Multi-hull tanks and ships
The proposed piping structure in multi-shell tanks concentrates pipe penetrations in outer and inner tank projections, improving workability and maintainability by ensuring airtight and heat-insulated passages, thus preventing fluid leakage into non-refrigerated spaces.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- KAWASAKI JUKOGYO KK
- Filing Date
- 2021-03-31
- Publication Date
- 2026-06-24
AI Technical Summary
Existing multi-shell tanks face challenges with dispersed pipe penetrations that increase manufacturing time, inspection points, and reduce accessibility and maintainability, particularly when handling flammable or cryogenic fluids.
A piping structure is proposed where pipe penetrations are concentrated in outer and inner tank projections, ensuring airtight and heat-insulated passages through refrigerated spaces without traversing other tank spaces, thereby consolidating maintenance points and preventing fluid leakage.
This configuration enhances workability, maintainability, and accessibility by concentrating pipe penetrations, while preventing fluid leakage into non-refrigerated spaces, especially when dealing with flammable gases.
Smart Images
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Abstract
Description
Technical Field
[0005] , ,
[0001] The present disclosure relates to a multi-shell tank and a ship equipped with the same, and more particularly to a piping structure passed between adjacent tanks of the multi-shell tank.
Background Art
[0002] Conventionally, a multi-shell tank for storing low-temperature liquefied gas and a ship equipped with the same are known. Patent Document 1 discloses this type of multi-shell tank.
[0003] The multi-shell tank (liquid gas storage device) of Patent Document 1 includes a tank for storing liquid gas, an inner shell covering the tank, and an outer shell covering the inner shell. The cold insulation space between the tank and the inner shell is filled with vaporized gas obtained by vaporizing the liquid gas. The space between the inner shell and the outer shell is filled with nitrogen gas. A dome for passing a pipeline for loading and unloading the liquid gas is provided at the top of the tank. The dome is provided with an evaporation gas pipe for guiding the vaporized gas evaporated in the tank to a heater, and the vaporized gas heated by the heater is supplied to the cold insulation space through a supply pipe.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] As described in Patent Document 1, a multi-shell tank consisting of multiple tanks (shells) may be equipped with piping that runs between tanks and extends to the outside of the multi-shell tank in order to supply gas between tanks or discharge gas from between tanks. When such piping carries flammable or cryogenic fluids, it is desirable that it be laid so as not to pass through other tank spaces located outside the tank space through which the piping passes, in order to prevent leakage at joints or other points. In Patent Document 1, a projection is provided in the inner shell that penetrates the outer shell and protrudes outwards, and the supply pipe passes through this projection, thereby entering the refrigerated space without passing through other tank spaces located on the outside. However, this projection of the inner shell is located away from the dome where the tank's piping is concentrated.
[0006] The parts of a tank through which piping penetrates (hereinafter referred to as pipe penetrations) require reinforcement and strength evaluation. Furthermore, if the tank is insulated, special heat-insulating construction is required for the pipe penetrations as well. For these reasons, a smaller number of pipe penetrations is desirable, as a larger number of pipe penetrations increases the number of man-hours required in manufacturing and the number of inspection points required in maintenance. Moreover, in a multi-walled tank, if pipe penetrations are dispersed, accessibility and maintainability of valves and instruments installed in the piping are reduced, so it is desirable to concentrate the pipe penetrations in one place.
[0007] This disclosure is made in view of the above circumstances, and its purpose is to propose a piping structure in a multi-shell tank in which the pipe penetrations of the tank can be consolidated. [Means for solving the problem]
[0008] This disclosure One aspect The multi-shell tanks related to this are It comprises an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, and inter-tank piping passing between the inner tank and the outer tank. The inner tank comprises an inner tank body and an inner tank projection that extends from the inner tank body through the outermost shell and protrudes to the outside of the outermost shell. The outer tank comprises an outer tank body that covers the inner tank body, and an outer tank projection that penetrates the outermost shell, protrudes to the outside of the outermost shell, and surrounds at least a portion of the inner tank projection. The outer tank protrusion has at least a portion of the outer tank exposed to the outside of the outermost shell, The inter-tank piping is located between the inner tank body and the outer tank body. an airtight space It passes through, between the inner tank protrusion and the outer tank protrusion, and the outer tank exposed portion of the outer tank protrusion Passed through the pipe penetration provided there Extending outwards Furthermore, airtight construction is performed between the outer tank and the inter-tank piping at the pipe penetration portion. Its defining characteristic is its presence. Furthermore, a multi-shell tank according to another aspect of this disclosure is: It comprises an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, and inter-tank piping passing between the inner tank and the outer tank. The inner tank comprises an inner tank body and an inner tank projection that extends from the inner tank body through the outermost shell and protrudes to the outside of the outermost shell. The outer tank comprises an outer tank body that covers the inner tank body, and an outer tank projection that penetrates the outermost shell, protrudes to the outside of the outermost shell, and surrounds at least a portion of the inner tank projection. The outer tank protrusion has at least a portion of the outer tank exposed to the outside of the outermost shell, The inner tank protrusion has a constricted portion in the middle of the protruding direction. The outer tank protrusion is provided so as to surround the constricted portion, The inter-tank piping passes between the inner tank body and the outer tank body, between the constricted portion of the inner tank protrusion and the outer tank protrusion, and extends outward through the outer tank exposed portion of the outer tank protrusion.
