Method for assembling wall of sealed and heat-insulated tank

Abstract

The invention relates to a method for assembling a wall of a sealed and thermally insulated tank, comprising: a) assembling (2001) a secondary insulation barrier (2) on a support wall (3); b) arranging (2002) a base (98, 398) of the anchoring system in a recess (197, 395) formed in the secondary insulation barrier (2); c) screwing the temporary positioning element (50) into the positioning hole (40, 340); d) arranging (2004) the strake (21) above the temporary positioning element (50) such that the head (82) of the temporary positioning element (50) locally deforms the strake (21); e) at the local deformation, making (2005) a through hole (190) in the strake (21) from the top of the strake (21); and f) screwing a threaded stud (200) through the through hole (190) into the positioning hole (40, 340) so as to form a primary anchoring system for the one or more elements of the primary insulation barrier.

Description

Technical Field

[0001] The present invention relates to the field of sealed and thermally insulated tanks with membranes. In particular, the present invention relates to an assembly method for assembling the walls of such tanks. Background Art

[0002] The tank of a carrier for transporting liquefied natural gas generally comprises a double wall, which comprises, from the inside to the outside of the tank, a primary sealing membrane, a primary thermal insulation barrier, a secondary sealing membrane and a secondary thermal insulation barrier. The secondary insulation barrier comprises a secondary insulation block, which comprises a cover plate, which forms a support surface for the secondary sealing membrane. The primary insulation barrier comprises a primary insulation block. The primary insulation block is anchored to the secondary insulation barrier.

[0003] Document FR 2887 010A1 describes a wall of a sealed and thermally insulated tank in which an anchoring system makes it possible to anchor a primary insulating block to a secondary insulating block. The anchoring system comprises a plate with a bore for receiving the lower threaded portion of a stud for anchoring the primary insulating block. When assembling the tank wall, the operator must pass the stud through the secondary membrane so that the lower threaded portion of the stud can be received in the bore. However, at this point in the tank assembly, the bore is not visible to the operator because the secondary membrane has been positioned on top of the bore. Therefore, it may be difficult for the operator to position the stud.

[0004] Document FR 3090 810 A1 describes another wall of a sealed and insulated tank, in which an anchoring system makes it possible to anchor a primary insulating block to a secondary insulating block. The anchoring system comprises a base attached to a covering plate. A movable part is held in the base in the direction of the thickness of the wall and is mounted in the base in a movable manner. The movable part has an internal threaded hole opening on the upper surface of the movable part. The upper surface of the movable part is flush with the upper surface of the covering plate, and the movable part is mounted in the base so that the movable part can move freely in a translational manner at least parallel to the longitudinal direction of the welding flange. The internal threaded hole in the movable part is intended to receive the lower threaded portion of the stud for anchoring the primary block.

[0005] The fact that the movable part is freely mounted in a translational manner makes it possible to reduce mechanical stresses on the sealing membrane, such as the following mechanical stresses: mechanical stresses that cause the thermal insulation barrier to shrink when the tank is cooled, and / or mechanical stresses when the thermal insulation barrier is deformed during use. However, the fact that the movable part is freely mounted in a translational manner may also lead to some difficulties when assembling the tank wall. Specifically, when assembling the tank wall, the operator must pass the stud through the secondary membrane so that the lower threaded portion of the stud can be received in the internal threaded hole of the movable part. However, at this point in the tank assembly, since the secondary membrane has been positioned on top of the movable part, the movable part is not visible to the operator. Therefore, the operator cannot ensure the correct positioning of the movable part by vision. Summary of the invention

[0006] The object of the invention is to allow easier assembly of the tank wall for the operator in the above mentioned point.The idea underlying the invention is to use temporary positioning elements during assembly of the tank wall in order to position the stud satisfactorily relative to the base of the primary anchoring system into which it must be screwed.

[0007] According to an embodiment, the present invention provides an assembly method for assembling the wall of a sealed and thermally insulated tank for storing a fluid, the tank wall comprising, in sequence in the thickness direction, a secondary insulating barrier held on a supporting wall, a secondary sealing membrane arranged to abut against the secondary insulating barrier, and a primary insulating barrier arranged to abut against the secondary sealing membrane,

[0008] The secondary sealing membrane comprises a pair of welded metal strakes, and

[0009] The primary insulation barrier comprises juxtaposed primary insulation elements;

[0010] The assembly method comprises the following steps:

[0011] a) assembling a secondary insulating barrier on a supporting wall, the secondary insulating barrier forming a supporting surface for a secondary sealing membrane, and the secondary insulating barrier having a recess opening on the supporting surface;

[0012] b) arranging an anchor system base in the recess, the anchor system base comprising a positioning hole having a first internal thread;

[0013] c) providing a temporary positioning element, the temporary positioning element comprising a rod-shaped member and a head at one end of the rod-shaped member, the rod-shaped member having a threaded portion, and the head having a cavity on the side opposite to the rod, and screwing the temporary positioning element into the positioning hole by means of the threaded portion;

[0014] d) placing the strake on top of the temporary positioning element so that the head produces a local deformation of the strake;

[0015] e) making through holes in the strakes from above at the local deformations;

[0016] f) removing the temporary positioning element from the positioning hole, and screwing the threaded stud through the through hole from above the strake into the positioning hole, the anchor system base and the threaded stud forming a primary anchor system;

[0017] g) Arranging one or more primary insulating elements on said strakes and attaching said one or more primary insulating elements to a secondary insulating barrier by means of a primary anchoring system.

[0018] The temporary positioning element thus makes it possible to create through holes in the strakes precisely at the locations where the studs must pass through the strakes to be screwed into the base of the anchoring system. These operations are therefore easy for the operator to perform even if the strakes conceal the base of the anchoring system.

[0019] It is noted that the temporary positioning elements are not intended to be present in the assembled tank wall, since they are replaced by threaded studs during implementation of the assembly method.

[0020] Depending on the implementation, such a method may include one or more of the following features.

[0021] According to an embodiment, the strake comprises, at two opposite ends of the strake, two raised edge portions raised towards the interior of the tank.

[0022] According to an embodiment, the assembly method comprises welding the raised edge portion to a welding flange, the welding flange being mechanically held to the secondary insulation barrier.

[0023] According to an embodiment, in step d), the raised edge portions are each in contact with a welding flange.

[0024] According to an embodiment, the head has at least one protruding edge portion for locally deforming the strake.

[0025] According to an embodiment, the head has two protruding edge portions for locally deforming the strake, the two protruding edge portions being arranged on both sides of the rod-shaped member and aligned in the alignment direction.

[0026] According to an embodiment, the temporary positioning element is screwed into the positioning hole such that at least one of the protruding edge portions is parallel to the raised edge portion.

[0027] According to an embodiment, step e) comprises punching the strake by driving the punch just into the cavity.

[0028] According to an embodiment, the shaft has an aperture opening into the cavity in the head.

[0029] According to an embodiment, the orifice has a diameter strictly smaller than the larger inner diameter of the cavity, so that an inner shoulder is formed at the bottom of the cavity, at the junction between the orifice and the cavity. According to an embodiment, in this case, step e) comprises:

[0030] - Punching the strakes by driving the punch into the cavity and the orifice until the stop of the punch abuts against the internal shoulder, the punch including a fillet or shoulder at the stop.

