System for plating a section of the sealing membrane of a storage tank

Abstract

Title of the invention: Cladding system for a portion of a sealing membrane of a storage tank The present invention relates to a cladding system (17) for a portion of a sealing membrane (10) comprising a plate device (18) and a retention system (40), the plate device (18) comprising a first plate (20), a second plate (22) and at least one compression member (28, 28A, 28B), the plate device (18) being configured to have a compressed configuration in which the compression member (28, 28A, 28B) is subjected to a compression force about the vertical axis (V), and a cladding configuration in which the compression member (28, 28A, 28B) is subjected to an extension force about the vertical axis (V) allowing the second plate (22) to be cladding against the retention system (40) and the first plate (20) against the portion of the sealing membrane (10). Figure from the summary: Figure 1

Description

Title of the invention: System for plating a portion of the waterproofing membrane of a storage tank

[0001] The present invention relates to the field of tanks intended for the storage of liquefied gases, and more particularly to the means for ensuring the sealing of such tanks.

[0002] Liquefied gases, for example liquefied natural gas, liquefied petroleum gas, ethane, ammonia or hydrogen, are important sources of energy. These liquefied gases are generally stored in suitable tanks in the liquid state, at a temperature close to -160°C for liquefied natural gas. They then occupy a reduced volume compared to the volume they would occupy in the gaseous state. This facilitates the transport of these liquefied gases between an extraction site and a destination site. For the purpose of their transport and during this transport, the liquefied gases are stored in sealed and thermally insulating tanks. Such tanks can be installed on land or on a floating structure.

[0003] The sealing and thermal insulation of the walls of the tanks are essential to ensure proper storage of liquefied gases. These walls are formed of panels which thus comprise at least one layer of thermal insulation covered by a sealing membrane. The panels may in particular have a primary layer comprising a layer of thermal insulation and a sealing membrane, and a secondary layer comprising a layer of thermal insulation and a sealing membrane intended to be in contact with the liquefied gas.

[0004] Between two adjacent panels, it is necessary to ensure the continuity of the seal. For this purpose, it is possible to use a sealing portion intended to cover and, if necessary, fill a space between the two adjacent panels. The sealing portion is secured to the wall it is intended to equip by gluing. Such gluing is generally done by hand, because it concerns areas that are difficult to access for bulky machines. During this gluing, it is necessary to allow a waiting time for the glue to crosslink and be inserted between the fibers of the wall. The sealing portion must be kept in position during this waiting time and the glue must be heated to temperatures of the order of 60 or 70 °C.

[0005] Devices are known from the prior art for applying pressure to the sealing portion to hold it in position for an appropriate period of time at the end of the bonding operation, this pressure being ensured by the presence of an air balloon. A plurality of devices is installed along the areas of sealing portions to be bonded, their respective balloons each being connected to a manifold which is itself connected to a main air supply. However, hoses managing the connections are likely to break and / or the air supply may malfunction, which has the effect of generating a pressure differential during the bonding operation. However, in the event of poor bonding, it is necessary to dismantle the wall, sand down the previously applied glue and then repeat the operations for the entire area supplied by a manifold, which is particularly tedious.

[0006] The present invention aims to overcome this drawback by proposing a pressurizing device which is easy to install and in which the risks of breakage are reduced and the pressure is easily controlled.

[0007] The main object of the present invention is thus a system for plating a portion of the sealing membrane of a wall of a liquefied gas storage tank, comprising a plate device and a retaining system capable of being fixed to the wall covering a receiving cavity of the wall capable of receiving the plate device, the plate device comprising: - a first plate intended to be positioned opposite the portion of waterproofing membrane; - a second plate arranged substantially parallel to and at a distance from the first plate relative to a vertical axis; - a reception space delimited between the first plate and the second plate which extends mainly along a plane perpendicular to the vertical axis; - at least one compression member arranged in the receiving space; the plate device being configured to have a compressed configuration in which the compression member undergoes a compression force along the vertical axis making it possible to place the plate device in the receiving cavity, and a pressing configuration in which the compression member undergoes an extension force along the vertical axis making it possible to press the second plate against the retaining system and the first plate against the portion of sealing membrane.

[0008] The plating system according to the invention is intended to be implemented in a liquefied gas storage tank, for example the tank of a ship, with a view to installing a portion of a sealing membrane for a wall of this tank. The liquefied gas is for example liquefied natural gas or liquefied petroleum gas, or ethane, methane, ammonia, nitrogen (dinitrogen) or hydrogen (dihydrogen), in their liquid form. The portion of sealing membrane is for example a flexible secondary barrier. The portion of sealing membrane is intended to be bonded to a thermally insulating layer participating in forming the wall of the tank, the plating device allowing the portion of sealing membrane to be bonded to the thermally insulating layer. The portion of sealing membrane is notably used in a junction zone between two panels forming the walls of the tank, these panels being composed of a primary layer comprising a first thermal insulation layer and a first waterproofing membrane, and a secondary layer comprising a second thermal insulation layer and a second waterproofing membrane. The portion of waterproofing membrane is in particular a part of the secondary layer affixed between the primary layers of two adjoining panels.