[0009] Furthermore, the multi-shell tank relating to this disclosure is It comprises an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, and inter-tank piping passing between the inner tank and the outer tank. The inner tank comprises an inner tank body and an inner tank projection that extends from the inner tank body through the outer tank and the outermost shell and protrudes to the outside of the outermost shell. The outer tank has an outer tank body that covers the inner tank body, The inner tank protrusion has at least a portion of the inner tank exposed to the outside of the outermost shell, The inter-tank piping is characterized in that it passes between the inner tank body and the outer tank body, penetrates the inner tank protrusion and enters the inner tank protrusion, and extends outward through the inner tank exposed portion of the inner tank protrusion.
[0010] Furthermore, the multi-shell tank relating to this disclosure is An inner tank, an outer tank that houses the inner tank, an outermost shell that houses the inner tank and the outer tank, an inter-tank pipe that passes between the inner tank and the outer tank, and an inner-tank pipe that allows the inside of the inner tank to communicate with the outside. The inner tank has an inner-tank body. The outer tank has an outer-tank body that covers the inner-tank body and an outer-tank protrusion that penetrates the outermost shell from the outer-tank body and protrudes to the outside of the outermost shell. The outer-tank protrusion has at least a part of an outer-tank exposure part exposed outside the outermost shell. The inter-tank pipe passes between the inner-tank body and the outer-tank body, passes through the inside of the outer-tank protrusion, penetrates the outer-tank exposure part of the outer-tank protrusion, and extends outward. The inner-tank pipe penetrates the inner-tank body from inside the inner-tank body, passes through the inside of the outer-tank protrusion, penetrates the outer-tank exposure part of the outer-tank protrusion, and extends outward.
[0011] A ship according to the present disclosure includes a hull and the multi-shell tank supported by the hull.
[0012] According to the multi-shell tank having the above configuration and the ship including the same, the pipe penetration parts of the multi-shell tank are concentrated in the outer-tank protrusion and the inner-tank protrusion (or, the inner-tank protrusion or the outer-tank protrusion). By concentrating the pipe penetration parts provided in the multi-shell tank in this way, an improvement in workability during tank construction can be expected. Further, during maintenance of each pipe penetration part and valves, instruments, etc. provided in the pipes passing through the pipe penetration parts, since the pipe penetration parts are concentrated, the maintenance locations are concentrated, and thus an improvement in maintainability and accessibility can be expected.
[0013] Moreover, in the multi-shell tank having the above configuration and the ship including the same, the inter-tank pipe penetrates the outer-tank protrusion or the inner-tank protrusion and reaches the exposure, and the inter-tank pipe does not pass through the space between the outer tank and the outermost shell. Therefore, leakage of the fluid flowing through the inter-tank pipe into the space between the outer tank and the outermost shell can be prevented.
Advantages of the Invention
[0014] According to the present invention, a piping structure in a multi-shell tank can be proposed in which the pipe penetration portions of the tank can be aggregated.
Brief Description of the Drawings
[0015] [Figure 1] FIG. 1 is a schematic side view of a ship equipped with a multi-shell tank according to an embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view of a multi-shell tank to which a piping structure according to the first example is applied. [Figure 3] FIG. 3 is a schematic cross-sectional view of a multi-shell tank to which a piping structure according to the first example is applied. [Figure 4] FIG. 4 is a schematic cross-sectional view of a multi-shell tank to which a piping structure according to the second example is applied. [Figure 5] FIG. 5 is a schematic cross-sectional view of a multi-shell tank to which a piping structure according to the third example is applied. [Figure 6] FIG. 6 is a schematic cross-sectional view of a multi-shell tank to which a piping structure according to the fourth example is applied. [Figure 7] FIG. 7 is a schematic cross-sectional view of a multi-shell tank to which a piping structure according to the fifth example is applied.
Mode for Carrying Out the Invention
[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification, "inside" means the side closer to the central portion of the space inside the inner tank of the multi-shell tank, and "outside" means the side farther from the central portion of the space inside the inner tank of the multi-shell tank.
[0017] 〔Schematic Configuration of Ship 1〕 FIG. 1 is a schematic side view of a ship 1 equipped with a multi-shell tank 2 according to the present embodiment. As shown in FIG. 1, the ship 1 includes at least one multi-shell tank 2 and a hull 11 on which the multi-shell tank 2 is mounted. The ship 1 is a liquefied gas carrier that transports low-temperature liquefied gas. Examples of the liquefied gas include LNG, liquefied nitrogen, liquefied hydrogen, liquefied helium, and the like.
[0018] [Outline configuration of multi-shell tank 2] Figure 2 is a schematic cross-sectional view of a multi-hull tank 2 (2A) to which the piping structure according to the first example is applied. As shown in Figures 1 and 2, the multi-hull tank 2 comprises an inner tank 3, an outer tank 4 housing the inner tank 3, and an outermost hull 15 housing the inner tank 3 and the outer tank 4. In this embodiment, the outermost hull 15 is formed by a tank cover 12 that covers the upper part of the outer tank 4 and retaining walls 14 that cover the sides and bottom of the outer tank 4. The upper part of the outer tank 4 may be covered by a part of the hull 11 instead of the tank cover 12. The retaining walls 14 may be formed, for example, by a part of the hull 11.
