FR3067438B1 - FLEXIBLE LINE CONNECTION TIP, FLEXIBLE LINE AND METHOD THEREOF - Google Patents

Abstract

The tip (14) defines at least one exhaust passage (60) of a gas. It comprises a selective sealing element (62) disposed in the exhaust passage (60), adapted to allow the evacuation of gas through the discharge passage (60) in the direction from the interior to the outside the flexible line and to prevent fluid flow through the exhaust passage (60) beyond the selective sealing member (62) from the outside to the inside. At least one bidirectional closure member (66) of the exhaust passage (60) is disposed in the exhaust passage (60) and / or at its outlet. The bi-directional closure member (66) is adapted to transition from a closed closure configuration of the exhaust passage (60) to an open discharge configuration of a gas overpressure in the exhaust passage (60). ).

Description

Connection end of a flexible line, flexible line and associated method

The present invention relates to a connecting end of a flexible line, the flexible line having at least one tubular sheath and at least one longilinkedisposé around the tubular sheath, the tip comprising: - an end portion of the tubular sheath; an end section of each elongate element; an end vault and a cover delimiting a reception chamber of each end section; the nozzle defining at least one exhaust passage of a gas present in the flexible line out of the flexible line, the nozzle comprising a selective shutter element disposed in the exhaust passage, the element of selective closures being adapted to allow gas to escape through the discharge passage in the direction from the inside to the outside of the flexible line and to prevent fluid circulation through the exhaust passage beyond the element of selective fillings from outside to inside.

The flexible line is in particular a flexible pipe as described for example in the normative documents API 17J (Specification for Unbounded Flexible Pipe), API RP17B (Recommended Practice for Flexible Pipe) and API 16C (Choke and Kill Equipment) prepared by American Petroleum Institute. The flexible pipe is advantageously of the unbonded type.

The pipe is generally formed of a set of concentric layers and superposed. It is considered as "unbound" in the sense of the present invention when at least one of the layers of the pipe is able to move longitudinally relative to the adjacent layers during bending of the pipe. bound is a conduct devoid of bonding materials

In a variant, the flexible pipe is an integratedproduction bundle, comprising at least one fluid transport tube and a set of electric or optical cables capable of transporting electrical or hydraulic power or information between the bottom and the surface of the pipe. the expanse of water.

More generally, the flexible line is an umbilical, as described in the normative document published by the American Petroleum Institute (API), API17E "Specificationfor Subsea Umbilicals".

The flexible pipes generally comprise an outer protective sheath defining an interior volume and at least one impervious sheath disposed within the interior volume.

This impermeable sheath is for example a pressure sheath delimiting a fluid circulation passage or an intermediate sheath disposed between the vacuum sheath and the outer sheath.

Traction armor layers formed by generallymetal wire plies are disposed in the annular space between the impermeable sheath and the outer lagoon to provide good tensile strength.

Gases that are contained in the fluids transported by the pipe, such as hydrocarbons, carbon dioxide, and hydrogen sulphide are likely to pass into the annular space by diffusion through the sheath (s).

These gases, and the water which may possibly diffuse into the ring, are liable to corrode the armor elements. In addition, these gases accumulate in the annulus when the pipe is located at the bottom of the body of water. When the pipe is raised to the surface, it is necessary to evacuate the gases, otherwise the outer sheath is likely to burst, since the hydrostatic pressure applied on the pipe significantly decreases.

To avoid this phenomenon, it is known, for example, to connect the annular space to the outside of the pipe by a gas evacuation passageway extending through the nozzle.

The passage is provided with a clean valve to open in case of overpressure inside the pipe with respect to the external pressure.

Such a device is effective, but can still be improved. Indeed, although the valve described in EP0341144 is tested at the factory by subjecting it to external pressure, it may encounter a mechanical malfunction. Sometimes organisms and / or sand may clog the valve and prevent it from closing again.

In this case, the water located outside the pipe is likely to enter the annular space through the valve itself, and / or through the sealing means disposed around the valve.

This is not satisfactory, especially in applications where the pipeline supplier must ensure that the annular space of the pipe will never be flooded during the period of use.

