Anchoring device for holding an insulating block

Abstract

An anchoring device for holding an insulating block against a support wall includes a clamping assembly (30) that includes a lower plate (31), an upper plate (32) parallel to the lower plate, and a rigid adjacent portion (33) that defines a minimum spacing between the lower plate and the upper plate. The anchoring device further includes a spacer portion (50, 150, 250, 350, 650) that is disposed below the lower plate and includes a central housing (51) through which an anchor rod passes, the spacer portion including an upper surface (56) configured to bear against the lower plate of the clamping assembly and a lower surface (57) for bearing on the insulating block.

Description

Technical Field

[0001] The present invention relates to the field of sealed thermal insulation tanks integrated into a support structure for containing cold fluids, in particular to membrane tanks for containing liquefied gases, and more particularly to mechanical anchoring devices that can be used in such tanks.

[0002] Sealed thermal insulation tanks can be used in various industries to store cold products. For example, in the energy field, liquefied natural gas (LNG) is a liquid with a high methane content that can be stored in onshore storage tanks or tanks on floating structures at approximately -163°C at atmospheric pressure. Liquefied petroleum gas (LPG) can be stored at temperatures between -50°C and 0°C, including the end points.

[0003] In the case of a floating structure, the tank can be used to transport liquefied gas or receive liquefied gas used as fuel to propel the floating structure. Background Art

[0004] For example, from documents WO-A-2014096600 and WO-A-2019110894, a sealed thermal insulation tank is known. The tank is used to store liquefied natural gas, is arranged in a support structure, and the walls of the tank have a multi-layer structure. That is, from the outside to the inside of the tank, a second-level thermal insulation barrier anchored against the support structure, a second-level sealing membrane supported by the second-level thermal insulation barrier, a first-level thermal insulation barrier supported by the second-level sealing membrane, and a first-level sealing membrane supported by the first-level thermal insulation barrier and used to contact the liquefied natural gas stored in the tank.

[0005] Each of the first-level thermal insulation barrier and the second-level thermal insulation barrier includes an assembly of modular first-level insulation blocks and second-level insulation blocks in a generally parallelepiped shape. They are juxtaposed and thus form a support structure for the corresponding sealing membrane. The insulation blocks are anchored to the support structure by anchoring devices that are fixed to the support structure and positioned at the level of the corners of the first-level insulation blocks and the second-level insulation blocks. Thus, each anchoring device cooperates with the corners of four adjacent second-level insulation blocks and with the corners of four adjacent first-level insulation blocks to hold them against the support structure. Summary of the Invention

[0006] Some aspects described herein are based on the following observations: Due to the sloshing phenomenon of the liquid contained in the tank, the tank wall may be subject to high and local compressive stresses. Now, the anchoring device is produced using components that are generally harder than the insulation blocks, so as to be able to reliably anchor the thermal insulation barrier while having a limited overall size. These stiffness differences result in a risk of flatness defects in the thermal insulation barrier in response to the compressive stress, especially when the thermal insulation barrier is substantially made of polymer foam. These flatness defects may lead to stress concentrations consistent with the anchoring device, which will damage the integrity of the sealing film supported by the thermal insulation barrier.

[0007] The idea underlying some aspects described here is to introduce flexibility in the direction of the compressive force from inside the tank for the anchoring device, so as to equalize the response of the thermal insulation barrier to the compressive stress. Another idea underlying some aspects described here is to allow the upper surface of the anchoring device to generally follow the movement of the upper surface of the insulation block during the use of the sealed thermal insulation film tank.

[0008] To this end, an anchoring device for holding an insulation block against a support wall is proposed herein, the anchoring device comprising:

[0009] A clamping assembly, which includes a lower plate, an upper plate parallel to the lower plate, a connecting member connecting the lower plate to the upper plate, and a spacer member disposed between the lower plate and the upper plate, the spacer member including a rigid abutting portion that defines a minimum spacing between the lower plate and the upper plate at the abutting position where the lower plate and the upper plate abut against the abutting portion, and

[0010] An anchoring rod protruding perpendicularly from the clamping assembly, the anchoring rod including a lower end and an upper end, the lower end being for attachment to the support wall, and the upper end being opposite to the lower end and coupled to the lower plate so as to be able to apply a traction on the lower plate in the direction of the lower end,

[0011] wherein the spacer member further includes an elastically compressible member that tends to maintain the lower plate and the upper plate in a separated position, the connecting member defines a maximum spacing between the lower plate and the upper plate in the separated position, the maximum spacing being greater than the minimum spacing, and the elastically compressible member is configured to elastically compress in response to a force tending to move the upper plate towards the lower plate until the lower plate and the upper plate abut against the abutting portion of the abutting position.

[0012] Due to the above features, the anchoring device can have a lower stiffness in response to the compressive force than the above prior art, and thus has the ability to elastically deform by squeezing between the separated position and the abutting position.

[0013] According to other advantageous embodiments, an anchoring device of the above kind may have one or more of the following features.

[0014] The spacer member that defines the maximum spacing between the lower plate and the upper plate can be produced in various ways. According to one embodiment, the connecting member includes: at least one connecting rod that is perpendicular to the lower plate and perpendicular to the upper plate and extends through the bored holes formed in the adjacent portion; a first adjacent element that is coupled to the first end of the connecting rod so that the upper plate is longitudinally restricted in movement relative to the connecting rod in the separated position; and a second adjacent element that is coupled to the second end of the connecting rod so that the lower plate is longitudinally restricted in movement relative to the connecting rod in the separated position, and the lower plate and / or the upper plate are mounted to slide relative to the connecting rod to be able to slide to the adjacent position.

[0015] The elastically compressible member can be arranged between the lower plate and the upper plate in various ways. The elastically compressible member can be installed in series or in parallel with the adjacent portion that defines the minimum spacing.

[0016] According to one embodiment, the elastically compressible member engages on the connecting rod.

[0017] According to an embodiment, the elastically compressible member bears against the adjacent portion and / or bears against the lower plate and / or the upper plate.

[0018] According to one embodiment, the bored hole formed in the adjacent portion includes a platform in which the elastically compressible member is arranged. Due to these features, the elastically compressible member can have small overall dimensions.

[0019] The elastically compressible member can be produced in various ways. According to one embodiment, the elastically compressible member includes a stack of spring washers. For example, 2 to 10 Belleville washers can be used to produce an elastic movement between 1 and 6 mm, including the end values.

[0020] The elastic movement between the separated position and the adjacent position of the upper plate and the lower plate preferably corresponds relatively precisely to the movement of the cover plate of the insulating block between the stationary state and the working state, where the stationary state corresponds to the empty tank and the ambient temperature, and the working state corresponds to the operating condition of the tank. This movement is caused by the thermal contraction of the insulating block and the contraction under the pressure load applied by the goods. Under the same conditions, preferably, the differential movement between the upper surface of the insulating block and the upper surface of the anchoring device should be considered, and less consideration should be given to the contraction of other parts of the anchoring device. According to one embodiment, the elastic movement is between 1 mm and 6 mm, preferably 3 mm.

[0021] According to one embodiment, the connecting member is configured to apply a static load on the elastically compressible member in a separated position. This type of static load (or preload) particularly allows for reliably supporting the underlying sealing membrane during the operation of constructing the tank, and the operation of constructing the tank is liable to generate local pressure on the tank wall (e.g., local drilling operation of the sealing membrane during construction or movement of workers or tools on the tank wall). The static load is, for example, about 1 kN.

[0022] According to one embodiment, the lower plate includes a central bore through which the upper end of the anchor rod passes, and the anchoring device includes: a nut that mates with the threaded portion of the upper end of the anchor rod; and one or more spring washers that are threadedly connected to the upper end of the anchor rod and are located between the nut and the lower plate so as to be able to apply an elastic force on the lower plate in the direction of the lower end of the anchor rod.