[0019] In this embodiment, both the inner tank 3 and the outer tank 4 are spherical. Spherical shapes include not only perfect spheres but also capsule shapes and elliptical shapes. However, the inner tank 3 and the outer tank 4 are not necessarily limited to spherical shapes and may be rectangular.
[0020] Liquefied gas is contained in the storage space 51 inside the inner tank 3. An airtight space (hereinafter referred to as the refrigerated space 52) is formed between the inner tank 3 and the outer tank 4. Insulation material is placed in the refrigerated space 52. Furthermore, the refrigerated space 52 is filled with a gas whose boiling point is equal to or higher than the boiling point of the liquefied gas stored in the storage space 51. In this embodiment, the vaporized gas of the liquefied gas in the storage space 51 is filled in the refrigerated space 52, and this vaporized gas is flammable. Thus, when the gases filled in the storage space 51 and the refrigerated space 52 are the same, the refrigerated space 52 may be in communication with the refrigerated space 52 inside the inner tank 3.
[0021] A nearly sealed space (hereinafter referred to as the retaining space 53) is formed between the outer tank 4 and the outermost shell 15. The retaining space 53 is filled with, for example, a non-combustible or flame-retardant gas such as nitrogen gas or inert gas, or dry air. In this embodiment, the retaining space 53 is filled with nitrogen gas.
[0022] The inner tank 3 comprises an inner tank body 31 and an inner tank projection 32 that protrudes upward from the top of the inner tank body 31. The inner tank projection 32 is designed to guide piping that passes through the inside of the inner tank 3 directly to the exposure space above the tank cover 12 and to form a space that communicates with the inside of the inner tank 3, without passing through other spaces. The inner tank projection 32 has a dome shape and is generally referred to as the inner tank dome. The inner tank projection 32 includes a tubular peripheral wall rising from the inner tank body 31 and a ceiling wall that closes the upper opening of the peripheral wall. The upper part of the inner tank projection 32 protrudes above the tank cover 12 and is exposed.
[0023] The inner tank 3 is provided with a tower 20 that extends from the top of the inner tank projection 32 to the bottom of the inner tank body 31. Although not shown in the figure, a pump for pumping up liquefied gas is installed in the lower part of the tower 20. Liquid transfer pipes and electrical pipes are connected to this pump, and these liquid transfer pipes and electrical pipes pass through the inside of the tower 20, through the inner tank projection 32, and extend to the outside. However, the pump located at the bottom of the tower 20 may be omitted. The inner tank 3 is provided with at least one inner tank piping 91 that connects the inside of the inner tank 3 to the outside of the multi-shell tank 2. One end of the inner tank piping 91 opens into the inside of the inner tank 3, and the inner tank piping 91 extends to the outside, passing through the inner tank 3 (or the inner tank 3 and the outer tank 4). The inner tank piping 91 may pass through the tower 20. In Figure 2, one inner tank piping 91 is typically shown, but the multi-shell tank 2 may be provided with multiple inner tank piping 91. The internal tank piping 91 is, for example, a pneumatic pipe that guides boil-off gas, generated by the vaporization of liquefied gas in the internal tank 3, from the internal tank 3 to other equipment outside the multi-shell tank 2. Other equipment includes, for example, a propulsion engine, a power generation engine, a reliquefaction device, and an atmospheric release device. However, the internal tank piping 91 is not limited to a pneumatic pipe and may include, for example, a liquid transport pipe for cargo, sampling piping, and spray piping.
[0024] At least one inter-tank pipe 92 is passed through the refrigerated space 52 between the inner tank 3 and the outer tank 4. Although one inter-tank pipe 92 is typically shown in Figure 2, the multi-shell tank 2 may have multiple inter-tank pipes 92. The inter-tank pipe 92 may be appropriately supported by structural members arranged in the refrigerated space 52. The inter-tank pipe 92 passes between the inner tank body 31 and the outer tank body 41 and extends to the outside, penetrating at least one of the inner tank 3 and the outer tank 4. One end of the inter-tank pipe 92 may open at any position in the refrigerated space 52 between the inner tank body 31 and the outer tank body 41. The inter-tank pipe 92 may branch / combine within the refrigerated space 52. The inter-tank pipe 92 may be a liquid supply pipe, an air supply pipe, or an electrical pipe. Furthermore, if the inter-tank piping 92 is a liquid supply pipe or an air supply pipe, the inter-tank piping 92 may supply gas or liquid to the refrigerated space 52, or it may discharge gas or liquid from the refrigerated space 52. Specific examples of the inter-tank piping 92 include purging pipes, sampling pipes, air supply pipes, etc.
[0025] In the inner tank 3 and outer tank 4, the portion of the tank through which piping such as the inter-tank piping 92 penetrates is conveniently referred to as the pipe penetration section. The pipe penetration section is fitted with airtight construction to ensure airtightness between the tank and the piping. In addition, the pipe penetration section is fitted with the same heat-insulating construction as the tank.
[0026] [Piping structure] The following describes five examples of piping structures, primarily for laying inter-tank piping 92 within the multi-shell tank 2.