[0009] The plating system comprises a plate device which comprises two plates delimiting between them a receiving space. This receiving space constitutes a housing for at least one compression member of the plate device. The receiving space is further intended to be successively filled and emptied of air in particular to generate compression and a corresponding return effect of the compression member, so that the latter participates in ensuring effective and constant plating of the portion of waterproofing membrane against the secondary layer.

[0010] The plate device is configured to take at least two different configurations during its use, which depend on a conformation of the compression member governed by a compression force on the one hand and an extension force on the other hand. In particular, the deformation undergone by the compression member due to the vacuum corresponds to the exertion of the compression force, while the deformation resulting from the elastic return effect corresponds to the exertion of the extension force.

[0011] Throughout the application, mention is made of a compression force which tends to bring the plates closer together and an extension force which tends, on the contrary, to move the plates apart. This implies different configurations of the plate device in which the compression member(s) experience a compression ratio specific to a given configuration. Mention is made of compression ratio of the compression member to refer to the deformation undergone by the latter under the effect of a vacuum, which tends to compress it and reduce its dimension in the compression direction to a minimum, and under the effect of elastic return, which tends to extend it and restore it to a dimension close to its dimension at rest.The compression ratio is calculated by considering the dimension of the compression member along the compression direction and by making a ratio between this dimension at rest and the active dimension in a given configuration of the compression member. The compression ratio is notably calculated by dividing the difference between the dimension at rest and the active dimension by said dimension at rest. The absolute value of this compression ratio is then considered and it is considered high if it is greater than 50% and low if it is less than 50%.

[0012] In a rest configuration of the plate device, the compression member is in its rest position. Such a rest position corresponds to a compression rate zero pressure of the compression member, i.e. of the order of 0%. The first plate and the second plate then have a maximum distance from each other. The rest configuration is a configuration in which the plate device is, for example, moved within the tank in order to position it against the portion of the sealing membrane.

[0013] In the compressed configuration of the plate device, the compression member undergoes a compression force along the vertical axis, that is to say an axis perpendicular to the plates. In other words, the compression member has a so-called maximum compression rate, for example greater than 90%, or even a compression rate of 100%. In this compressed configuration, the first plate and the second plate are as close as possible to each other. In other words, a force is exerted on the compression member such that the plates move closer to each other, in the direction of the inside and vertically of the plate device. This makes it possible to reduce the size of the plate device with a view to its installation within the receiving cavity of the wall or its removal therefrom, in particular in order to facilitate its installation and / or its uninstallation relative to the retaining system.

[0014] This retaining system is intended to serve as a displacement stop for the plate device to keep the latter in position throughout the time required for bonding, and more particularly by constraining it so that the return force of the compression member tends to push the first plate against the portion of sealing membrane. It constitutes a stop against which the second plate pushes due to the return effect of the compression member and the fact that air can again enter the housing, which tends to separate the plates from each other.

[0015] In the plating configuration of the plate device, the compression member undergoes an extension force along the vertical axis, in a direction opposite to that of the compression force mentioned above. In other words, the compression member has a compression rate lower than the compression rate of the compressed configuration. The compression member has, for example, a compression rate of between 1 and 99%. This plating configuration, which may correspond to a different compression rate depending on the type of tank on which the system according to the invention is used, corresponds in particular to the configuration during which the plating device optimally performs the work of plating the portion of the sealing membrane.The first plate is then in contact with the portion of the sealing membrane; it is more particularly pushed against it due to the compression member which relaxes to return to its rest configuration, which separates the two plates from each other. It is understood from the above that the plating configuration is an intermediate configuration between the configuration of . rest and the compressed configuration. The plating configuration is the stable configuration in which the separation of the plates from each other is stabilized, the plates being respectively in contact with the portion of waterproofing membrane and the retaining system and pushed away from each other by entering the receiving space. In other words, a force is exerted by the compression member such that the plates move away from each other, in the outward and vertical direction of the plate device.

[0016] The presence of the retaining system makes it possible to ensure effective pressure on the portion of the sealing membrane, this retaining system preventing the plate device from being released from the receiving cavity within which it has been positioned. There is thus no possible hydraulic rupture as was the case with the devices of the prior art equipped with air balloons; here, due to the return effect of the compression member, there is an assurance of constant pressure on the portion of the sealing membrane until the retaining system is removed.

[0017] According to an optional feature of the invention, the plating system comprises a vacuum system configured to place the plate device in its compressed configuration.

