WO2014076424A1

WO2014076424A1 - Method for the manufacture of a sealed and thermally insulated tank wall

Info

Publication number: WO2014076424A1
Application number: PCT/FR2013/052737
Authority: WO
Inventors: Pierre Jean; Bruno Guelton
Original assignee: Gaztransport Et Technigaz
Priority date: 2012-11-16
Filing date: 2013-11-14
Publication date: 2014-05-22
Also published as: KR20150086304A; JP6351610B2; KR101966963B1; CN104853983B; CN104853983A; FR2998256B1; MY192316A; JP2016503368A; FR2998256A1

Abstract

Method for manufacturing a sealed and thermally insulated tank wall comprising the steps of: - anchoring a thermally insulating barrier subassembly (16) on a bearing wall (1); - placing a sealed covering to cover said insulating barrier subassembly, the placement of the sealed covering involving a step of positioning a sealing barrier element (15) on the insulating barrier subassembly (16) and covering said insulating barrier subassembly (16), the sealing barrier element (15) being parallel to the bearing wall, and a step of placing lateral partitioning elements (20, 19, 17) around the insulating barrier subassembly (16) sealingly connecting the sealing barrier element (15) to the bearing wall (1) so as to form a closed volume (32) between the sealing barrier element and the bearing wall (1); - checking the fluid tightness of said closed volume (32).

Description

Process for producing a sealed and thermally insulated tank wall

The invention relates to the field of manufacturing sealed and thermally insulating vessels. In particular, the present invention relates to tanks for the storage or transport of cold or hot liquids, for example tanks for the storage and / or transport of liquefied gas by sea.

Such sealed and thermally insulating vessels can be used in the field of energy, in particular for storing liquefied natural gas (LNG) at atmospheric pressure at about -163 ° C. in tanks embedded in floating structures.

For example, the document FR2798358 describes a storage tank integrated in the hull of a ship, the walls of which comprise successively, in the direction of the thickness from the inside to the outside of the tank, a primary watertight barrier, a primary insulating barrier, a secondary watertight barrier and a secondary insulating barrier. The insulating barriers consist of juxtaposed heat insulating elements comprising a heat insulating lining.

It is also known from document FR2780767 a wall for a cryogenic tank.

According to one embodiment, the invention provides a method of manufacturing a sealed and thermally insulated tank wall comprising the steps of:

- anchoring a subset of thermally insulating barrier on a bearing wall of the vessel;

putting in place a waterproof coating covering said insulating barrier subassembly, the implementation of the waterproofing coating comprising a step of positioning a watertight barrier element on the insulating barrier subassembly and covering said barrier subassembly; insulating, the sealed barrier element being parallel to the the supporting wall, and

a step of placing lateral partition elements around the insulating barrier subassembly sealingly connecting the sealing barrier element to the supporting wall, so as to form a closed volume between the watertight barrier element and the supporting wall;

- check the tightness of said closed volume.

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

According to embodiments, the method further comprises the steps of:

- Juxtapose a second subset of insulating barrier relative to the first closed volume on the carrier wall;

setting up a second sealing barrier element on the second insulating barrier subassembly, the second sealing barrier element being parallel to the supporting wall and covering said second insulating barrier subassembly,

bonding the second sealed barrier element to the lateral partitioning elements of the first watertight coating so as to form a second closed volume adjacent to the first closed volume and separated from the first closed volume by the lateral partitioning elements;

putting in fluidic communication the first closed volume with the second closed volume.

According to embodiments, the method further comprises a step of checking the tightness of the second closed volume prior to the step of producing the opening.

According to embodiments, the verification of the tightness of the second closed volume is performed through an orifice made in the second sealing barrier element and wherein the opening is made by drilling through said orifice. According to embodiments, the fluidic communication of the first closed volume with the second closed volume comprises the step of making an opening in a lateral partitioning element between the first sealed volume and the second sealed volume.

According to embodiments, the step of producing an opening comprises a step of drilling the lateral partitioning element through the second sealing barrier element and through the second subassembly of insulating barrier.

According to embodiments, the opening is made in a projecting and hollow part of the partitioning element, the projecting piece extending in a direction opposite to the first subassembly of insulating barrier and opening into said first volume. closed.

According to embodiments, the step of placing in fluid communication the first closed volume with the second closed volume comprises the step of setting up a fluid circuit disposed outside the bearing wall and comprising a first pipe of connection opening through the carrier wall to communicate with the first closed volume and a second connecting pipe opening through the carrier wall to communicate with the second closed volume.

According to embodiments, the step of placing in fluid communication further comprises the steps of:

- Make a drilling of the bearing wall to the right of each of the closed volumes;

- Set up in each of the holes the respective connecting pipe to connect each of the closed volumes to the fluid circuit disposed outside the carrier wall.

According to embodiments, the step of placing lateral partitioning elements comprises a step of sealingly connecting a plate of the partitioning elements. lateral to the carrier wall and the first subset of the sealed barrier, the plate extending perpendicularly to the carrier wall.

According to embodiments, the step of placing lateral partitioning elements comprises a step of fixing an edge plate on the first thermally insulating barrier sub-assembly, said edge plate forming a bank of the coating. waterproof,

the first watertight barrier element being sealingly connected to the edge plate during the installation of lateral partition elements

the second watertight barrier element being sealingly connected to the edge plate when connecting the second watertight barrier element to the lateral partition elements.

The connection between the edge plate and the watertight barrier elements is achieved by welding, bonding, bolting or otherwise.

According to embodiments, the method further comprises, after the step of verifying the tightness of said closed volume, the steps of:

- Have a subset of primary insulating barrier on the first sealed barrier element;

- put in place a primary waterproof coating covering said subassembly of primary insulating barrier, the establishment of the primary waterproof coating comprising

a step of positioning a primary waterproof barrier element on the primary insulating barrier subassembly and covering said primary insulating barrier subassembly, the primary barrier element being parallel to the carrier wall, and

a step of placing primary lateral partition elements around the primary insulating barrier subassembly sealingly connecting the primary watertight barrier element to the first watertight coating, so as to form a primary closed volume between the primary barrier element and the first metal coating;

- check the tightness of said primary closed volume.

According to embodiments, the method further comprises the steps of:

- juxtaposing a second subset of primary insulating barrier with respect to the first primary closed volume;

putting in place a second primary watertight barrier element on the second primary insulating barrier subassembly, the second primary waterproofing barrier element being parallel to the supporting wall and covering said second primary insulating barrier subassembly,

bonding the second primary watertight barrier element to the primary lateral partitioning elements of the first watertight primary coating so as to form a second primary closed volume adjacent to the first primary closed volume and separated from the first primary closed volume by the primary lateral partitioning elements;

- Make an opening in a primary lateral partition element between the first primary closed volume and the second primary closed volume.

