Watertight and thermally insulating tank and method for manufacturing such a tank
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- GAZTRANSPORT & TECHNIGAZ SA
- Filing Date
- 2024-08-20
- Publication Date
- 2026-07-10
Abstract
Description
Title of the invention: Watertight and thermally insulating tank and method for manufacturing such a tank. Technical field
[0001] The invention relates to the field of leak-proof tanks with corrugated metal membranes, for the storage and / or transport of a liquefied gas.
[0002] In particular, the invention relates to the field of sealed and thermally insulated tanks for the storage and / or transport of liquefied gases, such as tanks for transporting Liquefied Petroleum Gas (also called LPG) with a temperature, for example, between -50°C and 0°C, or for transporting Liquefied Natural Gas (LNG) at approximately -162°C at atmospheric pressure. These tanks can be installed on land or on a floating structure. In the case of a floating structure, the tank can be used for transporting liquefied gas or for receiving liquefied gas to serve as fuel for the propulsion of the floating structure. Technological background
[0003] In the prior art, it is known that ships have a double hull, that is to say, an inner hull and an outer hull. The inner hull defines a plurality of compartments, each forming a load-bearing structure within which is mounted a sealed and thermally insulated tank for storing a liquefied gas.
[0004] To construct such vessels, it is known to pre-assemble a plurality of vessel sections, each comprising a portion of the outer hull and a portion of the inner hull, and then join the sections together in a dry dock. Subsequently, once the sections have been joined, the walls of the watertight and thermally insulated tanks are mounted and anchored inside the compartments of the inner hull. These tank manufacturing operations are carried out either in a dry dock or at the quayside, after the vessel has been launched, in order to free up the dry dock as quickly as possible. They can also be carried out partly in a dry dock and partly at the quayside. Since all the assembly and anchoring operations for the watertight tank walls are carried out either in a dry dock or at the quayside, such a manufacturing process leads to the monopolization of a dry dock and / or a quay for a significant period of time.However, dry docks and quays are limited in number in shipbuilding yards, which hinders the production capacity of said shipbuilding yards.
[0005] In order to limit the time spent using dry docks, it is known to pre-assemble parts of the ship into sub-assemblies, including elements of the double hull and the tank, and then connect the pre-assembled sub-assemblies to each other. in order to produce sections of a ship incorporating one or more watertight and thermally insulated tanks. Such a manufacturing process is described, for example, in application WO14076424.
[0006] However, prior art methods are not entirely satisfactory, particularly in that they are not suitable for compensating for the positioning tolerances of the tank elements of the various pre-assembled sub-assemblies after said pre-assembled sub-assemblies have been fixed to one another. Summary of the invention
[0007] One idea underlying the invention is to propose a method for manufacturing a sealed and thermally insulating tank which allows, in particular, for reducing the mobilization time of a dry dock and / or a quay.
[0008] Another idea underlying the invention is to propose a method for manufacturing a sealed and thermally insulating tank that is faster, simpler and allows compensation for the relative positioning tolerances of tank elements belonging to several different pre-assembled sub-assemblies.
[0009] According to one embodiment, the invention provides a method for manufacturing a sealed and thermally insulating tank comprising: - provide a first and a second pre-assembled sub-assemblies each comprising: a portion of load-bearing structure, the portion of load-bearing structure of the first and second pre-assembled sub-assemblies comprising respectively a first and a second junction zones; insulating blocks anchored to said portion of the load-bearing structure and equipped with anchoring strips; and a portion of the waterproofing membrane comprising corrugated sheets which are anchored to said anchor strips and welded overlapping to each other; - weld the first and second junction areas together along a first weld line; - anchor at least one insulating joint block at the first and second joint zones between the insulating blocks of the first pre-assembled sub-assembly and the insulating blocks of the second pre-assembled sub-assembly, said insulating joint block spanning the first weld line and comprising a first anchoring strip that is perpendicular to the first weld line and is wider than at least one of the anchoring strips of the insulating blocks of the first and second pre-assembled sub-assemblies; and - anchor corrugated joining sheets to the first anchoring strip and connect them in a watertight manner to the portions of the sealing membrane of the first pre-assembled sub-assembly and the second pre-assembled sub-assembly.
[0010] Thanks to a greater width of the first anchoring strip, the freedom of positioning of the insulating joint block is increased, while maintaining the possibility of welding the edges of the corrugated joint sheets to said first anchoring strip. Such an arrangement thus contributes to compensating for positioning tolerances of the insulating blocks of one pre-assembled sub-assembly to another.
[0011] In addition, such an arrangement of the insulating junction block, straddling the respective junction zones of the first and second pre-assembled sub-assemblies, makes it possible to mitigate the phenomena of stepping or unevenness that may occur between portions of the load-bearing structure belonging to different adjacent pre-assembled sub-assemblies.
[0012] According to embodiments, such a process may include one or more of the following characteristics.
[0013] According to one embodiment, each insulating block comprises a secondary panel, a waterproof coating and a primary panel which are glued to each other, the primary panel having an internal surface in which recesses are provided to house the anchoring strips, the primary panel having dimensions smaller than those of the secondary panel so that a peripheral area of the waterproof coating is not covered by the primary panel, all around it, flexible waterproof strips being positioned straddling the adjacent peripheral areas of the waterproof coatings of the adjacent insulating blocks.
[0014] According to one embodiment, each insulating joint block comprises a secondary panel, a waterproof coating and a primary panel which are glued together, the primary panel having an internal surface in which a recess is provided to house the first anchoring strip, the primary panel having dimensions smaller than those of the secondary panel so that a peripheral area of the waterproof coating is not covered by the primary panel, all around it.
[0015] According to one embodiment, after anchoring the joint insulating block to the first and second joint zones, flexible sealing strips are positioned straddling the peripheral zone of the sealing coating of the joint insulating block and that of at least one insulating block of the first pre-assembled sub-assembly and straddling the peripheral zone of the sealing coating of the joint insulating block and that of at least one insulating block of the second pre-assembled sub-assembly in order to ensure the continuity of the secondary sealing membrane.
[0016] According to one embodiment, the corrugated sheets of the first pre-assembled sub-assembly have first corrugations parallel to each other and perpendicular to the first weld line, and the corrugated sheets of the second sub- pre-assembled assemblies have second corrugations parallel to each other and perpendicular to the first weld line; the corrugated joining sheets having joining corrugations perpendicular to the first weld line, arranged in continuity with the first corrugations; and The corrugated joining sheets are connected to the corrugated sheets of the second pre-assembled sub-assembly by means of a plurality of joining pieces, each comprising: - a first and a second edge, parallel to the first weld line, and respectively welded overlapping with one or more of the joining corrugated sheets and with one or more of the corrugated sheets of the second pre-assembled sub-assembly; - a third and a fourth edge, each connecting the first and second edges; and - undulations extending from the first edge to the second edge, said undulations having a first end portion arranged in continuity with one of the joining undulations and a second end portion arranged in continuity with one of the second undulations and comprising an inclined portion extending in a direction inclined relative to the parallel directions of the first and second undulations; the third edge and the fourth edge of two adjacent joining pieces being welded overlapping each other.
