WO2024062621A1

WO2024062621A1 - Multi-layer tank and marine vessel

Info

Publication number: WO2024062621A1
Application number: PCT/JP2022/035478
Authority: WO
Inventors: 太一郎下田; 祐介清水; 晴彦冨永; 和宏黒田; 邦彦持田; 森田中; 正義猪原
Original assignee: 川崎重工業株式会社
Priority date: 2022-09-22
Filing date: 2022-09-22
Publication date: 2024-03-28

Abstract

This multi-layer tank comprises: an inner tank; an outer tank enclosing the inner tank; a cylindrical inner skirt extending vertically from the outer wall of the inner tank to a foundation; and a cylindrical outer skirt that is disposed on the outside in the radial direction of the inner skirt and extends vertically from the outer wall of the outer tank to the foundation. The present invention comprises: the multi-layer tank; and a marine vessel equipped with the multi-layer tank.

Description

Multi-shell tanks and ships

The present disclosure relates to a multi-shell tank and a ship equipped with the same, and specifically relates to a support structure for a multi-shell tank.

Multi-shell tanks for storing low-temperature liquefied gas have been known for some time. A multi-shell tank comprises an inner tank and an outer tank surrounding the inner tank. Some multi-shell tanks have an inner tank supported by a cylindrical support member called a skirt. Patent Document 1 discloses this type of multi-shell tank.

The multi-shell tank (double-shell cylindrical low-temperature storage tank) of Patent Document 1 includes an inner tank and an outer tank that surrounds the inner tank via a cold insulation layer, and the inner tank penetrates through the end of the bottom plate of the outer tank. The inner tank and outer tank are supported on the foundation by a cylindrical skirt that extends to the bottom. The outer tank is composed of a hemispherical outer tank roof plate, a cylindrical outer tank side plate, an outer tank body plate, and an outer tank bottom plate. The upper end of the outer tank bottom plate is connected to the inner periphery of the skirt via a ring-shaped bottom plate connection member, and the lower end of the outer tank body plate is connected to the outer periphery of the skirt via a ring-shaped body plate connection member. ing.

Japanese Patent Application Publication No. 2010-54033 (Figures 4 and 6)

In the multi-shell tank of Patent Document 1, an inner tank and an outer tank are supported by a single skirt made of a single cylinder. For example, in a multi-shell tank mounted on a moving object such as a ship, dynamic loads act on the support structure of the tank due to the movement of the moving object or the movement of a load caused by the movement of the moving object. Therefore, further strength is required for the support structure of the tank. When the support structure of the tank is a single skirt, as in the multi-shell tank of Patent Document 1, reinforcement is possible by increasing the wall thickness of the skirt, but as the wall thickness increases, processing becomes difficult. There are issues such as increased difficulty and a significant increase in cost, and there are limits to the strength that can be reinforced.

This disclosure has been made in consideration of the above circumstances, and aims to provide a structure that can improve the strength of the tank support structure in multi-shell tanks and ships equipped with them.

In order to solve the above problems, a multi-shell tank according to one aspect of the present disclosure,
an inner tank;
an outer tank surrounding the inner tank;
a cylindrical inner skirt extending vertically from the outer wall of the inner tank to the foundation;
A cylindrical outer skirt is arranged on the radially outer side of the inner skirt and extends in the vertical direction from the outer wall of the outer tank to the foundation.

Further, a ship according to one aspect of the present disclosure includes the multi-shell tank and a hull on which the multi-shell tank is mounted.

This disclosure provides a structure that can improve the strength of the tank's support structure in a multi-shell tank and in a ship equipped with the tank.

