KR102399177B1 - sealed and insulated tanks - Google Patents

Abstract

The sealing and insulating tank includes a secondary insulating barrier (1), a secondary sealing membrane (2), a primary insulating barrier (3) and a primary sealing membrane (4), and a plurality of primary fixing members (12) interacts with at least one primary thermal insulation panel 11 of the primary thermal insulation barrier 3 , and the primary fixing member 12 passes through the base 30 and the opening of the secondary sealing membrane 2 . A stem (31), bearing elements (16, 54) mounted on the stem (31) and supporting the primary insulating panel (11), coupled to the stem (31) and sealed to the secondary sealing membrane (2) A seal washer 34 comprising a collar 37 secured to ) is included.

Description

sealed and insulated tanks

The present invention relates to the field of sealed and thermally insulating tanks with membranes. In particular, the present invention relates to the field of sealed and insulated tanks for the storage and/or transport of liquefied gases at low temperatures, for example liquefied natural gas, also known as LPG (Liquefied Petroleum Gas), for example at -50 °C. It relates to tanks for the transport of liquefied natural gas (LNG) between 0 °C or about -162 °C at atmospheric pressure. These tanks can be installed onshore or on a floating structure. In the case of a floating structure, the tank may be for transporting the liquefied gas or for receiving the liquefied gas serving as fuel for the propulsion of the floating structure.

In one embodiment, the liquefied gas is LNG, ie a mixture with a high methane content stored at a temperature of about -162°C at atmospheric pressure. Other liquefied gases are also contemplated, in particular ethane, propane, butane or ethylene. The liquefied gas can also be stored, for example, under a relative pressure of 2 to 20 bar, in particular a relative pressure close to 2 bar.

WO2014096600 discloses a closed insulated tank for storage of liquefied natural gas, which is arranged as a supporting structure and has a multi-layered wall from the outside to the inside of the tank, which is a secondary insulating barrier fixed to the supporting structure, a secondary insulating barrier a secondary sealing membrane supported by the secondary sealing membrane, a primary insulating barrier overlying the secondary sealing membrane, and a primary sealing membrane supported by the primary insulating barrier and intended for contact with the liquefied natural gas stored in the tank.

Each of the primary and secondary insulating barriers comprises a set of primary and secondary insulating panels, generally parallelepiped in shape, disposed in parallel to form a support surface for each sealed membrane. The insulating panel is fixed to the supporting structure and fixed to the supporting structure through fixing devices located at the corners of the primary and secondary insulating panels. Each fixing device thus interacts with the edges of four adjacent secondary insulating panels and the edges of four adjacent primary insulating panels to hold them relative to the supporting structure.

WO2013104850 describes a sealed and insulating tank comprising a multilayer structure in which the edges of the insulating panels of the primary insulating barrier are not aligned with the edges of the insulating panels of the secondary insulating barrier. In such tanks, the primary anchoring device, which interacts with the primary insulation panel, is fixed to a plate fixed to the secondary insulation panel. Accordingly, the primary fixing device and the primary insulating panel are fixed to the supporting structure by the secondary insulating panel.

In all cases the secondary insulation panel is susceptible to deformation and/or movement. Specifically, the secondary insulation panel has thermal gradients, which can be bent due to differential contraction phenomena. Moreover, deformation of the supporting structure causes deformation and/or movement of the secondary insulation panel. This is particularly the case when the supporting structure consists of the inner hull of the floating structure. Moreover, where these hulls form ballast compartments, movement of the ballast liquid in the ballast compartments also causes significant deformation of the supporting structure and thus the deformation and/or movement of secondary insulation panels secured to the supporting structure. can cause

Moreover, the movement of liquid contained in the tank can cause stress on the primary sealing membrane, especially if the membrane contains protruding parts such as corrugations. These stresses are transferred to the primary insulating panel to which the primary sealing membrane is fixed and tend to move the primary insulating panel laterally. This causes the stress to be concentrated in the primary fixture.

However, to ensure sealing of the secondary sealing membrane, the primary securing device comprises a collar hermetically welded to the secondary sealing membrane. This collar is secured to a stud carrying the corresponding primary insulating panel or bearing member which interacts with the panel. Upon deformation and/or movement of the secondary insulation panel and/or movement of the primary insulation panel, this connection between the primary fixing device and the secondary sealing membrane is to create a concentration of stress in the weld between the collar and the secondary sealing membrane. easy, which can damage the weld and the secondary sealing membrane.

In particular, in the case of the primary fixing device fixed to the secondary insulating panel, the primary fixing device is moved due to deformation and/or movement of the secondary insulating panel. This movement of the primary fixation device is transmitted to the collar rigidly secured to the stud, which stresses the sealed connection between the collar and the secondary sealing membrane. Such stresses may damage the secondary sealing membrane and/or the sealed connection between the collar and the secondary sealing membrane, thereby compromising the seal of the secondary sealing membrane.

The idea forming the basis of the present invention is to limit the stress concentration at the connection between the secondary sealing membrane and the primary fixing member of the primary insulating panel. The idea forming the basis of the present invention is to make a flexible sealed connection between the primary fixing member and the secondary sealing membrane. Accordingly, the idea forming the basis of the present invention is to allow relative movement between the secondary sealing membrane and the primary fixing member. The idea forming the basis of the present invention relates to whether the primary fastening member is fixed directly to the supporting structure, for example by being produced jointly with the secondary fastening member, or indirectly, for example by fastening to a secondary insulating panel. to allow these movements without Accordingly, another idea forming the basis of the present invention is to allow relative movement between the secondary sealing membrane and the secondary insulating panel to which the primary fastening member is fixed.

According to one embodiment, the present invention provides a sealed and insulated tank comprising a tank wall, wherein the tank wall is continuous from the outside of the tank to the inside of the tank in the thickness direction of the tank wall, the secondary fixed to the support wall an insulating barrier, a secondary sealing membrane overlying the secondary insulating barrier, a primary insulating barrier overlying the secondary sealing membrane, and a primary sealing membrane-1 overlying the primary insulating barrier and in contact with the product contained within the tank the car sealing membrane comprising a plurality of primary insulating panels disposed side by side;

The tank further comprises a plurality of primary securing members adapted to be held directly or indirectly to the support wall, each of the primary securing members in such a way as to retain at least one primary insulating panel to the secondary sealing membrane, interact with at least one primary thermal insulation panel of the plurality of primary thermal insulation panels;

one or more or each of the primary fixation members,

- a base intended to be held directly or indirectly on the supporting wall;

- a stem extending from the base in the thickness direction of the tank wall towards the primary sealing membrane and passing through the opening of the secondary sealing membrane,

- bearing elements mounted on the stem, supporting the primary insulation panel in such a way as to hold the primary insulation panel on the secondary sealing membrane;

- a sealing washer coupled to the stem between the bearing element and the opening in the secondary sealing membrane - the sealing washer having a central opening through which the stem passes, the sealing washer sealing to the secondary sealing membrane around the opening in the secondary sealing membrane fixed as-,

-contains a deformable seal sealingly connecting the sealing washer and the stem in a manner that permits relative movement between the sealing washer and the stem;

These features allow relative movement between the secondary sealing membrane and the primary fixing member without risk of damage to the secondary sealing membrane or the sealed connection between the primary fixing member and the secondary sealing membrane. In particular, the deformable seal creates a flexible sealed connection between the stem of the primary fastening element on the one hand and the sealing washer on the other hand, thereby ensuring sealing of the secondary sealing membrane. This primary fixing member thus permits relative movement between the secondary and/or primary insulating panel and the secondary sealing membrane without risk of damage to the secondary sealing membrane or the connection between the primary fixing member and the secondary sealing membrane. do.

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

The primary fastening members described above may be used over the entire tank wall or only in a localized portion of the tank wall, such as a ballast area. According to one embodiment, the tank wall has a vertical component defining the height of said tank wall in the direction of gravity, the tank wall comprising a base, a stem, a bearing element, a sealing element and a deformable seal, respectively, as described and a plurality of primary securing members, wherein the plurality of primary securing members are disposed below the tank wall, for example at least two-thirds of the tank wall height.

According to an embodiment, the tank wall is a first tank wall, the tank further comprising a second tank wall, the first tank wall and the second tank wall forming an edge of the tank, the first tank wall being a plurality of primary fixing members each comprising a base, a stem, a bearing element, a sealing washer and a deformable seal, wherein the primary fixing members are arranged to be spaced apart from the edge of the tank by a predetermined threshold or less. For example, the preset threshold corresponds to a width of five thermal insulation panels, and the plurality of primary fixing members are arranged to hold five consecutive primary thermal insulation panels in a direction perpendicular to the edge, for example.

The part of the tank wall located at the bottom of the tank is subject to particularly high stresses, for example because of the ballast of the carrier in the case of a transverse tank wall fixed to the cofferdam wall, or, for example, because of the weight of the liquid being transported. receive Likewise, the edge region of the tank is also subjected to particularly high stresses, including the pressure generated by the water in the ballast of the carrier. These stresses tend to cause relative movement between the primary insulating barrier and/or the secondary insulating barrier on the one hand and between the secondary sealing membranes at the tank bottom part and/or the edge of the tank on the other hand. Thus, by the arrangement of the primary fixing member, the risk of damage to the secondary sealing membrane is limited by virtue of the flexibility of the connection between the primary fixing member and the secondary sealing membrane.

