprises a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet (UV) radiation, infrared radiation, and visible light.

[0077] According to one embodiment, the second radiation device comprises a second light source with ultraviolet and infrared radiation or infrared radiation alone to complete the polymerization of the pre-polymerized single strand.

[0078] The duration of exposure of the pre-polymerized monostrand to the second light source combining ultraviolet and infrared rays is between 1 s and 6 s, preferably between 1.5 s and 3 s.

[0079] The power of the second UV and infrared light source is between 100kW and 60kW, preferably between 20kW and 40kW

[0080] According to a variant, the second light source comprises a plurality of light-emitting diodes, acronym LED, preferably directed radially towards the pre-polymerized single strand, the available wavelengths of which are between 200nm and 405nm, preferably between 365nm and 405nm. In this case, the LEDs are combined with infrared radiation.

[0081] According to another variant, the second light source could comprise a plurality of mercury vapor lamps, the exposure time of the pre-polymerized single strand of which is between 1 s and 4 s, preferably between 1.5 s and 2 s, at a power of between 100kW and 60kW, preferably between 20kW and 40kW.

[0082] Alternatively, the second light source could include a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet (UV) radiation, infrared radiation, and visible light. The mercury vapor lamps may be combined with infrared radiation with an infrared radiation wavelength between 1 pm and 3 pm.

[0083] According to yet another variant, it could be provided that the second radiation device comprises a light source with infrared radiation alone configured to emit only infrared radiation, with a wavelength between 1 pm and 3 pm. In this case, the duration of exposure of the pre-polymerized monostrand to the second light source combining infrared radiation alone is between 2 s and 8 s, preferably between 3 s and 4 s and the power of this second infrared light source is between 1 0 kW and 60 kW, preferably between 20 kW and 40 kW.

[0084] Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example, and made with reference to the appended drawings in which:

[0085] [Fig. l] very schematically represents an installation for manufacturing a composite element according to the state of the art;

[0086] [Fig.2] very schematically represents an installation for manufacturing a composite element according to one embodiment of the invention;

[0087] [Fig.3] and [Fig.4] represent partial sectional views of details of the installation of Figure 2; and

[0088] [Fig.5] illustrates a perspective view of the tube of the first radiation device of Figure 2 secured to a mounting bracket.

[0089] Figure 2 schematically illustrates an installation 100 for manufacturing a very long, elongated EF composite element.

[0090] By "elongated composite element" is meant a composite element of great length comprising a bundle of multifilament fibers embedded in a composition based on a polymerizable material, which is manufactured continuously from one or more supply reels of multifilament fibers Fi_0 to form a bundle which is driven in translation along the arrow F to successively carry out the impregnation of its fibers with polymerizable material and the polymerization of the material as the bundle moves. By "multifilament fiber" is meant a fiber which comprises several elementary filaments Fi arranged side by side to form a bundle whose elementary fibers are unidirectional while being substantially parallel to each other.

[0091] Multifilament fibers can be chosen from the group consisting of glass, carbon, silica, ceramic, flax, hemp, basalt, cell fibers, etc. These multifilament fibers are used to produce elongated composites made by impregnating the multifilament fibers with a polymerizable composition.

[0092] The polymerizable material may be of the thermosetting type, preferably thermocrosslinkable, preferably of the vinylester type. By polymerizable material is meant a material comprising, by weight, more than 50%, preferably more than 75%, of organic matter, and even more preferably more than 90% of organic matter, or even more than 95%.

[0093] Thus, this material may be a thermopolymerizable polymeric material, for example based on unsaturated polyester, polyepoxide, phenolic derivative, or aminoplast. Preferably, the polymerizable material is crosslinked.

[0094] For example, the polymerizable material is a resin that can be crosslinked by ionizing radiation, and the final polymerization can be easily triggered and controlled by means of an ionizing treatment, for example of the UV type.

[0095] The glass transition temperature Tg of the polymerizable material is preferably greater than or equal to 130°C, for example greater than 170°C, preferably greater than or equal to 180°C.

[0096] In the example illustrated in the figures, the composite element EF is a single strand comprising multifilament fibers embedded in a polymerizable material, such as a thermosetting resin.

