TANK WITH AN ANCHOR ELEMENT

Abstract

The invention relates to a sealed and thermally insulated tank (100) for the storage of liquefied gas, comprising a first and a second tank wall meeting at an edge (103), and first and second primary thermally insulating barriers (12A, 12B) supported by a support. The tank also comprises an anchoring element (50) including: - an angle anchor rod (51) extending in a direction that intersects the direction of said edge, in an extension plane inclined at a non-zero angle to each of said first and second tank walls; - an anchor bar (52) anchored in the supporting structure and extending in a plane perpendicular to the direction of the anchor rod, a first end (51A) of the anchor rod cooperating with said anchor bar and a second end (51B) of the anchor rod cooperating with the anchor strip to transmit a tensile force between the strip anchoring and support.Figure for the abridged version: 1.

Description

Title of the invention: TANK COMPRISING A CORNER ANCHOR ELEMENT technical field

[0001] The invention relates to the field of sealed and thermally insulated tanks integrated into a load-bearing structure to contain a cold fluid, in particular to membrane tanks for containing liquefied gases, and in particular to mechanical anchoring devices usable in a wall of such a tank.

[0002] In particular, the invention relates to the field of sealed and thermally insulated tanks for the storage and / or transport of liquefied gases at low temperatures, such as tanks for the transport of Liquefied Natural Gas (LNG) at approximately -162°C at atmospheric pressure, Liquid Hydrogen (LH2) at -253°C at atmospheric pressure, Ammonia (NH3) at -30°C at atmospheric pressure, or Liquefied Petroleum Gas (also called LPG) having, for example, a temperature between -50°C and 0°C. These tanks can be installed on land or on a floating structure.

[0003] In the case of a floating structure, the tank may be intended for the transport of liquefied gas or for receiving liquefied gas used as fuel for the propulsion of the floating structure. Technological background

[0004] Sealed and thermally insulated tanks intended to receive a liquefied gas, in particular Liquefied Natural Gas (LNG) or Liquefied Petroleum Gas (LPG), are known, described for example in documents FR2102974 and FR2781557.

[0005] These tanks may be self-supporting or not.

[0006] These tanks have one or two sealing membranes associated with one or two thermally insulating barriers.

[0007] Moreover, these tanks are suitable for the storage of LPG or LNG, but not for the storage of liquid hydrogen at -253°C at atmospheric pressure. Summary of the invention

[0008] One idea underlying the invention is to provide a storage tank for a liquefied gas.

[0009] In particular, the proposed tank makes it easy to add an additional thermally insulating and leak-proof layer to the walls of a pre-existing liquefied gas storage tank. It notably allows for the conversion of a tank designed to store LNG or LPG, whether self-supporting or membrane-lined, into a tank adapted to contain liquid products at temperatures below the liquefaction temperature of LNG or LPG.

[0010] The tank according to the invention is advantageously adapted to store liquefied gases such as argon or liquid hydrogen, by facilitating the addition of one or more thermally insulating and sealed layers.

[0011] In other words, it is about facilitating the improvement of the thermal insulation performance of sealed and thermally insulating tanks.

[0012] According to one embodiment, the invention provides a sealed and thermally insulating tank for the storage of liquefied gas, in which the tank comprises a first tank wall and a second tank wall meeting at an edge and extending respectively along a first average plane and a second average plane inclined relative to each other so as to form at the junction between the first and second tank walls a corner zone, - the first tank wall comprising in a first thickness direction of the first tank wall: a first thermally insulating barrier and a first sealed membrane supported by the first thermally insulating barrier, - the second tank wall comprising in a second thickness direction of the second tank wall: a second thermally insulating barrier and a second sealed membrane supported by the second thermally insulating barrier,the first and second watertight membranes being fixed in a watertight manner to a corner anchoring strip along said edge and said tank also comprising a corner anchoring element comprising: , - an angle anchor rod extending in a direction that intersects the direction of said edge formed between the first and second walls, in an extension plane passing through said edge inclined at a non-zero angle with respect to each of said first and second tank walls, - an anchor bar fixed to a support, the anchor bar extending along a plane perpendicular to the direction of the anchor rod, a first end of the anchor rod cooperating with said anchor bar and a second end of the anchor rod cooperating with the anchor strip to transmit a tensile force between the anchor strip and the support.

[0013] According to one embodiment, the corner anchoring element further includes an end locking part which cooperates with the second end of the anchor rod to lock the second end of the anchor rod onto the corner anchoring strip.

[0014] According to one embodiment, said anchor bar has a central part with a polygonal or circular cross-section.

[0015] According to one embodiment, the anchor bar is formed of a hollow outer wall.

[0016] According to one embodiment, the hollow outer wall of the anchor bar contains a thermally insulating filling material.

[0017] According to one embodiment, the anchor bar is solid and formed from a single piece.

[0018] According to one embodiment, a central part of the anchor bar has a through hole which receives said anchor rod.

[0019] According to one embodiment, the first end of the anchor rod protrudes from the anchor bar by a length of less than 3 centimeters, so as to avoid any contact with the support.

[0020] According to one embodiment, the anchor rod is at least partially threaded and fixed against the anchor bar by a nut welded to the anchor bar on an external face of the anchor bar facing the support.

[0021] According to one embodiment, the nut is a spherical nut.

[0022] According to one embodiment, the corner anchoring element comprises a piece of corner stop having two lateral faces adapted to be applied against the corner anchor strip and a main face through which the second end of the anchor rod protrudes.

[0023] According to one embodiment, the second end of the anchor rod receives a locking nut which axially locks the angle stop piece and a watertight protective cover which completely covers said second end.

[0024] According to one embodiment, the second end of the anchor rod further receives at least one compressible clamping washer interposed between the locking nut and the angled stop piece.

[0025] According to one embodiment, the second end of the anchor rod further receives a spacer comprising: - a flat base interposed between the locking nut and said at least one compressible locking washer and - a sleeve which accommodates the anchor rod and passes through a central opening of said at least one compressible clamping washer.

[0026] The support can be made in many ways. In one embodiment, the support belongs to a load-bearing structure made of steel or concrete. In another embodiment, the support belongs to a thermally insulating barrier. In another embodiment, the support belongs to a membrane.

[0027] According to one embodiment, each of the first and second tank walls further comprises an underlying watertight membrane and a thermal barrier underlying insulating material placed between the underlying waterproof membrane and the load-bearing structure, the support being an element of the underlying waterproof membrane.

[0028] According to one embodiment, the support is a metal angle of the underlying waterproof membrane.

