KR102475415B1 - sealed and insulated tank - Google Patents

Abstract

The present invention relates to a sealed and thermally insulating tank for storing a fluid, comprising a tank wall having an insulating barrier and a sealing membrane, the insulating barrier being parallelepiped shaped and having a bottom panel (25). ) and insulating linings 26, 28, the floor panel 25 forming a support surface 31, on which a wedge ) 32 is arranged, wherein at least one of the fixing devices 45 comprises a support member 33 configured to apply pressure on the wedge 32 in the direction of the support surface 31, wherein the wedge One of 32 and the bottom panel 25 has a larger thermal contraction coefficient than that of the fixing device 45 in the thickness direction of the tank wall, and the other of the wedge 32 and the bottom panel 25 One has a heat shrinkage coefficient smaller than that of the fixing device 45.

Description

sealed and insulated tank

The present invention relates to the field of sealed and thermally insulating tanks with membranes for storing and/or transporting fluids such as liquefied gas.

Sealed and insulated tanks with membranes are used in particular for the storage of liquefied natural gas (LNG), which is stored at approximately -163°C at atmospheric pressure. These tanks may be installed on land or floating structures. In the case of a floating structure, the tank may be for the transport of liquefied natural gas or for receiving the liquefied natural gas used as fuel to propel the floating structure.

Application WO2014/170588 discloses a sealed and insulated tank for the storage of liquefied natural gas integrated within the double hull of a ship. Each tank wall comprises a multi-layer structure, in the thickness direction, from the outside to the inside of the tank, a secondary insulating barrier held on a carrier structure, a secondary sealing membrane lying against the secondary insulating barrier, and a secondary sealing membrane lying against the secondary sealing membrane. It continuously has a primary thermal insulation barrier and a primary sealing membrane placed against the primary thermal insulation barrier and intended to be in contact with the liquefied natural gas contained in the tank.

In this document, the insulating barrier comprises a plurality of primary insulating panels, which are secured to the secondary insulating panels of the secondary insulating barrier using fasteners. All anchoring devices are provided with a stack of resilient washers which can ensure resilient anchoring of the primary insulation panel onto the secondary insulation panel. This resilient fixation permits slight relative movement of the primary insulation panels relative to the secondary insulation panels while allowing the primary insulation panels to be held against the secondary insulation panels. This allows the stresses that can be applied to the primary and secondary insulating panels in the fastening regions to be limited. However, such sealed tanks are not entirely satisfactory. In particular, these fasteners require a large number of stacks of Belleville washers, which increases the cost and complexity of manufacture of a tank equipped with such fasteners.

The concept on which the present invention is based involves providing a sealed and insulated tank in which anchoring of the insulated panels is carried out in a simpler and more economical way.

According to an embodiment, the present invention provides a sealed and thermally insulating tank for storing a fluid, comprising a tank wall, the tank wall comprising, in a thickness direction of the tank wall, a portion of the tank. continuous from the outside to the inside, a thermally insulating barrier intended to be fixed to a carrier structure and a sealing membrane supported against the insulating barrier;

The insulating barrier comprises insulating panels in the form of parallelepipeds placed side by side and intended to be fixed to the carrier structure, the insulating panels having a base plate and an insulating packing, the base plate from the insulating packing. forming a laterally protruding support surface, the support surface facing the inside of the tank, and a wedge disposed on the support surface, the wedge having an inner surface facing the inside of the tank;

anchoring devices intended to be fixed to the carrier structure between the insulating panels cooperate with the insulating panels, the anchoring devices being intended to hold the insulating panels relative to the carrier structure;

at least one of the securing devices comprises a support member having an outer surface facing the wedge, the support member being configured such that the outer surface bears against the inner surface of the wedge in the direction of the support surface;

one of the wedge and the base plate has a thermal contraction coefficient in the thickness direction greater than a thermal contraction coefficient of the holding device in the thickness direction of the tank wall, and the other of the wedge and the base plate has a thickness has a coefficient of heat shrinkage in the thickness direction that is smaller than a coefficient of heat shrinkage of the fixing device in the direction.

As a result of these features, an assembly formed from the base plate wedge has a heat shrinkage behavior close to that of a holding device. More specifically, the heat shrink behavior of this assembly allows the cooperation between the wedge and the support member to be maintained despite temperature changes. In other words, to maintain the support of the fixation device on the wedge, the assembly is prevented from contracting more than the fixation member. In this way, the cooperation of the support member and the wedge is maintained to maintain the fixation of the insulating panels on the carrier structure in a simple and reliable manner. In particular, the fixing device does not require the use of many resilient washers to keep the insulation panels fixed despite deformations of the carrier structure or deformations associated with heat shrinkage in the tank.

The coefficient of heat shrinkage of the fixing device is to be understood as the behavior in terms of heat shrinkage of all components of the fixing device in the region of the base plate and the wedge. In other words, this coefficient of heat shrinkage defines the heat shrinkage behavior of an assembly formed from the component(s) of the holding device over a portion of the holding device disposed in substantially the same thickness direction of the tank wall as the base plate and the wedge. The heat shrinkage coefficient of this fixture can be measured experimentally or calculated from knowledge of the different materials of construction of all elements forming the fixture.

According to other advantageous embodiments, such a tank may have one or more of the following features.

According to one embodiment, the thermal shrinkage coefficient of the wedge is smaller than that of the base plate.

According to one embodiment, the wedge and the base plate have respective dimensions in the thickness direction such that the support member is supported on the inner surface of the wedge in the direction of the support surface when the temperature decreases from ambient temperature. .

According to one embodiment, when the temperature changes from 20 ° C to -163 ° C, the dimensional change of the anchoring device in the thickness direction of the tank wall is a dimensional change in the thickness direction of the assembly formed of the base plate and the wedge. bigger than

In other words, in case of a temperature change within the tank, the outer surface of the support member moves more than the movement of the inner surface of the wedge in the thickness direction of the tank wall. In this way, the support of the support member on the wedge is maintained despite temperature changes in the tank.

According to one embodiment, at ambient temperature, the support member is supported on the wedge in the direction of the support zone.

