Sealed insulated tank for storing liquefied gas and ship for transporting liquefied gas

Abstract

The application discloses a sealed and insulated tank for storing liquefied gas and a ship for transporting liquefied gas. The sealed and insulated tank is arranged in a supporting structure, the supporting structure comprises an upper supporting wall; the upper supporting wall and the sealed membrane and the thermal insulation layer are partially interrupted to bound a loading and unloading opening, the loading and unloading opening is used for allowing a liquefied gas loading and unloading pipeline to pass through the loading and unloading opening, and the tank comprises a cover arranged in the loading and unloading opening; the sealed membrane comprises a terminal bent connecting part at the interruption, and the terminal bent connecting part is fixed to the supporting structure through an upper surface or a lower surface of a sealed membrane connecting part extending in a wall thickness direction. The terminal bent connecting part of the sealed membrane is welded to the upper surface of the sealed membrane connecting part, the effective welding area is greatly increased without increasing the thickness of the connecting part, the welding strength is greatly improved, meanwhile, the thin connecting part significantly reduces the heat bridge effect, reduces the cold leakage amount, and effectively solves the contradiction between the sealing and the thermal insulation at the dome.

Description

Technical Field

[0001] This invention relates to the field of liquefied natural gas (LNG) storage tank enclosure membrane manufacturing technology, specifically a sealed and insulated tank for storing liquefied gas and a ship for transporting liquefied gas. Background Technology

[0002] Cryogenic membrane tanks are large storage tank structures used to store cryogenic media such as liquefied natural gas (LNG), typically for the storage and long-distance transportation of LNG. From the inside out, a cryogenic membrane tank generally consists of a main shielding layer, a main plywood layer, a secondary shielding layer, and an insulation box.

[0003] Due to the low temperature and easy expansion characteristics of LNG, the inner wall of cryogenic membrane tanks is usually made of corrugated plates. The corrugated surface of the plates can accommodate contraction, thus addressing the problem of LNG's supercooled contraction. In addition to the corrugated plate inner membrane tank, cryogenic membrane tanks also require the installation of components such as pump towers and cooling equipment. The pump tower runs through the inside of the membrane tank for the input and output of LNG.

[0004] In the conventional fabrication of cryogenic membrane tanks, the pump tower's piping enters and exits the tank through a dome structure located at the top. The sealing membrane and insulation layer of the membrane tank are interrupted by openings in the dome structure. The sealing membrane requires special welding at the interruption point, typically by welding its end to the side of a metal connector that penetrates the insulation layer. To ensure weld strength, the thickness of the connector needs to be increased. However, a thicker metal connector will create significant thermal bridges, leading to a substantial increase in cold leakage and exacerbating LNG evaporation. Conversely, reducing the connector thickness results in insufficient welding area, low weld strength, and the sealing membrane becoming prone to cracking under thermal cycling and vibration, posing a leakage risk.

[0005] Therefore, there is a need to provide a sealed, insulated tank for storing liquefied gases and a ship for transporting liquefied gases, in order to at least partially solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a sealed and insulated tank for storing liquefied gas and a ship for transporting liquefied gas, thereby solving the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] The present invention provides a sealed and insulated tank for storing liquefied gas. The sealed and insulated tank is arranged in a support structure. The sealed and insulated tank includes a plurality of tank walls, which are connected to each other and fixed to the support structure. The plurality of tank walls include at least one sealing membrane and at least one insulation layer, which is disposed between the sealing membrane and the support structure.

[0009] The support structure includes an upper support wall; the upper support wall, the sealing membrane, and the insulation layer are partially interrupted to define a loading and unloading opening, which is used to allow a liquefied gas loading and unloading pipeline to pass through the loading and unloading opening; the tank includes a cover disposed in the loading and unloading opening; the sealing membrane includes an end-bent connection at the interruption point, which is fixed to the support structure by the upper or lower surface of a sealing membrane connector extending in the wall thickness direction.

