Sealed and thermally insulated tank

Abstract

The present invention relates to a sealed and thermally insulated tank wall (1) for storing liquefied gas, the wall comprising at least one thermally insulating barrier and a sealing membrane, the sealing membrane being anchored to the thermally insulating barrier and for contact with the liquefied gas, the thermally insulating barrier comprising a first insulating panel and a second insulating panel disposed along a first edge of the first insulating panel, the first insulating panel and the second insulating panel being respectively provided with at least one first anchoring element and at least one second anchoring element, and the sealing membrane being welded to the anchoring element; the sealing membrane comprising corrugated portions separated from each other by planar portions, at least one of the planar portions being arranged to span the first insulating panel and the second insulating panel, and at least one of the planar portions being welded to both the first anchoring element and the second anchoring element.

Description

Technical Field

[0001] This invention relates to the field of sealed and thermally insulated tanks for storing and / or transporting liquefied gases, such as tanks for transporting liquefied petroleum gas (also known as LPG) having a temperature, for example, between -50°C and 0°C, or tanks for transporting liquefied natural gas (LNG) at atmospheric pressure and at about -163°C.

[0002] These tanks can be installed on land or on floating structures. In the case of floating structures, the tanks can be used for transporting liquefied gases or for receiving liquefied gases used as fuel to propel the floating structure. Background Technology

[0003] As is known from the prior art, a sealed and thermally insulated tank includes a tank wall held on a support structure, which, in the thickness direction of the tank from the outside to the inside, comprises: a secondary thermal insulation barrier held on the support structure, a secondary sealing membrane held on the secondary thermal insulation barrier, a primary thermal insulation barrier held on the secondary sealing membrane, and a corrugated primary sealing membrane held on the primary thermal insulation barrier. Such a sealed and thermally insulated tank can be particularly used for the transport of liquefied gases, such as liquefied natural gas (LNG), especially on floating structures such as ships.

[0004] It is known in practice that primary sealing membranes are produced by assembling multiple corrugated sheets, the corrugations of which advantageously extend perpendicularly to each other. The corrugations give the primary sealing membrane a degree of flexibility that allows it to deform under the influence of thermal and mechanical stresses, and specifically, this deformation is generated by the liquefied gas stored within the tank and is associated with the deformation of the supporting structure. The primary sealing membrane is anchored to the insulating panels of a primary thermal insulation barrier. For this purpose, each sheet is arranged to span multiple insulating panels of the primary thermal insulation barrier. Furthermore, the sheets are welded to each other along their edges and also to anchoring elements fixed to the insulating panels along their edges. More specifically, the sheets are welded to anchoring elements arranged along the edges of the sheets on either side of each corrugation.

[0005] The applicant company has observed that in the aforementioned type of tank, the corrugated portions of the primary sealing membrane are subjected to uneven stress. Specifically, because the primary thermal insulation barrier is discontinuous—that is, it consists of insulating panels placed side-by-side—it exhibits uneven stress when the support structure deforms and / or under the influence of thermal and mechanical stresses generated by the liquefied gas stored in the tank. Therefore, the applicant company has observed that the corrugated portions located in the area spanning the first anchoring element fixed to the first insulating panel and the second anchoring element fixed to the second insulating panel experience higher stresses than other corrugated portions. It is now important to ensure that the stress is distributed as evenly as possible among the corrugated portions of the primary sealing membrane, particularly to optimize the lifespan of the primary sealing membrane. Summary of the Invention

[0006] One idea behind this invention is to propose a sealed and thermally insulated container in which the stress experienced by the primary sealing membrane is more evenly distributed between the corrugations of the primary sealing membrane.

[0007] According to one embodiment, the present invention relates to a sealed and thermally insulated tank wall for storing liquefied gas, the wall comprising at least one thermally insulating barrier and a sealing membrane, the sealing membrane being anchored to the thermally insulating barrier and for contact with the liquefied gas, the thermally insulating barrier comprising a first insulating panel and a second insulating panel disposed along a first edge of the first insulating panel, the first insulating panel and the second insulating panel being respectively provided with at least one first anchoring element and at least one second anchoring element, the sealing membrane being welded to the anchoring elements; the sealing membrane comprising corrugated portions separated from each other by flat portions, wherein at least one of the flat portions is arranged to span the first insulating panel and the second insulating panel, and at least one of the flat portions is welded to the first anchoring element on one side and to the second anchoring element on the other side.

[0008] Therefore, the arrangement of the sealing membrane across the planar portion of adjacent insulating panels performs the function of mechanically connecting the insulating panels. This prevents the insulating panels from shifting and separates, and helps to distribute the deformation of the load-bearing structure more evenly across the primary thermal insulation barrier. In fact, the behavior of the assembly including the thermal insulation barrier and the sealing membrane is determined here by the fact that the insulating panels typically have a lower stiffness than the sealing membrane. Therefore, it is the deformation of the sealing membrane that controls the deformation of the insulating panels. This allows for a more uniform application of stress to the corrugated portion of the sealing membrane.

[0009] According to the implementation method, such a tank wall may include one or more of the following features.

[0010] According to one embodiment, the stiffness of the first and second insulating panels is less than the stiffness of the planar portion of the sealing film. This ensures that the deformation of the thermal insulation barrier is determined by the deformation of the sealing film. For example, the stiffness of the first and second insulating panels is three times lower than the stiffness of the planar portion of the sealing film.