According to one embodiment, the difference in the difference in size change in the thickness direction of the tank wall during the temperature change from 20 ° C to -163 ° C between the assembly formed of the fixing device and the base plate and the wedge is 5.50E -05 mm to 9.69E-02 mm. By convention, "EN" stands for 10 ^-N in this specification.

In other words, in the case of a temperature change from 20°C to -163°C in the tank, the movement of the outer surface of the support member compared to the movement of the inner surface of the wedge is a value of 5.50E-05 mm to 9.69E-02 mm. bigger than

According to one embodiment, the wedge is made of plywood and is configured to have fibers oriented in a plane parallel to the thickness direction of the tank wall.

According to one embodiment, the base plate is made of plywood and is configured to have fibers oriented in a plane perpendicular to the thickness direction of the tank wall.

According to one embodiment, the wedge has a coefficient of heat shrinkage in the thickness direction of the tank wall between 4E-06K ^-1 and 8E-06K ^-1 , for example 5.50E-06K ^-1 .

According to one embodiment, the base plate has a heat shrinkage coefficient in the thickness direction of the tank wall between 3E-05K ^-1 and 4E-05K ^-1 , for example 3.65E-05K ^-1 .

According to one embodiment, the holding device has a thermal shrinkage coefficient in the thickness direction of the tank wall between 1.4E-05K ^-1 and 1.8E-05K ^-1 , for example 1.6E-05K ^-1 .

According to one embodiment, in the thickness direction of the tank wall, the base plate has a thickness of 9 mm, and the wedge has a thickness of between 17.6 mm and 68 mm.

According to one embodiment, the wedge has a constant cross section in the thickness direction of the tank. According to one embodiment, the wedge lies on at least 50% of the supporting surface of the insulating panel.

According to one embodiment, the wedge is arranged on the supporting surfaces of two adjacent insulating panels such that the supporting member is supported on the wedge in the direction of the supporting surfaces of the two adjacent insulating panels.

According to an embodiment, the insulating barrier is a primary insulating barrier, the insulating panels are primary insulating panels, the sealing membrane is a primary sealing membrane, the supporting member is a primary supporting member, and the tank wall is the primary insulating barrier. and a secondary insulating barrier and a secondary sealing membrane intended to be interposed between the carrier structure.

According to one embodiment, at least one of the insulating panels extends in the thickness direction of the tank wall between a cover plate and the base plate and the cover plate, and is filled with insulating packing such as perlite. It includes carrier webs that define them.

According to one embodiment, at least one of the insulating panels includes a cover plate, the insulating packing is interposed between the base plate and the cover plate, and the insulating panel is disposed between the base plate and the cover plate. The insulating packing includes a first insulating polymer foam layer sandwiched between the base plate and the intermediate plate and a second insulating polymer foam layer sandwiched between the intermediate plate and the cover plate.

According to one embodiment, recesses are provided in the layers of insulating polymer foam and in the middle plate and cover plate, and the base plate protrudes with respect to the layers of insulating polymer foam and the middle plate and base plate to form the The support surface is provided on a base plate.

According to one embodiment, the secondary thermal insulation barrier comprises a plurality of secondary thermal insulation panels arranged side by side on the carrier structure, the tank comprising a plurality of fixing members intended to secure the secondary thermal insulation panels onto the carrier structure. include more

According to one embodiment, the primary insulation panels are placed on the secondary sealing membrane, and the fixing device is deployed from the secondary sealing membrane. According to one embodiment, the fixing device is fixed to the fixing member in the region of the secondary sealing membrane. In other words, both the fixing device and the base plate extend from the secondary sealing membrane in the thickness direction of the tank wall.

According to one embodiment, the first layer of insulating polymer foam has, at each of the corner regions of the insulating panel, a cut-oit accommodating a pillar extending between the base plate and the middle plate. This allows the creep and flattening of the foam to be limited.

According to one embodiment, the fluid is a liquefied gas, such as liquefied natural gas.

Such tanks are, for example, part of an onshore storage facility for storing liquefied natural gas, or a coastal or deep-sea floating structure, in particular a liquefied natural gas carrier, a floating storage and regasification unit (FSRU), a floating production, It can be installed in a storage and offloading facility (FPSO) and the like.

According to one embodiment, the present invention also provides a transport vessel for transporting cryogenic fluids, comprising a double hull and the aforementioned tank disposed within the double hull.

According to one embodiment, the double hull includes an inner hull forming the carrier structure of the tank.

According to one embodiment, the present invention also provides a method for loading and unloading such a transport vessel, wherein fluid is flowed via insulated piping from a floating or onshore storage facility to or from the tank of the transporter either floating or onshore. transferred to a storage facility.

According to one embodiment, the present invention also provides a transfer system for fluid, the system comprising insulated piping arranged to connect the above-described transport vessel, a tank installed in the hull of the transport vessel, to a floating or land storage facility. and a pump for propelling fluid through the insulated piping from a floating or land storage facility to a tank of the transport vessel or from a tank of the transport vessel to a floating or land storage facility.

With reference to the accompanying drawings, the invention will be better understood and other objects, details, features of the invention will be obtained from the following description of a number of specific embodiments of the invention, given purely as a non-limiting example. and advantages will be more clearly seen.
1 is a cut-away perspective view of a tank wall;
2 is a perspective view of a secondary insulation panel;
3 is a partial perspective view of a primary insulation panel;
4 is a perspective view of a fixing device for a primary insulation panel and a secondary insulation panel;
Fig. 5 is a partially exploded perspective view of the holding device of Fig. 4 integrated into the tank wall of Fig. 1;
Fig. 6 is a schematic perspective view of the detail of Fig. 5 showing a first embodiment of a retaining wedge of a primary panel;
Fig. 7 is a plan view of Fig. 5;
8 and 9 are schematic perspective and top views, respectively, of details of a second embodiment of a retaining wedge;
10 and 11 are schematic perspective and plan views of details of a third embodiment of a fixing wedge, respectively;
12 is a schematic cutaway view of a tank of a liquefied natural gas carrier and a loading/unloading terminal of the tank;
13 is a cut-away perspective view of a tank wall according to another embodiment;
FIG. 14 is an enlarged view of area XIII of FIG. 13 further showing a primary fixation member according to one embodiment.

