Waterproof and thermally insulating tank including bridging plates

Abstract

The invention relates to a sealed and thermally insulating tank (1) for storing a fluid, the tank (1) comprising a tank wall comprising a sealing membrane (14) and a thermally insulating barrier (12) comprising at least two insulating panels (13) and arranged between the sealing membrane (14) and the load-bearing wall, the two insulating panels (13) being juxtaposed, delimiting an inter-panel space (25) between them, the thermally insulating barrier (12) comprising at least one insulating seal (26) housed in the inter-panel space (25) and bridging plates (30) arranged above the at least one insulating seal (26) so as to extend astride the two insulating panels (13), each bridging plate (30) being provided with two main faces (31A, 31B) parallel to the internal face of the thermally insulating barrier (12) and connected by two longitudinal end surfaces (33A, 33B;33A', 33B') located at the longitudinal ends of the bridging plate (30). According to the invention, the longitudinal end surface (33A; 33A') of a first of the bridging plates (30) and a longitudinal end surface (33B; 33B') of a second of the bridging plates (30) arranged opposite each other have a nesting system (40) which extends astride the two insulating panels (13) in the transverse direction (A11) of the inter-panel space (25) to extend a flow path between the first and second bridging plates (30). Figure for abstract: Fig. 2;

Description

Title of the invention: Sealed and thermally insulating tank comprising bridging plates Technical field

[0001] The invention relates to the field of storage and / or transport of a fluid.

[0002] In particular, the invention relates to the field of sealed and thermally insulating tanks for the storage and / or transport of a cryogenic fluid, for example liquefied gas at low temperature, such as tanks for the transport of Liquefied Natural Gas (LNG) at approximately -162°C at atmospheric pressure, liquid Hydrogen (LH2) at -253°C at atmospheric pressure, ammonia (NH3) at -30°C at atmospheric pressure or Liquefied Petroleum Gas (also called LPG) having, for example, a temperature of between -50°C and 0°C. These tanks can be installed on land or on a floating structure. In the case of a floating structure, the tank can be intended for the transport of liquefied gas or for receiving liquefied gas used as fuel for the propulsion of the floating structure. Technological background

[0003] In document FR3082274, it is known to use a sealed and thermally insulating tank for the transport and / or storage of a fluid, comprising insulating panels covered by a corrugated sealing membrane. The sealing membrane has an inner face, intended to be in contact with the fluid contained in the tank, and an outer face, facing the thermally insulating barrier. The sealing membrane is made up of a plurality of metal plates, made of stainless steel, having series of perpendicular corrugations allowing the absorption of forces. The corrugated plates are welded to each other, along their edges, and are anchored to the insulating panels, by welding the edges of the plates to strips, also made of stainless steel, riveted to said insulating panels.

[0004] The insulating panels each have an internal face facing the inside of the tank and covered by the waterproofing membrane. They are juxtaposed with each other. The insulating panels include edges having counterbores for receiving bridging plates, for example made of plywood. The bridging plates are fixed to the cover plates of two adjacent insulating panels to prevent them from separating at their junction and thus improve the uniformity of the support surface where the waterproofing membrane rests.

[0005] The bridging plates used are juxtaposed next to each other along the longitudinal direction of the inter-panel space. Each bridging plate is provided with two main faces parallel to the internal face of the thermally insulating barrier and connected by two transverse end surfaces and by two longitudinal end surfaces, the longitudinal end surfaces being located at the longitudinal ends of the bridging plate. These longitudinal end surfaces are straight. They are flat and extend perpendicular to the parallel main faces of the bridging plate.

[0006] In the event of a leak in the sealing membrane, fluid may possibly infiltrate between the longitudinal end surfaces of two adjacent bridging plates and between the two insulating panels. However, such infiltration of fluid into the thermally insulating barrier will be stopped by a secondary sealing membrane. Summary

[0007] One idea underlying the invention is to provide a tank in which the risk of fluid infiltration through the wall of the tank is reduced. Another idea underlying the invention is to provide a sealed and thermally insulating tank in which part of the tank, or even the entire tank, employs a single sealed barrier. Another idea underlying the invention is to provide a sealed and thermally insulating tank capable of serving as a ship's fuel tank for a long time, which means supporting varying filling levels.

[0008] The invention provides a sealed and thermally insulating tank for storing a fluid, the tank comprising a tank wall fixed to a load-bearing wall, the tank wall comprising a sealing membrane and a thermally insulating barrier arranged between the sealing membrane and the load-bearing wall.

[0009] - the sealing membrane having an inner face, intended to be in contact with the fluid contained in the tank, and an external face, facing the thermally insulating barrier,

[0010] - the thermally insulating barrier comprising at least two insulating panels each having an internal face facing the inside of the tank and covered by the waterproofing membrane, the two insulating panels being juxtaposed, delimiting an inter-panel space between them, said inter-panel space extending in a longitudinal direction,

[0011] the thermally insulating barrier comprising at least one insulating joint housed in the inter-panel space and bridging plates arranged above the at least one insulating joint so as to extend astride the two insulating panels in a transverse direction of the inter-panel space, each bridging plate having an elongated shape in the longitudinal direction of the inter-panel space, each bridging plate being provided with two main faces parallel to the internal face of the thermally insulating barrier, connected by two transverse end surfaces and by two longitudinal end surfaces, the longitudinal end surfaces being located at the longitudinal ends of the bridging plate,

[0012] wherein a longitudinal end surface of a first of the bridging plates and a longitudinal end surface of a second of the bridging plates arranged opposite the longitudinal end surface of the first bridging plate have an interlocking system which extends astride the two insulating panels in the transverse direction of the inter-panel space to lengthen a flow path between the first and second bridging plates.

[0013] Thus, remarkably, the shape of the bridging plates ensures partial overlapping of the bridging plates juxtaposed successively along the longitudinal direction of the inter-panel space.In the event that fluid splashes from the tank reach the junction between the bridging plates, the risk of these fluid splashes passing through the bridging plates and reaching the insulating joint is reduced. This is because the bridging plates are nested within each other so that the flow path that the fluid splashes must follow to pass through the bridging plates is elongated. Thus, even in the absence of a secondary watertight barrier, the ship's hull is not at risk of being hit by fluid splashes.

[0014] According to embodiments, such a tank may comprise one or more of the following characteristics.

[0015] According to one embodiment, the two longitudinal end surfaces of each bridging plate have shapes complementary to each other capable of forming said nesting system. Thus, several bridging plates produced according to this arrangement can be nested successively two by two by their adjacent ends. The two longitudinal end faces of the same bridging plate cannot of course be nested with each other since they are not adjacent to each other.

[0016] According to one embodiment, said nesting system has an overlap clearance greater than 10 millimeters (mm), preferably between 10 and 30 millimeters, in the longitudinal direction of the inter-panel space. Thus, the nesting system allows a tolerance in the positioning of the bridging plates while maintaining a certain efficiency. This value of the overlap clearance allows effective protection against fluid projections.