[0018] The vacuum system is for example a Venturi system. It is configured to suck the air present within the receiving space in the rest configuration of the plate device, prior to the installation of the plate device against the portion of waterproofing membrane to be bonded, or to suck the air present within the receiving space in the plating configuration, prior to the uninstallation of the plate device while the retaining system is still in place on the wall. As the vacuum is applied, the two plates move closer to each other and the plate device thus passes from the rest configuration or the plating configuration to the compressed configuration.In other words, the vacuum system participates on the one hand in the installation of the plate device, by making it pass from its rest configuration to its compressed configuration, and on the other hand in its disassembly, by making it pass from its plating configuration to its compressed configuration.

[0019] According to an optional characteristic of the invention, the second plate comprises at least one orifice for receiving the vacuum system.

[0020] The second plate corresponds to a portion of the plate device at a distance from the portion of sealing membrane, against which the first plate is intended to be pressed. This second plate is in contact with the retaining system in the pressing configuration. The receiving orifice provided within the second plate is an orifice through which air is sucked when the vacuum system is put into operation. It is understood that the vacuum system is po located opposite the second plate, a portion of this vacuum system being for example introduced through the orifice to the receiving space to suck out the air present within the receiving space.

[0021] According to an optional characteristic of the invention, the retaining system comprises at least one retaining member arranged to bear against the second plate and intended to be fixed to the wall of the storage tank.

[0022] Thus, the retaining system makes it possible to limit a receiving housing of the plate device and to form a stop for the second plate against the retaining member, which has the effect on the one hand of preventing the plate device from being released and on the other hand of creating a support point so that the return effect tends to press the first plate against the portion of sealing membrane. Thus, the retaining member is intended to form a movement stop against the second plate when the plate device assumes its pressing configuration. More particularly, when the plate device moves from its compressed configuration to its pressing configuration, the compression member pushes the first plate against the portion of sealing membrane and the second plate against the retaining system or the retaining member, which has the effect of pressing the first plate against the portion of sealing membrane.The retaining member is, for example, a beam or a reinforcement bar.

[0023] According to an optional characteristic of the invention, the plate device comprises at least one sealing member closing the receiving space.

[0024] The sealing member is for example a seal. It helps to delimit, with the plates, the receiving space while preventing air leaks.

[0025] According to an optional characteristic of the invention, the sealing member is arranged on a periphery of the plate device.

[0026] The sealing member is, depending on the embodiments, arranged between the first plate and the second plate, or it is arranged around them.

[0027] Alternatively, the sealing member is inserted into receiving zones provided for this purpose between the first plate and the second plate.

[0028] According to an optional characteristic of the invention, the plate device comprises at least one first compression member and one second compression member extending parallel along a longitudinal axis perpendicular to the vertical axis. It is understood that the first compression member and the second compression member correspond to the at least one compression member mentioned above.

[0029] The first compression member and the second compression member are then arranged side by side between the two plates. The presence of two compression members makes it possible to distribute the compression forces within the plate device.

[0030] According to an optional characteristic of the invention, the orifice is arranged between the first compression member and the second compression member.

[0031] The orifice is in a central portion of the plate device, the first compression member and the second compression member being arranged on either side of this orifice. The positioning of the orifice in the central portion makes it easier to connect it to the vacuum system.

[0032] According to an optional characteristic of the invention, the receiving space comprises at least one housing within which the compression member is arranged. The housing has the function of preventing the compression member from moving within the receiving space.

[0033] In some embodiments, the receiving space further comprises a channel communicating between the housing and the receiving orifice of the vacuum system. Where appropriate, the channel communicates with both housings of the two compression members and the orifice.

[0034] According to an optional characteristic of the invention, the plate device comprises at least one member for blocking a longitudinal movement of the compression member.

[0035] The locking member constitutes a stop for the compression member. It makes it possible to prevent its longitudinal displacement during its compression and / or decompression. In certain embodiments, the plate device comprises two locking members each disposed at one of the longitudinal ends of the compression member.

[0036] According to an optional characteristic of the invention, the compression member is a spring blade extending from one longitudinal end to the other of the plate device.

[0037] A spring setting makes it possible to control the pressure applied during compression of the compression member.

[0038] According to an optional feature of the invention, the first plate and the second plate are made of wood, plastic or metal. It should be understood that the plates must be sufficiently rigid so as not to deform and to maintain a substantially flat general configuration, whether under the effect of the vacuum or the pressure exerted by the compression member during its expansion.

[0039] The invention also relates to a use of a plating system as mentioned, in which the plating system is used to hold the portion of sealing membrane in position while it is being bonded to the wall of the liquefied gas storage tank.

[0040] The invention further relates to a method for plating a portion of sealing membrane of a wall of a liquefied gas storage tank using a plating system as mentioned above, comprising a compression step during which the plate device passes into its configuration compressed, a positioning step during which the plate device is placed so that the first plate is in contact with the portion of waterproofing membrane, a positioning step during which the retaining system is positioned against the wall and a pressing step in which the plate device changes from its compressed configuration to its pressing configuration.