By convention, the terms "external" and "internal" are used to define the position of one element relative to another element with respect to the inside and outside of the tank.

1 shows a multi-layer structure of a wall 1 of a sealed and insulated tank for storing a liquefied fluid, such as liquefied natural gas (LNG). Each wall 1 of the tank has, in the thickness direction, from the outside to the inside of the tank, a secondary thermal insulation barrier 2 held on a carrier structure 3, the secondary thermal insulation barrier 2 The secondary sealing membrane 4 leaning against, the primary insulating barrier 5 leaning against the secondary sealing membrane 4, and the primary sealing membrane 6 intended to come into contact with the liquefied natural gas contained in the tank are successively formed. to include

The carrier structure 3 may in particular be formed by a ship's hull or a double hull. The carrier structure 3 comprises a number of walls which form the general shape of the tank, generally in the form of a polyhedron.

The secondary thermal insulation barrier 2 comprises a plurality of secondary thermal insulation panels 7 anchored to the carrier structure 3 using anchoring devices 8 to be described in detail below. The secondary insulation panels 7 are generally parallelepiped and are arranged in parallel rows.

Referring to Fig. 2, the structure of a secondary thermal insulation panel 7 according to an embodiment is shown. The secondary insulation panel 7 comprises three plates in this example: a base plate 9 , a middle plate 10 and a cover plate 11 . The base plate 9, intermediate plate 10 and cover plate 11 are made of plywood, for example. The secondary insulation panel 7 also includes a first insulation polymer foam layer 12 sandwiched between the base plate 9 and the middle plate 10, and a second insulation polymer foam layer 12 sandwiched between the middle plate 10 and the cover plate 11. and an insulating polymer foam layer (13). The first and second insulating polymer foam layers 12 and 13 are adhesively bonded to the base plate 9 and the middle plate 10 and to the middle plate 10 and the cover plate 11, respectively. The insulating polymer foam may in particular be a foam based on polyurethane and optionally reinforced with fibers.

The first insulating foam layer 12 is cut-out in the corner area to allow the passage of corner pillars 14 . The corner posts 14 extend between the base plate 9 and the middle plate 10 in the region of the four corner regions of the secondary insulation panel 7 . The corner posts 14 are fastened to the base plate 9 and middle plate 10 and optionally to the insulating polymer foam 12 using, for example, staples or screws or adhesive bonding. The corner posts 14 are made of plywood or plastic material, for example. The corner pillars 14 allow part of the compressive load to be absorbed during operation and allow foam creep and flattening to be limited. These corner posts 14 have a different coefficient of heat shrinkage than the first insulating polymer foam layer 12 . Thus, when the tank cools down, the deflection of the secondary insulation panel 7 becomes smaller in the area of the corner pillars 14 than in other areas. This further increases the effect of changing the level or steps in the region of the corner regions of the secondary insulation panels 7 .

In addition, the secondary insulation panel 7 comprises recesses 15 , 16 in the region of the corner regions for accommodating anchoring devices 8 which will be presented in detail below. The secondary insulation panel 7 comprises a first recess 15 for allowing the rod 17 of the fixing device 8 to pass, from the base plate 9 to the intermediate plate 10. . The secondary insulation panel 7 includes a second recess 16 above the intermediate plate 10 . The second recess 16 has a larger dimension than the first recess 15 so that the intermediate plate 10 extends beyond the second insulating polymer foam layer 13 and the cover plate 11 . In this way, the intermediate plate 10 has, in the region of the corner zones of the secondary insulation panel 7, a support zone 18 intended to cooperate with the secondary support plate 19 of the fixing device 8. ) to form

Also, the cover plate 11 has a counterbore 20 in these four corner regions. Each counterbore 20 is for receiving a force dissipation plate 21 of a holding device 8 to be described below. The counterbores 20 have a thickness substantially similar to that of the force dissipation plate 21 such that the force dissipation plate 21 is flush with the top surface of the cover plate 11 . The cover plate 11 also includes grooves 22 for receiving weld supports.

The structure of the secondary insulation panel 7 has been described above as an example. Accordingly, in other embodiments, the secondary insulation panel 7 may have other general structures, for example the structure described in WO2012/127141. Thus, the secondary insulation panels 7 are manufactured in the form of a casing comprising a base plate, a cover plate and carrier webs, which are placed between the base plate and the cover plate to form a tank wall 1 ) and defines a number of compartments filled with insulating packing such as perlite, glass wool or rock wool.

In another embodiment, the secondary thermal insulation barrier comprises secondary thermal insulation panels 7 with at least two types of different structures depending on the bonding zone in the tank, for example the two structures mentioned above. In this way, in some areas of the tank wall 1, adjacent secondary insulation panels 7 are likely to have different behavior when subjected to a thermal gradient, which is There is a possibility of amplifying the phenomenon of level change between adjacent corners.

Returning to FIG. 1 , the secondary sealing membrane 4 comprises a continuous sheet of metal strakes 23 with raised edges. The strakes 23 are welded via raised edges to parallel welding supports fixed in grooves 22 provided in the cover plates 11 of the secondary insulation panels 7 . The strakes 23 are, for example, made of Invar®: an alloy of iron and nickel with an expansion coefficient typically between 1.2x10 ^-6 and 2x10 ^-6 K ^-1 .

The primary thermal insulation barrier 5 comprises a plurality of primary thermal insulation panels 24 secured to the carrier structure 3 using the fixing devices 8 described above. The primary insulation panels 24 generally have a parallelepiped shape. Moreover, the primary insulating panels 24 have the same dimensions as the secondary insulating panels 7 except for the thickness in the thickness direction of the tank wall 1, the thickness of the primary insulating panels being equal to the thickness of the secondary insulating panels. It can be different, in particular less than the thickness of the secondary insulation panels. Each of the primary insulating panels 24 is arranged in line with one of the secondary insulating panels 7 and aligned together in the thickness direction of the tank wall 1 .