[0017] According to one embodiment, at least one of the longitudinal end surfaces of each bridging plate has at least one adjustment surface parallel to the main faces of the bridging plate. Thus, when two bridging plates are nested inside each other, they can slide slightly relative to each other against this adjustment surface while remaining joined. This ensures a effective protection against fluid splashes while allowing slight deformation of the thermally insulating barrier.

[0018] According to one embodiment, the at least one adjustment surface is connected to at least one of the two main faces of the bridging plate by a connecting surface perpendicular to the main face.

[0019] According to one embodiment, the nesting system comprises a rib formed in the first bridging plate and projecting in the longitudinal direction towards the second bridging plate, and a housing formed in the second bridging plate and receiving said rib. This arrangement allows simple and effective nesting of two bridging plates.

[0020] According to one embodiment, the rib of the first bridging plate is delimited partly by one of the two main faces of the first bridging plate and partly by a recess in the longitudinal end surface of the first bridging plate, and the housing of the second bridging plate opens onto a corresponding main face of the second bridging plate. This structure allows particularly simple mounting of the bridging plates.

[0021] According to one embodiment, the rib of the first bridging plate is delimited by two recesses of the longitudinal end surface of the first bridging plate and the housing of the second bridging plate forms a groove in the longitudinal end surface of the second bridging plate. This structure makes it possible to fix two bridging plates on top of each other while allowing a relative translational movement of one of the two plates relative to the other in the longitudinal direction of the inter-panel space.

[0022] According to one embodiment, the waterproofing membrane comprises at least one projecting corrugation on the side of the inner face of the waterproofing membrane, said corrugation extending in a direction orthogonal to the longitudinal direction of the inter-panel space, at right angles to the nesting system.

[0023] According to one embodiment, the tank wall comprises a single barrier wall portion, the single barrier wall portion comprising said insulating panel juxtaposed with a plurality of identical insulating panels forming a thermally insulating barrier surmounted by the sealing membrane, said thermally insulating barrier being fixed to the load-bearing wall, without any other sealing membrane interposed between the thermally insulating barrier and the load-bearing wall.

[0024] The tank wall then comprises a simplified wall part which is less expensive to produce.

[0025] According to one embodiment, said single barrier wall portion is arranged in an upper portion of the tank, located above a substantially horizontal median plane of the tank. The upper portion of the tank being less often in contact with the fluid contained in the tank, a simplified wall section can be installed there. The risk of the load-bearing wall being exposed to the fluid contained in the tank is lower in the upper part of the tank.

[0026] According to one embodiment, said single barrier wall portion forms the ceiling of the tank.

[0027] According to one embodiment, the tank wall further comprises a double barrier wall portion comprising a primary sealing membrane intended to be in contact with the fluid contained in the tank, a secondary sealing membrane arranged between the primary sealing membrane and the load-bearing wall, a primary thermally insulating barrier arranged between the primary sealing membrane and the secondary sealing membrane and a secondary thermally insulating barrier arranged between the secondary sealing membrane and the load-bearing wall,

[0028] the thickness of each insulating panel forming the single barrier wall portion is equal to the cumulative thickness of the primary and secondary thermally insulating barriers and the secondary sealing membrane of the double barrier wall portion such that the inner face of the insulating panels of the single barrier wall portion extends in the extension of an inner face of insulating panels forming the primary thermally insulating barrier of the double barrier wall portion, and

[0029] the waterproofing membrane of the single barrier wall portion and the primary waterproofing membrane of the double barrier wall portion extend in line with each other.

[0030] It is thus possible to obtain a tank wall whose internal face is continuous, having an economical single-barrier wall part in the upper part least in contact with the fluid and a double-barrier wall part in a lower part of the tank most in contact with the fluid.

[0031] According to one embodiment: - each insulating panel has four peripheral faces extending from said internal face,

[0032] - the sealing membrane comprises first corrugations extending along a first main direction parallel to the longitudinal direction of the interpanel space,

[0033] - the sealing membrane further comprising second corrugations pa lines extending in a second main direction orthogonal to the longitudinal direction of the inter-panel space,

[0034] the insulating panel comprising:

[0035] - first relaxation slots, extending in a thickness of the panel insulating, from the internal face of the insulating panel, opposite the first undulations of the waterproofing membrane, according to the first main direction and comprising two first extreme relaxation slots, each first extreme relaxation slot corresponding to the first relaxation slot closest to one of the two first peripheral faces of the insulating panel and

[0036] - second relaxation slots, extending into the thickness of the insulating panel, from the internal face of the insulating panel, opposite the second corrugations of the waterproofing membrane, in the second main direction, and comprising two second extreme relaxation slots, each second extreme relaxation slot corresponding to the second relaxation slot closest to one of the two second peripheral faces of the insulating panel,

[0037] each first relaxation slot intersecting at least one or each of the second relaxation slots and extending between two ends each located between one of the two second extreme relaxation slots and the second peripheral face of the adjacent insulating panel, at a distance from the second peripheral face,

[0038] and each second relaxation slot intersecting at least one or each of the first relaxation slots and extending between two ends each located between one of the two first extreme relaxation slots and the first peripheral face of the adjacent insulating panel, at a distance from the first peripheral face.

[0039] The use of non-opening slots on the peripheral faces of the insulating panels reinforces the sealing of the tank wall.

[0040] According to one embodiment, the first corrugations are mutually spaced by a first corrugation pitch and a distance between the first extreme relaxation slots and the first peripheral faces is less than the first corrugation pitch, preferably equal to half of the first corrugation pitch.

[0041] According to one embodiment, the second corrugations are mutually spaced by a second corrugation pitch and a distance between the second extreme relaxation slots and the second peripheral faces is less than the second corrugation pitch, preferably equal to half of the second corrugation pitch.

[0042] Thanks to these characteristics, it is possible to obtain a positioning of the corrugations which promotes the uniformity of the stresses applied to the different corrugations. The first corrugation pitch and the second corrugation pitch may be equal or different.

[0043] According to one embodiment, the distance between the end of each of the first and second relaxation slots and the first or second peripheral face of the adjacent insulating panel is between 5 and 50 millimeters.

[0044] According to one embodiment, each relaxation slot is obtained by cutting with a circular saw.

[0045] According to one embodiment, each relaxation slot extends in a plane perpendicular to the internal face of the insulating panel.

[0046] According to one embodiment, the insulating panel comprises a layer of polymer foam sandwiched between a rigid upper plate and a rigid lower plate.

[0047] According to one embodiment, each relaxation slot extends through the rigid upper plate and over a portion of the thickness of the polymer foam layer without reaching the rigid lower plate.

[0048] The invention also relates to a ship comprising a hull, a propulsion system and a sealed and thermally insulating tank as described above, for storing a liquefied combustible gas intended to supply the combustible gas to the propulsion system.

[0049] The invention also provides a transfer system for a liquefied fuel gas, the system comprising the aforementioned vessel, insulated pipes arranged to connect the vessel's tank to a floating or land-based storage facility and a pump for driving a flow of liquefied fuel gas through the insulated pipes from the floating or land-based storage facility to the vessel's tank.