Primary insulation panels can be produced in a variety of ways. According to an embodiment, the primary insulation panel has a parallelepiped shape.

According to an embodiment, the primary insulating panel includes a bottom plate, a cover plate, and an insulating lining inserted between the bottom plate and the cover plate.

The bearing element may bear various portions of the primary thermal insulation panel. According to one embodiment, the bearing element bears directly on said primary insulating panel, for example bearing on the bottom plate of the primary panel. According to an embodiment, the bearing element is supported indirectly on the primary thermal insulation panel, for example via a wedge inserted between the bearing element and the element of the primary thermal insulation panel, eg the bottom plate of the primary thermal insulation panel.

According to one embodiment, the edge of the primary insulating panel comprises a recess, said recess exposing a bearing surface facing the interior of the tank. According to an embodiment, the bearing element of the primary fixing member directly or indirectly supports the bearing surface of the primary thermal insulation panel. According to one embodiment, the recess is formed in the cover plate and in the insulating lining. According to one embodiment, the bearing surface is formed by a portion of the bottom plate protruding from a recess formed in the insulating lining and the cover plate. According to one embodiment, the bearing surface is formed by a wedge arranged between the bearing element and a part of the bottom plate projecting from a recess formed in the insulating lining and the cover plate.

According to one embodiment, the primary fastening member interacts with the edges of the adjacent primary insulating panel, eg the adjacent four panel edges, in such a way as to secure the primary panel to the support wall.

The sealing washer can be secured to the secondary sealing membrane in a variety of ways. According to one embodiment, the sealing washer or collar is sealingly welded to the secondary sealing membrane.

According to an embodiment, the deformable seal is deformable in the thickness direction of the tank wall in such a way that the sealing washer slides along the stem in a direction perpendicular to the thickness direction of the tank wall.

According to one embodiment, the central opening of the sealing washer has a lateral dimension greater than the lateral dimension of a portion of the stem coupled to the central opening in such a way that the stem is movable in the central opening of the seal. Washers perpendicular to the thickness direction of the tank wall. This sealing washer allows free movement of the sealing washer relative to the stem in a direction perpendicular to the thickness direction of the tank wall. In particular, this primary fastening member permits movement of the sealed connection between the sealing washer and the secondary sealing membrane relative to a bearing element mounted on the stem and cooperating with the primary insulating panel or panels. Therefore, no movement of the secondary and/or primary insulating panel in the plane perpendicular to the thickness direction of the tank wall is transmitted by the primary fixing member to the secondary sealing membrane, and thus differential contraction, support Reduces the stresses associated with wall deformation or liquid movement in the tank and limits the risk of damage to the secondary sealing membrane or the sealed connection between the sealing washer and the secondary sealing membrane.

According to an embodiment, the primary fastening member further comprises a stop supported by the stem, the stop being arranged on the stem between the bearing element and the sealing washer, the stop being primary with respect to the stem in the thickness direction of the tank wall. It has a stop surface to stop movement of the sealing washer towards the sealing membrane.

Due to this feature, deformation of the secondary sealing membrane in the thickness direction of the tank wall is limited from the sealed connection between the sealing washer and the opening of the secondary sealing membrane. In particular, when overpressure occurs in the secondary thermal insulation barrier or the secondary thermal insulation barrier is deformed, the secondary sealing membrane is prevented from being deformed in the thickness direction of the tank wall. Specifically, since the sealing washer is hermetically fixed to the secondary sealing membrane around the opening of the secondary sealing membrane, when the secondary sealing membrane tends to move into the tank, at the sealed connection with the sealing washer Local deformation of the secondary sealing membrane is blocked by a sealing washer coming adjacent against the stop surface. Thus, the risk of damage to the secondary sealing membrane, for example by perforation, is reduced. Moreover, this limitation of local deformation of the secondary sealing membrane makes it possible to limit the risk of damage to the deformable seal.

According to one embodiment, the stem has a shoulder, said shoulder laterally from the stem, ie in a direction perpendicular to the longitudinal direction of the stem, beyond the central opening of the sealing washer, the outer surface of the shoulder forming a stopping surface do. Such a stop can simply be created without additional parts.

According to an embodiment, the primary fixing member further comprises a bell mounted to the stem, the bell comprising a mounting portion and a protection portion, the mounting portion having a central passageway through which the stem passes, the protection portion including the mounting portion from towards the collar of the sealing washer, extending in the thickness direction of the tank wall, the protective portion being hollow, and the deformable sealing portion being partially or entirely accommodated in the protective portion. These bells surrounding the stem of the primary anchoring member provide protection for the stem and the deformable seal.

According to one embodiment, the mounting portion of the bell comprises a plateau extending in a plane perpendicular to the thickness direction of the tank wall, the plateau comprising a passageway through the bell.

According to an embodiment, the deformable seal is completely received in the protective part of the bell. The deformable seal is thus protected, for example, by a bell during mounting of the primary fastening element to the tank. According to one embodiment, the deformable seal is secured to the stem between the passage of the mounting part of the bell and the seal washer.

According to one embodiment, the end of the protective part opposite the mounting part of the bell comprises a radially outwardly extending lip, the outer surface of which is to stop the movement of the sealing washer in the thickness direction of the tank wall. to form a stop surface for

According to an embodiment, the outer end of the protective part opposite the mounting part forms a stopping surface facing the sealing washer for stopping the movement of the sealing washer in the thickness direction of the tank wall.

According to one embodiment, the bell is fixed to the stem. Thus, by means of the protective part having a fixed position relative to the stem, a stop surface can be formed which blocks the movement of the sealing washer relative to the stem. According to one embodiment, the mounting part of the bell is welded to the stem.

According to one embodiment, the deformable seal comprises a deformable bellows, wherein the deformable bellows is hollow and extends axially along a stem, wherein a first axial end of the bellows is sealingly fixed to the stem; The second axial end of the bellows is sealingly secured to the sealing washer.

This deformable seal in the form of a bellows is simple to produce and allows sufficient sealed deformation of the deformable seal. These bellows can be made of various materials. According to one embodiment, the bellows is made of stainless steel. These stainless steel bellows are thin enough to allow elastic deformation. In one embodiment, the bellows is made of stainless steel with a thickness of between 0.1 mm and 0.5 mm, for example between 0.1 mm and 0.3 mm.

According to an embodiment, the bellows has a plurality of folds of the same or increasing diameter, and a central portion of the bellows formed by the plurality of folds has a substantially rotational cylinder shape.

According to one embodiment, the bellows has at least 3 folds or folds, preferably 3 to 32 folds, ideally 6 to 24 folds.

According to one embodiment, the bellows has a flared shape, wherein a second axial end of the bellows is secured to a sealing washer having a circumferential dimension greater than a circumferential dimension of a first axial end of the bellows fixed to the stem.

According to one embodiment, the bellows has a plurality of folds having a diameter increasing from an end secured to the stem toward an end secured to the sealing washer. Accordingly, the portion of the bellows formed by this plurality of folds has a conical shape, and the portion of its largest dimension is located at the end fixed to the sealing washer.

According to one embodiment, the sealing washer has an inner surface extending in a plane perpendicular to the thickness direction of the tank wall. According to an embodiment, in order to block movement of the sealing washer relative to the stem in the thickness direction of the tank, the inner surface is arranged to face the stop surface in such a way that it interacts with the stop surface, for example a bell or a part of the stem do.

According to an embodiment, the deformable seal is secured to an inner surface of the seal washer, for example a radially outer part of the inner surface of the seal washer.

According to one embodiment, the sealing washer comprises a rib projecting from an inner surface of the sealing washer, the deformable sealing portion being sealingly secured to said rib. According to one embodiment, the ribs of the sealing washer extend from a radially inner part of the inner surface of the sealing washer.

According to one embodiment, the tank comprises a plurality of secondary fastening members, each secondary fastening member being fixed to the support wall and forming a secondary thermal insulation barrier when the secondary fastening member is fixed to the support wall. to interact with the secondary insulating barrier in such a way that it bears in the direction of

According to one embodiment, the base of the primary fixing member is fixed to the secondary fixing member.

According to one embodiment, the base of the primary fixing member is firmly fixed to the secondary insulating barrier. In this case, the primary fastening member is held on the supporting wall via a secondary insulating barrier.

According to an embodiment, the secondary thermal insulation barrier includes a plurality of secondary thermal insulation panels arranged side by side. According to an embodiment, the one or more or each secondary insulating panel comprises a bottom plate, a cover plate and an insulating lining interposed between the bottom plate and the cover plate, wherein the secondary sealing membrane comprises a cover plate opposite to the insulating lining. placed on the inner surface. According to an embodiment, the one or more or each secondary thermal insulation panel comprises an intermediate plate interposed between a bottom plate and a cover plate of the secondary thermal insulation panel, wherein the thermal insulation lining of the secondary thermal insulation panel comprises a floor and an external thermal insulation lining inserted between the plate and the intermediate plate, and an internal thermal insulation lining inserted between the intermediate plate and the cover plate.