[0041] The plating method according to the invention makes it possible to perform plating on the portion of waterproofing membrane during the time necessary for its bonding. To do this, the plating method comprises a step of compressing the plate device, using the vacuum system, to compress the compression member so that the plate device can be installed. This is followed by a positioning step during which the first plate is placed opposite the portion of waterproofing membrane. The method further comprises a positioning step during which the retaining system is installed against the wall.It should be noted that this step of positioning the retaining system may take place after the step of positioning the plate device opposite the portion of waterproofing membrane, with the retaining system covering the plate device within the receiving cavity, or may take place before this positioning step and where appropriate before the step of compressing the plate device. In the latter case, the plate device in its compressed configuration is slid between the retaining system and the portion of waterproofing membrane. The method then comprises a pressing step during which the first plate is pressed against the portion of waterproofing membrane due to the plate device passing into its pressing configuration, the compression member moving the first plate and the second plate apart from each other by relaxing.The plate device is then held in position using the retaining system, which forms a stop against the second plate and this stop helps to increase the pressing force against the portion of the sealing membrane on the opposite side of the plate device.

[0042] According to an optional characteristic of the invention, during the compression step, air present in the receiving space is sucked in by the vacuum system.

[0043] The suction of the air contained in the receiving space by means of the vacuum system has the effect of compressing the compression member. The vacuum system makes it possible, for example, to place the plate device under a pressure of between 300 and 400 mbar, a pressure which makes it possible to place the compression member(s) in a maximally compressed configuration, i.e. with the highest possible compression ratio.

[0044] According to an optional characteristic of the invention, during the plating step the retaining system forms a stop against the movement of the second plate of the plate device and participates in pressing the first plate of the plate device, via the return effect of the compression member, against the portion of the sealing membrane.

[0045] During this plating step, the compression member tends to return to its rest configuration, and to this end it separates the plates from each other by pushing the first plate against the portion of sealing membrane and the second plate against the retaining system. This retaining system therefore provides a stop for the second plate of the plate device, which allows, when the compression member relaxes, pressure to be exerted against the portion of sealing membrane with a view to bonding it.

[0046] Other characteristics, details and advantages of the invention will emerge more clearly on reading the description which follows on the one hand, and examples of embodiment given for informational and non-limiting purposes with reference to the appended drawings on the other hand, in which:

[0047] [Fig-1] schematically illustrates, in perspective view, a wall of a tank of storage of a liquefied gas and a plating system participating in the bonding of a portion of the waterproofing membrane of the wall with its plate device and its retaining system, a plate of the plate device being partially represented to make visible compression members present within the plate device

[0048] [Fig.2] illustrates, schematically, according to a sectional view along a transverse and vertical plane, the tank wall and the plating system of [Fig.l], the plate device being in a plating configuration;

[0049] [Fig.3] schematically illustrates, in sectional view and in isolation, the plate device of [Fig.l] in a rest configuration in which its compression members are in a rest position;

[0050] [Fig.4] schematically illustrates, in sectional view, the plate device of [Fig.l] in its plating configuration as well as a vacuum system for the plating system;

[0051] [Fig.5] schematically illustrates, in sectional view and in isolation, the plate device of [Fig.l] in a compressed configuration in which its compression members have a maximum compression ratio;

[0052] [Fig.6] schematically illustrates, in a perspective view, the plate device of [Fig.l], one of its plates, namely the one opposite the portion of waterproofing membrane having been removed;

[0053] [Fig.7] schematically illustrates, in a perspective view similar to that of [Fig.6], a variant of the plate device of [Fig.l], the plate opposite the portion of waterproofing membrane having been removed.

[0054] The features, variants and different embodiments of the invention may be combined with each other, in various combinations, provided that they are not incompatible or mutually exclusive. In particular, variants of the invention may be imagined comprising only a selection of features described below in isolation from the other features described, if this selection of features is sufficient to confer a technical advantage and / or to differentiate the invention from the prior art.

[0055] In the figures, the elements common to several figures retain the same reference.

[0056] In the detailed description which follows, the terms “longitudinal”, “transverse” and “vertical” refer to the orientation of the plating system according to the invention. A longitudinal direction corresponds to a main extension direction of plates of the plate device of the plating system, this longitudinal direction being parallel to a longitudinal axis L of a reference frame L, V, T illustrated in the figures. A vertical direction corresponds to a direction in which the first plate, the receiving space and the second plate are superimposed, this vertical direction being parallel to a vertical axis V of the reference frame L, V, T and this vertical axis V being perpendicular to the longitudinal axis L. Finally, a transverse direction corresponds to a direction parallel to a transverse axis T of the reference frame L, V, T, this transverse axis T being perpendicular to the longitudinal axis L and to the vertical axis V.