[0027] <Example 1 of piping structure> In the multi-shell tank 2A shown in Figure 2, the outer tank 4 has an outer tank body 41 and an outer tank projection 42 that protrudes upward from the top of the outer tank body 41. The outer tank projection 42 is designed to guide the piping that passes through the cooling space 52 between the inner tank 3 and the outer tank 4 directly to the exposure space without passing through other spaces, by protruding towards the exposure space above the tank cover 12 and forming a space that communicates with the cooling space 52.
[0028] The outer tank projection 42 is a cylindrical body that surrounds the inner tank projection 32. However, the outer tank projection 42 does not need to surround the entire circumference of the inner tank projection 32; it is sufficient if it surrounds at least a part of it. The top of the outer tank projection 42 is lower than the top of the inner tank projection 32, so the annular top of the outer tank projection 42 is visible around the top of the inner tank projection 32. The top and part of the sides (upper part) of the outer tank projection 42 form an outer tank exposed portion 43 that is exposed above the tank cover 12. However, if an outer tank exposed portion 43 can be formed on the outer tank projection 42, the height of the top of the outer tank projection 42 may be greater than or equal to the height of the top of the inner tank projection 32. Also, if the outer tank exposed portion 43 is exposed to an exposure space (atmosphere), a cover or roof may be provided around it.
[0029] The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, and between the inner tank projection 32 and the outer tank projection 42, and extends to the outside by penetrating the outer tank exposed portion 43. That is, the pipe penetration for the inter-tank piping 92 is provided in the outer tank exposed portion 43 of the outer tank projection 42. In the multi-shell tank 2A shown in Figure 2, the pipe penetration is provided in the outer tank exposed portion 43 on the side of the outer tank projection 42, but as in the multi-shell tank 2A' shown in Figure 3, the pipe penetration may be provided in the outer tank exposed portion 43 at the top of the outer tank projection 42. Figure 3 is a schematic cross-sectional view of a multi-shell tank 2A' to which the piping structure according to the first example is applied.
[0030] In the multi-shell tanks 2A and 2A' with the above configuration, pipe penetrations for inter-tank piping 92 are provided in the outer tank projection 42. The inner tank projection 32 is where pipe penetrations for piping that passes through the tower 20, including the inner tank piping 91, are concentrated. The outer tank projection 42 surrounds the side of the inner tank projection 32, and the inner tank projection 32 and the outer tank projection 42 are sufficiently close to each other. Therefore, it can be said that the pipe penetrations provided in the outer tank projection 42 and the pipe penetrations in the inner tank projection 32 are concentrated in the multi-shell tanks 2A and 2A'. In other words, the above piping structure makes it possible to consolidate multiple pipe penetrations in the multi-shell tanks 2A and 2A'. Each pipe penetration is airtight, heat-insulated, and reinforced, and then its strength is evaluated. Consolidating the pipe penetrations is expected to improve work efficiency. Furthermore, while valves and instruments installed in each pipe penetration and the piping passing through these penetrations are inspected during maintenance, consolidating the pipe penetrations concentrates the maintenance points, which is expected to improve maintainability and accessibility.
[0031] Furthermore, in the multi-shell tanks 2A and 2A' with the above configuration, the inter-tank piping 92 passes only through the refrigerated space 52 and not through the storage space 51 and the holding space 53. Therefore, even if the inter-tank piping 92 is damaged or otherwise compromised, the fluid passing through the inter-tank piping 92 may leak into the refrigerated space 52 or the exposed area, but it will not leak into the storage space 51 or the holding space 53. Thus, the above piping structure is particularly useful when the fluid passing through the inter-tank piping 92 is a flammable gas.
[0032] <Second example of piping structure> Figure 4 is a schematic cross-sectional view of a multi-shell tank 2B to which the piping structure according to the second example is applied. In the multi-shell tank 2B shown in Figure 4, the inner tank projection 32 has a constriction 33 between the base 35, which is the connection part with the inner tank body 31, and the top 36 in the vertical direction. The constriction 33 has a smaller diameter than the top 36 and base 35 of the inner tank projection 32. The constriction 33 may be provided along the entire outer circumference of the inner tank projection 32, or it may be provided at multiple locations distributed around the outer circumference of the inner tank projection 32.
[0033] The outer tank 4 has an outer tank body 41 and an outer tank projection 42 that protrudes upward from the top of the outer tank body 41. The outer tank projection 42 is cylindrical in shape and is formed to surround the constricted portion 33 of the inner tank projection 32. The outer diameter of the outer tank projection 42 is substantially the same as the outer diameter of the top 36 of the inner tank projection 32, and there is a gap between the constricted portion 33 of the inner tank projection 32 and the outer tank projection 42. However, the outer diameter of the outer tank projection 42 and the outer diameter of the top 36 of the inner tank projection 32 may be different. A part of the side of the outer tank projection 42 is an outer tank exposed portion 43 that is exposed above the tank cover 12.
[0034] The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, and between the constricted portion 33 of the inner tank projection 32 and the outer tank projection 42, and extends to the outside by penetrating the outer tank exposed portion 43 of the outer tank projection 42. The pipe penetration for the inter-tank piping 92 is provided on the outer tank exposed portion 43 on the side of the outer tank projection 42. In this way, the inter-tank piping 92 passes only through the refrigeration space 52 within the multi-layered tank 2B, and does not pass through the storage space 51 or the holding space 53.