[0031] The abutment of the punch with the inner shoulder of the temporary positioning element prevents the secondary insulation barrier from being damaged due to the punch being driven too deep. In addition, the operator can be sure that the punch has been properly punched to the strake.

[0032] According to an embodiment, the punch is slidably mounted in a die, the first end of the die comprises a second cavity capable of receiving a head of the temporary positioning element, and step e) further comprises:

[0033] - When the punch is in the stopped position, the die is slid relative to the punch in the direction of the strake, so that the first end of the die makes the through hole by shearing the strake.

[0034] Thus, the through hole can be easily produced in two consecutive steps using a punching and cutting tool comprising a punch and a die. The punching and cutting tool is simple and reusable. The first end of the die can be beveled around the second cavity to better shear the strakes, thereby facilitating the production of the through hole.

[0035] Driving the stamping part into the cavity and the orifice and subsequently sliding the die relative to the stamping part to a stop position of the die can be performed by applying a first impact and a second impact, respectively, to a second end of the die opposite to the first end, for example, by a hand tool such as a hammer or by a pneumatic tool inserted into the second end.

[0036] According to an embodiment, the second cavity comprises a second shoulder and the die is slid relative to the punch towards the strake until the head of the temporary positioning element abuts against the second shoulder.

[0037] The abutment of the heads of the temporary positioning elements prevents the secondary insulating barriers or strakes from being damaged by the mould being driven too deep.

[0038] According to an embodiment, the aperture comprises a second internal thread.

[0039] Depending on the implementation:

[0040] - step e) comprises inserting a cutting tool into the cavity and screwing the cutting tool into the orifice of the shaft, and then actuating the cutting tool; and

[0041] - Step f) comprises using a tool to unscrew the temporary positioning element from the positioning hole.

[0042] According to an embodiment, the first internal thread and the second internal thread have opposite thread directions.

[0043] According to an embodiment, step f) comprises imparting a rotation to the tool in the aperture of the shaft.

[0044] According to an embodiment, the first internal thread is a right-hand thread and the second internal thread is a left-hand thread.

[0045] According to an embodiment,

[0046] the assembly method comprises, after step e) and before step f), a step e2) which comprises making marks on the strakes from above, the marks being positioned at a predetermined distance from the through-holes made in step e); and

[0047] - In step f), screw the threaded stud into the pilot hole using the mark as a visual reference.

[0048] Preferably, the mark does not affect the mechanical strength of the strake. Therefore, according to an embodiment, the mark is made without cutting or slotting the strake. For example, the mark is made using a felt-tip pen, indelible or otherwise.

[0049] According to an embodiment, the marking is a point-type marking, such as a dot or a cross.

[0050] According to an embodiment, the marking is a circle or an arc of a circle.

[0051] According to an embodiment, the marking comprises a straight line segment.

[0052] According to an embodiment, in step f), the threaded stud is partially screwed into the positioning hole, and then the position of the threaded stud is adjusted relative to the mark, and then the threaded stud is completely screwed into the positioning hole.

[0053] According to an embodiment, the threaded stud comprises a collar.

[0054] According to an embodiment, in step f), the threaded stud is screwed into the positioning hole without the collar obscuring the mark. To this end, the predetermined distance makes it possible to screw the threaded stud into the positioning hole in step f) without the collar obscuring the mark. For this purpose, the distance between the center of the through hole and the mark is greater than or equal to the radius of the outer contour of the collar.

[0055] According to an embodiment, when the threaded stud is screwed into the positioning hole, the collar is arranged to abut against the column plate. For example, when the threaded stud is screwed in, the distance between the mark and the outer contour of the collar is between 0.1 mm (including 0.1 mm) and 4 mm (including 4 mm).

[0056] According to an embodiment, the assembly method comprises welding the collar to the strake in a sealed manner.

[0057] According to an embodiment, the recess is formed in a secondary insulating element of the secondary insulating barrier.

[0058] According to an embodiment, the recess is formed at a distance from an edge of the secondary insulating element.

[0059] According to an embodiment, the secondary insulating element comprises a blind hole formed in the bottom of the recess and opening into the recess.

[0060] According to an embodiment, the shaft comprises a non-threaded distal portion on a side opposite to the head.

[0061] According to an embodiment, in step c), the temporary positioning element is screwed into the positioning hole by means of the threaded portion until the non-threaded distal end portion is received in the blind hole.

[0062] According to an embodiment, the free end of the non-threaded distal portion is chamfered.

[0063] This chamfer tends to facilitate the centering of the temporary positioning element and, where applicable, the movable portion of the anchoring system base.

[0064] The term "secondary insulating element" refers to a thermal insulating element that contributes to forming a secondary insulating barrier. The secondary insulating element may in particular be a secondary insulating box, a secondary insulating block, a packing seal arranged between secondary insulating boxes or blocks or a bridging element connecting secondary insulating blocks.

[0065] According to an embodiment, the secondary insulation element is a secondary insulation box.

[0066] According to an embodiment, the secondary insulation box includes a bottom plate, a cover plate and a side plate, wherein the side plate connects the cover plate to the bottom plate and keeps the cover plate a distance away from the bottom plate so as to define an internal space of the secondary insulation box, and the internal space of the secondary insulation box is filled with a thermal insulation package, such as perlite or polyurethane foam optionally reinforced with glass fiber.

[0067] According to an embodiment, the secondary insulating elements are secondary insulating blocks.

[0068] According to an embodiment, the secondary insulating block comprises an insulating foam block and a cover plate placed on the insulating foam block, the upper surface of the cover plate forming a support surface for the secondary sealing membrane.

[0069] According to an embodiment, the covering panels are made of plywood.

[0070] According to an embodiment, the insulating foam is a polyurethane foam, optionally reinforced with glass fibers, the polyurethane foam having a relative humidity of 130 kg / m 3 Up to 200kg / m 3 The density between.

[0071] According to an embodiment, the recess extends into at least a part of the thickness of the covering plate.

[0072] According to an embodiment, the recess is open to the outside on the insulating foam block.

[0073] According to an embodiment, the recess also extends into a part of the thickness of the insulating foam block.

[0074] According to an embodiment, the secondary insulating block further comprises a bottom plate, the insulating foam block being arranged between the bottom plate and the cover plate.

[0075] According to an embodiment, the bottom panel is made of plywood.

[0076] According to an embodiment, the recess is formed between at least two secondary insulating elements, for example between four secondary insulating elements.

[0077] According to an embodiment, a secondary anchoring member for anchoring one or more secondary insulation elements is received in the recess.

[0078] According to an embodiment, the secondary anchoring member is mechanically connected to the supporting wall.

[0079] According to an embodiment, the anchoring system base comprises:

[0080] - a movable part, the movable part comprising a body having an upper surface flush with the upper surface of the cover plate, the positioning hole passing through the body; and

[0081] - a retaining portion which is attached to the cover plate and interacts with the movable portion so that the movable portion stops in the recess in the thickness direction;

[0082] The recessed portion and the holding portion are configured to allow the movable portion to move perpendicularly to the thickness direction.

[0083] According to an embodiment, the recessed portion and the retaining portion are configured to allow the movable portion to move in a movement direction parallel to the longitudinal direction of the strake.

