JP2006137420A - Sealed, thermally insulated tank with juxtaposed non-conducting elements - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed, thermally insulated tank capable of improving the cost of the tank, the capacity of a wall to withstand the pressure, or the heat insulation of the wall. <P>SOLUTION: The sealed, thermally insulated tank consists of at least one tank wall fixed to a hull of a floating structure. The tank walls have insulating barriers consisting essentially of juxtaposed non-conducting elements. Each non-conducting element includes a thermal insulation liner arranged in a shape of a layer parallel to the tank walls, and load-bearing partitions rising through the thickness of the thermal insulation liner in order to take up the compression forces. The heat insulation tank is manufactured in a shape of at least one load-bearing structure in which the load-bearing element of the non-conducting element consists of single piece. The single piece has a connection means to firmly connect the load-bearing elements to each other in at least a highest portion of the load-bearing elements, and at least one load-bearing structure of the non-conducting element has a shape of a section of a hollow contour having a predetermined section in the longitudinal axial direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the manufacture, storage, filling, and marine transportation of cold liquids (eg, liquefied gases, particularly those having a high methane content) consisting of a tank wall fixed to a load carrying structure of a floating structure. And / or relates to the manufacture of sealed, insulated tanks suitable for loading and unloading. The invention also relates to a methane carrier comprising this type of tank.

  Marine transport of liquefied gas at very low temperatures includes vaporization rate per day voyage, which is advantageous to minimize. This means that the insulation of the associated tank should be improved.

  A sealed insulation tank consisting of a tank wall fixed to the ship's load-bearing structure has already been proposed, and this tank wall is continuously in the direction of the thickness from the inside to the outside of the tank. A primary hermetic barrier, a primary adiabatic barrier, a secondary hermetic barrier, and a secondary adiabatic barrier, at least one of these adiabatic barriers consisting essentially of parallel non-conductive elements, each non-conductive The element comprises an insulating liner arranged in the form of a layer parallel to the tank wall, and a load bearing element that rises over the thickness of the insulating liner to absorb compressive forces.

  For example, in U.S. Patent No. 6,047,059, these thermal barriers consist of closed parallelepiped caisson made from plywood and filled with pearlite. On the inside, the caisson includes a parallel load bearing spacer interposed between the cover panel and the base panel to withstand the hydrostatic pressure imparted by the liquid contained in the tank. Unloaded spacers made from plastic foam are placed between these loaded spacers to maintain the relative position of these loaded spacers. The manufacture of this type of caisson (including the assembly of outer walls made from plywood sections and the attachment of spacers) requires a number of assembly operations (especially stapling). Furthermore, the use of powders such as perlite complicates the manufacture of this caisson. This is because this powder generates dust. Therefore, it is necessary to use a high quality and therefore expensive plywood (ie a plywood without knots) so that this caisson is well sealed against dust. In addition, for safety reasons, this powder must be tamped into the caisson at a certain pressure for the purpose of venting all air present and nitrogen must be circulated inside each caisson. is there. All these operations complicate caisson manufacturing and increase costs. Further, if the thickness of the insulation caisson increases with the insulation barrier, the risk of bending the caisson wall and load bearing spacers is significantly increased. If it is desired to increase the flexural strength of the caisson and their internal load bearing spacers, the cross section of these spacers must be increased, thereby increasing the gap between the liquefied gas and the ship's load bearing structure. The thermal bridge established at the same time increases by the same amount. Furthermore, when the thickness of these caissons increases, gas convection is observed inside these caissons, which is very detrimental to good insulation.

  U.S. Patent No. 6,057,034 describes another insulated caisson designed for use in such a tank. In these manufacturing methods, a plurality of low-density foam layers and a plurality of plywoods are alternately stacked, and the height of the stack corresponds to the length of the caisson between each foam layer and each panel. Until the adhesive is placed, the above stack is cut into sections at regular intervals corresponding to the thickness of the caisson in the height direction, and the base panel and top made from plywood It consists in bonding the panels to each side of each section of each stack thus cut. These panels extend perpendicular to the cut panels and they act as spacers. The result of this is a good compromise in terms of flexural strength and insulation, but it will be appreciated that the manufacturing process also requires a number of assembly steps.

Patent document 3 describes a rigid heat insulating material panel comprised of a folded sheet and an envelope. This envelope is filled with granular insulation. The folded sheet forms a framework that reinforces the envelope. The folded sheet is produced by folding a sheet of paper or cardboard in the form of a single piece that serves as a framework for the envelope. Considered alone, this folded sheet is not stiff in the region of the fold that is formed and constitutes a flexible indirect between the panels. For this reason, when the sheet is moved between the two assembly stations, the folded sheet is held in the proper shape by the protrusions and fingers.
French Patent Application Publication No. 2 527 544 French Patent Application Publication No. 2 798 902 U.S. Pat. No. 4,416,715

  The object of the present invention is to propose a tank of this type while improving at least one of the following features without damaging the other of the following features: the cost price of the tank, the wall Ability to withstand pressure, and wall insulation. A further object of the present invention is that the non-conductive element, which improves the characteristics of the wall without impairing its ability to withstand pressure and the insulation of this wall and, if possible, at the same time, is easy to manufacture, Advocate this type of tank.