[0035] In the multi-shell tank 2B equipped with the piping structure according to the second example, in addition to the effects and advantages of the multi-shell tanks 2A and 2A' equipped with the piping structure according to the first example, the following effects and advantages are obtained. That is, while the outer tank protrusion 42 and the inner tank protrusion 32 each have independent exposed portions, the combined volume of the outer tank protrusion 42 and the inner tank protrusion 32 can be reduced.
[0036] <Third example of piping structure> Figure 5 is a schematic cross-sectional view of a multi-shell tank 2C to which the piping structure according to the third example is applied. In the multi-shell tank 2C shown in Figure 5, the outer tank 4 has an outer tank body 41 and an outer tank projection 42 that protrudes upward from the top of the outer tank body 41. The outer tank projection 42 has a dome shape that completely encloses the inner tank projection 32. The top and part of the sides of the outer tank projection 42 are exposed outer tank portions 43 that are exposed above the tank cover 12. The outer diameter of the outer tank projection 42 is larger than the outer diameter of the inner tank projection 32, and there is a gap between the inner tank projection 32 and the outer tank projection 42.
[0037] The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, and between the inner tank projection 32 and the outer tank projection 42, and extends to the outside by penetrating the outer tank exposed portion 43 of the outer tank projection 42. The pipe penetration for the inter-tank piping 92 is provided in the outer tank exposed portion 43 of the outer tank projection 42. In Figure 5, the pipe penetration is provided in the outer tank exposed portion 43 on the side of the outer tank projection 42, but the pipe penetration may also be provided in the outer tank exposed portion 43 at the top of the outer tank projection 42. The inter-tank piping 92 passes only through the refrigeration space 52 within the multi-shell tank 2C, and does not pass through the storage space 51 or the holding space 53.
[0038] In the multi-shell tank 2C equipped with the piping structure according to the third example, in addition to the effects and advantages of the multi-shell tanks 2A, 2A equipped with the piping structure according to the first example, the following effects and advantages are obtained. Specifically, since the entire inner tank protrusion 32 is covered by the outer tank protrusion 42, a cooling layer is formed around the entire perimeter of the inner tank protrusion 32.
[0039] <Fourth example of piping structure> Figure 6 is a schematic cross-sectional view of a multi-shell tank 2D to which the piping structure according to the fourth example is applied. In the multi-shell tank 2D shown in Figure 6, the outer tank 4 has an outer tank body 41, and the outer tank body 41 and the side surface of the inner tank protrusion 32 are airtightly connected.
[0040] The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, through the inner tank protrusion 32, through the inside of the inner tank protrusion 32, and extends to the outside through the exposed portion of the inner tank protrusion 32. The pipe penetrations for the inter-tank piping 92 are provided at the portion of the inner tank protrusion 32 that is exposed to the cold space 52 and at the exposed portion of the inner tank protrusion 32. In Figure 6, the pipe penetrations are provided at the outer tank exposed portion 43 on the side of the inner tank protrusion 32, but the pipe penetrations may also be provided at the exposed portion of the top of the inner tank protrusion 32.
[0041] In the multi-shell tank 2D with the above configuration, pipe penetrations for inter-tank piping 92 are provided in the inner tank projection 32. Furthermore, pipe penetrations of piping that passes through the tower 20, including the inner tank piping 91, are concentrated in this inner tank projection 32. In this way, pipe penetrations of piping, including the inter-tank piping 92, are concentrated and arranged in the inner tank projection 32. In other words, the above piping structure makes it possible to concentrate multiple pipe penetrations of the multi-shell tank 2D. Each pipe penetration is airtight, heat-insulated, and reinforced, and then its strength is evaluated. By consolidating the pipe penetrations, improved workability can be expected. Furthermore, valves and instruments provided in each pipe penetration and in the piping that passes through the pipe penetrations are inspected during maintenance, but since the maintenance points are concentrated by consolidating the pipe penetrations, improved maintainability and accessibility can be expected.
[0042] Furthermore, in the multi-shell tank 2D with the above configuration, the inter-tank piping 92 passes through the refrigeration space 52 and the storage space 51, but not through the holding space 53. Therefore, if the inter-tank piping 92 is damaged or otherwise compromised, the fluid passing through the inter-tank piping 92 may leak into the storage space 51, the refrigeration space 52, or the exposure, but it will not leak into the holding space 53. Thus, the above piping structure is particularly useful when the fluid passing through the inter-tank piping 92 is the same as the vaporized gas of the liquefied gas contained in the storage space 51.
[0043] <Fifth example of piping structure> Figure 7 is a schematic cross-sectional view of a multi-shell tank 2E to which the piping structure according to the fifth example is applied. In the multi-shell tank 2E shown in Figure 7, the inner tank 3 has an inner tank body 31 and does not have an inner tank protrusion 32. The outer tank 4 has an outer tank body 41 and an outer tank protrusion 42 that protrudes upward from the top of the outer tank body 41. The outer tank protrusion 42 has a dome shape. The top and part of the sides of the outer tank protrusion 42 form an outer tank exposed portion 43 that is exposed to the outside of the tank cover 12.