FIG. 1 is a vertical cross-sectional view of a multi-shell tank according to an embodiment of the present disclosure. FIG. 2 is a vertical sectional view showing installation example 1 of a multi-shell tank. FIG. 3 is a vertical sectional view showing installation example 2 of a multi-shell tank. FIG. 4 is a vertical sectional view showing installation example 3 of a multi-shell tank. FIG. 5 is a vertical sectional view showing installation example 4 of a multi-shell tank. FIG. 6 is a vertical sectional view showing installation example 5 of a multi-shell tank. FIG. 7 is a vertical cross-sectional view of a multi-shell tank illustrating a connection structure between an inner skirt, an outer tank, and an outer skirt of the multi-shell tank. FIG. 8 is an enlarged vertical cross-sectional view of a connecting portion between an inner skirt, an outer tank, and an outer skirt of a multi-shell tank showing Example 1 of the connecting shell. FIG. 9 is an enlarged vertical cross-sectional view of a connecting portion between an inner skirt, an outer tank, and an outer skirt of a multi-shell tank showing Example 2 of the connecting shell. FIG. 10 is an enlarged vertical cross-sectional view of the connection between the inner skirt, the outer tank, and the outer skirt of a multi-shell tank in which the connecting shell is provided with a heat insulating material. FIG. 11 is an enlarged vertical cross-sectional view of a connecting portion between an inner skirt, an outer tank, and an outer skirt of a multi-shell tank showing Example 3 of the connecting shell. FIG. 12 is an enlarged vertical cross-sectional view of a connecting portion between an inner skirt, an outer tank, and an outer skirt of a multi-shell tank showing Example 3 of the connecting shell. FIG. 13 is an enlarged vertical cross-sectional view of a connecting portion between an inner skirt, an outer tank, and an outer skirt of a multi-shell tank showing Example 4 of the connecting shell.

Next, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a multi-shell tank 1 according to an embodiment of the present disclosure. A multi-shell tank 1 shown in FIG. 1 is a low-temperature container that stores low-temperature liquefied gas such as liquefied hydrogen or liquefied natural gas. The multi-shell tank 1 is supported on a foundation 10 via an inner skirt 2 and an outer skirt 6. The foundation 10 may be, for example, the hull of a liquefied gas carrier or a concrete base installed on the ground.

The multi-shell tank 1 is a spherical tank. However, the multi-shell tank 1 is not limited to a spherical tank, and may also be a deformed spherical tank in the shape of an oblate ellipsoid, a stretch tank with hemispherical top and bottom and a cylindrical part in between, or a square tank in the shape of a rectangular parallelepiped. good. The multi-shell tank 1 includes an inner tank 3 containing liquefied gas and an outer tank 4 surrounding the inner tank 3. The inner tank 3 and the outer tank 4 are separated in the radial direction, and a heat insulating layer is provided between the inner tank and the outer tank 4. A heat insulating material may be filled between the inner and outer tanks, or a vacuum heat insulating layer may be provided between the inner and outer tanks. Note that the multi-shell tank 1 according to the present embodiment is a double-shell tank that includes an inner tank 3 and an outer tank 4, but the present disclosure can also be applied to a multi-shell tank 1 that includes three or more multiple tanks. .

The inner skirt 2 as a whole has a cylindrical shape extending in the vertical direction from the outer wall of the inner tank 3 to the foundation 10. The outer skirt 6 has a cylindrical shape extending vertically from the outer wall of the outer tank 4 to the foundation 10. The outer skirt 6 has a larger diameter than the inner skirt 2, and the inner skirt 2 is arranged inside the outer skirt 6. In other words, the inner skirt 2 and the outer skirt 6 constitute a support structure for the tank, which is made up of a double inner and outer cylindrical body.