[0057] Figures 1 and 2 thus illustrate, schematically, respectively a perspective view and a sectional view of a wall 1 of a storage tank. Such a storage tank is intended for the storage of a liquefied gas, such as for example liquefied natural gas, liquefied petroleum gas, ethane, methane, ammonia, nitrogen (dinitrogen), carbon dioxide or even hydrogen (dihydrogen). The storage tank is integrated into a floating structure or into a land-based installation for the storage, loading and unloading of the liquefied gas.

[0058] The wall 1 is formed of a plurality of panels arranged next to each other, with here a first panel 2 and a second panel 4. Each panel 2, 4 is composed of a plurality of layers promoting the sealing and insulation of the storage tank. Each panel 2, 4 thus comprises a primary layer 6 and a secondary layer 8, the primary layer 6 being intended to be in contact with the liquefied gas while the secondary layer 8 is secured to a support structure of the storage tank. Each of the primary layer 6 and the secondary layer 8 comprises a waterproofing membrane on the one hand and a thermally insulating layer on the other hand.

[0059] At a junction between two adjacent panels, here between the first panel 2 and the second panel 4, the waterproofing and thermal insulation of the wall 1 are managed by means of a portion of waterproofing membrane 10. Such a portion of waterproofing membrane 10 corresponds to an element of the wall 1 ensuring the waterproofing and thermal insulation between two adjacent panels 2, 4. This portion of waterproofing membrane 10 is a part of the secondary layer 8. It is for example a flexible secondary barrier. The portion of waterproofing membrane 10 covers a rigid secondary barrier 12 which lines the secondary layer 8. This rigid secondary barrier is in particular a triplex which comprises three successive layers, with here two layers of glass fibers framing an aluminum film.

[0060] As can be seen in Figures 1 and 2, the portion of sealing membrane 10 is arranged on the secondary layer 8 of the panels 2, 4, more precisely on their rigid secondary barrier 12.

[0061] The portion of sealing membrane 10 is more particularly bonded to the rigid secondary barrier 12 of the secondary layer 8 of the panels 2, 4 by means of a strip of glue 16. The bonding of the portion of sealing membrane 10 within the wall 1 involves a plating system 17, which will now be described in relation to FIGS. 1 to 7.

[0062] The plating system 17 comprises a plate device 18 on the one hand and a retaining system 40 on the other hand. The plate device 18 comprises two plates, here made of wood, including a first plate 20 and a second plate 22. These plates 20, 22 are of substantially rectangular shape and they extend mainly in a longitudinal-transverse plane, that is to say mainly in a longitudinal direction L and transverse T, perpendicular to a vertical direction V. The first plate 20 and the second plate 22 are superimposed on each other relative to this vertical direction V, so as to be substantially parallel. The first plate 20 is intended to be positioned opposite the portion of waterproofing membrane 10, with a view to bonding this portion of waterproofing membrane 10 within the wall 1.

[0063] The retaining system 40 makes it possible to hold the plate device 18 in position during bonding, and helps to press it against the portion of waterproofing membrane. Such a retaining system 40, shown in Figures 1 and 2, comprises in particular at least one retaining member 42, here retention bars or beams 42 intended to be in contact with the second plate 22 as well as at least one attachment means 44, here screws. The beams 42 are secured to the primary layers 6 of each of the panels 2, 4 by means of the attachment means 44.

[0064] The plate device 18 is intended to be positioned within a cavity of reception 23 formed in the wall 1 and delimited by the portion of waterproofing membrane 10, the primary layer 6 of the first panel 2 and the primary layer 6 of the second panel 4. The retaining system 40 extends from the primary layer 6 of the first panel 2 to the primary layer 6 of the second panel 4, covering the reception cavity 23 and the plate device 18 which is arranged within it.

[0065] The first plate 20 and the second plate 22 are arranged at a distance from each other, so as to delimit between them a receiving space 24. There is thus, in the vertical direction V, the first plate 20, the receiving space 24 and the second plate 22. This receiving space 24, which therefore corresponds to the space between the two plates 20, 22, comprises at least one housing 26 within which a compression member 28 is arranged. This housing 26 is in particular formed of two chambers 27 formed respectively in each of the plates 20, 22 facing each other. As shown in the figures, the receiving space 24 has two housings 26 each containing a compression member 28. It is understood that there is within the plate device 18 a first compression member 28A and a second compression member 28B.The housings 26 and the two compression members 28A, 28B extend mainly along the longitudinal direction L, and they are parallel to each other. The first compression member 28A extends along a first longitudinal edge of the plates 20, 22 while the second compression member 28B extends along a second longitudinal edge of these plates 20, 22. The two longitudinal edges are opposite each other in a transverse direction T.

[0066] In one embodiment, the plate device 18 comprises at least two compression members 28. Advantageously, the plate device comprises an even number of compression members 28. Unless otherwise stated, the characteristics which will be described subsequently in relation to one of the compression members 28A, 28B are intended to apply, mutatis mutandis, to the other compression member 28A, 28B.