According to an embodiment, the secondary thermal insulation barrier comprises an anchoring plate, and the base of the primary anchoring member is fixed to the anchoring plate. According to one embodiment, the fixing plate is received in a recess made in the cover plate of the secondary heat insulation panel, the fixing plate has an inner surface flush with the inner surface of the cover plate.

According to one embodiment, the fixing plate includes a threaded opening, the base has an externally threaded end, and by screwing the threaded end of the base to the threaded opening of the fixing plate, the base of the primary fixing member comprises: fixed to the fixing plate.

According to one embodiment, the inner end of the stem opposite the base is threaded, the primary fixing member further comprising a nut screwed into the threaded inner end, the bearing element comprising the nut and the base of the primary fixing member. inserted between

According to an embodiment, the deformable seal is inserted between the bearing element and the seal washer.

According to an embodiment, one or more resilient washers are inserted between the nut and the bearing element.

According to one embodiment, the primary fixing member has a fixing shoulder projecting laterally from the stem, said fixing shoulder defining a fixing surface extending in a plane perpendicular to the thickness direction, the fixing surface facing the bearing element and , the deformable seal is fixed sealingly to the fixed surface.

According to one embodiment, the inner end of the deformable seal fixed to the stem is inserted between the mounting part of the bell and the flat fastening surface of the fixed shoulder.

According to an embodiment, the bell moves freely in the thickness direction of the tank wall. According to one embodiment, the freedom of movement of the bell is limited on the one hand by a nut or elastic washer or applicable washers mounted on the stem and on the other hand by the fixing surface of the fixing shoulder.

According to one embodiment, the inner axial end of the deformable seal secured to the stem is inserted between the anchoring surface of the anchoring shoulder and a nut mounted on the stem or between an applicable resilient washer.

According to one embodiment, the secondary sealing membrane and/or the primary sealing membrane is an alloy of iron and nickel, for example, the coefficient of expansion is generally 1.2 x 10-6 and 2 x 10-6 K- It is made of an alloy that is between 1. According to one embodiment, the secondary sealing membrane and/or the primary sealing membrane are made of, for example, an alloy of iron and manganese, which generally has a coefficient of expansion of about 7 to 9 Х 10-6 K-1. According to one embodiment, the secondary sealing membrane and/or the primary sealing membrane comprises a plurality of strakes having raised edges, arranged side by side and welded in pairs through their raised edges.

According to an embodiment, the primary sealing membrane and/or the secondary sealing membrane comprises a plurality of preferably rectangular metal plates welded to each other. According to an embodiment, the primary sealing membrane and/or the secondary sealing membrane comprises a first series of parallel corrugations extending in a first direction and a second series of parallel corrugations extending in a second direction. a second series of parallel corrugations, wherein the first direction and the second direction are fixed.

According to one embodiment, a transfer wedge is disposed around the bell in a gap between the bell and an adjacent primary insulation panel, for example in the gap between the bell and the bottom plate of an adjacent primary insulation panel. . Thanks to this feature, the lateral movement of the insulating panel interacting with the fixing member is transmitted via the transfer wedge to the bell, stem and stem support (e.g. secondary insulating barrier), thereby providing a seal between the sealing washer and the sealing membrane. The transverse forces exerted by the primary insulation panel can be tolerated without the risk of damage to the connections.

According to one embodiment, in the thickness direction of the tank wall, the conveying wedge has a thickness smaller than the thickness of the bottom plate of the primary insulation panel. Therefore, when the primary insulation panel moves laterally, only the bottom plate abuts against the transfer wedge, so that the force between the primary insulation panel and the transfer wedge is well transmitted.

According to an embodiment, the conveying wedge comprises an outer portion and a plateau, the outer portion extending around the sealing washer in the thickness direction of the tank wall, the flat portion surrounding the bell, the outer portion and the flat portion, the sealing washer includes a central opening defining a housing received in the gap, through which the wedge can transmit a lateral force to the bell without interfering with the sealing washer.

According to one embodiment, the conveying wedge further comprises an inner portion extending from the flat portion and surrounding the bell.

According to one embodiment, the outer part of the conveying wedge has a circular cylindrical shape. According to one embodiment, the outer part is coaxial with the stem.

According to an embodiment, the transport wedge comprises a wing, preferably a plurality of wing parts, extending radially from the outer part of the transport wedge and parallel to the thickness direction of the tank wall. According to one embodiment, the wing or wing parts are accommodated between two adjacent primary insulating panels.

According to one embodiment, the transport wedge is smaller than the space available between the panels. This facilitates the mounting of wedges between panels.

According to an embodiment, the sealing washer comprises a flat part and the bell comprises a flat part, wherein the flat parts are a seal deformable when the fastening member is screwed into its support part, for example with a secondary insulating barrier. The part may be configured to be gripped by the screwing tool so that the stem and the sealing washer can rotate together without twisting. According to one embodiment, the sealing washer comprises a flat part and the stem comprises a flat part, wherein the flat part is to be gripped by a screwing tool such that the deformable seal is not twisted and the stem and the seal washer rotate together. can

Such tanks may form part of, for example, an onshore storage facility for storage of LNG, or may be used in floating structures, onshore or in the deep sea, in particular LNG carriers, floating storage and regasification units (FSRUs), remote floating It can be installed in a remote floating production and storage unit (FPSO), etc. These tanks can also be used as fuel tanks in all types of carriers.

According to one embodiment, the present invention also provides a carrier for the transport of cold liquid products comprising a double hull and a tank as described above arranged in the double hull.

According to an embodiment, the present invention also provides a method of loading or unloading such a carrier, wherein the cold liquid product is transported via insulated pipelines to a floating or onshore storage facility or from the carrier. can be transported to tanks.

According to one embodiment, the present invention also provides a conveying system for conveying cold liquid products, said system comprising an insulated pipe arranged to connect said carrier, a tank installed in the hull of said carrier, to a floating or onshore storage facility. lines, including a pump for pumping a flow of cold liquid product through insulated pipelines to a floating or onshore storage facility or to a tank of the carrier.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood with reference to the accompanying non-limiting drawings, and other objects, details, features and advantages of the present invention will also become apparent from the description of several specific embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partial plan view with a primary sealing membrane cut away from a portion of a sealing and insulating tank wall, not shown.
FIG. 2 is a cross-sectional view of the tank wall of FIG. 1 taken along section AA shown in FIG. 1 ;
FIG. 3 is a detailed view of area B of FIG. 2 showing a primary fixing member securing two adjacent primary insulating panels; FIG.
FIG. 4 is a schematic perspective view of the fixing member of FIG. 3 ;
5 is a schematic perspective view of the primary fixing member shown in FIG. 4 in which the bell is not shown.
6 is a cross-sectional view of a second embodiment of the primary fixing member.
7 is a cross-sectional view of a third embodiment of the primary fixing member.
8 is a cross-sectional view of a primary fixing member according to a fourth embodiment.
9 illustrates a partially deployed state of a tank of an LNG carrier and a terminal for loading and unloading the tank.
10 is a schematic perspective view of a primary fixing member according to a fifth embodiment.
FIG. 11 is a cross-sectional view of the primary anchoring member of FIG. 10 cooperating with two primary insulating panels; FIG.
Fig. 12 is a schematic perspective view of the fixing member of Fig. 11;
13 is a cross-sectional view of a primary fixing member according to a sixth embodiment, wherein the primary fixing member includes a transfer wedge.
14 is a view from above of the primary fixing member of FIG. 13 .
15 is a schematic perspective view with a cross-section along a portion of a secondary insulating barrier upon which a portion of the secondary sealing membrane rests, the secondary insulating barrier comprising a fastening member for receiving the primary fixation;
Fig. 16 is a perspective view of a portion of the primary securing member and a tool of the securing member for mounting said portion of the primary securing member onto the securing plate of the secondary thermal insulation barrier of Fig. 15;
FIG. 17 is a perspective view of a cross-section passing through the primary fixing member of FIG. 16 to which a bell is added and mounted on the fixing plate of the secondary thermal insulation barrier.

In the remainder of the description, the terms "external" and "internal" are used to designate the relative position of an element with respect to another element with reference to the interior of the tank according to the definitions provided in the description. Thus, elements close to or facing the interior of the tank are described as interior elements as opposed to external elements that are close to or facing the exterior of the tank. Likewise, the expressions "radially at the periphery" or "radially outer" define a circular element as opposed to "radially inner", which refers to the portion close to the axis. It refers to the part that is far from the axis. Also, the expression “transverse” is used to describe the direction of movement or expansion of an element in a plane perpendicular to the thickness direction of the tank wall.