[0097] The EF composite monofilament can take the form of a cylindrical monofilament with a diameter between 0.2mm and 2.5mm, preferably between 0.7mm and 1.1mm.

[0098] The elementary filaments each have, for example, an average diameter of between 5 pm and 30 pm. As illustrated in FIG. 2, the manufacturing installation 100 comprises, in the direction of advancement of the bundle of multifilament fibers according to the arrow F:

[0099] - a supply device 1 1 1 comprising here one or more reels 1 12 for supplying elementary filaments Fi_0 to form a bundle of multifilament fibers E0,

[0100] - a vacuum chamber 1 13 or degassing chamber arranged between an inlet nozzle 1 13a and an outlet nozzle 1 13b;

[0101] - an impregnation chamber 114 downstream of the vacuum chamber 113 and in particular of the outlet pipe 113b and filled with an impregnation composition 115 based on a polymerizable material;

[0102] - a calibration die 1 16 at the outlet of the impregnation chamber 1 14 so as to obtain a single strand E l impregnated with polymerizable material;

[0103] - a first radiation device 117 through which circulates the single strand E1 impregnated with polymerizable material and configured to carry out a partial or intermediate polymerization of said impregnated single strand E1 and form a pre-polymerized single strand E2;

[0104] - a second radiation device 1 18 or final radiation device, distinct from the first radiation device 1 17, through which the pre-polymerized monostrand E2 circulates and configured to carry out a final polymerization to form a final composite monostrand EF; and

[0105] - a translational drive device D according to arrow F configured to drive the bundle of multifilament fibers in translation to successively carry out degassing, impregnation of its fibers with polymerizable material and polymerization of the material as the bundle moves.

[0106] The vacuum chamber 113, the impregnation chamber 114, the calibration die 116, the first polymerization die 117 and the second polymerization die 118 are arranged along the same axis corresponding to the longitudinal axis X-X' of the installation 100 in the longitudinal direction X. Generally, the fibers are delivered by one or more reels 112, called "rovings" in English terms. The bundle, coming from the feed device 111, passes through the installation, advancing in the direction of the arrow F, being set in motion by the drive device D located at the outlet of the device.

[0107] The drive device D is, for example, of the type comprising a motorized traction drum for winding the composite element around its axis or comprising two motorized drums facing each other, spaced apart by a corresponding distance at least equal to the thickness of the composite element and which rotate in opposite directions to drive the composite element EF, by friction, in a translational movement, making it pass into the space located between the two drums. Alternatively, any drive device could be used to set the bundle of multifilament fibers in motion in a direction of advance.

[0108] The vacuum chamber 113 is, in a manner known per se, delimited by a rigid inlet nozzle 113a, provided with a through orifice and a rigid separation nozzle 113b, also provided with a through orifice located axially opposite the orifice of the inlet nozzle 113a.

[0109] The bundle of multifilament fibers EO is introduced into the vacuum chamber 113 by passing it through the orifice of the inlet nozzle 113a and exits through the orifice of the separation nozzle 113b.

[0110] The vacuum chamber 1 13 is connected to a vacuum pump (not shown) which maintains a pressure level of approximately 0. lbar in the vacuum chamber 1 13, despite the passage of the bundle of multifilament fibers EO through the orifice having a diameter greater than that of the bundle of multifilament fibers EO which passes through them.

[0111] The vacuum chamber 1 13 allows the bundle of EO multifilament fibers to be degassed by the action of the vacuum and thus to reinforce the effectiveness of the subsequent impregnation and above all to guarantee the absence of bubbles inside the final composite monostrand.

[0112] After passing through the vacuum chamber 113, the bundle of multifilament fibers EO enters an impregnation chamber 114 which is completely full of polymerizable impregnation material, therefore free of air.

[0113] The impregnation chamber 114 is an airtight enclosure, delimited by the separation nozzle 113b and a rigid calibration nozzle, also provided with a through orifice located axially opposite the orifice of the separation nozzle 113b.

[0114] The impregnation chamber 114 is supplied with polymerizable material 115 coming from an external reservoir (not shown) via an inlet pipe 114a, here located in the upper part of said impregnation chamber 114.

[0115] The impregnation chamber 114 may also comprise, for example on its lower part, a discharge pipe (not shown) for the polymerizable material.