[0029] According to one embodiment, the underlying waterproof membrane is a primary waterproof membrane, each of the first and second tank walls further comprising a secondary waterproof membrane disposed between the primary waterproof membrane and the supporting structure, the underlying thermally insulating barrier comprising a secondary thermally insulating barrier disposed between the secondary waterproof membrane and the supporting structure and a primary thermally insulating barrier disposed between the secondary waterproof membrane and the primary waterproof membrane.

[0030] According to one embodiment, the first and second walls form a tank angle between them in the plane of extension of the anchor rod, the direction of the anchor rod divides this tank angle into two equal angles.

[0031] Such a tank can be part of an onshore storage facility, for example for storing LNG, or be installed in a floating structure, whether coastal or deep-water, including an LNG carrier, a floating storage and regasification unit (FSRU), a floating production and remote storage unit (FPSO), and others. Such a tank can also serve as a fuel tank in any type of ship.

[0032] According to a method for manufacturing a tank as described above, in order to make the second end of the anchor rod cooperate with the anchor strip so as to transmit a tensile force between the anchor strip and the support, said compressible clamping washer is compressed using a dedicated tool comprising: - a frame equipped with two arms oriented towards each other so as to form an angle identical to that between the first and second walls of the tank and connected by a central part of the frame, the central part comprising a central opening allowing the passage of the anchor rod, each of the arms of the frame being applied and locked against one of the walls of the additional anchoring strip so as to lock the frame onto the additional anchoring strip, - a piston jack supported by the central part of the frame, including a central opening through which the anchor rod passes, - a support piece having a shape adapted to compress said at least one compressible locking washer while allowing the nut to be tightened, by carrying out the following steps: - The frame of the dedicated tool is fixed onto the additional anchor strip, - the cylinder is actuated to press on the support piece which compresses at least one compressible clamping washer, - The nut is tightened through an access opening in the support piece.

[0033] The dedicated tool is then removed by detaching it from the additional anchoring strip.

[0034] According to one embodiment, a ship for the transport of a cold liquid product comprises a double hull and the aforementioned sealed and thermally insulated tank disposed in the double hull.

[0035] According to one embodiment, the invention also provides a transfer system for a cold liquid product, the system comprising the aforementioned vessel, insulated pipes arranged to connect the sealed and thermally insulated tank of the vessel to a floating or land-based storage facility and a pump to drive a flow of cold liquid product through the insulated pipes from or to the floating or land-based storage facility to or from the sealed and thermally insulated tank of the vessel.

[0036] According to one embodiment, the invention also provides a method for loading or unloading a ship, in which a cold liquid product is conveyed through insulated pipes from or to a floating or land-based storage facility to or from the sealed and thermally insulated tank of the aforementioned ship. Brief description of the figures

[0037] 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.

[0038] Fig. 1 is a partial perspective view of a first embodiment of the sealed and thermally insulating tank showing a corner area of ​​the tank;

[0039] The [Fig.2] is a partial cross-sectional view showing the tank of the [Fig.1];

[0040] Figure 3 is a partial perspective view with a cutaway showing the tank of the [Fig.l];

[0041] Fig. 4 is a partial perspective view of the corner area of ​​the sealed and thermally insulating tank of Fig. 1 during its manufacture, showing the support and corner anchoring elements;

[0042] Fig. 5 is a partial cross-sectional view of a second embodiment of the tank;

[0043] Fig. 6 is a partial cross-sectional view of a third embodiment of the tank;

[0044] Fig. 7 is an exploded perspective view of part of the corner anchoring element of Figures 1 and 6;

[0045] Fig. 8, Fig. 9, Fig. 10, Fig. 11, Fig. 12 and Fig. 13 are partial perspective views of the corner area of ​​the first embodiment of the tank during different successive manufacturing stages;

[0046] The [Fig. 14] is a schematic representation of a tool for compressing the clamping washers of the anchor rod;

[0047] The [Fig. 15] is a schematic representation of a support piece of the compression tool of the [Fig. 14];

[0048] The [Fig. 16] is a schematic representation of the extreme blocking part of the corner anchoring element of the tank of the [Fig.1];

[0049] The [Fig. 17] is a schematic cutaway representation of a methane tanker comprising the ship's tank and a loading / unloading terminal for this ship. Description of the implementation methods

[0050] In the present description, the terms "interior" and "exterior" are to be understood as describing a relative position with respect to an interior, respectively an exterior of the tank 100.

[0051] Identical or corresponding elements of the different embodiments will be referenced by the same symbols and will not be described each time.

[0052] Figures 1 to 6 and 8 to 13 illustrate a portion of a sealed and thermally insulating tank 100 comprising two walls 101, 102 forming a non-zero angle between them.

[0053] As mentioned above, the invention relates to the implementation of a liquefied gas storage installation, capable of storing a liquefied gas, in particular liquid hydrogen at a temperature of -253°C at atmospheric pressure or liquefied natural gas (LNG) at a temperature of about -162°C and at atmospheric pressure or other liquefied gases.

[0054] The installation 1 mainly comprises a supporting structure 40 and a sealed and thermally insulated tank 100 installed in the internal space of the supporting structure 40 ([Fig.3]).

[0055] The supporting structure 40 is described first.

[0056] The load-bearing structure 40 is polyhedral.

[0057] It can include any type of load-bearing walls. For example, it includes load-bearing walls made of steel or concrete. The load-bearing structure 40 comprises a first load-bearing wall 40A and a second load-bearing wall 40B.

[0058] The installation comprising the supporting structure 40 and the tank 100 can be designed to be located on land. The second supporting wall 40B is then typically horizontal, that is, located in a plane perpendicular to the direction of gravitational acceleration, within dimensional tolerances. It constitutes a bottom wall of the tank. The second supporting wall 40B can be located at ground level or possibly below ground level. The supporting structure 40 is here made of concrete.

[0059] In the following, we consider more specifically the case of an installation located on land where the second load-bearing wall 40B is horizontal. It is nevertheless specified that the following description applies to any orientation of the second load-bearing wall 40B with respect to the direction of gravitational acceleration.

[0060] In addition to the second load-bearing wall 40B, the load-bearing structure 40 includes a first load-bearing wall 40A. It extends, for example, vertically when the second load-bearing wall 40B extends horizontally.

[0061] Alternatively, the installation can be designed to be installed on board a floating structure, such as a ship. In this case, the load-bearing structure is a portion of a double hull formed by the floating structure. The second load-bearing wall may optionally be non-horizontal, and even be located in a plane parallel to the direction of gravitational acceleration, within dimensional tolerances, when the floating structure is at rest.

[0062] The tank 100 preferably comprises a plurality of first walls 40A which together form a polygonal cylindrical surface, having the polygon formed by a polygonal contour of the second load-bearing wall 40B as its base. The first load-bearing wall 40A extends here in a vertical direction, that is to say, in a direction perpendicular to the plane of the second load-bearing wall 40B, within dimensional tolerances.