[0067] The compression member 28 is for example a spring blade, as is particularly visible in Figures 6 and 7, the restoring force of which is exerted by undulations in the vertical direction V. The compression member 28 is arranged between the first plate 20 and the second plate 22, and extends in the longitudinal direction L from one end to the other of the plate device 18. The compression member 28 bears against each of the plates 20, 22. Depending on the spacing of the plates relative to each other, the spring blade is more or less compressed. And subsequently, the restoring force of the spring blade, which here corresponds to an extension force, tends to separate the plates from each other. The compression member 28 is thus compressible between a zero compression ratio which corresponds to its position of rest and a maximum compression rate. In order to prevent a translation of the compression member 28 out of the plate device 18, the latter comprises at least one blocking member 29 for a longitudinal movement of the compression member 28. Such a blocking member 29, visible in FIGS. 6 and 7, is arranged at one of the longitudinal ends of the compression member 28. In certain embodiments, the plate device 18 has a blocking member 29 at each of the ends of the compression member 28.

[0068] The receiving space 24 is closed laterally, that is to say between the first plate 20 and the second plate 22, by at least one sealing member 30. This sealing member 30, for example a rubber seal, is intended to prevent leaks within the plate device 18. The sealing member is secured to each of the first plate 20 and the second plate 22. The sealing member 30 is arranged on a periphery of this plate device 30, either at least partially within the receiving space 24 between the first plate 20 and the second plate 22, or outside the receiving space 24 around the first plate 20 and the second plate 22. The sealing member 30 can, depending on the case, compress or expand to accompany the movement of the plates 20, 22 during a change of configuration. of the plate device 18.

[0069] As is particularly visible in Figures 3 to 5, an orifice 32 is provided within the second plate 22. This orifice 32 opens into the receiving space 24. Advantageously, the orifice 32 is located at the center of the plurality of compression members 28. In another embodiment, the plate device 18 comprises a plurality of orifices 32. Advantageously, the plate device 18 comprises an orifice between each compression member 28. In another embodiment, the plate device 18 comprises an orifice 32 on one of the sides. Advantageously, the orifice 32 is located on the sealing member 30.

[0070] In certain embodiments, the orifice 32 opens into a channel 34 which communicates with the housing 26 within which the compression member 28 is arranged. Here, the channel 34 communicates both with the housing 26 which contains the first compression member 28A and the housing 26 which contains the second compression member 28B, the orifice 32 being arranged in the transverse direction T between the housing receiving the first compression member 28A and the housing receiving the second compression member 28B. In the embodiment shown in [Fig.7], the first plate 20 comprises a plurality of channels 34 connecting the housing 26 which contains the first compression member 28A and the housing 26 which contains the second compression member 28B.The portions of the first plate 20 arranged between these different channels 34 then constitute wedges for the compression members 28, so as to limit their movements other than compression within. of their respective housings 26. In [Fig.7], the first plate 20 comprises four channels 34, but one could, without departing from the scope of the invention, imagine embodiments in which the first plate 20 comprises a different number of such channels 34.

[0071] The orifice 32 is associated with a valve 36, which controls a fluid communication between the receiving space 24 on the one hand and a vacuum system 38 on the other hand. This vacuum system 38, which is illustrated in [Fig. 4], is for example a Venturi type system. The vacuum system 38 is configured to suck air present within the receiving space 24 in order to evacuate it from the plate device 18. In doing so, the first plate 20 and the second plate 22 move closer to each other and the compression member 28 compresses.

[0072] The compression ratio of the compression member(s) 28 defines a configuration of the plate device 18. Thus, the plate device 18 is in a rest configuration illustrated in [Fig. 3] when the compression member 28 has its rest position; it is in a compressed configuration illustrated in [Fig. 5] when the compression member 28 has the maximum compression ratio, and it is in a pressing configuration illustrated in FIGS. 2 and 4 when the compression member 28 has a compression ratio of between 0% and 100%, i.e. between the compression ratio of its rest position and the compression ratio of its compressed configuration. In other words, the pressing configuration of the plate device 18 is an intermediate configuration between the rest configuration and the compressed configuration.In this plating configuration of the plate device 18, the compression member 28 has a non-zero compression rate and less than the maximum compression rate.

[0073] The vacuum system 38 is configured to move the plate device 18 from its rest configuration to its compressed configuration, or from its plating configuration to its compressed configuration when it is necessary to uninstall the plating device while the retaining system is still fixed to the wall, by sucking the air present within the receiving space 24. In the rest configuration, the first plate 20 and the second plate 22 are at a maximum distance from each other, and conversely in the compressed configuration they are closest to each other. The suction of the air present within the receiving space 24 therefore contributes to bringing the two plates 20, 22 closer together and to compressing the compression member 28 by moving it from its rest position to its compressed position or its maximum compression rate.