[0010] The end bend of the sealing membrane is fixed by the upper or lower surface of the sealing membrane connector extending in the wall thickness direction. Compared with the side of the sealing membrane connector, the upper and lower surfaces have sufficient welding area for overlapping the sealing membrane, resulting in higher welding strength and more stable sealing membrane. Welding on the side of the sealing membrane connector requires increasing the thickness of the sealing membrane connector. The sealing membrane connector also needs to pass through the insulation layer, which will weaken the insulation effect of the insulation layer and cause cold leakage channels in the sealed insulation tank.

[0011] Preferably, the sealing membrane connector includes a first connecting portion and a second connecting portion, the first connecting portion being fixedly connected to the support structure, and the sealing membrane being sealed to the upper surface of the second connecting portion;

[0012] The dimension of the first connecting portion in the direction perpendicular to the wall thickness is greater than the dimension of the second connecting portion in the direction perpendicular to the wall thickness, so that the height of the sealing film connected to the second connecting portion is lower than or equal to the height of the upper surface of the first connecting portion.

[0013] By designing the sealing membrane connector as two connecting parts with a size difference, the first connecting part is fixedly connected to the support structure and bears the pressure from the upper cover or insulation box, while the second part is welded to the sealing membrane. This protects the welded part of the sealing membrane from the pressure or impact from above, prevents damage to the welded part, and enhances the stability of the sealing membrane.

[0014] Preferably, the end bend connecting portion is partially connected to the upper surface of the second connecting portion;

[0015] The insulation layer includes an end insulation module disposed below the sealing membrane connector;

[0016] The size of the overlapping area between the end bend connection and the second connection is determined based on the dimensions of the sealing film connector, the end bend connection, and the end insulation module in the wall thickness direction.

[0017] Both the end bend connection and the second connection have sufficient welding area, and partial welding of the two can meet the welding strength requirements. In the actual assembly process of the sealed heat insulation tank, the actual size and installation position of the sealing membrane connector, the end bend connection and the end heat insulation module may have errors. The end bend connection can be adjusted and partially welded to the second connection according to the actual assembly situation, providing sufficient redundancy for construction.

[0018] Preferably, the sealed heat insulation tank includes a compensation support plate disposed above the end heat insulation module;

[0019] The upper surface of the compensation support plate and the upper surface of the second connecting part are located on the same horizontal plane.

[0020] By setting up a compensation support plate to compensate for the size difference with the end insulation module, it is ensured that the end bending connection can be installed on a horizontal plane.

[0021] Preferably, the sealed heat-insulating tank includes a flexible covering layer that fills the gap between the sealing film and the covering.

[0022] By filling the gap between the sealing membrane and the cover with a flexible covering layer, the welded part of the sealing membrane can be protected from pressure or impact from above, preventing damage to the welded part, enhancing the stability of the sealing membrane, and ensuring the flatness of the upper surface of the sealing membrane connector.

[0023] Preferably, the difference between the dimension of the first connecting portion in the direction perpendicular to the wall thickness and the dimension of the second connecting portion in the direction perpendicular to the wall thickness is determined according to the thickness of the sealing film; and / or,

[0024] The difference between the dimension of the first connecting portion in the direction perpendicular to the wall thickness and the dimension of the second connecting portion in the direction perpendicular to the wall thickness is 1.5 mm to 2 mm; and / or,

[0025] The second connecting portion has a dimension of 10 mm to 200 mm in the wall thickness direction.

[0026] Preferably, the sealing membrane is a primary sealing membrane, and the insulation layer is a primary insulation layer; the sealed insulation tank includes, in the thickness direction from the outside to the inside of the sealed insulation tank: a secondary insulation layer fixed to the support structure; a secondary sealing membrane carried by the secondary insulation layer; the primary insulation layer carried by the secondary sealing membrane; and the primary sealing membrane carried by the primary insulation layer and used for contact with the liquefied gas.

[0027] Preferably, the sealing membrane connector is a primary sealing membrane connector; the sealed heat insulation tank further includes a secondary sealing membrane connector extending in the wall thickness direction;

[0028] The secondary sealing membrane is fixed to the support structure at the interruption point by the secondary sealing membrane connector;

[0029] The primary sealing membrane connector and the secondary sealing membrane connector are connected by a reinforcing wing plate.