[0023] In this case, the clamping assembly preferably includes at least two connecting rods symmetrically arranged with respect to the central bore. Due to these features, the force can be distributed in the clamping assembly in a balanced manner.

[0024] According to one embodiment, the connecting rod or each connecting rod has its rotational movement restricted by spot welding on one or two plates or by separate locking nuts. The separate locking nuts are, for example, placed above the lower plate, below the lower plate, or partially within the lower plate.

[0025] According to one embodiment, the anchoring device further includes a spacer portion that is provided below the lower plate and includes a central housing through which the anchor rod passes. The spacer portion includes an upper surface configured to abut against the lower plate of the clamping assembly and a lower surface for supporting on the insulating block. The spacer portion is, for example, made of plywood to limit the thermal bridge. The spacer portion preferably has the same cross-section as the lower plate, which is a rectangular shape in the illustrated embodiment. It can be formed by a small number of elongate portions with simple shapes that are rigidly assembled with each other, such as nailed, screwed, and / or glued. The central housing is preferably filled with thermal insulation around the anchor rod, such as glass wool, packing, expanded polystyrene, or polyurethane foam.

[0026] According to one embodiment, the spacer portion is formed by four elongate portions with the same profile, and the inclined planes on the four elongate portions with the same profile form the corresponding walls of the central housing.

[0027] According to one embodiment, the spacer portion is formed by two opposing plates and two wedges disposed between the two opposing plates, and each of the two wedges and the two plates forms the corresponding wall of the central housing.

[0028] According to one embodiment, the thermal insulation includes a block of glass wool around the anchor rod.

[0029] According to one embodiment, the glass wool block includes notches within its thickness for receiving the anchoring rods.

[0030] According to one embodiment, the glass wool block includes at least one glass fiber mat, a sheet of kraft paper or polymer, the sheet being disposed between a pair of opposing walls of the glass wool block and the central housing.

[0031] According to one embodiment, the thermal insulator includes a polymer foam block that includes through-holes for receiving the anchoring rods.

[0032] According to one embodiment, the through-hole has a cross-section that widens from one of the upper and lower ends of the anchoring rod to the other of the upper and lower ends of the anchoring rod. In particular, according to one embodiment, the through-hole has a cross-section that widens from the upper end of the anchoring rod to the lower end of the anchoring rod.

[0033] According to one embodiment, the spacer portion includes blind holes that extend coaxially with the connecting rod and are adapted to receive a portion of the connecting rod.

[0034] According to one embodiment, the clamping assembly forms a second-stage clamping member for cooperating with the second-stage insulation barrier, the upper plate includes a central bore, and a stud protruding from the clamping assembly is screwed into the central bore on the side opposite to the anchoring rod, the stud carrying a first-stage clamping member for cooperating with the first-stage insulation barrier.

[0035] According to one embodiment, the anchoring device further includes a bushing that engages the lower end of the anchoring rod and is adapted to be fixed to the support wall, the bushing including a housing that receives the lower end of the anchoring rod to form a ball-and-socket joint connection.

[0036] According to one embodiment, the clamping assembly has a generally parallelepiped shape, and the lower plate and the upper plate have a rectangular profile.

[0037] According to one embodiment, the anchoring rod, the lower plate, and the upper plate are made of metal, and the adjacent portion is made of plywood or other rigid material that provides better thermal insulation than metal, such as polyurethane foam having a density greater than 200 kg / m 3 of density.

[0038] Other aspects described herein are intended to allow the anchoring device to cooperate with different parts of the insulation block.

[0039] One idea underlying the present invention is to introduce a spacer into the anchoring device, which, as described above, can or cannot exhibit flexibility in the direction of the compressive force from inside the tank. The spacer enables the holding force of the anchoring device to be transmitted towards the insulating block, for example towards the corner portions of the bottom plate of the insulating block, thereby avoiding compressing the polymeric foam of the insulating block. Another idea underlying the present invention is to provide a spacer that ensures such transmission of the holding force while limiting the thermal bridge and preferably remaining easy to assemble.

[0040] According to one embodiment, the present invention provides an anchoring device for holding an insulating block on a support wall, the anchoring device comprising:

[0041] A clamping assembly comprising a lower plate, an upper plate parallel to the lower plate, connecting members connecting the lower plate to the upper plate, and a spacer member disposed between the lower plate and the upper plate, the spacer member including a rigid abutment portion that defines a minimum spacing between the lower plate and the upper plate at the abutment position where the lower plate and the upper plate abut against the abutment portion, and

[0042] An anchoring rod projecting perpendicularly from the clamping assembly from the lower plate, the anchoring rod including a lower end and an upper end, the lower end being for attachment to the support wall, the upper end being opposite to the lower end and coupled to the lower plate so as to be able to apply a traction force on the lower plate in the direction of the lower end, and

[0043] A spacer portion provided below the lower plate and including a central housing through which the anchoring rod passes, the spacer portion including an upper surface configured to abut against the lower plate of the clamping assembly and a lower surface for supporting on the insulating block.

[0044] The spacer portion may have one or more of the features described above.

[0045] According to one embodiment, the present invention further provides an anchoring device for holding an insulating block on a support wall, the anchoring device comprising:

[0046] A clamping assembly comprising a lower plate, an upper plate parallel to the lower plate, connecting members connecting the lower plate to the upper plate, and a spacer member disposed between the lower plate and the upper plate, the spacer member including a rigid abutment portion that defines a minimum spacing between the lower plate and the upper plate at the abutment position where the lower plate and the upper plate abut against the abutment portion, and

[0047] An anchoring rod projecting perpendicularly from the clamping assembly from the lower plate, the anchoring rod including a lower end and an upper end, the lower end being for attachment to the support wall, the upper end being opposite to the lower end and coupled to the lower plate so as to be able to apply a traction force on the lower plate in the direction of the lower end, and

[0048] Spacer assembly, which is arranged below the lower plate. The spacer assembly includes a first spacer portion and a second spacer portion rigidly attached to the first spacer portion. The first spacer portion includes an upper surface configured to abut against the lower plate of the clamping assembly and a lower surface for abutting against the insulating block. The second spacer portion is made of polymer foam and includes a central housing through which the anchor rod passes.

[0049] According to one embodiment, the polymer foam has a density between 10 kg / m 3 and 60 kg / m 3 , including the end values, and more particularly between 10 kg / m 3 and 30 kg / m 3 , including the end values.

[0050] According to one embodiment, the second spacer portion includes a tongue received in a housing of a section complementary to the tongue included in the first spacer portion. The tongue can be pushed into the housing or glued and / or adhered and / or nailed and / or screwed to the first spacer portion.

[0051] According to one embodiment, the first spacer portion includes two plates and a wedge fixed together to define a housing.

[0052] According to one embodiment, the first spacer portion includes a blind hole that extends in line with the connecting rod and is adapted to receive a portion of the connecting rod.

[0053] According to one embodiment, the second spacer portion includes a flange extending on a side opposite to the tongue.

[0054] According to one embodiment, the present invention also provides a sealed thermal insulation tank for storing fluids. The tank includes a support wall, anchoring means fixed to the support wall, and a tank wall anchored to the support wall by means of the anchoring means. The tank wall, in the thickness direction from the outside to the inside of the tank, sequentially includes a thermal insulation barrier and a sealing film resting against the thermal insulation barrier.

[0055] Wherein, the thermal insulation barrier includes parallelepiped-shaped insulating blocks juxtaposed on the support wall, and the insulating blocks include a cover plate defining a support surface for the sealing film.