[0084] According to one embodiment, the mark is a point-type mark, such as a dot or a cross, and an imaginary straight line passing through the center of the through hole and parallel to the movement direction passes through the mark. According to another embodiment, the mark is a circle or an arc of a circle, and an imaginary straight line passing through the center of the through hole and parallel to the movement direction intersects the mark. According to another embodiment, the mark includes a straight line segment perpendicular to the movement direction. According to another embodiment, the mark includes two straight line segments perpendicular to the movement direction and diametrically opposite relative to the center of the through hole. The mark can then serve as a visual reference for positioning the stud and the movable part in the correct position, thereby allowing the movable part to move in both directions of the movement direction.

[0085] According to an embodiment, the cover plate has two parallel grooves for holding the welding flange on the cover plate, and the movement direction is parallel to the grooves.

[0086] The primary insulating barrier is intended to support the primary sealing membrane. According to an embodiment, the primary sealing membrane rests on the primary insulating barrier.

[0087] According to an embodiment, the fluid is a liquefied gas.

[0088] According to an embodiment, the liquefied gas is LNG, in other words a mixture with a high methane content stored at a temperature of about -162° C. at atmospheric pressure. Other liquefied gases are also conceivable, in particular ethane, propane, butane or ethylene. The liquefied gas can also be stored at a relative pressure of, for example, between 2 bar and 20 bar, in particular at a relative pressure of about 2 bar. Various technologies can be used to produce the tank, in particular in the form of an integrated membrane tank or a self-supporting tank.

[0089] Such tanks may form part of an onshore storage facility, e.g. for storing LNG, or may be installed on a floating structure either coastal or in deep water, in particular on a liquefied gas carrier, a floating storage and regasification unit (FSRU), a remote floating production and storage unit (FPSO), etc. Such tanks may also be used as fuel tanks on board any type of transport vessel.

[0090] According to an embodiment, a transport ship for transporting a fluid includes a catamaran and a tank as described above arranged in the catamaran.

[0091] According to an embodiment, the present invention also provides a system for transporting fluids, the system comprising: a transport ship as described above; an isolated pipeline arranged to connect a tank installed in the hull of the transport ship to a floating or onshore storage facility; and a pump for pumping a flow of fluid / liquefied gas from the floating or onshore storage facility to the tank of the transport ship, or from the tank of the transport ship to the floating or onshore storage facility, through the isolated pipeline.

[0092] According to an embodiment, the present invention also provides a method for loading or unloading a transport vessel, wherein fluid / liquefied gas is transported from a floating or onshore storage facility to a tank of a transport vessel, or from a tank of a transport vessel to a floating or onshore storage facility via an isolated pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0093] The invention will be better understood and other objects, details, features and advantages of the invention will become more apparent from the following description of a number of particular embodiments of the invention, provided purely by way of non-limiting example, with reference to the accompanying drawings.

[0094] [ Figure 1 ] Figure 1 It is a three-dimensional image of a partially cut-away tank wall.

[0095] [ Figure 2 ] Figure 2 is a top view of a secondary insulation block that can be used to produce Figure 1 Secondary isolation barrier in the tank wall.

[0096] [ Figure 3 ] Figure 3 yes Figure 2 The secondary isolation block shown in FIG. Figure 2 Cross-sectional view of a section taken from GG.

[0097] [ Figure 4 ] Figure 4 yes Figure 3 The enlarged view of detail H in Figure 2 A cross section of GG shows Figure 1 The primary anchoring system is identified by IV.

[0098] [ Figure 5 ] Figure 5 is shown for Figure 1 A block diagram of the steps in a method of assembling a tank wall.

[0099] [ Fig. 6A ] Fig. 6A is a top perspective view of a temporary positioning element that may be used in the assembly method.

[0100] [ Figure 6B ] Figure 6B yes Fig. 6A Side view of the temporary positioning element in FIG.

[0101] [ Figure 6C ] Figure 6C for Figure 6B A view of a section taken along AA in FIG.

[0102] [ Fig. 7A ] Fig. 7A is similar to Figure 3 A cross-sectional view showing the use of Fig. 6A , Figure 6B and Figure 6C The principles of the steps of the assembly method of the temporary positioning element are shown in FIG.

[0103] [ Figure 7B ] Figure 7B From above along Fig. 7A The arrow B in the Fig. 7A Schematic diagram of the portion of the strake visible in Figure 1, showing the markings made on the strake.

[0104] [ Figure 7C ] Figure 7C is similar to Figure 7B , showing the markings made on the strakes according to the variant.

[0105] [ Fig.7D ] Fig.7D is similar to Figure 7B , showing markings made on the strakes according to another variant.

[0106] [ Figure 8 ] Figure 8 is similar to Fig. 7A sectional view showing a further embodiment and Fig. 7A Same steps.

[0107] [ Fig. 9 ] Fig. 9 is similar to Fig. 7A and Figure 8 A cross-sectional view showing a further embodiment of the invention Fig. 7A and Figure 8 Same steps.

[0108] [ Fig.10 ] Fig.10 The tank of a liquefied gas carrier and the dock for loading / unloading the tank are schematically depicted in a partially cutaway manner.

[0109] [ Fig.11 ] Fig.11 is a perspective view of a tool that can be used to make through holes in a strake during a step of an assembly method, wherein Fig. 7A The principle of this assembly method is shown.

[0110] [ Fig.12 ] Fig.12 yes Fig.11 A side view of a portion of the tool shown in FIG.

[0111] [ Fig.13 ] Fig.13 yes Fig.11 A cross-sectional view of another portion of the tool shown in FIG.

[0112] [ Fig.14 ] Fig.14 is similar to Fig. 7A A cross-sectional view showing Fig.11 use of tools. DETAILED DESCRIPTION

[0113] Figure 1 The multilayer structure of a sealed and thermally insulated tank 1 for storing liquefied fluids such as liquefied natural gas (LNG) is shown. The tank 1 has a generally polyhedral shape and comprises several walls. The walls of the tank 1 comprise, in order from the outside to the inside of the tank 1 in the thickness direction: a secondary thermal insulation barrier 2 held on a support structure 3, a secondary sealing film 4 arranged to abut against the secondary thermal insulation barrier 2, a primary thermal insulation barrier 5 arranged to abut against the secondary sealing film 4, and a primary sealing film 6 intended to be in contact with the liquefied natural gas contained in the tank 1.

[0114] The support structure 3 of the tank 1 may in particular be formed by the hull or catamaran of a transport vessel. The support structure comprises a plurality of support walls 3 defining the general shape of the tank 1, which is generally a polyhedral shape.

[0115] The secondary thermal insulation barrier 2 comprises a plurality of secondary insulation blocks 7 held on a support wall 3. The secondary insulation blocks 7 have a substantially parallelepiped shape and are arranged in parallel rows. Three rows are indicated by letters A, B and C.

[0116] The secondary insulating blocks 7 are held on the supporting wall 3, for example, by secondary anchoring members 88. Adhesive beads (not shown) are placed between the secondary insulating blocks 7 and the supporting wall 3 to compensate for any deviations between the supporting wall 3 and a flat reference surface. If necessary, kraft paper can be inserted between the adhesive beads and the supporting wall 3 to prevent the adhesive beads from adhering to the supporting wall 3. The secondary anchoring members 88 can vary in number, for example, for each secondary insulating block 7, 2 secondary anchoring members 88 to 6 secondary anchoring members 88 are provided, and the secondary anchoring members 88 are placed, for example, at the corners of four secondary insulating blocks 7 and / or in the gap between two secondary insulating blocks 7. The secondary anchoring members 88 can be produced in various ways according to requirements.