In the multi-shell tank 1 illustrated in FIG. 1, the upper part of the inner skirt 2 is connected to the equator E of the inner tank 3 or its vicinity, and the upper part of the outer skirt 6 is connected to the equator E of the outer tank 4 or its vicinity. ing. The vertical dimensions (i.e., heights) of the inner skirt 2 and the outer skirt 6 are substantially the same. However, the connection position of the inner skirt 2 in the inner tank 3 and the connection position of the outer skirt 6 in the outer tank 4 are not limited to this example. The smaller the vertical dimensions of the inner skirt 2 and the outer skirt 6, the more advantageous from the viewpoint of cost and strength. On the other hand, when the contents of the inner tank 3 are at extremely low temperatures, it is desirable that the vertical dimension of the inner skirt 2 be larger in order to reduce the influence of cold heat on the outer tank 4 and the foundation 10. In this way, the connection position of the inner skirt 2 in the inner tank 3 and the connection position of the outer skirt 6 in the outer tank 4 are determined depending on the state of the foundation 10 on which the multi-shell tank 1 is installed and the contents stored in the inner skirt 2. is preferably selected. In the illustrated multi-shell tank 1, the equator E of the inner tank 3 and the equator E of the outer tank 4 are substantially at the same height, but the height positions of the equator E of the inner tank 3 and the outer tank 4 are May be different.

In the multi-shell tank 1 illustrated in FIG. 2, the inner skirt 2 is connected to the inner tank 3 below the equator E, and the outer skirt 6 is connected to the outer tank 4 at or near the equator E. The vertical dimension of the inner skirt 2 is smaller than the vertical dimension of the outer skirt 6.

In the multi-shell tank 1 illustrated in FIG. 3, the inner skirt 2 is connected to the equator E of the inner tank 3 or its vicinity, and the outer skirt 6 is connected to the outer tank 4 below the equator E. In this case, the vertical dimension of the inner skirt 2 is larger than the vertical dimension of the outer skirt 6. Furthermore, the inner skirt 2 of the multi-shell tank 1 illustrated in FIG. 2 and the outer skirt 6 of the multi-shell tank 1 illustrated in FIG. The outer skirt 6 may be connected to the lower part of the outer tank 4 than the equator E.

The multi-shell tank 1 illustrated in FIG. 4 is mounted on a ship 100. The ship 100 includes a hull 10A serving as a foundation 10 that supports the multi-shell tank 1. A hold 12 for accommodating a cargo tank is provided in the hull 10A, and a multi-shell tank 1 is supported on a deck 11 disposed within the hold 12. More specifically, the hull 10A has a deck 11 having a uniform height in a hold 12, and an inner skirt 2 and an outer skirt 6 are provided upright on the deck 11. The inner skirt 2 is connected to the equator E of the inner skirt 2, and the outer skirt 6 is connected to the equator E of the inner tank 3, and the vertical dimensions of the inner skirt 2 and the outer skirt 6 are substantially the same. be.

The multi-shell tank 1 illustrated in FIG. 5 is mounted on a ship 100. The ship 100 includes a hull 10A that supports the multi-shell tank 1. The hull 10A is provided with a hold 12 for accommodating a cargo tank, and the multi-shell tank 1 is supported on

decks

11a and 11b arranged within the hold 12. The

decks

11a and 11b have an outer deck 11a on which an outer skirt 6 is erected, and an inner deck 11b, which is disposed closer to the center of the hull 10A than the outer deck 11a and on which an inner skirt 2 is erected. The inner skirt 2 is connected to the equator E of the inner skirt 2, and the outer skirt 6 is connected to the equator E of the inner tank 3, and the height positions of the upper ends of the inner skirt 2 and the outer skirt 6 are substantially the same. It is. Since the height of the inner deck 11b is lower than that of the outer deck 11a, the height of the inner skirt 2 in the vertical direction is greater than the height of the outer skirt 6 in the vertical direction.

