CN111406176B

CN111406176B - Method for producing a thermal insulation barrier for a container wall and thermal insulation barrier produced thereby

Info

Publication number: CN111406176B
Application number: CN201880073660.9A
Authority: CN
Inventors: 迈克尔·亨利; 安托万·菲利普
Original assignee: Gaztransport et Technigaz SA
Current assignee: Gaztransport et Technigaz SA
Priority date: 2017-11-13
Filing date: 2018-11-09
Publication date: 2022-06-28
Anticipated expiration: 2038-11-09
Also published as: CN111406176A; FR3073600B1; ES2960534T3; RU2741688C1; EP3710742A1; KR102580155B1; KR20200088359A; MY196813A; EP3710742B1; FR3073600A1; SG11202004349WA; WO2019092384A1

Abstract

The invention relates to a method for manufacturing an insulating barrier (2, 5) of a wall (1) of a liquid-tight insulating tank incorporated in a supporting structure (3), said method comprising the steps of: -pushing said heat-insulating obturation member (44, 57, 58, 59, 60) against the load-bearing member (15, 82, 91) in the direction of the support structure (3) so as to irreversibly damage the heat-insulating obturation member (44, 57, 58, 59, 60, 95, 96) abutting against the load-bearing member (15, 82, 91), thereby irreversibly reducing the dimension of the heat-insulating obturation member (44, 57, 58, 59, 60, 95, 96) between the inner end (48, 61) of the heat-insulating obturation member (44, 57, 58, 59, 60) and the position of the heat-insulating obturation member (44, 57, 58, 59, 60) abutting against the load-bearing member (15, 82, 91), until the inner end (48, 61) of the heat-insulating obturation member (44, 57, 58, 59, 60, 95, 96) reaches a predetermined position in said opening (43, 55). The invention also relates to a thermal insulation barrier (2, 5) produced in this way.

Description

Method for producing a thermal insulation barrier for a container wall and thermal insulation barrier produced thereby

Technical Field

The present invention relates to the field of membrane liquid containment and insulation tanks for storing and/or transporting liquids such as cryogenic liquids.

Thin film liquid-tight thermally insulated tanks are particularly useful for storing Liquefied Natural Gas (LNG) stored at atmospheric pressure of about-162 c.

Background

Document WO2016046487 discloses a membrane-type liquid-tight thermally insulated storage tank. Each wall of the tank comprises a multilayer structure, which in the thickness direction from the outside of the tank to the inside of the tank is in turn: a secondary insulating barrier comprising insulating panels fixed to the support structure, a secondary sealing film abutting against the secondary insulating barrier, a primary insulating barrier comprising insulating panels abutting against the secondary sealing film, and a primary sealing film abutting against the primary insulating barrier and intended to come into contact with the liquefied natural gas contained in the storage tank. Each insulation panel of the primary insulation barrier has a cut-out along its edges and at its corners. The cutouts define openings that receive anchoring devices therein that secure the insulation panels of the primary insulation barrier to the insulation panels of the secondary insulation barrier. To ensure the continuity of insulation, an insulating closure member is received in an opening formed in the primary insulating barrier.

The dimensional tolerances of the heat-insulating closing member are small, so that the heat-insulating closing member fits the size of the opening as much as possible. Specifically, the size of the heat insulating and closing member and the size of the opening in the thickness direction of the tank wall must be matched to each other. In fact, if not, the level difference locally induced by the insulating and sealing member may affect the degree of flatness of the supporting surface of the primary sealing film. Currently, this level difference easily damages the primary sealing film.

A second feature is to limit the opening as much as possible in the direction perpendicular to the thickness, in order to limit the maximum gas movement phenomena that may affect the thermal performance.

Disclosure of Invention

The idea on which the invention is based is to propose a method for manufacturing a thermal insulation barrier intended to define an internal support face of a sealing membrane and containing an opening and a thermally insulating and closing member housed in said opening, which is easy to operate and limits the level differences in the internal support face of the sealing membrane in correspondence with the opening.

According to one embodiment, the present invention provides a method for manufacturing an insulation barrier for a wall of a liquid-tight, insulated storage tank incorporated in a support structure, the method comprising the steps of:

-anchoring a plurality of heat-insulating panels directly or indirectly to a supporting structure by means of anchoring means; said plurality of heat shields defining an inner support surface for the sealing membrane and having at least one open opening in a horizontal position on said inner surface;

-obtaining a polymer foam insulating closing member for ensuring continuity of insulation at the level of said opening, said insulating closing member having an inner extremity;

-inserting said heat-insulating closing member in said opening and pushing it towards the direction of the supporting structure until the heat-insulating closing member starts to abut against the carrying member housed in said opening in the direction of the supporting structure;

-pushing the heat-insulating obturation member against the carrier member in the direction of the support structure so as to irreversibly damage the heat-insulating obturation member against the carrier member, thereby irreversibly reducing the size of the heat-insulating obturation member between the inner end of the heat-insulating obturation member and the position of the heat-insulating obturation member against the carrier member, until the inner end of the heat-insulating obturation member reaches a predetermined position in the opening.