[0063] Not shown in the drawings, at the end of the first load-bearing wall opposite the second load-bearing wall 40B, the load-bearing structure 40 includes a lid-bearing wall closing the internal space delimited by the first and second load-bearing walls 40A, 40B. This lid-bearing wall can support various equipment usable for conveying liquefied gas to or from this internal space.

[0064] Several embodiments of a sealed and thermally insulating tank 100 that can be installed in the internal space of the supporting structure 40 are now described with reference to Figures 1 to 13. The tank 100 comprises a first wall 101 disposed on the first supporting wall 40A and a second wall 102 disposed on the second supporting wall 40B.

[0065] Each first and second wall 101, 102 extending along a mean plane, the mean planes of the walls 101, 102 form an angle of 90° with each other. Alternatively, they can form an angle of a different non-zero value, for example between 80 and 145°.

[0066] The first and second walls are made up of layers of substantially uniform thickness which extend parallel to the average plane of the wall. The average plane of each wall is, for example, defined as the plane located at mid-thickness of the wall.

[0067] A corner area of ​​the tank 100 located in the vicinity of an edge 103 between the first and second walls 101, 102 is shown in figures 1 to 6 and 8 to 13.

[0068] The edge 103 between the two walls 101, 102 is here positioned at the internal angle between the two walls ([Fig. 1]). It could be positioned at the external angle between the two walls. In other words, since each of the two walls 101, 102 has an internal face facing the interior of the tank and an external face facing the exterior of the tank, the edge 103 is defined here as the intersection of the internal faces of the two walls. Alternatively, it could be defined as the intersection of the external faces of the two walls.

[0069] The inner and outer faces of the two walls are parallel to the average plane of each wall.

[0070] In general, the edge can also designate a place of intersection of the mean planes of the first and second walls 101, 102.

[0071] Figures show an example of a GST® type wall for an onshore LNG tank converted into a liquid hydrogen tank.

[0072] Thus, the structure of each of the first and second walls 101, 102 is that of a classic GST® type wall, as described for example in document FR2102974, to which an additional insulating and waterproof layer is added.

[0073] The first wall 101 comprises, along a first thickness direction DI ([Fig.3]) of the first tank wall perpendicular to the average plane of this first wall 101, from the outside to the inside of the tank: - a conventional stacking of two secondary and primary insulating and waterproof layers with a first secondary thermally insulating barrier 32A covered by a first secondary waterproof membrane 31A which supports a first primary thermally insulating barrier 22A equipped with a first primary waterproof membrane 21A, and - a first additional thermally insulating barrier 12A disposed against the first primary waterproof membrane 22A and supporting a first additional waterproof membrane 11 A.

[0074] The first additional thermally insulating barrier 12A is based on the stacking of the two primary and secondary insulating and waterproof layers anchored in the first load-bearing wall 40A of the load-bearing structure 40 ([Fig.3]).

[0075] A second wall 102 of the two walls 101, 102 comprises, along a second thickness direction D2 ([Fig.3]) of the second tank wall perpendicular to the mean plane of this second wall 102, from the outside to the inside of the tank: - a conventional stacking of two secondary and primary insulating and waterproof layers with a second secondary thermally insulating barrier 32B covered by a second secondary waterproof membrane 31B which supports a second primary thermally insulating barrier 22B equipped with a second primary waterproof membrane 21B, and - a second additional thermally insulating barrier 12B disposed against the second primary waterproof membrane 22B and supporting a second additional waterproof membrane 11B.

[0076] The second additional thermally insulating barrier 12B is based on the stacking of the two primary and secondary insulating and waterproof layers anchored in the second load-bearing wall 40B of the load-bearing structure 40 ([Fig.3]).

[0077] The different embodiments shown in the figures differ only in the arrangement of the insulating blocks forming part of the first and second additional thermally insulating barriers.

[0078] We will now describe, with reference to [Fig. 3], the structure of the secondary and primary layers of the first and second walls 101, 102 according to the first, second and third embodiments. These may be, for example, a vertical wall and a bottom wall of the tank.

[0079] As shown in this figure, in the vicinity of the junction between the first and second walls 101, 102, the first and second secondary thermally insulating barriers 32A, 32B comprise a corner structure including a corner block 80. This corner block 80 comprises two pairs of plates 81, 83, for example made of plywood, between which are glued two blocks of thermally insulating foam 82.

[0080] The corner block 80 extends along each of the first and second walls 101, 102 by means of insulating blocks 131. The thickness of the corner block 80 is preferably equal to the thickness of the foam block 133 of the insulating blocks 131.

[0081] The insulating blocks 131 may have a base plate 132, a foam block 133 disposed on the base plate 132, and a cover plate 135 disposed on the foam block 133. The base plate 132 and the cover plate 135 may be made of plywood. The foam block 133 may be made of polyurethane foam, optionally reinforced with fibers. In the described embodiment Here, these blocks correspond to the GST® technology marketed by the applicant and described in document FR2102974, for example. Reference can also be made to document US6035795 for the description of certain blocks.

[0082] Parallel beads of sealant (not shown) and wedges (not shown) are arranged between the corner block 80 or the insulating blocks 131 and the first and second load-bearing walls 40A, 40B.

[0083] The insulating blocks 131 and the corner block 80 shown in [Fig.3] together form a flat surface on which the first and second secondary waterproof membranes 31 A, 31B are glued.

[0084] The first and second secondary sealing membranes 32A, 32B are for example formed by a strip of flexible material which covers the insulating blocks 131 and the corner block 80. This flexible material can be a three-layer composite of glass fibers, aluminum and glass fibers.

[0085] Alternatively, the first and second secondary sealing membranes 32A, 32B may also include metal plates with corrugations similar to those described later for the primary sealing membrane.

[0086] The first and second primary thermally insulating barriers 22A, 22B are anchored on the insulating blocks 131 and the corner block 80 of the first and second secondary thermally insulating barriers 32A, 32B.

[0087] In practice, each of the first and second primary thermally insulating barriers 22A, 22B comprises a plurality of primary insulating blocks 23.

[0088] Between the corner block 80 of the first and second secondary thermally insulating barriers 32A, 32B, and the first and second primary airtight membranes 21A, 21B, each of the first and second primary thermally insulating barriers 22A, 22B comprises wooden blocks 62 which support primary angle brackets 25A, each primary angle bracket 25A being fixed to the blocks 62, for example by means of screws. Between the wooden blocks 62, an insulating plate 61 is glued, forming the corner between the first and second primary thermally insulating barriers 22A, 22B.

[0089] The insulating blocks 23, shown in figures 3 and 5, together form a flat surface on which the first and second primary waterproof membranes 21A, 21B are anchored.

