AU2015376145A1 - Ballasting and/or protection devices for underwater lines - Google Patents

Abstract

The invention relates to a ballasting device (10) for an underwater line (5), wherein said device has an opening (L), said opening (L) having a cross-section substantially identical to the cross-section of the outer wall of the underwater line (5), and comprises two elements (11a, 11b) arranged to engage with one another. To facilitate the on-site assembly of the ballasting device (10), the two elements (11a, 11b) engage along a pivoting link with an axis (Ap) substantially parallel to a longitudinal axis (A1) of said opening (L). The invention also relates to an associated assembly bench for the ballasting device.

Description

PCT/FR2015/050053 WO 2016/110617 1

Ballasting and/or protection devices for underwater lines

The invention relates to the field of ballasting devices and protectors including such a ballasting device. The latter are employed for all types of uses, and preferably, but non-limitingly, are applied to the positioning of umbilicals associated with wells during drilling and exploitation phases in oil deposits or fields, preferably but non-limitingly in shallow water (i.e., around twenty to forty meters deep), in the offshore field.

Today, oil, a natural mineral oil and hydrocarbon mixture, is abundantly exploited, thus being at the center of all lives, and therefore the heart of the global economy. There is also a reason that this fossil fuel source is nicknamed "black gold". In fact, oil: provides the majority of liquid fuels, including, but not limited to, LPG, fuel oil, diesel fuel, kerosene, gasoline; is the basis for many everyday objects, including, but not limited to textiles, cosmetics, fertilizers, detergents, etc., in naphtha form when produced by refining, then transformed using petrochemicals; is also included in the composition, inter alia, of asphalts, lubricants and paraffins.

Furthermore, oil has many advantages, since, being a liquid energy source, it is easy to pump, store, transport and use. Furthermore, it offers a large quantity of energy for a small volume.

Traditionally, oil is extracted using oil wells within oil fields or deposits, areas where large quantities of oil are buried, since it is a natural energy source. Such fields or deposits are located in oil-producing regions or oil basins, above or below the soil or below the ocean floor, where multiple natural oil resources or reservoirs are present. Some oilfields may extend over areas of several hundred square kilometers, requiring the presence of multiple wells to allow an entire area to be exploited. The presence of oilfields and the extraction of oil using wells make it possible to establish oil reserves.

An "oil reserve" refers to the volume or quantity of recoverable oil present in a discovered oil field or deposit discovered, taking account of the current economic and technical constraints. Conversely, an "oil resource" refers to the volume or quantity of oil present in said oil field or deposit. The current oil reserves are situated throughout most of the world, and mainly, but not exclusively, the Middle East, North and South America and Southeast Asia. Said oil reserves may also be classified using PCT/FR2015/050053 WO 2016/110617 2 various criteria, for example, but not limited to, the type of oil (conventional or nonconventional) or the likelihood of existence in the subsoil (proven, probable and possible reserves).

The exploitation of any oil deposit to obtain oil reserves is in principle made up of two major steps: first, an exploration or prospecting step, then an oil production step.

The exploration or prospecting generally consists first of looking for oil deposits, in particular by studying geological structures, then secondly of drilling, making it possible to dig a hole in particular to verify the presence of oil reserves. Once the presence of oil reserves has been proven, the second step for oil production is carried out. This production step primarily includes the extraction of the oil and may be relatively complex. In general, it is broken down into a first evaluation step followed by several recovery steps. The evaluation step primarily consists of performing a series of withdrawals. Said withdrawals consist of first studying the reservoir rock making up the reservoir by coring to evaluate various physicochemical properties of the rock, such as the permeability, porosity, then secondly studying the fluid situated within the deposit in order to measure some of its physicochemical properties, such as the composition, density, viscosity, etc. This series of withdrawals makes it possible to identify the various existing and oil-producing layers making up the deposit. The evaluation step ends with a production test seeking to define the different proportions of the fluid and thus to estimate the flow rates. The various collected information thus makes it possible to prepare a development plan for the deposit, said plan in particular including the number of oil wells to be drilled, the cost of the elements cooperating with the wells, the fluid flow rates, etc. After estimating the costs and based on the development plan for the deposit, the operators decide to commission the exploitation. The development plan may subsequently be modified throughout the entire lifetime of the field, based on the actual production.

Following the evaluation step, various recovery steps can be carried out. First of all, the primary recovery is done: due to the significant pressure present within the reservoir rock during the installation of the oil well, the oil reaches the surface independently. No other surface equipment is necessary during this primary recovery period, aside from a set of "Christmas tree" valves primarily serving to close the oil well, or a separator making it possible to extract the water from the oil.