According to embodiments, the method further comprises a step of checking the tightness of the second primary closed volume prior to the step of producing the opening in the primary lateral partition element.

According to embodiments, the verification of the tightness of a closed volume includes a step of injecting detectable gas into said closed volume so as to generate an overpressure in said closed volume and a step of detecting the test gas. detectable outside said closed volume.

According to embodiments, the test gas injected into said closed volume during the verification of the seal is helium or ammonia. According to embodiments, the method further includes a step of releasably securing the side partition members to the sealed barrier member and the carrier wall.

According to embodiments, the vessel carrying wall includes a first pan and a second pan defining an angle, the thermally insulating barrier subassembly comprising a first thermally insulating barrier unit and a second thermally insulating barrier unit.

wherein the step of anchoring the thermally insulating barrier subassembly on a carrier wall comprises:

- An anchoring step of the first thermally insulating barrier unit on the first panel of the carrier wall;

- A step of anchoring the second thermally insulating barrier unit on the second side of the carrier wall;

and wherein the sealed barrier element is positioned on the insulating barrier subassembly so as to cover the first thermally insulating barrier unit and the second thermally insulating barrier unit;

- A step of fixing the sealed barrier with a coupler fixed to an anchor plate secured to the first panel and the second panel of the wall, the plate being disposed at an intersection between the first panel and the second panel, the coupler comprising a rod oriented from the plate on a bisector of the angle defined by the two panels, the coupler further comprising a sleeve sealingly traversing the waterproof coating and ensuring attachment of the sealed liner to the rod.

According to one embodiment, a sealed and thermally insulated tank wall comprises:

a supporting wall

a thermally insulating barrier subassembly disposed on the carrier wall of the vessel;

a waterproof coating covering said insulating barrier subassembly, the waterproof coating comprising

a sealed barrier element disposed on the insulating barrier subassembly and covering said insulating barrier subassembly, the sealed barrier element being parallel to the carrier wall,

lateral partitioning elements around the insulating barrier subassembly sealingly connecting the sealed barrier element to the supporting wall, so as to form a first closed space between the sealing barrier element and the supporting wall;

a second subset of insulating barrier arranged juxtaposed with respect to the first closed volume on the carrier wall; a second sealing barrier element on the second insulating barrier subassembly the second sealing barrier element being parallel to the supporting wall and covering said second insulating barrier subassembly, the second sealing barrier element being connected to the lateral partitioning elements the first watertight coating to form a second closed volume adjacent to the first closed volume and separated from the first closed volume by the lateral partitioning elements; and

a fluid communication means putting the first closed volume in fluid communication with the second closed volume.

A tank formed from such tank walls can be part of an onshore storage facility, for example to store LNG or be installed in a floating structure, coastal or deep water, including a LNG carrier, a floating unit of Storage and Regasification (FSRU), a floating production and remote storage unit (FPSO) and others.

According to one embodiment, a vessel for the transport of a cold liquid product comprises a double hull and a aforementioned tank disposed in the double hull. According to one embodiment, the invention also provides a method of loading or unloading such a vessel, in which a cold liquid product is conveyed through isolated pipes from or to a floating or land storage facility to or from the vessel vessel.

According to one embodiment, the invention also provides a transfer system for a cold liquid product, the system comprising the abovementioned vessel, insulated pipes arranged to connect the vessel installed in the hull of the vessel to a floating storage facility. or terrestrial and a pump for driving a flow of cold liquid product through the insulated pipelines from or to the floating or land storage facility to or from the vessel vessel.

According to one embodiment, the invention also provides an automatic rail welding device from a first metal part to a second metal part, the two metal parts being arranged to be assembled by a linear weld, the weld having a parallel direction. to the rail, the device comprising:

a guide rail having a tread,

a carriage held to the guide rail by a wheel, the wheel being adapted to cooperate with the tread of said rail for driving the carriage on the rail in an advance parallel to the direction of the rail,

the carriage comprising a welding torch, the welding torch being capable of producing a weld parallel to the direction of the rail between the two metal parts,

the carriage further comprising a pressure arm oriented parallel to the welding torch, the arm being adapted to apply a pressing force of the first metal part on the second metal part. According to one embodiment, the pressure arm comprises at one end in contact with the first metal part a plating roller adapted to press the first metal part on the second metal part. According to one embodiment, the pressure arm further comprises means for adjusting the length of the arm adapted to lengthen and retract the arm.

According to one embodiment, the roller is arranged to maintain a gap between the first metal part and the welding torch.

According to one embodiment, the pressure arm is articulated around an axis parallel to the direction of the rail.

According to one embodiment, the guide rail further comprises a rack and the carriage further comprises a second wheel, the second wheel having a toothing adapted to cooperate with the rack of the rail to cause the movements of the carriage on the rail.

According to one embodiment, the carriage is suspended by the wheel from the guide rail.

An idea underlying the invention is to provide a sealed and thermally insulating tank made in a modular manner from a plurality of tank wall subassemblies whose sealing is independently validated each time, in performing a subset using a sealed membrane portion sealingly connected to the carrier structure, to form a closed volume.

Some aspects of the invention start from the idea of allowing both a complete seal of a subset of the tank wall before the assembly of several subassemblies together, while allowing the communication of the insulating barrier. different subsets after assembling these subsets together.

Some aspects of the invention are based on the idea of connecting subsystems of the tank wall with connecting sealing barrier elements and checking the sealing of the connection independently of the seal. said subsets.

The invention will be better understood, and other objects, details, features and advantages thereof will become more clearly apparent in the art. During the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting, with reference to the accompanying drawings.

On these drawings:

FIG. 1 is a diagrammatic cross-sectional view of a vessel of a methane tanker made by an assembly of pre-armed blocks of subassemblies of a tank wall, the tank wall sub-assemblies being connected by elements connections.

• Figures 2 and 3 show in section the edge of a secondary sealed and thermally insulating barrier of a tank wall subassembly, when assembled on a block.

FIGS. 4 and 5 show in section the edge of the vessel wall subassembly during the assembly of a primary waterproof and thermally insulating barrier on the secondary waterproof and thermally insulating barrier of FIG.

• Figure 6 illustrates the connection zone of two pre-armed blocks of a LNG tank.

• Figure 7 is an enlarged view of the zone VII of Figure 6 coated with a box arranged to make up a flatness.

FIG. 8 illustrates the edge of the subassembly of FIG. 5 when it is connected with secondary sealed and thermally insulated barrier members.

FIGS. 9 and 10 illustrate the edge of the subassembly shown in FIG. 8 when it is connected with primary sealed and thermally insulating barrier elements.

• Figure 1 1 is a schematic cutaway representation of a vessel tank LNG and a loading / unloading terminal of this vessel.

• Figure 12 is a schematic sectional view of a vessel of a LNG tank made by an assembly of pre-armed blocks of tank wall subassemblies, equipped with a collector fluid circuit. • Figure 13 illustrates a corner area of the vessel with connections to the fluid circuit.