Referring to FIG. 3 , the structure of a primary thermal insulation panel 24 according to an embodiment is shown. The primary insulation panel 24 has a multilayer structure similar to the secondary insulation panel 7 of FIG. 2 . Thus, the primary insulating panel 24 successively comprises the base plate 25, the first insulating polymer foam layer 26, the middle plate 27, the second insulating polymer foam layer 28, and the cover plate 29. include The insulating polymer foam may in particular be a foam based on polyurethane and optionally reinforced with fibers.

The primary insulating panel 24 is such that the base plate 25 extends beyond the first insulating polymer foam layer 26, the middle plate 27, the second insulating polymer foam layer 28 and the cover plate 29. , recesses 30 in the region of the corner zones. In this way, the base plate 25 forms a support region 31 in the region of the corner regions of the primary insulating panel 24 . This support section 31 houses a wedge 32 which will be described in more detail below. In the embodiment shown in FIG. 3 , the wedge 32 has a similar shape to the support section 31 . This wedge 32 is intended to cooperate with the primary support plate 33 of the fixing device 8 .

The base plate 25 includes grooves 34 intended to receive the raised edges of the secondary sealing membrane 4 . In the embodiment shown in Figures 1 and 3, the cover plate 29 includes grooves 35 for receiving weld supports (not shown).

The structure of the primary insulation panel 24 has been described above as an example. Thus, in another embodiment, the primary thermal insulation panels 24 may have a different general structure, for example described in document WO2012/127141.

In another embodiment, the primary thermal insulation barrier 5 comprises primary thermal insulation panels 24 with at least two types of different structures, for example the two structures mentioned above, depending on the bonding zone in the tank.

Returning to FIG. 1 , the primary sealing membrane 6 comprises a continuous sheet of metal strakes 36 with raised edges. The strakes 36 are welded via raised edges to parallel welding supports fixed in grooves provided in the cover plates 29 of the primary insulating panels 24 . Although described in the context of a primary sealing membrane 6 manufactured using metal strakes 46 , the primary sealing membrane may be manufactured according to other techniques. For example, the primary sealing membrane may be made using undulating metal plates, as described for example in document FR2691520.

As shown in FIG. 1 , the fixing devices 8 are arranged in the region of the four corners of the primary insulating panels 24 and the secondary insulating panels 7 . Each stack of secondary insulation panels 7 and primary insulation panels 24 is secured to the carrier structure 3 using four fasteners 8 . Furthermore, each anchoring device 8 cooperates with the corners of four adjacent secondary insulating panels 7 and the corners of four adjacent primary insulating panels 24 .

Referring to Figures 4 and 5, the structure of the fixing device 8 is shown.

The fixing device 8 comprises a socket 37, the base of which is positioned corresponding to an undercut in the region of the corner regions of the four adjacent secondary insulation panels 7. is welded to the carrier structure 3 in The socket 37 receives a nut (not shown) into which the lower end of a rod 17 is screwed.

The rod 17 extends through a hole provided in an insulating stopper 38 to ensure the continuity of the secondary insulation in the area of the fixing device 8 . The insulating stopper 38 has a cross-section formed by four branches along a plane perpendicular to the thickness direction of the tank wall 1 . Each of the four branches is inserted into a gap provided between two of the four adjacent secondary insulation panels 7 .

The fixing device 8 abuts the support area provided on each of the four adjacent secondary insulation panels 7 to hold the secondary insulation panels 7 relative to the carrier structure 3 of the carrier structure 3. It further includes a secondary support plate 19 supported in the direction. In the illustrated embodiment, the secondary support plate 19 is accommodated in a second recess 16 provided in the second thermal insulation polymer foam layer 13 of each of the secondary thermal insulation panels 7, and the support region 18 It is supported in contact with the region of the intermediate plate 10 forming the.

To ensure retention of the secondary support plate 19 on the rod 17, a nut 39 cooperates with a thread provided in the region of the upper end of the rod 17.

In the illustrated embodiment, the fixing device 8 further comprises one or more resilient washers 40 of the Belleville type. The elastic washers 40 are coupled on the rod 17 between the nut 39 and the secondary support plate 17, which enables elastic fixation of the secondary insulation panels 7 on the carrier structure 3 let it Also, to hold the nut 39 in place on the rod 17, advantageously a locking mamber 41 is locally welded to the upper end of the rod 17.

The fixing device 8 further includes a force dissipation plate 21 , an upper plate 42 , and a spacer 43 , which are fixed to the secondary support plate 19 .

The force dissipation plate 21 is accommodated in each of counterbores 20 provided in the cover plates 11 of the four adjacent secondary insulation panels 7 . Thus, the force distribution plate 21 is located between the cover plates 11 of each of the four secondary insulating panels 7 and the secondary sealing membrane 4 . The force dissipation plate 21 is for mitigating a phenomenon in which a level changes between corners of adjacent secondary insulation panels 7 . Thus, the force dissipation plate 21 enables stresses that may be applied to the secondary sealing membrane 4 and the primary thermal insulation panels 24 to be distributed in-line with the corner regions of the secondary thermal insulation panels 7 . As a result, the force dissipation plate 21 causes a phenomenon of punching of the base plates 25 of the primary thermal insulation panels 24 in-line with the corner sections of the secondary thermal insulation panels 7 and the primary thermal insulation panels. puncture and settlement of the insulating polymer foam layers 26, 28 of (24) can be limited.

The force dissipation plate 21 is advantageously made of stainless steel, an alloy of iron and nickel such as invar having an expansion coefficient typically between 1.2x10 ^-6 and 2x10 ^-6 K ^-1 , and an expansion coefficient of 2x10 ^- It is made of a metal selected from alloys of iron and manganese with a K of less than ⁵ K ^-1 , typically approximately 7x10 ^-6 K ^-1 . The force dissipation plate 21 has a thickness between 1 and 7 mm, preferably between 2 and 4 mm, for example approximately 3 mm. The force distribution plate 21 advantageously has the shape of a square with a side dimension between 100 and 250 mm, for example approximately 150 mm.