The present invention provides the following:
(Item 1)
A sealed thermal insulation tank comprising at least one tank wall fixed to the hull (1) of a floating structure, the tank wall being continuous in the direction of thickness from the inside to the outside of the tank A primary sealing barrier (8), a primary insulating barrier (6), a secondary sealing barrier (5), and a secondary insulating barrier (2), wherein at least one of the insulating barriers is in parallel Insulating liners (76, 276, 376a-b, 476) consisting essentially of conductive elements (3, 7), each non-conductive element being arranged in the form of a layer parallel to the tank wall. ), And load-carrying elements (75, 175, 192, 193, 275, 375, 475, 575, 775, 875, 975, 1075, 1175, raised over the thickness of the insulating liner to absorb compressive forces 1275, 375, 1475), wherein the thermal insulation tank comprises at least one load carrying structure (70, 170a, 170b, 270, 370, 470, 500, wherein the load carrying element of the non-conductive element is formed from a single piece. 600, 700, 800, 1300, 1477), the single piece being in each case a connecting means (71, 72, 171, 172, 272, 371, 372, 472, 571, 771, 890, 1371, 1471), the coupling means firmly connecting the load bearing elements together at least at the highest part of the load bearing elements and the at least one load bearing structure (70) of the non-conductive element. , 170a-b, 270, 370, 470), characterized by having the shape of a hollow contour section having a constant cross section in the longitudinal direction. It sealed insulated tank.
(Item 2)
The connecting means of the load carrying structure comprises a panel (71, 72, 171, 172, 272, 371, 372, 472, 571, 771, 1371, 1471), the panel of the non-conductive element Item 2. The sealed insulated tank according to item 1, characterized in that, on the side, it extends parallel to the tank wall and the load carrying element protrudes from the inner surface of the panel.
(Item 3)
The load carrying element of the load carrying structure comprises at least two longitudinal sections (75, 175, 192, 193, 275, 375, 475), the longitudinal sections being at least one of a constant cross-section relative to each other. Item 1 or 2, characterized in that it is arranged at a distance from each other so as to define two cells (73, 173) and can receive said insulating liners (76, 276, 376a-b, 475). Sealed thermal insulation tank.
(Item 4)
The sealed insulated tank according to item 3, characterized in that the longitudinal compartment comprises at least one compartment (75, 175) substantially perpendicular to the tank wall.
(Item 5)
Item 5. The sealed insulated tank according to item 3 or 4, characterized in that the longitudinal section comprises at least one section (192, 193) inclined with respect to the tank wall.
(Item 6)
Item 6. The sealed insulated tank according to item 5, characterized in that the longitudinal section comprises at least two sections (192, 193) having slopes in opposite directions from each other.
(Item 7)
The connecting means of the load carrying structure comprises at least one connecting wall (71, 72, 171, 172, 472) connecting the longitudinal sections (75, 175, 475) over its entire length, the longitudinal axis 7. Sealed according to any one of items 3 to 6, characterized in that the directional compartment has an enlarged portion (68, 168, 468) in the region of the zones connected by the at least one connecting wall. Insulated tank.
(Item 8)
The non-conductive element (70, 170a-b) comprises a base panel and a cover panel, and at least one of the laterally outermost longitudinal sections of the non-conductive element has an open side Any of items 3-7, characterized in that it is at a distance corresponding to at least one of the bottom panel and the cover panel from a lateral edge to define a section cell (74, 174) The sealed heat insulation tank according to item 1.
(Item 9)
The non-conductive element (570) comprises a second panel (572), the second panel being formed separately from the load bearing structure (500) and forming the connecting means The tank according to item 2, characterized in that it is fixed to the end of the load carrying element (575) on the opposite side of the first panel (571).
(Item 10)
10. Sealing according to item 9, characterized in that the inner surface of the second panel has a recess (573) arranged in such a way that it interacts with the load bearing element (575) by coplanar mounting. Insulated tank.
(Item 11)
The second panel (572) has a coefficient of thermal expansion different from that of the load carrying element (575), so that when the tank is cooled, it is mounted flush with the latter. 11. A sealed insulation tank according to item 10, characterized in that a grip is produced between the second panel and the load carrying element.
(Item 12)
The non-conductive element (670) has two load carrying structures (500), the load carrying structures being such that their respective panels have inner surfaces bent towards each other. The load-carrying elements (575) that are arranged at the side and project from the inner surface are in each case paired in the end region located on the opposite side of the panel to form a load-carrying element of the non-conductive element. The sealed thermal insulation tank according to item 2, characterized in that the tank is assembled.
(Item 13)
The thermal insulation piece (680) having a thermal conductivity lower than the thermal conductivity of the load carrying element is characterized in that in each case it is interposed between two assembled load carrying elements, Item 13. The sealed insulation tank according to item 12.
(Item 14)
The load-carrying elements of the two load-carrying structures are in each case assembled in pairs by a connection piece (680), the connection piece having a heat different from the thermal expansion coefficient of the load-carrying element. 14. Sealing according to item 12 or 13, characterized in that it has an expansion coefficient and thereby causes a grip between the connecting piece and the load carrying element (575) when the tank is cooled. Insulated tank.
(Item 15)
At least one load bearing structure (70, 170a-b, 270, 370, 470, 500, 600, 700, 800, 1300, 1477) of the non-conductive element is molded, extruded, pultruded, thermoformed, Item 15. A sealed insulated tank according to any one of items 1 to 14, characterized in that it is manufactured by a forming process selected from the group comprising processes of blow molding, injection molding and rotational molding.
(Item 16)
The at least one thermal barrier (2, 6) composed of the non-conductive elements (70, 170a-b, 870) is in each case formed from a thin sheet metal strip (40) having a low coefficient of expansion. Is covered by one of the sealed barriers (5, 8), the edge of the filament bulges towards the outside of the non-conductive element, the non-conductive element being Each having a cover panel (72, 172, 872) having parallel grooves (78, 178) spaced by the width of the strips on which the welding support (42) is slidably held. The support has continuous wings projecting from the outer surface of the cover panel, and two adjacent plate line raised edges (43) on the two sides of the weld support prevent leakage. Items 1-1, characterized by being welded in a style It sealed insulated tank according to any one of.
(Item 17)
A second retaining member (82-84) integral with the load carrying structure of the ship secures the non-conductive element to provide a secondary insulation barrier (2) to the load carrying structure (1). And a primary holding member (48) connected to the weld support (42) of the secondary sealing barrier (5) holds the primary insulating barrier against the secondary sealing barrier; Item 17. The sealed insulated tank of item 16, wherein the weld support holds the secondary sealed barrier against a cover panel of the non-conductive element of the secondary insulated barrier.
(Item 18)
Item 18. A floating structure comprising the sealed heat insulation tank according to any one of items 1 to 17.
(Item 19)
Item 19. The floating structure according to item 18, comprising a methane carrier.

  A sealed insulation tank consisting of a caisson wall fixed to a load carrying structure (1) of a floating structure, the tank wall being continuous in the direction of thickness from the inside to the outside of the tank A primary sealing barrier (8), a primary insulating barrier (6), a secondary sealing barrier (5) and a secondary insulating barrier (2), at least one of these insulating barriers being in parallel non-conducting Each non-conductive element comprises an insulating liner (76) and a load-carrying element (75) that are raised over the thickness of the insulating liner for the purpose of absorbing compressive forces. To do. This insulating tank is manufactured in the form of at least one load-carrying structure (70) in which the load-carrying element of the non-conductive element is formed from a single piece, and in each case a connecting means connects the load-carrying element to the load-carrying element. It is characterized by being firmly connected together.

  To that end, the subject of the present invention is a sealed insulated tank comprising at least one tank wall fixed to the hull of a floating structure. The tank wall has a primary hermetic barrier, a primary thermal barrier, a secondary hermetic barrier, and a secondary thermal barrier in the direction of the thickness from the inside to the outside of the tank in series. At least one of which consists essentially of parallel non-conductive elements, each non-conductive element being arranged in the form of a layer parallel to this tank wall, and absorbing compressive forces A load-carrying element that rises over the thickness of the insulation liner, the sealed insulation tank comprising at least one load-carrying element, wherein the load-carrying element of the non-conductive element is formed from a single piece Manufactured in the form of an element, this single piece is provided in each case with connecting means, which connect these load-bearing elements together in at least one height portion of the load-bearing element You .

  This type of load-bearing structure formed from a single piece is in terms of stiffness and resistance to bending resistance in the direction of the thickness of the hollow element, ease of formation, thermal insulation and cost price. Both combine various advantageous mechanical properties. Indeed, for a given geometric shape of the load bearing element, their resistance to bending is increased by a rigid internal connection compared to a separate load bearing element. In addition, the manufacture in the form of a single piece of the connection between the load-carrying elements and the load-carrying elements (ie at least a part of these heights) allows distribution in a specific assembly operation, Makes it possible to obtain a relatively rigid load-bearing structure without excessively increasing the cross-section of the elements and / or their thickness, and thus the thermal bridge, and the installation of an insulating liner in a non-conductive element It is characterized by simplification.

  According to a preferred embodiment of the connecting means, the connecting means of the load carrying structure comprises a panel extending parallel to the tank wall on the side of the non-conductive element, the load carrying element comprising the panel Protrudes from the inner surface of the. In other words, in this case, the load carrying structure comprises a base panel or cover panel of non-conductive elements. For convenience, “cover” is the name given to the panel on the side of the non-conductive element facing towards the inside of the tank, and “base” refers to the load bearing structure. The name given to the panel on the surface of the non-conductive element. The load carrying structure thus formed can also include both a base panel and a cover panel.

  According to an advantageous embodiment of the load-carrying structure, the at least one load-carrying structure of the load-carrying element has the shape of a hollow profile section having a constant cross section in the longitudinal direction.

  For example, this type of load bearing structure may be obtained by extrusion or pultrusion of any suitable material. In particular, it is possible to obtain a contoured section of this type with a constant cross section at the outlet where the hollow element is cut to the desired length using a continuous extrusion die, As a result, the size of the corresponding non-conductive element can be easily modified. Multiple shaped cross-sections of contoured sections can be produced.

  The load carrying element can have any shape. According to one advantageous embodiment of the load-carrying element, said load-carrying element of the load-carrying structure comprises at least two longitudinal sections, which sections have at least one cell having a constant cross-section with respect to each other. May be positioned at a distance from each other and receive an insulating liner. This type of compartment serves both as a load-carrying spacer to support the pressure applied to the non-conductive element and as a compartment between the cells. These cells (which may be one, two, three, or higher numbers for each non-conductive element) are particularly In the case of a contoured section, it allows easy insertion of the insulation liner into the non-conductive element via the end.