An object of the invention is therefore to provide a tip for a flexible line that prevents the bursting of the outer sheath during a recovery of the pipe, all gambolling that the flexible line will not be flooded during normal use. To this end, the invention relates to a tip of the aforementioned type, characterized by: - at least one bidirectional closure member of the evacuation passage located in the evacuation passage and / or at its exit, the closing memberbidirectional being able to pass from a closed shutter configuration of the evacuation pass to an open configuration of evacuation of a gas overpressure in the exhaust passage. The tip according to the invention may comprise one or more of the following characteristics, taken in isolation or in any technically possible combination: at least one bidirectional closure member is formed by a rupture disc capable of passing from its closed configuration its open configuration split; the rupture disc is formed of a polymeric material or a metallic material; the rupture disc has at least one hollow part defining at least one preferential rupture zone, of thickness less than the thickness of a peripheral zone of the rupture disc, the hollow part having a circular or cross-shaped contour; - The tip has a transverse bearing surface of the bi-directional closure member disposed transversely relative to the discharge passage, the transverse bearing surface defining a through opening, the tip comprising a veneer organ of the organ bidirectional closure on the support surface transverse, the bidirectional closure member being held stationary between the transverse support surface and the veneer member, facing the through opening; the endpiece comprises an additional support interposed between the transverse support surface and the bidirectional closure member opposite the through opening, the additional support being mounted free with respect to the transverse support surface; at least one bidirectional closure member is situated downstream of the selective sealing element, in the direction going from the inside towards the outside of the flexible line; at least one bidirectional closure member is located in the selective sealing element; the selective sealing element comprises a movable valve, and a piercing member of the bidirectional closure member, mounted movably together with the mobile valve; at least one bidirectional closure member is located upstream of the selective sealing element, in the direction going from the inside towards the outside of the flexible line; the bidirectional closure member is mounted coaxially with the selective sealing element; at least one bidirectional closure member is formed by a device that can be serviced from outside the flexible line; the nozzle defines at least one auxiliary passage for discharging a gas present in the flexible line towards the outside of the flexible line, distinct from the evacuation passage, the auxiliary evacuation passage being devoid of any element of selective shutter disposed in the auxiliary discharge passage, the nozzle comprising an auxiliary bi-directional closure member of the auxiliary discharge passage disposed in the evacuation and / or outlet passageagail, the bidirectional auxiliary closure member being able to pass through a closed shutoff configuration of the auxiliary evacuation passage to an open discharge configuration of a gas overpressure in the auxiliary evacuationpassage. The invention also relates to a flexible line, comprising: - at least one tubular sheath - at least one elongate element disposed around the tubular sheath, - a tip as defined above. The invention further relates to a method comprising the following steps: - accumulation of gas in a flexible line as defined above, the bidirectional closure member occupying its closed configuration; passing the bidirectional closure member from its closed configuration to its open configuration; - Evacuation of the gas out of the flexible line by circulation through the evacuation pass, the selective shutter element and the bidirectional closure member.

The method according to the invention may comprise one or more of the following characteristics, taken separately or in any combination technically possible: the bidirectional closure member comprises a rupture member, the bidirectional closing member passing from its closed configuration in its open configuration by bursting of the rupture member under the effect of an overpressure; - The bidirectional closure member comprises a valve, the bi-directional closure member passing from its closed configuration to its open configuration paractionnement the valve from outside the pipe; - gas accumulation occurs when the flexible line is placed deep into the body of water, the discharge passage of the bi-directional closure member from its closed configuration to its open configuration occurring before a rise of the line flexible towards the surface, or during the ascent of the flexible line to the surface. The invention will be better understood on reading the description which will follow, given solely by way of example, and with reference to the appended drawings, in which: FIG. 1 is an exploded perspective view of the central section of FIG. a flexible line according to the invention; FIG. 2 is a partial view, taken along a median axial plane, of a detail of a tip of the flexible line according to the invention, provided with a bi-directional closing element arranged downstream of a selective sealing element; ; FIG. 3 is a view from above of the detail of FIG. 2; FIG. 4 is a detailed view of the bidirectional closure member; - Figure 5 is a view similar to Figure 2 during the opening of the bidirectional closure member; FIG. 6 is a view similar to FIG. 5 for another nozzle according to the invention; - Figures 7 and 8 are views similar respectively to Figures 3 and 4 for another nozzle according to the invention; FIGS. 9 and 10 are views similar respectively to FIGS. 3 and 4 for another nozzle according to the invention; - Figures 11, 12 and 13 are views similar to Figures 2, 4 and 5 respectively for another nozzle according to the invention, wherein the bi-directional closure member is disposed upstream of the selective sealing member; FIGS. 14 and 15 are cross-sectional views of a closure member selectively provided with a bidirectional closure member, respectively in its closed configuration and in its open configuration; FIG. 16 is a view similar to FIG. 14, for an alternative variant of selective shutter; - Figure 17 is a sectional view along a median axial plane of another nozzleaccording to the invention.

In all that follows, the terms "upstream" and "downstream" refer to the normal flow of a fluid. In particular, they are generally understood here from within the flexible line to the outside of the flexible line.

A first flexible line according to the invention, formed by a flexible pipe 10, is partially illustrated by FIGS. 1 to 5.

The flexible pipe 10 comprises a central section 12 illustrated in part in FIG. 1. It comprises, at each of the axial ends of the central section 12, an end cap 14, partially visible in FIG.

With reference to FIG. 1, the pipe 10 delimits, in its internal volume 15, a central passage 16 for the circulation of a fluid, advantageously a petroleum fluid. The centralpass 16 extends along an axis A-A ', which it contains, between the upstream end and the downstream end of the pipe 10. It opens through the endpieces 14.

The diameter of the central passage 16 is advantageously between 50 mm (2 ") and 500 mm (20").

The fluid conveyed by line 10 is for example a gas or a liquid extracted from the marine subsoil.

The flexible pipe 10 is intended to be disposed through a body of water (not shown) in a fluid operating system, including hydrocarbons. The body of water is, for example, a sea, a lake or an ocean. The depth of the water extent to the right of the fluid operating installation is for example between 50 m and 4000 m. The fluid operating system comprises a generally floating surface assembly and a bottom assembly (not shown) which are generally interconnected by the flexible conduit 10.