The top plate 42 is disposed below the force dissipation plate 21 and has dimensions smaller than those of the force dissipation plate 21 so that the force dissipation plate 21 completely covers the top plate 42 . The top plate 42 is in-line with the supporting regions 17, in recesses 16 provided in the corner regions of the secondary insulating panels 7, ie in the embodiment shown in FIG. 5, secondary thermal insulation. It is received in recesses 16 provided in the second insulating polymer foam layer 13 of the panels 7 .

The top plate 42 has a threaded hole 44 into which a threaded base of pins 45 for fixing the primary insulating panels 24 is mounted. In order to allow the pin 45 to be fixed to the top plate 42, the force dissipation plate 21 also includes a hole provided opposite to the threaded hole of the top plate 42, whereby the pin (45) can extend through the force dissipation plate (21).

The upper plate 42 extends parallel to the thickness direction of the tank wall 1 connecting the two wide opposing surfaces of the wall 1 parallel to the carrier structure 3 and connecting the two wide opposing surfaces. It has an overall rectangular parallelepiped shape with four faces. In the embodiment shown in FIG. 4 , four faces extending parallel to the thickness direction of the tank wall 1 are connected by fillets 46 . This makes it possible to avoid the existence of an acute angle while limiting the concentration of stress and contributes to further limiting the perforation phenomenon of the base plates 25 of the primary insulation panels 25 .

In one embodiment, the top plate 42 and the force dissipation plate 21 are formed as a single integral element.

The spacer 43 is disposed between the secondary support plate 19 and the upper plate 42 and serves to maintain a gap between the secondary support plate 19 and the upper plate 42 . In the embodiment shown in FIG. 4 , the spacer 43 has chamfers 47 in order to fall within the spatial requirements of the top plate 42, as viewed in the thickness direction of the tank wall 1. have In other words, the top plate 42 completely covers the spacer 43 .

In the embodiment shown in FIG. 5 , the fixing device 8 is similar to FIG. 4 in that the spacer 43 has, in a plane perpendicular to the thickness direction of the tank wall 1, a cross-section without any chamfers. It differs from the illustrated fixing device 8, which can facilitate the manufacture of the spacer 43. In a similar manner (not shown), the top plate 42 may not have any fillets.

The spacer 43 is advantageously made of wood, which allows a thermal bridge towards the carrier structure 3 in the area of the anchoring device 8 to be limited. The spacer 43 is in the shape of an inverted U to form a central housing 48 between the two branches of the U. The central housing 48 accommodates the upper end of the rod 17, a locking member 41, a nut 39, and elastic washers 40. The spacer 43 is also received in a recess 16 provided in-line with the support surface 18.

The locking member 41 has a square or rectangular shape in which the diagonal has a dimension greater than the dimension of the center housing 48 between the two branches of a U, which blocks rotation of the rod 17 relative to the spacer 43. and thus preventing the rod 17 from being separated from the nut 39.

In order to fix the force dissipation plate 21, the top plate 42, the spacer 43, and the secondary support plate 19 to each other, the above-mentioned elements each have two holes, and the two holes Screws 49 and 50 extend through each. In order to ensure fixation of the aforementioned elements to each other, the holes provided in the secondary support plate 19 each have a threaded portion cooperating with one of the screws 49 and 50 .

Further, the pin 45 extends through a drill hole provided to penetrate the strake 23 of the secondary sealing membrane 4 . The pin 45 has a collar 51 welded to the periphery of the pin 45, around the drill hole, to ensure sealing of the secondary sealing membrane 4. Thus, the secondary sealing membrane is sandwiched between the collar 51 of the pin 45 and the force dissipation plate 21 .

The fixing device 8 also comprises a primary support plate 33 supported on a wedge 32 in the direction of the carrier structure 3 . In the embodiment shown in FIGS. 3 and 5 , the corners of each primary insulating panel 24 include a respective wedge 32 , which wedge 32 comprises a support area 31 formed by the base plate 25 . ) to cover In this way, the primary supporting plate 33 presses the wedges 32 of four adjacent primary insulating panels 24 to hold the primary insulating panels 24 against the carrier structure 3, The wedge 32 is supported against and against support regions 31 provided in corresponding corners of four adjacent primary insulating panels 24 . In the illustrated embodiment, each support section 31 is formed by a protruding portion of the base plate 25 of one of the primary insulating panels 24 . The primary support plate 33 is received in recesses 30 provided in the corner regions of the primary insulating panels 24 in-line with the support regions 31 .

To ensure the fastening of the primary support plate 33 to the pin 45, a nut 52 cooperates with a thread provided in the region of the upper end of the pin 45. In the illustrated embodiment, the fixing device 8 further comprises a single resilient washer 53 of the Belleville type, which is coupled to the pin 45 between the nut 52 and the primary support plate 33 .

In addition, an insulating stopper 54 shown in FIG. 5 is provided in the corner area of four adjacent primary insulating panels 24 to ensure the continuity of the primary insulating barrier 5 in the area of the fixing device 8. It is inserted over the fixing device 8 in recesses 30 provided in the region of the . In addition, a closing plate made of wood (not shown) allows the flatness of the bearing surface of the primary sealing membrane 6 to be ensured. The closure plate is received in counterbores provided in the region of the corner regions of the primary insulating panels 24 .

In order to maintain the fixation of the primary insulating panels 24 on the carrier structure 3, the primary support on the wedges 32 despite the difference in the behavior of the fixing device 8 and the primary insulating panels 24 It is necessary to maintain the support of the plate 33. In particular, it is necessary to maintain this support despite the difference in behavior in terms of heat shrinkage of the fixing device 8 and the primary insulation panels 24 .

To maintain the support of the primary support plate 33 on the wedges 32, the embodiment shown in FIG. 5 provides for the use of wedges 32 and a base plate 25, which are thicker than the tank wall. direction, and the assembly formed by the base plate 25 and the wedge 32 is configured to have an overall thermal shrinkage coefficient smaller than that of the fixing device 8. In the remainder of the description, reference to heat shrinkage coefficient refers to the heat shrinkage coefficient in the thickness direction of the tank wall.