  Advantageously, the longitudinal section comprises at least one section substantially perpendicular to the tank wall. This type of structure improves the stress distribution across this longitudinal section. The longitudinal cell thus has a substantially rectangular or square cross section.

  Preferably, the longitudinal section comprises at least one section inclined with respect to the tank wall, advantageously comprising at least two sections having inclined surfaces opposite to each other. This type of slanted section not only allows for the absorption of shear stress, but also allows for the absorption of bending and tilting stresses. Thus, it is possible to provide cells having other cross-sectional shapes (eg, trapezoidal or triangular cross-sectional shapes).

  Advantageously, the connecting means of the load bearing structure comprises at least one connecting wall connecting the longitudinal section over its entire length, the longitudinal section connecting with the at least one connecting wall. In the area of the zone, it has an enlarged portion. This type of connecting wall may be parallel to or inclined with respect to the tank wall. This can in particular be a base panel and / or a cover panel. This type of enlargement improves the robustness and rigidity of the corresponding connecting zone.

  According to a particular embodiment of the longitudinal section, the non-conductive element comprises a base panel and a cover panel, and at least of the laterally outermost longitudinal section of the non-conductive element One is at a distance from a lateral edge corresponding to at least one of these base and cover panels for the purpose of defining an end cell having an open lateral surface. This type of end panel (which can be provided on one or both sides of these non-conductive elements) creates a space between the outermost longitudinal sections of two adjacent non-conductive elements To do. This space allows the intersection of the insulation liner to ensure the continuity of the insulation barrier in the region of the interface between the parallel non-conductive elements.

  According to a further embodiment of the load-carrying element, the load-carrying element of the at least one load-carrying structure is small when compared to the dimensions of the non-conductive element in a plane parallel to the tank wall. It has a column with a cross section.

  This type of small cross-sectional column has the advantage that they can be distributed according to local requirements in non-conductive elements. By adapting the number and distribution of load bearing columns, the compressive strength of this non-conductive element can be made more uniform than with prior art spacers in particular. It is also possible to prevent local depression or tightening of the cover panel. This type of pillar may have a hollow or solid cross-section, for which many shapes are possible. In particular, a hollow column with a closed cross section makes it possible to obtain a very good resistance to bending resistance, while at the same time minimizing the effective heat transfer cross section.

  According to a further embodiment of the connecting means, these connecting means comprise an arm extending between the load carrying elements. Advantageously, these arms extend along at least one side of the insulation liner, parallel to the tank wall. When arranged in this manner, these arms serve in addition to the surface of the load-carrying element for securing the possible base panel and / or cover panel, which is formed independently of the load-carrying structure. Give a realistic surface.

  According to a particular embodiment of the load-carrying structure, the at least one load-carrying structure has the form of a box with a peripheral wall projecting entirely around the inner surface of the panel. This type of design allows the installation of an insulation liner in the form of a granular material. However, depending on the construction of this insulation liner, it is also possible to use non-conductive elements that do not have a peripheral wall.

  This non-conductive element may be open or closed. Advantageously, the presence of the cover panel provides a uniform support for adjacent sealing barriers. However, this type of panel is not essential. This is because sufficient support of this type can also be obtained from the load bearing element alone. Advantageously, the presence of the base panel provides a fully distributed transmission of compressive force from the primary insulation barrier to the secondary insulation barrier or a fully distributed transmission of compression force from the secondary insulation barrier to the hull. I will provide a. However, this type of panel is not essential. This is because this transmission can also be fully assured by the load carrying element alone. This type of panel can be formed in several ways. As mentioned, one possibility is to form a load bearing structure that incorporates panels with load bearing elements as a single piece.

  In such a case, according to a particular embodiment of the non-conductive element, the non-conductive element is formed separately from the load carrying structure and the first of the load carrying element. A second panel fixed to the opposite end of the panel to form the connecting means.

  Any securing means can be used for this purpose. Advantageously, the inner surface of the second panel has recesses that are arranged in such a way as to interact with the load-carrying element by co-planar mounting.

  Preferably, in such a case, the second panel has a coefficient of thermal expansion that is different from the coefficient of thermal expansion of the load bearing element, so that when the tank is cooled, the second panel And the load bearing element mounted flush with the latter.

  According to a further embodiment of the non-conductive element, this non-conductive element has two load-carrying structures, the load-carrying structures having their respective panel inner surfaces towards each other. Load-bearing elements that are arranged in a bendable manner and project from these inner surfaces are in each case opposed to the panels at their ends in order to form the load-bearing elements of the non-conductive elements Are assembled in pairs. In other words, in such a case, each load-bearing element of the two load-bearing structures is in each case a load having two parts extending through a portion of the thickness of the non-conductive element, respectively. For the purpose of forming the holding element, it is arranged end to end. In particular, it is possible to use two completely symmetrical load bearing structures.

  Advantageously, a piece of thermal insulation having a thermal conductivity lower than that of the load carrying element is in each case interposed between the two assembled load carrying elements. This makes it possible to improve the insulation provided by the nonconductive element.

  These two load bearing structures can be assembled by any means. Preferably, the load-carrying elements of these two load-carrying structures are assembled in pairs in each case by connecting pieces having a coefficient of thermal expansion different from that of the load-carrying element. When the tank is cooled, a grip is produced between the connecting piece and the load carrying element. As a modified embodiment or in combination, the connecting pieces can also be fixed in the same plane, joined together by adhesive, snap-fit, or otherwise.

  Preferably, the load bearing structure of the non-conductive element is manufactured using a molding, extrusion, pultrusion, thermoforming, blow molding, injection molding, or rotational molding process. These load bearing structures can be made from any material suitable for the processes described above, in particular plastics such as PC, PBT, PA, PVC, PE, PS, PU and other resins. Advantageously, these load bearing structures are manufactured from composite materials. The use of this type of material together provides the necessary conditions to obtain a load bearing element with a thinner wall thickness using plywood, while at the same time providing a barrier or equivalent thermal conductivity and a lower coefficient of expansion. For example, these load bearing structures can be made from a composite material based on a polymer resin (eg, a polyester resin or another resin). Within the meaning of the present invention, composite materials based on polymer resins include all types of fillers, additives, reinforcements or fibers (eg glass) that provide sufficient breaking strength and stiffness as well as other properties. Fibers or other fibers), or polymers or mixtures of polymers. Additives can also be used to reduce the density of the material and / or to improve the thermal properties of the material, in particular to reduce its thermal conductivity and / or its expansion coefficient. Composite materials containing a high percentage of sawdust including synthetic binders can also be utilized. In certain embodiments, the load bearing structure can also be made from laminated wood or plywood molded by hot compression.

  According to a particular embodiment, the at least one thermal barrier comprising the nonconductive element is covered by one of the hermetic barriers, which in each case is formed from a thin sheet metal strip. The sheet metal strip has a low coefficient of thermal expansion, and the edge of the sheet metal strip bulges towards the outside of the non-conductive element, the non-conductive element being A cover panel having parallel grooves spaced apart by a width of which a welding support is slidably held, each welding support pair projecting from the outer surface of the cover panel The raised edges of two adjacent strips are welded in a leak-proof manner on the two sides of the weld support. These sliding weld supports form a sliding joint and allow different barriers to move relative to each other through the effects of thermal shrinkage differences and the movement of liquid contained in the tank. .

  Advantageously, the parallel grooves are provided in longitudinal ribs protruding from the cover panel. This embodiment makes it possible to reduce the thickness of the cover panel between these ribs. Advantageously, a layer of insulating foam is provided on these cover panels between these longitudinal ribs in order to support a sealing barrier covering the hollow element.