The multi-shell tank 1 illustrated in FIG. 6 is mounted on a ship 100. The ship 100 includes a hull 10A that supports the multi-shell tank 1. The hull 10A is provided with a hold 12 for accommodating a cargo tank, and the multi-shell tank 1 is supported on

decks

11a and 11b arranged within the hold 12. The

decks

11a and 11b have an outer deck 11a on which an outer skirt 6 is erected, and an inner deck 11b, which is disposed closer to the center of the hull 10A than the outer deck 11a and on which an inner skirt 2 is erected. The inner skirt 2 is connected to the equator E of the inner skirt 2, and the outer skirt 6 is connected to the equator E of the inner tank 3, and the height positions of the upper ends of the inner skirt 2 and the outer skirt 6 are substantially the same. It is. Since the inner deck 11b is higher than the outer deck 11a, the height of the inner skirt 2 in the vertical direction is smaller than the height of the outer skirt 6 in the vertical direction. In the multi-shell tank 1 illustrated in FIGS. 4 to 6, the inner skirt 2 is connected to the equator E of the inner tank 3, and the outer skirt 6 is connected to the equator E of the outer tank 4, but the inner skirt 2 is connected to the equator E of the outer tank 4. The joining position of the skirt 2 and the outer skirt 6 is not limited to the equator E, and may be joined to a location other than the equator E as illustrated in FIGS. 2 and 3. Moreover, although the multi-shell tanks 1 illustrated in FIGS. 4 to 6 are all arranged in the hold 12 of the ship 100, the multi-shell tanks 1 may be arranged in a place other than the hold 12 of the ship 100.

[Connection structure between inner skirt 2 and outer tank 4]
Here, it is a vertical sectional view of the multi-shell tank 1 illustrating the connection structure of the inner skirt 2, outer tank 4, and outer skirt 6. As shown in FIG. 7, the outer tank 4 includes an outer tank upper shell 41, an outer tank lower shell 42, and a connecting shell 5 disposed between the outer tank upper shell 41 and the outer tank lower shell 42. The connecting shell 5 is disposed between the inner skirt 2 and the outer skirt 6, and between the upper and lower

outer tank shells

41 and 42.

The outer tank 4 of the multi-shell tank 1 illustrated in FIG. 7 has a spherical shell shape as a whole. The upper part ( That is, the spherical cutout portion corresponds to the outer tank upper shell 41, the middle portion corresponds to the connecting shell 5, and the lower portion (ie, the spherical crown portion) corresponds to the outer tank lower shell 42. The vertical cross section of the connecting shell 5 is arcuate.

FIG. 8 is an enlarged vertical sectional view of the connection portion between the inner skirt 2, outer tank 4, and outer skirt 6 of the multi-shell tank 1. The outer tank upper shell 41 and the connecting shell 5 are connected via a ring member 44. That is, the outer tank upper shell 41 and the ring member 44 are joined, and the ring member 44 and the connecting shell 5 are joined. The outer skirt 6 is joined to the ring member 44. However, the outer tank upper shell 41 and the connecting shell 5 may be directly joined without using the ring member 44, and in this case, the outer skirt 6 is joined to the outer tank upper shell 41 or the connecting shell 5. good.

The connecting shell 5 and the outer tank lower shell 42 are connected via the ring member 22. That is, the connecting shell 5 and the ring member 22 are joined, and the ring member 22 and the outer tank lower shell 42 are joined. The connecting shell 5 and the outer tank lower shell 42 are arranged so as to be continuous with the inner skirt 2 in between, but even if the inner edge of the connecting shell 5 and the outer edge of the outer tank lower shell are at different height positions, good. Further, the connecting shell 5 is a partially spherical shell having the same diameter as the outer tank upper shell 41 and the outer tank lower shell 42, but they may not have the same diameter. In this case, the joining angle between the connecting shell 5 and the inner skirt 2 and the joining angle between the connecting shell 5 and the outer tank upper shell 41 can be arbitrarily set in consideration of field workability and the like.

The inner skirt 2 includes an inner skirt upper part 21 , an inner skirt lower part 23 , and a ring member 22 disposed between the inner skirt upper part 21 and the ring member 22 . In this way, the ring member 22 serves both as a component of the inner skirt 2 and as a component of the outer tank 4. The inner skirt upper part 21 is joined to a ring member 34 that is a component of the inner tank 3. However, the inner skirt upper part 21 may be joined to the outer wall of the inner tank 3.