In the context of a base plate 25 made of a material having a heat shrinkage coefficient greater than that of the fins 45 and the primary support plate 33, the wedge 32 is the thermal contraction coefficient of the fins 45 and the primary support plate 33. It is selected to have a heat shrinkage coefficient smaller than the heat shrinkage coefficient. In addition, the base plate 25 and the wedge 32, the assembly formed by the base plate 25 and the wedge 32 is smaller, preferably slightly smaller than the total heat shrinkage coefficient of the pin 45 and the primary support plate 33 They are sized to have a small, ideally equal, overall coefficient of thermal shrinkage. In this way, support of the outer surface of the primary support plate 33 on the inner surface of the wedge 32 is maintained in case of temperature changes in the tank.

This is, as a result of the fact that the assembly formed by the base plate 25 and the wedge 32 has an overall thermal contraction coefficient smaller than that of the pin 45 and the primary support plate 33, under the action of a temperature change, the primary This is because the movement of the outer surface of the support plate 33 is slightly greater than the movement of the outer surface of the wedge 32, ideally substantially equal to the movement of the outer surface of the wedge 32.

Thus, this heat shrinkage behavior is such that the support of the primary support plate 33 on the wedge 32 will be maintained in a reliable and stable manner despite the absence or limited number of Belleville washers 50 on the pin 45. make it possible

In one example, the base plate 25 of the primary insulating panels 24 is made of plywood with a thickness of 9 mm and fibers oriented in a plane parallel to the carrier structure 3 . Accordingly, this base plate 25 has a thermal contraction coefficient of approximately 3.65E-05. In the context of fin 45 having a coefficient of thermal shrinkage of approximately 1.60E-05, the wedge 32 may be manufactured to have a coefficient of thermal shrinkage of approximately 5.50E-06.

This wedge 32 is for example made of plywood, but in contrast to the base plate 25, the fibers of the plywood are perpendicular to the porous structure, ie in a plane parallel to the thickness direction of the tank wall. Oriented.

In this example, the wedge 32 has a thickness greater than 17.6 mm, and the pin 45 and primary support plate 44 are such that the outer surface of the primary support plate 33 is 26.6 mm from the outer surface of the base plate. It is given a size to position. This means that, in this example, at a temperature change of 90° C., the difference in movement between the outer surface of the primary support plate 33 and the inner surface of the wedge 32 is approximately 2.70E-05, and the wedge ( This is because the outer surface of the primary support plate 33 moves slightly more than the inner surface of the wedge 32 so that the support of the primary support plate 33 on 32 is maintained. In the same way, at a temperature change of 183° C., the difference in movement between the outer surface of the primary support plate 33 and the inner surface of the wedge 32 is approximately 5.49E-05, and the wedge 32 despite the temperature change The outer surface of the primary support plate 33 moves slightly more than the inner surface of the wedge 32 so that the support of the primary support plate 33 on the surface is maintained.

The pins 45 and the primary support plate 33 are dimensioned such that the thickness of the wedge 32 is 18, 19 or 20 mm and the outer surface of the primary support plate is at a distance of 27, 28 or 29 mm respectively. ) so that the locking of the primary support plate 33 can be maintained.

However, in order not to damage the wedge 32 and/or the base plate 25, the assembly formed by the base plate 25 and the wedge 32 is secured by the pin 45 and the primary support plate 33. It should not have an overall shrinkage coefficient that is too different from the heat shrinkage coefficient of the formed assembly. This is because an excessively large difference in the coefficient of heat shrinkage can lead to displacement and thus an excessively high support of the primary insulating plate 33 on the wedge 32 .

In this way, the base plate 25 of 9 mm thick plywood, given as an example above, has a heat shrinkage coefficient of 3.65E-05, and the fins 45 have a heat shrinkage coefficient of 1.60E-05, in the example of 5.50E-05. A wedge 32 with a heat shrinkage coefficient of 05 should not have a thickness greater than 68 mm due to the risk that the primary support plate 33 exerts an excessively strong support. In other words, in this embodiment, the wedge 32 must have a thickness between 17.6 mm and 68 mm to maintain support of the primary support plate 33 without damaging the base plate 25 .

In this manner, the wedge 32 is made of a material selected and/or constructed to obtain a wedge 32 having a coefficient of heat shrinkage that is less than that of the base plate 25 on which the wedge 32 rests in the thickness direction of the tank wall. is made Moreover, this wedge 32 is formed in the thickness direction of the tank wall so that the assembly formed by the base plate 25 and the wedge 32 has a thermal contraction behavior close to that of the holding device 8. size is given. More specifically, the heat shrinkage behavior of this assembly allows the cooperation between the wedge 32 and the primary support plate 33 to be maintained despite temperature changes, i.e. the assembly shrinks more than the fixing device 8 prevent becoming

FIG. 6 shows a manufacturing variant of a wedge 32 , wherein the wedge 32 is sized so as to cover together two supporting regions 31 of two adjacent primary insulating panels 24 . This wedge 32 allows assembly operations to be confined within the tank, thus facilitating the manufacture of the tank. The wedge 32 has a central recess 55 through which a pin 45 can pass.

7, this wedge 32 is sized to preserve a space between the first insulating polymer foam layer 26 and the wedge 32, which allows circulation of gases within the primary insulating barrier. makes it possible In other words, the wedge 32 is inert in the primary insulating barrier, ensuring sufficient cooperation with the primary supporting plate 33 and with the supporting sections 31 to allow fixing of the primary insulating panels 24 . It is dimensioned not to completely cover the supporting regions 31 of adjacent primary thermal insulation panels 24, in order to preserve a space allowing the circulation of gases, such as gas.

8-11 show other embodiments of a wedge 32 that allows circulation of gas within the primary insulating barrier by providing a space between the wedge 32 and the first insulating polymer foam layer 26 .

13 shows a tank wall 101 according to a second embodiment. Elements identical or similar to those of FIGS. 1 to 11 have the same reference numerals increased by 100, and will be described only in different cases.

The embodiment shown in FIGS. 13 and 14 differs from the embodiment shown in FIGS. 1 to 5 in that the primary insulating panels 124 overlap in an offset manner with respect to the secondary insulating panels 107 . In this way, the corner sections of the primary insulating panels 124 are not arranged in-line with the corner sections of the secondary insulating panels 107, but instead of the cover plate 111 of the corresponding secondary insulating panels 70. It is placed in line with the center.

