Sealing film, tank body and manufacturing method of low-temperature liquefied gas sealed insulation storage tank

By designing a sealing membrane structure with staggered primary and secondary protrusions and filled with low-temperature elastic glue in the cryogenic liquefied gas storage tank, the problem of sealing membrane damage caused by swaying and temperature changes in the floating structure of the tank on water is solved, and higher sealing and load-bearing capacity are achieved.

CN117190057BActive Publication Date: 2025-09-12HUDONG ZHONGHUA SHIPBUILDINGGROUP +1
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Patent Information

Application Number
CN202311175861.9
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2023-09-12
Publication Date
2025-09-12
Estimated Expiration
2043-09-12

AI Technical Summary

Technical Problem

The existing low-temperature liquefied gas storage tanks in floating structures on water suffer damage to the sealing membrane due to sloshing motion, resulting in leakage of liquefied gas. In addition, the sealing membrane lacks sufficient displacement margin and load-bearing capacity when exposed to temperature changes.

Method used

A sealing membrane for a sealed and insulated storage tank is designed. The membrane is made of multiple welded units that are orthogonally spliced ​​at 90 degrees. Each unit includes a flat portion and a raised portion. The main raised portion and the secondary raised portion are arranged alternately. The height of the main raised portion is not less than that of the secondary raised portion. Low-temperature elastic glue is filled between the welded units. The formed tank body can reduce temperature stress when exposed to cold or heat and provide a large displacement margin.

Benefits of technology

It effectively reduces the risk of damage to the sealing membrane during sloshing and temperature changes, enhances the bearing capacity of the sealing membrane, prevents tank function failure, and ensures the safe storage and transportation of liquefied gas.

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Abstract

An embodiment of the present invention provides a sealing film, a tank body and a manufacturing method for a sealed insulated storage tank for storing and transporting cryogenic liquefied gas. The metal plates included in the sealing film include a plurality of welding units that are orthogonally spliced ​​at 90 degrees and connected by sealing welding and are arranged in a rectangular shape. Each welding unit includes a planar portion and a convex portion including a main convex portion and a secondary convex portion. The main convex portion includes a transverse long strip convex portion and a longitudinal long strip convex portion that are arranged in a cross shape and divide the upper surface of the welding unit into four sub-planar portions. The longitudinal long strip convex portion includes two sides respectively provided with the transverse long strip convex portion, and each planar portion is provided with a secondary convex portion. The four secondary convex portions are spliced ​​together to form a closed regular polygon or circle; the spacing between the secondary convex portion and the nearest main convex portion is at least the width dimension of a transverse long strip convex portion, and the height dimension of the secondary convex portion is not greater than the height of the main convex portion.
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Description

Technical Field

[0001] The present invention relates to the technical field of sealed and insulated storage tanks for storing and transporting cryogenic liquefied gas, and in particular to a sealing film, a tank body and a method for manufacturing the sealing film of a sealed and insulated storage tank for storing and transporting cryogenic liquefied gas. Background Art

[0002] Chinese patent No. CN114144611A discloses a sealed and thermally insulated tank for storing LNG or LPG, which includes an auxiliary thermal insulation shield, an auxiliary sealing membrane resting on the auxiliary thermal insulation shield, a main thermal insulation shield resting on the auxiliary sealing membrane, and a main sealing membrane resting on the main thermal insulation shield and intended to be in contact with the liquefied gas, wherein the main sealing membrane is composed of a single or multiple protrusions in the shape of a sphere, an ellipsoid, and a polyhedron.

[0003] When such a tank is installed on a floating structure, the liquefied gas within the tank will experience sloshing motion when exposed to sea conditions or wind. Sloshing motion is the fluctuation of the free surface of the liquid, causing nonlinear, random movement of the liquid within the tank. This sloshing liquid typically impacts the tank, and this impact stress can adversely affect the sealing membrane and tank wall. Damage to the sealing membrane or tank wall due to impact can cause the sealing membrane to lose its functionality, ultimately leading to leakage of the liquefied gas.