[0117] Alternatively, the above-mentioned kraft paper is omitted and the secondary insulating block 7 is held on the supporting wall 3 due to the attachment of adhesive beads.

[0118] Figure 2 and Figure 3One of the secondary insulating blocks 7 is shown in more detail. The secondary insulating block 7 comprises an insulating foam block 11 and a cover plate 10 arranged on the insulating foam block 11. The foam of the insulating foam block 11 may be an expanded polyurethane foam, optionally an expanded polyurethane foam reinforced with glass fibers. The cover plate 10 may be made of plywood. A bottom plate 12 may be placed under the insulating foam block 11 so that the insulating foam block 11 is sandwiched between the cover plate 10 and the bottom plate 12. The bottom plate 12 may be made of plywood.

[0119] refer to Figure 2 , the cover plate 10 has two grooves 20, each of which extends through the thickness of the cover plate 10. The two grooves 20 are parallel to each other and therefore extend in the direction indicated by the arrow 1000 in the figure.

[0120] Back to Figure 1 It can be seen that the secondary sealing membrane 4 comprises a continuous layer of strakes 21 made of metal, the strakes 21 having a raised edge portion 32 that is raised toward the inside of the tank. The strakes 21 are welded in pairs on both faces of the welding flange 35 via the raised edge portion 32 of the strakes 21 (see Fig. 7A ). The welding flange 35 has an L-shaped cross section. The raised edge portion 32 of the strake 21 is welded to one arm of the L-shaped piece, while the other arm of the L-shaped piece is engaged in the groove 20 (see Fig. 7A ). The distance between two grooves 20 corresponds to the width of the strake 21, and the distance between the free edge of the secondary insulating block 7 and the adjacent groove 20 corresponds to the width of the strake 21, so that the strake 21 forms a joint between two adjacent insulating blocks 7. Therefore, the secondary sealing membrane 4 is retained on the secondary thermal insulation barrier 2. The welding flange 35 and the groove 20 form a sliding joint, thereby allowing the strake 21 to shrink and deform relative to the secondary insulating block 7.

[0121] The strake 21 is composed of, for example, In other words, the strake 21 is made of a material having a coefficient of expansion of usually 1.2×10 -6 K -1 Up to 2×10 -6 K -1 An alloy between iron and nickel. The expansion coefficient is usually about 7×10 -6 K -1 Up to 9×10 -6 K -1 An alloy of iron and manganese.

[0122] refer to Figure 1The primary thermal insulation barrier 5 comprises a plurality of primary insulation blocks 22, which are stacked and straddled on two rows of secondary insulation blocks 7. The primary insulation blocks 22 are anchored to the secondary insulation blocks 7 using a primary anchoring system 97. The primary anchoring system 97 is separated from the secondary anchoring member 88 and offset relative to the secondary anchoring member 88. The primary insulation blocks 22 have a substantially parallelepiped shape and are arranged in parallel rows. In addition, the primary insulation blocks 22 have the same dimensions as the secondary insulation blocks 7, except that the thickness of the primary insulation blocks 22 in the thickness direction of the wall of the tank 1 may be different, in particular, the thickness of the primary insulation blocks 22 in the thickness direction of the wall of the tank 1 is smaller.

[0123] like Figure 1 As shown, the primary sealing membrane 6 comprises a continuous layer of a rectangular metal sheet 33 having two sets of mutually perpendicular corrugations. The first set of corrugations 55 extends perpendicularly to the rows of insulating blocks A, B, C, and therefore perpendicularly to the raised edge portions 32 of the strakes 21, and has a regular spacing 57. The second set of corrugations 56 extends parallel to the rows of insulating blocks A, B, C, and therefore parallel to the raised edge portions 32 of the strakes 21, and has a regular spacing 58. Preferably, the first set of corrugations 55 is higher than the second set of corrugations 56.

[0124] According to other embodiments, the primary sealing membrane 6 has a structure similar to the secondary sealing membrane 4, in other words, the primary sealing membrane 6 is made of an assembly of strakes having a raised edge portion.

[0125] Now refer to Figure 2 , Figure 3 and Figure 4 The primary anchoring system 97 is described below. The primary anchoring system 97 includes an anchoring system base 98 (hereinafter referred to as “base 98 ” for convenience) and a stud 200 .

[0126] The base 98 includes a movable portion 110 and a retaining portion 120. The retaining portion 120 is disposed in the counterbore 198 and is attached to the cover plate 10, for example, by attachment screws 121 (in Figure 4 121 is not visible, but the location of the attachment screw 121 is Figure 2 ) and / or is attached to the cover plate 10 by adhesive bonding. The movable portion 110 is arranged in the housing 199. The movable portion 110 includes a body 111, and the upper surface 111A of the body 111 is flush with the surface of the cover plate 10. The retaining portion 120 interacts with the movable portion 110 so as to stop the movable portion 110 in the thickness direction of the wall of the tank 1 while allowing the movable portion 110 to move in a manner perpendicular to the thickness direction of the wall of the tank 1. More specifically, the movable portion 110 can be moved at least in the moving direction 1001 (see Figure 2 and Figure 4 ) and the moving direction 1001 is parallel to the direction 1000 along which the groove 20 extends.

[0127] As long as the above-described movement of the movable portion 110 is allowed, the holding portion 120 and the movable portion 110 may each have various geometric shapes.

[0128] The body 111 has a positioning hole 40 that passes through the body 111 and will be described in further detail below.

[0129] The housing 199 opens into the counterbore 198. The assembly including the counterbore 198 and the housing 199 will be referred to hereinafter as the "recess 197".

[0130] An assembly method 2000 for assembling the wall of the tank 1 is now described.

[0131] In the first step 2001 of the assembly method 2000 (see Figure 5 ), the secondary insulation barrier 2 is assembled on the support wall 3, in which case, by referring to the above Figure 1 The described juxtaposition of the secondary insulating blocks 7 in parallel rows allows the assembly of the secondary insulating barrier 2 on the supporting wall 3. The secondary insulating barrier 2 thus comprises recesses 197 provided in the following ratio: for each secondary insulating block 7 one recess 197 is provided.

[0132] In step 2002, the base 98 is placed in the recess 197. This can be done after assembling the secondary insulating barrier 2. Alternatively, the base 98 can already be placed in the recess 197 of each secondary insulating block 7 before assembling the secondary insulating barrier 2 on the supporting wall 3. In particular, the secondary insulating blocks 7 can be prefabricated: in the secondary insulating block 7, the base 98 is already placed in the recess 197.

[0133] Next, in step 2003, a temporary positioning element 50 is provided.

[0134] exist Fig. 6A , Figure 6B and Figure 6C 4 shows a temporary positioning element 50. The temporary positioning element 50 comprises a rod-shaped member 60 and a head 82 located at one end of the rod-shaped member 60. The rod-shaped member 60 has a threaded portion 62 and a non-threaded distal portion 63. The non-threaded distal portion 63 is located at the end of the rod-shaped member 60 opposite to the head 82; therefore, the threaded portion 62 is located between the end of the rod-shaped member 60 supporting the head 82 and the non-threaded distal portion 63. The threaded portion 62 is intended to interact with a corresponding internal thread included in the positioning hole 40.