Thus, in this approach, the initial dimension of the insulating closure member in the thickness direction of the tank wall is no longer critical, as the insulating closure member irreversibly decreases in dimension in the thickness direction of the tank wall as it is pushed into the opening until the inner end of the insulating closure member reaches the desired position. In other words, the method enables the dimensions of the insulating closure member to be directly adjusted in the thickness direction of the tank wall during the incorporation of the insulating barrier onto the support structure. This makes it possible, on the one hand, to simplify the manufacturing operations of the heat-insulating and hermetically sealing member by increasing the dimensional tolerances thereof, and, on the other hand, to limit the amplitude of the level differences which can easily be formed in the inner supporting surface of the sealing membrane.

According to further advantageous embodiments, a method of the above-described type may have one or more of the following features.

According to one embodiment, the heat insulating and closing member has a density of 20 to 60kg/m³Between (20 and 60kg/m inclusive)³) Is made of the polymer foam of (1). Thus, this type of foam can be easily and irreversibly deformed by hand without the use of special tools.

According to one embodiment, the heat insulating and closing member is made of polyurethane foam.

According to another embodiment, the insulating and closing member is made of expanded polystyrene foam.

According to one embodiment, one of the anchoring devices is housed in the opening and comprises a carrier member against which the heat-insulating obturation member is pushed.

According to one embodiment, the anchoring means accommodated in the opening comprise a stud which is fixed directly or indirectly to the support structure, wherein during anchoring of a plurality of insulation panels, a locking member is mounted on the stud such that it cooperates with a locking region of at least one of the insulation panels so as to lock the insulation panel on the support structure, and wherein the stud forms a carrier member against which the insulation closing member is pushed such that the stud is embedded in the insulation closing member when the insulation closing member is pushed in the direction of the support structure.

According to one embodiment, the studs are embedded in the blocks of the heat insulating closing member at a distance of 5 to 30mm (including 5 and 30mm), for example between 8 and 15mm (including 8 and 15mm), when the heat insulating closing member is pushed towards the support structure.

According to one embodiment, an anchoring device is received within the opening, and wherein the insulating closure member has an outer end to which the housing is opened; the anchoring device is at least partially received in the housing when the inner end of the heat seal member reaches its predetermined position.

According to one embodiment, during the anchoring of the heat insulation panels, they are mounted on studs fixed directly or indirectly to the support structure:

-a stationary member;

-a nut for fixing the fixation member to the support structure; and;

-at least one elastic washer engaged on the stud, the elastic washer being located between the nut and the fixing member to generate an elastic force pressing the fixing member against the fixing region of the at least one insulating panel to fix said insulating panel to the supporting structure, the nut and the at least one elastic washer being housed in an opening opened at the level of the outer end of the insulating closing member when the inner end of the insulating closing member reaches its predetermined position.

According to one embodiment, the opening borders on the inner surface side an adjacent boundary surface, and wherein, in the predetermined position of the inner end of the thermo-insulating closing member, said inner end is located less than 1mm above and less than 3mm below said adjacent boundary surface.

Preferably, the inner end of the insulating closure member is flush with or at least 2mm below the level of the adjacent boundary surface at a predetermined position of the inner end of the insulating closure member.

According to one embodiment, after placing the heat insulating and closing member in a predetermined position, the adjacent boundary surfaces extend in the plane of the inner surfaces of the plurality of heat insulating panels or form the bottom of a recess in which the closing sheet is arranged.

According to one embodiment, the heat insulating closing member is irreversibly compressed in a thickness direction orthogonal to the support structure, where it abuts against the carrier member, when the heat insulating closing member is pushed in the direction of the support structure.

According to one embodiment, the heat insulating and closing member is larger in cross section than the opening portion and is tightly fitted in the opening. According to a variant embodiment, the heat-insulating closing member has an edge which is torn during the insertion of the heat-insulating closing member into the opening.

According to another embodiment, the invention also relates to an insulating barrier for a wall of a liquid-tight, insulated storage tank incorporated in a support structure, comprising:

-a plurality of insulating panels, directly or indirectly anchored to said supporting structure by anchoring means; said plurality of heat-insulating panels defining an inner support surface of the sealing membrane and further comprising at least one opening at the level of said inner surface; and;

-a polymer foam insulating and closing member inserted in said opening to ensure continuity of insulation; the heat-insulating closing member abuts against a carrying member accommodated in the opening in the direction of the supporting structure, characterized in that irreversible damage is caused to the heat-insulating closing member, where the heat-insulating closing member abuts against the carrying member, the irreversible damage being caused during pushing of the heat-insulating closing member towards the supporting structure until it reaches a predetermined position.

According to one embodiment, the invention also relates to a liquid-tight thermally insulated tank comprising a thermally insulating barrier as described above and a sealing membrane against said thermally insulating barrier.

The storage tank according to one of the aforementioned embodiments may form part of a land based storage arrangement, e.g. for storing LNG, or the storage tank may be installed in a coastal or deep water floating structure, in particular an ethane or methane tanker, a Floating Storage and Regasification Unit (FSRU), a Floating Production Storage and Offloading (FPSO) unit, etc. In the case of a floating structure, the storage tank may be used to receive liquefied natural gas, which is used as fuel to propel the floating structure.

According to one embodiment, a vessel for transporting liquids comprises a hull (e.g. a double hull) and one of the above-mentioned tanks arranged in the hull.