[0004] Therefore, when cryogenic storage tanks are used in liquid cargo tanks of LNG ships, LPG ships, etc., the sealing membrane inside the cargo tank needs to have sufficient displacement margin when exposed to cold or heat, and the sealing membrane should have sufficient bearing capacity to resist sloshing pressure. Summary of the Invention

[0005] In view of the above-mentioned problems existing in the prior art, an embodiment of the present invention provides a sealing membrane, a tank body and a manufacturing method for a sealed insulated storage tank for storing and transporting low-temperature liquefied gas, wherein the sealed insulated storage tank is used to transport liquefied natural gas at a temperature between -163°C and -80°C or liquefied petroleum gas at a temperature between -50°C and 0°C. These tanks can be placed on land or installed on a water structure (ship or marine engineering structure). When installed on a water structure, the liquefied gas stored and transported by the tank can be used as fuel to propel the operation of the structure itself, which reduces the risk of sloshing impact damaging the tank body sealing membrane and increases the displacement margin of the sealing membrane for expansion and contraction.

[0006] An embodiment of the present invention provides a sealing membrane for a cryogenic liquefied gas sealed insulated storage tank, the sealing membrane comprising at least one metal plate, each of which comprises a plurality of rectangularly arranged welding units that are orthogonally spliced ​​at 90 degrees and fixedly connected by sealing welding, wherein:

[0007] Each of the welding units includes a planar portion and a raised portion, wherein the raised portion includes a main raised portion and a secondary raised portion, wherein the main raised portion includes a transverse long raised portion and a longitudinal long raised portion arranged in a cross shape on the upper surface of the welding unit and dividing the upper surface of the welding unit into four sub-planar portions, wherein the longitudinal long raised portion includes longitudinal sub-long raised portions respectively arranged on both sides of the transverse long raised portion and not intersecting with the transverse long raised portion, and each of the four sub-planar portions is provided with the secondary raised portion, and when the welding units corresponding to the four secondary raised portions are orthogonally spliced ​​at 90 degrees, the four secondary raised portions form a closed regular polygon or circle;

[0008] In which, the spacing between the secondary protrusion and the closest main protrusion is at least the width dimension of one of the transverse long protrusions, the spacing between the transverse long protrusion and any of the longitudinal sub-strip protrusions is at least half the width dimension of the transverse long protrusion, and the height dimension of the secondary protrusion is not greater than the height of the main protrusion.

[0009] In some embodiments of the present invention, both ends of the transverse long strip protrusion are ellipsoidal, and both ends of the longitudinal sub-long strip protrusion are ellipsoidal.

[0010] In some embodiments of the present invention, the cross-sectional shape of the main protrusion includes a top arc, a connecting area arc connected to both ends of the top arc, and a transition area arc respectively connected to the connecting area arc, and the connected arcs are all connected in a tangent and smooth manner, wherein:

[0011] The top circular arc and the connecting area circular arc are both curves with continuous curvature, and one end of the transition area circular arc away from the connecting area circular arc connected thereto is tangent to the plane portion.

[0012] In some embodiments of the present invention, the width dimension of the transverse long protrusion is the dimension between the arc of the transition area of ​​the cross-sectional curve shape of the transverse long protrusion in the width direction and the tangent point of the planar portion.

[0013] In some embodiments of the present invention, the height dimension of the cross section of the main protrusion is represented by H, and is 38 mm ≤ H ≤ 78 mm;

[0014] The radius of the top arc is represented by R1, the radius of the connecting area arc is represented by R2, and the radius of the transition area arc is represented by R3, and the following conditions are met:

[0015] 0.8≤R1:R3≤1.2;

[0016] 5≤R2:R3≤6;

[0017] R2:H≤4.

[0018] In some embodiments of the present invention, the height dimension of the cross section of the main protrusion is represented by H, and is 40 mm ≤ H ≤ 100 mm;

[0019] The top arc and the connecting area arc of the cross-sectional shape of the main protrusion satisfy the parabola shape expressed by the following formula, specifically,

[0020]

[0021] The transition area arc is tangent to the parabola, and the radius of the transition area arc is represented by R3 and satisfies the condition of R3=0.2H.

[0022] In some embodiments of the present invention, the height dimension of the cross section of the main protrusion is represented by H, and is 30 mm ≤ H ≤ 80 mm;

[0023] The top arc and the connecting area arc of the cross-sectional shape of the main protrusion satisfy the elliptical shape expressed by the following formula, specifically,

[0024] Among them, 1 / 3≤a / H≤5 / 8;

[0025] The transition area arc is tangent to the ellipse of the first quadrant and the second quadrant of the ellipse, and meets the requirement of 0.1≤R3:H≤0.3,

[0026] Wherein, R3 represents the radius of the arc of the transition area.