[0011] According to one embodiment, the first anchoring element and the second anchoring element are arranged such that the central portions of the first anchoring element and the second anchoring element are spaced apart by a distance between 8 cm and 25 cm, and preferably between 10 cm and 20 cm.

[0012] According to one embodiment, the first anchoring element is arranged at least along a first edge of the first insulating panel, while the second anchoring element is arranged at least along an edge of the second panel adjacent to the first edge of the first insulating panel.

[0013] According to one embodiment, the sealing film includes a first corrugated portion extending parallel to a first direction and a second corrugated portion extending parallel to a second direction, wherein the first direction is perpendicular to the second direction.

[0014] According to one implementation, the corrugations are continuous, that is, uninterrupted.

[0015] According to one embodiment, the first insulating panel and the second insulating panel have a parallelepiped shape, and each of the first insulating panel and the second insulating panel has two opposite edges parallel to a first direction and two opposite edges parallel to a second direction.

[0016] According to one embodiment, the first insulating panel and the second insulating panel are respectively provided with a plurality of first anchoring elements and a plurality of second anchoring elements, and a plurality of planar portions are arranged to span the first insulating panel and the second insulating panel, and each of the plurality of planar portions is welded to one of the first anchoring elements and one of the second anchoring elements.

[0017] According to one embodiment, the sealing membrane is welded to at least one first anchoring element and at least one second anchoring element by plug welding or through welding.

[0018] According to one embodiment, at least one first anchoring element and at least one second anchoring element each comprise a metal plate fixed in a perforated recess formed in one of the first and second insulating panels.

[0019] According to one embodiment, the sealing membrane includes a plurality of corrugated metal sheets, each corrugated metal sheet having an edge that is lap-welded to the edge of an adjacent corrugated metal sheet.

[0020] According to one embodiment, at least one planar portion of the first and second insulating panels, which is arranged to span across the first and second insulating panels and welded to the first and second anchoring elements, is made as a single piece, that is, it is made of a single corrugated metal sheet.

[0021] According to one embodiment, a planar portion arranged to span a first insulating panel and a second insulating panel and welded to a first anchoring element and a second anchoring element belongs to a first edge portion of a corrugated metal sheet; the first edge portion is superimposed by second edge portions of adjacent corrugated metal sheets, the first edge portion is welded to a first anchoring member by a first plug weld and to a second anchoring member by a second plug weld, the second edge portion is superimposed with the second plug weld and at least a portion of the first plug weld, and is sealed corner welded to the first edge portion.

[0022] According to one embodiment, the planar portion arranged to span the first insulating panel and the second insulating panel and welded to the first anchoring element and the second anchoring element is made of the first edge portion and the second edge portion of two adjacent corrugated metal sheets welded together.

[0023] According to one embodiment, a first edge portion is used to be stacked on a second edge portion, the first edge portion being welded to a first anchoring member by means of a weld portion, such as a plug weld portion, the second edge portion being welded to a second anchoring member, at least partially overlapping the weld portion, and the second edge portion being corner-welded to the first edge portion in a sealing manner.

[0024] According to one embodiment, the first insulating panel and the second insulating panel each have a heat protection element facing the edge of the corrugated metal sheet.

[0025] According to one embodiment, the thermal protection element is formed in the form of a composite film or aluminum sheet comprising at least one aluminum foil associated with at least one glass fiber pad.

[0026] According to one embodiment, a thermal insulation barrier includes: a third insulating panel arranged along a second edge of a first insulating panel, a fourth insulating panel arranged along a third edge of the first insulating panel, and a fifth insulating panel arranged along a fourth edge of the first insulating panel, the third, fourth, and fifth insulating panels being respectively provided with a third anchoring element, a fourth anchoring element, and a fifth anchoring element; and a sealing film including: a planar portion arranged to span the first and third insulating panels, wherein each of the first and third insulating panels is welded to a first anchoring element on one side and to a third anchoring element on the other side; a planar portion arranged to span the first and fourth insulating panels, wherein each of the first and fourth insulating panels is welded to a first anchoring element on one side and to a fourth anchoring element on the other side; and a planar portion arranged to span the first and fifth insulating panels, wherein each of the first and fifth insulating panels is welded to a first anchoring element on one side and to a fifth anchoring element on the other side.

[0027] According to one embodiment, the first anchoring element is arranged at least along a first edge of the first insulating panel, while the second anchoring element is arranged at least along an edge of the second panel adjacent to the first edge of the first insulating panel.

[0028] According to one embodiment, the first anchoring element is arranged along the first edge, second edge, third edge and fourth edge of the first insulating panel.

[0029] According to one embodiment, the anchoring elements of each insulating panel are arranged along the four edges of the insulating panel.

[0030] According to one embodiment, the first edge and the second edge of the first insulating panel are continuous, the wall includes a sixth panel arranged along the edge of the second insulating panel and along the edge of the third insulating panel, and the sixth panel is equipped with a sixth anchoring element.

[0031] According to one embodiment, one of the planar portions is arranged to span the first insulating panel, the second insulating panel, the third insulating panel, and the sixth insulating panel, and is fixed to a first anchoring element of the first anchoring element, a second anchoring element of the second anchoring element, a third anchoring element of the third anchoring element, and a sixth anchoring element of the sixth anchoring element.

[0032] According to one embodiment, the first insulating panel and the second insulating panel have relaxation grooves for corrugated portions facing the sealing film, and more particularly each of the corrugated portions facing the sealing film opposite to the first insulating panel and the second insulating panel.

