CN119267778B - Low-temperature storage tank and mounting structure and mounting method of dihedral angle region of low-temperature storage tank - Google Patents
Low-temperature storage tank and mounting structure and mounting method of dihedral angle region of low-temperature storage tank Download PDFInfo
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- CN119267778B CN119267778B CN202411805946.5A CN202411805946A CN119267778B CN 119267778 B CN119267778 B CN 119267778B CN 202411805946 A CN202411805946 A CN 202411805946A CN 119267778 B CN119267778 B CN 119267778B
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Abstract
本发明公开了一种低温储罐及其二面角区域的安装结构与安装方法，涉及液化气体储存容器技术领域，包含一体式安装组件；一体式安装组件为二面角的折角形，在二面角的任一侧包含上层金属板与下层金属板，上层金属板与下层金属板通过支撑部一体连接；下层金属板内侧还一体连接一筋板；筋板与下层金属板的连接线经过二面角的两侧，并与二面角的交线相交；上层金属板与储罐底面/壁面的主层金属薄膜板焊接；下层金属板与储罐底面/壁面的次层金属薄膜板焊接。通过将上层与下层金属板一体连接，并在折角处设置了高度接近于主层的筋板，使筋板分担折角区域大部分应力，保护了上层金属板的折角区域。
The present invention discloses a low-temperature storage tank and an installation structure and an installation method for a dihedral area thereof, which relate to the technical field of liquefied gas storage containers, and include an integrated installation assembly; the integrated installation assembly is in the shape of a dihedral angle, and includes an upper metal plate and a lower metal plate on either side of the dihedral angle, and the upper metal plate and the lower metal plate are integrally connected through a support portion; a rib plate is also integrally connected to the inner side of the lower metal plate; the connection line between the rib plate and the lower metal plate passes through both sides of the dihedral angle and intersects with the intersection line of the dihedral angle; the upper metal plate is welded to the main metal film plate of the bottom/wall of the storage tank; the lower metal plate is welded to the secondary metal film plate of the bottom/wall of the storage tank. By integrally connecting the upper and lower metal plates, and providing a rib plate with a height close to the main layer at the angle, the rib plate shares most of the stress in the angle area, and protects the angle area of the upper metal plate.
Description
Technical Field
The invention relates to the technical field of liquefied gas storage containers, in particular to a low-temperature storage tank, a mounting structure and a mounting method of a dihedral angle region of the low-temperature storage tank.
Background
The wall of the low-temperature film storage container is of a multi-layer structure and comprises an insulating layer, a shielding layer and the like. At present, for each layer of fixing structure, not only axial pulling force is needed to be provided, but also larger lateral force is needed to be provided, the stud fixing form is relatively easy to cope with the axial pulling force generated by cold shrinkage, but is difficult to cope with larger lateral stress, and a screw rod for fixing an insulating layer is easy to break. In particular, for liquefied gas carrier vessels, the external environment is more complex and unstable than land storage tanks, and the requirements for mechanical properties are higher. Therefore, in the specific design of the main layer and the secondary layer, the thickness of the main layer is reduced as much as possible, and the thickness of the secondary layer is increased.
The invention patent application publication No. CN118623202A discloses a mounting structure of a corner region of a low-temperature storage tank, but the corner region of an upper layer metal plate of the structure is subjected to larger stress and is easy to fatigue under the low temperature below minus 163 ℃ through inspection.
It is therefore desirable to provide a means for securing the layers of the corner regions of the thin film storage container to increase the structural strength of the layers of the corner regions of the thin film storage container, particularly the corner regions of the primary barrier layer.
Disclosure of Invention
The invention aims to fix layers in the folded corner area of a thin film storage container and improve the structural strength of the dihedral corner area of a main shielding layer.