A sealed and thermally insulating tank for storing a liquefied fluid such as liquefied natural gas (LNG) includes a plurality of tank walls having a multilayer structure. 1 and 2 show a wall part of a closed and insulated tank. 1 and 2, the wall of the tank is continuous through the thickness from the outside to the inside of the tank, and a secondary insulating barrier (1), a secondary insulating barrier (1) maintained on a supporting wall (not shown) ) facing the secondary sealing membrane (2), the primary insulating barrier facing the secondary sealing membrane (2), and the liquefied natural gas contained in the tank. and a primary sealed membrane (4). The support structure may in particular be formed by a hull or a double hull of a carrier. The support structure comprises a plurality of support walls defining the general shape of the tank, which is generally polyhedral, each tank wall being fixed to a respective support wall.

The secondary insulating barrier 1 includes a plurality of secondary insulating panels 5 fixed to the supporting wall by secondary anchoring members (not shown). The secondary insulating panels 5 are generally parallelepiped in shape and arranged in parallel rows. Beads of mastic (not shown) are placed between the secondary insulating panel 5 and the supporting wall to fill the gap between the supporting wall and a flat reference surface. Kraft paper can be inserted between the mastic bead and the supporting wall to prevent the mastic bead from sticking to the supporting wall. Alternatively, beads of mastic are in direct contact with the supporting wall to secure the secondary insulating panel 5 by adhesion to the supporting wall.

The structure of the secondary heat insulation panel 5 shown in FIG. 2 has a bottom plate 7 , a cover plate 8 , and a heat insulation lining inserted between the bottom plate 7 and the cover plate 8 . (9, insulating lining). The bottom plate 7 and the cover plate 8 are made, for example, of plywood. The insulating lining 9 consists, for example, of a layer of insulating polymer foam sandwiched between the bottom plate 7 and the cover plate 8 . The insulating lining (9) is glued to the bottom plate (7) and the cover plate (8). The insulating polymer foam may in particular be a polyurethane-based foam (optionally reinforced with fibers).

The secondary insulating panel 5 includes recesses for receiving secondary fixing members. Such a recess is made, for example, in the insulating lining 9 and in the cover plate 8 in such a way that it exposes a corner part of the bottom plate 7 . Secondary anchoring members include a base fixed to the support wall and a stem extending in the thickness direction of the tank wall. The base may be hollow, for example, with an opening through which the stem passes and a nut screwing into the end of the stem received in the hollow base to keep the stem secured to the base and thus the support wall. ) is included. In another embodiment, the secondary anchoring member may take the form of a stem welded to the inner hull.

In one embodiment, the recesses are located in corner zones. The edge portion of the bottom plate 7 includes a notch to allow passage of the stem of the secondary fixing member. A secondary bearing plate is retained and coupled to the stem as a nut is screwed onto the inner end of the stem opposite the base. This secondary bearing plate supports the edge portion of the bottom plate 7 of the adjacent secondary thermal insulation panel 5, for example, four adjacent secondary thermal insulation panels 5, so that the secondary thermal insulation panel 5 is fixed to the supporting wall. In one alternative, the secondary bearing plate may support the secondary thermal insulation panel 5 via a batten bearing in the corner portion of the bottom plate 7 .

In another alternative, the recesses are located on two sides of the secondary thermal insulation panel 5 , and the secondary fixing member comprises two secondary thermal insulation panels adjacent in the width or length direction of the secondary thermal insulation panel 5 ( 5) located in these recesses between

The cover plate 8 comprises grooves on its inner surface, ie on the surface opposite the insulating lining 9 , for receiving welding supports 6 .

The structure of the secondary heat insulation panel 5 and the secondary fixing member has been described above as an example. Accordingly, in another embodiment, the secondary thermal insulation panel 5 may have a different general structure, for example the structure described in WO2012/127141. The secondary thermal insulation panel 7 in this case extends in the thickness direction of the tank wall between the bottom plate, the cover plate and the bottom plate and the cover plate, and between the bottom plate and the cover plate is made of pearlite, glass wool, rock wool ( Rock wool) is made in the form of a case comprising a support web (support webs) that separates a plurality of compartments filled with an insulating lining.

In another embodiment, the secondary insulating panel includes a bottom plate, a cover plate, and an intermediate plate interposed between the bottom plate and the cover plate. The insulating lining comprises a first layer of insulating lining interposed between the bottom plate and the intermediate plate and a second layer of insulating lining interposed between the intermediate plate and the cover plate. The first layer of insulating lining is adhesively bonded to, for example, the bottom plate and the intermediate plate. The second insulating lining layer is adhesively bonded to, for example, the intermediate plate and the cover plate. In this embodiment, the recess can be made only in the cover plate and in the second insulating lining layer, the secondary bearing plate supporting the exposed part of the intermediate plate. In addition, a notch for the passage of the stem is made in the middle plate, the first insulating lining layer and the bottom plate. Such secondary insulating panels are described, for example, in WO2014/096600.

In one embodiment, the secondary insulation panel is adhesively bonded to the supporting wall, for example by means of the mastic beads mentioned above. In this case, the secondary fixing member and the recess for accommodating it may be omitted.

1 , the secondary sealing membrane 2 may comprise a continuous layer of strakes 10 made of metal with raised edges. The strakes 10 are welded by the raised edges of parallel welding supports 6 fixed in grooves made in the cover plate 8 of the secondary insulating panel 5 . For example, the strake 10 is generally made of Invar®, an alloy of iron and nickel with a coefficient of expansion, between 1.2 Х 10-6 and 2 Х 10-6 K-1. It is also possible to use alloys of iron and manganese with a coefficient of expansion of generally about 7 to 9 Х 10-6 K-1.

The primary thermal insulation barrier 5 comprises a plurality of primary thermal insulation panels 11 which are fixed to the supporting wall by primary fixing members 12 which will be described in more detail below. The primary thermal insulation panels 11 have a generally parallelepiped shape and are arranged side by side to form a primary thermal insulation barrier 3 . In addition, their dimensions in terms of width, length or thickness may be the same as or different from those of the secondary thermal insulation panel 5 . In particular, in the thickness direction of the tank walls, their thickness may be smaller than that of the secondary heat insulating panel 5 . Each primary insulating panel 11 is positioned offset from the secondary insulating panel 5 on which they rest. Accordingly, the adjacent edges of the primary thermal insulation panel 11 are grouped in a line on the cover plate 8 of the secondary thermal insulation panel 5 on which the primary thermal insulation panel 11 rests.

The primary thermal insulation panel 11 may have a multilayer structure similar to that of the secondary thermal insulation panel 5 . Thus, in the example shown, the primary insulating panel 11 is formed continuously in the thickness direction of the tank wall, for example, with a bottom plate 13 made of plywood, with a primary insulating lining 14 , for example and a bottom plate 15 made of plywood. The primary insulating lining consists, for example, of a layer of insulating polymer foam, such as a polyurethane-based foam optionally reinforced with fibers. The insulating lining 14 is preferably adhesively bonded to the bottom plate 13 and the cover plate 15 .

The primary insulating panel 11 comprises recesses in its edge region such that the bottom plate 13 protrudes against the primary insulating lining 14 and the cover plate 15 . The bottom plate 13 thus forms a bearing zone which comes into interaction with the primary bearing plate 16 of the primary fixing member 12 in the corner region of the primary insulating panel 11 . In the embodiment shown in FIG. 3 , wedges 17 are added to the bottom plate 13 , which wedges 17 are similar in shape to the bearing section and are 1 to secure the primary thermal insulation panel 11 . It interacts with the car bearing plate 16 .

The bottom plate 13 of the primary insulating panel 11 includes grooves 18 for receiving the raised edges of the strikes 10 of the secondary sealing membrane 2 . The cover plate 15 comprises anchoring strips 19 shown in FIG. 1 for fixing the primary sealing membrane 4 . These fastening strips 19 are received in counterbores made in the inner surface of the cover plate 15 . The primary insulation panel 11 may further include relaxation slots 20 made in the inner portion of the cover plate 15 and the primary insulation lining 14 . This relief slot 20 has the purpose of preventing deformation or damage to the primary insulating panel 11 that may occur as a result of a difference in shrinkage between the cover plate 15 and the primary insulating lining 14 . This relief slot 20 also distorts the corrugations 21 to the primary insulating barrier 3 , in the case of a primary sealing membrane 4 comprising corrugations 21 , as will be described below. Prevents stresses from being created in the sealing membrane 4 .

The structure of the primary insulation panel 11 has been described above as an example. Accordingly, in another embodiment, the primary insulation panel 11 may have a different general structure, for example, the structure described in WO2012/127141.

In another embodiment, the primary thermal insulation barrier 3 comprises primary thermal insulation panels having at least two different types of construction, for example the two constructions mentioned above, depending on where they are mounted in the tank.

The primary sealing membrane 4 comprises a continuous layer of a rectangular metal sheet having two rows of pleats 21 perpendicular to each other. Rectangular metal sheets are welded together to form small overlap areas along the edges as is known. The rectangular metal sheet preferably has dimensions of width and length equal to an integer multiple of the spacing between the corrugations and an integer multiple of the dimension of the primary thermal insulation panel 11 .

