KR20220139786A - Liquefied gas storage tank and vessel comprising the same - Google Patents

Abstract

The present invention relates to a liquefied gas storage tank and a vessel including the same. The liquefied gas storage tank of the present invention consists of a first barrier, a first insulation wall, a second barrier, and a second insulation wall and stores extremely low-temperature materials. The first insulation wall may include a connection insulation wall provided in the space between neighboring fixed insulation walls in a state that unit elements formed by stacking the second insulation wall, the secondary barrier, and a fixed insulation wall, a part of the first insulation wall, are neighbored and so disposed. The liquefied gas storage tank may include: a first stepped part which is formed on side surfaces forward and backward and left and right of the connection insulation wall; a second stepped part which is formed on side surfaces forward and backward and left and right of the fixed insulation wall; a first slit which is formed between the connection insulation wall and the fixed insulation wall by the first stepped part and the second stepped part when inserting and installing the connection insulation wall between neighboring fixed insulation walls; and a first charging insulator which charges the first slit.

Description

Liquefied gas storage tank and vessel comprising the same

The present invention relates to a liquefied gas storage tank and a ship including the same.

According to recent technology development, liquefied gas such as liquefied natural gas (LNG) and liquefied petroleum gas (LPG) is widely used to replace gasoline or diesel.

In addition, in ships that transport or store liquefied gas such as LNG at sea, LNG RV (Regasification Vessel), LNG FPSO (Floating, Production, Storage and Offloading), LNG FSRU (Floating Storage and Regasification Unit), etc. Storage tanks (so-called "cargo holds") are installed for storing LNG in a cryogenic liquid state.

In addition, the liquefied gas storage tank may generate boil-off gas (BOG) due to intrusion of heat from the outside, and the natural vaporization rate (BOR), which is the vaporization rate of the boil-off gas through a thermal insulation design. It is a key technology in the design of the liquefied gas storage tank. In addition, since the liquefied gas storage tank is exposed to various loads such as sloshing, it may be essential to secure the mechanical strength of the insulation panel.

Considering this point, the thickness range of the primary insulating wall and the secondary insulating wall may be related to the mechanical strength of the liquefied gas storage tank. Accordingly, studies are being actively conducted to remove the low-temperature burden of the secondary barrier while maintaining the mechanical strength of the secondary barrier.

The present invention was created to solve the problems of the prior art as described above, and an object of the present invention is to make the thickness of the first insulating wall the same as or similar to that of the second insulating wall in the total thickness of the insulating wall, so that the mechanical It is to provide a liquefied gas storage tank capable of reducing the low temperature burden and the sloshing burden of the secondary barrier while maintaining the strength at a certain level, and a ship including the same.

In addition, an object of the present invention is to make the thickness of the primary insulating wall the same as or similar to the secondary insulating wall in the total thickness of the insulating wall, so that the low temperature burden and sloshing burden of the secondary barrier in the range where brittle fracture of the hull does not occur To provide a liquefied gas storage tank and a ship including the same to reduce

In addition, it is an object of the present invention to provide a liquefied gas storage tank and a ship including the same to improve the configuration of the secondary barrier to increase the thermal insulation performance.

In addition, it is an object of the present invention to provide a liquefied gas storage tank and a ship including the same, which improve the configuration of the fixing member for fixing the secondary insulating wall to the hull, thereby increasing the thermal insulation performance as well as reducing the man-hours.

In addition, an object of the present invention is to optimize the slit provided to prepare for the contraction and expansion of the primary insulating wall formed on the secondary barrier, and to minimize the convection phenomenon and heat penetration into the secondary barrier generated through the slit. It is to provide a liquefied gas storage tank and a ship including the same, which can improve the stability of the primary insulating wall and reduce the low temperature burden on the secondary barrier.