[0017] According to one embodiment, an offset value D is determined representing the offset of the first corrugations with respect to the second corrugations, and the joining pieces are shaped according to said offset value D so that the first and second end portions of each of the corrugations are offset from each other by a distance corresponding to the offset value D.
[0018] According to one embodiment, the first edge has a first notch along which the joining piece is welded to the first anchor strip, said first notch being spaced from the third and fourth edges of the joining piece so as to separate a first portion and a second portion of said first edge which are respectively welded to two adjacent corrugated joining sheets, the second edge having a second notch along which the joining piece is welded to an anchor strip of the second pre-assembled assembly, said second notch being spaced from the third and fourth edges of the joining piece so as to separate a first portion and a second portion of said second edge which are respectively welded to two adjacent corrugated sheets of the second pre-assembled sub-assembly.
[0019] According to one embodiment, the corrugated sheets of the first pre-assembled sub-assembly have first corrugations parallel to each other and perpendicular to the first weld line and the corrugated sheets of the second pre-assembled sub-assembly have second corrugations parallel to each other and perpendicular to the first weld line; in which the corrugated joining sheets anchored to the first anchoring strip comprise a first corrugated joining sheet having joining undulations perpendicular to the first weld line which are arranged in continuity with the first undulations, the first corrugated joining sheet being connected to the corrugated sheets of the first pre-assembled sub-assembly, and a second corrugated joining sheet having joining undulations perpendicular to the first weld line which are arranged in continuity with the second undulations, the second corrugated joining sheet being connected to the corrugated sheets of the second pre-assembled sub-assembly; in which the first joining corrugated sheet is connected to the second joining corrugated sheet by means of at least one joining piece comprising: - a first and a second edge, parallel to the first weld line, and respectively welded overlapping with the first and second joining corrugated sheets; - undulations which extend from the first edge to the second edge, a said undulation comprising a first end portion arranged in continuity with one of the first undulations and a second end portion arranged in continuity with one of the second undulations and an inclined portion which extends in a direction inclined with respect to the first and second undulations.
[0020] According to one embodiment, a third pre-assembled sub-assembly is further provided, comprising: a portion of load-bearing structure; insulating blocks anchored to said portion of the load-bearing structure and equipped with anchoring strips; and a portion of the waterproofing membrane comprising corrugated sheets which are anchored to said anchor strips and welded overlapping to each other; the load-bearing structural portion of the first pre-assembled sub-assembly further comprising a third joining zone, the load-bearing structural portion of the third pre-assembled sub-assembly comprising a fifth joining zone; the manufacturing process further comprising: - weld the third and fifth junction areas together along a second weld line perpendicular to the first weld line; - anchor at least one second insulating joint block at the third and fifth joint zones between the insulating blocks of the first pre-assembled sub-assembly and the insulating blocks of the third pre-assembled sub-assembly, said second insulating joint block spanning the second weld line and comprising a second anchoring strip perpendicular to the second weld line; the second anchoring strip being wider than at least one of the anchoring strips of the insulating blocks of the first and third pre-assembled sub-assemblies; and - anchor the corrugated joining sheets to the second anchoring strip of the second insulating joining block and connect them in a watertight manner to the sealing membrane portions of the first pre-assembled sub-assembly and the third pre-assembled sub-assembly.
[0021] According to one embodiment, a fourth pre-assembled sub-assembly is further provided, comprising: a portion of load-bearing structure; insulating blocks anchored to said portion of the load-bearing structure and equipped with anchoring strips; and a portion of the waterproofing membrane comprising corrugated sheets which are anchored to said anchor strips and welded overlapping to each other; the portion of the load-bearing structure of the second pre-assembled sub-assembly further comprising a fourth joining zone, the portion of the load-bearing structure of the third pre-assembled sub-assembly further comprising a sixth joining zone, and the fourth pre-assembled sub-assembly comprising a seventh and an eighth joining zone; the manufacturing process further comprising: - weld the fourth and seventh junction zones together along a third weld line extending in line with the second weld line; - weld the sixth and eighth junction zones together along a fourth weld line extending in line with the first weld line; - anchor at least one third insulating junction block at the fourth and seventh junction zones between the insulating blocks of the second pre-assembled sub-assembly and the insulating blocks of the fourth pre-assembled sub-assembly, said third insulating junction block spanning the third weld line and comprising a third anchoring strip which is perpendicular to the third weld line and wider than at least one of the anchoring strips of the insulating blocks of the second and fourth pre-assembled sub-assemblies; - anchor at least a fourth insulating junction block to the sixth and eighth junction zones between the insulating blocks of the third pre-assembled sub-assembly and the insulating blocks of the fourth pre-assembled sub-assembly, said fourth insulating junction block spanning the fourth weld line and comprising an anchor strip that is perpendicular to the fourth weld line and wider than at least one of the anchor strips of the insulating blocks of the third and fourth pre-assembled sub-assemblies; and - anchor the corrugated joining sheets to the third anchor strip of the third insulating joining block and connect them airtight to the sealing membrane portions of the second pre-assembled sub-assembly and the fourth pre-assembled sub-assembly; and - anchor corrugated joining sheets to the fourth anchoring strip of the fourth insulating joining block and connect them in a watertight manner to the sealing membrane portions of the third pre-assembled sub-assembly and the fourth pre-assembled sub-assembly.
[0022] According to one embodiment, the load-bearing structural portions of the first and second pre-assembled sub-assemblies comprise a portion of an inner hull and a portion of an outer hull of a ship.
[0023] According to one embodiment, the load-bearing structure portions comprise a network of structural reinforcements including structural reinforcements which are welded, on the one hand, to said portion of the inner shell and, on the other hand, to said portion of the outer shell.
[0024] According to one embodiment, the load-bearing structure portions of each of the first and second pre-assembled sub-assemblies comprise a portion of a cofferdam wall, a portion of a side wall intended to connect two cofferdam walls, a portion of an upper or lower chamfer wall and a portion of a bottom or ceiling wall.
[0025] According to one embodiment, the invention also provides a sealed and thermally insulating tank comprising: - two pre-assembled sub-assemblies, each comprising: a portion of load-bearing structure, the portion of load-bearing structure of the first and second pre-assembled sub-assemblies comprising respectively a first and a second junction zone; insulating blocks anchored to said portion of the load-bearing structure and equipped with anchoring strips; and a portion of the waterproofing membrane comprising corrugated sheets which are anchored to said anchor strips and welded overlapping to each other; the first and second joining zones being welded to each other along a first weld line; - at least one insulating junction block anchored to the first and second junction zones between the insulating blocks of the first pre-assembled sub-assembly and the insulating blocks of the second pre-assembled sub-assembly, said junction insulating block spanning the first weld line and comprising a first anchoring strip perpendicular to the first weld line and which is wider than at least one of the anchoring strips of the insulating blocks of the first and second pre-assembled sub-assemblies; and - corrugated joining sheets which are anchored to the first anchoring strip and are connected in a watertight manner to the portions of the sealing membrane of the first pre-assembled sub-assembly and the second pre-assembled sub-assembly.