[0050] Finally, the invention also provides a method for loading such a ship, in which a liquefied combustible gas is conveyed through insulated pipes from a floating or land-based storage facility to the ship's tank. Brief description of the figures

[0051] The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes, with reference to the appended drawings.

[0052] [Fig.l] schematically represents a partial view of a tank according to the invention in its supporting structure;

[0053] [Fig.2] is a schematic representation of a part of a wall of the tank of the [Fig.l];

[0054] [Fig.3] is a schematic representation in section along plane III-III of [Fig.2] of a first embodiment of the wall part of [Fig.2];

[0055] [Fig.4] is an enlarged schematic representation of zone IV of [Fig.3];

[0056] [Fig.5] is a representation similar to the representation of [Fig.4] of a second embodiment of the wall part of [Fig.2];

[0057] [Fig.6] is a schematic representation in section along the VLVI plane of the wall of [Fig.2],

[0058] [Fig.7] is a schematic representation of an example of the embodiment of a panel insulation of the wall of [Fig.2];

[0059] [Fig.8] is a schematic representation in section along plane VIII-VIII of the [Fig.7] of the insulating panel of [Fig.7];

[0060] [Fig.9] is a schematic representation of another example of embodiment of an insulating panel of the wall of [Fig.2];

[0061] [Fig. 10] is a schematic cutaway representation of a LNG carrier tank and a loading / unloading terminal for this tank. Description of the embodiments

[0062] In [Fig. 1], a particular example of an embodiment of a sealed and thermally insulating tank 1 for storing a fluid, anchored to a supporting structure IA, is shown schematically.

[0063] The fluid is in particular a cryogenic fluid transported at low temperatures. It may be a liquefied gas, in particular a liquefied natural gas (LNG), that is to say a gas mixture comprising mainly methane as well as one or more other hydrocarbons, such as ethane, propane, n-butane, i-butane, n-pentane, i-pentane, neopentane, and nitrogen in small proportion.

[0064] The liquefied gas can also be ethane or liquefied petroleum gas (LPG), i.e. a mixture of hydrocarbons from oil refining, essentially comprising propane and butane.

[0065] Liquefied natural gas is stored at a temperature of approximately -162°C at atmospheric pressure.

[0066] Alternatively, the liquefied gas may be liquid hydrogen (LH2) stored at -253°C at atmospheric pressure, or ammonia (NH3) stored at -30°C at atmospheric pressure.

[0067] In relation to [Fig.l], the supporting structure IA is described against which the sealed and thermally insulating tank 1 for storing a fluid is intended to be fixed. The supporting structure IA is, for example, formed by the double hull of a ship. The double hull comprises an outer hull 19 and an inner hull 18 arranged inside the outer hull 19. The supporting structure IA has a generally polyhedral shape. It has two front and rear supporting walls 2, here octagonal in shape. The front supporting wall is not shown in [Fig.l] in order to allow the interior of the tank 1 to be viewed. The front and rear walls 2 are, for example, cofferdam walls of the ship which extend transversely to the longitudinal direction of the ship. The load-bearing structure IA also comprises an upper load-bearing wall 3, a lower load-bearing wall 4 and side load-bearing walls 5, 6, 7, 8, 9, 10.

[0068] Alternatively, the shape of the tank may be different, for example parallelepiped. The supporting structure may be entirely or partially separate from the hull of the ship, as is for example described in document FR3122400.

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[0079] The tank 1 comprises a plurality of tank walls which are each anchored against one of the load-bearing walls 2, 3, 4, 5, 6, 7, 8, 9, 10 of the load-bearing structure IA. The walls of the tank 1 define an internal space intended to contain the fluid, for example liquefied gas. The tank 1 thus comprises at least one tank wall fixed to one of the load-bearing walls 2-10 described above. The tank wall comprises a sealing membrane 14 and a thermally insulating barrier 12 arranged between the sealing membrane 14 and the load-bearing wall of the load-bearing structure 1A as shown in [Fig.2], More precisely, the tank wall presents successively, from the outside to the inside, according to the direction of wall thickness: - the thermally insulating barrier 12 comprising insulating panels 13; - the sealing membrane 14 anchored to the insulating panels 13 of the thermally insulating barrier 12 ([Fig.2]). The thermally insulating barrier 12 comprises at least two insulating panels 13. Each insulating panel 13 has a generally elongated parallelepiped shape, with: - an internal face 22A facing the inside of the tank and covered by the sealing membrane 14, - an external face 23A opposite the internal face 22A, and - and four peripheral faces 21A, 21B extending from said face internal 22A. The four peripheral faces 21A, 21B connect the internal face 22A to the external face 23A. The insulating panels 13 of the thermally insulating barrier 12 each comprise, for example, a layer of insulating polymer foam 21, for example polyurethane, sandwiched between a rigid cover plate 22 and a base plate 23, for example plywood ([Fig.6]). The polymer foam can advantageously be reinforced with glass fibers helping to reduce its thermal contraction. The inner face 22A of the insulating panel 13 belongs to the cover plate 22 while the outer face 23A of the insulating panel 13 belongs to the bottom plate 23. Two insulating panels 13 are juxtaposed, delimiting between them an inter-panel space 25. The inter-panel space 25 is delimited by one of the peripheral faces 21A, 21B of a first of the insulating panels 13 and the adjacent peripheral face 21A, 21B of the neighboring insulating panel 13 (figures 2, 6). Said inter-panel space 25 extends in a longitudinal direction A1 which is parallel to one of the peripheral faces 21A, 21B of the insulating panel 13.

[0080] In the attached figures 3 to 6 and in the remainder of the description, the insulating panels 13 have an elongated shape along a longitudinal axis. The insulating panel 13 comprises first longitudinal peripheral faces 21A corresponding here to the longest sides of the parallelepiped formed by the insulating panel 13 and second transverse peripheral faces 21B corresponding to the smallest side of the parallelepiped formed by the insulating panel 13.

[0081] In the following, the inter-panel space 25 formed between the first longitudinal peripheral faces 21A of the insulating panels 13 has been described and shown. The longitudinal direction A1 of the inter-panel space 25 is here parallel to the first longitudinal peripheral faces 21A of the insulating panel 13 and to the longitudinal axis of the insulating panel 13.

[0082] The structure of the insulating panel 13 is identical at the level of the second transverse peripheral faces 21B of the insulating panels 13 which also delimit inter-panel spaces 25 ([Fig.2]).

[0083] The thermally insulating barrier 12 further comprises at least one insulating seal 26 housed in the inter-panel space 25 and bridging plates 30 arranged above the at least one insulating seal 26 so as to extend astride the two insulating panels 13 in a transverse direction A11 of the inter-panel space 23 (Figures 2 to 6). The transverse direction A11 of the inter-panel space 25 is perpendicular to the longitudinal direction A1 of this inter-panel space 25.