A liquefied gas storage tank according to an aspect of the present invention is a liquefied gas storage tank for storing cryogenic materials consisting of a primary barrier, a primary insulating wall, a secondary barrier, and a secondary insulating wall, wherein the primary insulating wall is In a state in which unit elements formed by laminating a thermal wall, the secondary barrier, and a fixed thermal insulating wall that are part of the primary insulating wall are arranged adjacently, a connection insulating wall provided in a space between the adjacent fixed insulating walls; a first step portion formed on front, rear, left, and right sides of the connection insulating wall; a second step portion formed on front, rear, left, and right sides of the fixed insulating wall; a first slit formed by the first step portion and the second step portion between the connection insulation wall and the fixed insulation wall when the connection insulation wall is inserted between the adjacent fixed insulation walls; and a first filling insulating material filling the first slit.

Specifically, the first step portion is formed by forming the front, rear, left and right widths of the upper portion of the connection insulating wall to be narrower than the front, rear, left and right widths of the lower portion of the connection insulation wall, and the second step portion is, is formed to be narrower than the front, rear, left and right widths of the lower part of the fixed insulating wall, and the first charging insulating material is installed so that the lower part of the connecting insulating wall and the lower part of the fixed insulating wall are adjacent to each other, so that the upper part of the connecting insulating wall and the upper part of the connecting insulating wall The space provided between the upper portions of the fixed insulating wall may be filled in the first slit.

Specifically, a plurality of second slits are formed in the longitudinal direction and the width direction of the fixed insulating wall; and at least one third slit formed in the longitudinal direction of the connecting insulating wall and positioned on the same line as the second slit formed in the longitudinal direction when the connecting insulating wall is inserted between the fixed insulating walls. The second slit and the third slit are formed to have a depth corresponding to a thickness of about half of the thickness of the fixed insulating wall and the connection insulating wall, the filling insulating material is not filled therein, and the first The first slit filled with the insulating material is formed to be at least longer than the depth of each of the second slit and the third slit, and the thermal convection path through the first slit, the second slit and the third slit is It can be done discontinuously.

Specifically, the first insulating wall and the second insulating wall may have the same or similar thickness.

A liquefied gas storage tank according to the present invention and a ship having the same, by configuring the thickness of the first insulation wall to be the same as or similar to that of the second insulation wall in the total thickness of the first insulation wall and the second insulation wall covering the connection insulation wall, 2 It is possible to maintain the mechanical strength of the barrier thermal barrier at a certain level, as well as reduce the low-temperature burden and sloshing burden of the secondary barrier, thereby preventing damage to the secondary barrier.

In addition, the liquefied gas storage tank according to the present invention and a ship having the same, by configuring the thickness of the first insulation wall to be the same as or similar to the second insulation wall in the total thickness of the first insulation wall and the second insulation wall covering the connection insulation wall , It is possible to prevent brittle fracture of the hull and reduce the low-temperature burden and sloshing burden of the secondary barrier.

In addition, the liquefied gas storage tank according to the present invention and a ship having the same, by providing an auxiliary heat insulating plate on the lower surface of the connection insulating wall provided in the space between the neighboring primary insulating walls constituting the unit element, the unit element It is possible to further increase the thermal insulation performance at the connection part of the secondary insulating wall.

In addition, the liquefied gas storage tank and the ship having the same according to the present invention can improve the configuration of the secondary barrier to increase the thermal insulation performance.

In addition, the liquefied gas storage tank according to the present invention and a ship having the same, by applying a non-adhesive elastic insulating material as a leveling member of the secondary insulating wall between the secondary insulating wall and the hull, even without using the existing mastic and leveling wedge hull It is possible to level the deformation part of the tank and increase the thermal insulation performance of the tank.

In addition, the liquefied gas storage tank according to the present invention and a ship having the same, a cleat structure by a protrusion provided to protrude to the outside at the lower side of the unit panel of the secondary insulating wall, and a stud bolt fixed to the hull. By fixing the unit panel of the adjacent secondary insulating wall, it is possible to reduce the man-hour compared to the method of fixing the unit panel with stud bolts by drilling a hole in the secondary insulating wall.