[0033] According to one embodiment, at least one first anchoring element and at least one second anchoring element are respectively placed on the edge portion of the first insulating panel and the edge portion of the second insulating panel, the edge portion of the first insulating panel and the edge portion of the second insulating panel being defined by at least one of the relaxation grooves of the first insulating panel and the second insulating panel.

[0034] According to one embodiment, each relaxation groove adjacent to one of the edges of the first panel or the second panel defines a plurality of edge regions with a relaxation groove perpendicular to it, and each edge region is equipped with a first anchoring element or a second anchoring element.

[0035] According to one embodiment, the sealing membrane is a primary sealing membrane, the thermal insulation barrier is a primary thermal insulation barrier, and the wall further includes a secondary thermal insulation barrier that maintains the abutment support structure, and a secondary sealing membrane fixed to the secondary thermal insulation barrier and disposed between the secondary thermal insulation barrier and the primary thermal insulation barrier.

[0036] According to one embodiment, the present invention relates to a sealed and thermally insulated tank having the aforementioned wall.

[0037] The tank according to one embodiment of the above-described embodiments can form part of an onshore storage facility, such as for storing LNG, or can be installed in a nearshore or offshore floating structure, particularly an ethane or methane tank, a floating storage and regasification unit (FSRU), a floating production storage and offloading (FPSO) unit, etc. In the case of a floating structure, the tank can be used to receive liquefied natural gas as fuel for propelling the floating structure.

[0038] According to one embodiment, the present invention provides a vessel for transporting fluids, the vessel having: a hull, such as a double hull; and the aforementioned tank disposed in the hull.

[0039] According to one embodiment, the present invention also provides a method for loading or unloading such a vessel, wherein fluid is transported from a floating or land-based storage facility to a tank on the vessel, or from a tank on the vessel to a floating or land-based storage facility, via insulated pipelines.

[0040] According to one embodiment, the present invention also provides a fluid transfer system, the system comprising: the aforementioned vessel; an insulated pipeline arranged to connect a tank installed in the hull of the vessel to a floating or onshore storage facility; and a pump for driving fluid from the floating or onshore storage facility to the tank of the vessel, or from the tank of the vessel to the floating or onshore storage facility, via the insulated pipeline. Attached Figure Description

[0041] The invention will be better understood during the following description of several specific embodiments with reference to the accompanying drawings, which are given for illustrative purposes only and not for limitation, and other objects, details, features, and advantages of the invention will become more apparent.

[0042] [ Figure 1 ] Figure 1 This is a schematic diagram of the cross-section of the multi-layered structure of the tank wall.

[0043] [ Figure 2 ] Figure 2 This is a partial sectional view of the tank wall.

[0044] [ Figure 3 ] Figure 3 It is a three-dimensional view of the corrugated metal sheet of the primary sealing membrane.

[0045] [ Figure 4 ] Figure 4 This is a partial view of the primary thermal insulation barrier from above.

[0046] [ Figure 5 ] Figure 5 This is a partial view of a cross-section of a primary anchoring device according to one embodiment.

[0047] [ Figure 6 ] Figure 6 It is a cross-sectional schematic diagram of a ship having tanks for storing liquefied natural gas and terminals for loading / unloading from the tanks.

[0048] [ Figure 7 ] Figure 7 It is shown in Figures 2 to 4 A schematic cross-sectional view of the overlapping edges of two adjacent corrugated metal sheets in the embodiment.

[0049] [ Figure 8 ] Figure 8 According to another embodiment, and Figure 2 A partial cross-sectional view of a tank wall similar to the tank wall.

[0050] [ Figure 9 ] Figure 9 It shows Figure 8A schematic cross-sectional view of the overlapping edges of two adjacent corrugated metal sheets in the embodiment.

[0051] [ Figure 10 ] Figure 10 It shows according to Figure 8 A schematic cross-sectional view of the overlapping edges of two adjacent corrugated metal sheets in a variant of the implementation.

[0052] [ Figure 11 ] Figure 11 It shows according to Figure 8 A schematic cross-sectional view of the overlapping edges of two adjacent corrugated metal sheets in another variant of the implementation.

[0053] [ Figure 12 ] Figure 12 This is a partial cross-sectional view of the tank wall according to another embodiment variant.

[0054] [ Figure 13 ] Figure 13 The can wall is in accordance with yet another embodiment variant. Figure 2 and Figure 8 A partial sectional view similar to the view.

[0055] [ Figure 14 ] Figure 14 It is based on Figure 13 Detailed cross-sectional view of the anchoring element in the implementation method.

[0056] [ Figure 15 ] Figure 15 This is a perspective view of an insulating panel according to another embodiment variant.

[0057] [ Figure 16 ] Figure 16 It shows the method of being fixed to Figure 14 Anchoring elements for insulating panels. Detailed Implementation

[0058] By convention, the terms “external” and “internal” are used to define the relative position of one element with respect to the exterior and interior of a container.

[0059] Figure 1The diagram schematically illustrates the multi-layered structure of the wall 1 of a sealed and thermally insulated tank for storing liquefied gas. Each wall 1, extending from the outside of the tank toward the inside, includes: a secondary thermal insulation barrier 2 comprising a secondary panel 3 anchored to a support structure 4; a secondary sealing membrane 5 resting against the secondary thermal insulation barrier 2; a primary thermal insulation barrier 6 comprising a primary panel 7 resting against the secondary sealing membrane 5 and anchored to the secondary panel 3; and a primary sealing membrane 8 resting against the primary thermal insulation barrier 6 and for contacting the liquefied gas contained within the tank.