[0074] When the vacuum system 38 is removed and the valve 36 is opened, air can enter the receiving space 24 and accompany the return effect of the compression member which tends to separate the plates from each other. The plating configuration of the plate device 18 in particular when the first plate 20 is in contact with the sealing wall and the second plate 22 is in contact with the beams 42 of the retaining system 40.

[0075] The plate device 18 is in its pressed configuration in Figures 2 and 4, in its rest configuration in [Fig. 3] and in its compressed configuration in [Fig. 5]. In the rest configuration, a distance DI between the plates, and more particularly between the external faces of each of the plates 20, 22, is maximum. When using the vacuum system 38, the air present in the receiving space 24 is sucked out and the distance between the plates is reduced to a minimum distance D2 or even zero, the plate device then taking its compressed configuration, the plates 20, 22 then being as close as possible to each other or even in contact with each other. When the plate device 18 is in its pressed configuration, the distance between the plates is an intermediate distance D3 which is between the maximum distance DI and the minimum distance D2.The distances D1, D2, D3 are for example measured between a face of the first plate 20 opposite the second plate 22 and a face of the second plate 22 opposite the first plate 20.

[0076] The receiving cavity 23 is delimited by a height of the primary mass of the insulation, measured along the vertical direction V, between 70 mm and 110 mm, more advantageously between 80 mm and 100 mm, a width, measured along the transverse direction T, between 340 mm and 600 mm, and a length, measured along the longitudinal direction L, between 500 mm and 3100 mm.

[0077] Advantageously, the height of the receiving cavity 23 is 100 mm. The plate device 18 has an overall height of approximately 110 mm in its rest configuration, a height substantially equal to that of the receiving cavity 23, i.e. 100 mm, in its pressed configuration, and in its compressed configuration, i.e. after application of the vacuum, the plate device 18 has a height of less than 100 mm, up to 80 mm.

[0078] A method of plating the portion of sealing membrane 10 within the wall 1 of the storage tank will now be described. This plating method begins with a step during which the adhesive strip 16 is deposited on the rigid secondary barrier 12 which covers the secondary layer 8 of the two adjacent panels 2, 4. The portion of sealing membrane 10 is then positioned between the primary layers 6 of these two panels 2, 4 on the adhesive strip 16. In order to maintain the portion of sealing membrane 10 in position in contact with the adhesive strip 16, it is necessary to apply pressure to this portion of sealing membrane 10 for a duration corresponding to the time required for the adhesive strip 16 to crosslink, for example a duration of the order of a few hours.

[0079] For this purpose, an operator responsible for laying the portion of waterproofing membrane 10 uses the plating device 17. The plate device 18 is initially in its rest configuration, visible in [Fig. 3], in which the compression member 18 is in its rest position. The operator uses the vacuum system 38 which he connects to the valve 36 connected to the orifice 32. The start-up of the vacuum system 38, during a vacuum step, causes the air present in the receiving space 24 to be sucked out, which creates a vacuum in the plate device 18 and tends to bring the plates closer to each other. As the two plates 20, 22 come together and the compression member 28 is compressed, the plate device 18 passes from its rest configuration to its compressed configuration illustrated in [Fig.5].In this compressed configuration, in which the compression member 28 has its maximum compression ratio, the plate device 18 is, during a positioning step, placed in the receiving cavity 23 between the primary layers 6 of the two panels 2, 4. During a positioning step, the retaining system 40 is installed on the wall 1 covering the receiving cavity 23, the retaining system 40 extending from the primary layer 6 of the first panel 2 to the primary layer 6 of the second panel 4. The retaining system 40 is fixed to the wall 1 by means of its attachment means 44. A thickness of the plate device 18 measured in the vertical direction V is then less than a dimension of this receiving cavity 23 also measured in the vertical direction V between the portion of waterproofing membrane 10 and the beams 42 of the retaining system 40.In certain alternative embodiments, the step of placing the retaining system 40 occurs prior to the step of positioning the plate device 18 within the receiving cavity 23, and where appropriate prior to the step of placing the plating device under vacuum.

[0080] Once the retaining system 40 is installed, the vacuum system 38 is removed and the valve 36 is opened. Due to the return effect of the compression member, the latter deploys and the plates 20, 22 then move apart from each other until the second plate 22 is in contact with the beams 42 of the retaining system 40 and until the first plate 20 is in contact with the portion of sealing membrane 10. In other words, due to a possible return of air into the housing 26, the compression member 28 decompresses so that the plate device 18 passes from its compressed position to its pressed position. The plating configuration is achieved when the second plate 22 is pressed against the beams 42 of the retaining system 40, while the first plate 20 exerts pressure against the portion of waterproofing membrane 10 which in turn presses on the adhesive strip 16.