[0135] Still during step 2003, the temporary positioning element 50 is screwed into the positioning hole 40 through the threaded portion 62. Then, the non-threaded distal portion 63 is received in the blind hole 196 (see Figure 4 ), a blind hole 196 is formed in the bottom of the recess 197 and opens into the recess 197. Preferably, the free end 64 of the non-threaded distal portion 63 is chamfered (see Figure 6B and Figure 6C ). This chamfer tends to facilitate the centering of the temporary positioning element 50 and the movable part 110.

[0136] like Figure 4 As shown, a recess 197 is made in the thickness of the cover plate 10, so that the housing 199 is open on the insulating foam block 11, and a blind hole 196 is made in the insulating foam block 11. Alternatively, the housing 199 may not be open on the insulating foam block 11. In this case, the blind hole 196 may be made only on the cover plate 10. Alternatively, the recess 197 may be made on the thickness portion of the cover plate 10 and on a partial thickness portion of the insulating foam block 11.

[0137] At the end of step 2003 , the movable part 110 is held in place by the temporary positioning element 50 , with the head 82 of the temporary positioning element 50 protruding relative to the movable part 110 and located above the surface 111A.

[0138] In step 2004, the strake 21 is placed on top of the temporary positioning element 50. To this end, Fig. 7A As schematically shown in FIG. 1 , a welding flange 35 may be inserted into each of the two grooves 20 located on both sides of the recess 197 , and the strakes 21 may be positioned such that the raised edge portions 32 of the corresponding strakes 21 abut against the welding flanges 35 .

[0139] like Fig. 7A As can be seen in the figure, since the head 82 of the temporary positioning element 50 protrudes and the strake 21 has a small thickness, the head 82 causes local deformation of the strake 21. In other words, the presence of the head 82 causes the strake 21 to be locally deformed relative to the normal flat shape of the strake 21.

[0140] The head 82 has two protruding edge portions 89 (see Fig. 6A), the two protruding edge portions 89 are located on both sides of the rod-shaped member 60 and are aligned in the alignment direction 999. In this case, before the strake 21 is placed in place, the alignment direction 999 can be parallel or approximately parallel to the direction 1000 of the groove 20 (for example, within a range of ±10°). This result can be achieved by speculation when screwing into the temporary positioning element 50 in step 2003. It will be understood that in this way, the protruding edge portion 89 indicates that the direction of the larger slope of the local deformation of the strake 21 is perpendicular or approximately perpendicular to the direction 1000 of the groove 20.

[0141] In step 2005, through holes 190 (not in the Fig. 7A shown in Figure 7B In order to manufacture the through hole 190, the head 82 of the temporary positioning element 50 has a cavity 83 (see Fig. 6A , Figure 6B , Figure 6C ). It will be appreciated that the presence of cavity 83 enables through-hole 190 to be made in strake 21 in a variety of ways, as cavity 83 allows a piercing tool to pass through strake 21 which would not be possible if head 82 were solid.

[0142] The through hole 190 can be manufactured in various ways in step 2005. In a particular example, the through hole 190 is manufactured as follows:

[0143] - First, the strake 21 is punched by driving a punch perpendicular to the strake 21 into the cavity 83; Fig. 7A , arrow 899 indicates the movement of the stamping part; the stamping part may be the stamping part 500 described below or a different stamping part;

[0144] - Secondly, a cutting tool (not shown) is then inserted into the cavity 83 through the hole made by the stamping, the cutting tool being screwed into the orifice 84 presented by the temporary positioning element 50 (see Fig. 6A and Figure 6C and then actuating the cutting tool, which actuates the through hole 190 to the desired size. The cutting tool manufactures the through hole 190 by partially shearing the strake 21 using the orifice 84 as a holding device.

[0145] Advantageously, the orifice 84 is internally threaded and the insertion of the cutting tool is performed by screwing using the internal thread of the orifice 84. Fig. 7A In the figure, arrow 949 indicates the direction in which the cutting tool is turned.

[0146] The orifice 84 opens into the cavity 83 and extends through the rod 60. Preferably, the orifice 84 is not a blind hole, in other words, the orifice 84 also opens into the free end of the non-threaded distal portion 63. This makes it possible to simplify the manufacture of the temporary positioning element 50. As shown in the figure, the orifice 84 has a diameter strictly smaller than the larger inner diameter of the cavity 83, so that a shoulder 83A is formed at the bottom of the cavity 83, at the junction of the orifice 84 and the cavity 83 (see Fig.14 ).

[0147] refer to Figures 11 to 14 , describes another way to make through hole 190 in step 2005. Fig.11 FIG. 4 is a perspective view of a punching and cutting tool 400 (hereinafter referred to as "tool 400"). Tool 400 includes: Fig.12 The stamping 500 shown and Fig.13 Mold 600 is shown.

[0148] refer to Fig.12 , the stamping 500 generally has the shape of a stepped cylinder. A tip end 509 is provided at the top of the first end portion 510 of the stamping 500. The tip end 509 is, for example, a conical shape as shown. The stamping 500 has a second end portion 530 opposite to the tip end 509, and a middle portion 520 between the first end portion 510 and the second end portion 530. The first end portion 510, the second end portion 530 and the middle portion 520 are cylindrical. The outer diameter of the first end portion 510 is strictly smaller than the outer diameter of the middle portion 520, and the outer diameter of the middle portion 520 is strictly smaller than the outer diameter of the second end portion 530.

[0149] In the example shown, the stamping 500 includes a first rounded corner 512 at the connection between the first end portion 510 and the middle portion 520 , and a second rounded corner 523 at the connection between the middle portion 520 and the second end portion 530 .

[0150] refer to Fig.13 , the mold 600 has a generally cylindrical shape. The mold 600 has a first end 601 and a second end 602 opposite to the first end 601. The mold 600 also has a central orifice 650. The central orifice 650 is not open at the second end 602. The central orifice 650 leads to a cavity 660, which is open at the first end 601. A chamfer 610 is formed on the first end 601 around the mouth of the cavity 660. The cavity 660 has an inner diameter that is strictly larger than the inner diameter of the central orifice 650, so that a shoulder 665 is formed at the bottom of the cavity 660, at the junction of the cavity 660 and the central orifice 650.

[0151] Back to Fig.11, the die 600 is designed to receive the stamping 500. More specifically, the central aperture 650 of the die 600 and the second end portion 530 of the stamping 500 are sized so that the second end portion 530 can be inserted into the central aperture 650 through the mouth of the cavity 660. In addition, the second end portion 530 can slide in the central aperture 650 so that the stamping 500 and the die 600 can move relative to each other in a slidable manner. Therefore, the tip end 509 of the stamping 500 protrudes more or less relative to the inclined surface 610 of the die 600.

[0152] Fig.14 Shows that Fig. 7A The temporary positioning element 50 in the same position and the strake 21 placed on top of the temporary positioning element 50. Fig. 7A The other elements shown in Fig.14 Omitted to make the drawing easier to read. Fig.14 Also shown is a tool 400 being used to make the through holes 190 in the strake 21 .

