Method for manufacturing an insulating barrier for a tank

Abstract

The present invention relates to a method for manufacturing an insulating barrier (5) for a wall (1) of a sealed insulated tank that is fixed to a support structure (2), the method comprising the steps of: fixing a plurality of insulating panels (11) with at least one fixing device (12), the plurality of insulating panels (11) having a receiving portion (18) in which the fixing device (12) is received; inserting an insulating stopper (25) into the receiving portion (18) and pushing the insulating stopper (25) toward the support structure (2) until the insulating stopper (25) is pressed against a bearing surface toward the support structure (2); and trimming the insulating stopper (25) so that its inner end is flush with the inner surface of the plurality of insulating panels (11).

Description

[Technical Field]

[0001] The present invention relates to the field of sealed, insulated tanks for storing and / or transporting liquefied gases, such as tanks for transporting liquefied petroleum gas (also called LPG) at temperatures between -50°C and 0°C or for transporting liquefied natural gas (LNG) at approximately -162°C and atmospheric pressure.

[0002] These tanks may be located on land or on floating structures, in which case the tanks may be intended for the transport of liquefied gas or for the storage of liquefied gas as fuel for the propulsion of the floating structure. [Background technology]

[0003] WO 19 / 092384 discloses a method for manufacturing an insulating barrier for the wall of a sealed, insulated tank. The tank wall has a multilayer structure including, in succession across the thickness from the outside to the inside of the tank, a secondary insulating barrier having insulating panels supported on a support structure, a secondary sealing membrane mounted on the secondary insulating barrier, a primary insulating barrier having insulating panels mounted on the secondary sealing membrane, and a primary sealing membrane mounted on the primary insulating barrier and configured to contact the liquefied natural gas contained in the tank. Each insulating panel of the primary insulating barrier has cutouts along its edge at its corners. These cutouts define recesses that accommodate fastening devices for fastening the insulating panels of the primary insulating barrier to the insulating panels of the secondary insulating barrier. To ensure continuity of thermal insulation, an insulating stopper having a layer of insulating polymer foam is received in a recess formed in the primary insulating barrier. To achieve this, the document describes inserting each insulating stopper into its respective receiving section and forcing the stopper toward the support structure until the stopper strikes the support member received in the receiving section and irreversibly damages the stopper, and the stopper is pushed in until its inner end reaches a predetermined position in the receiving section.

[0004] This prevents the insulating stopper from causing local differences in level (height) that would adversely affect the flatness of the support surface of the primary sealing membrane, even if there are large manufacturing tolerances for the dimensions of the insulating stopper.

[0005] However, this method is not entirely satisfactory, in particular because forcing the insulating stopper until it is irreversibly deformed requires the application of considerable force on the part of the operator, thereby increasing the manufacturing time of the insulating barrier and worsening the working conditions of the operator, especially when the polymer foam of the insulating stopper is of high density. Summary of the Invention

[0006] The idea behind the present invention is to provide a method for manufacturing an insulating barrier configured to define an inner support surface for a sealing membrane, the insulating barrier having a receiving portion and an insulating stopper received in the receiving portion, which is simple to implement and limits the presence of level differences on the inner support surface of the sealing membrane that is aligned with the receiving portion.

[0007] In one embodiment, the present invention provides a method for manufacturing an insulating barrier for a wall of a sealed, insulated tank secured to a support structure, the method comprising the steps of: securing, directly or indirectly, a plurality of insulating panels to the support structure by at least one fastening device, the plurality of insulating panels defining an inner surface configured to support a sealing membrane and having a receiving portion opening on the inner surface, the receiving portion receiving the fastening device; and providing an insulating stopper configured to ensure thermal continuity in the receiving portion, the insulating stopper having an inner end and an outer end, the insulating stopper having a front end. The method includes the steps of inserting the insulating stopper into the receiving portion and pushing the insulating stopper toward the support structure until the outer end of the insulating stopper is pressed against a bearing surface spaced from the inner surfaces of the plurality of insulating panels by a distance d2, which is less than d1, toward the support structure, and trimming the inner hard sheet of the insulating stopper so that the inner end of the insulating stopper is flush with the inner surfaces of the plurality of insulating panels.