In this example, the flexible pipe 10 is an "unbonded" pipe (referred to as "unbonded").

At least two adjacent layers of the flexible pipe 10 are free to move longitudinally relative to each other during bending of the pipe.

Advantageously, all adjacent layers of the flexible pipe are free to move relative to each other. Such behavior is, for example, described in the normative documents published by the American Petroleum Institute (API), API 17J (May 2014, 4th edition), API RP17B (May 2014, 5th edition) and API 16C (March 2015, 2nd edition).

As illustrated in FIG. 1, the pipe 10 delimits a plurality of concentric layers around the axis A-A ', which extend continuously along the central section 12 to the ends 14 (not visible in FIG. ends of the conduct.

The pipe 10 here comprises at least a first tubular sheath 20 based on polymeric material constituting a pressure sheath. The pipe 10 comprises a second outer tubular sheath 22 for protecting the pipe 10.

The inner sheath 20 defines with the outer sheath 22 at least one annular space.

In this example, the pipe 10 comprises, in the annular space 26, a pressure vault 30, and optionally an inner band 32 wound around the depression vault 30.

The duct 10 further comprises a plurality of tensile armor layers 34, 36 arranged externally with respect to the pressure vault 30 and with respect to the ferret 32.

Advantageously, the pipe 10 further comprises an internal carcass 42 located inside the inner sheath 20.

The carcass 42, when present, is formed for example of a profiled metal strip, wound in a spiral. The turns of the strip are advantageously stapled to each other, which takes up the radial forces of crushing. The helical winding of the profiled metal strip forming the carcass 42 is not short, that is to say it has a helix angle of absolute value close to 90 °, typically between 75 ° and 90 °.

In this example, the carcass 42 is disposed inside the inner sheath 20. The pipe 10 is then designated by the English term "rough bore" because of the geometry of the carcass 42.

Alternatively (not shown), the pipe 10 is devoid of internal carcass42, it is then designated by the term "smooth bore".

In known manner, the inner sheath 20 is intended to contain sealing fluid transported in the passage 16. It is formed of a polymer material, for example based on a polyolefin such as polyethylene or polypropylene, based on a polyamide such as PA11 or PA12, or based on a fluorinated polymer such as polyvinylidene fluoride (PVDF) or perfluoro alkoxy (PFA). The thickness of the inner sheath 20 is for example between 5 mm and 20 mm.

In this example, the pressure vault 30 is intended to take up the forces related to the pressure prevailing inside the inner sheath 20. It is for example formed of a metallic profiled wire surrounded by a helix around the sheath 20. The wire This profile preferably has a geometry, in particular a Z-shaped geometry. The Z geometry makes it possible to improve the general mechanical strength of the pipe 10 and also makes it possible to reduce its mass.

In a variant, the profiled wire has a geometry in the form of T, U, K, X or I.

The pressure vault 30 is helically wound in a short pitch around the inner sheath 20, that is to say with a helix angle of absolute value close to 90 °, typically between 75 ° and 90 °.

The band 32, when present, is constituted by a spiral winding of at least one wire advantageously of rectangular cross-section around pressure washer 30.

The superposition of several wires wound around the pressure vault 30 may advantageously replace a total thickness of the given band 32. This increases the resistance to the bursting of the pipe 10. The winding of the at least one wire is short-circuit, that is to say with a helix angle of absolute value close to 90 °, typically comprised between 75 ° and 90 °.

In an alternative embodiment of the invention, the pressure vault 30 and the band 32 are replaced by a thicker pressure vault formed from a profiled metal wire having a T-shaped geometry, of U, of K, X or I, and / or from at least one aramid band with high mechanical strength (Technora® or Kevlar®), and / or from at least one composite strip comprising a thermoplastic matrix in which carbon fibers or glass fibers are embedded.

In another embodiment of the invention, the pipe 10 does not comprise a pressure vault. Such a flexible pipe structure is said to be "balanced" (not shown).

The pipe 10 comprises at least one pair of tensile strength cross armor layers 34, 36 disposed above the band 32.

In the example shown in FIG. 1, the flexible pipe 10 comprises at least one pair of armor layers 34, 36.

As a variant, the flexible pipe 10 comprises several pairs of armor layers 34, 36 superimposed on each other, for example two pairs of inner armor layers 34, 36.

Each pair has a first layer of armor 34 applied to the fret32, to the vault 30, to the sheath 20 or to another pair of armor layers, and a second layer of armor 36, disposed around the first layer of armor armor 34.

Each armor layer 34, 36 comprises at least one longitudinal armor element wound at a long pitch about the axis A-A 'of the pipe 10.

By "wrapped with a long pitch" is meant that the absolute value of the helix angle is less than 60 °, and is typically between 20 ° and 60 °.

In the example shown in FIG. 1, the absolute value of the helix angle of each inner armor layer 34, 36 is greater than 45 °, and is in particular between 50 ° and 60 °, and is approximately equal to 5 °.