  Advantageously, a secondary retaining member, integral with the ship's load-bearing structure, secures the non-conductive element forming the secondary insulation barrier to the load-bearing structure and this secondary sealing. A primary retaining member coupled to the weld support of the barrier holds the primary insulation barrier against the secondary sealing barrier, and the weld support supports the secondary sealing barrier of the secondary insulation barrier. Hold against the cover panel of the non-conductive element. Therefore, the primary insulation barrier is fixed on the secondary insulation barrier and does not affect the conductivity of the secondary sealing barrier interposed therebetween.

According to a preferred embodiment, the insulating liner is reinforced or unreinforced, rigid or flexible, low density (ie less than 60 kg / m ³ , eg approximately 40-50 kb / m ³ ) The foam is provided. This foam has good thermal properties. It is also possible to use nanoscale porous airgel type materials. This airgel-type material is a low density solid material that is extremely fine and has a very porous structure (possibly with a porosity of up to 99%). The pore size of these materials is typically in the range between 10 nm and 20 nm. The nanoscale structure of these materials greatly limits the gas molecules, and thus also the mean free path of convective heat and mass transfer. Therefore, airgel is a very good thermal insulator, for example, less than 20 × 10 ⁻³ W · m ⁻¹ · K ⁻¹ , preferably less than 16 × 10 ⁻³ W · m ⁻¹ · K ^−1. It has a thermal conductivity of These typically have a thermal conductivity that is 2 to 4 times lower than the thermal conductivity of other conventional insulation (eg, foam). The airgel can be in different forms, for example in the form of powders, beads, non-woven fibers, fabrics and the like. The very good insulating properties of these materials make it possible to reduce the thickness of the insulating barrier in which they are used, thereby increasing the effective volume of the tank.

  The present invention also provides a floating structure (especially a methane carrier), characterized in that it comprises a sealed insulated tank according to the subject matter of the invention. This type of tank is particularly suitable for FPSO (floating type manufacturing, storage and unloading) equipment (used to store liquefied gas for the purpose of exporting liquefied gas from the manufacturing site) or FSRU (floating type storage And regasification units) (used to unload methane carriers for the purpose of supplying gas transport systems).

  In the following description of specific embodiments of the invention, the present invention will be better understood and further objects, details, features and advantages of the present invention will become more apparent. The following description of specific embodiments of the invention is provided only by way of non-limiting exemplary examples with reference to the accompanying drawings.

  The present invention provides a tank that improves at least one of the following features without damaging the others of the following features: cost price of the tank, ability of the wall to withstand pressure, and thermal insulation of the wall . The present invention further provides a non-conductive element that is easy to manufacture and improves the ability of the wall to withstand pressure, and without impairing the insulation of the wall, and if possible, simultaneously improving these characteristics. Tanks are provided.

  A description of several embodiments of a sealed, insulated tank that is incorporated and secured in a dual hull of a FPSO or FSRU or methane type carrier structure is given below. The general structure of such a tank is known per se and has a polygonal shape. Accordingly, only a description of the tank wall zone is given and it is understood that all walls of the tank have a similar structure.

  A description of general embodiments useful for understanding the invention will now be given with reference to FIGS. FIG. 1 shows a double hull zone (represented by 1) of a ship. The tank wall, in order in its thickness, is a secondary insulation barrier 2 (formed from a caisson 3 juxtaposed on the double hull 1 and secured to the caisson by a secondary holding member 4), then Secondary sealing barrier 5 (held by caisson 3), then primary insulation barrier 6 (formed from parallel caisson 7 secured to secondary sealing barrier 5 by primary holding means 48), and finally, It consists of a primary sealing barrier 8 (held by caisson 7).

  The caissons 3 and 7 are parallelepiped non-conductive elements, have the same structure or different structures, and have the same or different dimensions.

  The secondary holding members 4 are fixed on the pins 31 welded to the double hull 1 in a regular rectangular grid arrangement, so that these holding members 4 are in each case four caissons 3. The corners of these caissons meet. Two secondary retaining members 4 are also provided in the central zone of each caisson 3.

  The secondary sealing barrier 5 is manufactured in the form of a membrane consisting of Invar plate filaments 40 with raised edges according to known techniques. As can be seen better in FIG. 3, the cover panel 11 of the caisson 3 has a longitudinal groove (represented by 41) having an inverted T-shaped cross section. A welding support 42 in the form of invar cleaning, folded in an L shape, is slidably inserted into each groove 41. As can be seen in FIGS. 2 and 3, each sheet wire strip 40 extends between two weld supports 42 and is in each case continuously welded to the corresponding weld support 42 by weld beads 44. In addition, it has two raised edges 43.

  Similarly, the caisson 7 of the primary insulation barrier is fixed in each case at the four corners of the caisson 7 and at two points in the central zone of the caisson 7. For this purpose, in each case the primary holding member 48 shown in detail in FIGS. 2 and 3 is used. The primary retaining member 48 has a lower sleeve 49 that is integral with the lug 50, which lugs at several (eg, three) portions 51 of the weld support 42, the raised edges of the sheet wire 40. 43 is welded above. A rod 52 made from Permali (a composite material based on a beech material impregnated with resin) has a lower end fixed in the lower sleeve 49 and an upper end fixed in a sleeve 54 integral with the support washer 53. The support washer presses the cover panel 11 of the caisson 7 and is accommodated in the counter sink 28 at the corner of the caisson 7 and the central shaft 30. The sleeve 54 is threaded and is threaded onto the corresponding threaded end of the bar 52. When the washer 53 is positioned in this way, a fixing screw 56 is engaged through a hole 55 provided in the washer 53 and screwed into the panel 11 for the purpose of preventing any subsequent rotation of the washer 53. In each thermal barrier, caissons 3 and 7 are juxtaposed with a small intermediate spacing of approximately 5 mm.

  Advantageously, a layer of airgel-type material with nanoscale pores (which is a very good insulation) is included as an insulation liner in caisson 3 and / or 7. Airgel also has the advantage of being hydrophobic so that moisture absorption from the boat to the thermal barrier is prevented. The thermal insulation layer can be made of airgel, possibly pocketed, in the form of a fabric, or in the form of beads.

Generally speaking, aerogels can be made from a number of materials, including silica, alumina, hafnium carbide and also various polymers. Further, according to the manufacturing process, the airgel can be manufactured in the form of powders, beads, monolithic sheets and reinforced flexible fabrics. Aerogels are generally manufactured by extracting or replacing the liquid of a gel with a micron-sized structure. This gel is typically produced by chemical conversion and reaction of one or more dilute precursors. As a result, a gel structure in which a solvent is present is generated. In general, a supercritical fluid such as CO ₂ or alcohol is utilized to replace the gel solvent. The properties of the airgel can be modified by using various doping agents and toughening agents.

  The use of airgel as an insulating liner significantly reduces the thickness of the primary and secondary insulation barriers. For example, in caisson 3 and 7, it is possible to consider a barrier 2 having a thickness of 200 mm and a barrier 6 having a thickness of 100 mm by using an airgel bed in the form of a fabric. Thereby, the wall of the tank has a total thickness of 310 mm. As a modified embodiment, in each case caisson 3 and 7 it is possible to envisage a tank wall having a total thickness of 400 mm by using a layer of airgel particles (in particular airgel beads).

  With reference to FIGS. 4 and 5, a description of a first embodiment of a sealed insulated tank according to the present invention will now be given. In the first embodiment, the primary and secondary insulation barriers are formed from a unit block contour caisson 70 filled with an insulation liner instead of the caisson 3 and 7 described above. This type of caisson 70 is shown in perspective view in FIG. This is obtained by extrusion of a polymer resin and fiber based composite (eg polyester or epoxy resin reinforced with glass or carbon fibers). To accomplish this, the material is processed as follows: First, the fibers are impregnated with resin in a static or pressurized bath. These fibers are then passed through a die. The role of this die is to provide the corresponding contoured section geometry. At the same time, polymerization occurs. The resulting product is continuous and cut to the appropriate dimensions. This is therefore a mass production process, including from one end to the other, fibers and resins, dies, and finished products that are cut to the appropriate size.