In the multi-shell tank 1 having the above configuration, the inner tank 3 and the outer tank lower shell 42 are supported by the inner skirt 2, and the outer tank upper shell 41 is supported by the outer skirt 6. Therefore, the connection shell 5 is not required to have the strength to support the inner tank 3 and the outer tank 4 (however, if granular insulation material is loaded between the inner tank 3 and the outer tank upper shell 41, (requires strength to support the insulation material). In other words, it is sufficient that the connecting shell 5 can airtightly close the space between the inner skirt 2 and the outer skirt 6. Therefore, the connection shell 5 is not limited to a partial spherical shell, and the following embodiments may be adopted in consideration of the situation in which the multi-shell tank 1 is installed, the nature of the contents, improvement of workability, etc. .

The connecting shell 5 (5B) illustrated in FIG. 9 is a substantially horizontal annular flat plate. The outer edge 51 of the connecting shell 5B is sandwiched between the outer skirt 6 and the outer shell 41 from above and below, and is joined to both the outer skirt 6 and the outer shell 41. However, it is sufficient that the outer edge 51 of the connecting shell 5B is joined to at least one of the outer skirt 6 and the outer shell 41. The lower edge of the outer shell 41, the connecting shell 5, and the upper edge of the outer skirt 6 have substantially the same outer diameter. As a result, the outer shell 41, the connecting shell 5, and the outer skirt 6 are connected to form a smooth outer surface with few irregularities. Note that "substantially the same" includes not only the strictly same value, but also a range of slight differences such that the series of connections consisting of the outer shell 41, the connecting shell 5, and the outer skirt 6 form a smooth outer surface with few irregularities.

The inner edge 52 of the connecting shell 5 is joined to both the inner skirt upper part 21 and the ring member 22 in such a manner that it is sandwiched between the upper and lower parts of the inner skirt upper part 21 and the ring member 22. However, the inner edge 52 of the connecting shell 5B only needs to be joined to the upper and lower middle parts of the inner skirt 2. For example, the inner edge 52 of the connecting shell 5B is connected to the upper and lower parts of the inner skirt 2 and the lower part 23 of the inner skirt 2. The ring member 22 may be connected to the ring member 22 disposed at.

When the disc-shaped connecting shell 5B is employed in this way, since the connecting shell 5B is composed of a flat plate, it is easier to mold the connecting shell 5B itself compared to the case where it is a partially spherical shell. In addition, since the connecting portion between the connecting shell 5B and the inner skirt 2 and the connecting portion between the connecting shell 5B and the outer skirt 6 and/or the outer tank upper shell 41 do not become narrow, it is difficult to join the connecting shell 5B. Space can be secured.

As shown in FIG. 10, in a multi-shell tank 1 having a disc-shaped connecting shell 5B, a heat insulating material 7 may be provided to cover the outer surface of the connecting shell 5. This heat insulating material 7 is provided over the outer wall of the inner skirt 2, the lower surface of the connecting shell 5, and the inner wall of the outer skirt 6, and the heat insulating material 7 suppresses heat input between the tanks. However, the heat insulating material 7 may be provided over the outer wall of the inner skirt 2, the upper surface of the connecting shell 5, and the inner wall of the outer skirt 6. When the connection shell 5B is formed of a flat plate as illustrated in FIG. 10, it is easy to attach the heat insulating material 7 to the connection shell 5.