[0030] Preferably, the primary sealing membrane and the secondary sealing membrane comprise a plurality of corrugated metal plates juxtaposed in a repeating pattern and welded together in a sealing manner, wherein the metal plates of the primary sealing membrane and the secondary sealing membrane are made of stainless steel; and / or,

[0031] The corrugations of the primary sealing membrane face inwards into the tank; and / or,

[0032] The corrugations of the secondary sealing membrane face outwards from the tank; and / or,

[0033] The corrugated plate of the secondary sealing membrane includes a main body portion and an edge portion disposed around the main body portion. The edge portion is used to connect with the edge portion of another corrugated plate. The corrugations have protrusions and recesses. The recesses are disposed on the main body portion, and the protrusions are disposed on the edge portion. The protrusions are used to connect with the protrusions of another corrugated metal plate.

[0034] By setting protrusions and recesses in the corrugated portion of the corrugated plate along the direction perpendicular to the wall thickness, and connecting the protrusions and recesses through a torsion joint, the original continuous circulation channel in the corrugated portion is blocked by the torsion structure at the "convex-concave" joint, thereby disrupting the conditions for stable convection of gas in the long continuous channel. This inhibits heat transfer, improves the thermal insulation performance of the cryogenic liquefied gas system, effectively reduces LNG evaporation in the cryogenic liquefied gas system, and thus reduces cargo loss and saves costs.

[0035] The present invention also provides a ship for transporting liquefied gases, the ship comprising a hull and a sealed, insulated tank for storing liquefied gases as described above disposed in the hull.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. Simultaneously improve sealing reliability and thermal insulation performance: The end of the sealing membrane is bent and welded to the upper and lower surfaces of the sealing membrane connector, rather than the side. Without increasing the thickness of the connector, the effective welding area is greatly increased, and the welding strength is greatly improved. At the same time, the thinner connector significantly reduces the thermal bridge effect, reduces cold leakage, and effectively solves the contradiction between sealing and thermal insulation.

[0038] 2. Effective protection of welded parts and improved structural durability: The stepped sealing membrane connector makes the welded part of the sealing membrane lower than the upper surface of the first connection part, forming a natural protective groove. This avoids the pressure of the upper cover and insulation box acting directly on the welded part, preventing welding fatigue and cracking, and greatly extending the service life.

[0039] 3. Improve construction tolerance and reduce construction difficulty: The end bending connection and the second connection adopt a partial welding method. The overlapping area can be adjusted within a certain range according to the actual assembly error, which provides sufficient redundancy for on-site construction and shortens the construction cycle.

[0040] 4. Ensure installation flatness and improve sealing quality: By setting up a compensation support plate, the dimensional difference between the end insulation module and the sealing membrane connector is compensated, so that the end bending connection can be installed on the same horizontal plane, avoiding welding stress concentration caused by uneven installation.

[0041] 5. Further enhance the protective effect: Filling the gap between the sealing membrane and the cover with a flexible covering layer can not only absorb vibration and impact, but also prevent foreign objects from entering and damaging the welded parts, thus further improving the reliability of the structure. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the sealed and insulated tank for storing liquefied gas in Embodiment 1 of the present invention;

[0043] Figure 2 This is a cross-sectional view of the loading and unloading opening (2) at the top of the sealed insulated tank for storing liquefied gas in Embodiment 1 of the present invention;

[0044] Figure 3 for Figure 2 A schematic diagram showing the details of a sealed insulated tank (A).

[0045] Figure 4 This is a schematic diagram of the corrugated plate of the sealed and insulated tank for storing liquefied gas in Embodiment 1 of the present invention.

[0046] Figure 5 This is a cross-sectional view of the tank of the ship in Embodiment 2 of the present invention.