[0026] A tank according to one of the aforementioned embodiments may be an onshore storage facility, for example for storing LNG, or be installed in a floating structure, whether coastal or deep-water, including an ethane or LNG carrier, a floating storage and regasification unit (FSRU), a floating production and storage unit (FPSO), and others. In the case of a floating structure, the tank may be intended to receive liquefied natural gas used as fuel for the propulsion of the floating structure.
[0027] According to one embodiment, the invention relates to a vessel for transporting a fluid which includes a tank of the aforementioned type. According to one embodiment, the load-bearing structural portions comprise portions of an inner hull and portions of an outer hull of the vessel.
[0028] According to one embodiment, the invention also provides a transfer system for a fluid, 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 to drive a flow of fluid through the insulated pipes from or to the floating or land-based storage facility to or from the vessel's tank.
[0029] According to one embodiment, the invention also provides a method for loading or unloading such a vessel, in which a fluid is conveyed through insulated pipes from or to a floating or land-based storage facility to or from the vessel's tank. Brief description of the figures
[0030] The invention will be better understood, and other objects, details, features and advantages thereof will become more apparent from the following description of several particular embodiments of the invention, given solely by way of illustration and not limitation, with reference to the accompanying drawings.
[0031] Fig. 1 is a partial representation of a sealed and thermally insulated liquefied gas storage tank, during assembly.
[0032] [Fig. 2] is an enlarged view of area II of [Fig. 1], which illustrates several pre-assembled sub-assemblies intended for the construction of the watertight and thermally insulated tank insulating as well as the junction areas at the interface between said pre-assembled sub-assemblies.
[0033] Fig. 3 is a cross-sectional view of several adjacent insulating blocks.
[0034] Fig. 4 is a view similar to Fig. 2 in which insulating blocks of junctions are arranged in the junction areas.
[0035] Figure 5 is an enlarged view of area V of Figure 4 illustrating in detail one of the insulating blocks placed in the junction areas.
[0036] Figure 6 is similar to Figure 5, which further illustrates corrugated sheets of junction of the primary waterproofing membrane arranged in the junction areas.
[0037] Figure 7 is a view similar to Figure 6, further illustrating connecting pieces of the primary sealing membrane allowing the connection of the corrugated joining sheets to corrugated sheets of one of the pre-assembled sub-assemblies.
[0038] Figure [Fig. 8] is a perspective view of a connecting piece according to a mode of realization.
[0039] Figure 9 is an enlarged view of zone IX of Figure 7 illustrating the membrane primary metallic in an area where connecting pieces join each other and to metal sheets of the primary waterproofing membrane.
[0040] Figure 10 is an enlarged view of area X of Figure 4 illustrating sheets of junction and connecting pieces according to another embodiment.
[0041] Fig. 11 is a plan view of a connecting piece according to another embodiment.
[0042] Figure 12 is viewed similarly to Figure 5, illustrating a junction insulating panel according to another embodiment.
[0043] Fig. 13 is a schematic cutaway representation of a ship's tank LNG carrier and a loading / unloading terminal for this tank. Description of the implementation methods
[0044] By convention, the terms "external" and "internal" are used to define the relative position of one element with respect to another, by reference to the inside and outside of the tank.
[0045] Figure 1 partially illustrates a tank 1 of a ship, intended for storing a liquefied gas, during the assembly of said tank. The liquefied gas intended to be stored in the tank may in particular be liquefied natural gas (LNG) - that is to say a gaseous mixture consisting mainly of methane as well as one or more other hydrocarbons - ethane, liquefied petroleum gas (LPG) - that is to say a mixture of hydrocarbons from petroleum refining consisting mainly of propane and butane - liquid hydrogen or liquid ammonia.
[0046] The tank 1 is supported by a load-bearing structure which, in the illustrated embodiment, is formed by the double hull of a ship. The double hull comprises an outer hull 3 and an inner hull 4.
[0047] The tank 1 is mounted inside a polyhedral compartment of the inner shell 4. The compartment is defined by a plurality of load-bearing walls.
[0048] In the embodiment shown, the compartment is defined by: - two cofferdam walls 11, one of which is shown in [Fig. 1], which extend transversely to the longitudinal direction of the ship; - a ceiling wall 12; - a bottom wall 13; - two lateral walls 14, 15 which extend along the longitudinal direction of the ship and which connect the two walls of cofferdam 11; - two upper chamfered walls 16, 17 which extend along the longitudinal direction of the ship and which each connect, on the one hand, the two cofferdam walls 11 to each other and, on the other hand, one of the side walls 14, 15 to the ceiling wall 12; and - two lower chamfer walls 18, 19 which extend along the longitudinal direction of the vessel and each connect, on the one hand, the two cofferdam walls 11 to each other and, on the other hand, one of the side walls 14, 15 to the bottom wall 13.
[0049] The tank walls have a multilayer structure. Thus, each tank wall comprises successively, from the outside in, along the thickness direction of the wall, a secondary thermally insulating barrier 7 retained to the supporting structure, a secondary sealing membrane 8 bearing against the secondary thermally insulating barrier 7, a primary thermally insulating barrier 9 bearing against the secondary sealing membrane 8 and a primary sealing membrane 10 bearing against the primary thermally insulating barrier 9 and intended to be in contact with the liquefied natural gas contained in the tank.The undulations of the primary membrane are not illustrated in [Fig. 1].
[0050] The construction of the tank 1, as shown in [Fig. 1] and [Fig. 2], includes a preliminary step of manufacturing several pre-assembled sub-assemblies 20, 21, 22, 23. Each pre-assembled sub-assembly 20, 21, 22, 23 comprises a portion of the load-bearing structure, insulating blocks 24 anchored to said portion of the load-bearing structure, portions of the secondary sealing membrane 8 attached to the insulating blocks 24, and, advantageously, corrugated sheets 25 of the primary sealing membrane 10 also anchored to the insulating blocks 24. Preferably, each insulating block 24 forms both a portion of the secondary thermally insulating barrier 7 and a portion of the membrane secondary sealing 8 and a portion of the primary thermally insulating barrier 9.
[0051] In [Fig. 1] and [Fig. 2], four pre-assembled sub-assemblies 20, 21, 22, 23 are shown. Each pre-assembled sub-assembly 20, 21, 22, 23 comprises portions of one or more load-bearing walls of the load-bearing structure. More specifically, in the embodiment shown, each of the pre-assembled sub-assemblies 20 and 21 comprises a portion of the cofferdam wall 11, a portion of one of the side walls 14 and 15, a portion of one of the upper chamfer walls 16 and 17 and a portion of the ceiling wall 12. Each of the pre-assembled sub-assemblies 22 and 23 comprises a portion of the cofferdam wall 11, a portion of one of the side walls 14 and 15, a portion of one of the lower chamfer walls 18 and 19 and a portion of the bottom wall 13.