According to one embodiment, the invention also provides a method for loading and unloading a ship of the above-mentioned type, wherein liquid is supplied from a floating or land storage to the tanks of the ship or from the tanks of the hull to the floating or land storage through insulated pipes.

According to one embodiment, the invention also provides a liquid transfer system comprising the aforementioned vessel, an insulated pipe provided for connecting a tank mounted in the vessel to a floating or land storage means, and a pump for directing liquid from or to the tank of the vessel hull through the insulated pipe.

Drawings

The invention will be better understood and other objects, details, characteristics and advantages thereof will become more apparent during the course of the following description of several particular embodiments of the invention, given by way of non-limiting illustration only and with reference to the accompanying drawings.

Figure 1 is a perspective view in section of a tank wall according to a first embodiment.

Figure 2 shows a cross-section of an anchoring device able to fix the primary insulating panels of a primary insulating barrier to a secondary insulating barrier housed in an opening formed between two primary insulating panels and in an insulating closing member inserted in said opening.

Figure 3 is a cross-sectional view of the septum heat seal member of figure 2.

Figure 4 is a top view of the primary insulating panels formed at the level of the opening between two primary insulating panels, when the insulating closing member is housed in said opening and the closing sheet covers said opening.

Fig. 5 shows a cross-sectional view of an anchoring device which is accommodated in openings formed in the four corner regions of four adjacent primary insulation panels.

Figure 6 shows a schematic view of the anchoring device housed in the opening of the primary insulating barrier and in the insulating closing member, before the anchoring device is inserted in said opening, according to a variant embodiment.

Figure 7 is a schematic view similar to figure 6 during the insertion of the heat-insulating closing member into the opening.

Figure 8 shows a schematic view of the anchoring device housed in the opening and in the insulating containment member of the primary insulating barrier during its insertion into the opening, according to another variant embodiment.

Figure 9 is a perspective view in section of a wall of a tank according to a second embodiment.

Fig. 10 is a perspective view of the thermally insulating closure member of the primary thermally insulating barrier of the tank wall in fig. 9.

Figure 11 is a perspective view of the thermally insulating closing member of the secondary thermally insulating barrier of the tank wall in figure 9.

Figure 12 is a detail section of the anchoring device of the tank wall in figure 9.

Figure 13 is a schematic cross-section of a methane cruise ship tank comprising the tank wall shown in figure 1 and a quay for loading and unloading the tank.

Detailed Description

By convention, the terms "exterior" and "interior" are used to define the position of one element relative to another element corresponding to the interior and exterior of the tank.

In fig. 1, a multilayer structure of a wall 1 for a liquid-tight thermally insulated storage tank for storing, for example, Liquefied Natural Gas (LNG) is presented. Each wall 1 of the tank, in the thickness direction, from the outside of the tank to the inside of the tank is, in turn: a secondary insulating barrier 2 fixed to the support structure 3, a secondary sealing film 4 resting on the secondary insulating barrier 2, a primary insulating barrier 5 containing a liquid substance resting on the secondary sealing film 4, and a primary sealing film 6 for contact with the liquefied natural gas contained in the tank.

The support structure 3 may in particular be formed by a hull or double hull. The support structure 3 comprises a plurality of tank walls defining the main shape of the tank, which is typically polyhedral in shape.

The secondary thermal insulation barrier 2 comprises a plurality of secondary thermal insulation panels 7 anchored to the support structure 3, which are welded to the support structure 3 by resin beads (not shown) and/or studs (not shown). Each secondary insulating panel 7 comprises an insulating polymer foam layer sandwiched between a rigid inner panel and a rigid outer panel. The inner and outer sheets are, for example, plywood bonded to the insulating polymer foam layer. The insulating polymer foam may particularly be a polyurethane-based foam.

The secondary sealing film 4 comprises a plurality of corrugated metal sheets 10. Adjacent corrugated metal sheets 10 are overlap welded together. Further, the corrugated metal plate 10 is welded to a small metal plate 14 fixed to the inner plate of the secondary heat insulating plate 7. The corrugated metal sheet 10 comprises studs 15, which are fixed to the inner sheet of the secondary insulating panel 7 and are used to fix the primary insulating barrier 5 to the secondary insulating barrier 2, along its longitudinal edges and at its four corner cuts.

The primary insulating barrier 5 comprises a plurality of primary insulating panels 16, which are mostly rectangular. Each primary insulating panel 16 comprises a polymer foam layer 17 sandwiched between two rigid panels, namely an inner panel 18 and an outer panel 19. The inner panel 18 and the outer panel 19 are made of plywood, for example. The polymer foam layer 17 is, for example, polyurethane foam or reinforced with fibers such as glass fibers.

The inner panel 18 of each primary insulating panel 16 is provided with small metal plates 20, 21 for anchoring corrugated metal plates 22 of the primary sealing film 6. The small metal plates 20, 21 are secured in recesses formed in the inner plate 18 of the primary insulating panel 16, which may be secured in the recesses by, for example, screws, rivets or staples.

The primary sealing membrane 6 is assembled from a plurality of corrugated metal sheets 22. Each corrugated metal sheet 22 includes a plurality of flat surfaces 25 between the corrugations that press against the inner sheet 18 of the primary insulating sheet 16. In other words, the inner sheet 18 of the primary insulating panel 16 forms the inner support surface of the primary sealing film 6.