[0008] Such a method is therefore particularly simple, since no great pressure is required to deform the insulating stopper and the dimensional tolerances of the stopper can be large, since this is not critical in the proposed method. Furthermore, this method makes it possible to prevent the insulating stopper from causing local level differences on the support surface of the sealing membrane.

[0009] In embodiments, such a method may have one or more of the following features:

[0010] In one embodiment, the inner rigid sheet is made of plywood.

[0011] In one alternative embodiment, the inner rigid sheet is adhesively bonded to the insulating polymer foam layer, for example by polyurethane or epoxy adhesive.

[0012] In another alternative embodiment, the inner rigid sheet is stapled to the insulating polymer foam layer.

[0013] In one embodiment, the fixing device housed inside the housing comprises a pin that is fixed directly or indirectly to the support structure, a retaining member is attached to the pin when fixing the insulation panels, whereby the retaining member cooperates with at least one retention zone of the insulation panel to hold the insulation panel against the support structure, and a nut is screwed onto the pin to secure the retaining member to the pin.

[0014] In one embodiment, the retaining member forms a bearing surface against which the outer end of the insulating stopper presses.

[0015] In one embodiment, the insulating stopper has an outer hard sheet having an outer surface forming the outer edge of the insulating stopper and an inner surface contacting the insulating polymer foam layer of the insulating stopper, the outer hard sheet having a recess formed in its outer surface for receiving a nut of a fastener, which allows the insulating polymer foam layer to better absorb compressive forces.

[0016] In one embodiment, the inner surface of the outer rigid sheet at least partially covers the recess.

[0017] In one embodiment, the outer hard sheet has a hole that opens into the recess and receives one end of the pin, the hole having a diameter smaller than the diameter of the recess.

[0018] In one embodiment, the holes are blind holes.

[0019] In one embodiment, the outer rigid sheet is secured to the insulating polymer foam layer.

[0020] In one alternative embodiment, the outer rigid sheets are adhesively bonded to the insulating polymer foam layer, for example by polyurethane or epoxy adhesive.

[0021] In another alternative embodiment, the outer rigid sheet is stapled to the insulating polymer foam layer.

[0022] In another embodiment, the outer rigid sheet is free relative to the insulating polymer foam layer, and inserting the insulating stopper into the housing includes a phase of inserting the outer rigid sheet into the housing and then a phase of inserting the insulating polymer foam layer into the housing.

[0023] In another embodiment, the outer rigid sheet is made of a material having a thickness equal to the thickness of the inner rigid sheet to be trimmed. e A selection is made from a number of outer hard sheets having different thicknesses so as to limit the thickness d1-d2.

[0024] In one embodiment, the insulating polymer foam layer has a density of 100 kg / m 3 to 260 kg / m 3 It is between.

[0025] In one embodiment, the outer rigid sheet is stapled to one of the insulation panels.

[0026] In another form, the present invention also provides a thermal insulation barrier for a wall of a sealed insulated tank fixed to a support structure, the thermal insulation barrier comprising: a plurality of insulating panels fixed directly or indirectly to the support structure by at least one fastening device, the plurality of insulating panels defining an inner surface configured to support a sealing membrane and having a receiving portion opening on the inner surface, the receiving portion receiving the fastening device; a fastening device received inside the receiving portion, the fastening device being a pin fixed directly or indirectly to the support structure; a retaining member attached to the pin to cooperate with at least one retaining zone of the insulating panel; and a nut screwed onto the pin to secure the retaining member to the pin. and an insulating stopper configured to ensure thermal continuity in the receiving portion, wherein the insulating stopper has an insulating polymer foam layer, an inner hard sheet fixed to the insulating polymer foam layer and forming an inner end of the insulating stopper, and an outer hard sheet, wherein the outer hard sheet has an inner surface in contact with the insulating polymer foam layer of the insulating stopper and an outer surface forming the outer end of the insulating stopper and being pressed against the support structure by the retaining member, and the outer hard sheet has a recess formed in its outer surface, in which a nut of the fixing device is received, and the inner surface of the outer hard sheet at least partially covers the recess.