[0027] In some embodiments of the present invention, each metal plate has a length of at least 1.2 m in the longitudinal direction and a length of at least 0.6 m in the transverse direction;

[0028] The plate welding unit has a thickness ranging from 1 mm to 1.8 mm and is made of a metal material with a yield strength ranging from 170 MPa to 500 MPa.

[0029] An embodiment of the present invention further provides a tank body using the sealing film of the cryogenic liquefied gas sealed insulation storage tank described in the above embodiment, the tank body comprising:

[0030] The tank wall, which encloses the interior space of the tank and is in contact with the cryogenic liquefied gas;

[0031] an insulating structure attached to the tank wall, wherein the insulating structure has the sealing film provided on a surface away from the tank wall;

[0032] Wherein, low-temperature elastic glue is filled between the secondary convex portion of the sealing film and the insulating structure, and the low-temperature elastic glue after solidification does not adhere to the sealing film and the insulating structure.

[0033] The embodiment of the present invention further provides a method for manufacturing a sealing film for a cryogenic liquefied gas sealed insulated storage tank as described in the above embodiment, characterized in that the method comprises the following steps:

[0034] Step 1: According to the structural design drawing of the sealing membrane corresponding to the sealing membrane of the cryogenic liquefied gas sealed insulation storage tank described in the above embodiment, a corresponding stamping die is produced, and the metal plate is cut into rectangular metal plates of the required size;

[0035] Step 2: placing the manufactured stamping die and the cut rectangular metal plate together in a stamping machine for forming to obtain a welding unit having the shape of the flat portion and the convex portion of the sealing film;

[0036] Step 3: Assemble the stamped welding units, specifically arranging adjacent welding units at 90 degrees orthogonally to form the shape of the metal plate required for the sealing film, and then weld and fix the welding units by sealing welding to form a metal plate;

[0037] Step 4: According to the principle of butting the raised portions of adjacent metal plates, the metal plates are welded together by lap welding to form a complete sealing membrane.

[0038] Compared with the prior art, the sealing film, tank body and manufacturing method of the sealed insulated storage tank for storing and transporting cryogenic liquefied gas provided by the embodiment of the present invention have the following beneficial effects: by arranging the main protrusions of the welding unit protrusions in a crisscross manner on the plane area, and arranging the secondary protrusions evenly on the plane area, the temperature stress generated in the plane area with low continuity when exposed to cold or heat is greatly reduced. On the other hand, the protrusions also provide a large displacement margin. Furthermore, by setting the height of the main protrusion to be no less than the height of the secondary protrusion, the protrusions of different shapes can more evenly bear the pressure caused by the sloshing of the liquid in the tank through the different height arrangements, effectively avoiding damage to the sealing film and preventing the failure of the storage tank function. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic top view of a first structure of a sealing membrane for a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0040] Figure 2 A schematic structural diagram of a welding unit corresponding to a first structure of a sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0041] Figure 3 A schematic top view of a second structure of a sealing membrane for a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0042] Figure 4 A schematic structural diagram of a welding unit corresponding to the second structure of the sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0043] Figure 5 A schematic top view of a third structure of a sealing membrane for a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0044] Figure 6 A schematic structural diagram of a welding unit corresponding to the third structure of the sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0045] Figure 7 A schematic cross-sectional view of a secondary raised portion of a welding unit corresponding to the third structure of the sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0046] Figure 8 The sealing film of the cryogenic liquefied gas sealed insulation storage tank provided by the embodiment of the present invention is used Figure 7 Schematic cross-sectional view of a planar portion of a sealing membrane arranged by adding corresponding secondary protrusions as shown in ;

[0047] Figure 9 A schematic diagram of the cross-sectional line shape of the main protrusion of the welding unit corresponding to the first structure of the sealing membrane of the cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0048] Figure 10 A schematic diagram showing a first cross-sectional line shape for a main protrusion of a welding unit of a sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0049] Figure 11 A schematic diagram showing a second cross-sectional line shape for a main protrusion of a welding unit of a sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0050] Figure 12 A schematic diagram showing a third cross-sectional line shape for a main protrusion of a welding unit of a sealing membrane of a cryogenic liquefied gas sealed insulated storage tank provided by an embodiment of the present invention;

[0051] Figure 13 A schematic structural diagram of a tank body provided in an embodiment of the present invention.