The invention provides a mounting structure of a dihedral angle region of a low-temperature storage tank, which comprises an integrated mounting assembly, wherein the integrated mounting assembly is a dihedral angle, any side of the dihedral angle comprises an upper layer metal plate and a lower layer metal plate, the upper layer metal plate and the lower layer metal plate on each side are integrally connected through a supporting part, a rib plate is integrally connected to the inner side of the lower layer metal plate, a connecting line of the rib plate and the lower layer metal plate passes through two sides of the dihedral angle and intersects with an intersecting line of the dihedral angle, the distance between the edge of the rib plate far away from the lower layer metal plate and the upper layer metal plate is 0.2-5 mm, the upper layer metal plate is welded with a main layer metal film plate on the bottom surface/wall surface of the storage tank to form a main shielding layer, and the lower layer metal plate is welded with a sub-layer metal film plate on the bottom surface/wall surface of the storage tank to form a sub-shielding layer.
Preferably, the support portion height is within 50 mm.
Preferably, the plane of the rib plate is perpendicular to the intersection line of the dihedral angles.
Preferably, the rib plate is directly connected with the supporting part and integrally connected with the supporting part, or is indirectly connected with the supporting part only through the lower layer metal plate.
Preferably, the rib plate and the central surface of the supporting part in the thickness direction are the same plane or parallel to each other.
Preferably, the other area between the upper metal plate and the lower metal plate is filled with a first insulating layer, and the first insulating layer is made of soft heat insulation materials.
Preferably, the area of the lower metal plate is larger than that of the upper metal plate, and the edge of the lower metal plate is arranged outside the upper metal plate.
Preferably, the thicknesses of the upper layer metal plate, the lower layer metal plate, the rib plates and the supporting parts are all 5-15 mm.
Preferably, either side of the dihedral angle of each of the integral mounting assemblies comprises at least two of the support portions and two of the gusset portions, respectively.
The invention also discloses a mounting method of the mounting structure of the dihedral angle region of the low-temperature storage tank, which comprises the following steps:
S1, manufacturing the integrated mounting assembly through welding or integrated forming, wherein the inner side of a lower metal plate of the integrated mounting assembly is also integrally connected with a rib plate;
S2, fixedly connecting the lower metal plate with a second insulating layer outside the lower metal plate;
S3, the lower metal plate is welded with a sub-layer metal film plate on the bottom surface/wall surface of the storage tank to form a sub-shielding layer;
s4, paving a plywood on the sub-layer metal film plate;
And S5, welding the upper metal plate with a main metal film plate on the bottom surface/wall surface of the storage tank to form a main shielding layer.
The invention also discloses a storage tank applying the corner region installation structure, and the storage tank can be used for storing or transporting liquefied gas on a liquefied gas carrier or on land.
The beneficial effects of the invention include:
Through with upper metal sheet and lower floor's metal sheet body coupling to set up the gusset that highly is close to main shielding layer and secondary shielding layer in dog-ear department, make gusset can share dog-ear region most stress, protected the dog-ear region of upper metal sheet.
The upper metal plate and the lower metal plate are integrally connected, so that the integral installation assembly used by the invention is beneficial to reducing the field installation time, the welding workload is less, and the secondary shielding layer, the main insulating layer and the main shielding layer in the bevel area can be installed only once.
The upper layer metal plate and the lower layer metal plate are in a stepped shape, so that layered welding is facilitated, and two independent closed spaces are formed.
Drawings
FIG. 1 is a schematic view of one embodiment of a mounting structure for a dihedral region of a cryogenic tank of the present invention;
FIG. 2 is a schematic view of another embodiment of the mounting structure of the dihedral region of the cryogenic tank of the present invention;
FIG. 3 is a schematic view of the mounting structure of the dihedral region of the cryogenic tank and other region locations of the tank floor/wall surface according to the present invention;
FIG. 4 is a section A-A of FIGS. 1 and 2;
fig. 5 is a sectional view of fig. 1 and 2 at B-B.