[0056] Wherein, using at least one of the above anchoring means, the lower end of the anchor rod is fixed to the support wall between a plurality of insulating blocks, and the lower plate of the anchoring means cooperates with the plurality of insulating blocks so as to clamp the plurality of insulating blocks in the direction of the support wall.

[0057] According to other advantageous embodiments, a tank of the above kind can have one or more of the following features.

[0058] According to one embodiment, the elastically compressible member is configured to hold the lower plate and the upper plate in a separated position in the empty state of the tank, and the upper plate of the anchoring device is aligned with the cover plates of the plurality of insulating blocks in the separated position to support the sealing film.

[0059] The insulating blocks can have various structures. According to one embodiment, the insulating block includes a bottom plate parallel to and spaced apart from the cover plate, and a fiber-reinforced polymer foam block disposed between the cover plate and the bottom plate, and the lower plate of the anchoring device directly or indirectly cooperates with the bottom plate without exerting any clamping action on the polymer foam block. For example, the lower plate of the anchoring device can cooperate with the bottom plate via rigid elements such as spacer portions, columns, and / or wedges made of, for example, plywood.

[0060] According to one embodiment, the insulating block includes: a bottom plate, an intermediate plate and a cover plate that are all parallel to the bottom plate and spaced apart from each other in sequence, and two fiber-reinforced polymer foam blocks disposed between the cover plate and the intermediate plate and between the intermediate plate and the bottom plate respectively. The lower plate of the anchoring device directly cooperates with the intermediate plate at the level of the corner region.

[0061] The stiffness of the elastically compressible member is preferably lower than the stiffness in the thickness direction of the insulating barrier adjacent to the anchoring device. According to one embodiment, the ratio between the stiffness of the elastically compressible member and the stiffness of an equivalent spring composed of a fiber-reinforced polymer foam having the same cross-section as the upper plate in the thickness direction of the tank wall is between 0.3 and 1, inclusive of the end values.

[0062] According to one embodiment, the thermal insulation barrier is a second-level thermal insulation barrier, the insulating block is a second-level insulating block, the sealing film is a second-level sealing film, the tank wall further includes a first-level thermal insulation barrier resting against the second-level sealing film and a first-level sealing film resting against the first-level thermal insulation barrier and for contacting the fluid contained in the tank. The first-level thermal insulation barrier includes first-level insulating blocks, and each of the first-level insulating blocks in the first-level insulating blocks is stacked on one of the second-level insulating blocks in the second-level insulating blocks.

[0063] Wherein the stud passes through the second-level sealing film in a sealed manner, and the first-level clamping member abuts against the plurality of first-level insulating blocks stacked on the plurality of second-levels in the direction of the support wall to hold the plurality of first-level insulating blocks in the direction of the support wall.

[0064] According to one embodiment, the fluid is a liquefied gas, such as liquefied natural gas, liquefied petroleum gas, liquefied ethylene.

[0065] Tanks of the above kind can form part of the following: onshore storage facilities; storage facilities placed on the seabed, for example for storing LNG, or installed in floating structures, in coastal or deep waters, in particular methane tankers, floating storage and regasification units (FSRUs), floating production storage and offloading (FPSO) units, etc.

[0066] According to one embodiment, a ship for transporting fluids comprises a double hull and the aforementioned tank disposed within the double hull. According to one embodiment, the double hull comprises an inner hull forming a support wall for the tank.

[0067] According to one embodiment, the present invention further provides a conveying system for fluids, the system comprising: the aforementioned ship; an insulated pipeline arranged to connect a tank installed in the hull of the ship to a floating or onshore storage facility; and a pump for driving the fluid from the floating or onshore storage facility through the insulated pipeline into the tank of the ship, or from the tank of the ship through the insulated pipeline into the floating or onshore storage facility.

[0068] According to one embodiment, the present invention further provides a method for loading or unloading a ship of the above kind, wherein the fluid is routed from a floating or onshore storage facility through an insulated pipeline to the tank of the ship or from the tank of the ship through an insulated pipeline to the floating or onshore storage facility. Description of the Drawings

[0069] The present invention will be better understood and other objects, details, features and advantages of the present invention will become more apparent during the following description of specific embodiments of the present invention given by way of non - limiting illustration with reference to the accompanying drawings.

[0070] Figure 1 Figure 1 is a sectional perspective view of the tank wall.

[0071] Figure 2 Figure 2 is a side view of the tank wall in the Figure 1 direction of arrow II, showing the anchoring device in a static state on the left side and in a compressed state on the right side.

[0072] Figure 3 Figure 3 is a side view of the anchoring device used in the Figure 2 tank wall in a static state.

[0073] Figure 4 Figure 4 is a half - view similar to Figure 2 showing another embodiment of the anchoring device.

[0074] ​​​​​​​​​Figure 5 Figure 5 is a perspective view of the spacer portion according to three embodiments.

[0075] Figure 6 Figure 6 is a perspective view of the spacer portion according to another embodiment.

[0076] Figure 7 Figure 7 is a perspective view of a thermal insulation block in which the spacer portion shown by Figure 5 and Figure 6 is received in the central housing.

[0077] Figure 8 Figure 8 is Figure 7 a top view of the thermal insulation block shown.

[0078] Figure 9 Figure 9 is Figure 7 and Figure 8 a cross-sectional view of the thermal insulation block shown taken along line A-A in Figure 8 .

[0079] Figure 10 Figure 10 is a perspective view of a different thermal insulation in which the spacer portion shown by Figure 5 and Figure 6 is received in the central housing.

[0080] Figure 11 Figure 11 is a cross-sectional view similar to Figure 3 showing another embodiment of the anchoring device.

[0081] Figure 12 Figure 12 is Figure 11 a partial top perspective view of the spacer portion of the anchoring device shown.

[0082] Figure 13 Figure 13 is a schematic view above the tank wall of Figure 2 showing the position of the anchoring device.

[0083] Figure 14 Figure 14 is a perspective view of another insulation block that can be used for the Figure 1 tank wall.

[0084] Figure 15 Figure 15 is a perspective view of two insulation blocks according to another embodiment, where one insulation block is Figure 14 ​​​​​​​​​​​​​​​​​​​​​Of the type shown, held in place by an anchoring device.

[0085] Figure 16 Figure 16 is Figure 15 A perspective view of the spacer assembly of the anchoring device in

[0086] Figure 17 Figure 17 Is a schematic sectional view of a tanker cargo tank and a terminal for loading / unloading the tank. Detailed Description of the Invention

[0087] As a matter of convention, the terms "lower" and "upper" are used to define the relative position of one element with respect to another in the external or internal direction of the tank, respectively, as in the Figure 1 Horizontal wall shown. However, the following description applies to any wall, regardless of its orientation in the gravitational field.

[0088] In Figure 1 A multi-layer structure of a hermetic thermal insulation tank wall 1 for storing a liquefied fluid such as liquefied natural gas (LNG) is shown. The tank wall 1 includes, in the thickness direction from the outside to the inside of the tank, in sequence: a second-stage thermal insulation barrier 3 held on a support wall 2; a second-stage sealing film 4 resting against the second-stage thermal insulation barrier 3; a first-stage thermal insulation barrier 5 resting against the second-stage sealing film 4; and a first-stage sealing film 6 for contacting the liquefied natural gas contained in the tank.

[0089] The support wall 2 can be formed particularly by the hull or double hull of a ship. The support wall 2 generally forms part of a support structure that includes a plurality of walls defining the general shape of the tank, and the general shape of the tank is generally a polyhedral shape.