[0090] Each of the first and second primary sealing membranes 21A, 21B consists of a plurality of sealing membrane elements in the form of overlapping metal plates. These metal plates are preferably rectangular in shape. The metal plates are welded together to ensure the sealing of the membrane. The metal plates are, for example, made of 1.2 mm thick stainless steel.

[0091] Alternatively, it can be any type of waterproof membrane, made for example in a manganese alloy or in Invar®: that is to say an iron and nickel alloy whose coefficient of expansion is typically between 1.2.106 and 2.106 K'.

[0092] The liquefied gas intended for storage in tank 100 may, in particular, be liquid hydrogen or liquefied natural gas (LNG), that is to say, a gaseous mixture consisting mainly of methane and one or more other hydrocarbons. The liquefied gas may also be ethane or liquefied petroleum gas (LPG), that is to say, a mixture of hydrocarbons from petroleum refining consisting essentially of propane and butane.

[0093] To allow the sealing membrane to deform in response to the various stresses experienced by the tank, particularly in response to the thermal contraction resulting from the loading of liquefied gas into the tank, the metal plates have a plurality of corrugations E1, E2 oriented towards the interior of the tank ([Fig. 1]). More specifically, each metal plate has two sets of perpendicular corrugations forming a regular rectangular pattern. Preferably, the corrugations run parallel to the edges of the rectangular metal plates. This is shown in [Fig. 1] for the first and second primary sealing membranes 21A, 21B.

[0094] The first and second primary waterproof membranes 21A, 21B are connected to each other by means of a metallic anchoring strip which will be described later together with the metallic anchoring strip connecting the first and second additional waterproof membranes 11A, 11B.

[0095] We will now describe, with reference to figures 1, 2, 3, 4 and 6, the structure of the additional layer according to the first, second and third embodiments.

[0096] The first and second additional thermally insulating barriers 12A, 12B comprise a row of edge insulating blocks 14, arranged along the direction of the edge 103 (Figures 1 and 5). The edge insulating blocks 14 are anchored to the underlying wall by any suitable means, for example using anchoring devices described in more detail later.

[0097] Each insulating edge block 14 comprises, for example, two outer plates that enclose a layer of insulating material, for example, insulating foam. The outer plates are, for example, made of plywood.

[0098] Figures 2, 5 and 6 show three embodiments of the tank which differ in the arrangement of the insulating edge blocks.

[0099] In the first embodiment of Figures 1 to 4 and 7 to 12, the edge insulating blocks 14 of the second wall 102 extend beyond the edge 103, opposite the edge of the edge insulating blocks of the first wall 101. First filler strips 141 are interposed between the edge of the insulating blocks of The edge 14 of the second wall and the load-bearing structure 40, along with the second layer of packing 142, are interposed between the edge of the insulating edge blocks of the first wall 101 and the insulating edge blocks of the second wall. The packing 141 and 142 serve to prevent natural convection and are made, for example, of glass wool or polymer foam.

[0100] In the second embodiment of [Fig.3], the edge insulating blocks of the first and second walls do not extend beyond the edge 103. A filler element 160 is provided along the edge 103 between the edge insulating blocks of the first and second walls to limit convection.

[0101] In the third embodiment, the insulating edge blocks of the first and second walls are formed: edge insulating blocks 14 are used in an angle comprising two parts making an angle between them equal to that between the walls 101, 102 of the tank.

[0102] For each embodiment, the edge insulating blocks 14 are extended, for each of the first and second walls 101, 102, by additional insulating blocks (not shown in the figures) which are similar to the insulating blocks of the secondary and primary thermally insulating barriers. It should be noted that the thicknesses of the insulating blocks used to form the various secondary, primary, and additional layers may differ.

[0103] In order to ensure effective thermal insulation for the storage of liquid hydrogen, the thickness of the additional insulating blocks of the thermally insulating barrier is greater than the thickness of the insulating blocks used for the first and second secondary and primary thermally insulating barriers.

[0104] Each of the first and second additional membranes 1 IA, 1 IB may comprise a corrugated stainless steel metal membrane, similar to that described above and shown in [Fig. 1] for the primary sealing membrane. This type of sealing membrane is notably described in publications WO-A-2010040922 or FR-A-2861060.

[0105] In order to connect the first and second additional sealing membranes 1 IA, 1 IB and the first and second primary sealing membranes 21A, 21B of the first and second wall 101, 102, the tank has two anchoring strips hereafter referred to as additional anchoring strip 15 and primary anchoring strip 25.

[0106] The additional anchoring strip 15 and the primary anchoring strip 25 each comprise a row of metal angle brackets 15A, 25A arranged at the edge 103. These angle brackets 15A, 25A are aligned along the direction of the edge 103. These angle brackets 15A, 25A are connected in a watertight manner in pairs along the direction of the edge 103 so as to ensure the watertightness of the overall additional waterproof membrane at the edge 103. The first and second waterproof membranes Additional 11A, 11B together with the anchoring strip 15 form a portion of the overall additional sealing membrane of the tank which is intended to be in contact with the liquefied gas contained in the tank 100.

[0107] As illustrated in figures 1 to 5, each angle 15A, 25A is in the form of a folded rectangular plate, with an L-shaped profile, and has two wings 16, 17, 26, 27.

[0108] The two wings 16, 17, 26, 27 of each angle bracket 15A, 25A form an angle with each other equal to the angle between the two walls 101, 102 of the tank 101, 102. The intersection between the two wings 16, 17 of the angle brackets 15A of the additional anchoring strip 15 forms the edge 103 between the walls 101, 102 of the tank. The intersection between the two wings 26, 27 of the angle brackets 25A of the primary anchoring strip 25 extends in a direction parallel to the direction of the edge 103 between the two walls 101, 102 of the tank.

[0109] Each of the two wings 16, 17 of one of said angle brackets 15A of the additional anchoring strip 15 extends parallel to one of the two walls 101, 102. A first 16 of these two wings 16, 17 rests on one or more edge insulating blocks 14 of the first additional thermally insulating barrier 11A of the first tank wall 101. A second wing 17 of these two wings 16, 17 rests on one or more edge insulating blocks 14 of the second additional thermally insulating barrier 11B of the second tank wall 102.

[0110] An end edge of the first additional sealing membrane 1 IA of the first tank wall 101 is anchored in a watertight manner, for example by means of a lap weld, on the first wings 16 of the row of angle brackets 15A forming the additional anchoring strip 15. Similarly, an end edge of the second additional sealing membrane 1 IB of the second tank wall 102 is anchored on the second wings 17 of the row of angle brackets 15A forming the additional anchoring strip 15.

[0111] The additional anchoring strip 15 is metallic and carries a plurality of corner joining pieces 69. Each corner joining piece 69 has two sleeves, one end of a corrugation El of each of the first and second additional waterproof membranes 1 IA, 1 IB A being received in one and the other of these sleeves. The corner joining piece 69 thus ensures a continuous connection between the corrugations El opposite the first and second additional waterproof membranes.