• Figure 14 shows in section the edge of a secondary sealed and thermally insulating barrier of a subassembly of the tank wall, when assembled on a block.

FIG. 15 illustrates a pre-armed block comprising a coupler arranged in the angle of a dihedron of the pre-armed block.

Figure 1 illustrates a sectional view of a vessel vessel for storing a cold fluid such as liquefied natural gas (LNG). Such a tank has walls anchored to a carrying structure of the ship. In particular, the carrier structure here consists of the inner hull of a double-hulled vessel, the wall of the inner hull being represented by the number 1.

On each wall of the supporting structure, a corresponding wall of the vessel is made by superposing, successively, a secondary insulation layer 2, a secondary watertight barrier 3, a primary insulation layer 4 and a primary watertight barrier 5. The anchoring of the heat-insulating elements of the secondary insulation layer on the wall of the supporting structure is achieved for example by cooperation between studs and lower edges of the heat-insulating elements, by cooperation of a coupler with heat-insulating elements, by gluing. or any other suitable means.

The primary insulation layer 4 and the secondary insulation layer 2 consist of heat insulating elements juxtaposed in a regular pattern, in particular, the heat-insulating elements are substantially parallelepiped shaped boxes. The primary heat-insulating elements and the secondary heat-insulating elements thus form an insulating layer having a substantially flat surface which carries respectively the primary watertight barrier 5 and the secondary watertight barrier 3.

The manufacture of the ship's structure and in particular the double hull of the ship is achieved by assembling prefabricated blocks 6 of big size. The prefabricated blocks 6 may in particular already comprise a part of the piping and equipment. For example, in FIG. 1, the carrier structure in cross-section of the vessel was made using four prefabricated blocks 6. More precisely, the vessel has a section having upper chamfers 60 and lower chamfers 61. A double deck block 7 and a double bottom block 8 are joined at ends 9 to two side blocks 10. The ends of the double deck block 7 are located at half of the upper chamfers 60. The ends of the block of double bottom 8 are located at half of the lower chamfers 61. The cofferdams, corresponding to the elements of the supporting structure separating two adjacent tanks in a ship, also consist of a prefabricated block connected to the periphery formed by the double deck blocks 7, the double bottom blocks 8 and the lateral blocks 10 shown in Figure 1. Each prefabricated block 6 consists of several sub-blocks 1 1 assembled to form each of the prefabricated blocks 6.

Before assembling the prefabricated blocks 6 together, part of the tank walls may be pre-armed on the blocks 6. For this purpose, subsets 12 of the tank wall are mounted on the inner wall 1 of the block 6 before assembling the blocks 6 between them in dry dock to form the ship. The pre-assembly of the tank wall subassemblies 12 on blocks makes it easier to manufacture the insulation and the watertight barriers by making it possible to work on flat and quay areas, for example in the workshop. Furthermore, pre-arming blocks 6 reduces the amount of scaffolding needed in the tank during assembly of the sealed tank and thermally insulating.

However, the tank wall sub-assemblies do not extend to the ends 9 of the blocks 6 so as to allow the assembly, in particular the welding, of the blocks 6 between them during a step of assembly in the hold dried. Connection areas 13 of about one meter wide on the inner shell 1 are not covered with layers of insulation and sealed barrier before assembling the blocks 6 between them. Thus, after assembling the blocks, the impervious barriers and the insulation layers of sub-assemblies 12 of adjacent prefabricated blocks 6 are connected by means of heat-insulated connection elements placed between the adjacent subassemblies 12. and by the establishment of sealing barrier connection elements 14 welded tightly to the impervious barriers 3 and 5 of the adjacent subsets 12. Thus, the pre-arming of the blocks by subassemblies of the tank wall also makes it possible to reduce the time of occupation of the dry dock or the loading docks for the realization of the tank walls because at this stage only the zones of connection need to be put in place.

During the pre-assembly of a subassembly 12 on a block 6, the secondary sealed barrier 3 of the subassembly is mounted so as to form a sealed volume with the supporting structure 1, then the tightness of the sealed volume is tested. The primary barrier 5 is then mounted to form a second sealed volume which is subsequently tested. In this way, the sealing of the tank wall subassembly 12 of each block can be validated prior to assembling the blocks 6. Thus, the blocks are independently tested, which makes it possible to carry out the validation of the watertightness in an efficient and economical way in test time, while limiting the risks of presence of loss of tightness during the implementation of the tank. Furthermore, it is possible to validate the tightness of each sealed barrier 3 and 5 belonging to a subassembly 12 independently without the need to dismantle the primary barrier element 5 in the event of detection of leakage in the secondary sealed barrier 3 .

Subsequently, the connection of the sub-assemblies 12 can be achieved by means of a connection membrane. The verification of the seal can therefore be performed above the connection zones 13 mainly because the subsets 12 have been previously validated.

However, in order to allow the circulation of inert gas within the primary and secondary insulation layers, openings are made between the sealed volumes of the primary insulating layers of the blocks. adjacent and between the volumes of the secondary insulating layers of the adjacent blocks.

FIGS. 2 to 10 illustrate steps of the method of producing a subset 12 of the tank wall located in the zone II-II of FIG. 1 followed by the steps of linking the subassembly 12 to an adjacent subassembly 12 via connecting elements.

As can be seen in FIG. 10, the primary watertight barrier 5 and the secondary watertight barrier 3 of FIG. 1 are present in the form of metal membranes consisting of raised invar® parallel strakes, which are arranged alternately with elongated welding supports, also in invar®. More specifically, the welding supports project on the insulation layer 2 or 4 perpendicularly to the wall and are retained each time to the underlying insulation layer 2 or 4. For example, the weld supports are housed in inverted T-shaped grooves formed in heat-insulated box liner panels of the insulation layers 2 or 4. The raised edges 18 of the strands 15 are welded along the welds. A sealed barrier comprising strakes with raised edges of this type is described in particular in the document FR2798358.

The steps of making and verifying the tightness of the primary watertight barrier 5 and the secondary watertight barrier 3 of a subassembly 12 during the pre-cocking of a block 6 of the ship's structure are illustrated in FIGS. Figures 2 to 5.

Indeed, Figure 2 shows the edge of the subassembly 12 during assembly of the secondary sealed barrier 3 on the secondary insulation layer 2. For this purpose, a set of boxes 16 corresponding to the subassembly 1 2 is fixed on the carrier wall 1 of the block 8, each of the boxes having a plywood lid panel (not shown). Edge plates 17 in invar® of 1 mm are fixed by screwing on the cover panels of the edge box 1 6 so as to protruding on the edges of the subassembly 12, thus forming a bank. The invar® strakes 15 are then disposed between the weld supports, and the raised edges 18 of the strakes 15 are welded to the weld supports. The invar® strakes 15 are then anchored by welding to the edge plates 1 7. Steel angles 19 and secondary partition plates 20 made of 0.7 mm invar® are placed under the bank of the subassembly 12. perpendicular to the supporting wall 1. The partition plates 20 have a flange 21 extending parallel to the secondary watertight barrier 3 and under it.