[0153] The through hole 190 is produced using the tool 400 in the following manner.

[0154] First, the tool 400 is assembled by inserting the stamping 500 into the die 600. As mentioned above, the tip 509 of the stamping 500 is relative to the die 600. Fig.11 The chamfer 610 of the mold 600 is shown protruding. The tool 400 thus assembled is then positioned above the strake 21 , with the tip end 509 facing the strake 21 and positioned above the cavity 83 in the temporary positioning element 50 .

[0155] Next, a first impact is applied to the tool 400 in the direction of the strake 21 . Fig.14 The arrow 401 in FIG. 5 indicates the direction of the first impact. Under the action of the first impact, the tip end 509 punches the strake 21 and penetrates into the cavity 83 in the temporary positioning element 50. The tip end 509 and the first end portion 510 can also penetrate into the orifice 84 of the temporary positioning element 50 until the temporary positioning element 50 is formed. Fig.14 5. The stop position of the punch 500 shown. In this stop position, the first rounded corner 512 of the punch 500 abuts against the shoulder 83A located at the bottom of the cavity 83. This prevents the secondary insulating block 7 from being damaged by the tip 509 being driven too deep. In addition, the operator can confirm that the punch 500 has properly punched the column plate 21.

[0156] In a simplified variation, the intermediate portion 520 and the second fillet 523 are omitted from the stamping 500. Alternatively, the first fillet 512 and / or the second fillet 523 may be replaced by a shoulder.

[0157] When the stamping part 500 is in the Fig.14 In the illustrated stop position, a second impact is applied to the tool 400 in the direction of the strake 21 . Fig.14 The arrow 402 in the figure indicates the direction of the second impact. Since the punch 500 and the die 600 can move relative to each other in a sliding manner, under the action of the second impact, although the punch 500 abuts against the temporary positioning element 50, the die 600 still contacts the column plate 21. In addition, as Fig.14 As shown, the inner diameter of the cavity 660 of the mold 600 is strictly larger than the outer diameter of the head 82 of the temporary positioning element 60. Therefore, the inclined surface 610 contacts the strake 21 and generates the through hole 190 by partially shearing the strake 21. In addition, the shoulder 665 (see Fig.13 and Fig.14 ) can abut against the head 82. This prevents the secondary insulating block 7 or the column plate 21 from being damaged due to the mold 600 being driven too deep.

[0158] The first impact and the second impact may be applied to the tool 400 in a variety of ways. It may be convenient to apply the first impact and the second impact to the second end 602 of the mold 600 (see Fig.11 ) applies the first impact and the second impact, for example, by a hand tool such as a hammer, or by a pneumatic tool inserted into the second end 602. If necessary, the first impact and / or the second impact can be repeated.

[0159] It should be noted that the inner diameter of the cavity 660 may be only slightly larger than the outer diameter of the head 82, for example, 1 mm or 0.5 mm larger. Fig.14 The inner diameter of the cavity 660 does not need to be much larger than the outer diameter of the head 82, because the abutment of the stamping 500 and the temporary positioning element 50 tends to ensure that the cavity 660 is located in the center of the head 82. For this reason, it is preferred that the inner diameter of the central orifice 650 of the die 600 is only slightly larger than the outer diameter of the second end portion 530 of the stamping 500, for example 0.5mm or 0.25mm larger.

[0160] Back to Figure 4 , Figure 4A stud 200 is shown which is intended to be screwed into the positioning hole 40 in place of the temporary positioning element 50. The stud 200 has a collar 202 and a lower threaded portion 201 below the collar 202 which allows the stud 200 to be screwed into the positioning hole 40. The stud 200 also has an upper threaded portion 209 which makes it possible to retain the primary insulating block 22, as will be described further below. Above the collar 202 and below the upper threaded portion 209, the stud 200 has, from bottom to top: a section 203 having a diameter greater than the diameter of the section 209; a section 204 having a diameter equal to or slightly smaller than the diameter of the section 203, and having at least one flat surface so that a grip can be provided for a key or other tool for screwing the stud 200 into the positioning hole 40; and a non-threaded section 206 having a diameter substantially equal to the diameter of the upper threaded portion 209.

[0161] Figure 7B At the end of step 2005, the column plate 21 is Fig. 7A 1. A partial view in the direction of arrow B in FIG. The strake 21 has been pierced with a through hole 190, so the through hole 190 is shown in solid lines. The outline of the head 82 of the temporary positioning element 50 and the outline of the movable part 110 are also shown in FIG. Figure 7B In the figure, they are indicated with dotted lines because these elements are not visible through the strake 21.

[0162] In step 2006, a mark 195 is made on the column plate 21 (see Figure 7B ). The mark 195 is manufactured at a predetermined distance δ from the through hole 190. The mark 195 and the predetermined distance δ will be described in further detail below.

[0163] Since the strake 21 has a small thickness, it is preferred that the mark 195 does not affect the mechanical strength of the strake 21 and is therefore produced without cutting or notching the strake 21. For example, the mark 195 is made using a felt tip pen, indelible or otherwise.

[0164] In step 2007 , the temporary positioning element 50 is removed from the positioning hole 40 . More specifically, the temporary positioning element 50 is screwed out through the through hole 190 .

[0165] It is particularly advantageous that the internal thread of the orifice 84 has a thread direction opposite to the thread direction of the internal thread of the positioning hole 40. This makes it possible to use a threading tool, more particularly a cutting tool or other tool used in step 2005, so that the internal thread of the orifice 84 can be screwed only in the screwing-out direction 948 (see FIG. Fig. 7A) on the tool to screw out the temporary positioning element 50. For example, the internal thread of the orifice 84 is a left-hand thread, and the internal thread of the positioning hole 40 is a right-hand thread; of course, the opposite situation can also be imagined.

[0166] Still during step 2007 , the threaded portion 201 of the stud 200 is screwed into the positioning hole 40 through the through hole 190 from above the strake 21 , in place of the temporary positioning element 50 .

[0167] The predetermined distance δ is selected so that the stud 200 can be screwed into the positioning hole 40 through the through hole 190 without the collar 202 covering the mark 195. To this end, the predetermined distance δ can be such that the distance between the center of the through hole 190 and the mark 195 is greater than or equal to the radius of the collar 202.

[0168] Considering Figure 2 , Figure 4 and Figure 7B , and bearing in mind that the movable portion 110 is able to move in the direction 1001 shown in these figures, it will be appreciated that the markings 195 make it possible to visually convey the position of the movable portion 110 on the strake 21, even if the movable portion 110 is concealed by the strake 21. Specifically, the temporary positioning element 50 remains integral with the movable portion 110 as long as it is still screwed into the positioning hole 40 at the end of step 2003. Therefore, the position of the temporary positioning element 50 reflects the position of the movable portion 110, which can be manually adjusted before being screwed into the temporary positioning element 50 in step 2003, because the strake 21 has not yet concealed the movable portion 110 at this time.