The corrugated metal sheets 22 of the primary sealing film 6 are arranged in an offset manner with respect to the primary insulating sheets 16, so that each of said corrugated metal sheets 22 jointly extends over four adjacent primary insulating sheets 16. The corrugated metal sheets 22 are lap welded together and along their edges to small metal sheets 20, 21 secured to the primary insulating sheet 16.

Each primary insulating panel 16 includes one or more cutouts 35 along each longitudinal edge thereof and cutouts 36 at each corner thereof. Each cut 35, 36 extends through the inner panel 18 and extends through the entire thickness of the polymer foam layer 17. At the level of each cut 35, 36, the outer panel 19 overhangs with respect to the polymer foam layer 17 and the inner panel 18, in such a way as to form a fixing region 37 cooperating with an anchoring device 38. Each of the cutouts 35 formed in the edge of one primary heat insulation board 16 is disposed facing the cutout 35 formed in the edge of the adjacent primary heat insulation board 16. Thus, the cutouts 35 of two adjacent primary insulation panels 16 form a pair of openings 43, the openings 43 receiving the anchoring devices 38 therein. Thus, a single anchoring device 38 can cooperate with two fixing areas 37 of the primary insulating panels 16 belonging respectively to one or other of two adjacent primary insulating panels 16. Further, each of the cutouts 36 formed at one corner of the primary heat insulation boards 16 faces the cutouts 36 formed at the adjacent corners of three adjacent primary heat insulation boards 16. The four cutouts 36 thus together form a cruciform opening 39. A single anchoring device 38 can then cooperate with the four contact faces 37 of four adjacent primary insulating panels 16.

Referring to fig. 2, it is seen that an opening 43 is formed at the level of the cut-outs 35 formed in the edges of two adjacent primary insulation panels 16, as well as the anchoring device 38 and the insulating closing member 44 accommodated in said opening 43.

The anchoring means 38 comprise studs 15 fixed to the inner panel of the secondary insulating panel 7. The anchoring device 38 also comprises a fixing member 40 fixed to said stud 15. The securing member 40 comes to rest against the securing region 37 of the primary insulating panel 16, i.e. against the region of the outer panel 19 that overhangs the inner panel 18 and the polymer foam layer 17. Thus, each fixing region 37 is sandwiched between the fixing member 40 and the secondary sealing film 4.

The fixing member 40 is herein an annular small metal plate comprising a hole mounted on the stud 15. The nut 41 fixes the fixing member 40 to the stud 15 in such a manner as to cooperate with the thread of the stud 15. Furthermore, in the illustrated embodiment, one or more resilient washers, such as belleville washers 42, are mounted on the studs 15 between the nuts 41 and the securing members 40, which enable the primary insulating panel 16 to be resiliently anchored to the secondary insulating panel 7.

To ensure the continuity of the insulation when the anchoring device 38 is placed in position, an insulating closing member 44 is placed in the opening 43.

In addition, as shown in fig. 2 and 4, the inner panel 18 of the primary insulation panel 16 is provided with a groove 45, the groove bottom 46 being adjacent to the opening 43. The groove 45 is used to accommodate the obturation plate 47 after the insulating obturation member 44 has been placed in the opening 43. The obturation plate 47 has an inner surface which is flush with the inner surface of the primary insulating plate 16 in such a way as to ensure the flatness of the support surface of the primary sealing film 6.

In another embodiment (not shown), the primary thermal insulation barrier 5 does not have the aforementioned groove 45 and obturation plate 47. Further, in this case, the inner end 48 of the heat insulating and closing member 44 is flush with the inner surface of the primary heat insulating board 16 in such a manner as to ensure the flatness of the supporting surface of the primary sealing film 6.

The insulating closure member 44 shown in figures 2 and 3 is made of a polymer foam. For example, a density of 20 to 60kg/m may be particularly useful for the insulating and sealing member 44³(containing 20 and 60 kg/m)³) Preferably between 30 and 50kg/m³(containing 30 and 50 kg/m)³) Polyurethane foam in between. Heat insulation seal with such characteristicsClosure member 44 is particularly advantageous in that irreversible deformation can be achieved without applying too much pressure. Alternatively, the heat insulating and sealing member 44 may also have a density of 20 to 60kg/m³(containing 20 and 60 kg/m)³) Between 30 and 50kg/m is particularly preferred ³(containing 30 and 50 kg/m)³) Expanded polystyrene in between.

The heat insulating and closing member 44 has a portion matching with the portion of the opening 43. In addition, the heat insulating and sealing member 44 has a planar inner end 48. The heat insulating closure member 44 also has an outer end 49, in which outer end 49 an outer shell 50 is open, which outer shell 50 is intended to at least partially house the anchoring device 38. More specifically, in the illustrated embodiment, the housing 50 has two

portions

51, 52 of different diameters. The first portion 51 has a larger diameter and opens at the level of the outer end 49 of the heat insulating closing member 44. The first portion 51 is intended to receive the elastic washer 42 and the nut 41. The second section 52 has a smaller diameter and extends from the first section 51 in a direction toward the inner end 48 of the insulating and containment member 44. The second portion 52 is adapted to receive the end of the stud 15. The geometry of the housing 50 is matched to the geometry of the anchoring device 38 in order to optimize the insulation in the opening 43.