The connecting shell 5 (5C) shown in FIG. 11 has a first annular plate 55 and a second annular plate 54, which are two substantially horizontal annular flat plates, and the two

annular plates

54, 55 are connected by a cylinder 56 extending in the vertical direction. The cylinder 56 is sandwiched between the upper and lower

annular plates

54, 55, and the end face of the cylinder 56 is joined to the main surface of the

annular plates

54, 55. The first annular plate 55 has the outer edge 51 of the connecting shell 5, and the second annular plate 54 has the inner edge 52 of the connecting shell 5. The two-stage

annular plates

54, 55 of the connecting shell 5C may be the inner second annular plate 54 in the lower stage and the outer first annular plate 55 in the upper stage (see FIG. 11), or the inner second annular plate 54 in the upper stage and the outer first annular plate 55 in the lower stage (see FIG. 12). A heat insulating material 7 may be provided on the outer surface or inner surface of the connecting shell 5C.

The outer edge 51 of the connecting shell 5C is joined to both the outer skirt 6 and the outer tank upper shell 41 in such a manner that it is sandwiched between the upper and lower sides of the outer skirt 6 and the outer tank upper shell 41. However, the outer edge 51 of the connecting shell 5C may be joined to the outer skirt 6 or the outer tank upper shell 41. The inner edge 52 of the connecting shell 5C is joined to both the inner skirt upper part 21 and the ring member 22 in such a manner that it is sandwiched between the upper and lower parts of the inner skirt upper part 21 and the ring member 22. However, the inner edge 52 of the connecting shell 5C only needs to be joined to the upper and lower middle parts of the inner skirt 2. For example, the inner edge 52 of the connecting shell 5C is connected to the upper and lower parts of the inner skirt 2 and the lower part 23 of the inner skirt 2. The ring member 22 may be connected to the ring member 22 disposed at.

In such a connecting shell 5C, when stress that tends to cause a relative displacement between the outer edge 51 and the inner edge 52 of the connecting shell 5C due to thermal contraction or vibration of the multi-shell tank 1 acts on the connecting shell 5, By deforming the

annular plates

54, 55 and the cylindrical body 56, stress generated in the connection shell 5 and the joint portions of the inner skirt 2 and the outer skirt 6 with the connection shell 5 is suppressed. In this way, the

annular plates

54 and 55 and the cylindrical body 56 of the connection shell 5C function as a deformation allowing portion 58 that allows relative displacement between the outer edge 51 and the inner edge 52 of the connection shell 5.

The aspect of the deformation allowing portion 58 included in the connection shell 5C is not limited to the above. The connection shell 5 (5D) illustrated in FIG. 13 is a substantially horizontal annular flat plate, and is provided with a deformation allowing portion 57 that continues in the circumferential direction at a midway point in the radial direction. The deformation allowing portion 57 allows the connecting shell 5 to be deformed, particularly in the horizontal direction. The deformation allowing portion 57 of the connecting shell 5D may have a concave or convex ridge shape, or a corrugated shape. Alternatively, the deformation allowing portion 57 of the connecting shell 5D may be formed of a bellows. A heat insulating material 7 may be provided on the outer surface or inner surface of the connection shell 5D. In such a connecting shell 5D, when a stress that causes a relative displacement between the outer edge 51 and the inner edge 52 of the connecting shell 5D acts on the connecting shell 5 due to thermal contraction or vibration of the multi-shell tank 1, By actively deforming the deformation allowing portion 57, stress generated in the connection shell 5 and the joint portions of the inner skirt 2 and the outer skirt 6 with the connection shell 5 is suppressed.

[Summary]
The multi-shell tank 1 according to the first aspect of the present disclosure comprises:
An inner tank 3;
An outer tank 4 surrounding the inner tank 3;
A cylindrical inner skirt 2 extending vertically from the outer wall of the inner tank 3 to the foundation 10;
It is characterized by having a cylindrical outer skirt 6 that is arranged radially outside the inner skirt 2 and extends vertically from the outer wall of the outer tank 4 to the foundation 10.