[0027] Such a configuration therefore provides a larger bearing zone for the insulating polymer foam layer, i.e. a zone through which compressive forces pass under the influence of mechanical and hydrostatic pressures of the liquid contained in the tank, which allows the insulating polymer foam layer to better absorb compressive forces without the need for a higher density.

[0028] In one embodiment, the invention relates to a tank wall having an insulating barrier as described above and a sealing membrane mounted on the insulating barrier and configured to be in contact with a fluid contained within the tank.

[0029] In one embodiment, the present invention relates to a sealed, insulated tank having a wall as described above.

[0030] A tank according to one of the above-mentioned embodiments may form part of a land-based storage facility, for example for storing LNG, or may be installed on an onshore or offshore floating structure, in particular an ethane or methane tanker, a floating storage and regasification unit (FSRU), a floating production, storage and offloading (FPSO) unit, etc. In the case of a floating structure, the tank may be configured to contain liquefied natural gas to fuel the propulsion of the floating structure.

[0031] In one embodiment, the aforementioned insulating barrier is a primary insulating barrier and the tank wall further comprises a secondary insulating barrier and a secondary sealing membrane disposed between the primary and secondary insulating barriers.

[0032] In one embodiment, a vessel for transporting fluids has a hull, such as a double hull, and the tanks described above disposed within the hull.

[0033] In one embodiment, the present invention also provides a method for loading and unloading such a vessel, wherein fluid is transferred via an insulated pipeline from a floating or onshore storage facility to the vessel's tanks or from the tanks to the floating or onshore storage facility.

[0034] In one embodiment, the present invention also provides a transfer system for a fluid, the system comprising a vessel as described above, an insulated pipeline arranged to connect a tank installed within the hull of the vessel to a floating or onshore storage facility, and a pump causing a flow of fluid from the floating or onshore storage facility to the vessel's tank or from the vessel's tank to the floating or onshore storage facility via the insulated pipeline.

[0035] The invention will be better understood and further objects, details, features and advantages thereof will become more apparent from the following description of some particular embodiments of the invention, given purely by way of non-limiting example with reference to the accompanying drawings, in which: [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is a cutaway perspective view of the wall of a sealed, insulated tank. [Figure 2] FIG. 2 is a cross-sectional view of the insulating barrier according to the first embodiment, taken through the insulating stopper. [Figure 3] FIG. 10 is a cross-sectional view of a thermal barrier according to a second embodiment, taken through the thermal stopper. [Figure 4] 1 is a cutaway schematic view of a ship having tanks for storing liquefied natural gas and a terminal for loading and unloading the tanks; [Figure 5] FIG. 10 is a cutaway perspective view of a wall of a sealed, insulated tank according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0037] By convention, the terms "exterior" and "interior" are used to define the relative position of one element to another with respect to the exterior and interior of the tank.

[0038] 1 shows the multi-layer structure of a wall 1 of a sealed, insulated tank for storing a fluid such as liquefied natural gas (LNG). Each wall 1 of the tank comprises, in succession across its thickness, from the outside to the inside of the tank, a secondary insulating barrier 3 supported on a support structure 2, a secondary sealing membrane 4 resting on the secondary insulating barrier 3, a primary insulating barrier 5 resting on the secondary sealing membrane 4, and a primary sealing membrane 6 configured to be in contact with the liquefied natural gas contained within the tank.

[0039] The support structure 2 may in particular comprise a self-supporting metal sheet, or more generally any type of rigid bulkhead with suitable mechanical properties. The support structure 2 may in particular be formed by the hull or double hull of a ship. The support structure 2 comprises a number of walls that define the overall shape of the tank, and is usually polyhedral in shape.