[0090] The second-stage thermal insulation barrier 3 includes a plurality of second-stage insulation blocks 7, which are anchored to the support wall 2 by an anchoring device 20 to be described in detail below. The second-stage insulation blocks 7 have a generally parallelepiped shape and are arranged in parallel rows.

[0091] The second-stage sealing film 4 includes a continuous layer of metal battens 8 having a raised edge. The metal battens 8 are welded to parallel welding supports through their raised edges, and the parallel welding supports are fixed in grooves 9 formed in the cover plates of the second-stage insulation blocks 7. The metal battens 8 are made of, for example, Made of: that is, an alloy of iron and nickel, whose coefficient of thermal expansion is generally between 1.2×10 -6 and 2×10 -6 K -1 Between.

[0092] ​​​​The first-level thermal insulation barrier 5 includes a plurality of first-level insulation blocks 11, which have a generally parallelepiped shape and length and width dimensions that are the same as the length and width dimensions of the second-level insulation blocks 7. Each of the first-level insulation blocks 11 is positioned to align with one of the second-level insulation blocks 7 and is aligned with it in the thickness direction of the tank wall 1.

[0093] The first-level sealing film 6 can be produced in various ways. Here, it includes a continuous layer of metal battens 8 having raised edges. Like in the second-level sealing film 4, the metal battens 8 are welded to parallel welding supports through their raised edges, and the parallel welding supports are fixed in the grooves formed in the cover plates of the first-level insulation blocks 11.

[0094] In Figure 1 , a second-level insulation block 7 is omitted to show the thickness shim 12 and the bead 13 (bread, bead of mastic) for compensating for the flatness defects of the support wall 2. Positioning shims (not shown) as described in the published WO-A-2018069585 can also be provided.

[0095] The anchoring devices 20 are preferably positioned at the level of the four corners of the second-level insulation blocks 7 and the first-level insulation blocks 11. Each stack including the second-level insulation blocks 7 and the first-level insulation blocks 11 is anchored to the support wall 2 by four anchoring devices 20. In addition, each anchoring device 20 cooperates with the corners of four adjacent second-level insulation blocks 7 and the corners of four adjacent first-level insulation blocks 11.

[0096] Reference Figure 2 , the structure of the second-level insulation block 7 according to an embodiment is seen in more detail. Here, the second-level insulation block 7 includes an insulating polymer foam layer 16 sandwiched between a bottom plate 14 and a cover plate 15. The bottom plate 14 and the cover plate 15 are made of plywood, for example. The insulating polymer foam layer 16 is glued to the bottom plate 14 and the cover plate 15. The insulating polymer foam can particularly be a polyurethane-based, optionally fiber-reinforced foam.

[0097] Figure 13 More precisely shown is the positioning of the anchoring device 20 between the corners of four adjacent second-level insulation blocks 7 as seen from above. The anchoring device 20 is represented by the contour of the clamping assembly 30. It can be seen that the bottom plate 14 of each second-level insulation block 7 includes a cutout 52 at the level of its corner region to leave a gap 55 in the form of a rectangular chimney for receiving the anchoring device 20.

[0098] The cover plate 15 and the insulating polymer foam layer 16 of the second-stage insulating block 7 include a rectangular chimney-shaped recess 53 that exposes the corner portion 54 of the bottom plate 14. The corner portion 54 is used to directly support the anchoring device 20 thereon, or indirectly support it via, for example, a spacer portion 50 described below or a rigid element such as a corner post rigidly attached to the bottom plate 14.

[0099] Next, refer to Figure 2 and Figure 3 to describe the structure of the anchoring device 20 according to an embodiment.

[0100] The anchoring device 20 generally includes a clamping assembly 30 and an anchoring rod 22. The lower end of the anchoring rod 22 is received in a bushing 23, and the base of the bushing is welded to the support wall 2 at the central position of the gap 55 between the corner regions of four adjacent second-stage insulating blocks 7. The bushing 23 forms a ball-and-socket joint for the anchoring rod 22. For example, it houses a nut 18, and the lower end of the anchoring rod 22 is screwed into this nut. The anchoring rod 22 extends in the thickness direction of the tank wall 1 and passes between adjacent first-stage insulating blocks 22.

[0101] The clamping assembly 30 sequentially includes a lower plate 31, a spacer block 33, and an upper plate 32 in the thickness direction. The lower plate 31 and the upper plate 32 have a generally rectangular parallelepiped shape, which includes two opposite larger faces parallel to the support wall 2. The profile of the spacer block 33 is also rectangular and has the same dimensions. Alternatively, the shape of the profile of the clamping assembly 30 can be different, for example, hexagonal or circular.

[0102] The lower plate 31 is held by the anchoring rod 22 so that it abuts against the corner portion 54 of each of the four adjacent second-stage insulating blocks 7 in the direction of the support wall 2. In the illustrated embodiment, a spacer portion 50 is provided between the lower plate 31 and the corner portion 54 of each of the second-stage insulating blocks 7, thereby transmitting the clamping force to the bottom plate 14.

[0103] The upper end 44 of the anchoring rod 22 is engaged through a central bore 41 of the lower plate 31 and engaged in a housing 45 formed in the spacer block 33. A nut 42 is threadedly engaged with the thread formed at the horizontal level of the upper end 44 of the anchoring rod 22 to hold the lower plate 31 in the direction of the support wall 2.

[0104] In the illustrated embodiment, the anchoring device 20 further includes one or more Belleville-type spring washers 43. The spring washers 43 are threadedly connected to the anchoring rod 22 and located between the nut 42 and the lower plate 31, which allows the second-stage insulating blocks 7 to be elastically anchored to the support wall 2. In addition, a locking member is advantageously locally welded to the upper end of the anchoring rod 22 to prevent the nut 42 from loosening.

[0105] The spacer block 33 also includes two boreholes passing through it in the thickness direction of the tank wall, and two fixing bolts 34 are engaged in the two boreholes to connect the lower plate 31 and the upper plate 32 to two opposite faces of the spacer block 33. More precisely, the lower end 35 of each fixing bolt 34 is threadedly connected and screwed into a threaded hole 38 in the lower plate 31. A separate lock nut 37 is also screwed onto the lower end 35 against the upper surface of the lower plate 31 to lock the fixing bolt 34 in place in the lower plate 31. In a manner not shown, the separate lock nut 37 can also be placed against the lower surface of the lower plate 31.

[0106] Each fixing bolt includes a head 36 at opposite ends, such as a tapered head slidably received in a borehole 46 in the upper plate 32. Figure 3 and Figure 2 The abutting position where the head 36 shown on the left side abuts against the bottom of the borehole 46 defines the position of the maximum spacing between the plates 32 and 31. The size of this maximum spacing is defined by the available length of the fixing bolt 34 between the lower plate 31 and the upper plate 32. This length can be finely adjusted during manufacturing by screwing the engaged length in the threaded hole 38.

[0107] The spacer block 33 includes a lower face and an upper face 48 both parallel to the plates 32 and 31. The thickness of the spacer block 33 between the lower face and the upper face 48 defines the minimum spacing between the lower plate 31 and the upper plate 32. The minimum spacing is reached at the abutting position shown on the Figure 2 right side, where the lower plate 31 and the upper plate 32 abut against the lower face and the upper face 48 of the spacer block 33.

[0108] The dimensional difference between the minimum spacing and the maximum spacing is indicated by the arrow 40 and corresponds to the sliding clearance of the head 36 in the borehole 46. Its size is determined according to the structure of the tank wall and the operating conditions of the tank, such that during the use of the tank, the upper plate 32 can generally follow the depression of the cover plate 15 of the secondary insulation block 7, which is particularly caused by the thermal contraction experienced by the tank wall 1 during operation and the action of static and dynamic pressures. These pressures may particularly cause creep of the insulating polymer foam layer 16. This size is typically a few millimeters.