In the multi-shell tank 1 having the above configuration, the inner skirt 2 that supports the inner tank 3 and the outer skirt 6 that supports the outer tank 4 are provided independently. As a result, compared to the case where the inner tank 3 and the outer tank 4 are supported by a single skirt, the load to be supported is distributed, the stress acting on the

skirts

2 and 6 is reduced, and the multi-shell tank 1 and its housing are It becomes easy to provide the

skirts

2 and 6 with strength capable of withstanding the swinging of objects. That is, it is possible to provide a structure in which the strength of the tank support structure can be improved in the multi-shell tank 1.

A multi-shell tank 1 according to a second item of the present disclosure is the multi-shell tank 1 according to the first item, in which an outer tank 4 is connected to an outer tank upper shell 41 supported by an outer skirt 6 and an inner skirt 2. It includes a supported outer tank lower shell 42 and a connecting shell 5 disposed between an outer tank upper shell 41 and an outer tank lower shell 42.

According to the multi-shell tank 1 having the above configuration, the outer tank lower shell 42 is supported by the inner skirt 2, and the outer tank upper shell 41 is supported by the outer skirt 6, so that the loads of the inner tank 3 and outer tank 4 are reduced. The unsupported connection shell 5 allows a relatively high degree of freedom in design.

The multi-shell tank 1 according to the third item of the present disclosure is the multi-shell tank 1 according to the second item, which has a lower edge of the outer tank upper shell 41 and an outer tank connected to the lower edge of the outer tank upper shell 41. The upper edge of the skirt 6 has substantially the same outer diameter. Note that the outer tank upper shell 41 and the outer skirt 6 do not need to be directly joined.

According to the multi-shell tank 1 having the above configuration, the outer tank upper shell 41 and the outer skirt 6 constitute one continuous shell, and the outer tank upper shell 41 is stably supported by the outer skirt 6.

The multi-shell tank 1 according to the fourth item of the present disclosure is the multi-shell tank 1 according to the second or third item, in which a heat insulating material 7 is provided on the outer surface or inner surface of the connecting shell 5 and extends to the inner skirt 2 and the outer skirt 6. are arranged.

According to the multi-shell tank 1 having the above configuration, heat input from the outside through the connecting shell 5, inner skirt 2, and outer skirt 6 can be suppressed.

The multi-shell tank 1 according to the fifth item of the present disclosure is the multi-shell tank 1 according to any one of the second to fourth items, in which the connecting shell 5 has a relative relationship between the outer edge 51 and the inner edge 52 of the connecting shell 5. It has

deformation allowing portions

57 and 58 that allow a certain amount of displacement.

According to the multi-shell tank 1 having the above configuration, if there is a difference in thermal contraction between the inner tank 3 and the outer tank 4, or if vibration causes a relative displacement between the outer edge 51 and the inner edge 52 of the connecting shell 5, When such stress is generated, the

deformation allowing portions

57 and 58 actively deform to allow displacement of the outer edge 51 and inner edge 52 of the connection shell 5, and as a result, the generated stress can be reduced.

The multi-shell tank 1 according to the sixth item of the present disclosure is the multi-shell tank 1 according to any one of the second to fourth items, in which the connecting shell 5 is connected to the first annular plate 55 and the first annular plate 55. It has a second annular plate 54 arranged apart from each other in the vertical direction, and a cylindrical body 56 that connects the first annular plate 55 and the second annular plate 54 in the vertical direction.

According to the multi-shell tank 1 having the above configuration, when a stress that tends to cause a relative displacement between the outer edge 51 and the inner edge 52 of the connecting shell 5 occurs, the first annular plate 55 and the second annular plate As a result of the deformation of 54, the outer edge 51 and inner edge 52 of the connection shell 5 are allowed to be displaced, thereby reducing the stress generated.

In the multi-shell tank 1 according to the seventh item of the present disclosure, in the multi-shell tank 1 according to any one of the first to sixth items, the vertical dimension of the outer skirt 6 is larger than the vertical dimension of the inner skirt 2. is small.