The weave members 44 of a first layer 34 are generally wound up at an opposite angle to the weave members 44 of a second layer 36. Thus, if the winding angle of the armor elements 44 of the first layer 34 is equal to + α, a being between 20 ° and 60 °, the winding angle of the armor elements 44 of the second layer 36 disposed in contact with the first layer 34 is for example - a, with a between 20 ° and 60 °.

The armor elements 44 are for example formed by metal son or composite material, or by high strength tapes.

In this example, each layer of armor 34, 36 rests on at least one anti-wear strip (not shown). The anti-wear strip is for example made of plastic, especially based on a polyamide or a polyvinylidene fluoride (PVDF). It has a thickness less than the thickness of each sheath 20, 22.

Advantageously, a holding tape such as a high mechanical resistance aramid strip (Technora® or Kevlar®) is wound around the second outermost layer of armor 36 with respect to the axis A-A ', to mechanically maintain the armor layers 34, 36. Alternatively, the aramid fibers are replaced by glass fibers.

The outer sheath 22 is intended to protect the annular space 26 by preventing the uncontrolled penetration of fluid from outside the flexible conduit 10 into the interior. It is advantageously made of a polymer material, especially based on a polyolefin such as polyethylene or polypropylene, based on a polyamide such as PA11 or PA12, or based on a fluorinated polymer such as polyfluoride divinylidene (PVDF ) or perfluoroalkoxy (PFA). The thickness of the outer sheath 22 is for example between 5 mm and 20 mm.

The outer sheath 22 is sealed. It prevents the penetration of liquid from the outside of the pipe 10 to the annular space 26. In a known manner, with reference to FIG. 2, the pipe 10 is connected to the entire surface by the nozzle 14.

Each endpiece 14 has an end vault 50, and a cover 51 defining with the vault 50 a chamber 52 for receiving the end sections of the armor elements 44, and end portions of the layers forming the pipe 10, in particular the end portions of the sheaths 20, 22, the vault 30 and the hoop 32 when they are present. The end piece 14 has crimping elements (not shown) at the end of each sheath 20, 22. The crimping elements are respectively intended to ensure the seal between the outside of the pipe 10 and the spacing element 26, and between the annular space 26 and the central passage 16, around the inner sheath 20.

In this example, the end vault 50 is intended to connect the pipe 10 to another endpiece 14 or bottom and / or surface end devices, advantageously via an end flange.

The end vault 50 has a central bore for receiving the end of the pressure sheath 20 and allowing the flow of the fluid flowing through the central passage 16 towards the outside of the pipe 10. The nozzle 14 defines in addition to an evacuation passage 60 of the gases collected in the annular space 26 to convey them outside the flexible pipe 10. The tip14 further comprises a selective closing element 62 of the passage 60, disposed in the passage of 60 and advantageously, a sealing assembly 64 mounted in the end of the selective sealing element 62.

According to the invention, the tip 14 further comprises a bi-directional closure member 66 interposed in the evacuation passage 60, and an assembly 68 disassembly of the bidirectional closure member 66.

The evacuation passage 60 connects the annular space 26 to an outlet orifice 70 opening radially outwardly of the nozzle 14. It extends successively through the chamber 52, and through the arch 50.

According to an alternative embodiment of the nozzle (not shown), the outlet port 70 opens out of the nozzle 14 in a direction that is not radial to the axisA-A '. For example, the outlet orifice opens out of the nozzle in a longitudinal direction or substantially oblique with respect to the axis A-A '.

In the example shown in Figure 2, the exhaust passage 60 is delimited upstream by a conduit 72 through the chamber 52 to the roof 50. It comprises enaval a longitudinal section 74 and a section 76 radial formed in the vault 50.

The longitudinal section 74 here advantageously extends in an inclined manner with respect to the axis A-A 'of the central passage 16.

The radial section 76 comprises, radially away from the axis A-A ', a regionamont 78, an intermediate region 80 of transverse extent greater than that of the upstream region 78, and a downstream region 82 of transverse extent greater than that of intermediate region 80.

The intermediate region 80 and the upstream region 78 delimit between them an inner shoulder 84 on which rests the sealing assembly 64. It has on its peripheral surface an internal thread.

The downstream region 82 and the intermediate region 80 define between them an external shoulder 86 at the selective closure element 62.

The downstream region 82 has an outer edge 88 on which rests the disassembly assembly 68 of the bidirectional closure member 66. The selective sealing element 62 is able to permanently prevent the passage of fluid through the orifice 70 in the direction from the outside to the inside of the pipe 10.

It is furthermore capable of allowing the evacuation of gas through the evacuation passage 60 in the direction from the inside of the pipe 10 towards the outside, when the pressure difference between the upstream of the closure element selective 62 and the downstream of the selective shutter element 62 is greater than a given threshold value. The selective sealing member 62 is adapted to prevent the passage of fluid, when the pressure difference between the upstream of the selective sealing member 62 and the downstream of the selective sealing member 62 is less than the given threshold value.

In this example, the selective sealing member 62 is formed by a non-return valve.