[0040] The secondary insulation barrier 3 comprises a plurality of secondary insulation panels 7 secured to the support structure 2 by resin beads and pins welded to the support structure 2. The secondary insulation panels 7 are generally rectangular parallelepiped shaped and arranged in parallel rows spaced apart from one another to provide functional mounting clearance. The spaces are filled with an insulating filler material, such as glass wool, rock wool, or open-cell flexible synthetic foam. Each secondary insulation panel 7 comprises a polymer foam layer 8 sandwiched between an inner sheet 9 and an outer sheet 10, which may be, for example, a sheet of plywood adhesively bonded to the polymer foam layer 8. The polymer foam 8 may be, in particular, a polyurethane-based foam, optionally reinforced with fibers, such as glass fibers.

[0041] In the illustrated embodiment, the secondary sealing membrane 4 comprises a continuous nappe of metal strakes with raised edges. The strakes are welded by their raised edges to parallel weld supports fixed in grooves formed in the inner sheet 9 of the secondary insulation panel 7. The strakes may be made of, for example, Invar®, a material with a coefficient of expansion typically of 1.2 x 10 -6 / K to 2×10 -6 It is made from an alloy of iron and nickel, which is / K.

[0042] In another embodiment (not shown), the secondary sealing membrane 4 comprises a number of corrugated metal sheets, each of which has a generally rectangular shape and which are lap-welded to one another, and which are in turn welded to a metal plate fixed to the inner sheet 9 of the secondary insulation panel 7. The corrugations may, for example, protrude towards the outside of the tank and be accommodated in grooves formed in the inner sheet 9 of the secondary insulation panel 7.

[0043] Additionally, the primary insulation barrier 5 includes a plurality of primary insulation panels 11, each having a generally rectangular parallelepiped shape, that are offset relative to the secondary insulation panels 7 of the secondary insulation barrier 3, such that each primary insulation panel 11 is staggered over four secondary insulation panels 7. The primary insulation panels 11 are secured to the secondary insulation panels 7 by fastening devices 12, as will be described below.

[0044] In the illustrated embodiment, each primary insulation panel 11 comprises a polymer foam layer 13 sandwiched between two rigid sheets, specifically an outer sheet 15 and an inner sheet 14. The outer sheet 15 and inner sheet 14 may be constructed of, for example, plywood. The polymer foam layer 13 may be, for example, polyurethane foam, optionally reinforced with fibers such as glass fibers.

[0045] The primary sealing membrane 6 is obtained by assembling a number of corrugated metal sheets, each of which has a substantially rectangular shape. The corrugations protrude towards the inside of the tank. The corrugated metal sheets of the primary sealing membrane 6 are arranged offset relative to the primary insulation panels 11, so that each of the corrugated metal sheets extends conjointly over four adjacent primary insulation panels 11. The corrugated metal sheets are lap-welded to one another and are welded along their edges to a metal plate fixed to the primary insulation panels 11, more particularly to their inner sheets 14. The inner sheets 14 of the primary insulation panels 11 define the inner support surface of the primary sealing membrane 6.

[0046] 1, each primary insulation panel 11 has a recess 16 at each corner thereof. Each recess 16 extends through the inner sheet 14 and through the entire thickness of the polymer foam layer 13.

[0047] 2, in each recess 16, the outer sheet 15 protrudes beyond the polymer foam layer 13 and beyond the inner sheet 14 to form a bearing zone 17 that cooperates with the fastening device 12. Each recess 16 formed in one corner of a primary insulation panel 11 is positioned opposite recesses 16 formed in the corners of three adjacent primary insulation panels 11, such that the four recesses 16 together define a receiving section 18 in the primary insulation barrier 5. Thus, one fastening device 12 positioned in this receiving section 18 can cooperate with four bearing zones 17 belonging to four adjacent primary insulation panels 11, respectively.