[0084] The insulating joint 26 may for example be made of glass wool, rock wool or flexible open-cell synthetic foam. It may be wrapped in kraft paper. The insulating joint 26 is preferably made of a porous material so as to provide gas circulation spaces in the inter-panel spaces 25 between the insulating panels 13. Such gas circulation spaces are advantageously used to allow circulation of inert gas, such as nitrogen, within the thermally insulating barrier 12 so as to maintain it under an inert atmosphere. Thus, in the event of a leak, the liquefied gas converted to the gaseous state will not be able to form an explosive environment with the oxygen in the air. Furthermore, this makes it possible to place the thermally insulating barrier 12 under vacuum in order to increase its insulating power. This gas circulation is also important to facilitate the detection of possible liquefied gas leaks.The inter-panel spaces 25 have, for example, a width of the order of 30 mm.

[0085] Each bridging plate 30 has an elongated shape along the longitudinal direction A1 of the inter-panel space 25 and is provided with two main faces 31A, 31B parallel to the internal faces 22A of adjacent insulating panels 13 and connected by two transverse end surfaces 32 ([Fig.6]) and by a first and a second opposite longitudinal end surface 33A; 33A', 33B; 33B'.

[0086] The longitudinal end surfaces 33A; 33A', 33B; 33B' are located at the longitudinal ends of the bridging plate 30 (Figures 2 to 5).

[0087] The internal face 22A of the cover plate 22 of each insulating panel 13 comprises, along a peripheral edge running along the peripheral faces 21A, 21B of the insulating panel 13, a recess 28 which accommodates the bridging plates 30 (figures 6 and 7).

[0088] An external main face 31B of the bridging plates 30, facing the insulating polymer foam layer 21, is fixed against the bottom of the recesses 28. The depth of the recesses 28 is substantially equal to the thickness of the bridging plates 30 such that an internal main face 31A of the bridging plates 30, facing the sealing membrane 14, reaches substantially the level of the internal face 22A of an adjacent cover plate 22. Thus, the bridging plates 30 are able to ensure continuity in the support of the sealing membrane 14.

[0089] The recesses 28 on either side of the inter-panel space 25 form a housing for the bridging plate 30. The housing has a transverse dimension slightly greater than the transverse dimension of the bridging plate 30 so as to overcome assembly and / or manufacturing tolerances when inserting the bridging plate 30 into the housing.

[0090] The bridging plates 30 can be fixed against the cover plates 22 of the insulating panels 13 by any suitable means, for example by staples.

[0091] The first longitudinal end surface 33A; 33A' of a first of the bridging plates 30 and the second longitudinal end surface 33B; 33B' of a second of the bridging plates 30 arranged opposite the first longitudinal end surface 33A; 33A' of the first bridging plate 30 have an interlocking system 40 (Figures 3 to 5) which extends astride two adjacent insulating panels 13 in the transverse direction A11 of the inter-panel space 25 to lengthen a flow path for any fluid projections between the first and second bridging plates 30.

[0092] Preferably, the thermally insulating barrier 12 comprises a plurality of bridging plates 30 aligned above the inter-panel space 25. All the bridging plates 30 have an identical shape. There is therefore no difference between the first and second bridging plates 30. The first bridging plate on the left in Figures 4 and 5 and the second bridging plate on the right will be arbitrarily described below.

[0093] In practice, the nesting system 40 is configured so that the main faces 31 of the bridging plates 30 extend in line with each other.

[0094] The nesting system 40 comprises the longitudinal end surfaces 33A, 33B arranged opposite two adjacent bridging plates 30. It ensures partial covering of one of the two bridging plates 30 by the other. In practice, the first longitudinal end surface 33A; 33A' of one of the two adjacent bridging plates 30 partially covers the second longitudinal end surface 33B; 33B' of the other bridging plate 30, all along the second longitudinal end surface 33B; 33B' (figures 4 and 5).

[0095] Conversely, it may be provided that the second longitudinal end surface of one of the two adjacent bridging plates partially covers the first longitudinal end surface of the other bridging plate, all along the first longitudinal end surface.

[0096] Thus, in the event of fluid infiltration through the sealing membrane 14, the risk of the fluid passing through the bridging plates 30 is reduced because the flow path accessible to the fluid between the two bridging plates 30 is elongated compared to the prior art. In the prior art, the longitudinal end surfaces of the bridging plate are planar and extend parallel to each other, perpendicular to the main faces of the bridging plate.

[0097] Preferably, said nesting system 40 has an overlap clearance greater than 10 millimeters (mm) in the longitudinal direction A1 of the interpanel space 25. This overlap clearance is for example between 10 and 30 mm.

[0098] In other words, the first longitudinal end surface 33A; 33A' of one of the adjacent first and second bridging plates 30 partially overlaps the second longitudinal end surface 33B; 33B' of the other of the first and second bridging plates 30 over a distance greater than or equal to 10 millimeters, preferably between 10 and 30 millimeters. This distance is measured along the longitudinal direction A1 of the inter-panel space.

[0099] Thus, the nesting system 40 allows a tolerance in the positioning of the bridging plates 30 while maintaining a certain efficiency.

[0100] The two longitudinal end surfaces 33A, 33B; 33A', 33B' of each bridging plate 30 have shapes complementary to one another capable of forming said nesting system 40.

[0101] In other words, the first longitudinal end surface 33A; 33A' of one of the first and second bridging plates 30 and the second longitudinal end surface 33B; 33B' of the other of the first and second bridging plates 30 have shapes adapted to fit into one another, for example complementary shapes.

[0102] These may be any type of shapes suitable for nesting within each other, for example sawtooth, curved or stepped. Each longitudinal end surface 33A, 33B; 33A', 33B' preferably has a uniform shape along the transverse direction Ail to the inter-panel space 25.

[0103] The nesting can also be done by adding a complementary part interposed between two adjacent bridging plates. For example, it is possible to envisage that the two longitudinal ends of each bridging plate are identical and each have a longitudinal end surface delimiting a groove-shaped housing, such as the housing 42' shown in [Fig. 5]. The two housings open opposite each other when the two adjacent bridging plates are placed end to end. The complementary part can then have the shape of a plate, being housed entirely in the two housings of the two adjacent bridging plates.

[0104] Preferably, at least one of the longitudinal end surfaces 33A; 33A', 33B; 33B' of each bridging plate 30 has at least one adjustment surface 34, 34' parallel to the main faces 31 of the bridging plate 30. The at least one adjustment surface 34, 34' is for example connected to at least one of the two main faces 31 of the bridging plate 30 by a connecting surface perpendicular to the main face 31.

[0105] Alternatively, the connecting surface could be inclined relative to the main face by an angle of value other than 90°, for example an angle between 45 and 135°.

[0106] The bridging plate having a connecting surface perpendicular to the main face has the advantage of being simple to manufacture.

[0107] The presence of this adjustment surface 34, 34' allows a range of relative positioning between the two adjacent bridging plates 30 along the longitudinal direction A1 of the inter-panel space 25 while maintaining contact between the first longitudinal end surface 33A; 33A' of one of the two bridging plates 30 and the second longitudinal end surface of the other bridging plate 30. The two adjacent bridging plates 30 remain contiguous over the entire range of relative positioning. The mounting of the bridging plates 30 is thus made easier.

