Membrane containment system for bearing cryogenic liquid cargo

Abstract

A membrane containment system for bearing a cryogenic liquid cargo, comprising a primary membrane layer (5), fastening clamping plates (6), a primary insulation layer (4), a secondary membrane layer (3), and a secondary insulation layer (2) that are sequentially connected and fixed to a hull structure by means of penetrating fasteners (1). The primary membrane layer (5) is in contact with an ultra-low temperature medium; the primary insulation layer (4) comprises a plurality of primary insulation modules (14) arranged at intervals and in a matrix distributed manner, and each primary insulation module (14) located on a plane layer is of a cuboid structure; the secondary membrane layer (3) is located at the interface of the primary insulation layer (4) and the secondary insulation layer (2), and the secondary insulation layer (2) comprises a plurality of secondary insulation modules (16) arranged at intervals and in a matrix distributed manner; and spacer plates (8) and resin strips (7) are provided between the secondary insulation modules (16) and a hull steel plate. The containment system reduces heat leakage at gaps, and shortens the construction period.

Description

A membrane containment system for carrying cryogenic liquid cargo

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. 202311521212.X filed on November 14, 2023, and cites the contents disclosed in the above patent application as part of this application. Technical Field

[0003] The present disclosure relates to the technical field of equipment for transporting and storing cryogenic liquids, and in particular to a membrane-type containment system for carrying cryogenic liquid cargo. Background Art

[0004] When transporting gases like natural gas and ethane over long distances, it's common to cool the gas to low temperatures and liquefy it for more economical transport. This liquefied gas significantly reduces its volume, lowering transportation costs. The liquefied cryogenic liquid is stored and transported in specialized cryogenic cargo tanks.

[0005] In the current shipbuilding industry, cryogenic liquid cargo containment systems primarily involve the construction of LNG vessels. For LNG vessels, the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) defines four main types of containment systems: Type A, Type B, Type C, and membrane. Membrane containment systems are widely used due to their advantages, including high tank capacity utilization, excellent thermal insulation, and reduced wind resistance.

[0006] The existing membrane containment system technologies mainly include Mark III and NO 96, both of which are from the French company GTT. However, both containment systems have their own shortcomings. For the NO 96, since its main and secondary insulation modules are arranged in an overlapping manner, the gaps between the main insulation modules and the gaps between the secondary insulation modules are directly connected to the hull structure. Although insulation materials such as glass wool are evenly distributed in the gaps, there is still a large amount of heat leakage in the gaps. For the Mark III, since the main insulation modules, secondary insulation modules and secondary membranes are fixed to each other with glue and fixed to the hull structure with epoxy resin, the relative movement between the main and secondary insulation modules is restricted, and the overall resistance to hull movement and liquid cargo sloshing is poor. In addition, the large amount of glue used leads to a long construction period. Due to the strict requirements on the construction environment (humidity and temperature) and process, the delivery of the entire ship is delayed.

[0007] Summary of the Invention

[0008] In view of the above-mentioned problems existing in the prior art, an embodiment of the present disclosure provides a film-type containment system for carrying low-temperature liquid cargo, wherein the film-type containment system is used to accommodate ultra-low temperature media, and includes a main film layer, a fastening card plate, a main insulating layer, a secondary film layer and a secondary insulating layer, which are sequentially connected and fixed to the hull structure (hull steel plate) through penetrating fasteners. That is, a main insulating layer and a fastening card plate are arranged between the main film layer and the secondary film layer, and a secondary insulating layer is arranged between the secondary film layer and the hull structure. The main film layer, the fastening card plate, the main insulating layer, the secondary film layer and the secondary insulating layer are all connected and fixed to the hull structure through penetrating fasteners. At the same time, the space between the main film layer and the secondary film layer forms a main shielding space, and the space between the secondary insulating layer and the hull structure forms a secondary shielding space, effectively building a double-layer sealed ultra-low temperature medium storage carrier, solving the storage and leakage prevention problems of ultra-low temperature media.

[0009] The disclosed embodiment provides a film-type containment system for carrying cryogenic liquid cargo, the film-type containment system being used to accommodate ultra-low temperature media, comprising a main film layer, a fastening card plate, a main insulating layer, a secondary film layer and a secondary insulating layer, which are sequentially connected and fixed to a hull structure by penetrating fasteners, the main film layer, the main insulating layer, the secondary film layer and the secondary insulating layer enclosing a cryogenic liquid cargo storage tank for accommodating ultra-low temperature media, the main film layer being arranged as the innermost layer of the film-type containment system, directly contacting the ultra-low temperature media, and the main film layer being formed by welding a plurality of main films having a first preset size, wherein the main film is made of invar steel or 304L stainless steel prefabricated into a set corrugated shape, thereby enhancing the thermal deformation capacity of the main film;

[0010] In the membrane-type enclosure system, the main insulation layer includes a plurality of main insulation modules that are spaced apart and arranged in a matrix, and the first gap between two adjacent main insulation modules is filled with a flexible thermal insulation material;

[0011] The fastening card is arranged between the main film layer and the main insulating layer, and the fastening card includes at least one strip card located above the first gap and mounted on the main insulating module on both sides of the first gap;