Subsequently, over time, the oil well no longer spontaneously produces enough oil due to a decrease in the pressure within the reservoir rock of the oil deposit. The operators of the oil deposits PCT/FR2015/050053 WO 2016/110617 3 then call on two recovery steps, respectively called secondary and tertiary, which are said to be "assisted", requiring the use of different methods or additional equipments. The secondary recovery step advantageously comprises injections of different fluids, for example but not limited to water, nitrogen, or carbon dioxide, or the use of a pump: these techniques allow a significant increase in the pressure to allow the extraction of the oil. Alternatively or additionally, the tertiary recovery step seeks to decrease the viscosity of the oil or to improve the diffusion thereof within the deposit, and also includes fluid injections, for example but not limited to carbon dioxide, vapors, surfactants, etc.

The extraction step requires the use of oil wells. In the case of underwater deposits, such oil wells are used in combination with oil platforms, advantageously stationary or mobile. One non-limiting example of such a system is described in connection with figure 1. During operations on underwater oil wells, a drilling vessel or platform 1 is generally used. Such a platform 1 is, advantageously but non-limitingly, connected to a well by a large hollow tube (also called "marine riser", not shown in figure 1), said large tube in particular allowing various pieces of equipment to be lowered to the seabed, sometimes several thousand meters below the surface.

Inside said riser, a hollow tube with a small diameter allowing drilling (also called "drilling riser pipe") and an umbilical 5 are lowered. An "umbilical" refers to any cable making it possible to supply consumables to an apparatus. In the case of underwater deposits, such an umbilical 5, deployed as close as possible to the seabed SB, allows a connection with the host establishment, i.e., the platform 11, through which the necessary control orders, energy, whether electric, hydraulic or pneumatic, is transmitted, or even different chemical products delivered to an underwater oil well. Such an umbilical 5 can also be used in connection with underwater manifolds or any underwater system requiring remote control. An umbilical generally consists of a long flexible assembly of tubes, cables, etc. contained within a protective sheath: in principle, power cables for transmitting control commands and energy signals and high- or low-pressure pipesfor transporting hydraulic fluids to the control valves and chemical products for injection within the oil well are also contained within the umbilical. Such an umbilical is called "electrohydraulic cable". Furthermore, the umbilical 5 also includes other additional elements, for example, but not limited to, fiber-optic cables for monitoring purposes. The design of an umbilical is modular, adaptable to each installation: it depends on several factors, including the depth of the water, the function, the environmental conditions and the temperature. During drilling or maintenance operations, the underwater drilling line, including a drill string and/or pipe and at least one umbilical, must remain substantially stationary relative to the wellhead 6. WO 2016/110617 PCT/FR2015/050053 4

The current oilfields already produce many billions of barrels. Nevertheless, many operators are seeking to multiply said production. Indeed, installations advantageously including multiple oil wells, for example those described in connection with figure 1, are installed in order to guarantee production for years, or even decades. Nevertheless, over time, the oil wells age and become worn. Furthermore, with technological progress and development of technology, new methods are emerging making the old installations ineffective, or even obsolete, in light of the new installations currently assembled.

Today, techniques already exist for improving and boosting oil production, more particularly within underwater oilfields. Such techniques require the use of an umbilical as previously described. Depending on the functions included within the umbilical, it is possible to initiate the secondary and/or tertiary recovery steps to thus increase the pressure and/or decrease the viscosity of the fluid, in order to accelerate the oil production flow rate. Other methods consider renovating oil wells by providing electricity to said oil wells: such methods require the placement of new valves that subsequently cooperate with an umbilical.