Referring to Figure 14, it comprises a hollow base body 90, mounted in the passage 60, preferably between the intermediate region 80 and the downstream region 82, and uninsert 92 partially closing the hollow base body 90, defining with the base body 90, a through passage 95 of fluid circulation. The selective sealing member 62 further comprises a shutoff valve 94 movably mounted in the circulation passage 95 between a closed position 95, shown in FIG. 14, and an open position of the passage 95. It comprises a calibrated spring 96 able to permanently urge the valve 94 towards the closing position. The selective closure member 62 defines a seat 98 protruding in the passage 95 for sealing the valve 94 in the closed position.

The seat 98 prevents the displacement of the valve 94 towards the interior of the duct 10.

In this example, the valve 94 is hollow. It has an inner cavity 100 and through openings 102 for gas passage opening into the inner cavity 100.

In the closed position, the valve 94 rests on an inner surface of the seat 98 and seals the passageway 95. The valve 94 is held against the seat 98 by the spring 96 as long as the pressure difference between the upstream end selective shutter element 62 and the downstream of the selective shutter element 62 is below the given threshold value.

When the pressure difference between the upstream of the selective sealing member 62 and the downstream of the selective sealing member 62 increases above the threshold value, the valve 94 moves outwardly toward the outside. against the force generated by the spring96.

The valve deviates from the seat 98, allowing the passage of gas from the interior to the outside, especially from the annular space 26 through the evacuation pass 60.

The threshold value depends on the stiffness of the spring 96. This threshold value is for example greater than 1 barg and is in particular between 0.5 barg and 5 barg. The sealing assembly 64 is here formed by a ring 104 disposed in abutment with the internal shoulder 84 and the selective sealing element 62.

Figure 14, which illustrates a variation, has been used herein to describe the main elements of the selective sealing member 62. In contrast to Figure 14, in the embodiment of Figures 1 to 5, the two-dimensional closure member 66 it is advantageously not worn by the selective sealing element 62.

In the example shown in FIGS. 1 to 5, the two-dimensional closure member 66 is disposed downstream of the selective sealing element 62. The two-dimensional closure member 66 is intended to prevent the water from reaching the range of water to penetrate inside the annular space 26, while allowing gases to be evacuated from the annular space 26 towards the outside when opening the selective sealing element 62, for example during The bi-directional closing member 66 is here formed by a rupture disc 110 mounted transversely in the passage 60 or at the outlet thereof.

The rupture disc 110 is advantageously formed of a polymer material, especially based on a polyolefin such as polyethylene or polypropylene, based on a polyamide such as PA11 or PA12, based on a fluoropolymer such as polyfluoride. vinylidene (PVDF) or perfluoroalkoxy (PFA), or based on a polyurethane.

The disk 110 may also be formed from a metallic material such as, for example, a carbon steel, a stainless steel, aluminum, titanium, platinum or again, from a metal alloy such as an alloy of nickel (Hastelloy or Monel) or super-nickel alloy (Inconel). The mounting assembly 68 includes a plate 112 mounted on the outer edge 88 for receiving the rupture disc 110, and a member 114 for plating the rupture disc 110. The mounting assembly 68 advantageously comprises a closing plate 116.

The plate 112 comprises a peripheral sleeve 120 defining a central hole 122 and a perforated transverse wall 124 interposed in the central hole to receive in support the rupture disc 110.

The peripheral sleeve 120 is fixed on the roof 50 for example by screwing. A seal 126 is interposed between the sleeve 120 and the outer edge 88.

The central hole 122 here defines the outlet of the passage 60.

The perforated transverse wall 124 defines a transverse surface 128 for supporting the rupture disc 110. It has at least one through opening 130 opening into the transverse surface 128.

The locking ring 114 is inserted into the peripheral sleeve 120 to seat the periphery of the rupture disk 110 against the transverse bearing surface 128. The ring 114 is fixedly held by means of the closure plate 116 disposed externally and exerting a pressure contact on it.

Alternatively, the locking ring 114 is fixed in the peripheral sleeve 120, for example by screwing.

It has a central lumen 132, which opens opposite the rupture disc 110.

With reference to FIG. 4, the ratio between the transverse extent D1 of the reversing opening 130 and the thickness E of the rupture disc 110 is defined as a function of the maximum external pressure that the rupture disc 110 must withstand in service. The higher the pressure, the smaller the transverse extent D1 and the greater the thickness E. Generally, the thickness of the disk 110 is between 1 mm and 10 mm, in particular between 3 mm and 5 mm. The maximum transverse extent D1 of the reversing opening 130 is for example between 0.5 mm and 5 mm, in particular between 1 mm and 3 mm. The maximum transverse extent D2 of the central lumen 132 and the thickness E of the disk 110 are furthermore chosen as a function of the maximum permissible differential pressure between the inside and the outside of the pipe 10. The higher the differential pressure, the higher the transverse extent D2 is reduced, and the thickness E is increased. Generally, the maximum transverse extent D2 of the central lumen 132 is between 10 mm and 30 mm, in particular between 15 mm and 25 mm.

The maximum permissible differential pressure is less than the bursting pressure of the outer sheath 22.