[0116] The impregnation chamber 114 is completely filled with polymerizable material so that the bundle of multifilament fibers exiting the vacuum chamber 113 and passing through it in a linear path is completely impregnated with polymerizable material.

[0117] The impregnation chamber 114 is, here, associated with a heating device 114b configured to heat the polymerizable material to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0118] Thus, the impregnated multifilament fiber bundle leaves the impregnation chamber 1 14 at a temperature between 50°C and 95°C, preferably between 60°C and 80°C before passing through the radiation dies 1 17, 1 18.

[0119] Alternatively, such a heating device 1 14b could not be provided.

[0120] The calibration die 1 16 here comprises a calibration nozzle configured to shape the bundle of multifilament fibers exiting the impregnation chamber 1 14 to form an impregnated single strand E1. The first radiation device 1 17 comprises a first light source 1 17a which combines ultraviolet radiation, acronym UV, and infrared radiation, acronym IR.

[0121] The exposure time of the El-impregnated multifilament fiber bundle to the first combined ultraviolet / infrared light source is between 0.1 s and 1.5 s, preferably between 0.4 s and 0.7 s.

[0122] The power of the first light source with combined ultraviolet / infrared radiation is between 2 kW and 14 kW, preferably between 4 kW and 7 kW.

[0123] For example, the first light source comprises a plurality of light-emitting diodes (not shown), acronym LED, preferably directed radially towards the impregnated multifilament fiber bundle E l .

[0124] For example, the power of LEDs is between 2kW and 14 kW, preferably between 4 kW and 7 kW.

[0125] According to yet another variant, the first light source with radiation is configured to emit only monochromatic ultraviolet radiation, for example via LEDs, the available wavelengths of which are as follows: 365, 385, 395, 405nm, and more generally between 200nm and 405nm.

[0126] The first 1 17a LED ultraviolet light source therefore makes it possible to emit radial radiation on the El impregnated single strand, with or without reflectors to optimize irradiation.

[0127] According to yet another variation, the first light source 117a could comprise a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet (UV) radiation, infrared radiation, and visible light.

[0128] The first radiation device 117 is configured to partially polymerize or pre-polymerize the impregnated multifilament fiber bundle E1 and deliver a pre-polymerized impregnated multifilament fiber monostrand E2. By "partial polymerization or pre-polymerization" is meant that the degree of polymerization of the multifilament fiber bundle has reached between 35% and 65% of complete polymerization.

[0129] The pre-polymerization step makes it possible to obtain a pre-polymerized, non-sticky single strand of fibers, capable of no longer deforming in the free state while being malleable to be deformed under mechanical stress.

[0130] The first radiation device 117 is delimited by an inlet plate 117b, visible in figures 3 and 4, rigid, provided with a through orifice 117c and an outlet plate 117d, rigid, also provided with a through orifice 117e located axially opposite the orifice 117c of the inlet plate 117b.

[0131] The inlet plate 117b comprises a through hole 117f for supplying oxygen inside the first radiation device 117 and the outlet plate 117d comprises a through hole 117g for supplying nitrogen or nitrogen inside the first radiation device 117 and a through hole 117h for discharging the gaseous fluids to the outside.

[0132] The single strand impregnated with polymerizable material E1 is introduced into the first radiation device 117 by passing it through the orifice 117c of the inlet plate 117b and exiting through the through orifice 117e of the outlet plate 117d.

[0133] The first radiation device 117 comprises a guide tube 120 of the impregnated single strand El which enters said first radiation device 117.

[0134] The guide tube 120 extends over the entire length of the first radiation device between an input base 132, visible in Figures 3 to 5 and a stiffening base 131 visible in Figure 5 of a fixing device 130 which will be described in detail with reference to Figure 5.

[0135] The guide tube 120 is made of a transparent or translucent material permeable to oxygen through which the single strand impregnated with polymerizable material E1 circulates. The outer surface of the single strand impregnated with polymerizable material E1 entering the first radiation device a1 17 is in contact with the inner surface of the guide tube 120.

[0136] The oxygen-permeable tube 120 makes it possible to inhibit the photopolymerization of the polymerizable material, so that said outer surface of the single strand impregnated with polymerizable material E1 still remains liquid at the outlet of the first radiation device 117.