[0109] A spring element 39, such as a Belleville washer, is engaged on the two fixing bolts 34 between the spacer block 33 and the upper plate 32, and holds the plates 32 and 31 in Figure 3The separation position shown. More precisely, the spring element 39 creates a clearance equal to the dimensional difference 40 between the spacer block 33 and the upper plate 32. In response to the pressure applied to the upper plate 32, the Belleville washer 39 is compressed and gradually eliminates this clearance until the lower face 49 of the upper part 32 abuts against the upper face 48 of the spacer block 33.

[0110] More precisely, here, the spring element 39 is received in the large-diameter stage 19 of the borehole that receives the fixing bolt 34 and bears against the shoulder at the bottom of the stage 19. In the adjacent position, the spring element 39 is completely accommodated inside the stage 19.

[0111] According to one embodiment, each fixing bolt 34 carries a stack of Belleville washers, which are arranged in turn in mutually inverted positions, preferably an odd number, for example five, such that the two ends of the stack constitute the maximum diameter of the Belleville washers.

[0112] The fixing bolt 34 is preferably configured to generate a compressive preload on the spring element 39 in the rest position, such that the upper plate 32 can receive a moderate load without being pressed down. For example, a preload of about 1000 N is applied, which makes it possible to support the weight of an adult man who may walk in unison with the anchoring device 20 during the construction of the tank.

[0113] The stiffness of the spring element 39 is determined according to the structure of the tank wall and the operating conditions of the tank, such that during the operation of the tank, the upper plate 32 can generally follow the depression of the cover plate 15 of the second-stage insulation block 7, which is caused in particular by the thermal contraction experienced by the tank wall during operation and the action of static and dynamic pressures. These pressures may particularly cause creep of the insulating polymer foam layer 16.

[0114] It will be noted that the spring element 39 can be positioned differently to achieve the same function. For example, the fixing bolt 34 can be inverted such that the bolt head 36 is on the same side as the lower plate 31, and then the spring element 39 is positioned between the lower plate 31 and the spacer block 33. In another variant not shown, the spacer block 33 is divided into two parts in the thickness direction, and the spring element 39 is arranged between these two parts.

[0115] In Figure 4 In another variant shown in a half-view, the bolt head 36 is positioned in the upper plate 32, and the spring element 39 is positioned between the lower plate 31 and the spacer block 33. In this case, the upper plate 32 and the spacer block 33 slide together relative to the fixing bolt 34. In addition, the restricted rotation of the fixing bolt 34 relative to the lower plate 31 can be achieved by spot welding or a locking nut not shown. In Figure 4In [the figure], plates 32 and 31 are shown in an adjacent position.

[0116] The tank wall 1 can be limited to the second-stage insulation barrier 3 and the second-stage sealing film 4 to produce a single-film tank. In the presence of the first-stage insulation barrier 5 and the first-stage sealing film 6, the anchoring device 20 further includes a first-stage platform. For this purpose, the upper plate 32 has a threaded bore 47 at its center, in which the threaded base of the stud 27 for anchoring the first-stage insulation block 11 is installed. The stud 27 passes through the bore formed by the metal strip plate 8 that penetrates the second-stage sealing film 4. The stud 27 includes a flange that is welded around the bore at its periphery to provide a seal for the second-stage sealing film 4.

[0117] The first-stage platform of the anchoring device 20 further includes a first-stage support plate 28, which is supported on the support areas formed in each of the four adjacent first-stage insulation blocks 11 in the direction of the support wall 2 to hold them on the second-stage sealing film 4. In the illustrated embodiment, each support area 29 is formed by a protruding portion of the bottom plate of the first-stage insulation block 11.

[0118] The nut 29 mates with the thread formed at the upper end level of the stud 27 to fix the first-stage support plate 28 to the stud 27. In the illustrated embodiment, the anchoring device 20 further includes a Belleville-type spring washer that is threadedly connected to the stud 27 and is located between the nut 28 and the first-stage support plate 28, which allows the first-stage insulation block 11 to be elastically anchored to the second-stage sealing film 4.

[0119] Figure 5 Multiple embodiments of the spacer portions 50, 150, or 250 of the anchoring device 20 are shown, each spacer portion including: a central through-shell 51 for allowing the anchor rod 22 to pass through the spacer portion; an upper end surface 56 for receiving the lower plate 31 supported on the spacer portion; and a lower end surface 57 for supporting on the second-stage insulation block. The spacer portions 50, 150, or 250 are made of, for example, plywood to limit the thermal bridge. In the illustrated embodiment, the spacer portions 50, 150, or 250 preferably have the same rectangular cross-sectional shape as the lower plate 3. It can be formed by a small number of elongated portions with simple shapes that are rigidly assembled together, for example, by staples, bolts, and / or glue.

[0120] In a manner not shown, the central through-shell 51 is filled with thermal insulation around the anchor rod 22, such as glass wool, packing, expanded polystyrene, or polyurethane foam.

[0121] The spacer part 50 or 250 is formed by two planar rectangular plates 58 that form the main faces of the spacer part and two wedges 59 arranged between the two planar rectangular plates along the edges of the two planar rectangular plates. Thus, each of the four parts forms a wall of the central through-shell 51 having a square or rectangular cross-section.

[0122] The spacer part 150 is formed by four identical-profile elongated parts having a right-angled trapezoidal cross-section, and one inclined edge of the right-angled trapezoidal cross-section forms the corresponding wall of the central through-shell 51 having a rhombic cross-section. To limit the thermal bridge, longitudinal units are formed on either side of the central through-shell 51, and the longitudinal units are also filled with insulating material.

[0123] Figure 6 Another embodiment of the spacer part 350 is shown. The spacer part 350 is identical to the spacer part 250, except that each wedge 59 includes a blind hole 60, and each blind hole 60 is used to align with the fixing bolt 34 so that a part of the fixing bolt 34 can be received. In another variant not shown, the spacer part 50 may also include such blind holes 60. In the spacer part 150, the longitudinal units formed on either side of the central through-shell 51 may be only partially filled with insulating material, so that the insulating material and the longitudinal units together form a blind hole similar to the blind hole 60.

[0124] Figures 7 to 9 An embodiment of the thermal insulation block 451 that can be received in the central through-shell 51 is shown together. The thermal insulation block 451 has an external shape complementary to the external shape of the central through-shell 51, here a parallelepiped external shape. Here, the thermal insulation block 451 is made of thermally insulating polymer foam. The polymer foam can have a low density, that is, a density between 10 kg / m 3 and 60 kg / m 3 inclusive, and more particularly between 10 kg / m 3 and 30 kg / m 3 inclusive. The polymer foam can be polyurethane foam or melamine foam, especially melamine foam from the series of foams sold by BASF SE under the name The polymer foam can optionally be reinforced by fibers such as glass fibers.

[0125] It is also seen in Figures 7 to 9 that the thermal insulation block 451 includes through holes 452. The through holes 452 are used to receive the anchor rod 22 when the spacer part as described above is arranged below the clamping assembly 30. As Figure 9As can be seen, the through-hole 452 has a cross-section that widens from the upper end to the lower end of the anchor rod 22. In particular, this can be achieved by imparting to the through-hole 452 a frustoconical cross-section as Figure 9 shown. This widening of the cross-section in the direction towards the lower end of the anchor rod 22 allows for facilitating the installation of the spacer portion around the anchor rod 22, noting that this installation is carried out when the anchor rod 22 has been fixed to the support wall 2 via the bushing 23 and the nut 18. Additionally, this widening allows for providing a certain clearance in which the anchor rod 22 can move freely due to the ball-and-socket joint connection formed by the bushing 23. According to a variant not shown, the through-hole 452 can also have a cross-section that widens from the lower end to the upper end of the anchor rod 22. In particular, this can be achieved by imparting a frustoconical cross-section to the through-hole.