[0112] Each of the two wings 26, 27 of one of said angle brackets 25A of the primary anchoring strip 25 extends parallel to one of the two walls 101, 102 of the tank 100. A first wing 26 of these two wings 26, 27 rests on one or more edge insulating blocks 24 of the first primary thermally insulating barrier 22A of the first load-bearing wall 40A. A second wing 27 of these two wings 26, 27 rests on one or more insulating edge blocks 24 of the second primary thermally insulating barrier 22B.

[0113] An end edge of the first primary waterproof membrane 21A of the first wall 101 is anchored in a watertight manner, for example by means of a lap weld, on the first wings 27 of the angles 25A of the primary anchoring strip 25. Similarly, an end edge of the second primary waterproof membrane 21B of the second wall 102 is anchored on the second wings 27 of the angles 25A of the primary anchoring strip 25.

[0114] Each angle 15A of the additional anchoring strip 15 is anchored to the first and second primary thermally insulating barrier 22A, 22B by means of the angle anchoring elements 50 shown in the figures.

[0115] Each of these angle anchoring elements 50 comprises, as shown in [Fig. 6]: - an anchor rod 51, - an anchor bar 52 and - an extreme blocking section 57.

[0116] The anchor rod 51 extends along an extension direction X (figures 1 and 6) which crosses said edge 103 formed between the first and second wall 101, 102.

[0117] The anchor rod 51 extends here, in the case of a dihedral angle between two walls, perpendicularly to the edge 103.

[0118] The anchor rod 51 extends in an extension plane passing through said edge 103 and inclined at a non-zero angle Al, A2 with respect to each of said first and second wall 101, 102 of tank ([Fig.2]).

[0119] Here, the insulating blocks forming the first and second additional thermally insulating barriers 12A, 12B are of the same thickness along both tank walls 101, 102. The anchor rod 51 then extends along a bisecting direction of the tank angle formed between the two tank walls 101, 102. In other words, the extension plane of the anchor rod 51 divides the angle between the tank walls 101, 102 into two equal angles A1, A2.

[0120] In the case where the insulating blocks forming the additional thermally insulating barrier 12 along the two walls 101, 102 of the tank do not have identical thicknesses, the anchor rod 51 would then extend in a direction that does not bisect the tank angle formed between the two tank walls 101, 102.

[0121] Generally, the anchor rod 51 extends in a direction that intersects the intersection of the two flanges 26, 27 of the angle brackets 25A of the primary anchor strip 25 and the intersection of the two flanges 16, 17 of the angle brackets 15A of the additional anchor strip 15. More particularly, it extends in an extension plane passing through the intersection of the two flanges 26, 27 of the angle brackets 25A of the anchor strip primary 25 and the intersection of the two wings 16, 17 of the angles 15A of the additional anchoring strip 15.

[0122] The anchor bar 52 is anchored in the support. It has an elongated shape along a longitudinal direction Y ([Fig.6]). This longitudinal direction Y of the anchor bar 52 is perpendicular to the extension direction X of the anchor rod 51 ([Fig.2]).

[0123] More specifically, here, the anchor bar 52 is anchored on the primary anchor strip 25 which makes the watertight connection between the primary waterproof membrane elements 21 of the load-bearing walls of the load-bearing structure.

[0124] The anchor bar 52 is for example welded onto the anchor strip 25 connecting the first and second thermally sealed barriers.

[0125] More specifically, the longitudinal direction Y of the anchor bar 52 extends so as to form a non-zero angle with each of the walls 101, 102 of the tank.

[0126] It extends here between the wings 26, 27 of one of the angle brackets 25A of the primary anchoring strip 25. Here it forms an angle of 45° with each of the two wings 26, 27.

[0127] The anchor bar 52 has a central portion with a polygonal or circular cross-section. Here, the cross-section of the central portion of the anchor bar 52 is rectangular. A polygonal cross-section ensures good stiffness of the anchor bar and facilitates welding of this bar to the supporting structure 40. The anchor bar 52 thus provides effective load transfer.

[0128] The longitudinal ends of the anchor bar 52 are beveled in a manner adapted to the walls 101, 102. The longitudinal ends of the anchor bar 52 extend in practice in two planes forming an angle equal to the angle between the walls 101, 102 of the tank.

[0129] Here, the walls supporting the anchor bar are oriented at 90° to each other. The ends of the anchor bar are beveled at 45° each with respect to the longitudinal direction X of the bar. It is also economically advantageous to use anchor bars with ends oriented at 45° to the longitudinal direction X of the bar, because the production of these anchor bars by cutting a profile is done without waste.

[0130] The anchor bar 52 is formed of a hollow outer wall delimiting an inner housing 56. The inner housing 56 of the anchor bar 52 preferably houses a thermally insulating filling material, for example insulating foam or glass wool.

[0131] Alternatively, the anchor bar 52 can be solid in one piece.

[0132] The central part of the anchor bar has a through hole 56A which receives a first end 51A of the anchor rod 51. This through hole 56A can be drilled through the hollow outer wall and the filling material.

[0133] As can be seen in [Fig.7], the through orifice 56A preferably has dimensions slightly larger than those of the anchor rod 51. This allows for a useful clearance for mounting the corner anchoring element.

[0134] The first end 5IA of the anchor rod 51 extends from the anchor bar 52 outwards from the tank 100 ([Fig.7]). It extends from the anchor bar 52 by a length L adapted to avoid any contact with the supporting structure 40 ([Fig.2]). This length is, for example, less than or equal to 3 centimeters.

[0135] The anchor rod 51 is at least partially threaded.

[0136] Thus, the anchor rod 51 is fixed against the anchor bar 52 by a nut 53 screwed onto the first end 51A of the anchor rod 51 ([Fig. 2], 3 and 4). This nut 53 is preferably spot-welded to the anchor bar 52 to prevent any unscrewing and loosening of the nut 53. The nut 53 is welded here to the outer face of the anchor bar 52 facing the supporting structure 40.

[0137] It is possible to interpose, between the nut 53 and the outer face of the anchor bar 52, one or two more elastic clamping washers similar to the spring washers 59A described later.

[0138] A spherical nut is preferably used so as to subject the anchor rod 51 to tension.

[0139] A central part 5IC of the anchor rod 51 passes through the anchor bar 52 and the additional thermally insulating barrier 12 as well as the additional anchor strip 15.

[0140] A second end 5IB of the anchor rod 51 protrudes from the additional anchor band 15 and cooperates with the locking end part 57 ([Fig. 16]) to stress the anchor rod 51 in tension.