[0052] Advantageously, each pre-assembled sub-assembly 20, 21, 22, 23 comprises a portion of the inner shell 4, a portion of the outer shell 3 and a network of structural reinforcements including structural reinforcements 76 which are welded, on the one hand, to said portion of the inner shell 4 and, on the other hand, to said portion of the outer shell 3.
[0053] The pre-assembled sub-assemblies 20, 21, 22, 23 are intended to be assembled together to manufacture the tank 1 and, where applicable, a portion of the vessel incorporating it. Advantageously, such pre-assembled sub-assemblies 20, 21, 22, 23 are manufactured in a workshop, thereby minimizing the time required to use a dry dock and / or quay.
[0054] The insulating blocks 24 are fixed to the load-bearing structural portion in a juxtaposed manner according to a repeating pattern. The insulating blocks 24 have longitudinal directions—corresponding to the direction of their longest dimension—which are arranged parallel to each other. As shown in [Fig. 3], each insulating block 24 comprises a secondary panel 2, a waterproof coating 6, and a primary panel 27, which are bonded to one another. The secondary panel 2 comprises an outer rigid plate 28, for example, made of plywood, and a layer of insulating polymer foam 29, for example, fiber-reinforced polyurethane foam, such as glass fibers. The primary panel 27 comprises a layer of insulating polymer foam 38, for example, polyurethane foam advantageously reinforced with fibers, such as glass fibers, and an inner rigid plate 39.
[0055] The waterproof coating 26 covers the secondary panel 2. This waterproof coating 26 comprises, for example, an aluminum sheet sandwiched between two layers of fiberglass fabric impregnated with a resin, for example, of polyamide. The waterproof coating 26 is bonded to the secondary panel 2, for example by means of a polyurethane adhesive.
[0056] The secondary panel 2 and the primary panel 27 have a rectangular parallelepiped shape. The primary panel 27 has smaller dimensions than the secondary panel 2, so that a peripheral area of the waterproof coating 26 is not covered by the primary panel 27, all around it.
[0057] To ensure the fixing of the insulating blocks 24 to the supporting structure, the primary panel 27 has wells 30, regularly distributed along the longitudinal edges of said primary panel 27, and in which anchoring devices 31 are housed. The anchoring devices 31 comprise, for example, a threaded stud which is welded to the portion of the supporting structure and a support plate which is held by a nut, screwed to said stud, against a shoulder provided inside the well 30. Insulating plugs 32 are positioned in the wells 30 in order to fill them.
[0058] To ensure the continuity of the secondary waterproofing membrane 8, flexible waterproofing strips 33 are positioned across the adjacent peripheral areas of the waterproofing coatings 26 of the adjacent insulating blocks 24. The flexible waterproofing strips 33 comprise, for example, an aluminum sheet sandwiched between two layers of resin-impregnated fiberglass fabric.
[0059] Furthermore, in order to ensure the continuity of the primary thermally insulating barrier 9, the space between the primary panels 27 of the adjacent insulating blocks 24 is filled by intermediate primary panels 34. Each intermediate primary panel 34 has a structure similar to that of the primary panels 27, namely a layer of polymer foam 35 and an internal rigid plate 36. The intermediate primary panels 34 are bonded to the waterproof coatings 26.
[0060] As shown, for example, in [Fig. 2], the primary sealing membrane 10 is obtained by assembling a plurality of corrugated sheets 25. Each corrugated sheet 25 has two sets of mutually perpendicular corrugations. The corrugations project towards the interior of the tank. Adjacent corrugated sheets 25 are welded together with an overlap along their edges. In addition, the edges of the corrugated sheets 25 that are overlapped by an edge of an adjacent metal sheet are welded, for example, by spot welding, to anchor strips 37, 82. The anchor strips 37, 82 are housed and fixed in recesses formed in the inner surface of the primary panels 27 and the intermediate primary panels 34, and more particularly in their internal rigid plate 36, 39.In practice, each anchor strip 37 or 82 can be formed from a plurality of metal elements aligned in one direction on the internal rigid plate 39 of a primary panel 27 or an intermediate primary panel 34.
[0061] The corrugated sheets 25 are, for example, made of stainless steel. The corrugated sheets 25 are rectangular and preferably have width and length dimensions that are integer multiples of one inter-corrugation interval of the primary waterproofing membrane 10. Furthermore, the dimensions of the corrugated sheets 25 are also integer multiples of the dimensions of the primary panels 27. Each of the corrugated sheets 25 is anchored astride four adjacent insulating blocks 24. In addition, the corrugated sheets 25 are arranged so that their longitudinal direction, i.e., the direction of their longest dimension, is parallel to the longitudinal direction of the insulating blocks 24. In one embodiment, the corrugated sheets have a length that corresponds to nine inter-corrugation intervals and a width that corresponds to three inter-corrugation intervals.
[0062] The pre-assembled sub-assemblies 20, 21, 22, 23 have, along their edges, joining areas 46, 47, 83, 84, 85, 86, 87, 88 which are intended to be welded to each other by weld lines 41, 42, 89, 90. The joining areas 46, 47, 83, 84, 85, 86, 87, 88 are not covered with insulating blocks 24 until they are welded to each other.
[0063] In the embodiment shown, the tank walls mounted against the cofferdam walls 11, the ceiling wall 12, the bottom wall 13, and the side walls 14, 15 have junction zones 46, 47, 83, 84, 85, 86, 87, 88 perpendicular to each other. The junction zones 46, 47, 83, 84, 85, 86, 87, 88 of said tank walls thus define a cross-shaped pattern. By convention, the junction zones which extend perpendicularly to the longitudinal directions of the insulating blocks 24 of the pre-assembled sub-assemblies 20, 21, 22, 23 shall be designated "transverse junction zones 46, 83, 86, 88" while those which extend parallel to the longitudinal direction of the insulating blocks 24 of the pre-assembled sub-assemblies 20, 21, 22, 23 shall be designated "longitudinal junction zones 47, 84, 85, 87".
[0064] As shown in [Fig. 4], insulating joining blocks 43 are anchored in the joining zones 46, 47, 83, 84, 85, 86, 87, 88 of the pre-assembled sub-assemblies 20, 21, 22, 23. The insulating joining blocks 43 are arranged straddling the joining zones 46, 83; 47, 85; 84, 87; 86, 88 of the two adjacent pre-assembled sub-assemblies 20, 21, 22, 23. In other words, the insulating joining blocks 43 are oriented so that their longitudinal direction, i.e., the direction of their longest dimension, is perpendicular to the weld line 41, 42, 89, 90 which they span. Such an arrangement is advantageous in that it allows to mitigate the phenomena of unevenness, according to the direction of thickness, which may occur between the portions of the load-bearing structure of the adjacent pre-assembled sub-assemblies 20, 21, 22, 23.
[0065] In the intersection zone between the junction zones 46, 47, 83, 84, 85, 86, 87, 88, which are perpendicular to each other, the junction insulating blocks 43 can optionally be positioned perpendicular or parallel to the longitudinal direction of the insulating blocks 24 of the pre-assembled sub-assemblies 20, 21, 22, 23. Advantageously, when the tank wall has a vertical component, as is the case for the cofferdam walls 11 and the side walls 14, 15, the junction insulating blocks 43 are positioned transversely to the direction of the Earth's gravitational field in the intersection zone between the junction zones. This facilitates the placement of the junction insulating blocks 43 in this zone.