The primary fastening member 12 is described in Ahi with reference to FIGS. 3 to 5 . 3 shows a detailed view of the primary fastening member 12 shown in FIG. 2 with reference number B. FIG. Moreover, in FIGS. 4 and 5 , the nut 32 and bearing plate 16 are not shown. 3-5 , a single primary fastening member 12 is shown, the description of which is given below for one, several, or It can be applied similarly to all.

As described above, in the embodiment shown in FIGS. 1 to 5 , the primary insulating panel 11 is fixed to the supporting wall by means of the secondary insulating panel 5 . For this purpose, the cover plate 8 of the secondary thermal insulation panel 5 comprises a fixing plate 22 . This fixing plate 22 is received in a recess 23 formed in the cover plate 8 .

The recess 23 has an inner section 24 having a first diameter and an outer section 25 having a second diameter. The second diameter is such that the outer section 25 of the recess 23 forms lateral reinforcements which are inserted between the insulating lining 9 and the portion of the cover plate 8 surrounding the inner section 24 . larger than the first diameter.

The fixing plate 22 has a shape complementary to the recess 23 . The inner surface 26 of the fixing plate 22 is flush with the inner surface 27 of the cover plate 8 of the secondary thermal insulation panel 5 . The fixing plate 22 thus forms, together with the cover plate 8 , a substantially continuous plane in which the secondary sealing membrane 2 lies. Furthermore, the outer section 28 of the fixing plate 22 is received in the outer section 25 of the recess 23 and inserted between the cover plate 8 and the insulating lining 9 . The fixing plate 22 is preferably adhesively bonded to the thermal insulation lining 9 of the secondary thermal insulation panel. Accordingly, movement of the fixing plate 22 in the thickness direction of the tank wall is blocked. The fixing plate 22 further comprises a threaded central housing 29 .

The primary fixing member 12 includes a base 30 , a stem 31 , a primary bearing plate 16 and a nut 32 .

The base 30 has external threads and is screwed into the central housing 29 of the fixing plate 22 . That is, the base 30 of the primary fixing member 12 is fixed to the fixing plate 22 .

The stem 31 extends from the base 30 toward the inside of the tank in the thickness direction of the tank wall. The stem 31 passes through an opening formed in the secondary sealing membrane 2 . 1 to 3 , this stem 31 extends in a space separating the edges of the two primary heat insulating panels 11 .

The primary bearing plate 16 has a central passage 60 . This primary bearing plate 16 is coupled to the stem 31 . The primary bearing plate 16 supports wedges 17 which are arranged in the protruding part of the bottom plate 13 of the primary thermal insulation panel 11 with which the primary fixing member 12 interacts. Also, the inner end of the stem 31 opposite the base 30 is threaded, and a nut 32 is threaded into the threaded inner end of the stem 31 to provide a primary bearing plate 16 on the wedge 17. ) is pressurized. In the embodiment shown in FIG. 3 , elastic washers 33 , for example Belleville washers, are inserted between the primary bearing plate 16 and the nut 32 .

In order to ensure the sealing of the secondary sealing membrane 2 at the opening of the secondary sealing membrane 2 through which the stem 31 passes, the primary fixing member 12 is further provided with a sealing washer 34 . include

This sealing washer (34) comprises an annular body (35) having a central opening (36). The sealing washer 34 further comprises a collar 37 extending radially outward from an outer portion of the radially outer face of the annular body 35 . Furthermore, the inner face 38 of the annular body 35 includes ribs 39 protruding in the thickness direction of the tank wall. These ribs 39 extend from a radially inner portion of the inner surface 38 . The collar 37 is formed, for example, by the perimeter of the annular body 35 .

The sealing washer 34 is coupled to the stem 31 , which passes through the central opening 36 of the sealing washer 34 . The sealing washer 34 is inserted between the secondary sealing membrane 2 and the primary bearing plate 16 . The central opening 36 of the sealing washer 34 has a diameter greater than the diameter of the portion of the stem 31 passing through the central opening 36 . Accordingly, a transverse clearance, that is, a clearance in a direction perpendicular to the thickness direction of the tank wall, forms a radial inner surface defining the annular body 35 and the central opening 36 and the stem 31 . separate This clearance causes the seal washer 34 to move transversely relative to the stem 31 , thus allowing the seal washer 34 to move relative to the primary bearing plate 16 .

In an embodiment not shown, the central opening is not circular and has a dimension greater than the transverse dimension of the stem 31 in at least one transverse direction. In this embodiment, the at least one transverse gap separates the central opening 36 from the stem such that the sealing washer can move in the at least one transverse direction relative to the stem 31 .

A collar 37 is sealingly fixed on the secondary sealing membrane 2 around the opening of the secondary sealing membrane 2 . This is achieved, for example, by welding.

The primary anchoring member 12 includes an anchoring shoulder 40 projecting radially outward from the stem 31 . This fixed shoulder 40 is inserted between the sealing washer 34 and the primary bearing plate 16 . The anchoring shoulder 40 has a flat anchoring surface 41 extending in a plane perpendicular to the thickness direction of the tank wall. This fastening surface 41 faces the interior of the tank.

The primary fixation member 12 includes a deformable seal sealingly connecting the stem 31 and the sealing washer 34 . This deformable seal comprises bellows 42 . The inner axial end of this bellows 42 is sealingly fixed to the stem 31 . The outer axial end of this bellows 42 is sealingly fixed on a sealing washer 34 . More specifically, the inner axial end of the bellows 42 is sealingly fixed on the anchoring surface 41 of the anchoring shoulder 40 . The outer axial end of the bellows 42 is sealingly fixed on a rib 39 projecting from the inner surface 38 of the annular body 35 . The inner axial end of the bellows 42 is for example welded to the stem 31 . The outer axial end of the bellows 42 is for example welded to a sealing washer 34 .

This bellows 42 has deformable folds 61, numbered 3 in the embodiment shown in FIG. 3 . In a manner not shown, the number of folds 61 of the bellows 42 is not limited to three but may be more depending on the space between the shoulder 40 and the surface 38 of the collar 37 . Accordingly, the bellows 42 may have 3 to 32 folds 61, ideally 6 folds 61 and 24 folds 61 depending on the space, and the space may for example 20 to 45 mm. Bellows 42 is substantially cylindrical. The folds 61 forming the bellows 42 have the same dimensions. This bellows 42 is made of, for example, stainless steel. The bellows 42 has a thin thickness, preferably less than 1 mm, for example 0.1 to 0.5 mm, more particularly 0.1 mm to 0.3 mm, in order to ensure flexibility.

This bellows 42 forms a flexible, deformable and sealed connection between the stem 31 and the sealing washer 34 . The flexible, deformable connection coupled with the gap between the seal washer 34 and the stem 31 allows relative movement between the seal washer 34 and the stem 31 under sealed conditions. Therefore, since the sealing washer 34 is sealingly fixed to the secondary sealing membrane 2 and the stem 31 with the primary bearing plate 16 supports the primary insulating panel 11, the secondary sealing membrane ( The relative movement between the secondary sealing membrane 2 and the secondary insulating panel 5 and/or the primary insulating panel 11 can be achieved without risk of damage to 2) or loss of the seal of the secondary sealing membrane 2 . It is possible.

In particular, when the stem 31 is fixed to the secondary insulation panel, movement and/or deformation of the secondary insulation panel 5 is possible, and at the same time, such movement and/or deformation causes the secondary sealing membrane 2 or sealing No stress is applied to the connection between the washer 34 and the secondary sealing membrane 2 .

This relative movement between the secondary insulating panel 5 and/or the primary insulating panel 11 and the secondary sealing membrane 2 is the result of contraction differentials, the secondary insulating barrier 1 and/or It may occur as a result of deformation of the supporting walls, or indeed as a result of stresses exerted on the primary insulating panel 11 due to movement of liquid in the tank.

On the one hand, for example, to protect the bellows 42 while constructing the tank and mounting the primary fixing member 12 , the primary fixing member includes a bell 43 . This bell 43 includes a mounting portion 44 and a protective portion 45 . This bell 43 may be combined with various types of bellows 42 described above and below.

The mounting portion 44 has a flat shape and a central opening. The bell 43 is mounted on a stem 31 of the primary fixing member 12 , said stem passing through the central opening of the mounting portion 44 . The mounting part is inserted between the fixed shoulder 40 and the primary bearing plate 16 . The bell is thus prevented from moving in the thickness direction of the tank wall by means of the primary bearing plate 16 on the one hand and the fixing surface 41 on the other hand.

The protective portion 45 is hollow and includes an inner end adjacent a peripheral edge of the mounting portion 44 . The protective part 45 extends from its inner end along the bellows 42 in the direction of the sealing washer 34 , the bellows 42 being received in the hollow protective part 45 . The protective part 45 is also flared in such a way that the outer end of the protective part 45 is arranged in line with the collar 37 of the sealing washer 34 . Accordingly, the bell 43 entirely surrounds the bellows 42 from the inner end of the bellows 42 at the securing surface 41 to the outer end of the bellows 42 secured to the ribs 39 .