[0108] Preferably, each longitudinal end surface 33A, 33B; 33A', 33B' comprises such an adjustment surface 34, 34'. The adjustment surface 34, 34' of the first longitudinal end surface of a bridging plate 30 and the adjustment surface 34, 34' of the second longitudinal end surface of the adjacent bridging plate 30 are pressed against each other when the bridging plates 30 are nested within each other.

[0109] Thus, in the event of fluid infiltration through the sealing membrane 14, the risk of the fluid passing through the bridging plates 30 is reduced.

[0110] According to one embodiment, as shown in Figures 4 and 5, the nesting system 40 comprises a rib 41, 41' formed in one of the bridging plates 30 and projecting in the longitudinal direction A1 towards the bridging plate. adjacent bridging 30. The nesting system 40 then comprises a housing 42, 42' formed in this adjacent bridging plate 30 and receiving said rib 41, 41'.

[0111] The overlap clearance is for example defined by the smallest dimension among a depth of the housing 42, 42' and a length of the rib 41, 41'.

[0112] For example, in the embodiment shown in [Fig. 4], the nesting system 40 comprises a rib 41 formed in the first bridging plate 30 and projecting in the longitudinal direction A1 towards the second bridging plate 30. The nesting system 40 comprises a housing 42 formed in the second bridging plate 30 and receiving said rib 4L

[0113] According to this exemplary embodiment, the rib 41 of the first bridging plate 30 is delimited in part by one of the two main faces 31A, 31B of the first bridging plate 30, here the internal main face 31A, and in part by a recess 36 of the first longitudinal end surface 33A of the first bridging plate 30 ([Fig.4]). The housing 42 of the second bridging plate 30 opens onto the internal main face 31A of the second bridging plate 30.

[0114] The bottom of the recess 36 and the part of the longitudinal end surface 33A delimiting the rib 41 form the adjustment surfaces 34.

[0115] In the embodiment shown in [Fig. 5], the nesting system 40 comprises a rib 41', taking the form of a finger, formed in the second bridging plate 30 and projecting in the longitudinal direction A1 towards the first bridging plate 30. The nesting system 40 comprises a housing 42' formed in the first bridging plate 30 and receiving said rib 41'.

[0116] The rib 41' of the second bridging plate 30 is delimited by two recesses 36' of the longitudinal end surface 33B' of the second bridging plate 30 and the housing 42' of the first bridging plate 30 forms a groove in the longitudinal end surface 33A' of the first bridging plate 30.

[0117] The portion of the longitudinal end surface 33B' delimiting the rib 41' and the portion of the longitudinal end surface 33A' delimiting the groove 42' form two parallel adjustment surfaces 34'.

[0118] The sealing membrane 14 has an inner face 14A, intended to be in contact with the fluid contained in the tank, and an outer face 14B, facing the thermally insulating barrier 12 (figures 4 and 5).

[0119] As shown in [Fig.2] to 5, the sealing membrane 14 comprises at least one corrugation 15, 16 projecting from the side of the inner face of the sealing membrane.

[0120] More precisely, two series of undulations 15, 16 are provided, each extending respectively parallel to one of the peripheral faces 21A, 21B of the panels. insulators 13. The first series of corrugations 15 comprises at least two first parallel corrugations 15, projecting from the side of the inner face 14A of the waterproofing membrane 14, each first corrugation 15 extending in a first main direction d1 parallel to the first longitudinal peripheral faces 21A of the insulating panel 13 and each second corrugation 16 extending in a second main direction d2 parallel to the second transverse peripheral faces 21B of the insulating panel 13 ([Fig.2]).

[0121] The first main direction d1 is here parallel to the longitudinal axis of the insulating panel 13 while the second main direction d2 is orthogonal to this longitudinal axis.

[0122] The first series of corrugations 15 extends here in the longitudinal direction Al of the inter-panel spaces 25 described previously. The second series of corrugations 16, which are lower than the corrugations 15, extends in the transverse direction Al 1 of the inter-panel space 25, at the level of the interlocking system 40 of the bridging plates 30.

[0123] Indeed, as shown in [Fig.3], the length of the bridging plate 30 along the longitudinal direction A1 of the inter-panel space 25 is equal to the interval between two undulations of the second series of undulations 16.

[0124] As mentioned previously, the structure of the insulating panel 13 is identical at the level of the second transverse peripheral faces 21B which also delimit inter-panel spaces 25 ([Fig.2]). The arrangement of the bridging plates 30 described previously with reference to the inter-panel spaces 25 delimited by the first longitudinal peripheral faces 21A of the insulating panels 13 can therefore also be applied to the inter-panel spaces 25 delimited by the second transverse peripheral faces 21B.

[0125] The inter-panel spaces 25 delimited by the second transverse peripheral faces 21B also house an insulating joint 26 and the bridging plates 30 described previously can be arranged above this insulating joint.

[0126] The sealing membrane 14 is obtained by assembling a plurality of corrugated metal sheets, welded to each other overlapping along their edges. The first and second corrugations 15, 16 project towards the inside of the tank. The corrugated metal sheets are fixed on anchoring strips 29 which are fixed in counterbores formed in the cover plates 22 of the insulating panels 13. The corrugated metal sheets are, for example, made of stainless steel or aluminum.

[0127] As shown in Figures 2 to 8, the insulating panels 13 of the thermally insulating barrier 12 of the tank comprise first relaxation slots 50, extending in a thickness of the insulating panel 13, from the internal face 22A of the insulating panel 13, facing the first corrugations 15 of the waterproof membrane 14, and extending in the first main direction dl corresponding to the longitudinal direction Al of the inter-panel space 25. The first relaxation slots 50 comprise two first extreme relaxation slots 51, each first extreme relaxation slot 51 corresponding to the first relaxation slot closest to one of the two first longitudinal peripheral faces 21A of the insulating panel 13.

[0128] [Fig.7] shows more particularly one of the insulating panels 13 of the tank wall of [Fig.2]. In the case of this insulating panel 13, three first relaxation slots 50 are provided: a first central relaxation slot 50 extends in the middle of the insulating panel 13 along the longitudinal direction A1, and the two first extreme relaxation slots 51 extend close to the first peripheral faces 21A of the insulating panel 13, on either side of the first central relaxation slot 50.

[0129] The first undulations 15 are mutually spaced by a first undulation pitch PI ([Fig.2]).

[0130] The distance separating two first relaxation slots 50 is equal to that provided between two first undulations 15, i.e. equal to the first undulation pitch PL

[0131] According to one embodiment, a distance between a first extreme relaxation slot 51 and a first adjacent longitudinal peripheral face 21A of the insulating panel 13 is less than the first corrugation pitch PI, preferably equal to half of the first corrugation pitch PL

[0132]

[0133] The insulating panels 13 of the thermally insulating barrier 12 of the tank also comprise second relaxation slots 60, extending in the thickness of the insulating panel 13, from the internal face 22A of the insulating panel, opposite the second corrugations 16 of the sealing membrane 14, and extending in the second main direction d2 corresponding to the transverse direction Al 1 of the inter-panel space 25. The second relaxation slots 60 comprise two second extreme relaxation slots 61, each second extreme relaxation slot 61 corresponding to the second relaxation slot 60 closest to one of the two second transverse peripheral faces 21B of the insulating panel 13.