In the illustrated embodiment, the primary insulating panels 124 are offset relative to the secondary insulating panels 107 in two directions of a plane half the length of the secondary insulating panels 107 . The size of the offset can be different, the corner regions of the primary insulation panels 124 can be elsewhere on the cover plate 111 of the secondary insulation panel 107, but preferably the rise of the strakes 123 away from these edges so as not to interfere with the The magnitude of the offset can be different in the two directions of the plane.

Further, in the embodiment shown in FIGS. 13 and 14 , the secondary insulation panels 107 and the primary insulation panels 124 described above in that they do not include the intermediate plates 10 and 27 ( 7) and primary insulation panels 24. In this way, the secondary insulating panel 107 includes a base plate 109 , a secondary insulating polymer foam layer 156 and a cover plate 111 . In the same manner, the primary insulating panel 124 includes a base plate 125 , a primary insulating polymer foam layer 157 and a cover plate 129 . Furthermore, the base plate 109 extends beyond the secondary insulating polymer foam layer 156 and the cover plate 111 at the sides of the secondary insulating panel 107 .

In this second embodiment, the fixing device 8 consists of two separate parts, namely a first part forming a secondary retaining member 158 cooperating with the secondary insulating panels 107, and a first part forming the secondary insulating panels 107. 124 and cooperating with the second part forming the primary retaining member 159. As a result of the offset of the corner regions of the primary insulating panels 124 relative to the corner region of the secondary insulating panels 107 , the secondary retaining members 158 are separated from and offset from the primary retaining members 159 .

The secondary retaining member 158 can be manufactured in different ways. For example, the secondary retaining member 158 may include a screwed pin that is secured to the carrier structure, and the secondary support plate is mounted on the pin and held on the pin by a nut. Then, the secondary supporting plate is supported either directly on the base plate 109 of the secondary insulating panel 107 or via a wedge placed on the protruding part of the base plate 109 . In order to ensure the continuity of insulation, an insulation stopper may be inserted into the vent formed by the recesses of adjacent secondary insulation panels 107 . In the same way, to ensure the continuity of the bearing surface formed by the cover plate 111, a closing plate of, for example, plywood is to be received in the counterbore of the cover plate 111 of the adjacent secondary insulation panels 107. can

In a manufacturing variant not shown, the secondary thermal insulation panels 107 are identical to the secondary thermal insulation panels 7 described above. In this variant, the secondary retaining member 158 may have a structure similar to that described above for the fixing device 8 in which all elements disposed above the force dissipation plate 21 are removed. In this example, the force dissipation plate 21 and the countbore to receive it may be eliminated.

There may be various numbers of secondary retaining members 158 per secondary insulating panel 107, eg ranging from 2 to 5, eg at the corners of the secondary insulating panels 107 and/or Alternatively, it may be disposed in the first direction or the second direction within the gap between the two secondary insulation panels 107 . Other embodiments of secondary retaining members are described in WO-A-2013093262.

In FIG. 14 , the primary retaining member 159 comprises an anchoring plate 160 , for example with a square or circular contour, which covers the secondary insulating polymer foam layer 156 . It is fixed, for example by adhesive bonding, within a counterbore provided in the surface of the plate 111 . The fixing plate 160 has a tapped hole opened in the upper surface of the cover plate 111, that is, in the surface of the cover plate 11 facing the inside of the tank. A pin 145, identical to pin 45 described above, is screwed into the tapped hole of the plate 160.

Primary retaining member 159 also has similar features to those described above with reference to FIGS. In this way, the primary holding member 159 includes a primary holding plate held on the pin 145 by a nut and, optionally, a resilient washer. This primary retaining member 159 connects, on the one hand, the fixing device 8 and, on the other hand, between the base plate 25 and the wedge 32, in a manner similar to that described above, the base plate 125 and Collaborate with Wedge. In other words, on the one hand, the primary holding member 159 and, on the other hand, the base plate 25 and the wedge, under the influence of the temperature change in the tank, the primary holding member 159 of the primary holding member 159 on the wedge. To retain support, it is given a size with a selected heat shrink coefficient.

Referring to Fig. 12, a cutaway view of a LNG carrier shows a sealed and insulated tank 71 which is generally prismatic and mounted within the double hull of the carrier. The tank wall 71 comprises a primary sealing barrier intended to come into contact with the liquefied natural gas contained in the tank, a secondary sealing barrier disposed between the primary sealing barrier and the double hull 72 of the carrier, and the primary sealing barrier. and two thermal insulation barriers respectively disposed between the secondary sealing barrier and between the secondary sealing barrier and the double hull (72).

In a manner known per se, in order to transfer the LNG cargo to or from the tank 71, the loading/unloading pipes 73 arranged on the upper bridge of the carrier are connected using suitable connectors. It can be connected to a marine or port terminal.

12 shows an example of a marine terminal comprising a loading and unloading station 75 , an underwater pipeline 76 and an onshore installation 77 . The loading and unloading station 75 is a fixed offshore installation comprising a movable arm 74 and a tower 78 supporting the movable arm 74 . The movable arm 74 supports a bundle of flexible insulated pipes 79 which can be connected to the loading/unloading pipes 73. The orientable movable arm 74 is suitable for transport vessels of all sizes. A connecting pipe, not shown, extends inside the tower 78. The loading and unloading station 75 enables loading and unloading of the LNG carrier 70 to or from the shore facility 77 . The facility includes liquefied gas storage tanks 80 and connecting pipes 81 which are connected to a loading or unloading station 75 via submersible pipes 76. The submersible piping 76 enables the transfer of liquefied gas between the loading or unloading station 75 and the onshore facility 77 over long distances, for example 5 Km, which during loading and unloading operations the liquefied natural gas carrier ( 70) to be kept at a great distance from the shore.

To generate the pressure required for the transfer of liquefied gas, pumps aboard the transport vessel 70 and/or pumps installed on shore installations 77 and/or pumps installed at the loading and unloading station 75 are used. do.

Although the present invention has been described in connection with several specific embodiments, the present invention is not limited to those embodiments, but includes all technical equivalents and combinations of the described means provided that they fall within the scope of the present invention. It is clear that doing

Use of the verbs "have", "comprise", "have" and their conjugations does not exclude the presence of elements or steps other than those recited in a claim.