[0048] In the embodiment shown, cleats 19, for example made of plywood, are fixed to the bearing zone 17 of each primary insulation panel 11 to stiffen the primary insulation panel 11.

[0049] In the illustrated embodiment, each receptacle 18 is formed by a plurality of recesses 16 formed in the corners of the primary insulation panel 11. However, in other embodiments not shown, each receptacle 18 is not formed in the edge or one of the corners of the primary insulation panel 11, but instead is formed through the polymer foam layer 13 of one primary insulation panel 11.

[0050] In the illustrated embodiment, each fastening device 12 has a pin 20 protruding from a metal plate (not shown) fixed to the inner sheet 9 of one of the secondary insulation panels 7. Each pin 20 passes through an orifice formed in the secondary sealing membrane 4, which is also hermetically welded to the metal plate all around the periphery of the orifice, thereby sealing the penetration of the pin 20 in the secondary sealing membrane 4.

[0051] 2, each fixing device 12 has a retaining member 21 that is fixed to each pin 20 and that is pressed against the bearing zone 17 of each of the four adjacent primary insulation panels 11, in this example via cleats 19. Furthermore, a fixing member such as a nut 22 cooperates with the threads of the pins 20 and presses against the inner surface of the retaining member 21, thereby fixing the retaining member 21 to the pins 20 and thus exerting a holding force on the bearing zones 17. By way of example, the nuts 22 are split nuts, which have the advantage that they do not loosen during operation.

[0052] In the embodiment of FIG. 2, the fixed member 21 is an annular plate having an orifice that fits over the pin 20 .

[0053] Additionally, in an embodiment not shown, one or more resilient washers, such as Belleville washers, are attached to the pin 20 between the nut 22 and the retaining member 21, thereby resiliently securing the primary insulation panel 11 to the secondary insulation panel 7.

[0054] The primary insulating barrier 5 comprises an insulating stopper 25 adapted to be inserted into the receiving portion 18 to ensure continuity of the insulating properties. The insulating stopper 25 comprises an insulating polymer foam layer 23. The insulating polymer foam layer 23 may be, for example, polyurethane foam, optionally reinforced with fibres such as glass fibres. The insulating polymer foam layer 23 may have a density of 100 kg / m 3 to 260 kg / m 3 between 110 kg / m 3 to 150 kg / m 3 For example, it is between about 130 kg / m 3 is.

[0055] The insulating stopper 25 further includes an inner rigid sheet 24, made of, for example, plywood, that forms the inner edge of the insulating stopper 25. The inner rigid sheet 24 is advantageously adhesively bonded to the insulating polymer foam layer 23, for example, by a polyurethane or epoxy adhesive. In another alternative embodiment, the inner rigid sheet 24 is stapled to the insulating polymer foam layer 23. In such a case, the staples are advantageously spaced from the inner surface of the inner rigid sheet 24, for example, by being placed in cavities formed in the inner surface of the inner rigid sheet 24, so as not to impair the subsequent scraping operation described below.

[0056] The insulating stopper 25 has an outer end which is pressed towards the support structure 2 against a bearing surface housed in the housing 18. In the embodiment shown, the bearing surface is formed by the fixing member 21. The bearing surface is located at a distance d2 from the inner bearing surface of the primary sealing membrane 6.

[0057] 2, insulating stopper 25 has a recess 26 that opens at an outer end of insulating stopper 25, within which nut 22 of fastener 12 resides. Insulating stopper 25 also has a blind hole 27 that opens into recess 26 and receives the end of pin 20. Initially, insulating stopper 25 has a dimension d1 between the inner and outer ends of insulating stopper 25, measured in the thickness direction of wall 1. Dimension d2 is less than d1.

[0058] During manufacture of the primary insulating barrier 5, the insulating stopper 25 is inserted into the receiving portion 18 and then pushed towards the support structure 2 until the outer end of the insulating stopper 25 is pressed against the bearing surface, i.e., against the fixing member 21.