[0044] The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, and through the inside of the outer tank projection 42, extending to the outside by penetrating the outer tank exposed portion 43 of the outer tank projection 42. In Figure 7, the pipe penetration for the inter-tank piping 92 is provided on the outer tank exposed portion 43 on the side of the outer tank projection 42, but the pipe penetration for the inter-tank piping 92 may also be provided on the outer tank exposed portion 43 at the top of the outer tank projection 42. The inter-tank piping 92 passes only through the refrigeration space 52 within the multi-layered tank 2E, and does not pass through the storage space 51 or the holding space 53.
[0045] The inner tank piping 91 passes through the inner tank body 31, through the inside of the outer tank projection 42, and extends to the outside by passing through the outer tank exposed portion 43 of the outer tank projection 42. In Figure 7, the pipe penetration for the inner tank piping 91 is provided in the outer tank exposed portion 43 at the top of the outer tank projection 42, but the pipe penetration for the inner tank piping 91 may be provided in the outer tank exposed portion 43 on the side of the outer tank projection 42. The inner tank piping 91 passes through the storage space 51 and the cooling space 52 within the multi-shell tank 2E, but does not pass through the holding space 53.
[0046] In the multi-shell tank 2E equipped with the piping structure according to the fifth example, if damage occurs to the inter-tank piping 92, the fluid passing through the inter-tank piping 92 may leak into the refrigerated space 52 or the exposed area, but it will not leak into the holding space 53. Similarly, if damage occurs to the inner tank piping 91, the fluid passing through the inner tank piping 91 may leak into the storage space 51, the refrigerated space 52, or the exposed area, but it will not leak into the holding space 53. Therefore, the above piping structure is particularly useful when the fluid filling the refrigerated space 52 is the same as the vaporized gas of the liquefied gas contained in the storage space 51.
[0047] [Summary] As described above, the multi-shell tanks 2A, 2A', 2B, and 2C having the piping structure according to the first to third examples of this embodiment include an inner tank 3, an outer tank 4 housing the inner tank 3, an outermost shell 15 housing the inner tank 3 and the outer tank 4, and inter-tank piping 92 passing between the inner tank 3 and the outer tank 4. Here, the inner tank 3 has an inner tank body 31 and an inner tank projection 32 that extends from the top of the inner tank body 31 through the outermost shell 15 and protrudes to the outside of the outermost shell 15. The outer tank 4 has an outer tank body 41 that covers the inner tank body 31 and an outer tank projection 42 that extends from the top of the outer tank body 41 through the outermost shell 15 and protrudes to the outside of the outermost shell 15 and surrounds at least a portion of the inner tank projection 32, and the outer tank projection 42 has at least a portion of an exposed outer tank exposed portion 43. The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, between the inner tank protrusion 32 and the outer tank protrusion 42, and extends outward through the outer tank exposed portion 43 of the outer tank protrusion 42.
[0048] In these multi-shell tanks 2A, 2A', 2B, and 2C, the pipe penetrations for the inter-tank piping 92 are provided on the outer tank exposed portion 43 of the outer tank projection 42. The outer tank projection 42 surrounds the inner tank projection 32, where the pipe penetrations of the piping passed through the inner tank 3 are concentrated, and the pipe penetrations of the inter-tank piping 92 are positioned close to the pipe penetrations of the piping passed through the inner tank 3. By consolidating the pipe penetrations in the multi-shell tanks 2A, 2A', 2B, and 2C in this way, improved workability during tank construction can be expected. Furthermore, when performing maintenance on each pipe penetration and valves, instruments, etc., provided on the piping passed through the pipe penetrations, the consolidation of pipe penetrations means that the maintenance points are concentrated, which can be expected to improve maintainability and accessibility.
[0049] Furthermore, in the multi-shell tanks 2A, 2A', 2B, and 2C with the above configuration, the inter-tank piping 92 passes only through the refrigeration space 52 and not through the storage space 51 and the holding space 53. Therefore, if the inter-tank piping 92 is damaged, the fluid passing through the inter-tank piping 92 will not leak into the storage space 51 and the holding space 53. Thus, the above piping structure is particularly useful when the fluid passing through the inter-tank piping 92 is a flammable gas, as it prevents the flammable gas from flowing into the holding space 53.
[0050] In the multi-shell tanks 2A and 2A' equipped with the piping structure described in the first example above, the inner tank projection 32 protrudes more than the outer tank projection 42, and the outer tank projection 42 has an outer tank exposed portion 43 on at least one of its top and side.
[0051] Furthermore, in the multi-shell tank 2B having the piping structure described in the second example above, the inner tank projection 32 has a constricted portion 33 in the middle of the projection direction, the outer tank projection 42 is provided so as to surround the constricted portion 33, and the inter-tank piping 92 passes between the constricted portion 33 of the inner tank projection 32 and the outer tank projection 42.