[0060] The support structure 4 can be specifically formed from the hull of a ship or a double hull. The support structure 4 includes multiple walls that define the overall shape of the tank, typically a polyhedral shape.

[0061] Combination Figure 2 As can be seen, the secondary thermal insulation barrier 2 includes a plurality of secondary panels 3. The secondary panels 3 are anchored to the support structure 4 by means of secondary anchoring devices (not shown). The secondary panels 3 have an overall parallelepiped shape and are arranged in mutually parallel secondary rows. For example, in the illustrated embodiment, the secondary panel 3 has an insulating polymer foam layer 9 sandwiched between an outer sheet 10 and an inner sheet 11. The outer sheet 10 and the inner sheet 11 are, for example, made of plywood and bonded to the insulating polymer foam layer 9. The insulating polymer foam may in particular be polyurethane-based foam, and optionally reinforced glass fiber. The structure of the secondary panel 3 has been described above by way of example. Furthermore, in another embodiment, the secondary panel 3 can adopt another overall structure, such as the structure described in document WO2012 / 127141. In another embodiment, the secondary thermal insulation barrier 2 includes secondary panels 3 having at least two different types of structures, such as the two structures described above, depending on the location of the secondary panel within the tank.

[0062] Figure 2 The secondary sealing membrane 5 shown in the middle section includes a continuous layer of metal plates 12, each plate having two parallel upturned edges. The plates 12 are welded to parallel welded supports via these upturned edges, the supports being accommodated in grooves formed in the inner sheet 11 of the secondary panel 3. The plates 12 are, for example, made of... Made of: an alloy of iron and nickel, the coefficient of thermal expansion of which is typically 1.2 x 10⁻⁶. -6 K -1 With 2x10 -6 K -1 Between. Iron and manganese alloys can also be used, with a coefficient of thermal expansion typically around 7 x 10⁻⁶. -6 K-1 Up to 9x10 -6 K -1 In another embodiment, the metal film has corrugated portions, and the metal film may, for example, be made of the same alloy as the column plate.

[0063] In addition, the primary thermal insulation barrier 6 includes a plurality of primary panels 7, which are anchored to the secondary thermal insulation barrier 2 by means of primary anchoring devices, as described later. Figure 5 As described. The primary panel 7 has an overall shape of a parallelepiped and is arranged in rows that are parallel to each other.

[0064] The primary panel 7 can have a multi-layered structure similar to that of the secondary panel 3. Therefore, according to the illustrated embodiment, the primary panel 7 sequentially includes, in the thickness direction of the wall 1, an outer sheet 13 made of, for example, plywood, an insulating polymer foam layer 14, and an inner sheet 15 made of, for example, plywood. The insulating polymer foam layer 14 is, for example, based on polyurethane foam, and optionally reinforced with glass fiber. The structure of the primary panel 7 has been described above by way of example.

[0065] like Figure 2 As shown, the outer sheet 13 of the primary panel 7 has a groove for receiving the upturned edge of the column plate 12 of the secondary sealing film 5.

[0066] Furthermore, the primary sealing membrane 8 is obtained by assembling multiple corrugated metal sheets 16, wherein one of the corrugated metal sheets is in Figure 3 As shown in the diagram. The corrugated metal sheet 16 is made, for example, of stainless steel or aluminum. The primary sealing film 8 has a thickness between 1 mm and 2 mm, and preferably between 1.2 mm and 1.8 mm. Each corrugated metal sheet 16 has two sets of mutually perpendicular corrugated portions 17, 18. The corrugated portions 17, 18 are separated from each other by rectangular, and advantageously square, planar portions 19. The corrugated metal sheet 16 is rectangular and preferably has the following width and length dimensions: the width and length dimensions are integer multiples of the spacing between the corrugated portions and also integer multiples of the size of the primary panel 7. In this embodiment, the corrugated portions 17, 18 are continuous and intersect each other. In variant embodiments not described, each of the corrugated portions 17, 18 has corrugated portions with scattered planar portions. The corrugated portions are therefore discontinuous. Advantageously, the corrugated portions do not intersect each other.

[0067] like Figure 2As shown, the corrugated metal sheet 16 of the primary sealing membrane 8 is welded to the anchoring element 20. According to one embodiment, the anchoring element 20 is a metal plate housed in a perforated recess in the inner sheet 15 and secured to the inner sheet by means of fasteners such as rivets or screws. The corrugated metal sheet 16 is arranged to span a plurality of primary panels 7, and the corrugated metal sheet 16 is arranged such that the edges of the corrugated metal sheet and the corrugations 17, 18 of the corrugated metal sheet are oriented parallel or perpendicular to the primary panels 7.

[0068] The corrugated metal sheet 16 of the primary sealing membrane 8 is anchored along the edge of each primary panel in the primary panels 7. Each planar portion 19 of the primary sealing membrane 8 spanning at least two primary panels 7 is fixed on one hand to an anchoring element 20 fixed to one of the primary panels 7, and on the other hand to another anchoring element 20 fixed to another primary panel in an adjacent primary panel 7. Advantageously, the two anchoring elements 20, for welding one planar portion of the planar portion 19 to two adjacent primary panels 7 respectively, are arranged such that the central portions of the two anchoring elements are spaced apart by a distance between 8 cm and 25 cm, and preferably by a distance between 10 cm and 20 cm. This allows for the limitation of the stress level that may be applied to the welded portion of the corrugated metal sheet 16 at the anchoring element 20, especially due to the deformation of the hull due to expansion or swaying.