When a differential pressure below the maximum pressure differential is applied, the bidirectional closure member 66 occupies a sealed configuration of sealing the exhaust passage 60. It prevents the gas present within the exhaust passage 60 upstream of the bi-directional closure member 66 to exit the line 10, even if the selective sealing member 62 allows it to pass. It also prevents the liquid present outside the pipe 10 from entering the exhaust passage 60 beyond the bidirectional closure member 66.

When a differential pressure greater than the maximum pressure differential is applied, the bi-directional closing member 66 spontaneously passes into an open configuration for discharging a gas overpressure into the exhaust passage 60.

In the case where the bi-directional closure member 66 is a rupture disc 110, it is capable of breaking in the region facing the through opening 130 and the central lumen 132 to allow the gas to pass as illustrated in FIG. figure 5.

Preferably, the maximum permissible differential pressure of the bi-directional closure member 66 is less than the threshold value at which the selective quenching element 62 passes the gases. Thus, as soon as the selective sealing element 62 opens to allow the gases to pass from the annular space 26, the bidirectional closure member 66 spontaneously passes into its open evacuation configuration.

In particular, the burst differential pressure of the rupture disc 110 is lower than the given threshold value of displacement of the valve 94 towards the outside.

The closure plate 116 is fixed to the sleeve 120 to cover the central lumen 132 and to compress the locking ring 114 on the rupture disc 110. It defines the orifice 70 through which the gas escapes out of the pipe 10 .

The operation of the nozzle 14 according to the invention will now be described.

Initially, after the manufacture of the pipe and the assembly of the nozzle 14, the selective sealing member 62 is put in place in the passage 60. Its malfunction is tested at the factory.

This being done, the rupture disk 110 is put in place on the transverse bearing surface 128. The dimensions of the rupture disk 110 have been chosen according to the maximum differential pressure tolerated between the annular space 26 and the outside of the pipe. 10, and the maximum external pressure that must bear the rupture cap 110, as explained above.

Then, the locking ring 114 is inserted into the central hole 122 to enclose a peripheral region of the rupture disc 110 between the locking ring 114 and the transverse bearing surface 128.

The plate 112 and the closure plate 116 are mounted on the roof 50, at the level of the outer edge 88. The assembly can be carried out on the ground, or else directly on the laying ship. The bi-directional closure member 66 formed by the rupture disk 110 closes completely the exhaust passage 60 preventing water penetration beyond the closure member 66.

This is the case even if a malfunction occurs on the selective sealing element 62, or on the sealing assembly 64, especially from the beginning of the use of the pipe 10.

Such a sealing ensures that the annular space 26 is not flooded by water during the immersion of the pipe 10. This allows, therefore, in cases where the differential pressure (difference between the pressure in the annular space 26 and the pressure external to the pipe 10) is kept below the maximum allowed differential pressure and there is no condensation of water in the annular space 26after diffusion of water through the pressure sheath 20, in s' for example, by freeing common corrosion phenomena, optimizing the selection of undercut materials 30, 32, 34 and 36 in particular and thereby reducing the thickness of the mechanical elements of the pipe. This concerns in particular the wires constituting the depression vault 30, the inner band 32 and the tensile armor layers 34, 36.

The laying of the pipe is simplified and the size of the necessary equipment (for example the buoys) for the pipe to adopt an adequate configuration in the body of water is reduced.

In addition, the pipe 10 has a better lateral buckling resistance of the armor elements 44, and does not require cathodic protection of the armor elements44.

The simple mounting of the rupture disk 110 makes it possible to modify the conditions of use of the pipe, with minimal impact on the pipe 10 itself. Cemetering can be done directly on a laying ship.

The pipe 10 can thus be immersed simply, and safely in the water extent.

When raising the pipe 10, if the differential pressure starting from the bidirectional closing member 66 increases beyond the maximum permissible differential pressure, the bidirectional closure member passes into its open configuration, advantageously by bursting the disc 110, to release the pressurized gas present inside the pipe 10, as illustrated in FIG. 5.

This prevents bursting of the outer sheath 22.

In the variant illustrated in FIG. 6, the perforated transverse wall 124 delimits, in the transverse bearing surface 128, a bowl 150 extending around the through opening 130. The tip 14 further comprises an additional support 152, mounted freely relative to the rupture disc 110 and relative to the perforated transverse wall 124, while being received in the bowl 150.

The additional support 152 covers the through opening 130 and is applied against the rupture disc 110. It is made of metal.

The additional support 152 prevents creep of the rupture disc 110 through the through opening 130 under the effect of the external pressure. However, it completely resumes the internal pressure applying through the through opening 130, and transmits it freely to the rupture disc 110.

The operation of the tip 14 illustrated in these figures remains similar to that previously written.

In the variant illustrated in FIGS. 7 and 8, the rupture disk 110 has at least one hollow portion 160 defining a preferential zone of rupture, of thickness less than the thickness of a peripheral zone of the rupture disk 110.

The preferred zone of rupture formed by the hollow portion 160 here has a circular contour.

Furthermore, the perforated transverse wall 124 comprises a plurality of decentralized opening openings 130, distributed around the central axis of the rupture disc 110.

In the variant illustrated in Figures 9 and 10, the hollow portion 160 has a cross shape. The through openings 130 eccentric are arranged between the branches of the cross.