The reference numerals comprise 1-upper layer metal plate, 2-lower layer metal plate, 3-supporting part, 4-rib plate, 5-main layer metal film plate, 6-plywood, 7-sub layer metal film plate, 8-second insulating layer and 9-first insulating layer.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "front", "rear", "inner", "outer", "top", "bottom", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. Note that the thickness direction of the upper metal plate 1 and the lower metal plate 2 is different from the thickness direction of the support portion 3 and the rib plate 4. The thickness direction of the support portion 3 and the rib plate 4 is not shown in fig. 1 to 3, but is shown in fig. 4 and 5, that is, in the left-right direction of fig. 4 and 5.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not intended to be limiting with respect to time sequence, number, or importance, but are not to be construed as indicating or implying a relative importance or implicitly indicating the number of features indicated, but merely for distinguishing one feature from another in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly specified otherwise. Likewise, the appearances of the phrase "a" or "an" in this document are not meant to be limiting, but rather describing features that have not been apparent from the foregoing. Likewise, unless a particular quantity of a noun is to be construed as encompassing both the singular and the plural, both the singular and the plural may be included in this disclosure. Likewise, modifiers similar to "about" and "approximately" appearing before a number in this document generally include the number, and their specific meaning should be understood in conjunction with the context.
In the description of the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, directly connected, indirectly connected via an intermediate medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art. The term "integrally connected" includes welded or integrally formed connections.
Each aspect or embodiment defined herein may be combined with any other aspect or embodiment unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.
The invention discloses a mounting structure of a dihedral region of a cryogenic storage tank, which comprises an integrated mounting assembly as shown in fig. 1 to 5. The integral mounting assembly forms a main shielding layer, a main insulating layer and a secondary shielding layer in the corner area of the thin film storage tank. Therefore, the integral installation component is a folded angle, any side of the folded angle comprises the upper layer metal plate 1 and the lower layer metal plate 2, the upper layer metal plate 1 and the lower layer metal plate 2 on each side are integrally connected through the supporting part 3, and the upper layer metal plate 1, the supporting part 3 and the lower layer metal plate 2 are the same in material. Because each part in the tank can shrink under the low-temperature environment, the stress condition in the tank can be complicated due to different shrink coefficients of each part and the like. The integrated connection of the upper metal plate 1 and the lower metal plate 2 is realized, the strength of the film structure is improved, and the low-temperature deformation resistance of the film storage tank is improved.
In some embodiments, a first insulating layer 9 is filled between the upper metal plate 1 and the lower metal plate 2. The first insulating layer 9 is made of soft heat insulating material such as glass wool or polyurethane, and is different from the plywood 6 laid between the main layer metal film plate 5 and the secondary layer metal film plate 7. Because the main layer metal film plate 5 and the secondary layer metal film plate 7 are made of corrugated plates or strip alloy steel with the thickness of (1-2) mm, the plywood 6 is needed below the main layer metal film plate 5 to provide enough supporting strength, the supporting effect is achieved on the upper layer metal plate 1, and the heat insulation effect of the wood plywood is better. The upper metal plate 1 and the lower metal plate 2 in the dihedral angle region are generally made of 5-15 mm thick steel plates, so as to better cope with the stress formed during cold shrinkage in the dihedral angle region. On the other hand, the thick steel plate without paving the hard plywood is beneficial to reserving a certain space to deform the thick steel plate in the dihedral angle area, so that the tank body is prevented from being damaged due to overlarge stress in the dihedral angle area.
In some embodiments, the thickness of the first insulating layer 9 and the height of the supporting portion 3 are both within 50 mm. In this case, the distance between the upper metal plate 1 and the lower metal plate 2 is short, so that the stress applied to the upper metal plate 1, the support portion 3, and the lower metal plate 2 can be reduced, and on the other hand, the upper metal plate 1 and the lower metal plate 2 are integrally connected by the support portion 3, so that the conduction cooling capacity is conducted from the support portion 3 to the lower metal plate 2, and the cooling effect of the first insulating layer 9 is reduced. Therefore, compared with the thickness of the main insulating layer which is 200mm or more in general, the thickness of the first insulating layer 9 is intentionally reduced, and the second insulating layer 8 is thickened, so that the second insulating layer 8 mainly plays a role of heat insulation.