[0052] Reference numerals

[0053] 1. Welding unit; 2. Plane portion; 3. Main raised portion; 4. Secondary raised portion; 5. Horizontal long raised portion; 6. Longitudinal long raised portion; 7. Cross section of main raised portion; 8. Top arc; 9. Connection area arc; 10. Transition area arc; 11. Insulation structure; 12. Low-temperature elastic adhesive; 13. Plywood. DETAILED DESCRIPTION

[0054] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0055] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] The embodiment of the present invention provides a sealing film for a cryogenic liquefied gas sealed insulation storage tank, such as Figures 1 to 12As shown, the sealing film includes at least one metal plate, each of which includes a plurality of welding units 1 that are orthogonally spliced ​​at 90 degrees and fixedly connected in a sealed welding manner and arranged in a rectangular shape, wherein each of the welding units 1 includes a plane portion 2 and a raised portion, and the raised portion includes a main raised portion 3 and a secondary raised portion 4. The main raised portion 3 includes a transverse long raised portion 5 and a longitudinal long raised portion 6 that are arranged in a cross shape on the upper surface of the welding unit 1 and divide the upper surface of the welding unit 1 into four sub-plane portions, and the longitudinal long raised portion 6 includes longitudinal sub-long raised portions that are respectively arranged on both sides of the transverse long raised portion 5 and do not intersect with the transverse long raised portion 5. Each of the four sub-plane parts is provided with a secondary protrusion 4. After the welding units 1 corresponding to the four secondary protrusions 4 are orthogonally spliced ​​at 90 degrees, the four secondary protrusions 4 form a closed regular polygon or a circle; wherein, the protrusions in the main protrusion 3 and the secondary protrusion 4 are spaced apart from each other and are not connected to each other, and the spacing between the secondary protrusion 4 and the nearest main protrusion 3 is at least the width dimension of one of the transverse long strip protrusions 5, and the spacing between the transverse long strip protrusion 5 and any of the longitudinal sub-strip protrusions is at least half the width dimension of the transverse long strip protrusion 5, and the height dimension of the secondary protrusion 4 is not greater than the height of the main protrusion 3. Furthermore, the secondary protrusions 4 are distributed on the planar portion 2 of the welding unit 1 and are symmetrical about the center point of the welding unit 1. The width dimension of the main protrusion 3 is the dimension between the tangent points of the arc of the cross-sectional curve shape of the main protrusion 3 in the width direction and the planar portion 2. At the same time, after the welding units 1 are spliced, the four welding units 1 can be surrounded by the transverse long protrusions 5 and the longitudinal long protrusions 6 to form a planar area that is approximately an equilateral rectangle, and the secondary protrusions 4 are evenly distributed in the center of the planar area; in addition, each main protrusion 3 and each secondary protrusion 4 has at least one axially symmetrical plane.

[0062] In the above embodiment, if Figure 2 、 Figure 4 and Figure 6Three embodiments of the welding unit 1 are respectively shown. The welding unit 1 is symmetrical along the middle longitudinal plane and the middle transverse section, but not centrally symmetrical. The metal plate is welded by the welding unit 1 in a sealed welding manner. Since the welding unit 1 is not centrally symmetrical, it has two directions of placement: front and side during welding. In the process of making the metal plate, a plurality of rectangular welding units 1 are orthogonally spliced ​​at 90 degrees. Specifically, when two welding units 1 are placed side by side in the same direction, when one welding unit 1 is spliced ​​with another welding unit 1, the welding unit 1 is first rotated 90 degrees with the center line perpendicular to itself as the center of the circle, and then the side of the welding unit 1 after rotating 90 degrees is spliced ​​with the side of the other welding unit 1, that is, the spliced ​​sides of the two welding units 1 are perpendicular to each other when the two welding units 1 are placed side by side in the same direction. In this embodiment, each metal plate is at least 1.2 meters long in the longitudinal direction and at least 0.6 meters long in the transverse direction. For example, the metal plate may be 2.4 meters long in the longitudinal direction and 1.2 meters long in the transverse direction. Furthermore, the welding unit 1 has a thickness between 1 mm and 1.8 mm and is made of a metal material having a yield strength between 170 MPa and 500 MPa, specifically stainless steel or high-manganese steel.