A knurling-welding device 22 makes it possible to seal the secondary partition plates 20 to the watertight barrier 3. As can be seen in FIG. 2, the welding device 22 comprises a rail 23 mounted at the height of the bank on a frame 24. The frame 24 is anchored to the carrier wall 1 by means of telescopic legs 25 having magnetic pads 26 bearing on the carrier wall 1. A roller welder can move along the rail 23 by means of wheels 27 resting on the edges of the rail 23. The rail 23 comprises on one side a rack toothing cooperating with one of the wheels 27. This wheel 27 is serrated and allows the drive of the carriage along the rail by gear on the rack. The roller welder 41 has a substantially U-shaped body 28 within which extends a shore plate 1 7. A wheel 29 is positioned at each end of the U, the two wheels 29 being thus superimposed and separated by the shore of the watertight barrier 3 and the wing 21 of a secondary partition plate 20. The two knobs 29 are electrodes that allow the welding of the wing 21 on the edge plate 1 7 while allowing the welder wheel 41 to follow the bank along the rail 23. Thus, the roller welding device 22 provides a sealed seal between the edge plate 17 and the partition plate 20, all along the shore.

FIG. 3 illustrates the following step of sealing between the secondary partition plate 20 and the carrier wall 1. For this purpose, an angle iron 19 is welded in a sealed manner to both the secondary partition plate 20 and the carrier wall 1. This welding is performed by a torch carriage 30 which replaces the knurling machine 41 on the guide rail 23. Two welding torches 31 extend from the carriage 30 each to one end of the angle iron 19 to each a weld bead respectively between the bracket 19 and the supporting structure 1 and between the bracket 19 and the partition plate 20. Between the two welding torches 31, the carriage 30 also comprises an arm 94, held at one of these end to the carriage 30 by an axis 95. This axis 95 allows the arm 94 a degree of freedom in a plane perpendicular to the direction of movement imposed by the guide rail 23. At the other end the arm 94 carries a pressure roller 96 in contact with the acute angle of the angle 19. This arm 94 is used to simultaneously press the bracket 19 against the carrier wall 1 and the secondary partition plate 20. It also serves to maintain a constant gap between the angle 19 and the heads of the welding torches 31. This action helps to guarantee the quality of the welds made. To increase the plating pressure exerted by the pressure roller 96 of the arm 94 on the bracket 19, the arm 94 incorporates a not shown spring cylinder. The pressure roller 96 has a shape adapted to not interfere with the advance of the carriage 30 and to cooperate with the angle 19 being in contact with it in the region of the acute angle 93. The outer tread of the roller 96 can for example form an angle less than or equal to 90 ° to ensure a better pressure between the bracket 19 and the carrier wall 1 on the one hand and the secondary partition plate 20 on the other.

A circulation box 33, shown in FIG. 4, is further welded to the angle iron 19 and passes therethrough into an orifice of the angle iron 19. The circulation box 33 consists of a rectangular profile opening towards the box 1 6 but which is closed in a side 34 opposite the box 16, that is to say on the side of the welding device. The circulation housing 33 further comprises a tab 35 resting on the carrier wall 1. In FIG. 4, the circulation box 33 is not represented in the plane of section, however, it is shown in the section plane in Figure 9. The orifice formed by the housing 33 in the angle has dimensions of 100x30mm and a housing 33 can be positioned every 20 meters.

When the welding of the edge plates 17 and angles 19 is made all around the periphery 12 of the secondary sealed barrier 3, the carrier wall 1, the secondary partition plates 20 and the sealed barrier 3 delimit a secondary closed volume 32. An orifice is then drilled in the secondary sealed barrier 3 to inject a gas into the closed volume 32 so as to perform an overpressure. Thus, any defect in the leaking welds can be detected before assembling the primary watertight barrier 5 and the primary insulating layer 4.

The tightness is tested by placing the secondary space under overpressure and the detection of gas escaping, in particular at the level of the welds of the metal membrane or the welds of the angles 19 and the edge plates 20. The gas put under overpressure in the primary or secondary space may be helium. A helium detection device, for example driven by a robot that follows the geometry of the sealed barrier, is then conducted along the welds of the pre-armed tank wall subassembly 12 on the block to detect any leakage. Alternatively, it is for example possible to inject ammonia into the volume of the subset 12 studied, so that the volume is overpressure. A developer is placed on the membrane and activated in contact with ammonia to reveal leaks.

When no leak is detected for the closed volume 32, the primary insulation layer 4 and the primary watertight barrier 5 can be mounted on the secondary barrier 3 after the closure of the orifice used for the injection of the test fluid. Thus, the heat-insulating elements of the primary insulating layer 4 are positioned on the secondary watertight barrier 3 and anchored to the carrier wall 1. As can be seen in FIG. 4, the primary watertight barrier 5 is then put in place and mounted on the set of primary heat insulating elements and is anchored in such a way watertight to a primary edge plate made of invar® 37 referred to in a primary edge box 36.

A primary vertical partition plate 38 is placed between the primary sealing barrier 5 and the secondary sealing barrier 3. The primary partitioning plate 38 is made of invar® 0.7mm thick and extends from the primary sealing barrier to the secondary sealing barrier.

At each edge plate 17 and 37 the primary partition plate 38 has a flange 39 and 40 extending parallel to the corresponding edge plate 17 or 37. Thus, similarly to the welding described with reference to FIG. 2, the wings 39 and 40 can be welded using the knurling machine 41. In particular, the welding of the flange 40 on the secondary edge plate 17 can be achieved by means of the wheel-welding device 22 described in FIG. 2. However, the arrangement of the watertight barrier 5 is made of so that there is a slight gap between the secondary partition plate 20 and the primary partition plate 38 so that the welds of the wings 40 and 21 are not superimposed. Thus, the welds of the two partition plates 20 and 38 are independent.

The welding of the wing 39 on the edge plate 37 is represented in FIG. 4. For this welding, the frame 24 is replaced by a frame 44 of greater height, the operation of the wheel sealer 41 remaining similar. Similarly to the secondary circulation box 33, a primary circulation box 42, shown in FIG. 8, is welded to the primary partitioning plate 38 and passes through the primary partitioning plate 38. The circulation box 42 is closed at its end 43 located outside the subset 12 of the pre-armed block 6. The circulation box 42 is welded to the upper part of the partition plate 38.

When sealing is performed for the two wings 39 and 40 over the entire contour of the tank wall subassembly 12 as shown in Figure 5, the sealing of the primary volume 45 delimited by the sealed barrier primary 5 e † the secondary watertight barrier 3 and the primary partitioning plate 38 can be tested similarly to the secondary volume 32.