  The caisson 70 has a contoured section shape with a constant cross-section and has a base panel 71 and a cover panel 72. The base panel 71 and the cover panel 72 are parallel and rectangular, and there is a long axial section 75 between the panels, which section includes a plurality of longitudinal cells 73. Stipulate. These cells have a generally rectangular cross-section and also have two end cells 74 in the area of the two sides of the caisson 70. The longitudinal section 75 is thicker in the region of the end zone 68 that is connected to the base panel 71 and the cover panel 72. Cells 73 and 74 are adapted to receive insulation liner 76 (eg, phenolic foam, low density polyurethane foam (possibly fiber reinforced), and / or insulation based on one or more layers of airgel). To work.

  In the example shown in FIG. 5, the thickness of the base panel 71 is 6 mm, the thickness of the cover panel 72 is 9 mm, and the thickness of the longitudinal section 75 is 6 mm in each case. . The number of longitudinal sections 75 is merely exemplary and can be modified as desired.

  The base panel 71 has longitudinal cuts 71 in the area of the two cells 73, which in each case span the entire thickness and length of the panel 71. These notches 77 serve to pass the holding member of the caisson 70. Above the two notches 7 in the vertical direction, the cover panel 72 has two longitudinal grooves 78 and has an inverted T-shaped cross section. The groove 78 has the same function as the groove 41 of the first embodiment. A weld support 42 is slidably inserted into each groove 78 in the form of an Invar filament folded in an L-shape.

  The caissons 70 of the secondary insulation barrier 2 and the primary insulation barrier 6 are fixed at four points in each case. To achieve this, the cover panel 72 has in each case holes 80 which are surrounded by a counter sinking 81 and also vertically above the two notches of the base panel 71. Be placed.

  The manufacture of the tank wall according to this first embodiment will now be described with reference to FIGS. The caissons 70 forming the secondary insulation barrier 2 are fixed to the double hull 1 by four pins 82 in each case. These pins are welded to the double hull 1 and are placed opposite the holes 80, and in each case, a washer 83 is placed that presses against the base panel 71 and a nut 84 is engaged. Combined. A shim is provided around the threaded pin 82 because the geometry of the double hull 1 is irregular. The thickness of each shim is calculated by the computer based on the topographical survey of the inner surface of the double hull 1. Accordingly, the base panel 71 is positioned along a theoretical regular surface. Conventionally, polymerizable resin beads (not shown) are provided between the base panel 71 and the double hull 1, these beads are adhesively bonded to the base panel 71 and the caisson 70 is attached. In some cases, they are crushed against double hulls, thereby providing support for these hulls. To avoid this resin sticking to the double hull, a sheet of kraft paper (not shown) is provided between them.

  A cylindrical shaft 85 is provided in the thermal insulation liner 76 so that these operations can be performed from the top of the caisson 70 and the shaft is subsequently filled with thermal insulation.

  In an alternative embodiment, the washer 83 can also be arranged to compress the cover panel 72 rather than the base panel 71. To accomplish this, a washer 83 is attached to the top of an elongate coupling member (eg, a member similar to member 48) that is inserted through a shaft 85 and the base of this member is, for example, , Secured to the pin 82 by a threaded sleeve.

  The sealing barriers 5 and 8 are manufactured in the same way as in the general embodiment by the invar plate filament 40 welded to the weld support 42 housed in the groove 78 of the caisson 70. The secondary sealing barrier weld support 42 engages through a longitudinal notch 77 in the caisson 70 to form the primary thermal barrier 6. The caisson 70 forming the primary insulation barrier 6 is secured with the aid of the primary holding member 48, the same as described in the general embodiment. In each case, the compression washer 53 is accommodated in the bottom of the counter sinking 81.

  In these two thermal barriers, the caisson 70 is juxtaposed edge to edge with minimal clearance, allowing alignment errors to be compensated.

  Providing the hole 80 vertically above the notch 77 ensures that the retaining member 48 operates properly in the axial direction when coupled to the underlying weld support 42. This also makes it possible to create two insulating barriers using exactly the same Uno caisson, which simplifies their manufacture. However, in the secondary insulation barrier caisson, the notch 77 can be replaced by a cylindrical hole.

  The hole 80 can also be offset relative to the groove 78 in each of the thermal barriers.

  With reference to FIG. 7, a description is now given of a tank wall in which the primary insulation barrier 6 and the secondary insulation barrier 2 are respectively formed from caissons 170a, 170b according to further embodiments. In caisson 170a and 170b, elements that are the same or similar to elements of caisson 70 have the same reference numbers increased by 100 and are not described unless they differ from elements of caisson 70. Four caissons in a useful position are shown in FIG.

  An important feature of the caissons 170a and 170b is that they have oblique longitudinal sections 192 and 193 (ie, sections that are not perpendicular to the base panel 171 and the cover panel 172). In the example shown, each compartment comprises a compartment 192 that is inclined approximately 30-50 ° in one direction, and the compartment 193 is inclined approximately 30-50 ° in the opposite direction. These compartments are provided in the longitudinal cell 173 adjacent to the end cell 172 in each case for the purpose of dividing the end cell into two triangular cross-section cells. However, other configurations are possible in terms of the number, position, and slope of the sloped sections. This type of compartment not only absorbs the shared force, but also absorbs the clamping and tilting forces applied to the caisson.

  On caisson 170a and 170b, a groove 178 designed to receive weld support 42 extends in the width direction (ie, perpendicular to longitudinal section 175). Accordingly, the base panels 171 of the caissons 170a and 170b do not have a longitudinal notch.

  In the caisson 170a, a notch 177 for passing through the weld support 42 spans the entire width of the caisson and intersects the longitudinal section 175. Furthermore, these notches 177 are offset with respect to the groove 178. Accordingly, the coupling member 48 that holds the barrier 6 presses against the cover panel 172 in the area surrounding the hole 180 of the counter sinking 181, and these holes are offset with respect to the groove 178. In FIG. 7, nine coupling members 48 that are present at regular intervals are provided per caisson 170a. However, depending on the size of the caisson, more than 9 or less than 9 fixed points (eg, 4 or 6) per caisson 170a and 170b may be sufficient.

  The caisson 170b forming the second thermal barrier 2 is fixed to the double hull 1 by four pins 82 in each case. These pins are welded to the double hull 1 and in each case engage with corresponding holes in the base panel 171. Aligned vertically with these holes (not shown) is a cylindrical passage with holes 191 through the diagonal sections 192 or 193 and holes 190 through the cover panel 172. These holes allow a box wrench to be inserted to tighten the nut 84. Alternatively, it may be provided that the coupling members cross these holes for the purpose of coupling the pin 82 to the cover panel 172, rather than securing the caisson 170b in the region of its base panel 171.

  The caissons 70 and 170a-b are self-supporting caisson capable of withstanding the pressure of the liquid in the tank, so that the sealing barriers 5 and 8 supported by these caissons are themselves at this pressure. Is advantageously produced in the form of a very thin member of Invar, for example having a thickness of 0.7 mm.

  FIG. 8 shows a cross section of a non-conductive caisson 270 (also having a contoured load bearing structure). The load carrying structure has an inverted U-shaped cross section, and the cover panel 272 and the two load carrying compartments 275 are substantially perpendicular to the structure. This structure may be manufactured using the previously shown process or by plastic molding. According to a further possibility, this U-shaped cross section can be obtained by forming a laminated wood or plywood panel. Insulation 276 (eg, a low density plastic foam) fills the space between compartments 275 and adheres to the contoured load bearing structure.