[0134] The second undulations 16 are mutually spaced by a second undulation pitch P2 ([Fig.2]). The first undulation pitch PI and the second undulation pitch P2 may be equal or different.

[0135] The distance separating two second relaxation slots 60 is equal to that provided between two second undulations 16, i.e. equal to the second undulation pitch P2.

[0136] According to one embodiment, a distance between a second extreme relaxation slot 61 and a second adjacent transverse peripheral face 21B of the insulating panel 13 is less than the second corrugation pitch P2, preferably equal to half of the second corrugation pitch P2.

[0137] Thanks to these characteristics, it is possible to obtain a positioning of the first and second corrugations 15, 16 which promotes the uniformity of the stresses applied to the different corrugations.

[0138] In the case of this insulating panel 13 of [Fig.7], nine second relaxation slots 60 are provided. The two second extreme relaxation slots 61 each extend respectively close to one of the second transverse peripheral faces 21B of the insulating panel 13.

[0139] The relaxation slots 50, 60 are thus arranged to allow deformation of the corrugation 15, 16 arranged directly above said relaxation slots 50, 60 in a direction transverse to their direction of extension.

[0140] Here, each first relaxation slot 50 crosses all the second relaxation slots 60 and extends between two ends 50A, 50B each located between one of the two second extreme relaxation slots 61 and the second transverse peripheral face 21B of the adjacent insulating panel 13, but at a distance from this second transverse peripheral face 21B.

[0141] Each second relaxation slot 60 intersects all the first relaxation slots 50 and extends between two ends 60A, 60B each located between one of the two first extreme relaxation slots 51 and the first longitudinal peripheral face 21A of the adjacent insulating panel 13, but at a distance from this first longitudinal peripheral face 21A.

[0142] The first and second relaxation slots 50, 60 have lengths less than the dimensions of the insulating panel 13 along their axis. In other words, the relaxation slots 50, 60 do not extend to the peripheral faces 21A, 21B of the insulating panel 13.

[0143] Thus, the internal face 22A of the insulating panel 13 comprises a continuous peripheral edge 221 ([Fig.7]), not interrupted by the first and second relaxation slots 50, 60. The continuous peripheral edge 221 extends between each first longitudinal peripheral face 21A of the insulating panel 13 and the ends 60A, 60B of the second relaxation slots 60 and between each second transverse peripheral face 21B of the insulating panel 13 and the ends 50A, 50B of the first relaxation slots 50.

[0144] The dimension of the peripheral edge 221 in a transverse direction, perpendicular to the first or second adjacent peripheral face 21A, 21B of the panel insulator 13, is between 5 and 50 millimeters.

[0145] In other words, the distance E between the end 50A, 50B, 60A, 60B of each of the first and second relaxation slots 50, 60 and the first or second peripheral face 21A, 21B of the adjacent insulating panel 13, is between 5 and 50 millimeters ([Fig. 8]).

[0146] Each first and second relaxation slot 50, 60 is for example obtained by cutting with a circular saw. The profile of such a relaxation slot 50, 60 is shown for example in [Fig.8].

[0147] Each first and second relaxation slot 50, 60 has a fillet at each of their ends corresponding to the rounded shape of the circular saw used.

[0148] Alternatively, the cutting of the relaxation slots 50, 60 can be carried out by means of a mortiser-type device or any other suitable device such as a milling device, guided chainsaw, annular saw or the like.

[0149] Each relaxation slot 50, 60 extends in a plane perpendicular to the internal face 22A of the insulating panel 13.

[0150] Each relaxation slot 50, 60 passes through the cover plate 22 of the insulating panel 13 and a portion of the polymer foam layer sandwiched between the cover plate 22 and the bottom plate 23, without reaching the bottom plate 23.

[0151] The depth of each relaxation slot 50, 60 is for example between 50 and 130 mm.

[0152] The first and second relaxation slots 50, 60 are thus here non-opening and non-through: they do not open onto any of the peripheral faces 21A, 21B of the insulating panel 13 and do not pass through the layer of insulating polymer foam 21.

[0153] The insulating panels 13 can be manufactured according to various embodiments. The cover 22 and bottom 23 plates are, for example, glued on either side of the insulating polymer foam layer 21 and then the relaxation slots 50, 60 are cut out.

[0154] The use of such an insulating panel 13 in the tank reinforces the sealing of the tank and the protection of the supporting structure IA against possible leaks of the fluid contained in the tank. Indeed, if fluid contained in the tank reaches the insulating panel 13 and manages to pass through the cover plate 22, this fluid will not be guided by one of the slots to the inter-panel space 25 because no slot in the insulating panel 13 opens onto this inter-panel space.

[0155] The nesting system provided at the junction of the bridging plates and the fact that the relaxation slots are non-opening on the peripheral faces of the insulating panel 13 contribute to reinforcing the sealing of the tank and the protection of the supporting structure, in this case the hull of the ship, against leaks of the fluid contained in the tank which could damage this supporting structure.

[0156] The use of non-opening relaxation slots 50, 60 on the peripheral faces 21A, 21B of the insulating panel 13 also makes it possible to limit the convection and thermosiphon phenomena inside the wall of the tank.

[0157] Alternatively, the insulating panel 13 may comprise relaxation slots 55, 65 opening onto the peripheral faces 21A, 21B of the insulating panel 13, as shown in [Fig.9].

[0158] In the particular example shown here, the tank comprises two different types of tank walls. In a first portion of the tank, the tank walls are single-barrier tank walls, while in a second portion of the tank, the tank walls comprise a double-barrier tank wall.

[0159] In the first part of the tank, the single barrier wall part 11 ([Fig. 1]) comprises the thermally insulating barrier 12 described above, comprising a plurality of identical and juxtaposed insulating panels 13, surmounted by the sealing membrane 14. The insulating panels 13 of the thermally insulating barrier 12 are fixed to the load-bearing wall 2, 3, 4, 5, 6, 7, 8, 9, 10 ([Fig. 2]). No additional sealing membrane is interposed between the insulating panels 13 and the load-bearing structure 1A.

[0160] The single barrier wall portion 11 is arranged in an upper portion of the tank, located above a substantially horizontal median plane PM of the tank.

[0161] Said single barrier wall portion 11 is more particularly arranged in the areas of the tank least in contact with the fluid contained in the tank. The risk of the load-bearing wall being exposed to the fluid contained in the tank is in fact lower in the upper part of the tank.

[0162] In practice, the single barrier wall part 11 is therefore anchored to an upper part of the supporting structure IA represented schematically by the horizontally dashed areas of [Fig.l], while the double barrier wall part 17 is anchored to a lower part of the supporting structure IA, represented schematically by the hatched areas of [Fig.l].