[0052] Furthermore, the multi-shell tank 2D having a piping structure according to the fourth example of this embodiment comprises an inner tank 3, an outer tank 4 housing the inner tank 3, an outermost shell 15 housing the inner tank 3 and the outer tank 4, and inter-tank piping 92 passing between the inner tank 3 and the outer tank 4. Here, the inner tank 3 has an inner tank body 31 and an inner tank projection 32 that extends from the top of the inner tank body 31 through the outer tank 4 and the outermost shell 15 and protrudes to the outside of the outermost shell 15, with the inner tank projection 32 having an exposed inner tank portion 38 in at least a part of it. The outer tank 4 has an outer tank body 41 that covers the inner tank body 31. The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, passes through the inner tank projection 32 and into the inner tank projection 32, and extends outward through the exposed inner tank portion 38 of the inner tank projection 32.
[0053] In the multi-shell tank 2D with the above configuration, pipe penetrations for inter-tank piping 92 are provided in the inner tank projection 32, so that the pipe penetrations of the piping, including the inter-tank piping 92, are concentrated in the inner tank projection 32. By consolidating the pipe penetrations in the multi-shell tank 2D in this way, improvements in workability during tank construction can be expected. Furthermore, when performing maintenance on each pipe penetration and valves, instruments, etc., provided in the piping through the pipe penetrations, the concentration of pipe penetrations means that the maintenance points are concentrated, which can be expected to improve maintainability and accessibility.
[0054] Furthermore, in the multi-shell tank 2D, the inter-tank piping 92 passes through the refrigeration space 52 and the storage space 51, but not through the holding space 53. Therefore, in the event of damage to the inter-tank piping 92, leakage of the fluid passing through the inter-tank piping 92 into the holding space 53 is prevented. Thus, if the fluid passing through the inter-tank piping 92 is the same flammable gas as the vaporized gas of the liquefied gas contained in the storage space 51, the outflow of the flammable gas into the holding space 53 can be prevented, making the above piping structure particularly useful.
[0055] Furthermore, the multi-shell tank 2E having a piping structure according to the fifth example of this embodiment comprises an inner tank 3, an outer tank 4 housing the inner tank 3, an outermost shell 15 housing the inner tank 3 and the outer tank 4, inter-tank piping 92 passing between the inner tank 3 and the outer tank 4, and inner tank piping 91 connecting the inside of the inner tank 3 to the outside. Here, the inner tank 3 has an inner tank body 31, and the outer tank 4 has an outer tank body 41 covering the inner tank body 31, and an outer tank projection 42 that extends from the outer tank body 41 through the outermost shell 15 and protrudes to the outside of the outermost shell 15, with at least a portion of the outer tank projection 42 having an outer tank exposed portion 43 exposed to the outside of the outermost shell 15. The inter-tank piping 92 passes between the inner tank body 31 and the outer tank body 41, through the inside of the outer tank protrusion 42, and extends outward through the outer tank exposed portion 43 of the outer tank protrusion 42. The inner tank piping 91 passes from inside the inner tank body 31, through the inner tank body 31, through the inside of the outer tank protrusion 42, and extends outward through the outer tank exposed portion 43 of the outer tank protrusion 42.
[0056] In the multi-shell tank 2E with the above configuration, pipe penetrations for inter-tank piping 92 and internal tank piping 91 are provided in the outer tank projection 42, so that the pipe penetrations of the piping, including the inter-tank piping 92 and internal tank piping 91, are concentrated in the outer tank projection 42. By consolidating the pipe penetrations in the multi-shell tank 2E in this way, improvements in workability during tank construction can be expected. Furthermore, when performing maintenance on each pipe penetration and valves, instruments, etc., provided in the piping through the pipe penetrations, the maintenance points are consolidated due to the concentration of pipe penetrations, thus improving maintainability and accessibility.
[0057] Furthermore, in the multi-shell tank 2E, the inter-tank piping 92 passes through the refrigerated space 52 but not through the holding space 53. Similarly, the inner tank piping 91 passes through the storage space 51 and the refrigerated space 52 but not through the holding space 53. Therefore, in the event of damage to the inter-tank piping 92 and / or the inner tank piping 91, leakage of the fluid passing through the inter-tank piping 92 and / or the inner tank piping 91 into the holding space 53 is prevented. Thus, the above piping structure is particularly useful when the fluid filling the refrigerated space 52 is the same as the vaporized gas of the liquefied gas contained in the storage space 51.
[0058] Furthermore, the vessel 1 according to this embodiment comprises a hull 11 and multi-hull tanks 2 (2A to 2E) supported by the hull 11. Liquefied gas is contained in the inner tank 3, flammable gas is filled between the inner tank 3 and the outer tank 4, and non-flammable gas, flame-retardant gas, or dry air is filled between the outer tank 4 and the outermost hull 15. In the above-described vessel 1, in the multi-hull tanks 2 (2A to 2E), leakage of the flammable gas filled between the inner tank 3 and the outer tank 4 into the space filled with non-flammable gas between the outer tank 4 and the outermost hull 15 is prevented through the inter-tank piping 92.
[0059] Although preferred embodiments of the present invention have been described above, modifications to the specific structure and / or function details of the above embodiments may also be included in the present invention without departing from the spirit of the invention. The above configuration can be modified, for example, as follows.
[0060] For example, the multi-shell tank 2 (2A to 2E) according to the above embodiment comprises two tanks, an inner tank 3 and an outer tank 4, but it may also comprise three or more tanks. In this case, the present invention can be applied by considering a pair of adjacent tanks, one inside and one outside, as the inner tank 3 and the other as the outer tank 4.