[0047] Explanation of reference numerals in the attached figures:

[0048] 1—Upper Support Wall

[0049] 2—Loading / Unloading Opening

[0050] 3—Covering

[0051] 4—Sealing membrane connector

[0052] 41—First connecting part

[0053] 42—Second connecting part

[0054] 5—End bending connection

[0055] 6—End insulation module

[0056] 7—Compensation Support Plate

[0057] 8—Shell

[0058] 9—Sealed Insulated Tank

[0059] 11—Primary sealing membrane

[0060] 12—Secondary sealing membrane

[0061] 21—Primary Insulation Layer

[0062] 22—Secondary Insulation Layer

[0063] 111—Main Body

[0064] 112—Edge section

[0065] 121—Protrusion

[0066] 122—Depression

[0067] 140—Twist section. Detailed Implementation

[0068] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0069] In the description of this invention, it should be understood that, unless otherwise stated, the terms "center," "perpendicular to the wall thickness direction," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0070] Furthermore, unless otherwise stated, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0071] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0072] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0073] Example 1

[0074] Please see the appendix Figure 1 As shown, this embodiment provides a sealed and insulated tank for storing liquefied gas. The sealed and insulated tank is arranged in a support structure and consists of multiple tank walls that are connected to each other and fixed to the support structure. The multiple tank walls include at least one top wall, a bottom wall, and multiple side walls extending between the top wall and the bottom wall. The sealed and insulated tank also includes at least one liquefied gas loading and unloading tower that extends between the top wall and the bottom wall. A base is provided in the bottom loading and unloading tower base area, and a loading and unloading opening 2 is provided at the top.

[0075] Please see the appendix Figure 2 - Appendix Figure 3As shown, multiple tank walls include at least one sealing membrane and at least one insulation layer, the insulation layer being disposed between the sealing membrane and the support structure; the support structure includes an upper support wall 1; the upper support wall 1, the sealing membrane, and the insulation layer are partially interrupted, thereby defining a loading and unloading opening 2, the loading and unloading opening 2 for allowing liquefied gas loading and unloading pipelines to pass through the loading and unloading opening 2, the tank including a cover 3 disposed in the loading and unloading opening 2; the sealing membrane includes an end-bent connection 5 at the interruption point, the end-bent connection 5 being fixed to the support structure by the upper or lower surface of a sealing membrane connector 4 extending in the wall thickness direction.

[0076] The end bend connection 5 of the sealing membrane is fixed by the upper or lower surface of the sealing membrane connector 4 extending in the wall thickness direction. Compared with the side of the sealing membrane connector 4, the upper and lower surfaces have sufficient welding area for overlapping the sealing membrane, resulting in higher welding strength and more stable sealing membrane. Welding on the side of the sealing membrane connector 4 requires increasing the thickness of the sealing membrane connector 4. The sealing membrane connector 4 also needs to pass through the insulation layer, which will weaken the insulation effect of the insulation layer and cause cold leakage channels in the sealed insulation tank.

[0077] In this embodiment, the sealing membrane is a primary sealing membrane 11, and the insulation layer is a primary insulation layer 21. The sealed insulation tank includes, in the thickness direction from the outside to the inside of the sealed insulation tank: a secondary insulation layer 22 fixed to the support structure; a secondary sealing membrane 12 carried by the secondary insulation layer 22; a primary insulation layer 21 carried by the secondary sealing membrane 12; and a primary sealing membrane 11 carried by the primary insulation layer 21 and used for contact with liquefied gas.

[0078] In this embodiment, the sealing membrane connector 4 includes a first connecting part 41 and a second connecting part 42. The first connecting part 41 is fixedly connected to the support structure, and the sealing membrane is sealed to the upper surface of the second connecting part 42. The dimension of the first connecting part 41 in the direction perpendicular to the wall thickness is larger than the dimension of the second connecting part 42 in the direction perpendicular to the wall thickness, so that the height of the sealing membrane connected to the second connecting part 42 is lower than or equal to the height of the upper surface of the first connecting part 41.

[0079] By designing the sealing membrane connector 4 as two connecting parts with a size difference, the first connecting part 41 is fixedly connected to the support structure and bears the pressure from the upper cover 3 or the insulation box, and the second part is welded to the sealing membrane. This can protect the welded part of the sealing membrane from the pressure or impact from above, prevent damage to the welded part, and enhance the stability of the sealing membrane.

[0080] Specifically, the difference between the dimension of the first connecting part 41 in the direction perpendicular to the wall thickness and the dimension of the second connecting part 42 in the direction perpendicular to the wall thickness is determined according to the thickness of the sealing film; in this embodiment, the difference between the dimension of the first connecting part 41 in the direction perpendicular to the wall thickness and the dimension of the second connecting part 42 in the direction perpendicular to the wall thickness is 1.5 mm to 2 mm; the dimension of the second connecting part 42 in the direction perpendicular to the wall thickness is 10 mm to 200 mm.