  FIG. 10 shows a non-conductive caisson 470 whose cross section has a comb shape and each of the cover panel 472 and the vertical load-carrying section 475 is enlarged in the region of connection with the panel 472. Part 468. Insulation 476 fills the longitudinal cells formed between compartments 475. This comb structure can be extruded or molded as a single piece. Another possibility is to fix a plurality of caissons having the shape of the caisson 270 side by side, for example by gluing or stapling together.

  Caisson 270 or 470 may be used in place of caisson 170a or 170b in FIG. In such a case, the primary caisson rests on the second sealing barrier 5 via the end of the compartment 275 or 475. The secondary caisson rides on the resin strip described above in the same manner. To prevent pinching of the barrier 5 or resin strip, a single flat plate can be provided that extends at the end of each compartment 275 or 475. Base panel (not shown) secured to the underside of the caisson 270 or 470 by, for example, adhesive bonding, stapling and / or flush mounting at the end of the compartment 275 or 475 at the panel thickness Can also be provided. When such a single panel or a separate panel is added, the caisson 270/470 is clearly in the opposite position (ie, the panel 272/472 as the base panel and a single plate or separate panel As a cover panel) and can be used with the groove holding the weld support of the adjacent sealing barrier.

  FIG. 9 shows that the contoured load bearing structure has a bullet-shaped cross section, each of the alternating cover panels 372 and base panels 371 extending over a portion of the caisson width, and in each case the load bearing structure. A non-conductive caisson 370 connected by compartments 375 is shown. A layer of insulation is formed by thick foam plates 376a and 376b in the longitudinal direction, which in each case are bonded below the panel 372 between two compartments 375 on the panel 371. Is done. The caisson 370 can be used as shown or can be used with an auxiliary cover panel and / or base panel secured to the caisson. Other contoured load bearing structure sections can also be manufactured, for example, in an H-shaped or I-shaped shape.

  With reference to FIGS. 11-15, a description of a further embodiment of a non-conductive caisson or element that can be used to form a thermal barrier on the walls of a tank is given, the general structure of which is shown in FIGS. As described with respect to FIG. The manufacture of the sealing barrier and the attachment of the various barriers is similar to the previous embodiment, and there is nothing that will be described here again.

  FIG. 12 shows caisson 570 and caisson 670 in an enlarged perspective view, each of which is manufactured with the aid of a molded load bearing structure 500, the description of which is now referred to FIG. Given.

  The load bearing structure 500 is an injection molded piece made from any suitable material. This structure has a flat plate 571 with chamfered corners. For example, a square or rectangular shape with a side of 1.5 m, and 16 hollow cylindrical columns 575 project from one surface and are arranged in a regular square lattice shape. There are two tubes 581 of smaller cross section in the area of the central zone of the plate and also four triangular columns 580 in the area of the four corners of the plate. The plate 571 is continuous in the region of the base of the columns 575 and 580, but is perforated in the region of the base of the tube 581 for the purpose of allowing the coupling rod to pass through. Furthermore, in the case of the caisson of the primary barrier 6, the plate 571 is slit for the purpose of allowing the passage of the welded support 42 and the raised edge 43 of the plate line of the secondary sealing barrier. The pillars 580 serve to receive the holding force of the coupling member used at each corner of the non-conductive element. The cross section of the column 575 is, for example, 300 mm for a 1.5 square meter plate. As with the insulating liner, the load bearing structure 500 can be covered with a layer of low density foam, which is poured between the posts 575.

  The cross section of these pillars can be quite large and what is important is to always provide several pillars per caisson. Thus, the column dimensions in terms of cross-section can be 1/3, or even 1/2 of the corresponding diameter of the caisson.

  For the purpose of forming the caisson 570, an independent panel 572 having the same dimensions as the plate 571 is secured to the end of the column 575 on the opposite side of the plate. The panel can be secured by any means (adhesive bonding, stapling, flush mounting, etc.). In FIG. 12, a circular groove 573 is provided on the inner surface of the panel 572 to securely receive the end of each column 575.

  The material of structure 500 and panel 572 can be selected to cause thermal shrinkage of pillars 575 in the panel. For example, using a panel 572 made from a PVC-made part 500 and plywood (which exhibits lower thermal shrinkage), the ends of the pillars 575 are notched by grooves 573 when the tank is cooled. It is intended to grip a defined circular core. Conversely, gripping of the pillars 575 can also be obtained using a panel 572 that makes better contact with the part 500.

  The panel 572 has a hole 574 that faces the tube 581 of the molded structure 500.

  In the caisson 670, two identical molded structures 500 are arranged symmetrically and assembled together by pressing their respective posts 575 together. The assembly can be manufactured by any means (adhesive bonding, welding, flush mounting, etc.). In FIG. 12, this is achieved in each case by a connecting ring 680 interposed between two aligned posts 575 and mounted flush on them. This assembly can be seen better in FIG. 13, in which it is observed that the coupling ring 680 has an outer ring 682 and an inner ring 681 connected by a radial tongue 683. A column 575 is mounted flush between these two rings 681 and 682 and abuts either surface of the tongue 683. The material of the ring 680 can be selected to have a lower conductivity than the column 575 for the purpose of performing a thermal insulation function. These materials may alternatively or in combination be selected to have a different coefficient of expansion than column 575 for the purpose of performing a thermal assembly function. In an alternative embodiment, two molded structures having columns with complementary ridges can be secured together by nesting these columns directly together.

  The foam filled part 500 can also be used alone without an auxiliary panel by rotating the plate 571 toward the inside of the tank for the purpose of supporting the adjacent sealing barrier. The non-conductive element thus formed rests on a post 575 on the secondary sealing barrier or on a strip of resin fixed to the hull.

  FIGS. 14 and 15 show shaped load bearing structures 600 and 700 that allow non-conductive elements to be manufactured in a manner similar to the structure 500 described above.

  14, the same reference numerals as in FIG. 11 represent the same elements. The structure 600 comprises a flat peripheral wall 601 that extends continuously along the four edges of the plate 571 to form a box that can accommodate insulation in the form of powder, beads, and the like. . For example, the structure 600 containing airgel beads may be combined with the structure 600 containing low density foam to form a caisson 670 as shown in FIG.

  In FIG. 15, the flat plate 771 has 36 hollow sections with a smaller cross-sectional area (e.g., 100 mm) than the column 575 described above in order to allow the coupling member to serve to attach the thermal insulation member through. Tubular column 775, four hollow tubular columns 780 having a smaller cross-sectional area (eg 50-60 mm) at the corners, and two tubular columns similar to column 780 in the central zone region of plate 771. A column 781 is included.

  The structures 500, 600 and 700 can be injection molded. Similar structures can also be obtained by thermoforming from plastic plates. This possibility is illustrated in FIG. 11A. In such a case, the flat plate 571 is first heated and deformed to match the stamp on the female mold 560. This creates a load bearing column 575 in which the side edges of the plate are open and the opposite end is closed by a wall 583. In such a case, the space 582 located inside the pillar 575 is filled with, for example, foam, from the surface of the plate 571 opposite to these pillars.

  The wall 601 can also be obtained by thermoforming.

  FIG. 24 is a perspective view of a thermoformed load bearing structure 1300 comprising a plate 1371 that can serve as a base or cover panel for the caisson and a load bearing column 1375 obtained in a manner similar to column 575 of FIG. 11A. Shown in the figure. In the example shown, the post 1375 has a truncated cone shape that facilitates the formation of the post. For example, column diameters can be provided that vary from 160 mm at the base to 120 mm at the top over a height of approximately 100 mm.

  For the purpose of serving as the base panel of the caisson of the primary thermal barrier, the plate 1371 includes two longitudinal ribs 1384 that extend the entire length of the plate 1371. Each rib 1384 is obtained during a thermoforming operation by pushing the material in the same direction as the column 1375, thereby forming a V-shaped fold. This fold is open on the flat surface of the plate 1371, and the internal space 1385 of this plate allows the welded support 42 and the raised edge 43 of the secondary sealing barrier to pass through. In the case of a secondary thermal barrier, the rib 1384 is unnecessary.