[0066] The insulating joint blocks 43 have width and length dimensions that are integer multiples of the spacing between the corrugations of the primary sealing membrane 10. Advantageously, the length of the insulating joint blocks 43 is substantially equal to the sum of the two joint zones 46, 83; 47, 85; 84, 87; 86, 88, respectively located on either side of the weld line 41, 42, 89, 90. In the embodiment shown, the joint zones 46, 83; 47, 85; 84, 87; 86, 88 have equal widths on either side of the weld line 41, 42, 89, 90. Thus, each junction zone 46, 47, 83, 84, 85, 86, 87, 88 corresponds approximately to 50% of the length of the junction insulating blocks 43.
[0067] Advantageously, in the transverse junction zones 46, 83, 86, 88, the width of the junction insulating blocks 43 is equal to the width of the insulating blocks 24. Similarly, in the longitudinal junction zones 47, 84, 85, 87, the width of the junction insulating blocks 43 is such that the length of the insulating blocks 24 is advantageously an integer multiple of the width of the junction insulating blocks 43.
[0068] The insulating joint blocks 43 have a structure similar to that of the insulating blocks 24 described previously. In other words, the insulating joint blocks 43 comprise a secondary panel anchored to the load-bearing structure, a waterproof coating, and a primary panel that are bonded to one another. The primary panels of the insulating joint blocks 43 also include anchoring strips 37, 82, and enlarged anchoring strips 48, 49, which are housed and fixed in recesses formed in the inner surface of said primary panels and to which the edges of the corrugated joint sheets 44, which will be described subsequently, are intended to be welded.
[0069] As with the pre-assembled sub-assemblies 20, 21, 22, 23, flexible sealing strips 33 are positioned straddling the sealing coatings 26 of the adjacent joint insulation blocks 43 and those of the insulation blocks 24 and adjacent joint insulation blocks 43 so as to ensure the sealing of the secondary sealing membrane 8. Similarly, intermediate primary panels 34 are arranged between the primary panels of the adjacent junction insulating blocks 43 and between those of the junction insulating blocks 43 and those of the adjacent insulating blocks 24.
[0070] As shown for example in [Fig.5], the widened anchor strips 48, 49 are oriented perpendicular to the weld line 41, 42, 89, 90 which their insulating joining block 43 spans and have a width greater than the anchor strips 37, 82. The width of the widened anchor strips 48, 49 is, for example, between 9 and 11 cm while that of the anchor strips 37, 82 is between 7 and 9 cm. As seen in Figures 2, 4 and 5, widened anchor strips 48 can also be provided on the insulating blocks 24 of the pre-assembled sub-assemblies 20, 21, 22, 23, at the ends of the anchor strips 37 which are turned towards the weld lines 41, 90. Similarly, widened anchor strips 49 could also be provided on the insulating blocks 24 of the pre-assembled sub-assemblies 20, 21, 22, 23, at the ends of the anchor strips 82 which are turned towards the weld lines 42, 89.
[0071] Thus, by increasing the width of the widened anchor strips 48, 49, the freedom of positioning of the insulating joining blocks 43 is increased, perpendicular to their longitudinal direction while retaining the possibility of welding the edges of the corrugated joining sheets 44 onto said widened anchor strips 48, 49. As will be detailed later, this arrangement helps to compensate for the positioning tolerances of the insulating blocks 24 and the corrugated sheets 25 of a pre-assembled sub-assembly 20, 21, 22, 23 with respect to those of the sub-assembly located on the other side of the weld line 41, 42, 89, 90 in question.
[0072] With reference to Figures 6 and 7, the structure of the primary sealing membrane 10 is observed in the junction zones 46, 47, 83, 84, 85, 86, 87, 88. The primary sealing membrane 10 between the pre-assembled sub-assemblies 20 and 21 will be described in more detail. In the junction zones 46 and 83, the primary sealing membrane 10 comprises corrugated joining sheets 44. In a misalignment compensation zone 40 of the junction zones 46 and 83, an edge of the corrugated joining sheets 44 is connected to the corrugated sheets 25 of the pre-assembled sub-assembly 21 by a joining piece 45. The misalignment compensation zone 40 defines a line that is generally parallel to the weld line 4L. The same applies between each pair of sub-assemblies.
[0073] Preferably, the corrugated joining sheets 44 extend beyond the insulating joining blocks 43 towards the pre-assembled subassembly 21 and reach the primary panels 27 of the pre-assembled subassembly 21. Thus, the edges of the corrugated joining sheets 44 bordering the misalignment compensation zone 40 actually overhang the primary panels 27 of the pre-assembled subassembly 21 and the anchor strips 37 or widened anchor strips 48 carried by these primary panels.
[0074] Thus, [Fig.6] also shows a misalignment compensation zone 51 parallel to the weld line 42, to compensate for misalignments between the pre-assembled sub-assemblies 20 and 22. In the end, the misalignment compensation zones between the four pre-assembled sub-assemblies also define a cross-shaped pattern.
[0075] The connecting pieces 45 have the function of ensuring continuity of the parallel corrugations of two adjacent pre-assembled sub-assemblies 20 and 21 despite the manufacturing tolerances and relative positioning of the pre-assembled sub-assemblies 20 and 21.
[0076] To this end, when the pre-assembled sub-assemblies 20 and 21 have been welded by the weld line 41, an offset value D is determined between the pair of two pre-assembled sub-assemblies 20 and 21 that are welded to each other. The offset value D corresponds, for the pair of two pre-assembled sub-assemblies 20 and 21 welded to each other by the weld line 41, to the minimum distance between the axis of a corrugation perpendicular to said weld line 41 of the pre-assembled sub-assembly 20 (e.g. corrugation 67 of [Fig. 9]) and the axis of a corrugation perpendicular to said weld line 41 of the pre-assembled sub-assembly 21 (e.g. corrugation 68 of [Fig. 9]). As the corrugated sheets 25 are precisely positioned on the insulating blocks 24 of each pre-assembled sub-assembly, the misalignment reflects a corresponding offset between the rows of insulating blocks belonging respectively to the two pre-assembled sub-assemblies 20 and 21.
[0077] To compensate for this misalignment, the insulating junction blocks 43 are arranged straddling the two junction zones 46 and 83 between the pre-assembled sub-assemblies 20 and 21 of the pair. The insulating junction blocks 43 are advantageously positioned so that, in the direction of the weld line 41, they are located at an intermediate position between the rows of insulating blocks of the two pre-assembled sub-assemblies 20 and 21. The insulating junction blocks 43 are, for example, offset in the direction of the weld line 41 by a value P between D / 3 and D, and for example on the order of D / 2, relative to the insulating blocks 24 of one of the two pre-assembled sub-assemblies 20 and 21.