[0012] The secondary film layer is located at the interface between the main insulating layer and the secondary insulating layer, and the secondary film in the secondary film layer is made of a flexible sealing material that meets low temperature resistance conditions;

[0013] The secondary insulation layer comprises a plurality of secondary insulation modules that are spaced apart and arranged in a matrix, and the second gaps between two adjacent secondary insulation modules are filled with flexible thermal insulation material;

[0014] The secondary insulation module is fixedly connected to the hull steel plate through its lower surface, and a distance plate and a resin strip are provided between the insulation module and the hull steel plate for flat installation of the secondary insulation module and for fixed installation between the module and the hull steel plate;

[0015] The space between the primary film layer and the secondary film layer forms a primary shielding space, and the space between the secondary insulating layer and the hull structure forms a secondary shielding space. Both the primary shielding space and the secondary shielding space are filled with inert protective gas.

[0016] In some embodiments of the present disclosure, the main insulation module in the planar layer has a rectangular structure, and each main insulation module includes a first top plate, an upper insulation block, a middle plate and a lower insulation block fixedly connected in sequence from top to bottom. The first top plate is provided with a first through-type stress relief seam according to the structure of the main layer film covering it, and the upper insulation block is provided with a second non-through-type stress relief seam aligned with the first through-type stress relief seam provided on the first top plate. The rectangular area of ​​the upper insulation block is larger than that of the first top plate. The first top plate is located in the middle of the rectangle of the upper insulation block. The middle plate and the lower insulation block are the same size as the upper insulation block.

[0017] In some embodiments of the present disclosure, the upper insulation block and the lower insulation block, which are arranged in a rectangular structure, are provided with through-fastener installation notches for installing through-fasteners at the four vertices and midpoints of the long sides, and the middle plate is provided with fixed pads at the four vertices and midpoints of the long sides of the rectangle, and the part of the fixed pad in the lower insulation block is adapted to the shape of the through-fastener installation notch on the lower insulation block, and the fixed pad is fixedly connected to the lower insulation block.

[0018] In some embodiments of the present disclosure, the secondary insulation module in the planar layer is a rectangular structure, and each secondary insulation module includes a second top plate, a cross reinforcement structure and a bottom plate fixedly connected in sequence from top to bottom. An insulation block is provided between the second top plate and the bottom plate. The insulation block is fixed in the space formed by the second top plate, the bottom plate and the cross reinforcement structure, and the insulation block has the same size and shape as the space. The cross center of the cross reinforcement structure is provided with an installation and fixing hole for installing a through fastener. The second top plate and the bottom plate are both provided with installation and fixing holes corresponding to the installation and fixing holes on the cross reinforcement structure. The second top plate is bonded and fixed to the sub-layer film in the sub-layer film layer.

[0019] In some embodiments of the present disclosure, the fastening card plate can be divided into a cross-shaped fastening card plate and a straight-shaped fastening card plate, which are made of non-metallic plate. The upper surface of the fastening card plate is provided with a welding plate and a sealing metal sheet for welding and fixing with the main film layer;

[0020] A mounting hole for arranging the through-fastener is provided at the cross center of the cross-shaped fastening card plate, and the sealing metal sheet is arranged in the mounting hole;

[0021] A mounting hole for arranging the through fastener is provided at the center of the straight-line fastening card plate, and the sealing metal sheet is arranged in the mounting hole;

[0022] In some embodiments of the present disclosure, temperature sensors and combustible gas sensors are respectively installed in the primary shielding space and the secondary shielding space to detect whether there is leakage of ultra-low temperature medium.

[0023] In some embodiments of the present disclosure, the through fastener comprises an upper portion and a lower portion, wherein:

[0024] The upper section includes a cap rod structure, a clamping structure, a double-headed screw and a metal sealing cap. The clamping structure includes a bottom metal plate of a pressure block, a disc spring, a locking cap, a locking plate, a bridge block, four springs, four long bolts, a top metal plate of a pressure block, and four gaskets. The clamping structure is arranged in the installation notch opened on the upper insulation block of the main insulation module, and the lower part of the clamping structure is in contact with the fixed pad.

[0025] The lower section includes a welding base and a nut contained in the welding base, a metal connecting rod and a chamfered thread provided on the upper end of the metal connecting rod. The welding base for the through-fastener is welded at a corresponding position of the hull structure where the through-fastener is placed. The welding base contains a nut, and the metal connecting rod for the through-fastener is installed on the welding base via the nut. The metal connecting rod is inserted into a mounting and fixing hole provided on the cross reinforcement structure of the secondary insulation module.

[0026] The cap rod structure passes through the connecting metal sheet and is connected and fixed with the chamfered thread of the metal connecting rod, and the connecting metal sheet is fixed on the secondary film at the corresponding position. The cap rod structure is locked with the pressing structure.

[0027] In some embodiments of the present disclosure, four vertices of the secondary insulation module having a rectangular structure are provided with distance bolt holes for positioning and connecting with the distance bolts on the hull steel plate.