As shown in fig. 3, in the initial state, before the heat-insulating and sealing member 44 is inserted into the opening 43, the heat-insulating and sealing member 45 has a dimension X in the thickness direction of the tank wall 1 between the bottom 53 of the outer shell 50 and the inner end 48 of the heat-insulating and sealing member 44 ₀. Dimension X₀Is larger than the dimension Y in the thickness direction of the tank wall 1 between the end of the stud 15 and the plane of the adjacent boundary surface bordering the opening 43.

In the embodiment shown, the adjacent boundary surface corresponds to the bottom 46 of the groove 45. In other words, the dimension Y herein corresponds to the distance between the end of the stud 15 and the bottom 46 of the groove 45. In other variant embodiments, when the primary insulation barrier 5 is devoid of containment plates 47 and the inner end 48 of the insulation containment member 44 is flush with the inner surface of the primary insulation panel 16, then the adjacent boundary surfaces correspond to the inner surface of the primary insulation panel 16. In other words, the dimension Y herein corresponds to the distance between the end of the stud 15 and the inner surface of the primary insulation board 16.

Advantageously, X₀Y + Δ, Δ is between 5 and 30mm (including 5 and 30mm), and preferably between 8 and 15mm (including 8 and 15 mm).

The operation of installing the heat insulating and closing member 44 in the opening 43 will be described in detail.

First, the insulating and closing member 44 is inserted into the opening 43 and then the opening 43 is pushed in towards the support structure 3 until said insulating and closing member 44, more specifically the bottom 53 of the casing 50, comes to rest against the load-bearing member, here the end of the stud 15. The insulating closure member 44 is then pushed against the stud 15 so that the stud 15 penetrates the polymer foam of the insulating closure member 44 and causes irreversible damage thereto. In other words, in the region of the heat insulation closing member 44 in contact with the stud 15, said heat insulation closing member 44 deforms beyond its elastic limit and suffers plastic deformation and/or breakage. Thus, the dimension X of the heat seal member 447 in the thickness direction of the tank wall 1 between the bearing area of the heat seal member 44 against the stud 15 and the inner end of the heat seal member 44 ₁Less than dimension X₀. According to one embodiment, the stud 15 is pressed into the block of insulating closure member 44 a distance of 5 to 30mm (including 5 and 30mm), for example a distance of 8 to 15mm (including 8 and 15 mm).

The predetermined position of the heat shield seal member 44 in the opening 43 corresponds to a position where the inner end 48 of the heat shield seal member 44 is positioned relative to an adjacent boundary surface, here the bottom 46 of the groove 45, which is less than 1mm above said adjacent boundary surface and less than 3mm below said adjacent boundary surface. The inner end 48 of the insulating and containment member 44 is preferably flush with or 2mm below the adjacent boundary surface. In other words, in the predetermined position of the heat-insulating and closing member, dimension X₁The following can be defined:

Y≥X₁more than or equal to Y-epsilon, wherein epsilon is 2 mm;

therefore, the above method makes it possible to reduce the magnitude of the level difference that is liable to be formed in the inner supporting face of the primary sealing film 6.

Fig. 5 shows the anchoring devices 54 and the openings 55 formed at the corners of four adjacent primary heat insulation boards 16, and the anchoring devices 54 are received in the openings 55. In this embodiment, the securing member 56 is X-shaped and includes four legs, each of which is received within a cutout 36 formed in a respective one of the primary insulating panels 16. The five heat-insulating and closing

members

57, 58, 59, 60 ensure continuity of heat insulation. Four insulating

containment members

57, 58, 59 (two of which are shown, one of which is fully shown in fig. 5) are all received in the cutout 36 of a respective primary insulating panel 16, while a fifth insulating containment member 60 is provided at the center of the opening 55 between the other four

insulating containment members

57, 58, 59, thereby acting as a wedge so that the other insulating

containment members

57, 58, 59 can be fixed in position.

For example, the materials of the heat insulating

seal members

57, 58, 59, 60 are the same as those of the heat insulating seal member 44 described with reference to fig. 2 to 4.

The operation of installing the heat-insulating and closing

members

57, 58, 59, 60 in the opening 55 will be described in detail. First, four heat insulating and sealing

members

57, 58, 59 are located in each slit 36 of one primary heat insulating board 16. According to a variant embodiment, the dimensions of the four insulating and

containment members

57, 58, 59 in the thickness direction of the tank wall 1 are matched to the dimensions of the openings, so that they do not need to be irreversibly damaged so that their inner ends 61 are flush with the inner surface of the adjacent primary insulating panel 16.

According to another variant embodiment, the dimensions of the four insulating and closing

members

57, 58, 59 in the thickness direction of the tank are greater than the dimensions in the thickness direction of the tank wall 1 between the supporting surface of the fixing member 56 for housing the outer ends of the insulating and closing members and the plane of the inner surface of the primary insulating panel 16. Furthermore, in this embodiment, in order to fit said insulating

obturation members

57, 58, 59 into the opening 55, each insulating

obturation member

57, 58, 59 is first inserted into the opening 55 towards the support structure 3 until said insulating

obturation member

57, 58, 59 comes to rest against a load-bearing member, here a handle of a fixed member. Each heat-insulating

containment member

57, 58, 59 is then pushed against fixing member 56, so that said heat-insulating

containment members

57, 58, 59 are compressed in an irreversible manner. Accordingly, the dimensions of each heat

seal closure member

57, 58, 59 are reduced in an irreversible manner until the inner end 61 of each heat

seal closure member

57, 58, 59 reaches a predetermined position, wherein the inner end 61 of each heat

seal closure member

57, 58, 59 is substantially flush with the inner surface of the primary insulating panel 16.