[0063] Furthermore, in the above embodiment, both ends of the transverse long strip raised portion 5 are ellipsoidally arranged, and both ends of the longitudinal sub-long strip raised portion are ellipsoidally arranged, so that both ends of the transverse long strip raised portion 5 and both ends of the longitudinal sub-long strip raised portion can bear force better.

[0064] Meanwhile, in the above embodiment, if Figure 9 As shown, the cross-sectional shape of the main protrusion 3 includes a top arc 8, a connecting area arc 9 connected to both ends of the top arc 8, and a transition area arc 10 respectively connected to the connecting area arc 9. The connected arcs are connected in a tangent and smooth manner, so that the top shape of the cross section 7 of the main protrusion is a curve with continuous curvature, wherein the top arc 8 and the connecting area arc 9 are both curves with continuous curvature, and the transition area arc 10 is tangent to the plane part 2 at one end away from the connecting area arc 9 connected thereto.

[0065] In the above embodiment, the width dimension of the transverse long protrusion 5 is the dimension between the tangent point of the transition area arc 10 of the cross-sectional curve shape of the transverse long protrusion 5 in the width direction and the plane portion 2 .

[0066] In this embodiment, if Figure 10As shown, the height dimension of the shape formed by the cross-section 7 of the main convex part is represented by H, and 38 mm ≤ H ≤ 78 mm; the top of the shape of the cross-section 7 of the main convex part is composed of two arcs tangent to each other, specifically including a top arc 8, a connecting area arc 9 connected to both ends of the top arc 8, and a transition area arc 10 respectively connected to the connecting area arc 9. The arcs connected to each other are all connected in a tangent and smooth connection manner. The radius of the top arc 8 is represented by R1, the radius of the connecting area arc 9 is represented by R2, and the radius of the transition area arc 10 is represented by R3. Among them, R1 < R2, and R1, R2, and R3 satisfy the following conditions:

[0067] 0.8 ≤ R1:R3 ≤ 1.2;

[0068] 5 ≤ R2:R3 ≤ 6;

[0069] R2:H ≤ 4;

[0070] As an example, the height dimension H of the shape formed by the cross-section 7 of the main convex part can be set to 44 mm, the radius R1 of the top arc 8 can be set to 10 mm, the radius R2 of the connecting area arc 9 can be set to 46 mm, and the radius R3 of the transition area arc 10 can be set to 10 mm.

[0071] In some embodiments of the present invention, as Figure 11 shown, the height dimension of the shape formed by the cross-section 7 of the main convex part is still represented by H, and 40 mm ≤ H ≤ 100 mm;

[0072] The top arc 8 and the connecting area arc 9 of the cross-section shape of the main convex part 3 satisfy the parabolic shape represented by the following formula. Specifically,

[0073]

[0074] The transition area arc 10 of the cross-section shape of the main convex part 3 is tangent to the parabola, and the radius of the transition area arc 10 is represented by R3, and satisfies the condition of R3 = 0.2H;

[0075] As an example, the height dimension H of the shape formed by the cross-section of the main convex part 3 is H = 43 mm, and the radius R3 of the transition area arc 10 is R3 = 10 mm.

[0076] In addition, in some embodiments of the present invention, as Figure 12 shown, the height dimension of the shape formed by the cross-section of the main convex part is still represented by H, and 30 mm ≤ H ≤ 80 mm;

[0077] The top arc 8 and the connecting area arc 9 of the cross-sectional shape of the main protrusion 3 satisfy the elliptical shape expressed by the following formula, specifically,

[0078] Among them, 1 / 3≤a / H≤5 / 8;

[0079] The transition area arc 10 of the cross-sectional shape of the main protrusion 3 is tangent to the ellipse of the first quadrant and the second quadrant of the ellipse and meets the requirement of 0.1≤R3:H≤0.3, where R3 represents the radius of the transition area arc 10;

[0080] As an example, Figure 12 As shown, the height dimension H of the shape formed by the cross section of the main protrusion 3 is 40 mm, the short radius a of the ellipse is 20 mm, and the radius R3 of the transition area arc 10 is 8.4 mm.