[0126] Figure 10 Another embodiment of the thermal insulation block 551 that can be received in the central through-housing 51 is shown. The thermal insulation block 551 has an external shape that is complementary to the external shape of the central through-housing 51, here a parallelepiped external shape. Here, the thermal insulation block 551 is made of glass wool. It can include two back-to-back sub-blocks 552 of glass wool. As described above, when the spacer portion is provided below the clamping assembly 30, the thermal insulation block 551 surrounds the anchor rod 22 (not shown in Figure 10 ). For this purpose, the thermal insulation block 551 can include, within its thickness, a notch 554 that extends parallel to the anchor rod 22. The notch 554 allows the anchor rod 22 to pass through the thermal insulation block 551 while allowing the glass wool to elastically recover to grip the anchor rod after the anchor rod 22 has passed through the thermal insulation block 551. The thermal insulation block 551 can also be made in the same way using cellulose or polyester fillers.

[0127] In Figure 10 it is also seen that a coating film 555 can be provided on two opposite faces of the thermal insulation block 551, more specifically, on the two larger faces of the thermal insulation block 551 that face the two larger faces of the central through-housing 51. The coating film 555 can be made of a glass fiber mat, kraft paper, or a polymer such as PVC. When the thermal insulation block 551 is inserted into the central through-housing 51, the coating film 555 allows for facilitating the sliding of the thermal insulation block 551 on the face of the central through-housing 51. Alternatively, there can be only one of the coating films 555 and / or a supplementary film (not shown) can be added on the faces of the thermal insulation block 551 that are not covered by the coating film 555.

[0128] In Figure 11 and Figure 12 another variant of the spacer portion together with the clamping assembly 30 has been shown, Figure 11 which is a cross-sectional view, Figure 12It is a partial perspective view seen from above the spacer portion. In this variant, a locking nut 37B, which is preferably not separated, is threadedly connected to the threaded lower end 35 of the fixing bolt 34. The locking nut 37B is received in a groove 660 in the spacer portion 650. Here, the spacer portion 650 is formed by two planar rectangular plates 58 that form the main faces of the spacer portion 650 and wedges 59 disposed between the two planar rectangular plates 58 along the edges of the two planar rectangular plates, like the spacer portion 250. A groove 660 is formed in each of the two wedges 59. The groove 660 includes two opposing faces, and two different faces of the locking nut 37B cooperate with the two opposing faces. This cooperation restricts the rotational movement of the fixing bolt 34 relative to the lower plate 31. In the embodiment shown in the drawings, the locking nut 37B is a square nut. However, the locking nut 37B can also be of another shape as long as it has two different faces that can cooperate with the two opposing faces of the groove 660. In particular, the locking nut 37B can have a hexagonal shape, and then two opposite faces of the hexagon cooperate with the two opposing faces of the groove 660. By rigidly connecting, for example, welding, especially spot welding, the bolt head 36 to the upper plate 32, the rotation of the fixing bolt 34 relative to the upper plate 32 is prevented.

[0129] The above-described spacer portions 50, 150, 250, 350, 650 can also be envisaged within the scope of the anchoring device without the spring element 39, whether or not they are provided with the thermal insulation blocks 451 or 551. More precisely, it is conceivable to provide the above-described spacer portions 50, 150, 250, 350, 650 with or without the thermal insulation blocks 451 or 551 in combination with the above-described anchoring rod 22 and the above-described clamping assembly 30, and the clamping assembly 30 does not have the spring element 39 and the platform 19 for receiving the spring element 39. Such a clamping assembly is described, for example, in WO-A-2014096600. Since there is no spring element 39, the upper plate 32 and the lower plate 31 are in Figure 2 the adjacent position shown on the right side, regardless of the pressure applied to the upper plate 32.

[0130] Example of dimensions

[0131] Due to the stiffness of the spring element 39, the clamping assembly 30 is in a separated position corresponding to the maximum spacing when the tank is empty and at ambient temperature - i.e., under the conditions applicable to its initial construction. In this state, the position of the upper plate 32 is adjusted to be aligned with the cover plate 15 to provide a uniform support surface for the secondary sealing film 4.

[0132] During the operation of the tank, after filling the tank with liquefied gas, thermal shrinkage and shrinkage and creep phenomena will occur in the secondary insulation barrier 3 under the hydrostatic load.

[0133] Thermal shrinkage is not the same in all materials, and the insulating polymer foam layer 16 tends to shrink more than the plywood that makes up the spacer 50 and the spacer block 33. In addition, the pressure loads differ depending on the location of the tank wall at the bottom, top or side. All walls receive at least the working pressure of the gas phase, which is, for example, 2 kPa or 5 kPa (20 or 50 mbar).

[0134] The stiffness of the spring element 39 can be determined so that, after cooling and at the working pressure of the gas phase, the elastic compression of the spring element 39 enables a supplementary lowering of the upper plate 32 which is greater than or equal to the additional contraction and creep of the second-stage insulating block 7 relative to the thermal contraction of the anchoring device 20. This additional contraction and creep of the second-stage insulating block 7 is, for example, about 1 mm at the working pressure of the gas phase. Thus, the upper plate 32 follows the level of the cover plate 15 and there is no risk that it creates a protruding area susceptible to shearing of the second-stage sealing membrane 6.

[0135] The stiffness and the size difference 40 of the spring element 39 can also be determined so that the clamping assembly 30 reaches an abutment position corresponding to the minimum spacing under the following conditions:

[0136] - Under static water load, if the first-stage insulation block below receives the maximum cargo pressure;

[0137] - or under dynamic loading, if the first-stage thermal insulation block below receives an impact pressure exceeding a predetermined nominal threshold due to sloshing of the cargo.

[0138] In all cases, the spring element 39 increases the flexibility of the anchoring device 20 and thus limits the risk of local formation of hard spots or protruding areas which could accelerate the ageing of the secondary sealing membrane 6 .

[0139] The total stiffness of the spring member, here the spring element 39, acting between the two plates is preferably less than the equivalent stiffness of the thermal insulation barrier next to the anchor at the operating temperature. In the embodiment shown, it is the insulating polymer foam layer 16 that controls the stiffness of the thermal insulation barrier. In one embodiment, the total stiffness of the spring element 39 is about 1880 N / mm, while the stiffness of the equivalent spring consisting of the insulating polymer foam block 16 with a cross section equal to that of the upper plate in the thickness direction of the tank wall is about 1920 N / mm, i.e. the thickness ratio is equal to 0.98. More generally, this ratio can be selected to be between 0.3 and 1.

[0140] The structure of the second-stage insulating block 7 has been described by way of example above. Additionally, in another embodiment, the second-stage insulating block 7 is liable to have another general structure, such as the structure described in document WO-A-2012127141. Then, the second-stage insulating block 7 is produced in the form of a box-shaped cross-section, including a bottom plate, a cover plate, and supporting webs that extend in the thickness direction of the tank wall 1 between the bottom plate and the cover plate and define a plurality of compartments filled with an insulating lining such as perlite, glass wool, or rock wool.

[0141] Another embodiment of the second-stage insulating block 107 is shown in Figure 14 In Figure 14 elements that are similar or identical to the elements in the previous figures have similar reference numerals increased by 100 and will not be described again. Here, the insulating polymer foam layer is divided into a lower layer 16b and an upper layer 16a separated by an intermediate plate 10, which is made of, for example, plywood and is pasted to the lower and upper layers. The length of the upper layer 16a is shorter than the length of the lower layer 16b, and edges 10a are exposed at the two longitudinal ends of the intermediate plate 10.