The central insulating seal member 60 is inserted into the opening 55 between the other four

insulating seal members

57, 58, 59 until it abuts the end of the stud 15. As shown in the embodiment of fig. 2 to 4, the insulating closing member 60 is then pushed against the stud 15, so that the stud 15 penetrates into the polymer foam of said insulating closing member 60 and damages it in an irreversible manner. The heat insulating and sealing member 60 is deformed until the inner end 61 of the heat insulating and sealing member 60 reaches a predetermined position.

Each predetermined position of the heat

shield closure members

57, 58, 59, 60 corresponds to a respective position at which the inner end 61 of the respective heat

shield closure member

57, 58, 59, 60 is less than 1mm above and less than 3mm, preferably less than 2mm below the adjacent boundary surface (here the inner surface of the primary insulating panel 16).

Figures 6 and 7 schematically illustrate a thermally insulating containment member 62 according to another embodiment. This embodiment differs from the embodiment described above with reference to fig. 1 to 4 in that, in the initial state, the heat insulating and closing member 62 has a size portion larger than the opening 43 portion. As shown in fig. 7, when the heat insulating and sealing member 62 is forcibly inserted into the opening 43, the outer edge 63 of the heat insulating and sealing member 62 is at least partially torn from the portion of the heat insulating and sealing member 62 inserted into the opening 43. This arrangement makes it possible to avoid a gap between the heat insulating and closing member 62 and the wall of the opening 43, thereby easily degrading the heat insulating performance.

For example, if the insulating and containment member 62 and the opening 43 are circular in cross-section, the insulating and containment member 62 has a diameter of 2 to 10mm, and advantageously 5 to 7mm, larger than the diameter of the opening 43. If the heat insulating and closing member 62 is of some other shape, for example a parallelepiped shape, at least one dimension of its cross section is greater than the corresponding dimension of the cross section of the opening 43.

According to a variant embodiment, the outer edge 63 of the insulating and closing member 62 may be pre-cut in such a way as to facilitate tearing of the insulating and closing member 62 when it is inserted into the opening 43.

As with the previous embodiment, the insulating seal member 43 is deformed against the stud 15 of the anchoring device until the inner end of the insulating seal member 62 reaches a predetermined position.

Fig. 8 schematically illustrates a thermally insulating containment member 64 according to another variant embodiment. As in the embodiment of fig. 6 and 7 described above, the heat insulating and closing member 64 has a size portion larger than the opening 43 portion. However, in this embodiment, the outer edge of the heat insulating and closing member 64 is not torn during the insertion of the heat insulating and closing member 64 into the opening 43, and the heat insulating and closing member 64 is fitted in the opening 43 in a tight-fitting manner.

In fig. 9, a multilayer structure of a tank wall 1 according to another embodiment is shown.

The secondary insulating barrier 2 includes a plurality of juxtaposed secondary insulating panels 65. Each secondary insulating panel 65 comprises a parallelepiped box, for example made of plywood, comprising a floor, a cover and a wall extending in the thickness direction of the wall 1 between the floor and the cover, which wall also defines a compartment filled with an insulating filler, for example perlite. The base plate projects laterally outwardly on two opposite sides of the box so that in each corner of the box, a batten 68 is secured to the projection.

The primary insulating barrier 5 also includes a plurality of juxtaposed primary insulating panels 66. The primary insulation panels 66 have a substantially similar structure to the secondary insulation panels 65. The primary insulation panels 66 have the same dimensions as the secondary insulation panels 65, except that they have different thicknesses in the thickness direction of the tank, and the tank thickness of the primary insulation panels may be less than the tank thickness of the secondary insulation panels 65. The base of the primary insulating panel is laterally outwardly extended at two opposite sides of the box so that in each corner of the box, a slat 67 is fixed to the projecting portion.

The secondary sealing film 4 comprises a continuous layer of metal base plate with raised edges. The raised edges of the base plate are welded to parallel welded supports that are secured into grooves formed in the cover plate of the secondary heat shield 65. The primary sealing film 6 has a similar structure and comprises a continuous layer of metal base plate with raised edges. The raised edges of the base plate are welded to parallel welded supports that are secured into grooves formed in the cover plate of the secondary heat shield 66.