[0061] For example, the multi-shell tanks 2 (2A to 2E) according to the above embodiment are spherical (or rectangular) tanks independent of the hull 11, but they may also be membrane-type tanks that utilize the hull 11. In this case, by substituting the inner tank 3 for the membrane, the outer tank 4 for the inner shell, and the outermost shell 15 for the outer shell (hull) in the above embodiment, the present invention can be applied to a membrane-type tank.
[0062] For example, although the multi-hull tanks 2 (2A to 2E) according to the above embodiment are cargo tanks, the multi-hull tanks 2 (2A to 2E) do not necessarily have to be installed on the ship 1 as cargo tanks, and may be installed as fuel tanks. Also, the number of multi-hull tanks 2 (2A to 2E) installed on the ship 1 is not specified. [Explanation of Symbols]
[0063] 1: Ship 2,2A~2E: Multi-shell tanks 3: Inner tank 4: Outer tank 11: Hull 12: Tank cover 14: Retaining wall 15: Outermost shell 20: Tower 22: Multi-shell tank 31: Inner tank body 32: Inner tank protrusion 33: Constriction 36:Top 38: Inner tank exposure part 41: Outer tank body 42:Outer tank protrusion 43:Outer tank exposure part 51: Storage space 52: Cooling space 53: Holding space 91: Internal tank piping 92: Inter-tank piping
Claims
1. It comprises an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, and inter-tank piping passing between the inner tank and the outer tank. The inner tank comprises an inner tank body and an inner tank projection that extends from the inner tank body through the outermost shell and protrudes to the outside of the outermost shell. The outer tank comprises an outer tank body that covers the inner tank body, and an outer tank projection that penetrates the outermost shell, protrudes to the outside of the outermost shell, and surrounds at least a portion of the inner tank projection. The outer tank protrusion has at least a portion of the outer tank exposed to the outside of the outermost shell, The inter-tank piping passes through an airtight space between the inner tank body and the outer tank body, between the inner tank protrusion and the outer tank protrusion, and extends outward through a pipe penetration provided in the outer tank exposed portion of the outer tank protrusion, with airtight sealing applied between the outer tank and the inter-tank piping at the pipe penetration. Multi-shell tank.
2. The inner tank protrusion protrudes more than the outer tank protrusion, and the outer tank protrusion has the outer tank exposed portion on at least one of its top and side. A multi-shell tank according to claim 1.
3. A vessel comprising an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, and inter-tank piping passing between the inner tank and the outer tank, The inner tank comprises an inner tank body and an inner tank projection that extends from the inner tank body through the outermost shell and protrudes to the outside of the outermost shell. The outer tank comprises an outer tank body that covers the inner tank body, and an outer tank projection that penetrates the outermost shell, protrudes to the outside of the outermost shell, and surrounds at least a portion of the inner tank projection. The outer tank protrusion has at least a portion of the outer tank exposed to the outside of the outermost shell, The inner tank protrusion has a constricted portion in the middle of the protruding direction. The outer tank protrusion is provided so as to surround the constricted portion, The inter-tank piping passes between the inner tank body and the outer tank body, between the constricted portion of the inner tank protrusion and the outer tank protrusion, and extends outward through the outer tank exposed portion of the outer tank protrusion. Multi-shell tank.
4. It comprises an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, and inter-tank piping passing between the inner tank and the outer tank. The inner tank comprises an inner tank body and an inner tank projection that extends from the inner tank body through the outer tank and the outermost shell and protrudes to the outside of the outermost shell. The outer tank has an outer tank body that covers the inner tank body, The inner tank protrusion has at least a portion of the inner tank exposed to the outside of the outermost shell, The inter-tank piping passes between the inner tank body and the outer tank body, penetrates the inner tank protrusion and enters the inner tank protrusion, and extends outward through the inner tank exposed portion of the inner tank protrusion. Multi-shell tank.
5. It comprises an inner tank, an outer tank housing the inner tank, an outermost shell housing the inner tank and the outer tank, inter-tank piping running between the inner tank and the outer tank, and inner tank piping connecting the inside of the inner tank to the outside. The inner tank has an inner tank body, The outer tank comprises an outer tank body that covers the inner tank body, and an outer tank projection that extends from the outer tank body through the outermost shell and protrudes to the outside of the outermost shell. The outer tank protrusion has at least a portion of the outer tank exposed to the outside of the outermost shell, The inter-tank piping passes between the inner tank body and the outer tank body, passes inside the outer tank protrusion, penetrates the outer tank exposed portion of the outer tank protrusion, and extends outward. The inner tank piping extends from inside the inner tank body, through the inner tank body, through the inside of the outer tank projection, and through the outer tank exposed portion of the outer tank projection to the outside. Multi-shell tank.
6. The hull and, The vessel comprises a multi-hull tank according to any one of claims 1 to 5, supported by the hull, ship.
7. The inner tank contains liquefied gas, the space between the inner tank and the outer tank is filled with flammable gas, and the space between the outer tank and the outermost shell is filled with non-flammable gas, flame-retardant gas, or dry air. The vessel according to claim 6.