[0028] In some embodiments of the present disclosure, the first top plate, the middle plate, the second top plate, the cross reinforcement structure and the bottom plate are all made of low-temperature resistant non-metallic materials with a set strength, wherein the low-temperature resistant non-metallic materials can at least withstand a temperature of minus 196 degrees Celsius and have a strength greater than or equal to 4.0 MPa; the upper insulation block, the lower insulation block and the insulation blocks are all made of materials that meet set thermal conductivity requirements, wherein meeting the set thermal conductivity requirements means that the thermal conductivity is not greater than 0.1 W / m·K.

[0029] In some embodiments of the present disclosure, the main film of the main film layer is made of Invar steel or 304L stainless steel that is prefabricated into a set corrugated shape.

[0030] In some embodiments of the present disclosure, each main insulation module is press-connected with the upper portions of six through-fasteners, and the six through-fasteners are respectively arranged at the four corners and the midpoints of the two long sides of the main insulation module arranged in a rectangular structure.

[0031] In some embodiments of the present disclosure, the main film layer is formed by welding a plurality of main films having a first preset size.

[0032] Compared with the prior art, the beneficial effects of the film-type enclosure system provided by the embodiment of the present disclosure are: the main and secondary insulation modules are arranged in an staggered manner, so that the first gap and the second gap are also arranged in an staggered manner, reducing the overall heat leakage at the gap; at the same time, the use of glue is greatly reduced, the construction period is shortened, and the construction environment (humidity and temperature) and process requirements are lowered. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a cross-sectional schematic diagram of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0034] FIG2 is a three-dimensional exploded view of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0035] FIG3 is a three-dimensional exploded view of a main insulation module of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0036] FIG4 is a three-dimensional exploded view of a secondary insulation module of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0037] FIG5 is a schematic diagram of a secondary insulation module of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0038] FIG6 is a three-dimensional exploded view of a straight-line fastening plate of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0039] FIG7 is a three-dimensional exploded view of a cross-shaped fastening plate of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0040] FIG8 is a three-dimensional exploded view of a through-fastener of a membrane-type containment system for carrying cryogenic liquid cargo provided by an embodiment of the present disclosure;

[0041] Reference numerals

[0042] 1-through fastener, 2-secondary insulation layer, 3-secondary film layer, 4-main insulation layer, 5-main film layer, 6-fastening card, 7-resin strip, 8-distance plate, 9-second gap, 10-first gap, 11-main film, 12-cross-shaped fastening card, 13-straight-shaped fastening card, 14-main insulation module, 15-secondary film, 16-secondary insulation module, 17-first top plate, 18-first through-type stress relief seam, 19-upper insulation block, 20-second non-through-type stress relief seam, 21-through fastener installation notch, 22-middle plate, 23-fixing pad, 24-lower insulation block, 25-second top plate, 26-insulation block, 27-cross reinforcement structure, 28-bottom plate, 29-installation fixing hole, 30-distance bolt hole, 31-strip card plate, 32-sealing metal sheet, 33-sealing metal sheet mounting groove, 34-fixed welding plate mounting groove, 35-fixed welding plate, 36-welding base, 37-nut, 38-metal connecting rod, 39-cut thread, 40-connecting metal sheet, 41-cap rod structure, 42-bottom metal plate of pressure block, 43-disc spring, 44-locking cap, 45-locking plate, 46-bridge block, 47-spring, 48-long bolt, 49-top metal plate of pressure block, 50-gasket, 51-double-headed screw, 52-metal sealing cap. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, the present disclosure is described in detail below with reference to the accompanying drawings and specific implementation methods.

[0044] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0045] These and other characteristics of the present application will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0046] It should also be understood that although the present application has been described with reference to certain specific examples, those skilled in the art will be able to implement many other equivalent forms of the present application that have the features described in the claims and are therefore within the scope of protection defined thereby.

[0047] The above and other aspects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

[0048] Specific embodiments of the present application will be described below with reference to the accompanying drawings; however, it should be understood that the embodiments described are merely examples of the present application and may be implemented in a variety of ways. Familiar and / or repetitive functions and structures are not described in detail to clarify the true intent based on the user's historical operations and to avoid obscuring the present application with unnecessary or redundant details. Therefore, the specific structural and functional details described herein are not intended to be limiting, but rather serve merely as a basis and representative basis for the claims to teach those skilled in the art to use the present application in a variety of ways with substantially any appropriate detailed structure.

[0049] This specification may use the phrases "in one embodiment," "in another embodiment," "in a further embodiment," or "in other embodiments," which may all refer to one or more of the same or different embodiments according to the present application.