[0137] For example, the tube is made of a thermoplastic polymer, such as polytetrafluoroethylene (PTFE) known, for example, under the registered trademark "Teflon™", preferably an amorphous fluoropolymer, with the acronym "AF".

[0138] Preferably, the tube is made of amorphous fluoropolymer having a glass transition temperature of 240°C.

[0139] The guide tube 120 comprises a wall with a thickness of between 0.1 mm and 0.8 mm.

[0140] The input base 132 is mounted in the through-hole 117c of the input plate 117b of the first radiation device 117 and comprises a first passage 132a for the impregnated single-strand E1 and a second passage 132b, coaxial with the first passage 132a, for fixing a first end 121 of the guide tube 120.

[0141] The first passage 132a has a diameter smaller than the diameter of the second passage 132b and in particular than the diameter of the guide tube 120, so as to form a seal for the first radiation device 117.

[0142] As illustrated in detail in FIG. 5, the fixing device 130 of the guide tube 120 comprises the input base 132 secured to the input plate 117b of the first radiation device 117 and the stiffening base 131.

[0143] As illustrated, the stiffening base 131 is not, here, directly fixed to the casing of the first radiation device 117. Alternatively, it could be provided that the stiffening base 131 is fixed inside the first radiation device 117, or even to the output plate 117d. The fixing device 130 of the guide tube 120 further comprises a plurality of holding fins 133 in the form of thin plates arranged parallel to one another along the axis of advancement X-X' and axially separated from one another by a constant distance.

[0144] Each retaining fin 133 comprises a central orifice 133a for the passage of the guide tube 120 and two end orifices 133b for the passage of the stiffening rod 134.

[0145] The fixing device 130 of the guide tube 120 further comprises two stiffening rods 134 each extending along a longitudinal axis parallel to the axis of advancement X-X' and parallel to each other. Alternatively, it could be provided that only one stiffening rod or more than two stiffening rods.

[0146] The stiffening rods 134 are integral with the stiffening base 131.

[0147] The holding support 130 is, for example, made of plastic material, such as for example polycarbonate (PC), semi-crystalline thermoplastic (PPS), or polyetheretherketon (PEEK).

[0148] The second radiation device 1 18 or final radiation device comprises a second light source 1 18a with combined ultraviolet and infrared radiation or infrared radiation alone configured to complete the polymerization of the pre-polymerized impregnated multifilament fiber bundle, called pre-polymerized monostrand E2.

[0149] Complete polymerization of the composite is obtained when the degree of polymerization of the polymerizable material is close to 100%, preferably greater than or equal to 95%.

[0150] The exposure time of the pre-polymerized monostrand E2 to the second light source combining ultraviolet and infrared rays is between 1 s and 6 s, preferably between 1.5 s and 3 s.

[0151] The power of the second light source with combined UV and infrared radiation is between 10 kW and 60 kW, preferably between 20 kW and 40 kW. According to a variant, the second light source comprises a plurality of light-emitting diodes (not shown), acronym LED, preferably directed radially towards the pre-polymerized single strand E2, the available wavelengths of which are between 200 nm and 405 nm, preferably between 365 nm and 405 nm.

[0152] According to another variant, the second light source 1 18a could comprise a plurality of mercury vapor lamps, the exposure time of the pre-polymerized single strand E2 of which is between 1 s and 4 s, preferably between 1.5 s and 2 s, at a power of between 10 kW and 60 kW, preferably between 20 kW and 40 kW.

[0153] Alternatively, the second light source 118a could comprise a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation (UV), infrared radiation and visible light and a plurality of lamps with an infrared radiation wavelength between 1 pm and 3 pm.

[0154] According to yet another variant, the second light source could be solely infrared radiation. The second radiation device in this case comprises a solely infrared radiation light source configured to emit only infrared radiation, with a wavelength between 1 pm and 3 pm.

[0155] In this case, the duration of exposure of the pre-polymerized single strand E2 to the second light source combining infrared radiation alone is between 2s and 8s, preferably between 3s and 4s and the power of this second infrared light source is between 100kW and 60kW, preferably between 20kW and 40kW.

[0156] Alternatively, a third radiation device could be provided downstream of the second radiation device.