In principle, the positioning of an umbilical requires the use of a first vessel. Upstream, different studies and cartographical readings have been done to allow a recognition operation of the beds and subsequently the positioning of the umbilical. The umbilical is then taken on board owing to the presence of a winding platform within said first vessel to allow its positioning . Once the umbilical is installed, it is necessary to stabilize it and protect it so that it can perform its role correctly, i.e., transmitting control commands or energy to the oil wells, or even conveying chemical products to said wells. Indeed, such a cable is subject to pressure and temperature differences, while the first vessel, advantageously a command and injection vessel, is subject to the weather conditions, for example but not limited to the movements of the swell. A first solution commonly used to perform stability and protection functions of an umbilical of this type consists of burying the umbilicals used in the seabed by digging a protective and dedicated underwater trench using a backfilling plow. Nevertheless, such a first solution has many drawbacks, since it requires special equipment and skills. Furthermore, it represents substantial time, since the implementation of this solution is time-consuming and tedious, consequently creating substantial additional costs. Faced with this plurality of drawbacks, the builders and operators of oil installations have sought to develop non-consumable equipment, i.e., reusable as needed, not requiring preparatory work. Thus, a second solution consists of the use of a concrete bed. A non-limiting example of such a PCT/FR2015/050053 WO 2016/110617 5 concrete bed is described in connection with figure 2. A concrete bed 7 as primarily made up of concrete modules 8, in the advantageous, but non-iimiting, form of cubes, said modules being connected to one another to form a bed. The connections between modules can be guaranteed by ropes, advantageously made from synthetic fibers, or treated steel cables: such connections thus impart a certain flexibility to the bed allowing better flexibility of use. At a predetermined distance, a predetermined number, as a function of the length of the umbilical, of concrete beds are positioned on said umbilicals to allow them not to move, but also to protect it against any flaws or interactions with other objects, for example but not limited to anchors or equivalent means, and to limit the hydrodynamic effects on the umbilical. Nevertheless, this second solution also has several drawbacks. Indeed, after the positioning of an umbilical on board a first vessel, a second vessel is necessary to convey said concrete beds, which creates substantial additional installation costs and times, since the positioning , stabilization and protection of an umbilical require the use of two vessels. Furthermore, the deployment of such concrete beds is potentially dangerous for the umbilical. Due to the substantial weight and length of the bed, specific apparatuses, such as dedicated cranes, must be used to allow the release of the bed into the sea: this release is sometimes imprecise, since there are disruptions in the seabed and the visibility several meters deep is often reduced, despite the use of appropriate robots and cameras. An incorrect calculation or incorrect manipulation to position the concrete bed could thus cause damage, or even breakage of the umbilical or other pipes optionally able to transport oil. Furthermore, said beds could also not be positioned correctly on the umbilical(s), not performing a stabilization function or a protection function. To avoid such problems, the oilfield operators most often decide to stop the production of said oilfields for the time needed to position the concrete bed, causing extremely high costs and lengthy downtimes in production.

Other devices have been developed to perform the stabilization and protection functions of an umbilical. As examples, we may in particular cite: protective devices primarily including half-shells with a predetermined length made from polyurethane and interlocking in one another; ballasted systems also made up of two half-shells nesting in one another.

Each device performs only part of the stabilization and protection functions. Furthermore, such devices have other drawbacks, since they are not preassembled and require operator expertise: substantial installation costs and heavy installation times must be provided for the use of such devices. PCT/FR2015/050053 WO 2016/110617 6

The invention makes it possible to resolve all or some of the drawbacks raised by the known solutions.

Among the many advantages provided by the ballasting device according to the invention, we may mention that it makes it possible to: propose a modular device, reusable as needed, seeing to the stability of underwater lines by adding weight, while minimizing the hydrodynamic profile of said device to avoid the appearance of additional drag forces; provide mechanical protection for the underwater lines, for example, faced with any abrasion or falls of lines; decrease the number of pieces of equipment and devices used while facilitating the installation by using preassembled devices; guarantee significant savings on installation and maintenance times and, consequently, a significant drop in costs.

To that end, in particular provided is a ballasting device for underwater lines, wherein said device has a lumen, said lumen having a cross-section substantially identical to the cross-section of the outer wall of the underwater line, including two elements arranged to engage with one another. To facilitate and accelerate the on-site assembly of the ballasting device according to the invention while decreasing the quantity of equipment, the two elements cooperate along the pivoting link with an axis substantially parallel to a longitudinal axis of said lumen.

Advantageously, the pivoting link can be embodied by a hinge.

The ballasting device according to the invention may further include fastening means arranged to maintain the elements along a section of the underwater line and encircle said section of the underwater line.

Preferably, the fastening means may include a captive screw.

To remain in position on a predetermined section of an underwater line, the elements may include means for ensuring the holding of said elements on the underwater line.

Preferably, the means for ensuring holding may include a friction pad.

Advantageously, the two elements may have an axial symmetry along a longitudinal axis of the lumen. PCT/FR2015/050053 WO 2016/110617 7

In order to adapt to the standard geometry of underwater lines, the elements may be arranged to have a lumen with a constant and circular section.

Advantageously, each element may respectively consist of a cylindrical half-shell.

To allow better penetration of the ballasting device according to the invention and have the smallest possible impact on the stability of the cable, the ends of each element have a slender shape.

Alternatively or additionally, each element of the ballasting device according to the invention respectively includes a flat.

Alternatively or additionally, to increase the lifetime of the ballasting device according to the invention, the latter may include means for controlling the corrosion of said ballasting device.

Preferably, the means for controlling corrosion may include an anode arranged to be embedded within the flat.

According to a second object, the invention relates to an assembly bench, including first and second portions arranged to engage with one another, said first portion primarily comprising an intake area of the ballasting device according to the invention, substantially planar. To allow an easier assembly and quick installation of the ballasting device according to the invention on site, the second portion comprises guide means for said ballasting device to gradually and automatically fold down the two elements of said ballasting device on a section of an underwater line.