[0069] Therefore, in this embodiment, the anchoring of the primary sealing membrane 8 is not achieved at the edge of the corrugated metal sheet 16, but rather in the planar portions corresponding to the edges of each primary panel in the primary panels 7. The planar portions 19 are arranged to span at least two adjacent primary panels 7, thereby performing the function of mechanically connecting the primary panels 7. This prevents the primary panels 7 from moving apart and helps to distribute the deformation of the load-bearing structure 4 more evenly on the primary thermal insulation barrier 6. It will also be observed that certain planar portions 19 spanning the four corner regions of the four adjacent primary main panels 7 are anchored to the anchoring elements 20 belonging to each of the four adjacent primary panels 7.

[0070] In addition, such as Figure 2 As shown, each primary panel 7 includes a relaxation groove 21, each relaxation groove 21 extending toward a corresponding corrugation 17, 18 of the primary sealing film 8. These relaxation grooves 21 can take full advantage of the corrugations 17, 18 because they allow the primary sealing film 8 to deform without applying excessive mechanical stress to the primary panel 7.

[0071] In the illustrated embodiment, each primary panel 7 faces three corrugated portions 17 extending parallel to a first direction and three corrugated portions 18 extending parallel to a second direction perpendicular to the first direction. Furthermore, each primary panel 7 includes: three relaxation grooves 21 extending parallel to the first direction, each facing one of the corrugated portions 17; and three relaxation grooves 21 extending parallel to the second direction, each facing one of the corrugated portions 17 and 18. Therefore, the relaxation grooves 21 are separated by a spacing corresponding to the spacing between the corrugated portions 17 and 18 parallel to the relaxation grooves 21. However, each relaxation groove 21 adjacent to one edge of the primary panel 7 is spaced apart from the edge by a distance substantially corresponding to half the spacing between the corrugated portions parallel to the relaxation grooves. Each relaxation groove 21 adjacent to one edge of the primary panel 7 defines multiple edge regions with a relaxation groove perpendicular to it, each of the multiple edge regions being equipped with an anchoring element 20.

[0072] The corrugated metal sheet 16 of the primary sealing membrane 8 is fixed to the anchoring element 20 by welding.

[0073] according to Figure 2 In the first embodiment shown, the corrugated metal sheet 16 is anchored to the anchoring element 20 using a plug weld 22. For this purpose, the corrugated metal sheet 16 has at least one through-hole, which in this embodiment is in the form of a groove, but can have any other shape, and in particular a circular shape. This through-hole is made in a straight line with each anchoring element 20. Each of the holes is filled with welding material to form a connection between the primary sealing membrane 8 and the anchoring element 20.

[0074] According to another embodiment, the corrugated metal sheet 16 is anchored to the anchoring element 20 by transmission welding, i.e., welding using a laser source without filler material. In this case, the corrugated metal sheet 16 has no holes.

[0075] In addition, the corrugated metal sheet 16 of the primary sealing membrane 8 is welded along the edge of the corrugated metal sheet.

[0076] exist Figures 2 to 4 In this embodiment, the edge of the corrugated metal sheet 16 is offset from the edge of the primary panel 7. Furthermore, as... Figure 4As shown, the inner sheet of the primary panel 7 advantageously includes a heat protection element 23 along the edge of the corrugated metal sheet 16. The heat protection element 23 is formed, for example, of a composite film or aluminum sheet comprising at least one aluminum foil bonded to at least one glass fiber pad. The heat protection element 23 is advantageously accommodated in a perforated recess formed in the inner sheet 15 of the primary panel 7, and is arranged between the edge and the relaxation groove 21 or in each gap between two relaxation grooves 21. The heat protection element 23 is secured to the inner sheet 15 of the primary panel 7 by bonding and / or snapping. The heat protection element 23 protects the primary panel 7, and in particular protects the insulating polymer foam layer 14 of the primary panel from temperatures that could easily damage the insulating polymer foam layer during the operation of welding the metal sheets together along their edges.

[0077] exist Figure 3 In the embodiment shown, the corrugated portions 17 and 18 are not arranged symmetrically with respect to the two intermediate axes, such as... Figure 3 As shown by the dashed lines in the diagram. Each intermediate axis is parallel to the two opposite edges of the corrugated metal sheet 16, dividing the corrugated metal sheet 16 into two equal parts. More specifically, each corrugated portion 17, 18, adjacent to and parallel to one of the edges used for overlapping the edges of another corrugated metal sheet 16, is positioned at a greater distance d1 or d2 from the adjacent edge than the distance d3, d4 between the corrugated portion 17, 18 and the opposite edge used for overlapping the edges of the adjacent metal sheet. This allows for an increase in the width of the overlapping area between the edges of adjacent corrugated metal sheets 16.

[0078] like Figure 7 As schematically shown, in the overlapping region between two adjacent metal sheets 16 arranged to span two adjacent primary panels 7, the edges of the corrugated metal sheets 16 are welded to the adjacent edges of two anchoring elements belonging to each of the two adjacent primary panels 7, respectively, by another adjacent metal sheet. Therefore, it can be understood that by increasing the width of the overlapping portion, as mentioned above... Figure 3 The proposed plug weld 22 is at least partially covered. This allows for limiting the length of the plug weld 22, which is crucial for the flow tightness of the primary sealing membrane 8, and the flow tightness of the primary sealing membrane 8 must thus be ensured. Alternatively, the plug weld 22 can be replaced by through welds and corner welds on certain anchoring elements 20.