[0050] The embodiment of the present disclosure provides a film-type containment system for carrying cryogenic liquid cargo. The film-type containment system is used to accommodate ultra-low temperature media, as shown in Figures 1 to 8, and includes a main film layer 5, a fastening card plate 6, a main insulating layer 4, a secondary film layer 3, and a secondary insulating layer 2, which are sequentially connected and fixed to the hull structure (hull steel plate) through a through-fastener 1. That is, a main insulating layer 4 and a fastening card plate 6 are provided between the main film layer 5 and the secondary film layer 3, and a secondary insulating layer 2 is provided between the secondary film layer 3 and the hull structure. The main film layer 5, the fastening card plate 6, the main insulating layer 4, the secondary film layer 3, and the secondary insulating layer 2 are all connected and fixed to the hull structure through a through-fastener 1. At the same time, the space between the main film layer 5 and the secondary film layer 3 forms a main shielding space, and the space between the secondary insulating layer 2 and the hull structure forms a secondary shielding space, effectively building a double-layer sealed ultra-low temperature medium storage carrier, solving the storage and leakage prevention problems of ultra-low temperature media. Specifically,

[0051] The main film layer 5 is provided as the innermost layer of the film-type enclosure system and is in direct contact with the ultra-low temperature medium. The main film layer 5 may be formed by welding together a plurality of main films 11 having a first predetermined size. The main film 11 is made of Invar steel or 304L stainless steel prefabricated in a predetermined corrugated shape, thereby enhancing the thermal deformation capability of the main film 11.

[0052] The main insulating layer 4 includes a plurality of main insulating modules 14 spaced apart and arranged in a matrix. The first gap 10 between two adjacent main insulating modules 14 is filled with a flexible thermal insulation material. The main insulating layer 4 is used to support and insulate the main film layer 5. The main insulating module 14 in the plane layer is a rectangular parallelepiped structure. Each main insulating module 14 includes a first top plate 17, an upper thermal insulation block 19, a middle plate 22 and a lower thermal insulation block 24 fixedly connected from top to bottom. The first top plate 17 is located at the top of each component in the main insulating module 14. It is a rectangular plate. The structure of the main layer film 11 covered thereon is provided with a first through-type stress relief seam 18, the upper insulation block 19 is located below the first top plate 17, and is also a rectangular plate, which is fixedly connected to the first top plate 17 by glue, and the upper insulation block 19 is provided with a second non-through-type stress relief seam 20 which is aligned with the first through-type stress relief seam 18 provided on the first top plate 17, the rectangular area of ​​the upper insulation block 19 is larger than the first top plate 17, and the first top plate 17 is located in the middle of the rectangle of the upper insulation block 19, specifically, it can be located at the center of the rectangle of the upper insulation block 19. The middle plate 22 and the lower insulation block 24, which are sequentially arranged at the lower part of the upper insulation block 19, are the same size as the upper insulation block 19. The middle plate 22 is fixedly connected to the upper insulation block 19 by glue and completely overlaps with the upper insulation block 19. The lower insulation block 24 is fixedly connected to the middle plate 22 by glue and completely overlaps with the middle plate 22. The four vertices and midpoints of the long sides of the upper insulation block 19 and the lower insulation block 24 arranged in a rectangular structure are provided with a through fastener installation notch 21 for installing the through fastener 1. The shape and size of the installation notches on the upper insulation block 19 and the lower insulation block 24 are the same. Similarly, the middle plate 22 is provided with fixed pads 23 at the four vertices and the midpoint of the long side of the rectangle. The portion of the fixed pad 23 in the lower insulation block 24 is adapted to the shape of the through-fastener installation notch 21 on the lower insulation block 24, that is, the shape and size of the fixed pad 23 are consistent with the shape and size of the through-fastener installation notch 21 of the lower insulation block 24, and can fill the installation notch formed on the lower insulation block 24. The portion where the fixed pad 23 contacts the lower insulation block 24 is fixed by glue. Finally, the above-mentioned main insulation module 14 is formed by using two layers of non-metallic plates and two layers of thermal insulation materials.

[0053] In the above embodiment, the fixed pad 23 can be an integrally formed design with the middle plate 22, or it can be fixedly connected to the middle plate 22. If the fixed pad 23 and the middle plate 22 are not integrally formed, the middle plate is provided with through-fastener installation notches 21 for installing the through-fasteners 1 at the four vertices and the midpoint of the long side of the rectangle, and then the fixed pad 23 is arranged in the through-fastener installation notches 21 of the middle plate 22 and fixedly connected to the middle plate 22.

[0054] The fastening card plate 6 is arranged between the main film layer 5 and the main insulating layer 4. The fastening card plate 6 includes at least one strip card plate 31 located at the upper part of the first gap 10 and mounted on the main insulating module 14 on both sides of the first gap 10. The strip card plate 31 is made of non-metallic plate material. The upper surface of the fastening card plate 6 is provided with a welding plate 35 and a sealing metal sheet 32 ​​for welding and fixing with the main film layer 5. Specifically, the fastening card plate 6 is provided with mounting and fixing holes 29 for connecting and fixing the through-fasteners 1 at the four vertices and the midpoints of the long sides of the main insulating module 14 with a rectangular structure. The mounting and fixing holes 29 on the fastening card plate 6 are within the sealing metal sheet mounting groove 33 of the strip card plate 31, and the sealing metal sheet 32 ​​is also provided with through-fastener mounting and fixing holes 29 at the corresponding position. The sealing metal sheet 32 ​​is connected and fixed to the strip card plate 31 through the through-fastener 1, that is, the main insulating module 14 with a rectangular structure is fixed at the four vertices and the midpoints of the long sides of the rectangular structure. The mounting fixing hole 29 on the fastening card plate 6 is connected and fixed to the through fastener 1; the strip card plate 31 is also provided with a fixed welding plate mounting groove 34 for installing the fixed welding plate 35. The fixed welding plate mounting groove 34 is arranged in a rectangular structure according to the arrangement of the main layer film 11. The fixed welding plate 35 is adapted to the size of the fixed welding plate mounting groove 34, but its length is slightly smaller than the length of the fixed welding plate mounting groove 34. The fixed welding plate 35 is connected and fixed to the strip card plate 31 by riveting or bonding.