[0142] The rigid columns 17 extend in the thickness direction of the lower layer 16b between the intermediate plate 10 and the bottom plate 114 in recesses formed at the four corners of the lower layer 16b. The rigid columns 17 are partially vertically aligned with the edges 10a to withstand the clamping force of the anchoring device 20, the lower plate 31 of which can be directly applied to the edges 10a here. Other details of the second-stage insulating block 107 can be found in the publication WO-A-2014096600.

[0143] Now a variant of the anchoring device will be described with reference to Figure 15 and Figure 16 which is used to hold two second-stage blocks 107 adjacent to two second-stage insulating blocks 7 on the support wall 2. The transition from the second-stage insulating block 107 to the second-stage insulating block 7 can be used, in particular, as described in WO-A-2019077253, for example, near the edge of the support wall 2.

[0144] Therefore, in Figure 15 the second-stage insulating block 107 and the second-stage insulating block 7 are shown in a perspective view, and the other two second-stage insulating blocks are not shown to make the anchoring device 220 visible. Elements of the anchoring device 220 that are similar to the anchoring device 20 have the same reference numerals and will not be described again.

[0145] In Figure 15As seen in, on one side of the second-stage insulating block 107, the lower plate 31 is supported on the intermediate plate 10, while on one side of the second-stage insulating block 7, the lower plate 31 is supported on the spacer 280 received at the level of the corner region 54 via a spacer portion 750 to be described. Apparently, on one side of the second-stage insulating block 107, the anchoring device 220 must fill the space between the intermediate plate 10 and the bottom plate 114. However, since the lower plate 31 is supported on the intermediate plate 10, the portion of the anchoring device 220 that fills this space does not need to resist a force as high as the force transmitted by the spacer portion 750. Moreover, this space is occupied by a less dense spacer portion 760 to be described.

[0146] In summary, still referring to Figure 15 , below the lower plate 31, the anchoring device 220 includes a spacer assembly 700, which includes a spacer portion 750 located on one side of the insulating block 7 and a spacer portion 760 located on one side of the insulating block 107.

[0147] In Figure 16 , only the spacer assembly 700 is shown in a perspective view.

[0148] As can be seen in this figure, the spacer portion 750 has an upper end surface 756 on which the lower plate 31 is supported and a lower end 757 for supporting on the spacer 280 on the second-stage insulating block 7. The spacer portion 750 is made of plywood, for example, to limit the thermal bridge.

[0149] The spacer portion 750 is formed by two planar rectangular plates 758 that form the main faces of the spacer portion 750 and wedges 759 disposed between the two planar rectangular plates 758 along the edges of the two planar rectangular plates. In Figure 16 it is also seen that the wedge 759 may include a blind hole 751 for aligning with one of the fixing bolts 34 of the clamping assembly 30 so as to be able to receive a part of the fixing bolt 34.

[0150] For its part, the spacer portion 760 includes a central portion 761, which includes a through hole 762 through which the anchor rod 22 passes. The lower plate 31 can be supported on the upper surface 766 of this central portion 761.

[0151] In addition, a tongue 765 projects from the central portion 761 towards the spacer portion 750 and is received in a housing of a complementary portion formed by the plate 758 and the wedge 759 of the spacer portion 750. The tongue 765 can be pushed into this housing or glued and / or nailed and / or screwed to the plate 758.

[0152] In addition, the spacer portion 760 may include a flange 770 projecting from the central portion 761 in a direction away from the spacer portion 750. As seen fromFigure 15 As can be seen, the flange 770 can also be supported on the opposing lateral surfaces of the insulating block 107.

[0153] As previously mentioned, the space occupied by the spacer portion 760 does not need to withstand as high a force as the force transmitted by the spacer portion 750. In addition, the spacer portion 760 is made of a thermally insulating polymer foam to limit thermal bridging. The polymer foam can have a low density, that is, a density between 10 kg / m 3 to 60 kg / m 3 including the end values, and more particularly between 10 kg / m 3 to 30 kg / m 3 including the end values. The polymer foam can be polyurethane foam or melamine foam, particularly melamine foam from the series of foams sold by BASF SE under the name The polymer foam can optionally be reinforced by fibers such as glass fibers. As an alternative to the polymer foam, polystyrene can also be used as insulation.

[0154] As in the case of the spacer portions 50, 150, 250, 350, 650 described above, it is conceivable to provide the spacer assembly 700 in combination with the anchor rod 22 described above and the clamping assembly 30 described above, where the clamping assembly 30 does not have the spring element 39 and the platform 19 for receiving the spring element 39. Such a clamping assembly is described, for example, in WO-A-2014096600. Since there is no spring element 39, the upper plate 32 and the lower plate 31 are in Figure 2 the adjacent position shown on the right, regardless of the pressure applied to the upper plate 32.

[0155] The first-stage insulating block 11 can be produced in various ways, for example, in the form of an insulating polymer foam layer sandwiched between a bottom plate and a cover plate, like the second-stage insulating block 7.

[0156] Then, the bottom plate includes a groove for receiving the raised edge of the column plate 8 of the second-stage sealing film 4. The cover plate also includes a groove for receiving the welding support.

[0157] The structure of the first-stage insulating plate member 11 has been described above by way of example. Additionally, in another embodiment, the first-stage insulating plate member 22 can easily have another general structure, such as the structure described in the document WO-A-2012127141.

[0158] The techniques described above for producing tank walls with a single or two sealing membranes can also be used in different types of containers, for example, for constructing double-membrane tanks for liquefied natural gas (LNG) in onshore facilities or in floating structures such as methane tankers or other ships.

[0159] Referring Figure 17 , a cross-sectional view of a methane tanker 70 shows a sealed and insulated tank 71 with a generally prismatic shape installed in the double hull 72 of the ship. The walls of the tank 71 include a first-stage sealing barrier for contacting the LNG contained in the tank, a second-stage sealing barrier arranged between the first-stage sealing barrier and the double hull 72 of the ship, and two insulating barriers respectively arranged between the first-stage sealing barrier and the second-stage sealing barrier and between the second-stage sealing barrier and the double hull 72.

[0160] In a manner known per se, the loading / unloading pipeline 73 provided on the upper deck of the ship can be connected to an offshore terminal or a port terminal by means of a suitable connector for transferring LNG cargo from or to the tank 71.

[0161] Figure 17 An example of an offshore terminal is shown, which includes a loading and unloading station 75, a subsea pipeline 76, and an onshore facility 77. The loading and unloading station 75 is a fixed offshore facility, including a movable arm 74 and a tower 78 supporting the movable arm 74. The movable arm 74 carries a bundle of insulated flexible pipes 79 that can be connected to the loading / unloading pipeline 73. The orientable movable arm 74 is suitable for all methane tanker loading scales. Connecting pipes (not shown) extend inside the tower 78. The loading and unloading station 75 enables the loading of the methane tanker 70 from the onshore facility 77 and the unloading from the methane tanker to the onshore facility. The facility includes: a liquefied gas storage tank 80; and a connecting pipe 81 connected to the loading or unloading station 75 through the subsea pipeline 76. The subsea pipeline 76 enables the transfer of liquefied gas between the loading or unloading station 75 and the onshore facility 77 over a large distance, for example, 5 km, which enables the methane tanker 70 to be kept at a large distance from the coast during loading and unloading operations.

[0162] To generate the pressure necessary for transferring the liquefied gas, pumps on the ship 70 and / or pumps installed in the onshore facility 77 and / or pumps installed in the loading and unloading station 75 are used.