[0059] Next, the inner hard sheet 24 has a thickness e=d1-d2 toThe inner rigid sheet 24 is trimmed so that its inner surface is flush with the inner support surface of the primary sealing membrane 6. This operation therefore allows the inner surface of the inner rigid sheet 24 of the insulation stopper 25 to be at the same level as the inner surface of the primary insulation panel 11. This trimming operation is carried out, for example, by means of a planer. A planer typically comprises one or more handles, a sole configured to cooperate with the surface to be planed (in this example, the inner surface of the inner rigid sheet 24), and a tool flush with the sole for machining the surface to be planed. In one embodiment, the tool is a roller fitted with a blade or milling cutter, which is driven to rotate by a motor.

[0060] Finally, an inner rigid sheet 24 is secured to the primary insulation barrier 5 to maintain the insulating stop 25 in place. For this purpose, the inner rigid sheet 24 is secured to one of the four primary insulation panels 11 that abut the receptacle 18, for example by one or more staples arranged to span between the inner rigid sheet and one of the primary insulation panels 11.

[0061] Such a method is advantageous in that the insulating stoppers 25 prevent localized level differences that adversely affect the flatness of the support surface of the primary sealing membrane 6 .

[0062] 3 shows another embodiment of an insulating stopper 25. As with the previous embodiment, the insulating stopper 25 has an inner rigid sheet 24 that is trimmed so that its inner surface is flush with the inner support surface of the primary sealing membrane 6.

[0063] However, the insulating stopper 25 of the embodiment of Figure 3 differs from the embodiment described above with respect to Figure 2 in that it comprises an outer rigid sheet 28, for example made of plywood. The outer rigid sheet 28 has an outer surface that forms the outer edge of the insulating stopper 25 and is therefore configured to press against the bearing surface toward the support structure 2, i.e., against the fixing member 21 in the illustrated embodiment. The outer rigid sheet 28 has an inner surface that contacts the insulating polymer foam layer 23. In one embodiment, the outer rigid sheet 28 is adhesively bonded to the insulating polymer foam layer, for example by a polyurethane or epoxy adhesive. Alternatively, the outer rigid sheet 28 is stapled to the insulating polymer foam layer 23.

[0064] In another embodiment, the insulating stopper 25 is made up of two parts that are free relative to each other, with an outer rigid sheet 28 for one part and an insulating polymer foam layer 23 and an inner rigid sheet 24 for the other part. In this case, the insulating stopper 25 is inserted into the receiving part in two stages. In a first stage, the outer rigid sheet 28 is inserted into the receiving part 18 and pushed towards the support structure 2 until it presses against the fixing member 21. In a second stage, the insulating polymer foam layer 23 and the inner rigid sheet 24 are inserted into the receiving part 18 and then the insulating polymer foam layer 23 is pushed towards the support structure 2 until it presses against the outer rigid sheet 28.

[0065] Additionally, the outer hard sheet 28 is provided with a recess 29 formed in its outer surface for receiving the nut 22 of the fastener 12. In the illustrated embodiment, the outer hard sheet 28 also has a hole 30 of a smaller diameter than the diameter of the recess 29 for receiving the end of the pin 20. The hole 30 may be a through hole, i.e., a hole that passes through the inner surface of the outer hard sheet 28, or a blind hole, i.e., a hole that does not pass through the inner surface of the outer hard sheet 28. In either case, the inner surface of the outer hard sheet 28 at least partially covers the recess 29.

[0066] With such a configuration, the bearing zone of the insulating polymer foam layer 23, i.e. the zone in the insulating polymer foam layer 23 through which compressive forces pass under the influence of mechanical and hydrostatic pressures exerted by the liquid contained in the tank, is therefore larger than in the embodiment of Figure 2. This makes it possible to prevent or to make to a lesser extent fractures of the insulating polymer foam layer 23, and to allow said insulating polymer foam layer 23 to better absorb compressive forces without the need for a higher density.