[0141] The end locking portion 57 comprises an angled stop piece 58 (Figures 2, 5, 6 and 16) which has the shape of a wedge. This angled stop piece 58 has two lateral faces 581 adapted to be applied against the wings 16, 17 of the additional anchoring strip 15 and a main face 582 through which the second end 51B of the anchor rod 51 protrudes (Figures 2, 16). It has a central through opening 583 which extends diagonally, in a direction inclined with respect to the two lateral faces 581 of the angled stop piece 58, and which opens onto the main face 582 of this angled stop piece 58. The anchor rod 51 passes through this through opening 583 (Figures 2, 16).

[0142] The second end 5IB of the anchor rod 51 receives a locking nut 59 which axially locks, along the direction of the anchor rod 51, the angled stop piece 58 against the additional anchor strip 15 of the additional waterproof membrane and a waterproof protective cover 571 which completely covers said second end 51B of the anchor rod 51.

[0143] The watertight protective cover 571 has a bell shape, the free edge of which is welded to the main face 582 of the wedge stop piece 58 all around the second end 51B of the anchor rod 51 in order to ensure sealing (figures 2 to 4).

[0144] In the example shown in the accompanying figures, spring washers 59A are also provided between the nut 59 and the wedge stop piece 58 (figures 2, 5, 6 and 16). These spring washers are optional.

[0145] The spring washers 59A are not flat washers. They comprise, for example, a flat portion and at least one curved or bent portion protruding from one side of the flat portion. The spring washers 59A exhibit elasticity in the tightening direction. They allow the wedge stop piece 58 to remain pressed against the additional anchoring strip 15 despite thermal contraction or thinning of the insulating blocks.

[0146] The number of 59A spring washers used is determined according to the required stroke and / or the desired compression. Depending on the requirements, the spring washers can be either parallel, i.e., with their curved or bent parts on the same side, or opposed, i.e., with their curved or bent parts alternately on one side and then the other of the flat part, or a combination of the two previous possibilities. The total stroke of the spring washers, in other words, the change in thickness of the spring washer stack during compression, and the force required for their compression, are determined according to the composition of the insulating blocks, stiffness, thickness, coefficient of thermal contraction, behavior under load, etc.

[0147] For example, between 2 and 10 spring washers 59A are used for tightening. Preferably, between 4 and 7 compressible spring washers 59A are used, positioned between the nut and the spring washers 59A. In the example shown in [Fig. 16], this involves 7 stacked Belleville-type washers, here in opposing positions. Alternatively, they can be stacked in parallel. Generally, the number of spring washers depends on the thickness of the insulating blocks of the underlying barrier.

[0148] Each spring washer 59A has a central opening allowing it to be threaded onto the anchor rod 51. The first spring washer 59A threaded onto the anchor rod 51 is positioned against the main face 582 of the angled stop piece 58.

[0149] The extreme blocking part 57 further includes a spacer 59B comprising a circular base 591 from which a sleeve 592 extends. The sleeve 592 extends around a central opening of the circular base 591 of the spacer 59B.

[0150] The sleeve 592 of the spacer 59B is threaded onto the anchor rod 51, through the central openings of the spring washers 59A. The circular base 591 of the spacer 59B comes against the last spring washer 59A of the spring washer stack. threaded onto the anchor rod 51. The central opening of the circular base 591 is smaller than the central opening of the spring washers, so that the nut 59 can be screwed against the circular base 591 of the spacer 59B.

[0151] The through opening 583 of the corner stop piece 58 has larger dimensions than those of the anchor rod 51. This through opening 583 also allows the passage of the sleeve 592 of the spacer 59B which can thus slide along the anchor rod 51.

[0152] The nut 59 is then screwed onto the anchor rod 51 and tightened against the circular base 591 of the spacer 59B.

[0153] The presence of the spacer 59B allows the number of spring washers used to be reduced by facilitating their tightening.

[0154] Alternatively, a non-compressible washer can be used instead of spacer 59B.

[0155] The stack of spring washers 59A is thus progressively compressed by tightening the nut 59 on the anchor rod 51, and the stack of spring washers 59A is locked between the nut 59 and the angled stop piece 58. Each clamping washer is compressed to approximately 80% of its maximum compression. The stack measures, for example, approximately 3.5 cm before compression, and the entire assembly is compressed by 7 millimeters. This compression ensures that the stresses generated by the thermal contraction of the additional waterproof membrane are absorbed and that the angled stop pieces 58 remain in contact with the additional anchor strip 15.

[0156] There are several methods for achieving this compression.

[0157] According to a first method, the compression of the spring washers 59A is achieved manually by tightening the nut 59 against the circular base 591 of the spacer 59B and the spring washers 59A. A torque of 20 N / m is applied to the nut. The nut 59 is then spot-welded to prevent loosening. The drawback of this method is that it may cause torsion to the anchor rod 51 and damage it. Two people are therefore required to perform the tightening: one holds the anchor rod 51 while the other tightens the nut 59.

[0158] According to a second method, the compression of the spring washers 59A is carried out using a dedicated tool shown in [Fig. 14] during use. In [Fig. 14], the nut 59 is not shown.

[0159] The dedicated tool comprises a frame 60 equipped with two arms 60A oriented towards each other so as to form an angle identical to that between the first and second tank walls 101, 102 and connected by a central part 60B of the frame 60. The central part 60B includes a central orifice 60C allowing the passage of the anchor rod 51.

[0160] The free end of one of the arms 60A includes a slot opening onto the free edge of this arm 60A, while the other arm has, near its free edge, an oblong opening.

[0161] The slot and the oblong opening each allow the passage of a mounting pin P provided in the additional anchoring strip 15 of the additional waterproofing membrane. The arms 60A of the frame 60 are thus applied against the walls of the additional anchoring strip 15. Each mounting pin P is threaded, and a nut is screwed onto each pin P so as to lock the frame 60 onto the additional anchoring strip 15 of the additional waterproofing membrane. The dedicated tool further includes a piston cylinder 90 supported by the central portion 60B of the frame 60. This cylinder 90 includes a central opening aligned with the central orifice 60C of the central portion 60B of the frame 60 to allow the passage of the anchoring rod 51.

[0162] The dedicated tool further includes a support piece 91 shown more particularly in [Fig. 15]. This support piece 91 has a shape adapted to compress the spring washers 59A while allowing the nut 59 to be tightened.

[0163] To this end, the support piece 91 comprises an annular support plate 92 having a central opening 95 through which the anchor rod 51 passes. One bearing face of the support plate 92 is oriented towards the cylinder 90. The support piece 91 further comprises a drop wall 93 extending along a portion of the circumference of the support plate 92. This drop wall 93 has a partially cylindrical shape. Here, the drop wall extends over half the circumference of the support plate 92.