Alternatively (not shown), the disk 110 has a plurality of hollow portions 160 defining a grid. The tip 14 illustrated in FIGS. 11 and 12 differs from that shown in FIGS. 2 to 5 in that the bidirectional closure member 66 is disposed upstream of the selective sealing element 62.

In this example, the bidirectional closure member 66 is placed in the upstream region 78 of the segment 76, on an upstream shoulder 164.

With reference to FIG. 12, the upstream shoulder 164 defines the bearing surface 128 which has a through opening 130 at its center.

The locking ring 114 is screwed into the upstream region 78 to press the periphery of the rupture disk 110 against the bearing surface 128. The selective sealing element 62 is mounted downstream of the locking ring 114.

The operation of the tip 14 is also similar to that described previously.

When a differential pressure applying on either side of the bi-directional closing member 66 increases beyond the maximum differential pressure, the bidirectional closure member 66 passes into its open configuration, advantageously by bursting the disk 110. , to release the pressurized gases inside the pipe 10, as illustrated in FIG. 13.

The disk 110 bursts in the central lumen 132 defined in the ring 114.

The rupture disk 110 being disposed upstream of the selective sealing element 62, it is not subject except exceptions to the water of the body of water and therefore remains reliable over time.

In the variant shown in FIGS. 14 and 15, the two-way closure member 66 is disposed directly in the selective sealing element 62, here below the valve 94.

In this example, the bidirectional closure member 66 is disposed in a bowl 170 formed in the upper part of the insert 92.

A perforated transverse wall 124 is disposed in the bowl 170, under the rupture tab 110 to define a bearing surface 122 which supports the rupture disc 110.

When a differential pressure applying on either side of the bi-directional closure member 66 increases beyond the maximum differential pressure, the bi-directional closure member 66 passes into its open configuration, preferably by torsion and / or bursting of the disk 110 to release the pressurized gases inside the pipe 10, as illustrated in FIG.

The presence of the bidirectional closure member 66 mounted at the downstream end of the selective sealing member 62 ensures that the valve 94 and the spring 96 remain safe from contamination by both water and water. solid materials or organisms likely to enter the tip 14.

In the variant illustrated in FIG. 16, the selective sealing element 62 furthermore comprises a piercing member 172 movably mounted on the valve 94 to move together with the valve 94 between the closed position of the passage 95 and the open position of passage 95.

In the opening position of the passage 95, the piercing member 172 pierces the transverse wall 124 and the rupture disk 110 to release the pressurized gases present inside the pipe.

In the variant illustrated in FIG. 17, the bidirectional closure member 66 is formed by an actuatable valve 180 from outside the pipe 10. The valve 180 is for example disposed in a duct 182 projecting along the vault 50. The tip 14 further comprises a device 184 for controlling the valve 180 between the closed configuration and the open configuration. The device 184 is adapted to be emanated from outside the pipe by a plunger or by a remotely operated vehicle ("ROV").

The operation of the closure member 66 shown in FIG. 17 differs from that shown in the preceding figures in that the valve 180 is actuated before the installation of the flexible line to go into the closed configuration, before the immersion of the pipe 10 in the expanse of water. Preferably, a factory test is performed on the tip 14 to verify the proper operation of the closure member 66 before the pipe 10 is installed.

Before the raising of the pipe 10, or during the ascent of the pipe 10, a plunger or remote controlled submarine vehicle approaches the nozzle 14 toat the steering device 184.

The device 184 is then actuated to pass the valve 180 of the configuration closed to the open configuration. The pipe 10 is then raised to the surface. The gas under pressure possibly present inside the pipe 10 is free to evacuate through the selective sealing element 62, for example a non-return valve and the valve 180 in the open configuration.

In a variant (not shown), the nozzle 14 furthermore defines at least one auxiliary gas evacuation route present in the flexible pipe 10 towards the outside of the flexible pipe 10, distinct from the evacuation passageway 60.

The auxiliary evacuation passage is devoid of a selective closure element 62 disposed in the auxiliary evacuation passage. The tip 14 comprises an auxiliary member for bidirectional closure of the auxiliary evacuationpass disposed in the auxiliary discharge passage and / or its outlet. The bidirectional auxiliary closure member is capable of passing from a closed configuration of closing the auxiliary discharge passage to an open configuration for evacuating a gas overpressure in the auxiliary evacuation passage. The bidirectional auxiliary closure member is identical to one of the bidirectional closure members 66 described above, in particular with respect to the figures above. It comprises, for example, a rupture disk 110. The bidirectional auxiliary locking device not being mounted in series with a selective shutter element 62, it is suitable for passing into an open configuration to prevent the bursting of the watertight sheath defining the annular space 26 to the outside in the event of failure of the selective closure element 62 or of the rise of the flexible line that is too fast (at a speed greater than that permitted by the drainage system including the selective closure element 62 and the bi-directional closure member 66 in perfect working condition).