To facilitate the use of a bench according to the invention and decrease human interventions, the first portion may comprise means for automatically conveying the ballasting device.

The invention also provides an underwater line, cooperating with one or several ballasting devices according the invention, each device encircling a section of said underwater line.

According to a third object, the invention relates to an oil-related system, including an oil-related platform, an underwater line cooperating with said platform and an oil well cooperating with said underwater line. To ensure stabilization and protection of said underwater line, the system according to the invention includes at least one ballasting device according to the invention encircling a section of said underwater line.

Other features and advantages will appear more clearly upon reading the following description and examining the accompanying figures, among which: PCT/FR2015/050053 WO 2016/110617 8 figure 1, previously described, shows a detailed view of an oil platform system for drilling; figure 2, previously described, describes an embodiment of a ballasting device according to the State of the Art in the form of a concrete bed; figures 3A and 3B provide a graphic description of the first embodiment of the ballasting device according to the invention; figures 4A and 4B schematically describe a second embodiment of the ballasting device according to the invention; figures 5A and SB describe assembly examples of the first and second embodiments of a ballasting device according to the invention; figures 6A and 6B illustrate an alternative embodiment of an assembly bench according to the invention; figures 7A to 7D show different views of an embodiment of an assembly bench according to the invention.

Figures 3A and 3B schematically show a first embodiment of a ballasting device according to the invention, in the closed and open positions, respectively. A ballasting device 10 for an underwater line 5 according to the invention advantageously has a lumen L. Such a ballasting device 10 advantageously allows the stabilization and protection of an underwater line 5, said underwater line being integrated into a drilling system, such as, but not limited to, that described in connection with figure 1. Preferably, such an underwater line may consist of an umbilical, as previously described, but cannot be limited to this example alone: it may consist of any cable or pipe advantageously engaging with an oil platform and an oil well. "Lumen" refers to any central orifice or cavity arranged in the ballasting device in order to allow the passage of an underwater line therein. Thus, said lumen L advantageously has a section substantially identical to the section of the outer wall of the underwater line 5: said section can advantageously be square, circular, oblong or have any other section may be adapted for an underwater line, or even in some cases several underwater lines. Furthermore, preferably, the device 10 includes two elements 11a, lib arranged to engage with one another: the lumen L is thus defined when the ballasting device 10 according the invention is in the closed position, i.e., the elements 11a and lib engage with one another, such that they are fastened to one another using any means, situation described in connection with figure 3A. Nevertheless, the device 10 may include three, four, or even a plurality of elements, engaging with one another, in pairs. Each PCT/FR2015/050053 WO 2016/110617 9 element advantageously includes a ballast to allow the stabilization of the underwater line. "Ballast" refers to any heavy body ensuring the movement of the center of gravity or the increase in the mass of the underwater line to ultimately guarantee said stabilization. By way of non-limiting examples, such a ballast may consist of the use of a particular material, such as cast-iron, an alloy of iron and carbon, or the integration of the ballast within said elements.

Such elements 11a, lib engage according to a pivoting link, i.e., they are mounted rotating relative to one another. Such a pivoting link thus makes it possible to guide the two elements 11a, lib in rotation around the connecting axis and block any other degree of freedom, in particular the translational movement. Advantageously, the pivoting link is made along an axis Ap substantially parallel to a longitudinal axis Al of the lumen L. "Longitudinal axis" A means, by way of non-limiting examples, when the elements 11a, lib are arranged so that the lumen L has a circular and constant section as described in connection with figure 3A, the axis Ap of the pivoting link may be substantially parallel to the axis of revolution of the lumen L. Alternatively, when the elements 11a, lib are arranged so that the lumen L has a square and constant section, the axis Ap of the pivoting link may be substantially parallel to the axis passing through the center of the square, section of the lumen L. Advantageously, but non-limitingly, the pivoting link can be embodied by a hinge 12. Such a hinge 12 makes it possible to install the ballasting device 10 quickly and with a minimum number of different parts. For all useful purposes, a plurality of hinges may be provided, in particular along the length of the elements 11a, lib. The hinge is a mechanical member allowing the articulation of two rotating elements along a pivoting link. In principle, such a hinge is made up of three parts: the first part, immobile, corresponds to the hinge plate and can be fastened on the element 11a, the second intermediate part corresponds to the hinge pin serving as axis, and lastly, the third moving part corresponds to the hinge and can be fastened on the element lib. Any other equivalent system allowing the implementation of such a pivoting link, for example but non-limitingly a rotation axis, a connecting rod including the pivoting link, can also be used. The invention cannot be limited to the use of a single pivoting link. The cooperation of the elements 11a, lib can be ensured using a double pivoting link or several combined pivoting links if necessary.