[0081] In one optional embodiment, the end-bent connecting portion 5 is partially connected to the upper surface of the second connecting portion 42; the insulation layer includes an end insulation module 6 disposed below the sealing membrane connector 4; the size of the overlapping area between the end-bent connecting portion 5 and the second connecting portion 42 is determined based on the dimensions of the sealing membrane connector 4, the end-bent connecting portion 5, and the end insulation module 6 in the wall thickness direction. Specifically, the size of the overlapping area is the sum of the dimensions of the sealing membrane connector 4 and the end-bent connecting portion 5 in the wall thickness direction minus the dimension of the end insulation module 6 in the wall thickness direction. In actual construction, other construction factors, such as the thickness of the adhesive strip that bonds the end insulation module 6 to the supporting wall, must also be considered.

[0082] Both the end bend connection 5 and the second connection 42 have sufficient welding area, and partial welding of the two can meet the welding strength requirements. In the actual assembly process of the sealed heat insulation tank, the actual size and installation position of the sealing membrane connector 4, the end bend connection 5 and the end heat insulation module 6 may have errors. The end bend connection 5 can be adjusted and partially welded to the second connection 42 according to the actual assembly situation, providing sufficient redundancy for construction.

[0083] In one optional embodiment, the sealed heat insulation tank includes a compensating support plate 7 disposed above the end heat insulation module 6; the upper surface of the compensating support plate 7 and the upper surface of the second connecting portion 42 are located on the same horizontal plane. By providing the compensating support plate 7, the dimensional difference between the end heat insulation module 6 and the end heat insulation module 6 is compensated, ensuring that the end bent connecting portion 5 can be installed on a horizontal plane.

[0084] In addition, the sealed heat-insulating tank includes a flexible covering layer that fills the gap between the sealing membrane and the cover 3. By filling the gap between the sealing membrane and the cover 3 with the flexible covering layer, the welded part of the sealing membrane can be protected from pressure or impact from above, preventing damage to the welded part, enhancing the stability of the sealing membrane, and also ensuring the flatness of the upper surface of the sealing membrane connector 4.

[0085] In this embodiment, the sealing membrane connector 4 is a primary sealing membrane connector; the sealed heat insulation tank also includes a secondary sealing membrane connector extending in the wall thickness direction; the secondary sealing membrane 12 is fixed to the supporting structure at the interruption point by the secondary sealing membrane connector; the primary sealing membrane connector and the secondary sealing membrane connector are connected by reinforcing wing plates. Furthermore, the secondary sealing membrane connector and the upper supporting wall can also be connected by reinforcing wing plates. Since the dome is generally subjected to large forces, the reinforcing wing plates can strengthen the sealing membrane connector 4, making it less prone to deformation.

[0086] The primary / secondary sealing membrane comprises multiple corrugated metal plates arranged in a repeating pattern and welded together in a sealing manner. The metal plates of the primary / secondary sealing membrane 12 are made of stainless steel. This embodiment does not limit the corrugation orientation of the primary / secondary sealing membrane. Preferably, the corrugations of the primary sealing membrane 11 face inwards from the tank, and the corrugations of the secondary sealing membrane 12 face outwards from the tank. With this arrangement, the corrugations of the primary sealing membrane 11 facing inwards from the tank can better withstand the impact force of the liquefied gas inside the tank, while the corrugations of the secondary sealing membrane 12 facing outwards from the tank can effectively reduce gas flow on the outer side of the corrugations of the secondary sealing membrane 12, thereby improving the overall thermal insulation performance of the cryogenic liquefied gas system.