[0079] According to an embodiment not described, in order to limit the number of thermal protection elements 23 to be installed, anchoring elements 20 arranged near the edge of the corrugated metal sheet 16 extend along the edge of the corrugated metal sheet 16 from the edge of the primary panel 7 to a relaxation groove 21 adjacent to and parallel to said edge of the primary panel 7. Therefore, in this region, the anchoring elements 20 serve both to anchor the primary sealing film 8 and to provide thermal protection to the primary panel 7 during the overlapping welding of the edges of the corrugated metal sheets 16.

[0080] According to another embodiment not described, the corrugated metal sheet 16 of the primary sealing membrane 8 is also anchored to the primary thermal insulation barrier 6 at its edges. In this case... Figure 4 The thermal protection element 23 shown is replaced by a metal anchoring element.

[0081] like Figure 5 As shown, the primary panel 7 has cutouts 24 at its corners, allowing the outer sheet 13 of the primary panel 7 to extend beyond the insulating polymer foam layer 14 and the inner sheet 15 of the primary panel 7. Thus, the outer sheet 13 forms a support region 25 at the corner of the primary panel 7, which cooperates directly or indirectly with the retaining plate 26 of the primary anchoring device 27. Furthermore, in the illustrated embodiment, a block 28 is added to the outer sheet 13, having a shape similar to the support region 25, and this block 28 cooperates with the retaining plate 26 to anchor the primary panel 7. Each primary anchoring device 27 cooperates with four support regions 25, each belonging to one of the corners of four adjacent primary panels 7. Each primary anchoring device 27 includes: a stud 29 protruding from one of the secondary panels 3; and a retaining plate 26 fixed to the end of the stud and supporting four support regions 25 abutting against four adjacent primary panels 7, thereby holding them against the secondary thermal insulation barrier 2. The retaining plate 26 has a hole that slides over the stud 29. A nut 30 engages with the threaded end of the stud 29 to secure the retaining plate 26. Furthermore, according to an advantageous embodiment, resilient Belleville washers slide over the stud 29 and between the nut 30 and the retaining plate 26, thereby resiliently anchoring the primary panels 7 to the secondary thermal insulation barrier 2.

[0082] Stud 29 is secured to base 31, which itself is secured to the inner sheet 11 of secondary panel 3. To achieve this, base 31 includes, for example, threads that engage with the complementary threaded end of stud 29. Furthermore, the inner sheet 11 of secondary panel 3 has a cutout that accommodates base 31. This cutout has an inner section of a first diameter and an outer section of a second diameter larger than the first diameter, thus forming a stepped shoulder. Base 31 has a shape complementary to the shape of the cutout. Therefore, the inner surface of base 31 is positioned flush with the inner surface of the inner sheet 11 of secondary panel 3 to form a planar support surface supporting the secondary sealing membrane 5. Furthermore, base 31 has an outer section of a larger diameter than its inner section, such that the outer section of base abuts against the shoulder of the cutout. Base 31 is also attached to secondary panel 3.

[0083] In addition, the stud 29 passes through the orifice formed in the secondary sealing membrane 5 in a sealing manner.

[0084] Figure 8 The embodiment shown differs from the embodiment described above in that the corrugated metal sheet 16 of the primary sealing film 8 is substantially aligned relative to the primary panel 7. In other words, the edges of the corrugated metal sheet 16 extend along some of the edges of the primary panel 7. To achieve this, the corrugated metal sheet 16 preferably has the following width and length dimensions: these dimensions are the total value or an integer multiple of the spacing between the corrugations and are also integer multiples of the size of the primary panel 7, while ignoring the size of the overlapping area between adjacent corrugated metal sheets 16. Therefore, in Figure 8 In the embodiment shown, two edges of each corrugated metal sheet 16 have a length that is substantially three times the side length of the primary panel 7, while the other second edge has a length that is substantially equal to the side length of the primary panel 7.

[0085] Figure 9 It shows in Figure 8 The embodiment describes the overlapping area between two adjacent corrugated metal sheets 16. In this embodiment, the two edge portions of adjacent corrugated metal sheets 16, arranged one over the other, are welded to the anchoring element 20 by plug weld 22 or through-hole weld. The two edge portions are welded to each other by means of a weld, such as a corner weld, arranged between the two anchoring elements 20 respectively fixed to two adjacent primary panels. This embodiment allows the use of corrugated metal sheets with limited dimensions, and the corrugations 17, 18 of the corrugated metal sheets are centered relative to the two central axes of the corrugated metal sheets.

[0086] Figure 10The diagram shows an overlapping area between two adjacent corrugated metal sheets 16 according to a variant of the embodiment. In this variant, the two edge portions arranged to overlap are both welded to one of the anchoring elements 20 by means of plug weld 22 or by through weld, such as... Figure 9 As shown in the variant. However, in this embodiment, the overlapping edge portions cover at least a portion of the plug weld 22 or the penetrating weld of the other edge portion. For this purpose, the corrugated metal sheet 16 has the following structure: in this structure, the corrugations are not arranged symmetrically with respect to the two intermediate axes, as... Figure 3 As described and shown.