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

Claims (17)

A sealed and thermally insulating tank for storing a fluid comprising a tank wall (1, 101), comprising:
The tank wall (1, 101) comprises a thermally insulating barrier intended to be fixed to a carrier structure (3, 103), from the outside to the inside of the tank, in the thickness direction of the tank wall and having a sealing membrane (6, 106) continuously supported against the insulating barrier (5, 105);
The thermal insulation barrier (5, 105) comprises parallelepiped thermal insulation panels (24, 124) placed side by side and intended to be fixed to the carrier structure (3, 103), said thermal insulation panels (24, 124) ) has base plates 25, 125 and insulating packings 26, 28, 157, and the base plates 25, 125 protrude laterally from the insulating packings 26, 28, 157. forming a support surface 31, the support surface 31 facing the inside of the tank, a wedge 32 is disposed on the support surface 31, the wedge 32 is having an inner surface facing the inside of the tank;
Anchoring devices intended to be anchored to the carrier structure 3, 103 between the insulating panels 24, 124 cooperate with the insulating panels 24, 124, which anchoring devices It is intended to hold the insulating panels (24, 124) against the carrier structure (3, 103);
At least one of the fixing devices (45, 145, 159) includes a support member (33) having an outer surface facing the wedge (32), the support member (33) having an outer surface facing the support surface ( 31) is configured to be supported on the inner surface of the wedge 32,
One of the wedge 32 and the base plate 25 has a thermal contraction coefficient in the thickness direction greater than the thermal contraction coefficient of the holding device 45, 145, 159 in the thickness direction of the tank wall. wherein the other one of the wedge 32 and the base plate 25 has a heat shrinkage coefficient in the thickness direction smaller than that of the holding device 45, 145, 159 in the thickness direction. . According to claim 1,
The heat shrinkage coefficient of the wedge (32) is smaller than that of the base plate (25, 125). According to claim 1 or 2,
The wedge 32 and the base plate 25 , 125 have the support member 33 on the inner surface of the wedge 32 in the direction of the support surface 31 when the temperature decreases from ambient temperature. A sealed and insulated tank having individual dimensions in the thickness direction, to be supported. According to claim 1 or 2,
In the case of a temperature change from 20°C to -163°C, the dimensional change of the fixing device 45, 145, 159 in the thickness direction of the tank wall results in the base plate 25, 125 and the wedge 32. A sealed and insulated tank, greater than the dimensional change in the thickness direction of the formed assembly. According to claim 1 or 2,
Between the fixing device 45, 145, 159 and the assembly formed of the base plate 25, 125 and the wedge 32, during a temperature change from 20 ° C to -163 ° C in the thickness direction of the tank wall A sealed and insulated tank, wherein the difference in size change is between 5.50E-05 mm and 9.69E-02 mm. According to claim 1 or 2,
the wedge (32) is made of plywood and is configured to have fibers oriented in a plane parallel to the thickness direction of the tank wall;
wherein the base plate (25, 125) is made of plywood and is configured to have fibers oriented in a plane perpendicular to the thickness direction of the tank wall. According to claim 1 or 2,
wherein the wedge (32) has a coefficient of heat shrinkage between 4E-06K ^-1 and 8E-06K ^-1 in the thickness direction of the tank wall. According to claim 1 or 2,
wherein the base plate (25, 125) has a heat shrinkage coefficient between 3E-05K ^-1 and 4E-05K ^-1 in the thickness direction of the tank wall. According to claim 1 or 2,
wherein the holding device (45, 145, 145) has a heat shrinkage coefficient between 1.4E-05K ^-1 and 1.8E-05K ^-1 in the thickness direction of the tank wall. According to claim 1 or 2,
In the thickness direction of the tank wall, the base plate (25, 125) has a thickness of 9 mm, and the wedge has a thickness between 17.6 mm and 68 mm. According to claim 1 or 2,
wherein the wedge lies on at least 50% of the supporting surface (31) of the insulating panel (24, 124). According to claim 1 or 2,
The wedge 32 is arranged so that the support member 33 is supported on the wedge 32 in the direction of the supporting surfaces 31 of the two adjacent insulating panels 24 , 124 . Sealed and insulated tank, disposed on the support surface (31) of (24, 124). According to claim 1 or 2,
The insulating barrier is a primary insulating barrier, the insulating panels are primary insulating panels, the sealing membrane is a primary sealing membrane, the supporting member 33 is a primary supporting member, and the tank wall is the primary insulating barrier and the carrier. A sealed and insulated tank further comprising a secondary thermal insulation barrier and a secondary sealing membrane intended to be interposed between the structures. According to claim 1 or 2,
At least one of the insulation panels includes a cover plate, the insulation packing is interposed between the base plate and the cover plate, and the insulation panel further includes an intermediate plate disposed between the base plate and the cover plate. and the insulating packing includes a first insulating polymer foam layer sandwiched between the base plate and the middle plate and a second insulating polymer foam layer sandwiched between the middle plate and the cover plate,
Recesses are provided in the insulating polymer foam layers and the mid plate and cover plate, and the base plate protrudes with respect to the insulating polymer foam layers and the mid plate and base plate to provide support on the base plate. A sealed and insulated tank, providing a surface. As a tanker 70 for transporting fluid,
The transport vessel comprises a double hull (72) and a tank (71) according to claim 1 or 2 disposed within the double hull (72). A method for loading and unloading a transport vessel (70) according to claim 15,
Fluid is passed from the floating or onshore storage facility 77 to or from the tank 71 of the transporter to the floating or onshore storage facility 77 via insulated pipes 73, 79, 76, 81. transferred to, how. As a transfer system for fluid,
The system comprises a transport ship (70) according to claim 15, insulated pipes (73, 79, 76, 81) arranged to connect a tank (71) installed in the hull of the transport ship to a floating or onshore storage facility (77), and a pump for propelling fluid through the insulated piping from a floating or land storage facility to a tank of the transport vessel or from a tank of the transport vessel to a floating or land storage facility.

Images