[0081] In order to facilitate the bonding of the portion of waterproofing membrane 10, a heating of the glue strip 16 is operated by a heating member such as a heating resistor of the plating system 17.

[0082] Once the bonding time has elapsed, firstly the plate device 18 is removed from the wall 1 and then the retaining system 40 is removed in turn. Such removal of the plate device 18 involves the vacuum system 38, which sucks the air present in the receiving space 24 to make it pass into its compressed configuration and thus extract it more easily from the receiving cavity 23 of the wall 1, the retaining system 40 then still being in place.

[0083] The plating method according to the invention thus makes it possible to apply pressure to the portion of waterproofing membrane 10 for the time necessary for it to be bonded against the panels 2, 4 of the wall 1.

[0084] The present invention thus proposes a tool making it possible to ensure continuity of sealing between two panels of a storage tank wall, in a simple and secure manner by applying pressure to a portion of the sealing membrane 10 to be installed in contact with a strip of glue placed on a portion of the wall panels already in place.

[0085] The present invention cannot, however, be limited to the means and configurations described and illustrated here and it also extends to any equivalent means and configuration as well as to any technically operative combination of such means.

Claims

Claims

1. System for plating (17) a portion of sealing membrane (10) of a wall (1) of a liquefied gas storage tank, comprising a plate device (18) and a retaining system (40) capable of being fixed on the wall (1) covering a receiving cavity (23) of the wall (1) capable of receiving the plate device (18), the plate device (18) comprising: - a first plate (20) intended to be positioned opposite the portion of sealing membrane (10); - a second plate (22) arranged substantially parallel and at a distance from the first plate (20) relative to a vertical axis (V); - a receiving space (24) delimited between the first plate (20) and the second plate (22) which extends mainly along a plane perpendicular to the vertical axis (V); - at least one compression member (28, 28A, 28B) arranged in the receiving space (24);the plate device (18) being configured to have a compressed configuration in which the compression member (28, 28A, 28B) undergoes a compression force along the vertical axis (V) making it possible to arrange the plate device (18) in the receiving cavity (23), and a pressing configuration in which the compression member (28, 28A, 28B) undergoes an extension force along the vertical axis (V) making it possible to press the second plate (22) against the retaining system (40) and the first plate (20) against the portion of sealing membrane (10).;

2. Plating system (17) according to claim 1, wherein the plate device (18) comprises at least one sealing member (30) closing the receiving space (24).

3. A plating system (17) according to claim 1 or 2, comprising a vacuum system (38) configured to place the plate device (18) in its compressed configuration.

4. Plating system (17) according to claim 3, wherein the second plate (22) comprises at least one orifice (32) for receiving the vacuum system (38).

5. Plating system (17) according to any one of claims 1 to 4, in which the receiving space (24) comprises at least one housing (26) within which the compression member (28, 28A, 28B).

6. Plating system (17) according to any one of claims 1 to 5, wherein the retaining system (40) comprises at least one retaining member (42) intended to be fixed to the wall (1) of the storage tank.

7. A plating system (17) according to any one of claims 1 to 6, wherein the plate device (18) comprises at least a first compression member (28A) and a second compression member (28B) extending parallel along a longitudinal axis (L) perpendicular to the vertical axis (V).

8. A plating system (17) according to claim 7 in combination with claim 4, wherein the orifice (32) is disposed between the first compression member (28A) and the second compression member (28B).

9. Plating system (17) according to any one of claims 1 to 8, wherein the plate device (18) comprises at least one blocking member (29) of a longitudinal movement of the compression member (28, 28A, 28B).

10. A plating system (17) according to any one of claims 1 to 9, wherein the compression member (28, 28A, 28B) is a spring blade extending from one longitudinal end to the other of the plate device (18).

11. Use of a plating system (17) according to any one of claims 1 to 10, in which the plating system (17) is used to hold the portion of sealing membrane (10) in position while it is bonded to the wall (1) of the liquefied gas storage tank.

12. Method for plating a portion of sealing membrane (10) of a wall (1) of a liquefied gas storage tank using a plating system (17) according to any one of claims 1 to 10, comprising at least one compression step during which the plate device (18) passes into the compressed configuration, a positioning step during which the plate device (18) is placed so that the first plate (20) is in contact with the portion of sealing membrane (10), a positioning step during which the retaining system (40) is positioned against the wall (1) and a plating step in which the plate device (18) passes from its compressed configuration to its plating configuration.

13. A plating method according to claim 12 in combination with claim 3, wherein during the compression step air present in the receiving space (24) is sucked out by the vacuum system (38).

14. Plating method according to claim 12 or 13, wherein during the plating step the retaining system (40) forms a stop to the movement of the second plate (22) of the plate device (18) and participates in plating the first plate (20) of the plate device (18), via the return effect of the compression member (28, 28A, 28B), against the portion of sealing membrane (10).

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