The double bottom block 8 is then assembled with the other blocks 6. An assembly between two blocks 100 and 101 is shown in FIG. 6. Blocks 100 and 101, equipped with secondary insulating barriers 106, secondary sealing barriers 107 , primary insulating barriers 108, primary sealing barriers 109, are first assembled by welding their carrier walls 103. In the example of Figure 6, the block 100 comprises a cabin 1 12 connecting between varangues playing a role of stiffener. Boards 1 13 shown in the block 101, act as transverse primary stiffener in the bottom of the ship, in the space of the double hull. The block 101 further comprises an intermediate vessel carrying partition 1 14, called cofferdam.

A space 1 10 of dimension 1 1 1, at the junction between the carrier walls 103 of the blocks 100 and 101 is left unarmed to allow this welding operation. During the welding operation, it may happen that the wall of the double bottom 103 is deformed in an area 104. This deformation of the surface of the wall of the double bottom 103 is reflected, where appropriate, by a flatness deviation 105. Flatness gap can result in a bead along the weld bead. After the welding operation the flatness gap 105 is measurable and for example a few tens of millimeters.

When the blocks are assembled, the connection between the sub-assemblies 12 of pre-armed wall portions can be achieved at the connection zone 13, in particular by means of connecting strakes 45 for the sealed membranes 3 and 5. .

For this, it is first necessary to set up an insulating box. However the gap 105 poses the problem of the use of calibrated boxes.

To solve this problem, with reference to FIG. 7, prefabricated boxes 1 of reduced thickness are employed. These prefabricated boxes 1 15 are arranged on a bed formed in the lower parts or hollow of the wall of the double bottom, by cords 1 1 7 providing the support of compensation plates 1 1 6. The cords 1 1 7 are typically cords of polymer resin. The compensation plates can be made of wood, high density PU foam, typically a foam density of 200kg / m3. Thus, the combination of cords 1 17 and compensation plates 1 16 makes it possible to make up for the flatness of the support and the thickness difference between the box 1 1 5 with reduced thickness and the thickness of the insulating boxes pre-mounted on them. blocks 100 and 101. Once the continuity of the secondary insulating barrier is ensured, it is necessary to ensure the continuity of the secondary seal and then add the primary barrier.

The steps of such a connection will now be described with reference to Figures 8 to 10.

Heat-insulating elements 46 and 47 are put in place at the level of the secondary insulation layer between the secondary partitioning elements of the two adjacent sub-assemblies 12. In particular, a rim box 47 is positioned under the rim plate 17 and fills the space between the rim and the load-bearing wall 1. An intermediate box 46 is then juxtaposed with the edge box 47. In FIG. 8, the secondary circulation box 33 is shown in the section plane and it can thus be observed that the internal space of the box communicates with the volume 32. The edge box 47 and the intermediate box 46 each have a groove 48 and 49 on their lower surface, which accommodates the circulation box 33. In addition, the central box 46 has a vertical groove 50 on its lateral surface which extends to above the lower groove 48. The vertical groove 50 thus forms a chimney from the circulation housing 33 to the upper surface of the housing 46.

The strakes with raised edges are connected by a weld bead to the secondary edge plate 1 7. This operation is carried out symmetrically on the adjacent tank wall subassembly and corresponding to the side block 10 in order to form a secondary connection space. closed 51. The sealing of the secondary connection space 51 is then verified through a fitting 52 arranged in an orifice made above the groove 50. A gas is then injected into the secondary connection space to identify any leak, similar to the leak detection method presented above.

To carry out the communication between the different enclosures 32 and 51 delimited by the secondary partitioning elements 20, the circulation box 33 is then pierced by an orifice 99 illustrated in FIG. 9. This piercing can be carried out using a tool that is inserted through the connector 52 and the groove 50. The connector 52 is then plugged with a blanking plug. In this way, the fluids present in the secondary speakers 51 and 32 can circulate in several consecutive enclosures as indicated by the arrow 98 of FIG. 9.

The connection of the primary barrier 5, illustrated in FIGS. 9 and 10, is carried out, analogously to the secondary barrier 3, by the establishment of primary edge boxes 53, and primary central boxes 54, and the welding of the a connecting diaphragm 55, consisting of raised edge strakes, on the primary edge plates 37 to provide a primary connection enclosure 56.

For this purpose the primary boxes 53 and 54 comprise a groove on their upper surface which accommodates the primary circulation box 42. The imperviousness of the primary chamber is then tested via a primary connection tube 57 located at the above the flow box 42. Once this seal has been validated, the flow box 42 is then pierced through the connecting tube 57. This perforation can pass right through the primary circulation box 42 as it is illustrated by the opening 58 in Figure 10. The perforation can in an alternative embodiment through only the upper portion of the primary circulation housing 42. Then the connecting tube 57 is closed by a plug 59. Thus, the wall of The tank obtained has a primary space whose different compartments communicate, as indicated by the arrow 97, which makes it possible to circulate a flushing gas. Similarly, the secondary space consists of several compartments communicating with each other through the openings of the flow boxes 33, which allows to circulate a purge gas.

The method described above, aimed at producing closed volumes during the manufacture of a tank wall, is not limited to the construction of tank walls according to a pre-armed block assembly, and may in particular be applied any type of wall that needs to be interrupted during the construction phase of the wall. For example, such a method can be used to pre-manufacture the vessel wall when a scaffold attached to the supporting structure prevents the wall finish.

The cell walls described above correspond to an architecture comprising a so-called raised edge membrane, however, in other embodiments of the tank, the architecture of the walls may correspond to an architecture comprising a corrugated membrane. Such a membrane is for example described in document FR-A-2936784. To achieve a sealed volume, it is in this case possible to set up and weld pieces of sheet metal in the waves, the shape of the piece of sheet metal corresponding to the inner contour of a wave, so as to block every time the end of each wave located at a bank of the block.

The circulation between the primary and secondary enclosures described above is obtained by drilling the flow boxes 33 and 42. Alternatively, this circulation can be obtained by other means. For example, each circulation between the primary or secondary enclosures can be obtained directly by drilling the partition plates 20 or 38 obliquely through the connecting boxes and through the corresponding sealed barrier. In addition, the structure of the traffic case may be different while allowing communication between secondary volumes or primary volumes.

In service there are mechanical tensions in all primary and secondary watertight barriers. These mechanical stresses induced by thermal differences are taken up in the dihedra within of a pre-armed block. Figure 15 illustrates the recovery of these constraints by the implementation of a coupler designated 1 50 as a whole. This coupler 1 50 is disposed on the bisector of the angle formed by the two sections 1 51 of the carrier wall 1. This arrangement makes it possible to optimize the stresses by opposing a part of the forces resulting from the thermal variations of the sealing membranes arranged on either side of the bisector of the angle.