Furthermore, the ballasting device 10 according to the invention can include fastening means arranged to maintain the relative position of the elements 11a, lib along a section of the underwater line 5 and to encircle said section of the underwater line. The fastening means guarantee the cohesion of the ballasting device 10 around the underwater line, in the closed position, situation described in connection with figure 3A. Such fastening means can advantageously comprise any bolts, fastening PCT/FR2015/050053 WO 2016/110617 10 screws or equivalent means allowing the tightening or locking of the two elements 11a, lib and their fasteners. Alternatively or additionally, the fastening means can include one or several captive screws 13. Such captive screws have many advantages, since they make it possible to obtain a captive screwing function. Indeed, during mounting operations, a screw can easily escape an operator's hands, which may have serious consequences, in particular involving the safety of the said operator and/or slowing the assembly process of said ballasting device. According to figures 3A and 3B, such captive screws can advantageously be integrated within one of the elements 11a and lib. Additionally, one or several orifices or recesses 13o, depending on the number of captive screws included in the ballasting device, are arranged in the other of the elements 11a or lib, in order to accommodate said captive screws 13. Preferably but non-limitingly, the fastening means consist of two locking screws in order to ensure the fastening of the ballasting device 10 in case of failure of one or the other of said screws.

During the positioning of said device on the underwater line, the fastening of the latter may prove more or less effective: if the locking of said device is not appropriate due to the fact that it is too lax, the ballasting device may optionally slide along the underwater line, which may also cause the system to lose stability. Conversely, when the elements of the ballasting device are fastened by excessively compressing the underwater line, they may damage the integrity of the latter. To resolve this drawback, the elements 11a, lib of a ballasting device according to the invention may include means for ensuring the holding of said elements on the underwater line. Preferably, but non-limitingly, the means for ensuring holding may include a friction pad 17. Such a friction pad 17, also known as a "nonslip pad", may advantageously be made from a material suitable for decreasing, slowing, or even completely stopping the relative movements between the elements 11a, lib of the ballasting device and the underwater line, more particularly the outer wall of the latter. Said friction pad may also make it possible to decrease the compression applied on the underwater line in order to grip said line without damaging it. According to figure 3B, one or several friction pads 17 may advantageously be positioned on the inner wall of one or both elements 11a, lib, so as to engage according to an embedding link. Said friction pad 17 can be permanent or removable.

As previously specified, the two elements 11a, lib include or consist of a ballast to aliow the stabilization of the underwater line. In order to allow lasting stabilization of the underwater line, the two elements 11a, lib may have an axial symmetry along a longitudinal axis Al of the lumen L: such a configuration allows a better distribution of weight. Additionally, said elements 11a, lib can PCT/FR2015/050053 WO 2016/110617 11 advantageously be identical. By way of non-limiting example, in connection with figures 3A, the section of the lumen L being circular and constant, the elements 11a, lib have an axial symmetry along the axis of revolution of the lumen L. Preferably, each element 11a, lib may respectively consist of a cylindrical half-shall, as described in connection with figures 3A and 3B. Such a particular form advantageously makes it possible to fit the typical outer walls of the underwater lines. Furthermore, such elements 11a, lib have traditional forms commonly manufactured and used in the offshore field. Such half-shells are considered to be particularly suitable for improving the stability of the underwater line.

Additionally, each element 11a, lib may have a particular hydrodynamic profile, having the smallest possible impact on the stability of the underwater line 5 and the associated ballasting device. Among a non-exhaustive set of changes of the hydrodynamic profile of each element 11a, lib, the invention sets out that: the outer ends 16 of each element 11a, lib can have a slender shape and consequently, the ends of the ballasting device 10 according the invention may have a conical shape: the sections of the ends are smaller. Such a profile makes it possible to facilitate the passage in the pieces of equipment for positioning said ballasting device and said underwater line in the water; the inner ends of each element 11a, 11b can have a slightly flared shape to guarantee unencumbered flexural movements of the underwater line as needed; one or several elements 11a, lib can have a bevel or chamfer, i.e., a small surface formed by a pitched rim or obliquely shaped edge, in order to increase the stability of the ballasting device according to the invention before and after the installation on the underwater line; each element 11a, 11b can respectively include a flat 15.