[0164] The free edge 93A of the drop wall 93 is applied against the circular base 591 of the spacer 59B, around the nut 59 previously screwed onto the anchor rod 51.

[0165] It transmits to the stack of the spacer 59B and the spring washers 59A the pressure exerted by the hydraulic cylinder 90 on the support plate 92 of the support piece 91.

[0166] As the drop wall 93 extends only along part of the circumference of the support plate 91, the nut 59 remains accessible to a tightening tool through the support piece 91. An access opening 94 is defined between the support plate 92 and the drop wall 93.

[0167] A single operator can thus fix the frame 60, equipped with the hydraulic cylinder 90, onto the additional sealing membrane by tightening the nuts on the mounting pins P, then actuate the hydraulic cylinder 90 to compress the spring washers 59A, and finally tighten the nut 59 manually after compression. The tightened nut 59 is spot-welded to prevent loosening. The frame 60 and the hydraulic cylinder 90 are then removed.

[0168] For example, a 700 bar RCH120 hollow piston cylinder with a stroke of 8 mm is used.

[0169] The assembly of the sealed and thermally insulated tank 100 in the corner area may include the following steps:

[0170] - the anchor bars 52 are welded onto the angle brackets 25A of the anchor strip primary 25: an anchor bar 52 is for example welded onto each angle 25 of the primary anchor strip 25 ([Fig.7]),

[0171] - the anchor rod 51 is passed through the through hole 56A of the bar anchoring 52, it is fixed on the anchor bar 52 by screwing the nut 53 onto the first end 51A of the anchor rod 51, the nut 53 is welded onto the anchor bar 52 ([Fig.7]),

[0172] - the insulating edge blocks 14 of the second thermal barrier are installed additional insulation 12B against the angles 25A of the primary anchoring strip 25 ([Fig.8]). For this purpose, the edge insulation blocks 14 have a notch 145 adapted to house the anchor bar 52 and to allow the passage of the anchor rod 51 ([Fig.8]).

[0173] The edge insulation blocks 14 are fixed using anchoring devices ([Fig.10]) comprising, for example, a pin 150 protruding from the first and second primary waterproof membranes 22A, 22B. This pin 150 passes through an opening in the outer plate 148 of the edge insulation block 14, the outer plate 148 of the edge insulation block 14 being positioned against the primary anchoring strip 25. A washer and a nut tighten the outer plate 148 of the edge insulation block 14 against the primary anchoring strip 25 (Figures 2-4 and 10).

[0174] First wedges 141 are installed between each edge insulating block 14 of the second wall 102 and the first wing 26 of the corresponding angle 25A of the primary anchoring strip 25. Second wedges 142 are installed on the edge insulating blocks 14 of the second wall 102 and the wedges 141 in order to be interposed between these edge insulating blocks 14 of the second wall 102 and the edge insulating block 14 of the adjacent first wall 101 ([Fig. 10]).

[0175] The insulating edge blocks 14 of the first wall 101 are arranged against the first wings 26 of the primary anchoring strip 25 and fixed using anchoring devices similar to those described for the second wall 102 (figures 2 and 11).

[0176] The angle brackets 15A forming the additional anchoring strip 15 of the overall primary waterproof membrane 11 are arranged on the edge insulation blocks 14 forming the first and second additional thermally insulating barriers 12A, 12B: the first wing 16 of each angle bracket 15 is applied against the inner plate 149 ([Fig. 13]) of the corresponding edge insulation block 14 of the first wall 101 and the second wing 17 of each angle 15 is applied against the inner plate 149 of the corresponding edge insulating block 14 of the second wall 102.

[0177] Each angle bracket 15A of the additional anchoring strip 15 has dimensions corresponding to those of the edge insulating blocks 14 of the first and second thermally insulating barriers 12A, 12B. An anchoring element 50 is provided for each angle bracket 15A, centered on it. To this end, each angle bracket 15A has, at the center of its edge, a central opening for the passage of the anchoring rod 51. The corner stop piece 58 of each anchoring element 50 is positioned at this central opening.

[0178] The angle stop piece 58 is an added piece as described above which is preferably pre-assembled to the angle bracket 15A before installation.

[0179] Finally, the end locking portion is installed: here, a set of spring washers 59A and a spacer 59B are threaded around the second end 51B of the anchor rod 51 and tightened by a locking nut 59, for example, according to one of the methods described above. The cover 571 covers the second end of the anchor rod 51 with the spring washers 59A and the nut 59. It is welded to the main face 582 of the angle stop piece 58.

[0180] The corner anchoring element 50 is described here for use in a dihedral corner zone of the tank. It can also be used in a trihedral corner zone. The corner anchoring element is then positioned at the intersection of the edges formed between three tank walls.

[0181] The technique described above for making a tank wall can be used in different types of tanks.

[0182] It has been described here in the case of assembling an additional tank layer over an existing wall already comprising two secondary and primary watertight insulating layers, but it can also be used to constitute a primary layer of an LNG tank in an onshore installation comprising a single insulating and watertight layer or in a floating structure such as an LNG carrier or other vessel. It can also be used for assembling a single insulating and watertight layer on a supporting structure of an onshore tank or in a floating structure.

[0183] Furthermore, since all the tank walls have a similar structure, the description of a tank wall below applies by analogy to the other tank walls. Thus, the description below of Figures 1 to 16 is given in the context of a 90° tank angle; however, this description is also applicable by analogy to tank angles with other configurations, such as other walls forming 135° angles.

[0184] Finally, the description here describes the case of an insulating and waterproof layer added to a wall of the GST® type as described in document FR2102974. However, The tank described could also include Mark III type walls as described in document FR 2781557. The corner anchoring element could thus be used to add an additional thermally insulating barrier and waterproof membrane to other types of walls.

[0185] Thanks to the corner anchoring element, it is possible to anchor an additional waterproof and thermally insulating layer quickly and efficiently to a load-bearing wall or to a pre-existing tank wall, in particular to a primary waterproof membrane of an LNG storage tank.

[0186] With reference to [Fig. 17], a cutaway view of a methane tanker 70 shows a sealed and thermally insulating tank 100 of generally prismatic shape mounted in the double hull 72 of the ship 70. The wall of the tank 100 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 70, 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.

[0187] 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 100.

[0188] Figure 17 shows an example of a marine terminal comprising a loading and unloading berth 75, a subsea pipeline 76 and an onshore facility 77. The loading and unloading berth 75 is a fixed offshore facility 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 suitable for all LNG carrier sizes. An unshown connecting pipeline extends inside tower 78. The loading and unloading station 75 allows the loading and unloading of the LNG carrier 70 from or to the onshore facility 77. This facility includes liquefied gas storage tanks 180 and connecting pipelines 181 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 facility 77 over a long distance, for example 5 km, which allows the LNG carrier 70 to be kept a long distance from the coast during loading and unloading operations.