As shown in figures 1-5, the inner side of the lower metal plate 2 is also integrally connected with a rib plate 4, the connecting line of the rib plate 4 and the lower metal plate 2 passes through two sides of a dihedral angle and intersects with the intersection line of the dihedral angle, the rib plate 4 also forms a folded angle, the distance between the edge of the rib plate 4, which is far away from the lower metal plate 2, and the upper metal plate 1 is 0.2-5 mm, and the larger the area of the rib plate 4 is, more stress in the dihedral angle area can be shared, so that the stress applied to the folded angle of the upper metal plate 1 is reduced, and the purpose of protecting the upper metal plate 1 is better achieved. The minimum distance of 0.2mm is to prevent the rib plate 4 from contacting the upper metal plate 1, resulting in unnecessary stress.
In some embodiments, the plane of the rib plate 4 is perpendicular to the dihedral intersection line, so that the dihedral region is more uniformly stressed.
In some embodiments, as shown in fig. 1, the rib plate 4 is directly connected to the support part 3 and integrally connected thereto. Or as shown in fig. 2 and 3, the rib plate 4 and the supporting part 3 are indirectly connected only through the lower metal plate 2.
In some embodiments, as shown in fig. 1, the rib 4 and the central surface of the supporting portion 3 in the thickness direction are the same plane. Or as shown in fig. 2 and 3, the central planes of the rib plates 4 and the supporting parts 3 in the thickness direction are the same plane or parallel to each other, so that the stress on the upper layer metal plate 1, the supporting parts 3 and the rib plates 4 is uniformly distributed.
In some embodiments, the thicknesses of the rib plate 4 and the supporting portion 3 are 5-15 mm, so that the rib plate 4 and the supporting portion 3 can bear stress. Further, as shown in fig. 4 and 5, the rib plate 4 has the same thickness as the support portion 3.
The upper metal plate 1 is welded with a main metal film plate 5 on the bottom surface/wall surface of the storage tank to form a main shielding layer, the main shielding layer is directly contacted with low-temperature liquid, and the lower metal plate 2 is welded with a sub-metal film plate 7 on the bottom surface/wall surface of the storage tank to form a sub-shielding layer.
In some embodiments, the area of the lower metal plate 2 is larger than that of the upper metal plate 1, and the edge of the lower metal plate 2 is outside the upper metal plate 1, so that enough space is left for welding the lower metal plate 2 and the sub-metal film plate 7 on the bottom/wall of the tank for welding. If a first insulating layer 9 is provided between the upper metal plate 1 and the lower metal plate 2, the area of the lower metal plate 2 is larger than that of the first insulating layer 9, and the edge of the lower metal plate 2 is outside the first insulating layer 9.
In some embodiments, either side of the dihedral angle of each of the integral mounting assemblies comprises at least two of the support portions 3 and two of the rib plates 4, respectively. The purpose of the integrated mounting assembly is to enable the integrated mounting assembly to be stable when being stressed, and the integrated mounting assembly is not inclined to one side and unbalanced because only one supporting part 3 and one rib plate 4 are arranged.
The outer side of the lower metal plate 2 is provided with a second insulating layer 8. The lower metal plate 2 is connected with the second insulating layer 8 by an anchor screw.
The invention also discloses a mounting method of the mounting structure of the dihedral angle region of the low-temperature storage tank, which comprises the following steps:
s1, manufacturing the integral mounting assembly by welding or integral molding, and then assembling the integral mounting assembly in some embodiments, filling the first insulating layer 9 between the upper metal plate 1 and the lower metal plate 2;
s2, fixedly connecting the lower metal plate 2 with a second insulating layer 8 outside the lower metal plate 2, so that the integral mounting assembly is mounted on the second insulating layer 8;
S3, the lower metal plate 2 is welded with a sub-layer metal film plate 7 on the bottom surface/wall surface of the storage tank to form a sub-shielding layer;
S4, paving a plywood on the sub-layer metal film plate 7;
and S5, welding the upper metal plate 1 with the main metal film plate 5 on the bottom surface/wall surface of the storage tank to form a main shielding layer.