The outer end of the protective part 45 has lips 46 extending in a plane perpendicular to the thickness direction of the tank wall. This lip 46 defines a stop surface 47 positioned towards the collar 37 . This stop surface 47 prevents movement of the collar 37 and hence the sealing washer 34 towards the inside of the tank, and the bell 42 is at the abutment of the mounting portion 44 on the primary bearing plate 16 . blocked by itself.

Therefore, since the collar 37 is sealingly fixed to the secondary sealing membrane 2 , when deformation of the supporting wall occurs or overpressure occurs in the secondary sealing membrane 2 , the primary fixing Local deformation of the secondary sealing membrane 2 in the element 12 is blocked by the abutment of the collar 37 of the sealing washer 34 on the stop surface 47 .

In another embodiment, the mounting portion 44 of the bell 43 is secured to the stem by, for example, welding.

In an embodiment not shown, the primary thermal insulation panel 11 and the secondary thermal insulation panel 5 have the same dimensions and the corners of the secondary thermal insulation panel 5 are together with the corners of the primary thermal insulation panel 11 . arranged to be aligned in the thickness direction of the tank wall. In this embodiment, the primary fixing member 12 is fixed directly to the secondary fixing member and not to the secondary insulating panel 5 . Such a configuration is described, for example, in WO201409600, which discloses a joint anchoring device for a secondary insulating panel 5 and for a primary insulating panel 11 , wherein the base of the primary fastening member 12 ( 30) is fixed to one end of the secondary fixing member. Therefore, in this embodiment, the primary fixing member as described above, the base 30 of the primary fixing member 12 is attached to the fixing plate 22 accommodated in the cover plate 8 of the secondary heat insulation panel 5 . It is not fixed, but is fixed to the base plate fixed to the inner end of the secondary fixing member.

6 shows a primary fixing member 12 according to a second embodiment. Elements that are the same as or perform the same function as those described above with reference to FIGS. 1 to 5 have the same reference numerals.

The second embodiment differs from the embodiment shown in Figs. 1 to 5 in that the annular body of the sealing washer has an inclined, ie, a radially outer surface inclined with respect to the thickness direction of the tank wall.

7 shows a primary fixing member 12 according to a third embodiment. Elements that are the same as or perform the same function as those described above with reference to FIGS. 1 to 5 have the same reference numerals.

The third embodiment differs from the embodiment shown in FIGS. 1 to 5 in that the bellows 42 is flared. Accordingly, the folds 61 forming the bellows 42 extend from the inner axial end of the bellows 42 fixed to the fastening surface 41 to the outer axial of the bellows 42 fixed to the sealing washer 34 . It has dimensions that increase towards the end.

Further, in the third embodiment, the inner surface 38 of the annular body 35 of the sealing washer 34 does not include ribs 39, and the inner surface 38 is flat. In this third embodiment, the outer axial end of the bellows 42 is fixed directly to the flat inner surface 38 . In particular, since the bellows 42 has a flattened shape, the outer axial end of the bellows 42 is secured to the radially outer peripheral edge of the inner surface 38 .

This third embodiment is different from the embodiments described with reference to FIGS. 1 to 5 in that the primary fixing member 12 does not include the bell 43 . However, these bells 43 may be added.

In this third embodiment, the stem 31 has a shoulder 48 projecting laterally. This shoulder 48 is inserted between the fixed shoulder 40 and the sealing washer 34 . Moreover, this shoulder 48 has at least one transverse dimension greater than the dimension of the central opening of the sealing washer 34 . This shoulder 48 thus has an outer surface 49 facing the inner surface 38 of the annular body 35 of the sealing washer 34 . That is, the peripheral portion of this outer surface 49 forms the stop surface 47 . This shoulder 48 thus acts as a stop for the sealing washer 34 , blocking the movement of the sealing washer 34 into the tank interior and preventing local deformation of the secondary sealing membrane 2 . .

8 shows the primary fixing member 12 according to the fourth embodiment. Elements that are the same as or perform the same function as those described above with reference to FIGS. 1 to 5 have the same reference numerals.

In the fourth embodiment, the primary anchoring plate 16 is replaced by an anchoring cross 54 . This fixed cross 54 has a mounting part 55 and a plurality of bearing legs 56 , for example four bearing legs 56 as shown in FIGS. 7 and 8 of WO2014/057221 . .

The mounting portion 55 of the fixed cross 54 is flat and extends in a plane perpendicular to the thickness direction of the tank wall. This mounting portion 55 has a central opening through which the stem 31 passes, and a fixing cross 54 is mounted to the stem 31 .

Each bearing leg 56 has an inner end adjacent a peripheral edge of the mounting portion 55 . Each bearing leg 56 extends from a mounting portion 55 to a bearing surface 57 formed by a projecting portion of the bottom plate 13 of the primary thermal insulation panel 11 . The outer end of the bearing leg 56 includes a lip 58 extending in a plane perpendicular to the thickness direction of the tank wall. This lip 58 bears the bearing surface 57 in such a way that it holds the primary insulating panel 11 on the secondary sealing membrane 2 .

This fixed cross 54 provides a degree of protection for the bellows 42 similar to the protective bell 43 described above with reference to FIGS. 1 to 5 .

In this fourth embodiment, the inner end of the bellows 42 is fastened to the lateral face 59 of the fixed shoulder 40 , for example a recessed portion formed for this purpose in the outer part of the side surface 59 . do.

10 to 12 show the primary fixing member 12 according to the fifth embodiment. In these drawings, elements identical to or performing the same functions as those described above with reference to FIGS. 1 to 5 have the same reference numerals.

In this fifth embodiment, the protective portion 45 of the bell 43 is cylindrical and has a generatrix parallel to the thickness direction of the tank wall. The outer end of the protective portion 45 of the bell 43 is arranged in line with the inner surface 38 of the annular body 35 . That is, the stop surface 47 formed by the lip 46 of the outer end of the protective portion 45 interacts with the inner surface 38 of the annular body 35 so that the sealing washer 34 moves into the tank. block that The collar 37 projects radially outward from the annular body 35 beyond the lip 46 . Furthermore, the inner axial end of the bellows 42 is sealingly fixed to the outer surface of the fixed shoulder 40 , ie the side of the fixed shoulder 40 facing the sealing washer 34 , for example by welding.

When liquefied natural gas (LNG) is stored in tanks, movement of the LNG inside the tank, for example associated with the movement of the carrier on which the tank is installed, can cause lateral stresses in the primary insulation panel. In general, movement of the LNG in the tank can apply lateral stress to the pleats 21 of the primary sealing membrane 4 . This lateral stress on the pleats 21 is transmitted to the primary insulating panel 11 to which the primary sealing membrane 4 is fixed. Under the influence of this stress, the primary insulating panel 11 tends to move laterally, ie in a plane perpendicular to the thickness direction of the tank wall, and thus has a tendency to apply stress to the primary fixing member 12 .

Since the collar 37 projects radially outwardly from the annular body 35 beyond the lip 46 of the bell 43 , the bottom plate 13 of the primary thermal insulation panel 11 is ) may come into contact with the collar 37 during movement. When the bottom plate 13 is thus bonded to the collar 37 , it causes significant stress in the sealed connection between the collar 37 and the secondary sealing membrane 2 , which in turn causes the secondary sealing membrane 2 . stresses that could threaten the integrity of the

In order to prevent the force due to the lateral movement of the primary insulation panel 11 from being absorbed by the sealing washer 34 , the fifth embodiment includes a transfer wedge 62 . The transfer wedge 62 makes it possible to transmit a transverse force to the stem 31 and its support, for example a secondary insulating barrier. Moreover, to allow sufficient mounting tolerance and to transmit forces from the primary insulating panel to the stem 31, the lateral dimension of the wedge is smaller than the space between adjacent primary insulating panels.

In this case, the transfer wedge 62 includes a base 63 , a surround 64 , and wings 65 .

The base 63 has a flat shape extending perpendicular to the thickness direction of the tank wall. The base 63 is circular, and its center is coaxial with the stem 31 . The base 63 has a central opening 66 . This central opening 66 is circular and coaxial with the stem 31 . The dimension of the central opening 66 is greater than the dimension of the collar 37 such that space separates the base 63 from the collar 37 .

The base 63 rests on the secondary sealing membrane 2 around the collar 37 . The bottom plate 13 of the primary insulating panel 11 cooperating with the primary fixing member 12 may have an outer counterbore 67 for receiving the base 63 .

Surround 64 includes an outer skirt 68 and an inner skirt 69 connected by a central plateau 82 .

The outer skirt 68 has a circular cylindrical wall with generatrix parallel to the thickness direction of the tank wall. This outer skirt 68 extends from the inner periphery of the base 63 , ie from the edge of the central opening 66 of the base 63 . The outer skirt 68 extends inwardly in the thickness direction of the tank wall over its thickness, the thickness of which is greater than or equal to the thickness considered in the thickness direction of the tank wall of the annular body 35 . Thus, the inner end of the outer skirt 68 is radially juxtaposed with the protective portion 45 of the bell 43 .