At the junction 1 54 of the two sections 1 51, an anchor plate 1 53 is welded. On this anchor plate 153 is fixed a mandrel 1 55 which cooperates with a rod 1 56. This rod 1 56 is threaded at its ends to be screwed into the mandrel 155 and the sleeve 1 57. At the end opposite to mandrel 1 55, the sleeve 1 57 maintains the secondary sealing membrane 1 60 applied to a counter plate 1 58. The counter plate 1 58 is supported on a piece of plywood 159 which sends the holding force via the box insulator 1 61 of the second insulating barrier on the carrier wall 1 51. The sleeve 157 further seals in the area of the waterproofing membrane where it is disposed. Then, as for a conventional subassembly 12 described in Figures 2 and 3, it is necessary to add the partitioning elements to obtain a sealed volume for the sealing tests.

The maintenance of the primary waterproofing membrane 1 62 is obtained according to the same principle by relying on the secondary subassembly. In this case, the rod 1 56 is not screwed to a mandrel but to the end of the sleeve 1 57 facing the inside of the tank. In the same way it is necessary to make the volume tight and validate this seal, proceeding as described for the primary barrier of a block in Figures 4 to 8. Thus the dihedron is integrated in a prefabricated block ready for use. final assembly.

According to another embodiment with reference to FIGS. 2 and 4, the attachments of the edge elements are made by gluing to obtain closed volumes 32 and 45. The elements involved in the gluing assembly are the partition plates 20 and 38. , the angle 19, the wall carrier 1, the edge plates 17 and 37. The bonding is performed by a crosslinkable adhesive or a heat-fusible adhesive. This bonding can also be obtained by using a thermoplastic piece, applied on the carrier wall or the membrane and then heated.

According to another embodiment not shown the partition plates of the secondary barriers have an upper wing and a lower wing to form a U. The upper wing is in contact with the edge plate and the lower wing is in contact with the bearing wall.

Like FIG. 1, FIG. 12 illustrates a sectional view of a vessel vessel intended to store a cold fluid. This tank consists of prefabricated wall blocks 6 including double bridge blocks 7, double bottom 8, and side blocks 10. This tank also comprises sections of upper chamfers 60 and lower chamfers 61 also prefabricated. In addition to the characteristics described in FIG. 1, the pre-cocking comprises the installation of a circuit for placing the zones of the secondary insulation layer 2 in communication. This circuit consists of a line 120 which is inserted in FIG. inside the double hull. This pipe 120 communicates with the zones of the secondary insulation layer 2 via connecting pipes 121 provided at each prefabricated block 6. For this, the wall of the inner shell 1 is pierced to allow the connection pipes 121 connected to the pipe 120 to lead into the secondary insulation layer 2. The network thus formed allows using a pump or a vacuum pump to suck the fluid contained in the areas placed in communication. It is also possible, with a booster or a compressor, to inject a gas, for example to inerter the areas concerned. These operations can be used in particular to test the tightness of the membranes.

With reference to FIG. 13, an angle structure of the vessel at the junction between a transverse partition 125 (cofferdam) and a longitudinal wall 126. will now be described. This structure comprises anchoring plates 124 which are integral with the supporting structure 135, namely the cofferdam 125 and the double bridge 126. The secondary waterproof barrier 128 is welded to a beam designated 131 as a whole. This beam 1 31 has in one corner, the role of a connecting ring and allows to fix the sealed barrier 128 to the supporting structure via the wings 124 and the anchor strips 123. In addition to ensuring the attachment of the secondary sealed barrier 128 to the supporting structure 135, the wings 124 and strips 1 23 seal zones 132, 133 and 134. These zones contain the secondary insulation elements 127 of the secondary thermally insulating barrier. In addition, this beam 1 31 serves to support the primary insulation elements 129 forming the primary thermally insulating barrier and anchoring to the primary sealing barrier 130.

A pipe 120 is inserted into the space of the double shell. It connects by connecting pipes 121 through the support structure 135 the boxes located in the areas of the secondary space 127. These areas are delimited by wings 124 and strips 123. The pipe 120 is connected to a vacuum pump and / or to a source of inerting gas, in particular for performing weld sealing tests.

To allow a zone-by-zone leak test, an isolation valve 122 is interposed between each connection pipe 121 and the pipe 120. Thus, it is possible to successively and independently vacuum each of the zones 132, 133 and 134. Finally, this communication circuit of the zones 132, 133, 134 also makes it possible to circulate fluids such as, for example, nitrogen.

According to another embodiment, with reference to FIG. 14, it is possible to isolate a subassembly during the pre-cocking of a block 6 of the ship's structure, to check the tightness of the secondary waterproof barrier. 3, by a temporary closure of the volume 32. For this a closing cheek 1 40 which is for example a steel element, is disposed on the banks of the secondary sealed barrier. This flange 140 is able to cooperate in a covering zone 1 41 with the supporting wall 1 and to cooperate with the secondary watertight barrier 3 in a second overlap zone 142. The flange 140 is pressed against the edge plate 1 47 to using 143 bolts regularly distributed lengthwise, while along the overlap zone 142. This fastening means is associated with a flexible seal 144 which makes it possible to seal the connection.

The flange 140 is also fixed to the load-bearing wall 1, by means of studs 145. Between the overlap zone 1 41 and the load-bearing wall 1, a flexible seal 144, for example a bead of mastic 144, is also applied. for sealing the assembly. Finally, the regular distribution of the bolts 143 and studs 145 is determined to allow the cheek 140 to withstand the injection of a gas under pressure to validate the tightness of the sealed barrier.

Once the tightness is verified, the cheek 140 is removed and the continuity of the elements in the connection area is finalized by the installation of the connection box as described in Figures 8 to 10.

According to another embodiment, the shape of the cheek makes it possible simultaneously to perform lateral sealing of the primary 5 and secondary 3 watertight barriers by perfectly marrying the edge of the subassembly 12. Thus, a single operation of mounting the removable cheek is necessary. to make it possible to validate the tightness of the volumes defined by the primary and secondary seals 3. After the tests are completed, a single disassembly operation is also necessary.

The tanks described above can be used in various types of installations such as land installations or in a floating structure such as a LNG tank or other.

Referring to Figure 1 1, a cutaway view of a LNG tank 70 shows a sealed and 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 barrier intended to be in contact with the LNG contained in the tank, a secondary sealed barrier arranged between the primary waterproof barrier and the double hull of the vessel, and two thermally insulating barriers arranged respectively between the primary watertight barrier and secondary watertight barrier, and between secondary watertight barrier and double hull 72. In a manner known per se, loading / unloading lines arranged on the upper deck of the ship can be connected, by means of appropriate connectors, to a marine or port terminal to transfer a cargo of LNG from or to the tank 71.