[0169] Still considering Figure 2 , Figure 4 and Figure 7B It will be appreciated that since the predetermined distance δ is selected so that the stud 200 can be screwed into the positioning hole through the through hole 190 without the collar 202 obscuring the mark 195, then if the collar 202 does obscure the mark 195, the position of the stud 200 with the movable portion 110 is incorrect and must be corrected. Therefore, in step 2007, before the screwing-in of the stud 200 is completed, the mark 195 can be used as a visual reference for correctly positioning the movable portion 110 and the stud 200. More specifically, the stud 200 can be partially screwed in, then the position of the stud 200 can be adjusted relative to the mark 195, and then the screwing-in of the stud 200 can be completed, and when the screwing-in of the stud 200 is completed, the collar 202 is disposed against the strake 21.

[0170] In one example, when the screwing of the stud 200 is completed, the distance between the mark 195 and the outer contour of the collar 202 is between 0.1 mm (inclusive) and 4 mm (inclusive).

[0171] It should be noted that the marking 195 can be manufactured in different ways. Figure 7B As shown, the mark 195 can be a point mark such as a dot or a cross. Preferably, in this case, Figure 7B As shown, the mark 195 is positioned so that an imaginary straight line 198D passing through the center 199 of the through hole 190 and parallel to the direction 1001 also passes through the mark 195. It will be understood that in this case, the mark 195 can serve as a visual reference for positioning the stud 200 and the movable part 110 in the correct position, thereby allowing the movable part 110 to move in both directions of the direction 1001.

[0172] Alternatively, if Figure 7C As shown, the mark 195 may be a circle drawn around the through hole 190 at a distance δ from the through hole 190. The mark 195 intersects with the imaginary straight line 198D. It is understood that in this case, the mark 195 may also serve as a visual reference for positioning the stud 200 and the movable part 110 in the correct position, thereby allowing the movable part 110 to move in both directions of the direction 1001. Alternatively, although not shown, the mark 195 may be an arc or two arcs, preferably, the arc is an arc intersecting with the imaginary straight line 198D, preferably, the two arcs are two arcs each intersecting with the imaginary straight line 198D.

[0173] Alternatively, if Fig.7D As shown, the mark 195 can be a straight line segment drawn at a distance δ from the through hole 190 and perpendicular to the direction 1001. It will be understood that in this case, the mark 195 can also serve as a visual reference for positioning the stud 200 and the movable part 110 in the correct position, thereby allowing the movable part 110 to move in both directions of the direction 1001. Optionally, as Fig.7D As shown, the markings 195 may be diametrically opposed straight line segments relative to the center 199 of the through hole 190 , each straight line segment being drawn at a distance δ from the through hole 190 and perpendicular to the direction 1001 .

[0174] In any event, at the end of step 2007, the stud 200 is seated in the positioning hole 40 and the primary anchoring system 97 is thereby assembled.

[0175] In step 2008, the secondary sealing membrane 4 is welded to ensure the tightness of the secondary sealing membrane 4. To this end, the collar 202 is welded to the strake 21 in a sealing manner and the raised edge portion 32 of the strake 21 is welded to the welding flange 35 using known techniques.

[0176] In step 2009, one or more primary insulating blocks 22 are placed on the strake 21 and attached by the primary anchoring system 97. For example, such attachment may be achieved by a flat washer located on the segment 206, one (or more) Belleville washers, and a nut screwed onto the upper threaded portion 209.

[0177] Although steps 2001 to 2009 have been described above in the context of a single secondary insulating block 7, it will be appreciated that these steps may be repeated multiple times as the primary anchoring system 97 and secondary insulating blocks 7 are installed to assemble the wall of the tank 1. It will also be appreciated that the secondary insulating barrier 2 may include secondary elements other than the secondary insulating blocks 7 described above, particularly in certain specific areas, such as near the edge of the tank.

[0178] Next, in step 2010 , the construction of the wall of the tank 1 may be completed, in particular by assembling the primary sealing membrane 6 on the primary insulating barrier 5 .

[0179] Figure 8 A variant embodiment is shown. This variant embodiment differs from the previously described embodiment in that the temporary positioning element 50 does not have a non-threaded distal portion 63 and the secondary insulating block 7 does not have a blind hole 196. The temporary positioning element 50 and the steps of the method 2000 are otherwise the same as described above, so for the sake of brevity they will not be described again.

[0180] It will also be appreciated that the method 2000 is applicable to other types of secondary insulating elements used to form the secondary insulating barrier 2 besides secondary insulating blocks 7 .

[0181] Furthermore, the method 2000 is applicable when a recess for receiving the base 98 of the primary anchoring system 97 is formed at a position other than the center of the secondary insulating block 7 in the secondary insulating barrier 2. For example, the base 98 may be received in a recess formed in a corner region of one or more adjacent secondary insulating elements, or may be received in a recess formed between several adjacent secondary insulating elements.

[0182] Furthermore, the method 2000 may be applicable to other primary anchoring systems comprising a base received in a recess and a stud intended to be screwed into the base, and in particular, the method 2000 may be applicable to primary anchoring systems in which the base is a single plate.

[0183] For example, Fig. 9A variant embodiment is schematically shown in FIG. 3 , in which the base 398 of the primary anchoring system 397 is a plate provided with an internal threaded hole 340. The internal threaded hole 340 is sized to receive the threaded portion 201 (not shown) of the stud 200. Fig. 9 ) and the rod-shaped member 60 of the positioning element 50. The base 398 is received in a recess 395 formed in the secondary insulating barrier 2 between the outer edges of two or more adjacent secondary insulating elements 607 constituting the secondary insulating barrier 2. The recess 395 may also receive a secondary anchoring member for anchoring one or more secondary insulating elements 607 and / or may receive a seal made of a thermal insulating material, which is not shown in FIG. Fig. 9 Shown in.

[0184] The temporary positioning element 50 is the same as described above and therefore will not be described again for the sake of brevity.

[0185] The steps of method 2000 are the same as those described above, and therefore, for the sake of brevity, will not be described again. However, it should be noted that, since base 398 is a plate, step 2006 including making marks on column plate 21 can be omitted, because no marks are needed later to communicate the position of the movable part relative to base 398.

[0186] refer to Fig.10 , a partially cut-away view of a liquefied gas carrier 70 shows a sealed and thermally insulated tank 71 of a generally prismatic shape installed in a double hull 72 of the carrier 70. The wall of the tank 71 includes a primary sealing membrane intended to be in contact with the LNG contained in the tank, a secondary sealing membrane arranged between the primary sealing membrane and the double hull 72 of the carrier, and two thermally insulating barriers arranged between the primary sealing membrane and the secondary sealing membrane and between the secondary sealing membrane and the double hull 72, respectively.

[0187] The loading / unloading pipeline 73 arranged on the upper deck of the transport vessel can be connected to an offshore or port terminal in a manner known per se by means of appropriate connectors in order to transfer LNG cargo from or to the tank 71 .

[0188] Fig.10An example of an offshore terminal is shown, which includes a loading and unloading station 75, an underwater 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 hoses 79 that can be connected to the loading / unloading pipeline 73. The orientable movable arm 74 can be adjusted to accommodate liquefied gas carriers of all sizes. A connecting pipeline (not shown) extends into the tower 78. The loading and unloading station 75 allows the loading of a liquefied gas carrier 70 from the onshore facility 77 and the unloading of the liquefied gas carrier 70 to the onshore facility 77. The facility includes a liquefied gas storage tank 80 and a connecting pipeline 81, which is connected to the loading and unloading station 75 through an underwater pipeline 76. The underwater pipeline 76 allows the liquefied gas to be transported over long distances, for example 5 km, between the loading or unloading station 75 and the onshore facility 77, which enables the liquefied gas transport vessel 70 to be kept at a long distance from the coast during loading and unloading operations.