[0055] The secondary film layer 3 is located on the side of the primary insulating layer 4 away from the cryogenic medium, at the interface between the primary insulating layer 4 and the secondary insulating layer 2. The secondary film layer 3 includes a plurality of secondary films 15 of a second preset size connected in a spliced ​​manner. When the primary film layer 5 leaks, the secondary film layer 3 can receive the cryogenic medium, thereby avoiding safety risks caused by contact between the hull structure and the cryogenic medium. The secondary film 15 is made of a flexible sealing material that meets cryogenic resistance requirements.

[0056] The secondary insulating layer 2 includes a plurality of secondary insulating modules 16 spaced apart and arranged in a matrix, and the second gap 9 between two adjacent secondary insulating modules 16 is filled with a flexible thermal insulation material; wherein the secondary insulating module 16 in the plane area is a rectangular parallelepiped structure, and each secondary insulating module 16 includes a second top plate 25, a cross reinforcement structure 27 and a bottom plate 28 fixedly connected from top to bottom. The second top plate 25 is located at the top of each component in the secondary insulating module 16 and is a rectangular plate. At the same time, each secondary insulating module 16 also includes four thermal insulation blocks 2 6. The second top sheet 25 is bonded and fixed to the sub-layer film 15 in the sub-layer film layer 3. The cross reinforcement structure 27 is located below the second top sheet 25, and its periphery overlaps with the second top sheet 25. At the same time, the cross reinforcement structure 27 and the second top sheet 25 can be connected by glue or rivets. The bottom sheet 28 is located below the cross reinforcement structure 27. The size and shape of the bottom sheet 28 are the same as those of the second top sheet 25, and its periphery overlaps with the cross reinforcement structure 27 and the second top sheet 25. The bottom sheet 28 and the cross reinforcement structure 27 are glued or rivets. The second top plate 25 and the bottom plate 28 are connected by rivets. An insulation block 26 is provided between the second top plate 25 and the bottom plate 28. The insulation block 26 is fixed in the space formed by the second top plate 25, the bottom plate 28 and the cross reinforcement structure 27, and the insulation block 26 has the same size and shape as the space, that is, the size and shape of the insulation block 26 can be determined according to the size and shape of the space formed by the periphery of the second top plate 25 and the bottom plate 28 and the cross reinforcement structure 27. At the same time, the insulation block 26 should fill the entire space and be in contact with the second top plate 25, the bottom plate 28 and the cross reinforcement structure 27. 7 coincide with the periphery, the insulation block 26 is connected and fixed with glue at the contact points with the second top plate 25, the bottom plate 28 and the cross reinforcement structure 27, and the cross center of the cross reinforcement structure 27 is provided with a mounting and fixing hole 29 for installing the through fastener 1, and the second top plate 25 and the bottom plate 28 are provided with mounting and fixing holes 29 corresponding to the mounting and fixing holes 29 on the cross reinforcement structure 27; that is, the secondary insulation module 16 with a rectangular structure is formed with a mounting and fixing hole 29 for installing and fixing the through fastener 1 in the center of the rectangular parallelepiped along the thickness direction.

[0057] The secondary insulation module 16 is fixedly connected to the hull steel plate through its lower surface. A distance plate 8 and a resin strip 7 are provided between the secondary insulation module 16 and the hull steel plate for flat installation of the secondary insulation module 16 and for distance installation between the module and the hull steel plate. At the same time, distance bolt holes 30 are provided at the four vertices of the secondary insulation module 16 for positioning and connecting with distance bolts on the hull steel plate.

[0058] Among them, the space between the main film layer 5 and the secondary film layer 3 forms the main shielding space, and the space between the secondary film layer 3 and the hull structure forms the secondary shielding space. Both the main shielding space and the secondary shielding space are filled with inert protective gas.

[0059] For the above-mentioned membrane-type containment system, when installing it, it is necessary to first mark the bulkhead of the hull structure, weld the studs set perpendicular to the bulkhead at the position on the bulkhead for placing the distance plate 8 according to the marking, and install the distance plate 8 mounted on the studs, wherein the four corners of the distance plate 8 are symmetrically arranged with respect to the center line of the distance plate and are provided with four through holes, and a stud is passed through each through hole.