[0087] In addition, such as Figure 4 As shown, the corrugated plate of the secondary sealing membrane 12 can also be a special type of corrugated plate; the corrugated plate of the secondary sealing membrane 12 includes a main body portion 111 and an edge portion 112 surrounding the main body portion 111. The edge portion 112 is used to connect with the edge portion 112 of another corrugated plate. The corrugations have protrusions 121 and recesses 122. The recesses 122 are provided on the main body portion 111, and the protrusions 121 are provided on the edge portion 112. The protrusions 121 are used to connect with the protrusions 121 of another corrugated metal plate. By providing protrusions 121 and recesses 122 in the direction perpendicular to the wall thickness of the corrugated portion of the corrugated plate, and connecting the protrusions 121 and recesses 122 through a torsion, the originally continuous circulation channel in the corrugated portion is blocked by the torsion structure at the "convex-concave" joint, thereby disrupting the conditions for stable convection of gas in the long continuous channel. This inhibits heat transfer and improves the thermal insulation performance of the cryogenic liquefied gas system.

[0088] In one embodiment, each of the intersecting corrugations of the corrugated metal plate includes at least one protrusion 121 and at least one adjacent recess 122 in its direction of extension perpendicular to the wall thickness, rather than a single continuous protrusion or recess. Specifically, each corrugation also includes a torsion 140 located at the junction of the protrusion 121 and the recess 122, for connecting the protrusion 121 and the recess 122 together in the direction of extension perpendicular to the wall thickness of the third and fourth corrugations, respectively. The protrusion 121 protrudes towards the interior of the cryogenic liquefied gas system relative to the flat area of ​​the corrugated plate, while the recess 122 is recessed away from the interior of the cryogenic liquefied gas system relative to the flat area of ​​the corrugated plate. It should be noted that both "protrusion" and "recess" are relative to the interior of the cryogenic liquefied gas system; "protrusion" means extending in a direction towards the interior of the cryogenic liquefied gas system, and "recess" means extending in a direction towards the exterior of the cryogenic liquefied gas system. This concave-convex design brings significant technical benefits. It breaks the limitation of the traditional corrugated plate having a single shape of corrugations along its entire length. By setting protrusions 121, recesses 122, and torsional parts 140 connecting the two in the direction of the corrugations extending perpendicular to the wall thickness, the originally continuous channel is blocked by the "concave-convex" structure, i.e., the torsional part 140. This disrupts the conditions for stable convection of gas in a long continuous channel, which inhibits heat transfer, improves the thermal insulation performance of the cryogenic liquefied gas system, effectively reduces LNG evaporation in the cryogenic liquefied gas system, and reduces cargo loss.

[0089] Example 2

[0090] This embodiment also provides a ship, including a hull 8 and a sealed, insulated tank 9 for storing liquefied gas disposed in the hull 8 as described above.

[0091] refer to Figure 5 A cross-sectional view of a vessel used for transporting liquefied refrigerated products shows a typically prismatic sealed insulated tank 9 mounted within a double hull 8 of the vessel. The walls of the sealed insulated tank 9 may include a primary sealing membrane for contact with the LNG contained within the tank, a secondary sealing membrane disposed between the primary sealing membrane and the vessel hull, and two insulating layers disposed between the primary and secondary sealing membranes, respectively, and between the secondary sealing membrane and the hull. Furthermore, a device / unloading pipe located on the upper deck of the vessel can be connected via suitable connectors to an offshore or port terminal to transfer LNG between the cargo ship and the tank.

[0092] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A sealed and insulated tank for storing liquefied gas, the sealed and insulated tank being arranged in a support structure, the sealed and insulated tank including a plurality of tank walls connected to each other and fixed to the support structure, the plurality of tank walls including at least one sealing membrane and at least one insulation layer, the insulation layer being disposed between the sealing membrane and the support structure; The support structure includes an upper support wall (1); the upper support wall (1), the sealing membrane, and the insulation layer are partially interrupted to define a loading and unloading opening (2), the loading and unloading opening (2) for allowing a liquefied gas loading and unloading pipeline to pass through the loading and unloading opening (2), and the tank includes a cover (3) disposed in the loading and unloading opening (2); characterized in that, The sealing membrane includes an end bend connection (5) at the interruption, which is fixed to the support structure by the upper or lower surface of the sealing membrane connector (4) extending in the wall thickness direction.