[0081] In some embodiments of the present invention, see Figures 1 to 2 As shown, the secondary protrusion 4 can have a similar cross-sectional shape to the main protrusion 3, and the secondary protrusion 4 can be a ring-shaped secondary protrusion 4 obtained by rotating the protrusion cross section 360° with the center of the plane portion 2 as the rotation center. Of course, the secondary protrusion 4 can also be a ring-shaped secondary protrusion 4 obtained by rotating the protrusion cross section 360° with the center of the sub-plane portion where the secondary protrusion 4 is located as the rotation center. There is at least one spacing between the secondary protrusions 4 equal to the width dimension of the secondary protrusion 4. The width dimension of the secondary protrusion 4 is the dimension between the tangent points of the arc of the cross-sectional curve shape of the secondary protrusion 4 in the width direction and the plane portion 2. In addition, in this embodiment, the secondary protrusion 4 can also be intermittent, that is, the secondary protrusion 4 is arranged in an intermittent structure, and the two ends of each section of the secondary protrusion 4 can be arranged in an ellipsoidal shape.

[0082] In some embodiments of the present invention, when the secondary protrusion 4 can have a similar cross-sectional shape to the primary protrusion 3, the secondary protrusion 4 can also be arranged in the form of a single protrusion located in the center of the sub-plane portion where it is located. The secondary protrusion 4 has a similar cross-sectional shape to the primary protrusion 3, and the shape curve is used as a slice to sweep and stretch along the shape of an equilateral rectangle to obtain a rectangular secondary protrusion 4. For details, please refer to Figure 3 and Figure 4 In addition, in this embodiment, the secondary protrusion 4 can also be intermittently arranged, that is, the secondary protrusion 4 is arranged in an intermittent structure, and both ends of the secondary protrusion 4 of each section can be arranged in an ellipsoidal shape.

[0083] Furthermore, in some embodiments of the present invention, Figure 5 and Figure 6As shown, while the arrangement of the primary protrusion 3 is the same as in the previous embodiment, the secondary protrusion 4 can also be a spherical protrusion on the sub-plane portion where it is located. The secondary protrusion 4 can be arranged in two ways, depending on the protrusion width. For example, a single secondary protrusion 4 can be arranged at the center of the sub-plane portion where it is located, or multiple secondary protrusions can be evenly distributed on the sub-plane portion where they are located. In the design process of cryogenic storage tanks, the sealing membrane located at the bottom or top of the cryogenic tank is usually designed as a metal plate with multiple protrusions. This measure is more beneficial to the structural safety of the tank sealing membrane.

[0084] As can be seen from the above technical solution, the sealing membrane provided by the above embodiment of the present invention arranges the main protrusions 3 of the raised portion of the welding unit 1 in a crisscross pattern on the planar area, and the secondary protrusions 4 are evenly arranged on the planar area. This greatly reduces the temperature stress generated in the planar area with low continuity when exposed to heat and cold. On the other hand, the protrusions also provide a large displacement margin. Furthermore, by setting the height of the main protrusion 3 to be no less than the height of the secondary protrusion 4, the protrusions of different shapes can more evenly bear the pressure caused by the sloshing of the liquid in the tank through the different height arrangements, effectively avoiding damage to the sealing membrane and preventing tank failure.

[0085] The present invention also provides a tank body using the sealing film of the cryogenic liquefied gas sealed insulation storage tank described in the above embodiment. Figure 13 As shown, the tank body can be used as a sealed and insulated storage tank for storing and transporting LNG, and the tank body includes:

[0086] The tank wall, which encloses the interior space of the tank and is in contact with the cryogenic liquefied gas;

[0087] An insulating structure 11 is attached to the tank wall. The insulating structure 11 has the sealing film disposed on a surface away from the tank wall. Specifically, the sealing film comprises at least one metal plate, and each metal plate comprises a plurality of rectangular welding units 1 that are orthogonally joined at 90 degrees and fixedly connected by sealing welding. The welding units 1 include a flat portion 2 and a raised portion.

[0088] The space between the secondary raised portion 4 of the raised portion of the sealing film and the insulating structure 11 is filled with low-temperature elastic glue 12 , and the solidified low-temperature elastic glue 12 does not adhere to the sealing film and the insulating structure 11 .