[0078] Furthermore, as shown for example in Figures 8 and 9, the joining pieces 45 have corrugations 52 which each have an inclined portion 69 which extends in a direction inclined relative to the direction of the corrugations perpendicular to the weld line 41, so as to compensate for said offset value D.
[0079] The joining pieces 45 are obtained in one piece from a sheet of metal that has been previously stamped and / or bent. The sheet of metal comprises a series of parallel corrugations 52 and two edge surfaces 53, 54. The two edge surfaces 53, 54 extend along the two longitudinal edges 55, 56 of the metal sheet, i.e., one edge surface corresponds to one lateral end of the joining piece 45. The metal sheet also has a central zone 57 located between the two edge surfaces 53, 54. The edge surfaces 53, 54 are advantageously separated from the central zone 57 by a rib 58 that stiffens the metal sheet. Furthermore, the two edge surfaces 53, 54 form a jogglinage, i.e., they create a slope relative to the central zone 57, enabling them to bridge the edges of the adjacent corrugated sheets 25 and joining corrugated sheets 44.
[0080] Subsequently, this metal sheet is deformed by a machine, designated a "decentering machine". The decentering machine is configured to exert two forces on the metal sheet, directed in opposite directions on either side of a corrugation 52, and whose points of application are offset from each other on either side of a median perpendicular to the corrugation 52 and dividing the metal sheet into two equal portions. These forces are applied until the ends 59, 60 of each of the corrugations 52 are offset from each other by a distance corresponding to the offset value D, previously measured.
[0081] Subsequently, the transverse edges 61, 62 of the metal sheet are cut perpendicularly to the longitudinal edges 55, 56, providing chamfered corner areas 63, 64 between the transverse edges 61, 62 and the longitudinal edges 55, 56. In addition, two notches 65, 66, for example in the shape of an isosceles triangle, are respectively provided in each of the two edge surfaces 53, 54. The notches 65, 66 are provided in areas intended to be positioned opposite the enlarged anchor strips 48, 49. The notches 65, 66 are also offset from each other along the longitudinal direction of the joining piece 45 by a distance corresponding to the aforementioned offset value D.
[0082] In relation to [Fig.9], we observe the connection of the joining pieces 45 between the corrugated joining sheets 44 which extend the undulations of the primary membrane of the pre-assembled sub-assembly 20 and the corrugated sheets 25 of the pre-assembled sub-assembly 21.
[0083] The joining pieces 45 are arranged so that the ends 59 and 60 of each of the corrugations 52 are located respectively opposite one of the corrugations 67 of one of the joining corrugated sheets 44 and one of the corrugations 68 of one of the corrugated sheets 25 of the pre-assembled subassembly 21.
[0084] The longitudinal edge 55 of each joining piece 45 overlaps one of the edges of two adjacent corrugated joining plates 44 while the notch 65 of said longitudinal edge 55 is arranged opposite the anchoring strip 37 of the subassembly pre-assembled 21 (or the extended anchor strip 48 located at the end of the anchor strip 37) at which said corrugated joining sheets 44 terminate. A weld line is made, preferably lap welded, along said longitudinal edge 55 and the notch 65 of the joining piece 45 so as to weld it watertight to the two adjacent corrugated joining sheets 44 as well as to the anchor strip 37 or extended anchor strip 48 of the pre-assembled sub-assembly 21.
[0085] Similarly, the other longitudinal edge 56 of each joining piece 45 overlaps one of the edges of two adjacent corrugated sheets 25, while the notch 66 of said longitudinal edge 56 is positioned opposite the same anchor strip 37 or extended anchor strip 48 at which said corrugated sheets 25 terminate. A weld line is advantageously made in a clinker fashion along said longitudinal edge 56 of the joining piece 45 so as to weld it tightly to the two adjacent corrugated sheets 25 as well as to the anchor strip 37 or extended anchor strip 48 of the pre-assembled subassembly 21.
[0086] In addition, the joining pieces 45 are welded overlapping to each other along their transverse edges 61, 62.
[0087] Such joining pieces 45 are advantageous in that the notches 65, 66, positioned at a distance from the longitudinal edges 55, 56, allow the joining pieces 45 to be welded to each other, on the one hand, and to the anchor strips 37 or extended anchor strips 48, on the other hand, in two different areas. This simplifies the manufacturing operations of the joining pieces 45 and the watertight welding of said joining pieces 45 to each other as well as to the corrugated sheets 25 and the adjacent joining corrugated sheets 44.
[0088] With reference to [Fig. 10], we will describe more precisely the realization of the primary sealing membrane 10 between the pre-assembled sub-assemblies 20 and 22. For this, insulating junction blocks 43 are arranged straddling the junction areas 47 and 85 of the two pre-assembled sub-assemblies 20 and 22 and carry enlarged anchoring strips 49 extending perpendicularly to the weld line 42.
[0089] Corrugated joining sheets 44 straddling the insulating blocks 24 of the pre-assembled sub-assembly 20 and the insulating joining blocks 43 extend the corrugations of the primary membrane of the pre-assembled sub-assembly 20 perpendicular to the weld line 42 to approximately the mid-length of the insulating joining blocks 43. Similarly, corrugated joining sheets 144 straddling the insulating blocks 24 of the pre-assembled sub-assembly 22 and the insulating joining blocks 43 extend the corrugations of the primary membrane of the pre-assembled sub-assembly 22 perpendicular to the weld line 42 to approximately the mid-length of the insulating joining blocks 43. An enlarged anchoring strip 49 is located, in particular, at each zone of overlap between the edges of two junction corrugated sheets 44 and of each overlap zone between the edges of two junction corrugated sheets 144.
[0090] In relation to the corrugated joining sheets 144 of [Fig. 10], it can be seen that a single row of corrugated joining sheets 144 fills the space between the primary membrane of the pre-assembled sub-assembly 22 and the misalignment compensation zone 51. At the same location in the embodiment of [Fig. 7], it can be seen that two rows of joining sheets, not shown, would be required to fill the space between the primary membrane of the pre-assembled sub-assembly 22 and the misalignment compensation zone 51, namely one row extending from the joining sheet 44A and one row extending from the joining sheet 44B.
[0091] The misalignment compensation zone 51 is located between the joining corrugated sheets 144 and the joining corrugated sheets 44. The joining pieces 45 can also be used to connect the joining corrugated sheets 144 to the joining corrugated sheets 44 by compensating for misalignments of the corrugations perpendicular to the weld line 42.
[0092] Alternatively, in the absence of an anchor strip parallel to the misalignment compensation zone 51, modified joining pieces 145 may be used. The modified joining piece 145 is shown in top view in [Fig. 11]. It consists of three sub-parts 146 which are butt-welded parallel to the misalignment compensation zone 51. Each sub-part 146 has a general rectangular shape with chamfered corners. It has a single corrugation 52. As in the joining piece 45, the two edge surfaces 53 and 54 form a joggliding by which the sub-parts 146 are able to overcome the edges of the corrugated joining sheets 44 and 144. In addition, the sub-parts 146 are also welded overlapping to each other along their transverse edges 61 and 62.