[0060] The through-fastening part includes: an upper section and a lower section. The upper section includes a cap rod structure 41, a clamping structure, a double-headed screw 51 and a metal sealing cap 52. The clamping structure includes a bottom metal plate 42 of a pressure block, a disc spring 43, a locking cap 44, a locking plate 45, a bridge block 46, four springs 47, four long bolts 48, a top metal plate 49 of a pressure block, and four gaskets 50; the lower section includes a welding base 36 and a nut 37 contained in the welding base 36, a metal connecting rod 38 and a chamfered thread 39 provided at the upper end of the metal connecting rod 38, wherein the clamping structure is provided at the upper part of the main insulating module 14. In the installation notch opened on the insulation block 19, the lower part of the clamping structure fits with the fixed pad 23, and the cap rod structure 41 passes through the connecting metal sheet 40 and is connected and fixed with the chamfered thread 39 of the metal connecting rod 38, and the connecting metal sheet 40 is fixed to the secondary film 15 at the corresponding position, and the cap rod structure 41 locks the clamping structure; the welding base 36 of the through fastener 1 is welded at the corresponding position of the hull structure where the through fastener 1 is placed, and the welding base contains a nut 37, and the metal connecting rod 38 of the through fastener is installed on the welding base 36 through the nut 37, and the metal connecting rod 38 is passed through the installation and fixing hole 29 set on the cross reinforcement structure 27 of the secondary insulation module 16.

[0061] Each stud on the distance plate 8 corresponds to a corner of four different, adjacent secondary insulation modules 16. Each of the sub-insulation modules 16 in the flat area has distance bolt holes 30 at each corner. These holes are designed to accommodate the studs inserted through the distance plate 8 and the fastening nuts threaded into them. Furthermore, the bottom plate 28 also has openings concentric with the distance bolt holes 30. Furthermore, the second top plate 25 and the insulation block 26 also have distance bolt holes 30 concentric with the through-holes, with a diameter 2-4 times that of the through-holes. This facilitates the use of washers, fastening nuts, and tooling to secure the distance plate. Furthermore, after the studs on the four secondary insulation modules around each distance plate 8 are tightened by nuts, the distance bolt holes 30 opened on each secondary insulation module 16 are filled with plungers made of the same material as the insulation block, so that each secondary insulation module 16 can be interconnected, which plays an auxiliary anchoring role for each secondary insulation module 16.

[0062] In this embodiment, the distance plate 8 is made of plywood or a plastic alternative material that meets the rigidity requirements, and the thickness is set to at least one of 1 mm, 2 mm, 5 mm or 10 mm. The distance plate is used for leveling. By stacking and combining distance plates of different thicknesses, the distance between the bottom plate 28 of the secondary insulation module 16 and the bulkhead is 10 mm; the aperture of the through hole on the distance plate 8 is larger than the outer diameter of the thread on the stud by 0.5-2 mm.

[0063] After the secondary insulation module 16 is installed on the distance plate 8, the through fastener 1 is installed, and the metal connecting rod 38 of the through fastener 1 is passed through the installation and fixing hole 29 in the middle of the secondary insulation module 16, and the cap rod structure 41 of the upper part of the through fastener 1 (specifically, the cylindrical cap provided by the cap rod structure 41 of the upper part) is screwed and fixed to the metal connecting rod 38. The connection of the lower part of the through fastener 1 plays a major anchoring role for each secondary insulation module 16 in the plane area. At the same time, the use of the distance plate 8, the resin strip 7 and the lower part of the through fastener 1 can effectively anchor the secondary insulation layer 2 of the entire enclosure system to the inner bulkhead.

[0064] In this embodiment, during the installation of the secondary insulation module 16 on the upper part and top of the bulkhead, after the secondary insulation module 16 and the distance plate 8 are installed, a lifting device is required for temporary stabilization, and after the cap rod structure 41 passing through the upper part of the fastener 1 is tightened and fixed with the metal connecting rod 38, the lifting device is removed.

[0065] The bottom plate 28 of the secondary insulation module 16 has four corners with openings for mounting studs, the diameter of which is 0.5-2 mm larger than the outer diameter of the thread on the stud.

[0066] After the secondary insulating layer 2 is installed, the secondary film layer 3 is installed, and the plurality of secondary films 15 with the second preset size connected in a splicing manner are bonded and fixed to the second top plate 25 of the secondary insulating module 16 respectively.

[0067] After completing the installation of the secondary film layer 3, the main insulation module 14 is installed. In the plane area, each main insulation module 14 is compressed and connected with the upper parts of the six through fasteners 1. The six through fasteners 1 are respectively arranged at the four corners and the midpoints of the two long sides of the main insulation module 14 arranged in a rectangular structure; after the four main insulation modules 14 corresponding to the same corner are placed, the corresponding compression structure of the through fastener 1 is installed at the corner, and the bottom metal plate 42 of the compression block of the compression structure is pressed on the middle plate 22 of the four adjacent main insulation modules 14. At the same time, the bottom metal plate 42 of the compression block of the compression structure of the through fastener 1 arranged at the midpoint of the long side of two adjacent main insulation modules 14 is pressed on the middle plate 22 of the adjacent main insulation modules 14. The compression structures are respectively fixedly connected and locked with the upper end of the metal connecting rod.