Claims (6)

1. - Nipple (14) for connection of a flexible line, the flexible line comprising at least one tubular sheath (20) and at least one elongate element (44) disposed around the tubular sheath (20), the tip (14) comprising: - an end portion of the tubular sheath (20); an end section of each elongate element (44); - an end vault (50) and a cover (51) defining a receiving chamber (52) of each end section; the tip (14) defining at least one exhaust passage (60) of a gas present in the flexible line outwardly of the flexible line, the tip (14) comprising a selective sealing member (62) disposed in the evacuation passage (60), the selective sealing member (62) being adapted to allow the evacuation of gas through the evacuation passage (60) in the direction from the inside to the outside of the the flexible line and preventing the flow of fluid through the exhaust passage (60) beyond the selective sealing member (62) from the outside to the inside; characterized by: - at least one bi-directional closure member (66) of the discharge passage (60) disposed in and / or out of the exhaust passage (60), the bi-directional closure member (66) being adapted to moving from a closed shutoff configuration of the exhaust passage (60) to an open discharge configuration of an overpressure degass in the exhaust passage (60). 2. An end piece (14) according to claim 1, wherein at least one bidirectional closing member (66) is formed by a rupture disc (110) capable of passing from its closed configuration to its open configuration by bursting. 3. - Tip (14) according to one of claims 1 or 2, wherein the disc rupture (110) is formed of polymeric material or metal material. 4. - Tip (14) according to one of claims 2 or 3, wherein the disc rupture (110) has at least one hollow portion (160) defining at least a preferential rupture zone, of thickness less than the thickness a peripheral area of the disc disruption (110), the hollow portion (160) having a circular contour or cross-shaped. 5. - nozzle (14) according to any one of the preceding claims, comprising a transverse bearing surface (128) of the bidirectional closure member (66), arranged transversely relative to the discharge passage (60), the transverse bearing surface (128) defining a through opening (130), the tip (14) having a member (114) for plating the bidirectional closure member (66) on the transverse bearing surface (128), the bi-directional closure member (66) being secured between the transverse bearing surface (128) and the cladding member (114), relative to the through opening (130). 6. - tip (14) according to claim 5, comprising an additional support (152) interposed between the transverse bearing surface (128) and the bi-directional closure member (66) facing the through opening (130), the additional support (152) being freely mounted relative to the transverse bearing surface (128). 7. - Tip (14) according to any one of the preceding claims, whereinle at least one bidirectional closure member (66) is located downstream of the selective sealing member (62), in the direction from the inside towards the outside of the flexible line. 8. - Tip (14) according to any one of the preceding claims, whereinthe at least one bidirectional closure member (66) is located in the selective sealing member (62). 9. - Tip (14) according to claim 8, wherein theelective sealing element (62) comprises a movable valve (94), and a piercing member (172) bidirectional closure member (66), mounted movable together with the soupapemobile (94). 10. - Tip (14) according to any one of the preceding claims, whereinle at least one bidirectional closure member (66) is located upstream of the selective closure element (62), in the direction from inside towards the outside of the flexible line. 11. - Tip (14) according to any one of the preceding claims, whereinthe bidirectional closure member (66) is coaxially mounted with the selective sealing member (62). 12. - Tip (14) according to any one of the preceding claims, whereinthe at least one bidirectional closure member (66) is formed by a valve (180) operable from outside the flexible line. 13. - Tip (14) according to any one of the preceding claims, the tip (14) defining at least one auxiliary passage for discharging a gas present in the flexible line to the outside of the flexible line, separate from the evacuation passage (60), the auxiliary evacuation passage being devoid of a selective closing element (62) disposed in the auxiliary evacuation passage, the end-piece (14) comprising a bi-directional closing means of the auxiliary passage discharge device disposed in the auxiliary evacuation passage and / or at its outlet, the bidirectional auxiliary closing member being adapted to pass from a closed configuration of closure of the evacuation passenger bag to an open evacuation configuration of an overpressure of gas in the auxiliary evacuation passage. 14. - Flexible line comprising: - at least one tubular sheath (20) - at least one elongated element (44) disposed around the tubular sheath (20), - a tip (14) according to any one of the preceding claims . 15. - A method of purging a gas contained in a flexible line disposed ina body of water, the method comprising the following steps: - accumulation of gas in a flexible line according to claim 14, the bidirectional closure member (66) occupying its closed configuration; passing the bidirectional closure member (66) from its closed configuration to its open configuration; - Evacuation of the gas out of the flexible line by circulation through the evacuation pass (60), the selective shutter element (62) and the two-way closure member (66). 16. - The method of claim 15, wherein thebidirectional closing member (66) comprises a rupture member (110), thebidirectional closing member (66) passing from its closed configuration to its open configuration by breaking the organ rupture (110) under the effect of an overpressure. 17. - The method of claim 15, wherein the bi-directional closing member (66) comprises a valve (180), the bidirectional closure member (66) passing from its closed configuration to its open configuration by actuating lavanne (180). ) from outside the pipe (10). 18. - A method according to one of claims 15 to 17, wherein the gas accumulation occurs when the flexible line is disposed deep in the expanse of water, the evacuation passage (60) of the organ bi-directional closure (66) from closed configuration to its open configuration occurring before a rise of the flexible line to the surface, or when the flexible line is raised to the surface.