[0093] One of the three sub-parts 146 has two notches 65 and 66 located respectively in its two edge surfaces 53 and 54, near the transverse edge 62 which is welded to the enlarged anchoring strip 49. For the rest the modified joining piece 145 is used in the same way as the joining piece 45.
[0094] With reference to [Fig. 12], at the crossing between the misalignment recovery zones 40 and 51, an insulating junction block 143 can carry a rectangular or square metal plate 148, to increase the surface available to join the two rows of junction pieces 45 and to recover from misalignment defects.
[0095] The technique described above for assembling four pre-assembled sub-assemblies 20, 21, 22, 23, whose weld lines 41, 42, 89, 90 form a cross, can easily be adapted to the assembly of only two or three pre-assembled sub-assemblies. In one embodiment, three pre-assembled sub-assemblies feature weld lines joining in the form of a T. For example, this embodiment is obtained from [Fig.2] by merging the pre-assembled sub-assemblies 20 and 21, in which case the joining zones 46 and 83 do not exist and neither does the weld line 41.
[0096] With reference to [Fig. 13], a cutaway view of a ship, here a LNG carrier 70, shows a sealed and thermally insulated tank 71 of generally prismatic shape mounted in the double hull 72 of the ship. The wall of the tank 71 comprises a primary sealed membrane intended to be in contact with the LNG contained in the tank, a secondary sealed membrane arranged between the primary sealed membrane and the double hull 72 of the ship, and two thermally insulating barriers arranged respectively between the primary sealed membrane and the secondary sealed membrane and between the secondary sealed membrane and the double hull 72.
[0097] In a manner known per se, loading / unloading pipelines 73 arranged on the upper deck of the ship can be connected, by means of suitable connectors, to a marine or port terminal to transfer a cargo of LNG from or to the tank 71.
[0098] Figure 13 shows an example of a marine terminal comprising a loading and unloading berth 75, a subsea pipeline 76 and an onshore installation 77. The loading and unloading berth 75 is a fixed offshore installation comprising a movable arm 74 and a tower 78 which supports the movable arm 74. The movable arm 74 carries a bundle of insulated flexible pipes 79 which can be connected to the loading / unloading pipelines 73. The steerable movable arm 74 is adaptable to all LNG carrier sizes. An unshown connecting pipeline extends inside tower 78. The loading and unloading station 75 allows the ship 70 to be loaded and unloaded from or to the onshore facility 77. This facility includes liquefied gas storage tanks 80 and connecting pipelines 81 linked by the subsea pipeline 76 to the loading or unloading station 75.The subsea pipeline 76 allows the transfer of liquefied gas between the loading or unloading station 75 and the onshore installation 77 over a long distance, for example 5 km, which allows the ship 70 to be kept a long distance from the coast during loading and unloading operations.
[0099] To generate the pressure necessary for the transfer of the liquefied gas, pumps on board the ship 70 and / or pumps equipping the land installation 77 and / or pumps equipping the loading and unloading station 75 are used.
[0100] Although the invention has been described in connection with several particular embodiments, it is clearly evident that it is by no means limited to them and that it includes all technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.
[0101] The use of the verb "comprise", "comprendre" or "include" and its conjugated forms does not exclude the presence of other elements or steps than those stated in a claim.
[0102] In the claims, any reference sign in parentheses shall not be interpreted as a limitation of the claim.
Claims
Demands
1. A method for manufacturing a watertight and thermally insulating tank (1,71) comprising: - providing a first and a second pre-assembled sub-assemblies (20, 21) each comprising: a portion of a load-bearing structure, the portion of the load-bearing structure of the first and second pre-assembled sub-assemblies (20, 21) comprising respectively a first and a second junction zone (46, 83); insulating blocks (24) anchored to said portion of the load-bearing structure and equipped with anchoring strips (37, 48, 82); and a portion of a sealing membrane (10) comprising corrugated sheets (25) which are anchored to said anchoring strips (37, 48, 82) and welded overlapping to each other; - welding the first and second junction zones (46, 83) to each other along a first weld line (41);- anchor at least one insulating joint block (43) to the first and second joint zones (46, 83) between the insulating blocks of the first pre-assembled sub-assembly (20) and the insulating blocks of the second pre-assembled sub-assembly (21), said insulating joint block (43) spanning the first weld line (41) and comprising a first anchoring strip (48) which is perpendicular to the first weld line (41) and is wider than at least one of the anchoring strips of the insulating blocks of the first and second pre-assembled sub-assemblies (20, 21); and - anchor corrugated joint sheets (44) to the first anchoring strip (48) and connect them in a watertight manner to the portions of the sealing membrane (10) of the first pre-assembled sub-assembly (20) and the second pre-assembled sub-assembly (21).
2. A manufacturing method according to claim 1, wherein the corrugated sheets of the first pre-assembled sub-assembly (20) have first corrugations parallel to each other and perpendicular to the first weld line (41) and the corrugated sheets of the second pre-assembled sub-assembly (21) have second corrugations parallel to each other and perpendicular to the first weld line (41); in which the joining corrugated sheets (44) have joining corrugations perpendicular to the first weld line (41) which are arranged in continuity with the first corrugations; and in which the joining corrugated sheets (44) are connected to the corrugated sheets of the second pre-assembled sub-assembly (21) by means of a plurality of joining pieces (45) each comprising: - a first and a second edge (55, 56), parallel to the first weld line (41), and respectively welded in overlap with one or more of the joining corrugated sheets (44) and with one or more of the corrugated sheets of the second pre-assembled sub-assembly (21); - a third and a fourth edge (61, 62) which each connect the first and the second edge (55, 56);and - undulations (52) extending from the first edge (55) to the second edge (56), said undulations (52) having a first end portion (59) arranged in continuity with one of the joining undulations and a second end portion (60) arranged in continuity with one of the second undulations and comprising an inclined portion (69) extending in a direction inclined with respect to the parallel directions of the first and second undulations; and wherein the third edge (61) and the fourth edge (62) of two adjacent joining pieces (45) are welded overlapping to each other.
3. A manufacturing method according to claim 2, wherein the first edge (55) has a first notch (65) along which the joining piece (45) is welded to the first anchor strip (48), said first notch (65) being spaced from the third and fourth edges (61, 62) of the joining piece (45) so as to separate a first portion and a second portion of said first edge (55) which are respectively welded to two adjacent corrugated joining plates (44), the second edge (56) having a second notch (66) along which the joining piece (45) is welded to an anchor strip (37) of the second pre-assembled assembly, said second notch (66) being spaced from the third and fourth edges (61, 62) of the joining piece (45) so as to separate a first
4.