The invention also discloses a storage tank applying the dihedral angle region mounting structure, and the storage tank can be used for storing or transporting liquefied gas on a liquefied gas carrier or on land.
In summary, according to the invention, the upper layer metal plate and the lower layer metal plate are integrally connected, and the rib plates close to the main layer are arranged at the folded angle, so that the rib plates can share most of stress in the folded angle area, and the folded angle area of the upper layer metal plate is protected. In addition, through integrally connecting the upper metal plate and the lower metal plate, the integral installation assembly used by the invention is beneficial to reducing the field installation time, has less welding workload, and can install the secondary shielding layer, the main insulating layer and the main shielding layer in the folded angle area only once. The upper layer metal plate and the lower layer metal plate are in a stepped shape, so that layered welding is facilitated, and two independent closed spaces are formed.
While the present invention has been described in detail through the foregoing description of the preferred embodiment, it should be understood that the foregoing description is not to be considered as limiting the invention. Many modifications and substitutions of the present invention will become apparent to those of ordinary skill in the art upon reading the foregoing. Accordingly, the scope of the invention should be limited only by the attached claims.
Claims (10)
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202411805946.5A CN119267778B (en) | 2024-12-10 | 2024-12-10 | Low-temperature storage tank and mounting structure and mounting method of dihedral angle region of low-temperature storage tank |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202411805946.5A CN119267778B (en) | 2024-12-10 | 2024-12-10 | Low-temperature storage tank and mounting structure and mounting method of dihedral angle region of low-temperature storage tank |
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| CN119267778A CN119267778A (en) | 2025-01-07 |
| CN119267778B true CN119267778B (en) | 2025-03-11 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114568030A (en) * | 2019-10-18 | 2022-05-31 | 气体运输技术公司 | Sealed and thermally insulated tank |
| CN118623202A (en) * | 2024-07-02 | 2024-09-10 | 中太能源科技(上海)有限公司 | A mounting structure and method for the corner area of a cryogenic storage tank |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR3004509B1 (en) * | 2013-04-12 | 2016-11-25 | Gaztransport Et Technigaz | ANGLE STRUCTURE OF A SEALED AND THERMALLY INSULATING STORAGE OF A FLUID |
| FR3038690B1 (en) * | 2015-07-06 | 2018-01-05 | Gaztransport Et Technigaz | THERMALLY INSULATING, WATERPROOF TANK WITH SECONDARY SEALING MEMBRANE EQUIPPED WITH ANGLE ARRANGEMENT WITH WALL-MOLDED METAL SHEETS |
| KR102535971B1 (en) * | 2016-11-30 | 2023-05-24 | 대우조선해양 주식회사 | Insulation system of membraine type storage tank and membrain type storage tank |
| FR3073271B1 (en) * | 2017-11-06 | 2019-11-01 | Gaztransport Et Technigaz | SEALED AND THERMALLY INSULATED TANK |
| WO2020193653A1 (en) * | 2019-03-26 | 2020-10-01 | Gaztransport Et Technigaz | Storage facility for liquefied gas |
| CN116710356A (en) * | 2021-04-08 | 2023-09-05 | 现代重工业株式会社 | Liquefied gas storage tank and ship comprising same |
| KR20240033384A (en) * | 2022-09-05 | 2024-03-12 | 한화오션 주식회사 | Corner structure of liquefied gas insulation system |
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- 2024-12-10 CN CN202411805946.5A patent/CN119267778B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114568030A (en) * | 2019-10-18 | 2022-05-31 | 气体运输技术公司 | Sealed and thermally insulated tank |
| CN118623202A (en) * | 2024-07-02 | 2024-09-10 | 中太能源科技(上海)有限公司 | A mounting structure and method for the corner area of a cryogenic storage tank |
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| CN119267778A (en) | 2025-01-07 |
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