For example, metal sole plates

The preparation method comprises the following steps: i.e. it is an alloy of iron and nickel, with a coefficient of expansion typically in the range 1.2X10^-6And 2X10^-6K^-1(including 1.2X 10)^-6And 2X10^-6K^-1)。

FIG. 12 shows an anchoring device 69 for anchoring the primary and secondary

heat shield panels

65, 66. The anchoring means 69 comprise a bush 82, which bush 82 is fixed to the supporting structure 3 at the level of the four corners of the four adjacent secondary heat insulating panels 66. Each bushing 82 receives a nut 83, and the lower end of the stud 84 is threaded into the nut 83. The anchoring device 69 also includes a fixing member 85 fixed to the stud 84. The securing member 85 abuts against the base plate 68 in such a way as to secure the secondary heat insulating plate 65 to the supporting structure 3. The nut 86 cooperates with the threads of the stud 84 in such a way as to fix the fixing member 85 to the stud 84. Furthermore, the anchoring means 69 comprise a resilient washer 87 mounted on the stud 84 between the nut 86 and the fixing member 85, which enables the secondary insulating plate 65 to be resiliently anchored to the support structure 3. The anchoring device also comprises a small plate 88 fixed to the fixing member 85. A spacing member 89, for example made of wood, is provided between the fixing member 85 and the small plate 88. The thickness of the spacer member 89 is such that the small plate 88 is flush with the cover plate of the secondary insulating board 65. The spacer member 89 includes a central housing for receiving the upper end of the stud 84, the nut 86 and the resilient washer 87. The spacer member 89 also includes holes through which bolts 90 have been passed for securing the small plates 88 to the fixing member 85.

In addition, the small plate 88 comprises a central threaded hole which receives the threaded seat of the stud 91. The studs 91 pass through holes formed through the base plate of the secondary sealing membrane 4. The stud 91 has a flange welded around the hole at its periphery to ensure the sealing of the secondary sealing membrane 4. The stud 91 has a threaded upper end onto which a nut 92 is screwed to clamp the securing member 93 to the base plate 67 of the primary heat shield 66. The anchoring means 69 further comprise at least one elastic washer 94, which elastic washer 94 is threaded on the stud 91 between the nut 92 and the fixing member 93, thus providing an elastic anchoring of the primary insulating plate 66 with respect to the small plate 88.

Returning to fig. 9, it can be seen that the primary and secondary

thermal barriers

5, 2 of the tank wall 1 having such a multilayer structure are also provided with thermal insulating

closure members

95, 96.

Fig. 11 shows the heat insulating closing member 95 of the secondary heat insulating barrier 2 in detail. Each insulating closing member 95 has a cross shape and includes an inner hole into which the stud 84 of the anchoring device 69 is inserted. The heat insulating and closing member 95 is inserted into the openings formed at the horizontal positions of the corners of the four secondary heat insulating panels 65 such that each of the four branches of the heat insulating and closing member 95 is inserted into the space between two adjacent secondary heat insulating panels 65.

According to one embodiment, the insulating seal member 95 is made of the same material as the insulating seal member 44 described with reference to figures 2-4. The following heat insulating and sealing member 95 is installed in the opening. The heat insulating closing member 95 is placed so that the studs 91 face the studs 84, and then the heat insulating closing member 95 is inserted into the opening towards the support structure 3 until it abuts against the load bearing part, here the bushing 82. The heat seal member 95 is then pushed against the liner 82 such that the heat seal member 95 is irreversibly deformed until the heat seal member 95 reaches a predetermined position. In this predetermined position, the inner end of the heat-insulating and sealing member 95 is substantially flush with the surface of the bottom plate 68 carried by the fixing member 85.

The insulating closure 96 of the primary insulating barrier 5 is shown in detail in fig. 10. Each insulating closure member 96 is inserted into openings formed at corner positions of four adjacent primary insulating panels.

According to one embodiment, the heat seal member 96 is made of the same material as the heat seal member 44 described with reference to FIGS. 2-4. The heat insulating and sealing members 96 are installed in the respective openings as follows. The heat insulating closing member 96 is placed in the housing and pushed in the direction of the support structure 3 until it abuts against the carrying member, here the stud 91. The heat seal member 96 is then pushed against the stud 91 such that the heat seal member 96 is irreversibly deformed until the heat seal member 96 reaches a predetermined position. At the predetermined location, the inner end of the insulating closure member 96 is substantially flush with the inner surface of the primary insulating panel 66.

Referring to fig. 13, a cross-sectional view of a methane tanker 70 shows a prismatic liquid-tight insulated tank 71 installed in the double hull 72 of the vessel. The walls of the tank 71 comprise a primary sealing membrane for 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 ship, and two thermal 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.

In a manner known per se, a loading/unloading pipe 73 provided on the deck of the ship's roof may be connected by means of adapted connectors to a marine or harbour terminal for transporting LNG cargo out of the storage tank 71 or for transporting LNG cargo to the storage tank 71.

Figure 13 shows an example of a marine terminal comprising a loading dock 75, a subsea pipeline 76 and a land device 77. Terminal 75 is a fixed offshore installation that contains a mobile arm 74 and a support 78 that supports mobile arm 74. The moving arm 74 carries a bundle of insulated hoses 79 which can be connected to the loading/unloading pipe 73. The directionally movable arm 74 is suitable for all methane tanker loading specifications. A connecting tube (not shown) extends within the support 78. The loading and unloading station 75 can load the methane tanker 70 from the ground facility 77 to the land facility 77 or unload the methane tanker 70 to the ground facility 77. The surface installation comprises a liquefied gas storage tank 80 and a connection pipe 81 connected to the terminal 75 through the underwater pipeline 76. The underwater pipeline 76 is capable of transporting liquefied gas over long distances (e.g., 5 kilometers) between the loading and unloading station 75 and the surface installation 77, which enables the methane tanker 70 to remain at a significant distance from the shore during loading and unloading operations.