[0089] In this embodiment, the structures of the tank body from the inside to the outside include a sealing film, a low-temperature elastic glue 12 (flexible low-temperature glue), a main insulating structure in the insulating structure 11, a secondary insulating structure in the insulating structure 11, and an outer wall. Furthermore, plywood 13 or a structure similar to plywood can be arranged between the low-temperature elastic glue 12 and the main insulating structure, and between the secondary insulating structure and the outer wall.

[0090] By filling the low-temperature elastic glue 12 between the secondary raised portion 4 of the sealing film and the insulating structure 11, the low-temperature glue after solidification can play a certain supporting and reinforcing role, and can enable the raised portion to maintain a certain displacement margin to prevent structural damage. The low-temperature glue can be in direct contact with the sealing film and the insulating structure 11, but not adhere to each other, thereby preventing additional deformation stress from being applied to the low-temperature glue during low-temperature shrinkage.

[0091] With these features, the height of the primary protrusions 3 and the spacing and dimensions of the secondary protrusions 4 allow the raised portion to withstand sloshing impacts relatively evenly, without experiencing excessive sloshing. Furthermore, the regular distribution of the secondary protrusions 4 and the support provided by the low-temperature adhesive effectively and evenly distribute and withstand sloshing impact loads, thereby effectively preventing damage to the sealing membrane and ensuring the membrane's tightness.

[0092] The tank body using the sealing membrane of the cryogenic liquefied gas sealed insulation storage tank can be used as an onshore storage tank or an offshore structure storage tank, for example, for onshore LNG storage, or installed on an offshore structure, particularly a cryogenic liquefied gas carrier, a deep-water transport vessel, or an above-water or underwater floating (production) storage unit. The tank body can also be used as a fuel storage tank in an above-water or underwater floating structure.

[0093] At the same time, an embodiment of the present invention also provides a method for manufacturing a sealing film for a cryogenic liquefied gas sealed insulated storage tank as described in the above embodiment, the method comprising the following steps:

[0094] Step 1: According to the structural design drawing of the sealing membrane corresponding to the sealing membrane of the cryogenic liquefied gas sealed insulation storage tank described in the above embodiment, a corresponding stamping die is produced, and the metal plate is cut into rectangular metal plates of the required size;

[0095] Step 2: placing the manufactured stamping die and the cut rectangular metal plate together in a stamping machine for forming to obtain a welding unit 1 having the shape of the flat portion 2 and the convex portion of the sealing film;

[0096] Step 3: Assemble the stamped welding units 1, specifically arranging adjacent welding units 1 at 90 degrees orthogonally to form the shape of the metal plate required for the sealing film, and then weld and fix the welding units 1 by sealing welding to form a metal plate;

[0097] The aspect ratio of the metal plate required for the sealing film may be 2:1.

[0098] Step 4: According to the principle of butting the raised portions of adjacent metal plates, the metal plates are welded together by lap welding to form a complete sealing membrane.

[0099] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the scope of the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the spirit and scope of protection of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the scope of protection of the present invention.

Claims

1. A sealing film for a cryogenic liquefied gas sealed insulation storage tank, characterized in that: The sealing film comprises at least one metal plate, each of which comprises a plurality of rectangular welding units which are orthogonally spliced ​​at 90 degrees and fixedly connected by sealing welding, wherein: Each of the welding units includes a planar portion and a raised portion, wherein the raised portion includes a main raised portion and a secondary raised portion, wherein the main raised portion includes a transverse long raised portion and a longitudinal long raised portion arranged in a cross shape on the upper surface of the welding unit and dividing the upper surface of the welding unit into four sub-planar portions, and the longitudinal long raised portion includes longitudinal sub-long raised portions respectively arranged on both sides of the transverse long raised portion and not intersecting with the transverse long raised portion, and each of the four sub-planar portions is provided with a secondary raised portion, and when the welding units corresponding to the four secondary raised portions are orthogonally spliced ​​at 90 degrees, the four secondary raised portions form a closed regular polygon or circle; In which, the spacing between the secondary protrusion and the closest main protrusion is at least the width dimension of one of the transverse long protrusions, the spacing between the transverse long protrusion and any of the longitudinal sub-long protrusions is at least half the width dimension of the transverse long protrusion, and the height dimension of the secondary protrusion is not greater than the height of the main protrusion.

2. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 1, characterized in that: Both ends of the transverse long strip raised portion are arranged in an ellipsoidal shape, and both ends of the longitudinal sub-long strip raised portion are arranged in an ellipsoidal shape.

3. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 1, characterized in that: The cross-sectional shape of the main protrusion includes a top arc, a connecting area arc connected to both ends of the top arc, and a transition area arc respectively connected to the connecting area arc, and the connected arcs are all connected in a tangent and smooth manner, wherein: The top circular arc and the connecting area circular arc are both curves with continuous curvature, and one end of the transition area circular arc away from the connecting area circular arc connected thereto is tangent to the plane portion.

4. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 3, characterized in that: The width dimension of the transverse long protrusion is the dimension between the arc of the transition area of ​​the cross-sectional curve shape of the transverse long protrusion in the width direction and the tangent point of the plane part.

5. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 3, characterized in that: The height dimension of the cross section of the main protrusion is represented by H and is 38mm≤H≤78mm; The radius of the top arc is represented by R1, the radius of the connecting area arc is represented by R2, and the radius of the transition area arc is represented by R3, and the following conditions are met: 0.8≤R1:R3≤1.2; 5≤R2:R3≤6; R2:H≤4.

6. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 3, characterized in that: The height dimension of the cross section of the main protrusion is represented by H, and is 40mm≤H≤100mm; The top arc and the connecting area arc of the cross-sectional shape of the main protrusion satisfy the parabola shape expressed by the following formula, specifically, The transition area arc is tangent to the parabola, and the radius of the transition area arc is represented by R3 and satisfies the condition of R3=0.2H.

7. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 3, characterized in that: The height dimension of the cross section of the main protrusion is represented by H, and is 30mm≤H≤80mm; The top arc and the connecting area arc of the cross-sectional shape of the main protrusion satisfy the elliptical shape expressed by the following formula, specifically, Among them, 1 / 3≤a / H≤5 / 8; The transition area arc is tangent to the ellipse of the first quadrant and the second quadrant of the ellipse, and meets the requirement of 0.1≤R3:H≤0.3, Wherein, R3 represents the radius of the arc of the transition area.

8. The sealing film of the cryogenic liquefied gas sealed insulation storage tank according to claim 1, characterized in that: Each metal plate has a length of at least 1.2 m in the longitudinal direction and a length of at least 0.6 m in the transverse direction; The welding unit has a thickness ranging from 1 mm to 1.8 mm and is made of a metal material with a yield strength ranging from 170 MPa to 500 MPa.

9. A tank body using the sealing film of a cryogenic liquefied gas sealed insulation storage tank according to any one of claims 1 to 8, characterized in that: The tank body comprises: The tank wall, which encloses the interior space of the tank and is in contact with the cryogenic liquefied gas; an insulating structure attached to the tank wall, wherein the insulating structure has the sealing film provided on a surface away from the tank wall; Wherein, low-temperature elastic glue is filled between the secondary convex portion of the sealing film and the insulating structure, and the low-temperature elastic glue after solidification does not adhere to the sealing film and the insulating structure.

10. A method for manufacturing a sealing film for a sealed insulated storage tank for cryogenic liquefied gas according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: Step 1: According to the structural design drawing of the sealing film corresponding to the sealing film of the cryogenic liquefied gas sealed insulated storage tank as described in any one of claims 1 to 8, a corresponding stamping die is manufactured, and the metal plate is cut into rectangular metal plates of the required size; Step 2: placing the manufactured stamping die and the cut rectangular metal plate together in a stamping machine for forming to obtain a welding unit having the shape of the flat portion and the convex portion of the sealing film; Step 3: Assemble the stamped welding units, specifically arranging adjacent welding units at 90 degrees orthogonally to form the shape of the metal plate required for the sealing film, and then weld and fix the welding units by sealing welding to form a metal plate; Step 4: According to the principle of butting the raised portions of adjacent metal plates, the metal plates are welded together by lap welding to form a complete sealing membrane.

Citation Information

Patent Citations

  • Sealing membrane for sealed fluid storage tank

    CN114144611A

  • Polygonal corrugated plate suitable for thin film tank containment system and thin film tank

    CN115789502A

  • Membraine corrugation struture for law temperatur liquid tank

    KR1019980067005A