[0163] In particular, the single barrier wall portion 11 forms the ceiling of the tank.

[0164] The use of the bridging plates 30 described previously, provided with the nesting system and the use of relaxation slots 50, 60 not opening onto the peripheral faces 21A, 21B of the insulating panel 13 are particularly advantageous in the context of the production of this single barrier wall part 11.

[0165] The double barrier wall portion 17 is preferably used in areas of the tank that are particularly exposed to the fluid contained in the tank. The risk of the load-bearing wall being exposed to the fluid contained in the tank is greater in the lower part of the tank.

[0166] The double barrier wall portion 17 may be of any suitable type known to those skilled in the art. It successively has, from the outside to the inside, along the thickness direction of the wall:

[0167] - a secondary thermally insulating barrier comprising insulating elements fixed to the supporting structure;

[0168] - a secondary waterproofing membrane anchored to the insulating elements of the barrier secondary thermal insulation;

[0169] - a primary thermally insulating barrier comprising other insulating elements resting against the secondary waterproofing membrane; and

[0170] - a primary waterproofing membrane anchored to the insulating elements of the barrier primary thermal insulation and intended to be in contact with the fluid contained in the tank.

[0171] The primary waterproofing membrane is for example similar to that described previously.

[0172] The secondary waterproofing membrane can be made by various known techniques, for example in the form of a bonded composite sheet. According to another example, it is formed from a continuous sheet of strakes with raised edges. Each strake has a flat central portion resting on insulating elements of the secondary thermally insulating barrier and two raised edges projecting towards the inside of the tank. The strakes are welded by their raised edges to welding supports which are fixed in grooves formed in the insulating elements of the secondary thermally insulating barrier.

[0173] In a preferred embodiment, the insulating elements of the primary thermally insulating barrier are primary insulating panels of a similar structure to that of the insulating panel 13 of the single barrier wall portion 11. They comprise a layer of insulating polymer foam, for example polyurethane, sandwiched between a rigid cover plate and a base plate, for example plywood.

[0174] In order to ensure the continuity of the tank wall, the thickness of each insulating panel 13 forming the single barrier wall portion 11 is equal to the cumulative thickness of the primary and secondary thermally insulating barriers and of the secondary sealing membrane of the double barrier wall portion so that the internal face of the insulating panels 13 of the single barrier wall portion 11 extends in the extension of an internal face of the insulating panels forming the primary thermally insulating barrier of the double barrier wall portion.

[0175] For example, the insulating panel 13 has a length of 3 meters and a width of 1 meter. The plywood cover plate 22 may have a thickness of between 9 and 15 mm; the plywood bottom plate 23 may have a thickness of between 9 and 15 mm, and the layer of insulating polymer foam 21 has a thickness suitable for obtaining an insulating panel having a total thickness of approximately 200 to 500 mm, for example 400 mm thick. Of course, the dimensions and thicknesses are given for information purposes only and vary depending on the applications and the desired thermal insulation performance.

[0176] The thickness of each of the primary and secondary barriers of the double barrier wall portion 17 may be about 200 mm in this case.

[0177] The waterproofing membrane 14 of the single barrier wall portion 11 and the primary waterproofing membrane of the double barrier wall portion 17 thus extend in line with each other. The waterproofing membrane 14 of the single barrier wall portion 11 and the primary waterproofing membrane of the double barrier wall portion 17 are formed from corrugated plates welded to each other overlapping along their edges so as to form only one continuous waterproofing membrane.

[0178] The technique described above for producing a sealed and insulating tank can be used in different types of tanks, for example to form the wall of an LNG tank in a land-based installation or in a floating structure such as an LNG carrier or other. It can also be used to produce a fuel tank for the propulsion system of a ship, for ships of all kinds. In such a case, the liquefied gas contained in the tank is subsequently called liquefied fuel gas.

[0179] [Fig. 10] shows a schematic view of a ship 70 comprising a sealed and thermally insulating tank 1 mounted in the hull 72 of the ship 70. In a manner known per se, loading pipelines of the ship can be connected, by means of appropriate connectors, to a maritime or port terminal to transfer a cargo of liquefied combustible gas to the tank 1.

[0180] [Fig. 10] shows an example of a maritime terminal comprising a loading and unloading station 75, a subsea pipeline 76 and a land-based installation 77. The loading station 75 is a fixed offshore installation comprising a mobile arm 74 and a tower 78 which supports the mobile arm 74. The mobile arm 74 carries at least one flexible pipe 79 which can be connected to the loading pipeline of the ship. The orientable mobile arm 74 adapts to all sizes of ship. A connecting pipeline (not shown) extends inside the tower 78. The loading station 75 allows the ship 70 to be loaded with LNG fuel from the land-based installation 77. The latter comprises liquefied gas storage tanks 80 and connecting pipelines 81 connected by the subsea pipeline 76 to the loading station 75.The underwater pipeline 76 allows the transfer of liquefied gas between the loading station 75 and the onshore installation 77 over a long distance, for example. 5 km, which allows the vessel 70 to be kept at a great distance from the coast during loading operations.

[0181] To generate the pressure necessary for the transfer of the liquefied gas, pumps on board the ship 70 and / or pumps equipping the onshore installation 77 and / or pumps equipping the loading station 75 are used.

[0182] Although the invention has been described in connection with several particular embodiments, it is quite obvious that it is in no way limited thereto and that it includes all the technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.

[0183] The use of the verb “comprise”, “comprise” or “include” and its conjugated forms does not exclude the presence of other elements or other steps than those set out in a claim.

[0184] In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims

Claims

1. A sealed and thermally insulating tank (1) for storing a fluid, the tank (1) comprising a tank wall fixed to a load-bearing wall (2, 3, 4, 5, 6, 7, 8, 9, 10), the tank wall comprising a sealing membrane (14) and a thermally insulating barrier (12) arranged between the sealing membrane (14) and the load-bearing wall, - the sealing membrane (14) having an inner face (14A), intended to be in contact with the fluid contained in the tank (1), and an outer face (14B), facing the thermally insulating barrier (12), - the thermally insulating barrier (12) comprising at least two insulating panels (13) each having an inner face (22A) facing the inside of the tank (1) and covered by the sealing membrane (14), the two insulating panels (13) being juxtaposed to delimit a inter-panel space (25) between them, said inter-panel space (25) extending in a longitudinal direction (Al),the thermally insulating barrier (12) comprising at least one insulating joint (26) housed in the inter-panel space (25) and bridging plates (30) arranged above the at least one insulating joint (26) so as to extend astride the two insulating panels (13) in a transverse direction (A11) of the inter-panel space (25), each bridging plate (30) having an elongated shape in the longitudinal direction (A1) of the inter-panel space (25), each bridging plate (30) being provided with two main faces (31A, 31B) parallel to the internal face of the thermally insulating barrier (12) and connected by two transverse end surfaces (32) and by two longitudinal end surfaces (33A, 33B; 33A', 33B'), the longitudinal end surfaces (33A, 33B ; 33A', 33B') being located at the longitudinal ends of the bridging plate (30),characterized in that a longitudinal end surface (33A; 33A') of a first of the bridging plates (30) and a longitudinal end surface (33B; 33B') of a second of the bridging plates (30) arranged opposite the longitudinal end surface (33A; 33A') of the first bridging plate (30) have an interlocking system (40) which extends astride the two insulating panels (13) in the transverse direction (A11) of the inter-panel space (25) to extend a flow path between the first and second, bridging plates (30).