In the multi-shell tank 1 having the above configuration, when the inner tank 3 contains low-temperature contents, the inner tank 3 is lower in temperature than the outer tank 4. Since the inner skirt 2 supporting the inner tank 3 is longer than the outer skirt 6 supporting the outer tank 4, the influence of cold heat on the foundation 10 can be suppressed.

The ship 100 according to the eighth item of the present disclosure comprises a multi-hull tank 1 according to any one of the first to sixth items, and a hull 10A on which the multi-hull tank 1 is mounted. Note that the ship 100 is not limited to one equipped with a propulsion system, and may broadly include a floating structure.

The multi-shell tank 1 having the above configuration has the strength to withstand shaking, so it is suitable as a container to be mounted on a transportation means such as the ship 100.

A ship 100 according to a ninth item of the present disclosure is the ship 100 according to the eighth item, in which the hull 10A has an inner deck 11b that supports the inner skirt 2, and an outer deck that is arranged at a higher position than the inner deck 11b. It has an outer deck 11a that supports the skirt 6.

According to the above configuration, it is possible to realize a ship 100 including a multi-shell tank 1 in which the inner skirt 2 that supports the inner tank 3 is longer than the outer skirt 6 that supports the outer tank 4.

A ship 100 according to a tenth item of the present disclosure is the ship 100 according to the eighth item, in which the hull 10A has a deck 11 that supports the inner skirt 2 and the outer skirt 6 on substantially the same plane. be.

According to the above configuration, since the inner skirt 2 and the outer skirt 6 are supported on substantially the same plane, the worker works on the same floor of the deck 11 when constructing or maintaining the inner skirt 2 and the outer skirt 6. This improves work efficiency.

The above discussion of the disclosure has been presented for purposes of illustration and description, and is not intended to limit the disclosure to the form disclosed herein. For example, although in the foregoing detailed description various features of the disclosure are grouped together in a single embodiment for the purpose of streamlining the disclosure, some of the features may also be combined. Additionally, features included in this disclosure may be combined in alternative embodiments, configurations, or aspects other than those discussed above.

Claims

an inner tank;
an outer tank surrounding the inner tank;
a cylindrical inner skirt extending vertically from the outer wall of the inner tank to the foundation;
a cylindrical outer skirt disposed radially outside the inner skirt and extending in the vertical direction from the outer wall of the outer tank to the foundation;
Multi-shell tank.
A connection in which the outer tank is arranged between an outer tank upper shell supported by the outer skirt, an outer tank lower shell supported by the inner skirt, and the outer tank upper shell and the outer tank lower shell. including the shell;
A multi-shell tank according to claim 1.
The lower edge of the outer tank upper shell and the upper edge of the outer skirt connected to the lower edge of the outer tank upper shell have substantially the same outer diameter.
A multi-shell tank according to claim 2.
A heat insulating material extending to the inner skirt and the outer skirt is disposed on the outer surface or inner surface of the connecting shell,
The multi-shell tank according to claim 2 or 3.
The connection shell has a deformation allowing portion that allows relative displacement between the outer edge and the inner edge of the connection shell.
A multi-shell tank according to any one of claims 2 to 4.
The connection shell connects a first annular plate, a second annular plate disposed apart from the first annular plate in the vertical direction, and the first annular plate and the second annular plate in the vertical direction. having a cylindrical body,
A multi-shell tank according to any one of claims 2 to 4.
The vertical dimension of the outer skirt is smaller than the vertical dimension of the inner skirt.
A multi-shell tank according to any one of claims 1 to 6.
The multi-shell tank according to any one of claims 1 to 7,
and a hull on which the multi-shell tank is mounted,
ship.
The hull has an inner deck that supports the inner skirt, and an outer deck that is located at a higher position than the inner deck and supports the outer skirt.
A ship according to claim 8.
the hull has a deck that supports the inner skirt and the outer skirt in substantially the same plane;
A ship according to claim 8.