5. portion and a second portion of said second edge (56) which are respectively welded to two adjacent corrugated sheets (25) of the second pre-assembled sub-assembly (21). Manufacturing method according to claim 1, wherein the corrugated sheets of the first pre-assembled sub-assembly (20) have first corrugations parallel to each other and perpendicular to the first weld line (42) and the corrugated sheets of the second pre-assembled sub-assembly (22) have second corrugations parallel to each other and perpendicular to the first weld line (42); in which the joining corrugated sheets (44) anchored to the first anchoring strip (49) comprise a first joining corrugated sheet (44) having joining undulations perpendicular to the first weld line (42) which are arranged in continuity with the first undulations, the first joining corrugated sheet (44) being connected to the corrugated sheets of the first pre-assembled sub-assembly (20), and a second joining corrugated sheet (44) having joining undulations perpendicular to the first weld line (42) which are arranged in continuity with the second undulations, the second joining corrugated sheet (44) being connected to the corrugated sheets of the second pre-assembled sub-assembly (22); in which the first corrugated joining sheet (44) is connected to the second corrugated joining sheet (44) by means of at least one joining piece (45) comprising: - a first and a second edge (55, 56), parallel to the first weld line (42), and respectively welded overlapping with the first and second corrugated joining sheets (44); - undulations (52) extending from the first edge (55) to the second edge (56), a said undulation (52) comprising a first end portion (59) arranged in continuity with one of the first undulations and a second end portion (60) arranged in continuity with one of the second undulations and an inclined portion (69) extending in a direction inclined with respect to the first and second undulations. A manufacturing method according to any one of claims 1 to 3, wherein a third pre-assembled sub-assembly (22) is provided, comprising: a portion of load-bearing structure; insulating blocks anchored to said portion of load-bearing structure and equipped with anchoring strips; and a portion of waterproofing membrane comprising corrugated sheets which are anchored to said anchoring strips and welded overlapping to each other; the portion of load-bearing structure of the first pre-assembled sub-assembly (20) further comprising a third joining zone (47), the portion of load-bearing structure of the third pre-assembled sub-assembly (22) comprising a fifth joining zone (85); the manufacturing process further comprising: - welding the third and fifth joining zones (47, 85) to each other along a second weld line (42) perpendicular to the first weld line (41);- anchor at least one second insulating joint block at the third and fifth joint zones (47, 85) between the insulating blocks of the first pre-assembled sub-assembly (20) and the insulating blocks of the third pre-assembled sub-assembly (22), said second insulating joint block (43) spanning the second weld line (42) and comprising a second anchoring strip (49) perpendicular to the second weld line (42); the second anchoring strip (49) being wider than at least one of the anchoring strips of the insulating blocks of the first and third pre-assembled sub-assemblies (20, 22); - anchor corrugated joint sheets (44) to the second anchoring strip (49) of the second insulating joint block and connect them in a watertight manner to the portions of the sealing membrane of the first pre-assembled sub-assembly (20) and the third pre-assembled sub-assembly (22).
6. A manufacturing method according to claim 5, wherein a fourth pre-assembled sub-assemblies (23) are provided comprising: a portion of a load-bearing structure; insulating blocks anchored to said portion of a load-bearing structure and equipped with anchoring strips; and a portion of a sealing membrane comprising corrugated sheets which are anchored to said anchoring strips and welded overlapping to each other; the portion of the load-bearing structure of the second pre-assembled sub-assembly (21) further comprising a fourth joining zone (84), the portion of the load-bearing structure of the third pre-assembled sub-assembly (22) further comprising a sixth joining zone (86), and the fourth pre-assembled sub-assembly (23) comprising a seventh and an eighth joining zone (87, 88); the manufacturing process further comprising: - weld the fourth and seventh junction zones (84, 87) to each other along a third weld line (89) extending in line with the second weld line (42); - weld the sixth and eighth junction zones (86, 88) to each other along a fourth weld line (90) extending in line with the first weld line (41); - anchor at least one third insulating junction block at the fourth and seventh junction zones (84, 87) between the insulating blocks of the second pre-assembled sub-assembly (21) and the insulating blocks of the fourth pre-assembled sub-assembly (23), said third insulating junction block (43) spanning the third weld line (89) and comprising a third anchoring strip (49) which is perpendicular to the third weld line (89) and wider than at least one of the anchoring strips of the insulating blocks of the second and fourth pre-assembled sub-assemblies (21, 23); - anchor at least one fourth insulating junction block at the sixth and eighth junction zones (86, 88) between the insulating blocks of the third pre-assembled sub-assembly (22) and the insulating blocks of the fourth pre-assembled sub-assembly (23), said fourth insulating junction block (43) spanning the fourth weld line (90) and comprising an anchoring strip (48) that is perpendicular to the fourth weld line (90) and wider than at least one of the anchoring strips of the insulating blocks of the third and fourth pre-assembled sub-assemblies (22, 23); and - anchoring corrugated joining sheets (44) to the third anchoring strip (49) of the third insulating joining block (43) and connecting them in a watertight manner to the sealing membrane portions of the second pre-assembled sub-assembly (21) and the fourth pre-assembled sub-assembly (23); and - anchor the corrugated joining sheets (44) to the fourth anchoring strip (48) of the fourth insulating joining block (43) and the connect in a watertight manner to the portions of the sealing membrane of the third pre-assembled sub-assembly (22) and of the fourth pre-assembled sub-assembly (23).
7. A manufacturing method according to any one of claims 1 to 6, wherein the load-bearing structural portions of the first and second pre-assembled sub-assemblies (20, 21) comprise a portion of an inner hull (4) and a portion of an outer hull (3) of a ship.
8. A watertight and thermally insulating tank (1,71) comprising: - two pre-assembled sub-assemblies each comprising: a portion of a load-bearing structure, the portion of the load-bearing structure of the first and second pre-assembled sub-assemblies (20, 21) comprising respectively a first and a second junction zone; insulating blocks anchored to said portion of the load-bearing structure and equipped with anchoring strips; and a portion of a sealing membrane comprising corrugated sheets which are anchored to said anchoring strips and welded overlapping to each other; the first and second junction zones being welded to each other along a first weld line (41);- at least one insulating joint block (43) anchored to the first and second joint zones between the insulating blocks of the first pre-assembled sub-assembly (20) and the insulating blocks of the second pre-assembled sub-assembly (21), said insulating joint block (43) spanning the first weld line (41) and comprising a first anchoring strip (48) perpendicular to the first weld line (41) and which is wider than at least one of the anchoring strips of the insulating blocks of the first and second pre-assembled sub-assemblies (20, 21); and - corrugated joint sheets (44) which are anchored to the first anchoring strip (48) and are hermetically connected to the portions of the sealing membrane of the first pre-assembled sub-assembly (20) and the second pre-assembled sub-assembly (21).
9. Vessel (70) for the transport of a fluid, the vessel comprising a tank (1, 71) according to claim 8, wherein the portions of the load-bearing structure comprise portions of an inner hull (4) and portions of an outer hull (3) of the vessel.
10. Transfer system for a fluid, the system comprising a vessel (70) according to claim 9, insulated pipes (73, 79, 76, 81) arranged to connect the vessel's tank (1, 71) to a floating or land-based storage facility (77) and a pump for conveying a fluid through the insulated pipes from or to the floating or land-based storage facility to or from the vessel's tank.
11. A method of loading or unloading a ship (70) according to claim 9, wherein a fluid is conveyed through insulated pipes (73, 79, 76, 81) from or to a floating or land-based storage facility (77) to or from the ship's tank (1, 71).