  A description of a load carrying structure comprising a plate that serves as a cover panel or base panel was given earlier. Referring now to FIG. 16, a description of a further embodiment of a non-conductive element 870 with a load carrying element 875 having a small cross-section, where the shaped load carrying structure 800 is connected by an arm 890 is given. It is done. This load holding structure is shown in plan view in FIG. The load bearing elements 875 are hollow cylindrical columns, arranged in a regular grid and connected by arms 890 arranged in the form of a square mesh grid. Cover panel 872 and base panel 871 (e.g., made of plywood, plastic, composite material, or other material) are bonded together on two surfaces opposite load bearing structure 800. The arm 890 is positioned adjacent to the panel 872 at the end of the load bearing element 875 and has a flat upper surface that can serve for bonding of the panel 872 by adhesion.

  FIG. 25 shows the non-conductive element 870 in an enlarged perspective view with a slightly modified version in terms of the placement of the connecting arm 890.

  Another arm may be provided in the region of the lower end of the column 875. These arms can also be placed in another area of the load bearing column (eg, half above).

  The interior space of the caisson 870 (ie, the interior space 880 of the pillars 875 and the space 876 between the pillars) is filled with one or more types of insulation. When low density foam is used, the caisson places a structure 800 with a rectangular shape in plan view into the mold and pours the foam into the mold, thereby making the structure 800 parallel to the foam. It can be manufactured by embedding in a hexahedral block and then fixing the panels 872 and 871 to this block. The base panel 871 is not always necessary. One of these panels can also be molded as a single piece with the structure 800.

  Given the description of the circular cross-section hollow load-bearing columns in the load-bearing structures 500, 600, 700 and 800, these load-bearing columns can have any other shape in terms of cross-section, And it can have any type of regular or irregular spatial distribution. For example, FIG. 18 shows a load carrying column 975 that is comprised of a plurality of concentric cylindrical walls 976. In the column 1075 of FIG. 19, the cylindrical wall 1076 has a square cross section. These columns may also have a cross section that varies across their height (eg, frustoconical columns).

  FIG. 20 shows pillars 1175 distributed in a line in a regular figure shape and having a hollow square cross section with chamfered corners. In FIG. 21, pillars 1275 are, for example, solid cylindrical shapes and distributed in an alternating arrangement. Other cross sections (ie, rectangular, polygonal, I-shaped, solid or hollow, bipyramid, etc.) can also be achieved.

  In all cases, such posts are shaped to protrude from the plates and / or connected by arms and / or by any connecting means formed as a single piece with these posts. obtain. If a low density foam is utilized as the insulating liner layer, it is particularly possible to pour the foam in a single step across the entire surface area of the connecting plate, between the load bearing columns and possibly inside these columns. It is advantageous. Another possibility is to machine the wells into previously formed foam blocks and insert load bearing elements into these wells formed for this purpose.

  In the case of granular insulation, it is necessary to use a non-conductive element with a surrounding wall, preferably formed as a single piece with the load bearing structure, as shown in FIG. Thanks to the shape of the load-carrying elements with a small cross-sectional area, the internal space of the box between these elements is not divided into compartments, so the granular material is more easily distributed over the entire surface area of this non-conductive element Is done. The granular material can also be inserted into a hollow column.

  Load bearing columns with very small cross-sectional areas (eg, less than 40 mm) can be left empty without compromising thermal insulation. Small cross-section hollow columns can also be filled with flexible PE foam or glass wool.

  22 and 23, a description of an embodiment of a non-conductive element comprising a single block hollow caisson 1470 manufactured by rotational molding or injection blow molding will now be given. The caisson has the shape of a closed hollow envelope 1477 with eight frustoconical columns 1475 that are formed to project from the base wall 1471 of the envelope and each column is There are top walls 1483 that can compress the top wall 1472 of this envelope in order to absorb compressive forces.

  Six frustoconical shafts 1480 are provided that are placed around the envelope and open through the top wall 1472 to secure the caisson. Each of these shafts has a base wall that can compress the base wall 1471 for the purpose of absorbing compressive forces and can be perforated for the purpose of receiving a fixation rod, which is shown schematically at 1431. This is, for example, a pin welded to the hull or a coupling device fixed to the underlying sealing barrier.

  The interior space 1476 of the caisson and the interior space 1482 of the pillar 1475 can be filled with any suitable thermal insulation, for example by foam injection.

  Similarly, the shaft 1480 can be filled with thermal insulation (eg, PE foam or glass wool) after the caisson is secured.

  For example, high density PE, polycarbonate, PBT or another plastic may be utilized to mold the caisson 1470. The shaft 1480 also utilizes another method for attaching the caisson (eg, a coupling member that passes between the caissons to be attached and compresses the top wall 1472 in the manner of the retaining member 48 of FIGS. 2 and 3). Can be distributed. The base panel and / or cover panel may also be secured to the envelope wall for the purpose of reinforcing the envelope.

  In the load bearing structures 500, 600, 700, 800, 1300, and 1470, the pillars can also be replaced with dividers that create compartments within the load bearing structure.

  An explanation of an essentially parallelepiped, right angle non-conductive element was given, but other shapes of cross-sections are possible, in particular any polygonal shape capable of separating flat surfaces. Is possible.

  Of course, the insulation layer of the non-conductive element may comprise multiple layers of material.

  If one of the primary insulation barrier and the secondary insulation barrier is produced with the aid of the non-conductive element, the other insulation barrier can be produced in the same manner, but not necessarily. . Two different types of non-conductive elements can be used in these two barriers. One of these barriers may consist of prior art non-conductive elements.

  The secondary insulation barrier and the primary insulation barrier caisson may be secured to the hull of the ship in a different manner than the example shown in the figure (eg, with the aid of a retaining member that engages the base panel of the caisson).

  In a known manner, the connection of the corners of the primary and secondary barriers in the zone where the walls of the load bearing structure meet at an angle can be achieved in the form of a connecting ring. The structure of this ring remains substantially constant along the entire intersecting ridge of the walls of the load bearing structure. The structure of such a connection ring is well known and will not be described in detail herein. In the case of tanks incorporated in a ship, this type of ring is generally arranged along the angle formed between the longitudinal wall of the ship's double hull and a partition extending across the ship. The

  Within the meaning of the present invention, “tank walls” include corner connection zones (especially connection rings) where the non-conductive elements can also be used and are independent of the shape of these zones.

  Although the invention has been described with reference to a number of specific embodiments, the invention is clearly not limited to these embodiments in any manner and all technical equivalents of the described means, In addition, combinations of these equivalents are also included within the scope of the present invention.