The pump on the vessel 70 and/or the pump provided with the surface installation 77 and/or the pump provided with the loading and unloading station 75 are used to generate the pressure required for the transportation of the liquefied gas.

Although the invention has been described in connection with a number of specific embodiments, it is obvious that the invention is in no way limited to these embodiments and that the invention encompasses all such equivalent techniques and combinations of described means if they fall within the scope of the invention as defined by the claims.

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

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

Claims

1. A method for manufacturing an insulating barrier of a wall (1) of a liquid-tight, insulated storage tank incorporated in a support structure (3), the method comprising the steps of:

-anchoring a plurality of insulating panels directly or indirectly to said supporting structure (3) by means of anchoring means; said plurality of heat shields defining an inner support surface of the sealing membrane and having at least one open opening in a horizontal position of said inner support surface;

-obtaining a polymer foam insulating closure for ensuring continuity of insulation at the level of said opening, said insulating closure having an inner extremity;

-inserting the heat-insulating obturation member in the opening and pushing it towards the support structure (3) until it starts to abut against a load-bearing member housed in the opening in the direction of the support structure (3);

-pushing the heat-insulating obturation member against the load-bearing member in the direction of the support structure (3) so as to irreversibly damage the heat-insulating obturation member against the load-bearing member, thereby irreversibly reducing the dimension of the heat-insulating obturation member between the inner extremity of the heat-insulating obturation member and the position of the heat-insulating obturation member against the load-bearing member, until the inner extremity of the heat-insulating obturation member reaches a predetermined position in the opening.

2. The method of claim 1, wherein the insulating and closing member is made of polymer foam having a density of between 20 and 60kg/m 3.

3. Method according to claim 1 or 2, characterized in that the heat-insulating and pressure-tight element is made of polyurethane foam.

4. The method of claim 1 or 2, wherein one of the anchoring devices is received within the opening, and wherein the anchoring device comprises the carrier against which the insulating containment member is urged.

5. A method according to claim 4, wherein the anchoring means accommodated in the opening comprise studs directly or indirectly fixed to the support structure (3), wherein during anchoring of the plurality of heat insulation panels, a fixing and locking member is mounted on the studs such that it cooperates with a locking region (37) of at least one of the heat insulation panels to lock the heat insulation panel on the support structure (3), and wherein the studs form a carrier member against which the insulating and containment member is pushed such that the studs embed in the insulating and containment member when the insulating and containment member is pushed in the direction of the support structure (3).

6. Method according to claim 5, characterized in that the studs are embedded in the block of the heat-insulating containment member by a distance of 5 to 30mm (including 5 and 30mm) when the heat-insulating containment member is pushed in the direction of the support structure (3).

7. A method according to claim 1 or 2, wherein one of said anchoring devices is received in said opening, and wherein said thermally insulating closed member has an outer end (49) to which the housing (50) is opened; when the inner end of the heat-insulating and sealing member reaches its predetermined position, the anchoring means is at least partially housed in the casing (50).

8. Method according to claim 1 or 2, wherein the opening borders on an inner surface side an adjacent boundary surface, and wherein, in the predetermined position of the inner extremity of the thermo-insulating closing member, the inner extremity is located less than 1mm above and less than 3mm below the adjacent boundary surface.

9. Method according to claim 8, characterized in that after placing the heat insulating closing means in a predetermined position, the adjacent boundary surfaces extend in the plane of the inner surfaces of the heat insulating panels or form the bottom (46) of a recess (45) in which a closing sheet is arranged.

10. Method according to claim 1 or 2, characterized in that the heat-insulating closing member is irreversibly compressed in the thickness direction orthogonal to the support structure (3) when it is pushed in the direction of the support structure (3), where it abuts against the load-bearing member.

11. An insulating barrier for a wall (1) of a liquid-tight insulated tank incorporated in a supporting structure (3), comprising:

-a plurality of insulating panels, directly or indirectly anchored to said supporting structure (3) by anchoring means; the plurality of heat shields defining an inner support surface of the sealing membrane, further comprising at least one opening at a level of the inner support surface; and

-a polymer foam insulating closing member inserted in said opening to ensure continuity of insulation; the heat-insulating obturation member abuts against a load-bearing member housed in the opening in the direction of the support structure (3), characterized by irreversible damage to the heat-insulating obturation member, where it abuts against the load-bearing member, which is caused during the pushing of the heat-insulating obturation member towards the support structure (3) until it reaches a predetermined position.

12. A liquid-tight insulated storage tank comprising the insulating barrier of claim 11 and a sealing membrane against the insulating barrier.

13. A vessel (70) for transporting liquids, the vessel comprising a double hull (72) and a tank (71) according to claim 12.

14. A system for transporting a liquid, the system comprising a vessel (70) as claimed in claim 13, provided with an insulated pipe for connecting a tank (71) mounted in the vessel to a floating or land storage means (77), and a pump for conducting liquid from or to the tank of the vessel through the insulated pipe.

15. Method for loading and unloading a ship (70) according to claim 13, characterized in that liquid is supplied from the floating or land storage (77) to the tanks (71) of the ship or from the tanks of the ship hull to the floating or land storage by means of insulated pipes.