Once installed on the underwater line, the ballasting device is provided to stay for several years, or even several decades on the seabed. The materials used to manufacture said device are not always appropriate for this type of use. As a result, additionally, the ballasting device 10 according to the invention may include means for monitoring the corrosion of said ballasting device. Preferably but non-limitingly, the means for controlling corrosion may include an anode 14 arranged to be "embedded", i.e., inserted, within the flat 15. Such an anode can be of the sacrificial type, i.e., it will be made up of a metal more reducing than the metal to be protected making up the elements 11a, 11b to ensure the dissolution and/or oxidation of said anode before that or those of said elements. By way of non-limiting example, such an anode may advantageously be made up of an aluminum alloy. WO 2016/110617 PCT/FR2015/050053 12

Figures 4A and 4B schematically show a second embodiment of a ballasting device according to the invention.

Like figures 3A and 3B, such a ballasting device 10 for an underwater line 5 advantageously has a lumen L. Such a ballasting device 10 advantageously allows the stabilization and protection of an underwater line 5, said underwater line being integrated into a drilling system, by way of non-limiting example, that described in connection with figure 1. Preferably, such an underwater line may consist of an umbilical as previously described, but cannot be limited to this example alone: it may consist of any cable or pipe advantageously engaging with an oil platform and an oil weil. Thus, said lumen L advantageously has a section substantially identical to the section of the outer wall of the underwater line 5: said section may advantageously be square, circular, oblong, or have any other section that may be adapted for an underwater line. Furthermore, preferably, the device 10 includes two elements 11a, lib arranged to cooperate with one another: the lumen L is thus defined when the ballasting device 10 according the invention is in its dosed position, i.e., the elements cooperate with one another, such that they are fastened to one another by any means, situation described in connection with figure 3A. Nevertheless, the device 10 may include three, four, or even a plurality of elements, cooperating with one another in pairs. Each element advantageously includes a ballast to allow the stabilization of the underwater line. By way of non-limiting examples according to figure 4A, the ballast 18 can be "embedded", i.e., covered with a suitable material, to avoid any corrosion phenomenon and a resulting loss of mass and stability, in place of the anode used in the first embodiment of the device according to the invention: said ballasting device would thus have a limited lifetime. By way of preferred but nonlimiting example, polyurethane can be used to cover said ballast: the ballast 18 is advantageously presented in the form of an insert.

Such elements 11a, lib cooperate according to a pivoting link, i.e., they mounted rotating relative to one another. Such a pivoting link thus makes it possible to guide the two elements 11a, lib in rotation around the connecting axis and to block any other degree of freedom, in particular translational movement. Advantageously, the pivoting link is made along an axis Ap substantially parallel to the longitudinal axis Al of the lumen L. "Longitudinal axis" A means, by way of non-limiting examples, when the elements 11a, lib are arranged so that the lumen L has a circular and constant section as described in connection with figure 4B, the axis Ap of the pivoting link may be substantially parallel to the axis of revolution of the lumen L. Alternatively, when the elements 11a, lib are arranged so that the PCT/FR2015/050053 WO 2016/110617 13 lumen L has a square and constant section, the axis Ap of the pivoting link may be substantially parallel to the axis passing through the center of the square, section of the lumen L. Advantageously but non-limitingly, the pivoting link may be embodied by a hinge 12. Such a hinge 12 makes it possible to install the ballasting device 10 quickly and with a minimal number of different parts. For all useful purposes, a plurality of hinges may be provided, in particular along the length of the elements 11a, lib. By way of preferred, but non-limiting example, the use of an elastic hinge is favored over the use of a screw hinge. Any other equivalent system allowing the implementation of such a pivoting link, for example but not limited to a rotation axis, a connecting rod including a pivoting link, could also be used. The systems used to embody said pivoting link can be identical or similar to those used in the ballasting devices according to the first embodiment.

Furthermore, the ballasting device 10 according to the invention may include fastening means arranged to maintain the relative position of the elements 11a, lib along a section of the underwater line 5 and to encircle said section of the underwater line. The fastening means guarantee the cohesion of the ballasting device 10 around the underwater line, in the closed position, situation described in connection with figure 3A. Such fastening means can advantageously comprise any bolts, fastening screw or equivalent means making it possible to grip or lock two elements 11a, lib and their fasteners. Alternatively or additionally, the fastening means can include one or several metal strips, bands serving to keep said elements 11a, lib locked together. Said strips may advantageously be made from stainless steel or an appropriate alloy making it possible to avoid any corrosion phenomena.

As previously specified, the two elements 11a, lib include or consist of a ballast to allow the stabilization of the underwater line. In order to allow a lasting stabilization of the underwater line, the two elements 11a, lib may have an axial symmetry along a longitudinal axis Al of the lumen L: such a configuration allows a better weight distribution. Additionally, said elements 11a, lib may advantageously be identical. As a non-limiting example, in connection with figures 4A and 4B, the section of the lumen L being circular and constant, the elements 11a, lib have an axial symmetry along the axis of revolution of the lumen L. Preferably, each element 11a, lib may respectively consist of a cylindrical half-shell, as described in connection with figures 4A and 4B. One such particular form advantageously makes it possible to fit the typical outer walls of the underwater lines. Furthermore, such elements 11a, lib have traditional forms commonly manufactured and used in the offshore field. Such half-shells are considered to be particularly suitable for improving the stability of the underwater PCT/FR2015/050053 WO 2016/110617 14 line. Additionally, the ballast 18 may advantageously have a profile with a double curve so as not to hinder any curvature movements of the underwater line.