FIG. 1 is a cut-away rear perspective view of a tank wall, according to a general embodiment, useful for understanding the present invention. FIG. 2 shows a primary holding member of the tank wall of FIG. 3 shows the primary retaining member of the tank wall of FIG. 1 as viewed in a direction perpendicular to FIG. FIG. 4 is a cross-sectional view of a tank wall according to one embodiment of the present invention. FIG. 5 is a partial perspective view of the insulated caisson of the tank wall shown in FIG. FIG. 6 is an enlarged view of the zone XV of FIG. FIG. 7 is a cutaway rear perspective view of a tank wall zone according to another embodiment of the present invention. FIG. 8 shows a cross-section of a further embodiment of a non-conductive element having a load bearing structure in the form of a hollow profile section. FIG. 9 shows a cross section of a further embodiment of a non-conductive element having a load bearing structure in the form of a hollow profile section. FIG. 10 shows a cross-section of a further embodiment of a non-conductive element having a load bearing structure in the form of a hollow profile section. FIG. 11 shows a perspective view of a load holding structure formed as a single piece. FIG. 11A is a partial cross-sectional view showing a modified embodiment of the load carrying structure of FIG. FIG. 12 is an enlarged perspective view of two types of non-conductive elements manufactured with the aid of the load bearing structure of FIG. 13 is a partial cross-sectional view showing the assembly of the non-conductive element of FIG. FIG. 14 is a view similar to FIG. 11 showing another modified embodiment of the load bearing structure. FIG. 15 is a view similar to FIG. 11 showing another modified embodiment of the load bearing structure. FIG. 16 is a partial cross-sectional view of a non-conductive element according to a further embodiment of the present invention. 17 is a plan view of the load carrying structure of the non-conductive element of FIG. FIG. 18 shows a further embodiment of a load-carrying element in the form of a pillar, viewed in cross section. FIG. 19 shows a further embodiment of a load-carrying element in the form of a pillar, viewed in cross section. FIG. 20 shows a further embodiment of a load-carrying element in the form of a pillar, viewed in cross section. FIG. 21 shows a further embodiment of a load-carrying element in the form of a pillar, viewed in cross section. FIG. 22 shows in plan view a load carrying structure for a non-conductive element according to a further embodiment. FIG. 23 shows a load carrying structure of a non-conductive element according to a further embodiment in cross-section on line XXIII-XXIII. FIG. 24 shows a perspective view of a load holding structure thermoformed from a single piece. FIG. 25 is an enlarged perspective view of a non-conductive element according to a further embodiment, with the insulating liner omitted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Load holding structure 2 Secondary insulation barrier 5 Secondary sealing barrier 6 Primary insulation barrier 8 Primary sealing barrier 76 Thermal insulation liner 75 Load holding element

Claims (19)

  A sealed thermal insulation tank comprising at least one tank wall fixed to the hull (1) of a floating structure, the tank wall being continuous in the direction of thickness from the inside to the outside of the tank A primary sealing barrier (8), a primary insulating barrier (6), a secondary sealing barrier (5), and a secondary insulating barrier (2), wherein at least one of the insulating barriers is in parallel Insulating liners (76, 276, 376a-b, 476) consisting essentially of conductive elements (3, 7), each non-conductive element being arranged in the form of a layer parallel to the tank wall. ), And load-carrying elements (75, 175, 192, 193, 275, 375, 475, 575, 775, 875, 975, 1075, 1175, raised over the thickness of the insulating liner to absorb compressive forces 1275, 375, 1475), wherein the thermal insulation tank comprises at least one load carrying structure (70, 170a, 170b, 270, 370, 470, 500, wherein the load carrying element of the non-conductive element is formed from a single piece. 600, 700, 800, 1300, 1477), the single piece being in each case a connecting means (71, 72, 171, 172, 272, 371, 372, 472, 571, 771, 890, 1371, 1471), the coupling means firmly connecting the load bearing elements together at least at the highest part of the load bearing elements and the at least one load bearing structure (70) of the non-conductive element. , 170a-b, 270, 370, 470), characterized by having the shape of a hollow contour section having a constant cross section in the longitudinal direction. It sealed insulated tank.   The connecting means of the load carrying structure comprises a panel (71, 72, 171, 172, 272, 371, 372, 472, 571, 771, 1371, 1471), the panel of the non-conductive element The sealed thermal insulation tank according to claim 1, characterized in that, on the side, it extends parallel to the tank wall and the load carrying element projects from the inner surface of the panel.   The load carrying element of the load carrying structure comprises at least two longitudinal sections (75, 175, 192, 193, 275, 375, 475), the longitudinal sections being at least one of a constant cross-section relative to each other. 1 or 2, characterized in that it is arranged at a distance from each other so as to define two cells (73, 173) and is capable of receiving said insulating liners (76, 276, 376a-b, 475). Sealed insulated tank as described.   The sealed insulated tank according to claim 3, characterized in that the longitudinal compartment comprises at least one compartment (75, 175) substantially perpendicular to the tank wall.   A sealed insulation tank according to claim 3 or 4, characterized in that the longitudinal section comprises at least one section (192, 193) inclined with respect to the tank wall.   Sealed insulation tank according to claim 5, characterized in that the longitudinal compartment comprises at least two compartments (192, 193) having slopes in opposite directions from each other.   The connecting means of the load carrying structure comprises at least one connecting wall (71, 72, 171, 172, 472) connecting the longitudinal sections (75, 175, 475) over its entire length, the longitudinal axis 7. Sealing according to any one of claims 3 to 6, characterized in that the directional compartment has an enlarged portion (68, 168, 468) in the region of the zones connected by the at least one connecting wall. Insulated tank.   The non-conductive element (70, 170a-b) comprises a base panel and a cover panel, and at least one of the laterally outermost longitudinal sections of the non-conductive element has an open side 8. Any one of claims 3 to 7, characterized in that it is at a distance corresponding to at least one of the bottom panel and the cover panel from a lateral edge to define a partial cell (74, 174) A sealed heat insulation tank according to claim 1.   The non-conductive element (570) comprises a second panel (572), the second panel being formed separately from the load bearing structure (500) and forming the connecting means Tank according to claim 2, characterized in that it is fixed to the end of the load carrying element (575) on the opposite side of the first panel (571).   10. The inner surface of the second panel has a recess (573) arranged in a manner to interact with the load bearing element (575) by coplanar mounting. Sealed insulated tank.   The second panel (572) has a coefficient of thermal expansion different from that of the load carrying element (575), so that when the tank is cooled, it is mounted flush with the latter. 11. A sealed insulation tank according to claim 10, characterized in that a grip is produced between the second panel and the load carrying element.   The non-conductive element (670) has two load carrying structures (500), the load carrying structures being such that their respective panels have inner surfaces bent towards each other. The load-carrying elements (575) that are arranged at the side and project from the inner surface are in each case paired in the end region located on the opposite side of the panel to form a load-carrying element of the non-conductive element. The sealed thermal insulation tank according to claim 2, wherein the sealed thermal insulation tank is assembled.   The thermal insulation piece (680) having a thermal conductivity lower than the thermal conductivity of the load carrying element is characterized in that in each case it is interposed between two assembled load carrying elements, The sealed thermal insulation tank according to claim 12.   The load-carrying elements of the two load-carrying structures are in each case assembled in pairs by a connection piece (680), the connection piece having a heat different from the thermal expansion coefficient of the load-carrying element. 14. An expansion coefficient according to claim 12, characterized in that when the tank is cooled, a grip is produced between the connecting piece and the load carrying element (575). Sealed insulated tank.   At least one load bearing structure (70, 170a-b, 270, 370, 470, 500, 600, 700, 800, 1300, 1477) of the non-conductive element is molded, extruded, pultruded, thermoformed, 15. A sealed insulation tank according to any one of the preceding claims, characterized in that it is manufactured by a forming process selected from the group comprising blow molding, injection molding and rotational molding processes.   The at least one thermal barrier (2, 6) composed of the non-conductive elements (70, 170a-b, 870) is in each case formed from a thin sheet metal strip (40) having a low coefficient of expansion. Is covered by one of the sealed barriers (5, 8), the edge of the filament bulges towards the outside of the non-conductive element, the non-conductive element being Each having a cover panel (72, 172, 872) having parallel grooves (78, 178) spaced by the width of the strips on which the welding support (42) is slidably held. The support has continuous wings projecting from the outer surface of the cover panel, and two adjacent plate line raised edges (43) on the two sides of the weld support prevent leakage. Welded in a manner, It sealed insulated tank according to any one of 5.   A second retaining member (82-84) integral with the load carrying structure of the ship secures the non-conductive element to provide a secondary insulation barrier (2) to the load carrying structure (1). And a primary holding member (48) connected to the weld support (42) of the secondary sealing barrier (5) holds the primary insulating barrier against the secondary sealing barrier; The sealed insulated tank according to claim 16, wherein the weld support holds the secondary sealed barrier against a cover panel of the non-conductive element of the secondary insulated barrier.   A floating structure comprising the hermetically sealed heat insulation tank according to claim 1.   The floating structure according to claim 18, comprising a methane carrier.

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