FIG. 11 shows an example of a marine terminal comprising a loading and unloading station 75, an underwater pipe 76 and an onshore installation 77. The loading and unloading station 75 is a fixed off-shore 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 pipes 73. The movable arm 74 can be adapted to all the jigs of LNG. A link pipe (not shown) extends inside the tower 78. The loading and unloading station 75 enables the loading and unloading of the LNG tank 70 from or to the shore facility 77. liquefied gas storage tanks 80 and connecting lines 81 connected by the underwater line 76 to the loading or unloading station 75. The underwater line 76 allows the transfer of the liquefied gas between the loading or unloading station 75 and the onshore installation 77 over a large distance, for example 5 km, which makes it possible to keep the tanker vessel 70 at great distance from the coast during the loading and unloading operations.

In order to generate the pressure necessary for the transfer of the liquefied gas, pumps on board the ship 70 and / or pumps equipping the shore installation 77 and / or pumps equipping the loading and unloading station 75 are used.

Although the invention has been described in connection with several particular embodiments, it is obvious that it is not limited thereto and that it comprises all the technical equivalents of the means described and their combinations if they are within the scope of the invention. The use of the verb "to include", "to understand" or "to include" and its conjugated forms does not exclude the presence of other elements or steps other than those set out in a claim. The use of the indefinite article "a" or "an" for an element or a step does not exclude, unless otherwise stated, the presence of a plurality of such elements or steps.

In the claims, any reference sign in parentheses can not be interpreted as a limitation of the claim.

Claims

1. A method for manufacturing a prefabricated block (6) suitable for manufacturing a sealed and thermally insulated tank, the block comprising a load-bearing wall and a sealed and thermally insulated tank wall mounted on the carrier wall by successively superposing a layer thermal insulation and a sealed barrier, the method comprising the steps of:

anchoring a subassembly of thermally insulating barrier (1 6, 36) on the carrier wall (1) of the block, the thermally insulating barrier subassembly being composed of a set of parallelepiped-shaped heat insulating elements juxtaposed according to a regular pattern;

placing a waterproof coating covering said insulating barrier subassembly, the implementation of the waterproofing coating comprising a step of positioning a sealed barrier element (1 5) on the insulating barrier subassembly (1 6). , 36) and covering said insulating barrier subassembly (1 6, 36), the sealed barrier element (1 5) being superimposed on the insulating barrier subassembly so that the sealed barrier element is parallel by relative to the carrier wall, and

a step of placing lateral partition elements (19, 20, 1, 7, 38, 37) around the insulating barrier subassembly (1 6, 36) over the entire contour of the insulating barrier subassembly, each of the lateral partition elements comprising a partition plate extending perpendicularly to the supporting wall, the lateral partition elements sealingly connecting the sealing barrier element (1 5) to the supporting wall (1), so as to forming a closed volume (32, 45) between the sealed barrier element and the carrier wall (1);

- Check the tightness of said closed volume (32, 45) by injecting gas into the closed volume so as to perform an overpressure.

The method according to claim 1, wherein the step of placing lateral partitioning elements (19, 20, 17, 38, 37) comprises a step of sealingly connecting the plate (20, 38) to the load-bearing wall and the first sealing barrier element.

3. Method according to one of claims 1 to 2, wherein the method further comprises, after the step of checking the tightness of said closed volume, the steps of:

placing a subset of primary insulating barrier (36) on the first watertight barrier element (15, 107), the primary insulating barrier subassembly being composed of a set of parallelepiped-shaped heat insulating elements juxtaposed according to a regular pattern;

a step of positioning a primary waterproof barrier element (1 5, 109) on the primary insulating barrier subassembly (36) and covering said primary insulating barrier subassembly (36), the primary barrier element being superimposed on the primary insulating barrier subassembly so that the primary barrier element is parallel to the carrier wall, and

a step of placing primary primary partitioning elements (37, 38) around the primary insulating barrier subassembly (36) over the entire contour of the primary insulating barrier subassembly, each of the primary lateral partitioning elements comprising a primary partitioning plate extending perpendicularly to the first watertight barrier element (1 5, 107), the primary lateral partitioning elements sealingly connecting the primary watertight barrier element (15, 109) to the first watertight coating, so as to forming a primary closed volume (45) between the primary watertight barrier element and the first watertight coating;

- Check the tightness of said primary closed volume (45)) by injecting gas into the closed volume so as to achieve an overpressure.

4. Method according to one of claims 1 to 3, wherein the verification of the tightness of a closed volume comprises a step injecting detectable test gas into said closed volume (32, 45, 51, 56) so as to generate an overpressure in said closed volume and a step of detecting the detectable gas outside said closed volume (32, 45, 51, 56).

The method of claim 4, wherein the test gas injected into said closed volume during the seal verification is helium or ammonia.

6. Method according to one of claims 1 to 5, further comprising the step of removably attaching the lateral partitioning elements to the sealed barrier element and the carrier wall.

7. Method according to one of claims 1 to 6, wherein the load-bearing wall of the block comprises a first pan and a second pan defining an angle, the thermally insulating barrier subassembly comprising a first thermally insulating barrier unit and a second thermally insulating barrier unit

wherein the step of anchoring the thermally insulating barrier subassembly to the carrier wall comprises:

- An anchoring step of the first thermally insulating barrier unit on the first panel of the carrier wall (1);

- An anchoring step of the second thermally insulating barrier unit on the second side of the carrier wall (1);

and wherein the sealed barrier element (1 5) is positioned on the insulating barrier subassembly so as to cover the first thermally insulating barrier unit and the second thermally insulating barrier unit;

- A step of fixing the sealed barrier with a coupler fixed to an anchor plate secured to the first panel and the second panel of the wall, the plate being disposed at an intersection between the first panel and the second panel, the coupler comprising a rod oriented from the plate on a bisector of the angle defined by the two panels, the coupler comprising in in addition to a sleeve sealingly traversing the waterproof coating and ensuring a fixing of the waterproof coating to the rod.

8. A method of manufacturing a sealed and thermally insulated tank, the method comprising the steps of:

- Manufacture two prefabricated blocks by implementing the method according to one of claims 1 to 7;

- Assembling the load-bearing walls of the two prefabricated blocks, a space (1 10) separating the subsets of the two blocks at a connection zone (13) of the assembled load-bearing walls of the two prefabricated blocks

- connect the watertight barriers and the insulation layers of the subsets of the two adjacent blocks at the connection area, the connection comprising the steps of

- juxtaposing a second subset of insulating barrier (46, 47, 53, 54) with respect to the first closed volume (32, 45) on the connection zone

(13) of the two carrier walls, the second subset of insulating barrier comprising heat-insulating elements (46,47) placed between the partition elements of the two subsets of insulating barriers of the two adjacent blocks;

- placing a second sealed barrier element (62, 55) on the second insulating barrier subassembly (46, 47, 53, 54), the second sealed barrier element being parallel to the carrier wall and covering said second insulating barrier subassembly,

- bonding the second watertight barrier element (62, 55) to the lateral partition elements (19, 20, 17, 38, 37) of the first watertight coating of each of the two adjacent blocks to form a second closed volume (51 , 56) adjacent to the first closed volume (32, 45) of each of the two adjacent blocks and separated from the first closed volume (32, 45) by the side partition members (19, 20, 17, 38, 37);

placing in fluid communication the first closed volume (32, 45) of each of the two adjacent blocks with the second closed volume (51, 56).