[0068] In some embodiments of the present disclosure, the fastening card plate 6 has a cross-shaped structure or a straight-line structure, that is, the fastening card plate 6 includes a cross-shaped fastening card plate 12 and a straight-line fastening card plate 13, and is made of a non-metallic plate that is easy to process and has low-temperature resistance. The upper surface of the fastening card plate 6 is in contact with the main film layer 5, and is provided with a fixed welding plate 35 and a sealing metal sheet 32 ​​for welding with the main film 11. Specifically, the four long sides of the cross-shaped fastening card plate 12 and the two long sides of the straight-line fastening card plate 13 are fixed with fixed welding plates 35 for welding and fixing with the main film 11; at the same time, the cross center of the cross-shaped fastening card plate 12 and the straight center of the straight-line fastening card plate 13 are provided with an installation and fixing hole 29 for setting the through fastener 1, thereby facilitating the installation and fixation of the through fastener 1. As an example, the fastening card plate 6 is made of plywood or an alternative material that meets the stiffness requirements, and the thickness of the card plate ranges from 6mm to 15mm; a circular sealing metal sheet mounting groove 33 with a diameter of 60-120mm and a depth of 1.5-3mm is formed at the upper end of the mounting and fixing hole 29 on the fastening card plate 6, and a sealing metal sheet 32 ​​with a center hole matching the groove size is embedded in the groove.

[0069] After the fastening card plate 6 is installed, the main layer film layer 5 is installed, and the boundaries of each main layer film 11 are welded and fixed to the fixed welding plate 35 or the sealing metal sheet 32 ​​on the fastening card plate 6 provided on the main insulation module 14, specifically including: fixing the first main layer film 11 installed on the welding plate to the fixed welding plate 35 or the sealing metal sheet 32 ​​by intermittent spot welding, overlapping the main layer film 11 adjacent to the first main layer film 11 on the first main layer film 11, sealingly welding the overlapping part along the entire edge line, and welding the boundary of the main layer film 11 on the sealing metal sheet 32 ​​in the through hole in the middle position of the fastening card plate 6 to the sealing metal sheet 32, and welding the upper end metal sealing cap 52 of the upper part of the through fastener 1 to the sealing metal sheet 32 ​​to achieve sealing of the entire main layer film layer 5.

[0070] In some embodiments of the present disclosure, temperature sensors and combustible gas sensors are respectively installed in the primary shielding space and the secondary shielding space to detect whether there is leakage of ultra-low temperature media, for example, to detect whether there is leakage of LNG.

[0071] In the above embodiment, the first top plate 17, the middle plate 22, the second top plate 25, the cross reinforcement structure 27 and the bottom plate 28 are all made of low-temperature resistant non-metallic materials with a set strength, wherein the low-temperature resistant non-metallic materials can at least withstand a temperature of minus 196 degrees Celsius and have a strength greater than or equal to 4.0 MPa.

[0072] At the same time, the upper insulation block 19, the lower insulation block 24, and the insulation block 26 are all made of materials that meet the set thermal conductivity requirements, wherein the set thermal conductivity requirements are that the thermal conductivity is not greater than 0.1 W / (m·K).

[0073] The above embodiments are merely exemplary embodiments of the present disclosure and are not intended to limit the present disclosure. The scope of protection of the present disclosure is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present disclosure within the essence and scope of protection of the present disclosure, and such modifications or equivalent substitutions shall also be deemed to fall within the scope of protection of the present disclosure.

Claims

1. A membrane containment system for carrying cryogenic liquid cargo, wherein: The film-type containment system is used to accommodate ultra-low temperature media, and includes a main film layer, a fastening card plate, a main insulating layer, a secondary film layer and a secondary insulating layer, which are sequentially connected and fixed to the hull structure through penetrating fasteners. The main film layer, the main insulating layer, the secondary film layer and the secondary insulating layer enclose a cryogenic liquid cargo storage tank for accommodating ultra-low temperature media. In the film-type containment system, The main thin film layer is in contact with the ultra-low temperature medium; The main insulating layer comprises a plurality of main insulating modules which are spaced apart and arranged in a matrix, and a first gap between two adjacent main insulating modules is filled with a flexible thermal insulation material; The fastening card is arranged between the main film layer and the main insulating layer, and the fastening card includes at least one strip card located at the upper part of the first gap and mounted on the main insulating module on both sides of the first gap; The secondary film layer is located at the interface between the main insulating layer and the secondary insulating layer, and the secondary film in the secondary film layer is made of a flexible sealing material that meets the low temperature resistance condition; The secondary insulating layer comprises a plurality of secondary insulating modules which are spaced apart and arranged in a matrix, and the second gap between two adjacent secondary insulating modules is filled with a flexible thermal insulation material; The secondary insulation module is fixedly connected to the hull steel plate through the lower surface, and a distance plate and a resin strip are provided between the insulation module and the hull steel plate for flat installation of the secondary insulation module and for fixed installation between the insulation module and the hull steel plate; The space between the main film layer and the secondary film layer forms a main shielding space, the space between the secondary insulating layer and the hull structure forms a secondary shielding space, and both the main shielding space and the secondary shielding space are filled with inert protective gas.

2. A membrane type containment system for carrying cryogenic liquid cargo according to claim 1, wherein: The main insulation module in the plane layer has a rectangular structure. Each main insulation module includes a first top plate, an upper insulation block, a middle plate and a lower insulation block which are fixedly connected in sequence from top to bottom. The first top plate is provided with a first through-type stress release seam according to the structure of the main layer film covered thereon. The upper insulation block is provided with a second non-through-type stress release seam which is aligned with the first through-type stress release seam provided on the first top plate. The rectangular area of ​​the upper insulation block is larger than that of the first top plate. The first top plate is located in the middle of the rectangle of the upper insulation block. The middle plate and the lower insulation block are the same size as the upper insulation block.