In some cases, the sections of the underwater line to be protected and stabilized can have different lengths, depending on the depth in which the sections are positioned. As a non-limiting example, when the underwater line is positioned on the seabed, the line sections to be protected are much larger. Thus, according to figures 4A and 4B, the ballasting device 10 according to the invention may include attachment means 19 making it possible to interconnect the different successive ballasting devices and ensure continuous protection and stabilization of the underwater line. Advantageously but non-limitingly, such attachment means may include corresponding male-female devices.

Figures 5A and 5B illustrate assembly examples of first and second embodiments of a ballasting device according to the invention.

Such a ballasting device 10 according to the invention is advantageously mounted crimped on an underwater line 5 such that said ballasting device 10 encircles said underwater line 5. The underwater line 5 occupies the empty space defined by the lumen L of each ballasting device 10. The invention provides that a plurality of ballasting devices 10 are used in series on the underwater line 5 to ensure the stabilization and protection of the various sections of the underwater line 5, said sections being able to have different lengths. Such ballasting devices 10 may thus guarantee the positioning of modular systems, adaptable according to the needs and types of underwater lines. According to said needs, the ballasting devices may be assembled on sections of successive underwater lines, situation described in connection with figure 5B, or on sections of separate underwater lines, situation described in connection with figure 5A.

Figures 6A and 6B illustrate an alternative embodiment of an assembly bench according to the invention. Such a bench makes it possible to assemble a ballasting device according to the invention and an underwater line in a minimal amount of time on site. It is advantageously positioned on the platform or the vessel allowing the installation of an underwater line.

Said bench 30 advantageously includes first and second portions 31 and 32, respectively, arranged to engage with one another. According to figure 6A, said portions advantageously engage using an embedding link, allowing permanent or removable fastening of the first and second portions. Alternatively, the first and second portions can form a single and same entity. The first and second PCT/FR2015/050053 WO 2016/110617 15 portions 31 and 32 can advantageously have an upside down "L" shape, allowing space savings within the vessel and easier assembly.

Said first portion primarily comprises an intake area of the ballasting device according to the invention that is substantially planar, making it possible to convey said device up to the underwater line for assembly, said underwater line being in motion along the second portion. During its passage within the first portion, the ballasting device according the invention is advantageously in the initial position, situation described in connection with figures 6A and SB. The "initial position" is defined as the position in which the elements 11a, lib, making up the ballasting device, are substantially comprised in a same plane. Additionally, the first portion 31 may advantageously include guide means to prevent the ballasting device, when it is conveyed along this portion, from leaving its trajectory. Such guide means can advantageously comprise two bars positioned along transverse walls of the first portion at a sufficient height to contain said device. Any equivalent system may also be used. Furthermore, the first portion 31 may also include "automatic" conveying means allowing the arrival of the device within the second portion 32 without human intervention. Such conveying means 31c can advantageously comprise a roller conveyor, conveyor belt or any other equivalent means without limiting the scope of the present invention.

The second portion 32 allows the "automatic" assembly of the ballasting device according to the invention around the underwater line. As previously specified, the ballasting device 10 according to the invention is advantageously mounted crimped on an underwater line 5 such that said ballasting device 10 encircles a section of said underwater line 5. It is thus necessary to facilitate said assembly, since the installation and positioning operations of the underwater lines and their equipment take place in line. The assembly bench is designed to facilitate the installation through the use of preassembled devices. According to figure 6A, an underwater line 5 is advantageously unwound along the second portion 32, in order to allow the assembly of the ballasting devices around said line. Said underwater line 5 follows a continuous longitudinal movement to allow its positioning on the seabed in particular. Such a movement can be initiated using a suitable winch or any equivalent system, advantageously positioned within the vessel. The continuous movement of the underwater line 5 drives the ballasting device 10 according to the invention, when one or several elements 11a, 11b of the device come into contact with said line. Such driving is in particular related to figures 7A to 7D, said figures showing different views of an alternative embodiment of an assembly bench according to the invention in different positions within the second portion 32. Additionally, like the first portion 31, said second portion may comprise PCT/FR2015/050053 WO 2016/110617 16 "automatic" conveying means to facilitate the driving of the ballasting device along the second portion 32. Such conveying means 32c can advantageously comprise a roller conveyor, conveyor belt or any other equivalent means without limiting the scope of the present invention.