2. Tank according to claim 1, in which the two longitudinal end surfaces (33A, 33B; 33A', 33B') of each bridging plate (30) have shapes complementary to each other capable of forming said nesting system (40).

3. Tank according to one of claims 1 to 2, in which said nesting system (40) has an overlap clearance greater than 10 mm in the longitudinal direction (Al) of the inter-panel space (25).

4. Tank according to one of claims 1 to 3, in which at least one of the longitudinal end surfaces (33A, 33B; 33A', 33B') of each bridging plate (30) has at least one adjustment surface (34, 34') parallel to the main faces (31 A, 31B) of the bridging plate (30).

5. Tank according to claim 4, in which the at least one adjustment surface (34, 34') is connected to at least one of the two main faces (31 A, 31B) of the bridging plate (30) by a connecting surface perpendicular to the main face (31 A, 31B).

6. Tank according to one of claims 1 to 5, in which the nesting system (40) comprises a rib (41, 41') formed in the first bridging plate (30) and projecting in the longitudinal direction (A1) towards the second bridging plate (30), and a housing (42, 42') formed in the second bridging plate (30) and receiving said rib (41, 41').

7. Tank according to claim 6, in which the rib (41) of the first bridging plate (30) is delimited partly by one of the two main faces (31 A, 31B) of the first bridging plate (30) and partly by a step (36) of the longitudinal end surface (33A, 33B) of the first bridging plate (30), and in which the housing (42) of the second bridging plate (30) opens onto a corresponding main face (31 A, 31B) of the second bridging plate (30).

8. Tank according to one of claims 6, in which the rib (41') of the first bridging plate (30) is delimited by two recesses (36') of the longitudinal end surface (33A', 33B') of the first bridging plate (30) and the housing (42') of the second bridging plate (30) forms a groove in the longitudinal end surface (33A', 33B') of the second bridging plate (30).

9. Tank according to one of claims 1 to 8, in which the membrane sealing membrane (14) comprises at least one corrugation (15, 16) projecting from the side of the inner face (14A) of the sealing membrane (14), said corrugation (15, 16) extending in a direction orthogonal (Ail) to the longitudinal direction (Al) of the inter-panel space (25) at right angles to the nesting system (40).

10. Tank according to one of claims 1 to 9, in which the tank wall comprises a single barrier wall portion (11), the single barrier wall portion comprising said insulating panel (13) juxtaposed with a plurality of identical insulating panels (13) forming a thermally insulating barrier (12) surmounted by the sealing membrane (14), said thermally insulating barrier (12) being fixed to the load-bearing wall (2, 3, 4, 5, 6, 7, 8, 9, 10), without any other sealing membrane interposed between the thermally insulating barrier (12) and the load-bearing wall.

11. Tank according to claim 10, wherein said single barrier wall portion (11) is arranged in an upper portion of the tank, located above a substantially horizontal median plane (PM) of the tank (1).

12. A tank according to claim 11, wherein said single barrier wall portion (11) forms the ceiling of the tank.

13. Tank according to one of claims 10 to 12, in which the tank wall further comprises a double barrier wall portion (17) comprising a primary sealing membrane intended to be in contact with the fluid contained in the tank, a secondary sealing membrane arranged between the primary sealing membrane and the load-bearing wall, a primary thermally insulating barrier (12) arranged between the primary sealing membrane and the secondary sealing membrane and a secondary thermally insulating barrier (12) arranged between the secondary sealing membrane and the load-bearing wall,wherein the thickness of each insulating panel (13) forming the single barrier wall portion (11) is equal to the cumulative thickness of the primary and secondary thermally insulating barriers (12) and of the secondary sealing membrane of the double barrier wall portion such that the inner face of the insulating panels (13) of the single barrier wall portion (11) extends in the extension of an inner face of insulating panels forming the primary thermally insulating barrier (12) of the double barrier wall portion, and wherein the sealing membrane (14) of the wall portion, single barrier (11) and the primary waterproofing membrane of the double barrier wall portion (17) extend in line with each other.

14. Tank according to one of claims 1 to 12, in which: - each insulating panel (13) has four peripheral faces (21A, 21B) extending from said internal face (22A), - the waterproofing membrane (14) comprises first corrugations (15) extending in a first main direction (dl) parallel to the longitudinal direction of the inter-panel space (25), - the sealing membrane (14) further comprising second parallel corrugations (16) extending in a second main direction (d2) orthogonal to the longitudinal direction (Al) of the inter-panel space (25), the insulating panel comprising: - first relaxation slots (50), extending in a thickness of the insulating panel, from the internal face (22A) of the insulating panel (13), opposite the first corrugations (15) of the sealing membrane (14), in the first main direction (dl) and comprising two first extreme relaxation slots (51), each first extreme relaxation slot (51) corresponding to the first relaxation slot (50) closest to one of the two first peripheral faces (21A, 21B) of the insulating panel (13) and - second relaxation slots (60), extending in the thickness of the insulating panel (13), from the internal face (22A) of the insulating panel (13), opposite the second corrugations (16) of the sealing membrane (14), in the second main direction (d2), and comprising two second extreme relaxation slots (61), each second extreme relaxation slot (61) corresponding to the second relaxation slot (60) closest to one of the two second peripheral faces (21A, 21B) of the insulating panel (13), in which each first relaxation slot (50) intersects all the second relaxation slots (60) and extends between two ends (50A, 50B) each located between one of the two second extreme relaxation slots (61) and the adjacent second peripheral face (21B) of the insulating panel (13), at a distance from said second peripheral face (21B),and each second relaxation slot (60) intersects all the first relaxation slots (50) and extends between two ends (60A, 60B), each located between one of the two first extreme relaxation slots (51) and the first peripheral face (21 A) of the adjacent insulating panel (13), at a distance from said first peripheral face (21A).

15. A ship (70) comprising a hull (72), a propulsion system and a sealed and thermally insulating tank (1) according to one of claims 1 to 14, for storing a liquefied combustible gas intended to supply the combustible gas to the propulsion system.

16. A transfer system for a liquefied fuel gas, the system comprising a vessel (70) according to claim 15, insulated pipes (79, 76, 81) arranged to connect the tank (1) of the vessel (70) to a floating or land-based storage facility (77) and a pump for driving a flow of liquefied fuel gas through the insulated pipes (79, 76, 81) from the floating or land-based storage facility (77) to the tank (1) of the vessel (70).

17. A method of loading a ship (70) according to claim 15, wherein a liquefied combustible gas is conveyed through insulated pipes (79, 76, 81) from a floating or land-based storage facility (77) to the tank of the ship (70).

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