A central plateau 82 extends in a plane perpendicular to the thickness direction of the tank wall. This central flat portion 82 extends radially inward from the inner end of the outer skirt 68 . The central flat portion 82 includes a central opening 83 having an inner diameter that is slightly greater than the outer diameter of the protective portion 45 of the bell. Thus, the central flat portion 82 surrounds the protective portion 45 of the bell 43 .

The inner skirt 69 has a circular cylindrical wall with busbars parallel to the thickness direction of the tank wall. This inner skirt 69 extends from the inner periphery of the central flat portion 82 , ie from the edge of the central flat portion 82 defining the central opening 83 . The inner skirt 69 extends towards the interior of the tank over a thickness less than the thickness of the protective portion 45 of the bell 43 . Thus, the inner skirt 69 surrounds the protective portion 45 of the bell 43 over a portion of the thickness of the protective portion 45 .

Typically, a surround 64 surrounds the collar 37 and forms a housing in which the collar 37 is received in the gap, as shown in FIGS. 11 and 12 , protecting the collar 37 .

Therefore, when the primary thermal insulation panel 11 experiences a stress that moves the primary thermal insulation panel 11 laterally, the bottom plate 13 of the primary thermal insulation panel 11 is attached to the transfer wedge 62 . against and generally against the base 63 and/or the outer skirt 63 . The conveying wedge 62 surrounds the bell 43 , and since the distance separating the conveying wedge 62 from the bell 43 is less than the distance separating the conveying wedge 62 from the collar 37 , the conveying wedge 62 ) abuts the bell (43) without creating significant stress on the collar (37). That is, the force due to this lateral movement of the primary thermal insulation panel 11 is transmitted through the bottom plate 13 of the primary thermal insulation panel 11 , which applies a force to the transfer wedge 62 , which A force is then applied to the bell (43) and the stem (31). Accordingly, the transfer wedge 62 prevents the force due to the lateral movement of the primary insulating panel 11 from being transmitted through the collar 37, so that the sealed seal between the collar 37 and the secondary sealing membrane 2 is provided. Limit the stress at the joint.

In the embodiment shown in FIGS. 10-12 , the transfer wedge 62 further comprises four wings 65 , which facilitate positioning of the transfer wedge 62 with respect to the adjacent primary insulating panel 11 . . These positioning wings 65 are distributed circumferentially at regular intervals around the surround 64 . These vanes 65 extend radially from the surround 64 parallel to the thickness direction of the tank wall. Each wing 65 is received between two primary insulating panels 11 which interact with a primary fastening member 12 . These wings 65 separate sections that independently wedge each of the primary insulating panels 11 .

In an embodiment not shown, the outer skirt 68 extends beyond the bottom plate 13 of the primary insulating panel 11 towards the interior of the tank. Thus, upon lateral movement of the primary thermal insulation panel 11 , the thermal insulation lining 14 also provides an outer skirt 68 for guiding the forces resulting from the lateral movement of the primary thermal insulation panel 11 to the conveying wedge 62 . ) will come into contact with

13 and 14 show the primary fixing member 12 according to the sixth embodiment.

This sixth embodiment differs from the fifth embodiment shown with reference to FIGS. 10 to 12 in that the outer end of the protective portion 45 of the bell 43 is arranged in line with the collar 37 . Moreover, the lip 46 of the outer end of the protective portion 45 projects radially beyond the collar 37 . Thus, the stop surface 47 formed by the lip 46 of the outer end of the protective portion 45 interacts with the inner surface of the collar 37 to block the sealing washer 34 from moving into the tank.

In this embodiment, the transfer wedge 62 is formed by a block 84 . This block 84 includes a central opening. This central opening has an inner diameter that is slightly larger than the outer diameter of the protective portion 45 of the bell 43 in such a way that the block 84 surrounds the protective portion 45 of the bell 43 .

The block 84 has a thickness along the thickness direction of the tank wall, which is thinner than the thickness of the bottom plate 13 of the adjacent primary heat insulation panel 11, so that the inner surface of the block 84 has a thickness along the thickness direction of the tank wall. is arranged on the outside of the inner surface of the bottom plate (13). Moreover, in the embodiment shown in FIG. 13 , the block 84 rests on the inner surface of the lip 46 of the protective part 45 of the bell 43 .

The peripheral lateral face of the block 84 is shaped generally complementary to a recess formed in the bottom plate 13 of the primary insulating panel 11 which interacts with the primary fastening member 12 . has That is, the distance separating the bottom plate 13 and the block 84 of the primary heat insulating panel 11 substantially corresponds to a mounting clearance. Thus, lateral movement of the primary insulating panel 11 presses the peripheral side of the block 84 from the beginning of its movement.

Thus, upon lateral movement of the primary insulating panel 11 , the bottom plate 13 of the primary insulating panel 11 abuts against the transport wedge 62 , in particular against the peripheral side of the block 84 , The transfer wedge abuts the bell 43 and the stem 31 without substantially stressing the collar 37 . Thus, the stress exerted by the primary insulating panel 11 on the transfer wedge 62 is transmitted substantially to the stem 31 without passing through the connection between the collar 37 and the secondary sealing membrane 2 .

An example of a method of mounting the primary fixing member is described below with reference to FIGS. 15 to 17 . In these FIGS. 15 to 17 and the following description, elements that are the same as or perform the same functions as those described above have the same reference numerals.

As described above with reference to FIGS. 1 to 5 , the fixing plate 22 is received in the recess 23 formed in the cover plate 8 of the secondary heat insulating panel 5 . The inner surface 26 of the fixing plate 22 is flush with the inner surface 27 of the cover plate 8 of the secondary thermal insulation panel 5 . The fastening plate 22 further comprises a threaded central housing 29 intended to receive the base 30 of the primary fastening member 12 .

Preferably, the primary fixation member 12 may be at least partially prefabricated. A prefabricated portion of the primary fixation member 12 is, for example, as shown in FIG. 16 , a base 30 , a stem 31 , and a bellows having an inner axial end secured to a fixed shoulder 40 . (42), and a sealing washer (34) to which the outer axial end of the bellows is secured.

However, with this prefabricated primary fastening member 12 , the sealing washer 34 is integrated into the rotation of the stem 31 via the bellows 42 . Accordingly, when the stem 31 rotates to screw the base 30 into the threaded central housing 29, the sealing washer 34 also rotates. However, this rotation of the sealing washer 34 may cause friction between the secondary sealing membrane 2 and the outer surface of the sealing washer 34 , particularly at the end screwing the base 30 to the housing 29 . there is. Such friction may cause torsion of the bellows 42 , which may damage the seal of the bellows 42 , including the bellows 42 .

In order to prevent twisting of the bellows 42 when screwing the base 30 to the housing 29, the body 35 of the sealing washer 34 has a collar 37 and an inner surface of the body 35 ( 38) and includes flat portions 85 (flat portions) on the sides connecting them. Likewise, the fixed shoulder 40 also includes a flat portion 86 . The flat portion 85 of the sealing washer 34 and the flat portion 86 of the fixed shoulder 40 preferably extend in the same plane.

A method for mounting the primary fixation member 12 includes the use of a socket wrench 87 comprising an inner surface 88 complementary to the flat portions 85 , 86 . Moreover, the socket of the wrench 87 preferably has a height greater than the height of the stem 31 and greater than or equal to the distance between the inner axial end of the stem and the flat portion 85 of the seal washer 34 . Thus, due to the complementarity between the inner surface 88 of the wrench and the flat portions 85 , 86 , rotation of the wrench 87 rotates both the base 30 and the sealing washer 34 , including the stem 31 . make it In FIG. 16 , the fixed shoulder 40 and the body 35 include six flat portions 85 , 86 , but the number and dimensions of these flat portions may vary, the primary anchoring member 12 comprising one, It may include two or more flat portions 85 and one, two or more flat portions 85 , 86 complementary to the inner surface 88 of the wrench 87 , such that the stem 31 and the base 30 are rotates together when the wrench 87 is used.

To mount the prefabricated part of the primary fastening member 12 to the fastening plate 22 , the prefabricated part is inserted into the socket of the wrench 87 . The wrench 87 is rotated to screw the base 30 to the housing 29 . Since the sealing washer 34 rotates together with the stem 31 , the friction between the sealing washer 34 and the secondary sealing membrane 2 does not cause the bellows 42 to twist.

When the base 30 is fully screwed into the housing 29, a bell 43 may be added to the stem 31 as shown in FIG. Alternatively, the prefabricated portion of the fastening member may further comprise a bell 43 when fixed to the stem 31 , for example by welding.

In this alternative shown in FIG. 17 , the bell 43 comprises a flat portion 89 similar to the flat portion 86 of the fixed shoulder 40 . Furthermore, the sealing washer 34 , in particular the flat part 85 , is arranged radially beyond the lip 46 of the bell 43 . Thus, the inner surface 88 of the wrench 87 is coupled to the flat portion of the seal washer 34 and the bell ( 43), so as not to twist the bellows 42.

The techniques described above for producing sealed and insulated tanks can be used in various types of storage tanks, for example to build LNG storage tanks on floating structures such as onshore facilities or LNG carriers.