[0067] In a variation of the embodiment of FIG. 3, the operator may have a set of multiple outer hard sheets 28 having different thicknesses and may select the thickness of the inner hard sheet 24 to be scraped. e The outer hard sheet 28 is selected to have a thickness that can limit =d1-d2.

[0068] Once the outer rigid sheet 28 is selected, in one embodiment, the outer rigid sheet 28 is then secured to the insulating polymer foam layer 23 by adhesive bonding, by stapling, or by one or more screws.

[0069] Figure 5 shows a tank wall according to another embodiment, which differs from the embodiment described above with respect to Figure 1 in that each of the primary insulation panels 11 is aligned with one of the secondary insulation panels 7 and is aligned with the secondary insulation panels 7 in the thickness direction of the wall 1.

[0070] Therefore, fixing devices are preferably arranged at the four corners of the secondary insulation panels 7 and the primary insulation panels 11. Each stack of secondary insulation panels 7 and primary insulation panels 11 is therefore fixed to the support structure 2 by four fixing devices. Furthermore, each fixing device cooperates with a corner of four adjacent secondary insulation panels 7 and a corner of four adjacent primary insulation panels 11.

[0071] Furthermore, in this embodiment, the primary sealing membrane 6 comprises a continuous expanse of metal strakes with raised edges. Also, like the secondary sealing membrane 4 in the embodiment of Figure 1, the metal strakes may be welded by their raised edges to parallel weld supports secured within grooves formed in the inner sheet of the primary insulation panel 11.

[0072] Referring to Figure 4, a cutaway view of a methane tanker 70 shows a generally prismatic sealed and insulated tank 71 integrated into the vessel's double hull 72. The wall of the tank 71 comprises a primary sealing membrane configured to be in contact with the LNG contained within the tank, a secondary sealing membrane disposed between the primary sealing membrane and the vessel's double hull 72, and two insulating barriers disposed between the primary and secondary sealing membranes and between the secondary sealing membrane and the double hull 72, respectively.

[0073] In a manner known per se, the loading / unloading pipeline 73 located on the upper deck of the ship can be connected by means of suitable connectors to a coastal or port terminal for transferring the cargo of LNG from or to the tank 71.

[0074] 4 also shows an example of a coastal terminal comprising a loading / unloading station 75, a subsea pipe 76, and an onshore facility 77. The loading / unloading station 75 is a fixed offshore facility comprising a movable arm 74 and a tower 78 supporting the movable arm 74. The movable arm 74 supports a bundle of insulated flexible hoses 79 that can be connected to a loading / unloading pipeline 73. The orientable movable arm 74 is suitable for methane tankers of all sizes. A connecting pipe (not shown) extends inside the tower 78. The loading / unloading station 75 allows loading and unloading of the methane tanker 70 from the onshore facility 77 or from the methane tanker 70 to the onshore facility 77. The onshore facility 77 comprises a liquefied gas storage tank 80 and a connecting pipe 81 connected to the loading / unloading station 75 by a subsea pipe 76. The subsea pipe 76 allows liquefied gas to be transported over long distances, such as 5 km, between the loading / unloading station 75 and the onshore facility 77, thereby allowing the methane tanker 70 to be maintained at a long distance from land during loading / unloading operations.

[0075] To generate the pressure required to pump the liquefied gas, pumps on board the ship 70 and / or pumps provided at the land facility 77 and / or pumps provided at the loading / unloading station 75 are used.

[0076] Although the present invention has been described with reference to some particular embodiments, it is to be understood that the invention is in no way limited thereto, but includes all technical equivalents of the described means and combinations thereof insofar as these fall within the scope of the invention as defined in the claims.

[0077] In the claims, any reference signs placed between parentheses shall not be construed as imposing a limitation on the claim.

[0078] Although the present invention has been described with reference to some particular embodiments, it is to be understood that the invention is in no way limited thereto, but includes all technical equivalents of the described means and combinations thereof insofar as these fall within the scope of the invention as defined in the claims.