[0087] Finally, Figure 11 In this embodiment, the edge portions intended to be overlapped by other edge portions are welded to two anchoring elements 20 belonging to each of the two adjacent primary panels 7 by means of plug weld 22. Then, the other edge portions cover the plug weld 22 in a straight line with the anchoring elements 20 fixed to each of the two adjacent primary panels. This allows for further limitation of the length of the plug weld 22, which is crucial to the flow tightness of the primary sealing film 8, and the flow tightness of the primary sealing film 8 must therefore be ensured.

[0088] Figure 12 Another implementation is shown. This implementation is related to... Figures 2 to 4 The difference between the described and illustrated embodiments lies only in that the corrugated portions 17 and 18 of the corrugated metal sheet 16 are arranged symmetrically with respect to the two intermediate axes, and also in that the edges of the corrugated metal sheet 16 that overlap with the adjacent edges of another corrugated metal sheet do not overlap with any plug weld portions 22. This allows for limitations on the size of the corrugated metal sheet 16.

[0089] Figure 13 and Figure 14 Another embodiment is shown. This embodiment differs from the previous one in terms of the structure of the anchoring element 20 and the type of welding used to attach the corrugated metal sheet 16 to the anchoring element 20. Figure 8 The described implementation methods are different.

[0090] like Figure 14 As shown, the anchoring element 20 includes a base 33 fixed to the primary insulating panel 7 and a sealing ring 33 welded to the primary sealing membrane 8 and fixed to the base 32 in a sealing manner. For this purpose, the base 32 includes a threaded hole 34 with a threaded shank 35 screwed through an orifice formed in the primary sealing membrane 8. The sealing ring 33 is supported against the inner surface of the primary sealing membrane 8 and welded to the primary sealing membrane 8 around the orifice to ensure a seal.

[0091] Figure 15 and Figure 16 Another embodiment of the invention is shown. In this embodiment, the anchoring element 20 includes an insert in the form of a disc 36, which is received in a perforated recess formed on the inner surface of the primary insulating panel 7, and the insert is secured to the primary insulating panel 7. In the illustrated embodiment, the disc-shaped insert 36 is equipped with a threaded shank 37, which is received in a threaded hole formed in a metal portion 38, which is secured to the primary insulating panel 7.

[0092] Reference Figure 6 A cross-sectional view of the methane carrier 70 shows a sealed and insulated tank 71, which has a generally prismatic shape, and is mounted in the twin hulls 72 of a ship. The walls of the tank 71 have: a primary sealing membrane intended to contact the LNG contained in the tank; a secondary sealing membrane 5 disposed between the primary sealing membrane and the twin hulls 72 of the ship; and two thermally insulating barriers disposed between the primary sealing membrane and the secondary sealing membrane and between the secondary sealing membrane and the twin hulls 72, respectively.

[0093] In a manner known per se, the loading / unloading pipeline 73, located on the upper deck of the ship, can be connected to a marine or port terminal by means of appropriate connectors to transfer cargo of liquefied natural gas from or to tank 71.

[0094] Figure 6 An example of a marine terminal with a loading and unloading station 75, an underwater pipeline 76, and a land-based facility 77 is also shown. The loading and unloading station 75 is a fixed marine facility having a mobile arm 74 and a tower-like structure 78 supporting the mobile arm 74. The mobile arm 74 carries bundles of insulated flexible tubing 79 that can be connected to a loading / unloading pipeline 73. The directional mobile arm 74 can accommodate methane carriers of all sizes. Connecting pipes, not described, extend upward within the tower-like structure 78. The loading and unloading station 75 allows methane carriers 70 to be loaded from or unloaded to the land-based facility 77. The land-based facility 77 has a liquefied gas storage tank 80 and a connecting pipe 81 connected to the loading or unloading station 75 by the underwater pipeline 76. The underwater pipeline 76 can transport liquefied gas over a long distance, for example, 5 km, between the loading or unloading station 75 and the land-based facility 77, thereby allowing the methane carrier 70 to remain at a considerable distance offshore during loading or unloading operations.

[0095] To generate the pressure required for the transfer of liquefied gas, pumps mounted on the ship 70 and / or pumps equipped with onshore facilities 77 and / or pumps equipped with loading and unloading stations 75 are used.

[0096] Although the present invention has been described in conjunction with several specific embodiments, it is obvious that the invention is not limited thereto, and the invention includes all technical equivalents and combinations thereof, if they fall within the scope of the invention.

[0097] In the claims section, any reference numerals between parentheses shall not be construed as imposing a limitation on the claims.