To allow easier assembly and quick installation of the ballasting device on site, while minimizing human interventions, the second portion 32 comprises guide means 33 for said ballasting device to gradually and automatically fold the elements down over a section of an underwater line. Such guide means 33 are advantageously positioned along transverse walls of the second portion at a sufficient height to contain said device. The distance between the guide means 33 decreases along the second portion 32, as described in connection with figures 6A, 7A and 7B, in order to guarantee the assembly of the device around the underwater line 5. By way of non-limiting examples, said guide means 33 can advantageously comprise two bars or any other equivalent system. The guide means 33 could also be made up of a trough, advantageously arranged within the second portion 32. Additionally, the second portion may also comprise means 34 allowing the locking of a fastening means present on the ballasting device 10, as described in connection with figures 7C and 7D, said means 34 being arranged successively with respect to the guide means 33. As previously specified, the fastening means can be present, such fastening means being arranged to maintain the relative position of the elements 11a, lib along a section of the underwater line 5 and to encircle said section of the underwater line and thus guarantee the cohesion of the ballasting device 10 around the underwater line 5, in the closed position.

The invention also provides an oil-related system, including an oil-related platform, an underwater line cooperating with said platform and an oil well cooperating with said underwater line. To decrease the costs and installation time of the system, said system includes at least one ballasting device according to the invention encircling a section of said underwater line. Said oil-related platform can advantageously be stationary or movable, or can even constitute a floating unit. The invention cannot be limited to the type of platform included by said system.

The invention has been described during its use in connection with the positioning of umbilicals associated with wells in oil deposits or fields. It can also be implemented for all types of underwater lines that require stabilization and protection functions.

Other modifications may be considered without going beyond the scope of the present invention defined by the appended claims.

Claims (17)

1. A ballasting device (10) for an underwater line (5), having a lumen (L), said lumen (L) having a section substantially identical to the section of the outer wall of the underwater line (5), including two elements (11a, lib) arranged to cooperate with one another, said device (10) being characterized in that said two elements (11a, lib) cooperate according to a pivoting link with axis (Ap) substantially parallel to a longitudinal axis (Al) of said lumen (L).

2. The ballasting device (10) according to the preceding claim, wherein the pivoting link is embodied by a hinge (12).

3. The ballasting device (10) according to any one of the preceding claims, further including fastening means arranged to maintain the relative position of the elements (11a, lib) along a section of the underwater line (5) and to encircle said section of the underwater line.

4. The ballasting device (10) according to the preceding claim, wherein the fastening means include a captive screw (13).

5. The ballasting device (10) according to any one of the preceding claims, wherein the elements (11a, lib) include means for ensuring holding of said elements on the underwater line.

6. The ballasting device (10) according to the preceding claim, wherein the means to ensure the holding include a friction pad (17).

7. The ballasting device (10) according to any one of the preceding claims, wherein the two elements (11a, lib) have an axial symmetry along a longitudinal axis (Al) of the lumen (L).

8. The ballasting device according to any one of the preceding claims, wherein the elements (11a, lib) are arranged to have an lumen (L) with a constant and circular section.

9. The ballasting device according to the preceding claim, wherein each element (11a, lib) respectively consists of a cylindrical half-shell.

10. The ballasting device according to the preceding claim, wherein the ends (16) of each element (11a, lib) have a slender shape.

11. The ballasting device (10) according to any one of claims 8 to 10, wherein each element (11a, lib) respectively include a flat (15).

12. The ballasting device (10) according to any one of the preceding claims, including means for monitoring the corrosion of said ballasting device.

13. The ballasting device (10) according to claims 11 and 12, wherein the means for monitoring the corrosion include an anode (14) arranged to be embedded within the flat (15).

14. An assembly bench, including first and second portions arranged to cooperate with one another, said first portion primarily comprising an intake area of the ballasting device according to any one of claims 1 to 13 that is substantially planar, said bench being characterized in that the second portion comprises guide means for said ballasting device to gradually and automatically fold down the two elements (11a, lib) of said ballasting device (10) on a section of an underwater line (5).

15. The assembly bench (30) according to the preceding claim, wherein the first portion (31) comprises means (31c) for automatically conveying the ballasting device (10).

16. An underwater line (5), cooperating with one or several ballasting devices (10) according to any one of claims 1 to 13, each device (10) encircling a section of said underwater line (5).

17. An oil-related system, including in oil-related platform (1), an underwater line (5) cooperating with said platform (1) and an oil well (6) cooperating with said underwater line (5), said system being characterized in that it includes at least one ballasting device (10) according to any one of claims 1 to 13 encircling a section of said underwater line (5).