3. A membrane type containment system for carrying cryogenic liquid cargo according to claim 2, wherein: The four vertices and the midpoints of the long sides of the upper insulation block and the lower insulation block arranged in a rectangular parallelepiped structure Through-fastener installation notches for installing through-fasteners are provided at the four vertices of the middle plate and the midpoint of the long side of the rectangle. The part of the fixed pad in the lower insulation block is adapted to the shape of the through-fastener installation notches on the lower insulation block, and the fixed pad is fixedly connected to the lower insulation block.

4. A membrane type containment system for carrying cryogenic liquid cargo according to claim 3, wherein: The secondary insulation module in the plane layer is a rectangular structure, and each secondary insulation module includes a second top plate, a cross reinforcement structure and a bottom plate fixedly connected in sequence from top to bottom. An insulation block is provided between the second top plate and the bottom plate. The insulation block is fixed in a space formed by the second top plate, the bottom plate and the cross reinforcement structure, and the insulation block has the same size and shape as the space. A mounting and fixing hole for installing a through fastener is provided at the cross center of the cross reinforcement structure. The second top plate and the bottom plate are both provided with mounting and fixing holes corresponding to the mounting and fixing holes on the cross reinforcement structure. The second top plate is bonded and fixed to the secondary film in the secondary film layer.

5. A membrane type containment system for carrying cryogenic liquid cargo according to claim 4, wherein: The fastening card plate can be divided into a cross-shaped fastening card plate and a straight-shaped fastening card plate, and is made of a non-metallic plate. The upper surface of the fastening card plate is provided with a welding plate and a sealing metal sheet for welding and fixing with the main film layer; A mounting hole for setting the through fastener is provided at the center of the cross of the cross-shaped fastening card plate, and the sealing metal sheet is arranged in the mounting hole; A mounting hole for setting the through fastener is provided at the center of the straight-line fastening card plate, and the sealing metal sheet is arranged in the mounting hole.

6. A membrane type containment system for carrying cryogenic liquid cargo according to claim 4, wherein: Temperature sensors and combustible gas sensors are respectively installed in the primary shielding space and the secondary shielding space to detect whether there is leakage of ultra-low temperature medium.

7. A membrane containment system for carrying cryogenic liquid cargo according to claim 4, wherein: The through fastener comprises an upper portion and a lower portion, wherein: The upper section includes a cap rod structure, a clamping structure, a double-headed screw and a metal sealing cap, the clamping structure includes a bottom metal plate of a clamping block, a disc spring, a locking cap, a locking plate, a bridge block, four springs, four long bolts, a top metal plate of a clamping block, and four gaskets, the clamping structure is arranged in the installation notch opened on the upper insulation block of the main insulation module, and the lower part of the clamping structure is in contact with the fixed pad; The lower section includes a welding base and a nut contained in the welding base, a metal connecting rod and a chamfered thread arranged on the upper end of the metal connecting rod, and is welded at a corresponding position of the hull structure where the through fastener is placed. A welding base connected to the through-fastener, wherein the welding base contains a nut, and a metal connecting rod through the fastener is installed on the welding base through the nut, and the metal connecting rod is inserted into a mounting and fixing hole provided on the cross reinforcement structure of the secondary insulation module; The cap rod structure passes through the connecting metal sheet and is connected and fixed with the chamfered thread of the metal connecting rod, and the connecting metal sheet is fixed on the secondary film at the corresponding position, and the cap rod structure is locked with the clamping structure.

8. A membrane type containment system for carrying cryogenic liquid cargo according to claim 4, wherein: The four vertices of the secondary insulation module with a rectangular structure are all provided with distance bolt holes for positioning and connecting with the distance bolts on the hull steel plate.

9. A membrane type containment system for carrying cryogenic liquid cargo according to claim 4, wherein: The first top plate, the middle plate, the second top plate, the cross reinforcement structure and the bottom plate are all made of a low-temperature resistant non-metallic material with a set strength, wherein the low-temperature resistant non-metallic material can withstand a temperature of at least minus 196 degrees Celsius and has a strength greater than or equal to 4.0 MPa; The upper insulation block, the lower insulation block and the insulation block are all made of materials that meet the set thermal conductivity requirements, wherein the set thermal conductivity requirements are that the thermal conductivity is not greater than 0.1 W / m·K.

10. A membrane type containment system for carrying cryogenic liquid cargo according to claim 4, wherein: The main film of the main film layer is made of Invar steel or 304L stainless steel prefabricated into a set corrugated shape.

11. A membrane containment system for carrying cryogenic liquid cargo according to claim 4, wherein: Each main insulating module is compressed and connected with the upper parts of six through-fasteners, and the six through-fasteners are respectively arranged at the four corners and the midpoints of the two long sides of the main insulating module arranged in a rectangular structure.

12. A membrane type containment system for carrying cryogenic liquid cargo according to claim 4, wherein: The main film layer is formed by welding a plurality of main films having a first preset size.

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