2. The sealed and insulated tank for storing liquefied gas according to claim 1, characterized in that, The sealing membrane connector (4) includes a first connecting part (41) and a second connecting part (42). The first connecting part (41) is fixedly connected to the support structure, and the sealing membrane is sealed to the upper surface of the second connecting part (42). The first connecting part (41) has a larger dimension in the direction perpendicular to the wall thickness than the second connecting part (42) in the direction perpendicular to the wall thickness, so that the height of the sealing film connected to the second connecting part (42) is lower than or equal to the height of the upper surface of the first connecting part (41).

3. The sealed and insulated tank for storing liquefied gas according to claim 2, characterized in that, The end bend connecting part (5) is partially connected to the upper surface of the second connecting part (42); The insulation layer includes an end insulation module (6) disposed below the sealing membrane connector (4); The size of the overlapping area between the end bend connection (5) and the second connection (42) is determined based on the dimensions of the sealing membrane connector (4), the end bend connection (5), and the end insulation module (6) in the wall thickness direction.

4. The sealed and insulated tank for storing liquefied gas according to claim 3, characterized in that, The sealed heat insulation tank includes a compensation support plate (7) disposed above the end heat insulation module (6); The upper surface of the compensation support plate (7) and the upper surface of the second connecting part (42) are located on the same horizontal plane.

5. The sealed and insulated tank for storing liquefied gas according to claim 2, characterized in that, The difference between the dimension of the first connecting portion (41) in the direction perpendicular to the wall thickness and the dimension of the second connecting portion (42) in the direction perpendicular to the wall thickness is determined according to the thickness of the sealing film; and / or, The difference between the dimension of the first connecting portion (41) in the direction perpendicular to the wall thickness and the dimension of the second connecting portion (42) in the direction perpendicular to the wall thickness is 1.5 mm to 2 mm; and / or, The second connecting part (42) has a dimension of 10 mm to 200 mm in the wall thickness direction.

6. The sealed and insulated tank for storing liquefied gas according to claim 1, characterized in that, The sealed heat-insulating tank includes a flexible covering layer that fills the gap between the sealing film and the covering (3).

7. The sealed and insulated tank for storing liquefied gas according to claim 1, characterized in that, The sealing membrane is a primary sealing membrane (11), and the insulation layer is a primary insulation layer (21). The sealed insulation tank includes, in the thickness direction from the outside to the inside of the sealed insulation tank: a secondary insulation layer (22) fixed to the support structure; a secondary sealing membrane (12) carried by the secondary insulation layer (22); the primary insulation layer (21) carried by the secondary sealing membrane (12); and the primary sealing membrane (11) carried by the primary insulation layer (21) and used for contact with the liquefied gas.

8. The sealed and insulated tank for storing liquefied gas according to claim 7, characterized in that, The sealing membrane connector is a primary sealing membrane connector; the sealed heat insulation tank also includes a secondary sealing membrane connector extending in the wall thickness direction; The secondary sealing membrane (12) is fixed to the support structure at the interruption point by the secondary sealing membrane connector; The primary sealing membrane connector and the secondary sealing membrane connector are connected by a reinforcing wing plate.

9. The sealed and insulated tank for storing liquefied gas according to claim 7, characterized in that, The primary sealing membrane and the secondary sealing membrane each comprise a plurality of corrugated metal plates juxtaposed in a repeating pattern and welded together in a sealing manner. The metal plates of the primary and secondary sealing membranes are made of stainless steel; and / or, The corrugations of the primary sealing membrane (11) face inwards towards the inside of the tank; and / or, The corrugations of the secondary sealing membrane (12) face outwards from the tank; and / or, The corrugated plate of the secondary sealing membrane (12) includes a main body portion (111) and an edge portion (112) disposed around the main body portion (111). The edge portion (112) is used to connect with the edge portion (112) of another corrugated plate. The corrugation has a protrusion (121) and a recess (122). The recess (122) is disposed on the main body portion (111), and the protrusion (121) is disposed on the edge portion (112). The protrusion (121) is used to connect with the protrusion (121) of another corrugated metal plate.

10. A ship for transporting liquefied gases, characterized in that, The vessel includes a hull and a sealed, insulated tank for storing liquefied gas as described in any one of claims 1 to 9 disposed within the hull.

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