Referring to FIG. 9 , a partial cutaway view of the LNG carrier 70 shows a generally prismatic sealed and insulated tank 71 mounted on the double hull 72 of the carrier. The wall of the tank 71 comprises a primary sealing barrier intended to come into contact with the LNG contained in the tank, a secondary sealing barrier disposed between the primary sealing barrier and the double hull 72 of the carrier, the primary sealing barrier and and two insulating barriers respectively arranged between the secondary sealing barrier and between the secondary sealing barrier and the double hull 72 .

In a manner known per se, loading/unloading pipelines 73 arranged on the upper deck of the carrier, via suitable connectors, transport LNG cargoes to or from tanks 71 to sea or port terminals for transport. can be connected

9 shows an example of a marine terminal comprising a loading and unloading station 75 , a submersible pipe 76 and an onshore facility 77 . The loading and unloading station 75 is a fixed offshore facility comprising a movable arm 74 and a tower 78 supporting the movable arm 74 . The movable arm 74 carries a bundle of insulated flexible pipes 79 , which can be connected to loading/unloading pipelines 73 . The orientable movable arm 74 can be adjusted to fit any size LNG carrier. A connecting pipe (not shown) extends into the tower 78 . The loading and unloading station 75 allows loading and unloading of the LNG carriers 70 from or to an onshore facility 77 . The facility includes a tank 80 for storing liquefied gas and a connecting pipe 81 connected to a loading or unloading station 75 by means of a submersible pipe 76. An underwater pipe 76 may be connected to a loading or unloading station 75 over a large distance (e.g., 5 km to maintain a large separation distance of the LNG carrier 70 from shore during loading and unloading operations). Allows delivery of liquefied gas over long distances between onshore facilities 77 .

To create the pressure necessary to deliver the liquefied gas, pumps mounted on carrier 70 and/or pumps mounted on shore facility 77 and/or pumps mounted on loading and unloading stations 75 are used. .

While the invention has been described in connection with several specific embodiments, it will be apparent that, when included in the scope of the invention, the invention is not limited thereto and includes all technical equivalents of the instrumentalities described and combinations thereof.

The use of the verbs "comprise" or "have" and its conjugations does not exclude the presence of other elements or steps other than those specified in a claim.

Reference signs placed between parentheses in a claim should not be construed as a limitation of the claim.

Claims (19)

A sealed and insulated tank comprising a tank wall, the tank comprising:
The tank wall is continuous from the outside of the tank to the inside of the tank in the thickness direction of the tank wall, the secondary insulating barrier (1) fixed to the supporting wall, and the secondary sealing lying on the secondary insulating barrier (1) Membrane (2), a primary insulating barrier (3) overlying the secondary sealing membrane (2), a primary sealing membrane overlying the primary insulating barrier (3) and in contact with the product contained within the tank (4) - the primary sealing membrane (4) comprises a plurality of primary insulating panels (11) arranged side by side;
The tank further comprises a plurality of primary fixing members (12) adapted to be held directly or indirectly on the support wall, each of the primary fixing members (12) comprising: the secondary sealing membrane (2) interacts with at least one primary thermal insulation panel of the plurality of primary thermal insulation panels 11 in such a way as to retain at least one primary thermal insulation panel 11 in the
The primary fixing member 12,
- a base 30 adapted to be held directly or indirectly on said supporting wall;
- a stem (31) extending in the thickness direction of the tank wall from the base (30) towards the primary sealing membrane (4) and passing through the opening of the secondary sealing membrane (2);
- bearing elements (16, 54) mounted on the stem (31), supporting the primary insulating panel (11) in such a way as to hold the primary insulating panel (11) on the secondary sealing membrane (2);
- a sealing washer (34) coupled to the stem between the bearing element (16) and the opening of the secondary sealing membrane (2) - The sealing washer (34) has a central opening (36) through which the stem (31) passes ), wherein the sealing washer (34) is sealingly fixed to the secondary sealing membrane (2) around the opening of the secondary sealing membrane (2);
- a deformable seal (42) sealingly connecting said seal washer (34) and said stem (31) in a manner allowing relative movement between said seal washer (34) and said stem (31); sealed and insulated tanks.
The method of claim 1,
The central opening 36 of the sealing washer 34 has a transverse dimension that is greater than the transverse dimension of a portion of the stem 31 coupled to the central opening 36 such that the stem 31 has the sealing washer A sealed and insulated tank allowing movement in the central opening (36) of (34) in a direction perpendicular to the thickness direction of the tank wall.
3. The method of claim 1 or 2,
The primary fixing member 12 is configured to prevent the sealing washer 34 from moving towards the primary sealing membrane 4 in the thickness direction of the tank wall with respect to the stem 31 . A stop supported by ( 31 ) - the stop is arranged on the stem ( 31 ) between the bearing element ( 16 ) and the sealing washer ( 34 ), the stop being a stop facing the sealing washer ( 34 ) and having a surface (47).
4. The method of claim 3,
The stem 31 has a shoulder 48 , the shoulder 48 being the center of the sealing washer 34 such that an outer surface 49 of the shoulder 48 forms the stop surface 47 . A sealed and insulated tank projecting laterally from the stem (31) beyond the opening (36).
3. The method of claim 1 or 2,
The primary fixing member (12) further comprises a bell (43) mounted to the stem (31), the bell (43) comprising a mounting portion (44) and a protection portion (45), the mounting portion (44) has a central passage through which the stem (31) passes, the protective part (45) extending from the mounting part (44) towards the sealing washer (34) in the thickness direction of the tank wall, A sealed and insulated tank in which the protective part (45) is hollow and the deformable seal (42) is accommodated in the protective part (45).
6. The method of claim 5,
The primary fixing member 12 is configured to prevent the sealing washer 34 from moving towards the primary sealing membrane 4 in the thickness direction of the tank wall with respect to the stem 31 . (31) further comprising a stop supported by (31), said stop being disposed on said stem (31) between said bearing element (16) and said sealing washer (34), said stoppering said sealing washer (34) a facing stop surface (47);
The outer end of the protective portion (45) opposite the mounting portion (44) forms a stop surface (37) facing the sealing washer (34).
6. The method of claim 5,
A sealed and insulated tank in which the bell (43) is fixed to the stem (31).
6. The method of claim 5,
and a transfer wedge disposed around the bell in a gap between the bell and the adjacent primary insulating panel.
6. The method of claim 5,
The sealing washer 34 includes a flat portion 85 , the bell 43 includes a flat portion 89 , the flat portions wherein the stem 31 and the sealing washer 34 are deformed A sealed and insulated tank gripped by a screw tool to rotate together without possible twisting of the seal ( 42 ).
3. The method of claim 1 or 2,
The deformable seal comprises a deformable bellows 42 , the deformable bellows 42 being hollow and extending axially along the stem 31 , a first axial end of the bellows 42 . is sealingly secured to the stem (31) and the second axial end of the bellows (42) is sealingly secured to the sealing washer (34).
11. The method of claim 10,
The bellows (42) is a sealed and insulated tank having at least three folds.
11. The method of claim 10,
The bellows (42) has an expanded shape, and the second axial end of the bellows (42) fixed to the sealing washer (34) is, A sealed and insulated tank having a circumferential dimension greater than the circumferential dimension of the first axial end.
3. The method of claim 1 or 2,
The base (30) of the primary fixing member (12) is a sealed and insulating tank that is firmly fixed to the secondary thermal insulation barrier (1).
3. The method of claim 1 or 2,
The inner end of the stem (31) opposite the base (30) is threaded, the primary fixing member (12) further comprising a nut (32) screwed into the threaded inner end, the bearing element (16, 54) is inserted between the nut (32) and the base (30) of the primary fixing member (12), the deformable seal is the seal washer (34) and the bearing element (16, 54) ) sealed and insulated tanks inserted between them.
15. The method of claim 14,
A sealed and insulated tank in which a resilient washer (33) is inserted between the nut (32) and the bearing elements (16, 54).
3. The method of claim 1 or 2,
The primary fixing member 12 has a fixing shoulder 40 projecting laterally from the stem 31 , the fixing shoulder 40 having a fixing surface 41 extending in a plane perpendicular to the thickness direction. sealed and insulated tank, wherein the fixing surface (41) faces the bearing elements (16, 54) and the deformable seal is sealingly fixed to the fixing surface (41).
A carrier (70) for the transport of cold liquid products, comprising:
A carrier comprising a double hull (72) and a tank according to claim 1 or 2 arranged in said double hull.
A conveying system for conveying a cold liquid product, comprising:
A carrier (70) according to claim 17, and insulated pipelines (73, 79, 76, 81) arranged to connect the tank installed in the hull of the carrier to a floating or onshore storage facility (77), said and a pump for pumping a flow of cold liquid product through insulated pipelines from a floating or onshore storage facility to the tank of the carrier, or from the tank of the carrier to a floating or onshore storage facility.
A method for loading or unloading a carrier (70) according to claim 17, comprising:
The cold liquid product is transported via insulated pipelines 73 , 79 , 76 , 81 from a floating or onshore storage facility 77 to the tank of the carrier 70 , or the tank 71 of the carrier. ) to a floating or onshore storage facility (77).

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