9. The method of claim 8, wherein the fluidic communication of the first closed volume with the second closed volume comprises the step of providing an opening in a lateral partitioning element between the first sealed volume and the second sealed volume.

10. The method of claim 9, further comprising a step of checking the tightness of the second closed volume (51) prior to the step of producing the opening.

11. The method of claim 1 0, wherein the verification of the tightness of the second closed volume is performed through an orifice (52, 57) formed in the second sealed barrier element and in which the opening is made. by drilling through said orifice (52, 57).

12. Method according to one of claims 9 to 11, wherein the step of producing an opening comprises a step of drilling the lateral partition element (19, 20, 1 7) through the second element. sealing barrier (62) and through the second insulating barrier subassembly (51, 47).

13. Method according to one of claims 9 to 1 2, wherein the opening is formed in a protruding piece and hollow (33, 42) of the partition element, the projecting piece extending in an opposite direction by relative to the first subset of insulating barrier (1 6, 36) and opening into said first closed volume (32, 45).

14. The method of claim 8, wherein the fluidic communication of the first closed volume with the second closed volume comprises the step of setting up a fluid circuit disposed outside the carrier wall and comprising a first pipe. connecting connection opening through the carrier wall (1) to communicate with the first closed volume and a second connecting pipe opening through the carrier wall to communicate with the second closed volume.

15. The method of claim 1 4, further comprising: - making a drilling of the carrier wall to the right of each of the volumes closed;

16. Method according to one of claims 8 to 15, wherein the step of placing side partition elements (19, 20, 1, 7, 38, 37) of a prefabricated block comprises a step of attaching an edge plate (17, 37) to the first thermally insulating barrier subassembly of the prefabricated block, said edge plate forming a bank of the watertight coating, the first watertight barrier element being sealingly bonded to the edge plate during the installation of lateral partition elements of the prefabricated block

the second watertight barrier element being sealingly connected to the edge plate when the second watertight barrier element (62, 55) is connected to the lateral partition elements (19, 20, 17, 38, 37) of the prefabricated block .

17. The method according to one of claims 8 to 1 6 combined with claim 3, the method further comprising the step of connecting the primary watertight barriers and the primary insulation layers of the subsets of the two adjacent blocks to level of the connection area of the load-bearing walls, the connection comprising the steps of:

- juxtaposing a second subassembly of primary insulating barrier (53, 54) relative to the first primary closed volume (45), the second subassembly of primary insulating barrier comprising primary heat insulating elements (53, 54) placed between the primary partitioning elements of the two primary insulating barrier subassemblies of the two adjacent blocks;

placing a second primary watertight barrier element (55) on the second primary insulating barrier subassembly, the second primary watertight barrier element being parallel to the supporting wall and covering said second primary insulating barrier subassembly (53, 54),

- bonding the second primary watertight barrier element (55) to the primary lateral partition elements (37,38) of the first sealed primary coating of each of the two prefabricated blocks to form a second closed primary volume (56) adjacent to the first volume primary closed (45) of each of the two prefabricated blocks and separated from the first primary closed volume by the primary lateral partition elements;

- Make an opening in a primary lateral partition element between the first primary closed volume (45) of each of the two prefabricated blocks and the second primary closed volume (56).

18. The method of claim 1 7, further comprising a step of checking the tightness of the second primary closed volume

(56) prior to the step of making the opening in the primary lateral partitioning element.

19. Prefabricated block suitable for manufacturing a sealed and thermally insulated tank, the block comprising: a load-bearing wall;

a sealed and thermally insulated tank wall mounted on the carrier wall by successively superimposing a thermal insulation layer and a sealed barrier, the vessel wall comprising a subset of thermally insulating barrier (1 6, 36; 1 27, 129) disposed on the carrier wall (1; 135) of the prefabricated block, the thermally insulating barrier subassembly being composed of a set of parallelepiped-shaped heat insulating elements juxtaposed in a regular pattern; a waterproof coating covering said subset of insulating barrier, the waterproof coating comprising

a sealed barrier element (1 5; 1 28, 130, 131) disposed on the insulating barrier subassembly (1 6, 36; 127, 129) and covering said insulating barrier subassembly (1 6, 36; 127); 129), the sealed barrier element (1 5; 1 28,130,131) being superimposed on the insulating barrier subassembly so that the sealed barrier element is parallel to the bearing wall,

lateral partitioning elements (19, 20, 17, 38, 37: 123,124) around the insulating barrier subassembly (1 6, 36: 127,129) along the entire contour of the insulating barrier subassembly, each of the partitioning elements lateral members having a partition plate extending perpendicularly to the carrier wall, the lateral partition members sealingly connecting the sealing barrier member (15; 128,130,131) to the supporting wall (1; 135) so as to forming a first closed volume (32, 45) between the sealed barrier element and the carrier wall (1; 135);

20. Watertight and thermally insulated vessel comprising:

two prefabricated blocks according to claim 19, the load-bearing walls of the two prefabricated blocks being assembled together, a space separating the subsets of the insulating barrier from the two prefabricated blocks assembled at a connection zone, the assembled load-bearing walls of the two prefabricated blocks

a second subset of insulating barrier (46, 47, 53, 54) arranged juxtaposed with respect to the first closed volumes (32, 45; 132, 133, 134) on the connection zone of the two assembled load-bearing walls, the second an insulating barrier subassembly comprising heat insulating elements (46, 47) located between the partition elements of the insulating barrier subassemblies of the two assembled prefabricated blocks;

a second sealed barrier element (62, 55) on the second insulating barrier subassembly (46, 47, 53, 54), the second sealed barrier element being parallel to the carrier wall and covering said second subassembly of an insulating barrier, the second sealed barrier element (62, 55) being bonded to the lateral partition elements (19, 20, 1, 7, 38, 37, 123, 124) of the sealed lining of each of the two insulating blocks assembled so as to form a second closed volume (51, 56) adjacent to the first closed volumes (32, 45, 132, 133, 134) and separated from the first volumes closed (32, 45, 132, 133, 134) by the side partition members (19, 20, 17, 38, 37, 123, 124); and

- A fluid communication means putting the first closed volumes (32, 45; 132, 134) in fluid communication with the second closed volume (51, 56).