Claims

1. A wall (1) of a sealed and thermally insulated tank for storing a liquefied gas, the wall (1) comprising at least one thermally insulating barrier (6) and a sealing membrane (8) anchored to the thermally insulating barrier (6) and intended to be in contact with the liquefied gas, the thermally insulating barrier (6) comprising a first insulating panel, a second insulating panel arranged along a first edge of the first insulating panel, a third insulating panel arranged along a second edge of the first insulating panel, a fourth insulating panel arranged along a third edge of the first insulating panel, a fifth insulating panel arranged along a fourth edge of the first insulating panel, and a sixth insulating panel arranged along an edge of the second insulating panel and along an edge of the third insulating panel, the first edge and the second edge of the first insulating panel being continuous, the first insulating panel, the second insulating panel, the third insulating panel, the fourth insulating panel, the fifth insulating panel and the sixth insulating panel being respectively equipped with a first anchoring element, a second anchoring element, a third anchoring element, a fourth anchoring element, a fifth anchoring element and a sixth anchoring element, wherein, The sealing membrane (8) is welded to the first, second, third, fourth and fifth anchoring elements; the sealing membrane (8) comprises corrugations separated from each other by planar portions (19), the first and second insulating panels having a rigidity less than the rigidity of the planar portions of the sealing membrane, and wherein at least one of the planar portions (19) is arranged astride the first and second insulating panels and is welded, on one hand, to one of the first anchoring elements and, on the other hand, to one of the second anchoring elements, at least one of the planar portions (19) is arranged astride the first and third insulating panels and is welded, on one hand, to one of the first anchoring elements and, on the other hand, to one of the third anchoring elements, at least one of the planar portions (19) is arranged astride the first and fourth insulating panels and is welded, on one hand, to one of the first anchoring elements and, on the other hand, to one of the fourth anchoring elements, at least one of the planar portions (19) is arranged astride the first and fifth insulating panels and is welded, on one hand, to one of the first anchoring elements and, on the other hand, to one of the fifth anchoring elements, wherein at least one of the planar portions (19) is arranged astride the first, second, third and sixth insulating panels and is fixed to one of the first anchoring elements, one of the second anchoring elements, one of the third anchoring elements and one of the sixth anchoring elements.

2. The wall (1) according to claim 1, wherein The sealing membrane (8) comprises a first corrugation (17) extending parallel to a first direction and a second corrugation (18) extending parallel to a second direction, the first direction being perpendicular to the second direction.

3. The wall (1) according to claim 2, wherein The first and second insulating panels have a parallelepiped shape and each have two opposite edges parallel to the first direction and two opposite edges parallel to the second direction.

4. The wall (1) according to any one of claims 1 to 3, wherein The first and second insulating panels are each equipped with a plurality of first and second anchoring elements, and wherein a plurality of the planar portions (19) are arranged astride the first and second insulating panels and are welded, respectively, to one of the first anchoring elements and to one of the second anchoring elements.

5. A wall (1) according to any one of claims 1 to 3, wherein The sealing membrane (8) is welded to at least one of the first anchoring elements and at least one of the second anchoring elements by means of plug welding or penetration welding.

6. A wall (1) according to any one of claims 1 to 3, wherein The at least one first anchoring element and the at least one second anchoring element each comprise a metal plate which is fixed in a hole- bearing recess formed in one of the first and second insulating panels.

7. A wall (1) as claimed in claim 6, wherein The metal plate has a square, rectangular or disc shape.

8. The wall of any one of claims 1 to 3, wherein, The first and second insulating panels have a slack groove facing the corrugations of the sealing membrane (8).

9. A wall (1) according to claim 8, wherein The at least one first anchoring element and the at least one second anchoring element are each placed on an edge portion of the first and second insulating panels, the edge portions of the first and second insulating panels being bounded by at least one of the slack groove of the first insulating panel and the slack groove of the second insulating panel.

10. A wall (1) according to any one of claims 1 to 3, wherein The sealing membrane (8) comprises a plurality of corrugated metal sheets (16), each corrugated metal sheet (16) having edges which are each lap-welded to the edges of an adjacent corrugated metal sheet (16).

11. A wall (1) according to claim 10, wherein The planar portion arranged to straddle the first and second insulating panels and welded to the first and second anchoring elements is made in one piece from a single corrugated metal sheet (16).

12. The wall of claim 11, wherein, The planar portion arranged to straddle the first and second insulating panels and welded to the first and second anchoring elements belongs to a first edge portion of one of the corrugated metal sheets (16); the first edge portion is overlaid by a second edge portion of an adjacent corrugated metal sheet (16), the first edge portion is welded to the first anchoring element by means of a first plug weld, and the first edge portion is welded to the second anchoring element by means of a second plug weld, the second edge portion overlies at least part of the first plug weld and the second plug weld, and the second edge portion is sealingly fillet-welded to the first edge portion.

13. A wall (1) according to claim 10, wherein The planar portion arranged to straddle the first and second insulating panels and welded to the first and second anchoring elements is made from first and second edge portions of two adjacent corrugated metal sheets (16) which are lap-welded to one another.

14. The wall of claim 13, wherein, The first edge portion is intended to be overlaid by the second edge portion, the first edge portion is welded to the first anchoring element by means of a weld, the second edge portion is welded to the second anchoring element, overlies at least part of the weld, and the second edge portion is fillet-welded to the first edge portion in a sealing manner.

15. A wall (1) according to claim 10, wherein The first and second insulating panels each have a heat protection element (23) facing the edges of the corrugated metal sheets (16).

16. A wall (1) according to claim 15, wherein The thermal protection element (23) is formed in the form of a composite film or aluminum sheet comprising at least one aluminum foil associated with at least one glass fiber mat.

17. A sealed and thermally insulated tank, comprising a wall (1) according to any one of claims 1 to 16.

18. A ship (70) for transporting a fluid, comprising a hull (72) and a tank (71) according to claim 17 arranged in the hull.

19. A transfer system for transferring a fluid, the system comprising: The ship (70) according to claim 18; insulated lines (73, 79, 76, 81) arranged to connect the tank (71) mounted in the hull of the ship to a floating or onshore storage facility (77); and a pump for driving fluid through the insulated lines from the floating or onshore storage facility to the tank of the ship or vice versa.

20. A method for loading and unloading a vessel (70) according to claim 18, wherein, Transporting fluid through insulated lines (73, 79, 76, 81) from a floating or onshore storage facility (77) to a tank (71) of the ship or vice versa.

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