[0189] In order to generate the pressure required for transporting the liquefied gas, a pump on the transport vessel 70 and / or a pump attached to the onshore facility 77 and / or a pump attached to the loading and unloading station 75 is used.

[0190] Although the present invention has been described in conjunction with several specific embodiments, it is obvious that the present invention is by no means limited thereto and that the present invention includes all technical equivalents of the described means and combinations thereof if they fall within the scope of the present invention.

[0191] Use of the verb "comprise" or "include" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim.

[0192] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Claims

1. An assembly method (2000), the assembly method (2000) being used to assemble the wall of a sealed and thermally insulated tank for storing fluid, the wall of the tank (1) comprising in sequence in the thickness direction: A secondary insulating barrier (2) held on a supporting wall (3); a secondary sealing membrane (4) arranged to abut against the secondary insulating barrier (2); and a primary insulating barrier (5) arranged to abut against the secondary sealing membrane (4), the secondary sealing membrane (4) comprising metal strakes (21) welded in pairs, and the primary insulating barrier (5) comprising juxtaposed primary insulating elements (22); the assembling method (2000) comprising the following steps: a) assembling (2001) the secondary insulating barrier (2) on the supporting wall (3), the secondary insulating barrier (2) forming a supporting surface for the secondary sealing membrane (4), and the secondary insulating barrier (2) having a recess (197, 395) opening on the supporting surface; b) arranging (2002) an anchor system base (98, 398) in the recess (197, 395), the anchor system base (98, 398) comprising a positioning hole (40, 340) having a first internal thread; c) providing (2003) a temporary positioning element (50), the temporary positioning element (50) comprising a rod-shaped member (60) and a head (82) at one end of the rod-shaped member (60), the rod-shaped member (60) having a threaded portion (62), and the head (82) having a cavity (83) on the side opposite to the rod-shaped member (60), and screwing the temporary positioning element (50) into the positioning hole (40, 340) by means of the threaded portion (62); d) placing (2004) the strake (21) on top of the temporary positioning element (50) so that the head (82) locally deforms the strake (21); e) producing (2005) a through hole (190) in said strake (21) from above said strake (21) at said local deformation; f) removing (2007) the temporary positioning element (50) from the positioning hole (40, 340), and screwing a threaded stud (200) from above the strake (21) through the through hole (190) into the positioning hole (40, 340), the anchoring system base (98, 398) and the threaded stud (200) forming a primary anchoring system (97, 397); g) arranging (2009) one or more primary insulating elements (22) on the strakes (21) and attaching the one or more primary insulating elements (22) to the secondary insulating barrier (2) by means of the primary anchoring system (97, 397).

2. The assembly method (2000) according to claim 1, wherein: The strake (21) includes two raised edge portions (32) protruding toward the interior of the tank at two opposite ends of the strake (21), and the assembly method (2000) includes welding (2008) the raised edge portions (32) to a welding flange (35) that is mechanically retained on the secondary isolation barrier (2).

3. The assembly method (2000) according to any one of claims 1 and 2, wherein: The head (82) has at least one protruding edge portion (89) for locally deforming the strake (21).

4. The assembly method (2000) according to claim 2 in combination with claim 3, wherein: The temporary positioning element (50) is screwed into the positioning hole (40, 340) so that at least one of the protruding edge portions (89) is parallel to the raised edge portion (32).

5. The assembly method (2000) according to any one of claims 1 to 4, wherein: Step e) comprises punching said strake (21) by driving a punch (500) just into said cavity (83).

6. The assembly method (2000) according to any one of claims 1 to 5, wherein: The shaft (60) has an aperture (84) leading to the cavity (83) in the head (82), the aperture comprising a second internal thread, and wherein: - step e) comprises inserting a cutting tool into said cavity (83) and screwing said cutting tool into said orifice (84) of said shaft (60), then actuating said cutting tool; and - Step f) comprises using a tool to unscrew the temporary positioning element (50) from the positioning hole (40).

7. The assembly method (2000) according to claim 6, wherein: The first internal thread and the second internal thread have opposite thread directions, and step f) comprises applying rotation to a tool in the aperture (84) of the shaft (60).

8. The assembly method (2000) according to any one of claims 1 to 7, wherein: - the assembly method (2000) comprises, after step e) and before step f), a step e2), the step e2) comprising making (2006) a mark (195) on the strake (21) from above the strake (21), the mark (195) being positioned at a predetermined distance (δ) from the through hole (190); as well as - In step f), the threaded stud (200) is screwed into the locating hole (40, 340) using the marking (195) as a visual reference.

9. The assembly method (2000) according to claim 8, wherein: In step f), the threaded stud (200) is partially screwed into the positioning hole (40, 340), and then the position of the threaded stud (200) is adjusted relative to the mark (195), and then the threaded stud (200) is completely screwed into the positioning hole (40, 340).

10. The assembly method (2000) according to claim 8 or 9, wherein: The threaded stud (200) includes a collar (202), and in step f), the threaded stud (200) is screwed into the positioning hole (40, 340) without the collar (202) obscuring the mark (195).

11. The assembly method (2000) according to any one of claims 1 to 10, wherein: The recess (197) is formed in a secondary insulating element (7) of the secondary insulating barrier (2).

12. The assembly method (2000) according to claim 11, wherein: The recess (197) is formed to be spaced apart from an edge of the secondary insulating element (7).

13. The assembly method (2000) according to claim 12, wherein: The secondary insulating element (7) includes a blind hole (196) formed in the bottom of the recess (197) and leading to the recess (197), the rod-shaped member (60) includes a non-threaded distal portion (63) on the side opposite to the head (82), and in step c), the temporary positioning element (50) is screwed into the positioning hole (40, 340) with the aid of the threaded portion (62) until the non-threaded distal portion (63) is received in the blind hole (196).

14. The assembly method (2000) according to claim 13, wherein: The free end (64) of the non-threaded distal portion (63) is chamfered.

15. The assembly method (2000) according to any one of claims 11 to 14, wherein: The secondary insulating element (7) is a secondary insulating block, which comprises an insulating foam block (11) and a covering plate (10) placed on the insulating foam block (11), the upper surface of the covering plate (10) forming a supporting surface for the secondary sealing membrane (4), and wherein the recess (197) extends into at least a part of the thickness of the covering plate (10).

16. The assembly method (2000) according to claim 15, wherein: The anchor system base (98) comprises: - a movable part (110), the movable part (110) comprising a body (111), the body (111) having an upper surface (111A) flush with the upper surface of the cover plate (10), the positioning hole (40) passing through the body (111); and a retaining portion (120) attached to the cover plate (10) and interacting with the movable portion (110) so that the movable portion (110) stops in the recess (197) in the thickness direction; - The recess (197) and the retaining portion (120) are configured to allow the movable portion (110) to move perpendicularly to the thickness direction.

17. The assembly method (2000) according to claim 16, wherein: The recess (197) and the retaining portion (120) are configured to allow the movable portion (110) to move in a moving direction (1001) parallel to a longitudinal direction (1000) of the strake (21).

Images