[0079] Use of the verbs "to have", "to comprise" or "to include" and their conjugations does not exclude the presence of elements or steps other than those stated in a claim.

[0080] In the claims, any reference signs placed between parentheses shall not be construed as imposing a limitation on the claim.

Claims

1. A method for manufacturing an insulating barrier (5) for a wall (1) of a sealed insulated tank fixed to a support structure (2), comprising: directly or indirectly fixing a plurality of insulation panels (11) to the support structure (2) by at least one fixing device (12), the plurality of insulation panels (11) defining an inner surface configured to support a sealing membrane (6) and having a receiving portion (18) opening on the inner surface, the receiving portion (18) receiving the fixing device (12); providing an insulating stopper (25) configured to ensure thermal continuity in the container (18), the insulating stopper (25) having an inner end and an outer end, the insulating stopper (25) having a dimension d1 between the inner end and the outer end, the insulating stopper (25) including an insulating polymer foam layer (23) and an inner rigid sheet (24) secured to the insulating polymer foam layer (23) and forming the inner end of the insulating stopper (25); inserting the insulating stopper (25) into the receiving portion (18) and pushing the insulating stopper (25) toward the support structure (2) until the outer end of the insulating stopper (25) is pressed against a bearing surface spaced from the inner surfaces of the plurality of insulating panels (11) by a distance d2, which is less than d1, toward the support structure (2); and trimming the inner hard sheet (24) of the insulating stopper (25) so that the inner end of the insulating stopper (25) is flush with the inner surface of the plurality of insulating panels (11).

2. 2. The method of claim 1, wherein the inner hard sheet (24) is made of plywood.

3. 3. The method of claim 1 or 2, wherein the inner rigid sheet (24) is glued or stapled to the insulating polymer foam layer (23).

4. The fixing device (12) accommodated inside the accommodation portion (18) has a pin (20) fixed directly or indirectly to the support structure (2); When the plurality of insulation panels (11) are fixed, a retaining member (21) is attached to the pin (20), whereby the retaining member cooperates with at least one retaining zone of the insulation panel (11) to hold the insulation panel (11) towards the support structure (2); The manufacturing method according to any one of claims 1 to 3, wherein a nut (22) is screwed onto the pin (20) to fix the retaining member (21) to the pin (20).

5. 5. The method of claim 4, wherein the retaining member (21) forms the bearing surface against which the outer end of the insulating stopper (25) presses.

6. The insulating stopper (25) has an outer surface that forms the outer end of the insulating stopper (25) and an inner surface that contacts the insulating polymer foam layer (23) of the insulating stopper (25). an outer hard sheet (28) 6. The manufacturing method according to claim 4 or 5, wherein the outer hard sheet (28) has a recess (29) formed in the outer surface of the outer hard sheet (28), in which the nut (22) of the fixing device (12) is accommodated.

7. 7. The method of claim 6, wherein the inner surface of the outer hard sheet (28) at least partially covers the recess (29).

8. The outer hard sheet (28) has a hole (30) that opens into the recess (29) and receives one end of the pin (20), 8. A method according to claim 6 or 7, wherein the hole (30) has a diameter smaller than the diameter of the recess (29).

9. The method of claim 8, wherein the holes (30) are blind holes.

10. A method according to any one of claims 6 to 9, wherein the outer rigid sheet (28) is fixed to the insulating polymer foam layer (23).

11. the outer rigid sheet (28) is free relative to the insulating polymer foam layer (23); 10. The method according to any one of claims 6 to 9, wherein inserting the insulating stopper (25) into the receiving portion (18) comprises a phase of inserting the outer rigid sheet (28) into the receiving portion (18) and a subsequent phase of inserting the insulating polymer foam layer (23) into the receiving portion (18).

12. The insulating polymer foam layer (23) has a density of 100 kg / m ３ to 260 kg / m ３ The method according to any one of claims 1 to 11, wherein

13. A method according to any one of the preceding claims, wherein the inner rigid sheet (24) is stapled to one of the insulating panels (11).

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