[0189] 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.

[0190] 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.

[0191] 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.

[0192] In claims, any reference sign in parentheses shall not be interpreted as a limitation of the claim.

Claims

1. Demands A sealed and thermally insulating tank (100) intended to be installed in a load-bearing structure for the storage of liquefied gas, in which the tank (100) comprises a first tank wall (101) and a second tank wall (102) meeting at an edge (103) and extending respectively along a first average plane and a second average plane inclined relative to each other so as to form at the junction between the first and second tank walls (100) a corner zone, - the first tank wall (101) comprising in a first thickness direction (Dl) of the first tank wall (101), from the outside to the inside of the tank: a first underlying thermally insulating barrier and a first underlying sealed membrane supported by the first underlying thermally insulating barrier,a first thermally insulating barrier (12A) and a first waterproof membrane (1 IA) supported by the first thermally insulating barrier (12A), - the second tank wall (102) comprising in a second thickness direction (D2) of the second tank wall from the outside to the inside of the tank: a second underlying thermally insulating barrier and a second underlying waterproof membrane supported by the second underlying thermally insulating barrier, a second thermally insulating barrier (12B) and a second waterproof membrane (1 IB) supported by the second thermally insulating barrier (12B), the first and second waterproof membranes being fixed in a watertight manner to a corner anchoring strip (15) along said edge (103) and said tank (100) also comprising a corner anchoring element (50) comprising:, - an angle anchor rod (51) extending along a direction (X) which intersects the direction of said edge (103) formed between the first and second walls (101, 102), in an extension plane passing through said edge (103) inclined at a non-zero angle (Al, A2) with respect to each of said first and second walls (101, 102) of tank, - an anchor bar (52) extending along a plane perpendicular to the direction (X) of the anchor rod, anchored on a support (25), the support (25) being an element of the underlying waterproof membrane, a first end (51 A) of the anchor rod (51) cooperating with said anchor bar (52) and a second end (51 B) of the anchor rod (51) cooperating with the anchor strip (15) to transmit a tensile force between the anchor strip (15) and the support.

2. Tank (100) according to claim 1, wherein the angle anchoring element (50) further comprises a locking part (57) which cooperates with the second end (51B) of the anchoring rod (51) to lock the second end (51B) of the anchoring rod on the angle anchoring strip (15).

3. Tank (100) according to claim 2, wherein the locking part (57) of the corner anchoring element (50) comprises a corner stop piece (58) having two lateral faces (581) adapted to be applied against the corner anchoring strip (15) and a main face (582) through which the second end (51B) of the anchoring rod (51) protrudes.

4. Tank (100) according to claim 3, in which the second end (51B) of the anchor rod (51) receives a locking nut (59) which axially locks the angle stop piece (58) and a watertight protective cover (571) which completely covers said second end (51B).

5. Tank (100) according to claim 4, wherein the second end (51B) of the anchor rod (51) further receives at least one compressible clamping washer (59A) interposed between the locking nut (59) and the angle stop piece (58).

6. Tank (100) according to claim 5, wherein the second end (51B) of the anchor rod (51) further receives a spacer (59B) comprising: - a flat base (591) interposed between the locking nut (59) and said at least one compressible clamping washer (59A) and - a sleeve (592) which accommodates the anchor rod (51) and passes through a central opening of said at least one compressible clamping washer (59A).

7. Tank (100) according to any one of claims 1 to 6, wherein a central part of the anchoring bar (52) has a through orifice (56A) which receives said anchoring rod (51).

8. Tank (100) according to any one of claims 1 to 7, wherein the first end (51 A) of the anchor rod (51) protrudes from the anchor bar (52), so as to avoid any contact with the support, advantageously of a length less than 3 centimeters.

9. Tank (100) according to any one of claims 1 to 8, wherein the anchor rod (51) is at least partially threaded and fixed against the anchor bar (52) by a nut (53) welded to the anchor bar (52) on an outer face of the anchor bar facing the support (25).

10. Tank (100) according to any one of claims 1 to 9, wherein the underlying waterproof membrane is a primary waterproof membrane, each of the first and second tank walls (101, 102) further comprising a secondary waterproof membrane disposed between the primary waterproof membrane and the supporting structure, the underlying thermally insulating barrier comprising a secondary thermally insulating barrier disposed between the secondary waterproof membrane and the supporting structure and a primary thermally insulating barrier disposed between the secondary waterproof membrane and the primary waterproof membrane.

11. Tank (100) according to any one of claims 1 to 10, wherein the first and second walls form between them, in the plane of extension of the anchor rod (51), a tank angle, the direction of the anchor rod divides this tank angle into two equal angles (Al, A2).

12. A method for manufacturing a tank according to claim 6, wherein, in order to make the second end (51B) of the anchor rod (51) cooperate with the anchor strip (15) so as to transmit a tensile force between the anchor strip (15) and the support, said compressible clamping washer is compressed using a dedicated tool comprising: - a frame (60) having two arms (60A) oriented towards each other so as to form an angle identical to that between the first and second tank walls (101, 102) and connected by a central portion (60B) of the frame (60), the central portion (60B) comprising a central opening (60C) allowing the passage of the anchor rod (51), each arms (60A) of the frame (60) being applied and locked against one of the walls of the additional anchoring strip (15) so as to lock the frame (60) onto the additional anchoring strip (15), - a piston jack (90) supported by the central part (60B) of the frame (60), including a central opening allowing the passage of the anchor rod (51), - a support piece (91) having a shape adapted to compress said at least one compressible clamping washer (59A) while allowing the tightening of the nut (59), by carrying out the following steps: - the frame (60) of the dedicated tool is fixed onto the additional anchoring strip (15), - the jack (90) is actuated to press on the support piece (91) which compresses said at least one compressible clamping washer, - the nut (59) is tightened through an access opening (94) in the support piece (91).

13. Vessel (70) for the transport of a cold liquid product, the vessel comprising a double hull (72) and a watertight and thermally insulating tank (100) according to any one of claims 1 to 11 disposed in the double hull.

14. Transfer system for a cold liquid product, the system comprising a vessel (70) according to claim 13, insulated pipes (73, 79, 76, 81) arranged to connect the sealed and thermally insulated tank (100) of the vessel to a floating or land-based storage facility (77) and a pump to drive a flow of cold liquid product through the insulated pipes from or to the floating or land-based storage facility to or from the tank (100) of the vessel.

15. A method of loading or unloading a ship (70), wherein a cold liquid product is conveyed through insulated pipes (73, 79, 76, 181) from or to a floating or land-based storage facility (77) to or from the sealed and thermally insulated tank (100) of the ship (70) according to claim 13.