[0163] Although the invention has been described in connection with several specific embodiments, it is obvious that the invention is in no way limited to these embodiments and the invention includes all technical equivalents of the described means and their combinations, if these fall within the scope of the invention defined by the claims.

[0164] The use of the verb "comprise" or "include" and their cognate forms does not exclude the presence of other elements or steps in addition to those elements or steps recited in the claims.

[0165] In the claims, any reference signs in parentheses shall not be construed as limiting the claim.

Claims

1. A sealed thermally insulated tank for storing a fluid, the tank comprising a support wall, anchoring means (20) fixed to the support wall (2), and a tank wall (1) anchored to the support wall by means of the anchoring means, the tank wall (1) comprising, in the thickness direction, from the outside to the inside of the tank, a thermal insulation barrier (3) and a sealing film (4) resting against the thermal insulation barrier (3). wherein, The thermal insulation barrier (3) comprises parallelepiped-shaped insulation blocks (7; 107) juxtaposed on the support wall (2), each of the insulation blocks (7; 107) comprising a cover plate (15; 115) defining a support surface for the sealing film (4); wherein at least one of the anchoring means (20; 220) comprises: - a clamping assembly (30) comprising a lower plate (31), an upper plate (32) parallel to the lower plate, connection members (34) connecting the lower plate to the upper plate, and a spacer member disposed between the lower plate and the upper plate, the spacer member comprising a rigid abutment portion (33), the rigid abutment portion defining a minimum spacing between the lower plate and the upper plate at an abutment position where the lower plate and the upper plate abut against the abutment portion, - an anchoring rod (22) protruding from the clamping assembly perpendicular to the lower plate (31), the anchoring rod comprising a lower end and an upper end, the lower end being fixed to the support wall (2) between adjacent insulation blocks (7; 107), the upper end being opposite to the lower end and coupled to the lower plate (31) so as to be able to apply a traction on the lower plate in the direction of the lower end, and - a spacer portion (50, 150, 250, 350, 650; 700) disposed below the lower plate and comprising a central housing (51; 762) through which the anchoring rod (22) passes, the spacer portion comprising an upper surface (56; 756) and a lower surface (57; 757), the upper surface being configured to support against the lower plate (31) of the clamping assembly (30), wherein a plurality of adjacent insulation blocks (7) of the anchoring rod (22) comprise a bottom plate (14) parallel to and spaced from the cover plate (15) and a fiber-reinforced polymer foam block (16) disposed between the cover plate and the bottom plate (14), the cover plate (15) and the polymer foam block (16) comprising recesses (53) exposing corner portions (54) of the bottom plate (14), and wherein the lower surface (57; 757) of the spacer portion (50, 150, 250, 350, 650; 700) supports on the corner portions (54) of the plurality of insulation blocks (7), and the lower plate (31) of the clamping assembly (30) cooperates with the corner portions (54) of the plurality of insulation blocks (7) via the spacer portion (50, 150, 250, 350, 650; 700) to clamp the plurality of insulation blocks (7) in the direction of the support wall (2) without applying any clamping action on the polymer foam block (16).

2. The tank according to claim 1, wherein, The central housing (51) is filled with thermal insulation around the anchoring rod (22).

3. The tank according to claim 1 or 2, wherein, The spacer portion (150) is formed by four elongate portions of the same profile, the inclined planes on the elongate portions forming respective walls of the central housing (51), and the elongate portions being rigidly assembled to each other.

4. The tank according to claim 1, wherein, The spacer part (50, 250, 350, 650) is formed by two opposing plates (58) and two wedges (59) disposed between the two opposing plates, and each of the two wedges and the two plates forms a respective wall of the central housing (51).

5. The tank according to claim 2, wherein, The spacer part (50, 250, 350, 650) is formed by two opposing plates (58) and two wedges (59) disposed between the two opposing plates, and each of the two wedges and the two plates forms a respective wall of the central housing (51).

6. The tank according to claim 5, wherein, The thermal insulation includes a glass wool block (551) around the anchor rod (22).

7. The tank according to claim 6, wherein, The glass wool block (551) includes a notch (554) within its thickness for receiving the anchor rod (22).

8. The tank according to claim 6 or 7, wherein, The glass wool block (551) includes at least one sheet (555) of glass fiber mat, kraft paper, or polymer, which is disposed between the glass wool block and an opposing wall of the central housing (51).

9. The tank according to claim 5, wherein, The thermal insulation includes a polymer foam block (451), which includes a through-hole (452) for receiving the anchor rod (22).

10. The tank according to claim 9, wherein, The through-hole (452) has a cross-section that widens from one of the upper and lower ends of the anchor rod (22) to the other of the upper and lower ends of the anchor rod (22).

11. The tank according to claim 1, wherein, The spacer part is a spacer assembly (700), which includes a first spacer part (750) and a second spacer part (760) rigidly attached to the first spacer part. The first spacer part (750) includes the lower surface (757) and the upper surface (756) configured to bear against the lower plate (31) of the clamping assembly (30). The second spacer part (760) is made of polymer foam and includes the central housing (762) through which the anchor rod (22) passes.

12. The tank according to claim 11, wherein, A plurality of adjacent insulation blocks (107) of the anchor rod (22) sequentially include: an intermediate plate (10) and a bottom plate (114) that are both parallel to the cover plate (115) and spaced apart from each other, and two fiber-reinforced polymer foam blocks (16a, 16b) respectively disposed between the cover plate (115) and the intermediate plate (10) and between the intermediate plate (10) and the bottom plate (114), and wherein the lower plate (31) of the anchoring device (220) directly mates with the intermediate plate (10) at the level of the corner region.

13. The tank according to any one of claims 1 to 12, wherein, The thermal insulation barrier is a second-stage thermal insulation barrier (3), the insulation block is a second-stage insulation block (7), the sealing film is a second-stage sealing film (4), and the tank wall further includes a first-stage thermal insulation barrier (5) resting against the second-stage sealing film (4) and a first-stage sealing film (6) resting against the first-stage thermal insulation barrier (5) and for contacting the fluid contained in the tank; the first-stage thermal insulation barrier (5) includes first-stage insulation blocks (11), and each of the first-stage insulation blocks is stacked on one of the second-stage insulation blocks (7). Wherein, the clamping assembly (30) forms a second-stage clamping member for cooperating with the second-stage thermal insulation barrier, the upper plate (32) includes a central boring (47), a stud (27) protruding from the clamping assembly is screwed into the central boring on a side opposite to the anchor rod, the stud (27) carries a first-stage clamping member (28) for cooperating with the first-stage thermal insulation barrier (5), and wherein, the stud (27) passes through the second-stage sealing film (4) in a sealed manner, and the first-stage clamping member abuts against a plurality of first-stage insulation blocks (11) stacked on the plurality of second-stage insulation blocks in the direction of the support wall (2) to hold the plurality of first-stage insulation blocks in the direction towards the support wall (2).

14. A ship (70) for transporting fluids, the ship comprising a double hull (72) and a tank (71) as claimed in any one of claims 1 to 13 provided in the double hull (72).

15. A transfer system for fluids, the system comprising: A ship (70) according to claim 14; insulated pipelines (73, 79, 76, 81) arranged to connect a tank (71) installed in the hull of the ship to a floating or onshore storage facility (77); and pumps for driving fluid from the floating or onshore storage facility through the insulated pipelines to the tank of the ship, or from the tank of the ship through the insulated pipelines to the floating or onshore storage facility.

16. A method of loading or unloading the ship (70) as claimed in claim 14, wherein, Routing fluid from a floating or onshore storage facility (77) through insulated pipelines (73, 79, 76, 81) to the tank (71) of the ship or from the tank of the ship through the insulated pipelines to the floating or onshore storage facility.

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