[0157] The installation according to the invention makes it possible to continuously produce a single strand of composite shaped by the guide tube and requiring no post-treatment.

[0158] Such an installation can easily be implemented on all existing composite reinforcement production lines. Thanks to the guide tube, it is possible to give a circular shape to the section of the single strand before final polymerization.

Claims

CLAIMS 1. Installation (100) for the continuous manufacture of an elongated composite element (EF) comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material, the installation (100) comprising, in the direction of advance (X-X') of the bundle of multifilament fibers: - a feed device (111) configured to form a bundle of multifilament fibers (E0); a degassing chamber (113) for the bundle of multifilament fibers (E0); - an impregnation chamber (114) filled with a composition based on a polymerizable material and configured to impregnate said degassed bundle of multifilament fibers (E0) with said composition and form an impregnated single strand (E1), said impregnation chamber (114) being located downstream of the degassing chamber in the direction of advancement of the bundle of multifilament fibers; and - a first radiation device (117) through which the impregnated single strand (E1) of polymerizable material circulates and configured to carry out a partial polymerization of said impregnated single strand (E1) to form a pre-polymerized single strand (E2); and at least - a second radiation device (118), separate and distinct from the first radiation device (117) configured to form a final composite monostrand (EF), and - a translational drive device (D) configured to drive the bundle of multifilament fibers in translation and to apply tension to said bundle of multifilament fibers, characterized in that the first radiation device (117) comprises a guide tube (120) made of translucent material permeable to oxygen through which the impregnated single strand (E1) circulates.

2. Installation (100) according to claim 1, in which the guide tube (120) is made of thermoplastic polymer.

3. Installation (100) according to claim 1 or 2, in which the guide tube (120) comprises a wall with a thickness of between 0.1 mm and 0.8 mm.

4. Installation (100) according to any one of the preceding claims, in which the first radiation device (117) comprises a fixing device (130) for the guide tube (120), and in which the guide tube (120) extends over the entire length of the first radiation device (117) between an input base (132) and a stiffening base (131) of the fixing device (130).

5. Installation (100) according to any one of the preceding claims, in which the fixing device (130) further comprises a plurality of holding fins (133) arranged in parallel to one another along the axis of advancement (X-X') and axially separated from one another, each holding fin (133) comprising a central orifice (133a) for the passage of the guide tube (120).

6. Installation (100) according to claims 4 and 5, in which the fixing device (130) further comprises at least one stiffening rod (134) secured to the stiffening base (131) and in which each holding fin (133) comprises an end orifice (133b) for the passage of the stiffening rod (134).

7. Installation (100) according to claim 6, in which the fixing device (130) comprises two stiffening rods (134) each extending along a longitudinal axis parallel to the axis of advancement (X-X') and parallel to each other and in which each holding fin (133) comprises two end orifices (133b) for the passage of a stiffening rod (134).

8. Installation (100) according to claim 4 in combination with any one of the preceding claims, in which the first radiation device (117) is delimited by a rigid inlet plate (117b), provided with a through orifice (117c) and a rigid outlet plate (117d), also provided with a through orifice (117e) located axially opposite the orifice (117c) of the plate input (117b), and in which the input base (132) of the fixing device (130) is integral with said input plate (117b).

9. Installation (100) according to claim 8, in which the inlet base (132) is mounted in the through-hole (117c) of the inlet plate (117b) of the first radiation device (117) and comprises a first passage (132a) for the impregnated multifilament fiber bundle (El) and a second passage (132b), coaxial with the first passage (132a), for fixing the guide tube (120).

10. Installation (100) according to any one of the preceding claims, in which the first radiation device (117) comprises a first light source (117a) with combined ultraviolet and infrared radiation.

11. Installation (100) according to any one of the preceding claims, in which the first light source (117a) comprises a plurality of light-emitting diodes configured to emit monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm.

12. Installation (100) according to claim 10, in which the first light source (117a) with ultraviolet radiation comprises a plurality of mercury vapor lamps configured to emit broad spectrum ultraviolet radiation UV, infrared radiation and visible light.

13. Installation (100) according to any one of the preceding claims, in which the second radiation device (118) comprises a second light source (118a) with combined ultraviolet and infrared radiation or infrared radiation alone to complete the polymerization of the pre-polymerized single strand (E2).

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