In addition, the liquefied gas storage tank and the ship having the same according to the present invention optimize the slit provided to prepare for the contraction and expansion of the primary insulating wall formed on the secondary barrier, and the convection phenomenon generated through the slit and By improving the slit structure and composing various filling insulation materials to fill the slit to minimize heat penetration into the secondary barrier, the stability of the primary insulating wall according to the slit formation can be improved, and at the same time, the It is possible to reduce the burden of low temperature, and it is possible to prevent damage to the primary insulating wall and the secondary barrier.

1 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a first embodiment of the present invention.
Figure 2 is a partial perspective view for explaining the liquefied gas storage tank according to the first embodiment of the present invention.
3 is a view for explaining the primary barrier of the liquefied gas storage tank according to the first embodiment of the present invention.
4 (a) and (b) are views showing the tensile force of the secondary barrier according to the change in the thickness of the primary insulating wall and the secondary insulating wall.
5 to 8 are structures while varying the thickness of the first and second insulating walls of the first case in order to derive the thickness of the first and second insulating walls of the liquefied gas storage tank according to the first embodiment of the present invention; Figures showing the results of analysis.
9 to 12 show the thickness of the first and second insulation walls of the second case performed to derive the thicknesses of the first and second insulation walls of the liquefied gas storage tank according to the first embodiment of the present invention while varying the thicknesses of the first and second insulation walls; Figures showing the results of structural analysis.
13 to 16 show the thickness of the first and second insulation walls of the third case performed to derive the thicknesses of the first and second insulation walls of the liquefied gas storage tank according to the first embodiment of the present invention while varying the thicknesses of the first and second insulation walls; Figures showing the results of structural analysis.
17 to 20 show the thickness of the first and second insulation walls of the fourth case performed to derive the thicknesses of the first and second insulation walls of the liquefied gas storage tank according to the first embodiment of the present invention while varying the thicknesses of the first and second insulation walls; Figures showing the results of structural analysis.
21 is a graph showing the low-temperature stress of the secondary barrier and the probability of brittle fracture of the hull according to the thickness change of the primary and secondary thermal insulation walls.
22, 23 and 24 are views for explaining various configurations of the secondary barrier of the liquefied gas storage tank according to the first embodiment of the present invention.
25 is a partial cross-sectional view for explaining the right-angled corner structure of the liquefied gas storage tank according to the first embodiment of the present invention.
26 is a partial cross-sectional view for explaining the obtuse corner structure of the liquefied gas storage tank according to the first embodiment of the present invention.
27 is a graph showing the thermal conductivity according to the material used for the primary insulating material and the secondary insulating material of the liquefied gas storage tank of the present invention.
28 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a second embodiment of the present invention.
29 is a partial perspective view for explaining a liquefied gas storage tank according to a second embodiment of the present invention.
30 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a third embodiment of the present invention.
31 is an enlarged view of a main part of a liquefied gas storage tank according to a third embodiment of the present invention.
32 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a fourth embodiment of the present invention.
33 is a view for explaining a filling insulating material filling a plurality of second slits provided in the first slit forming a gap between the connection insulating wall and the fixed insulating wall constituting the primary insulating wall;
34 is a view for explaining a filling insulating material according to another embodiment of filling a first slit forming a gap between a connection insulating wall and a fixed insulating wall constituting the primary insulating wall and a plurality of second slits provided in the fixed insulating wall to be.
35 is a first slit forming a gap between the connection insulating wall and the fixed insulating wall constituting the primary insulating wall, and a plurality of second slits provided in the fixed insulating wall. It is a drawing.
36 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a fifth embodiment of the present invention.
37 is a cross-sectional view of the connection insulating wall taken along line AA' of FIG. 36;
FIG. 38 is a cross-sectional view of a unit element formed by stacking the secondary insulating wall, the secondary barrier, and the fixed insulating wall forming the primary insulating wall cut along the line BB′ of FIG. 36 .
39 and 40 are views for explaining a filling insulating material filling the first slit forming a gap between the connection insulating wall and the fixed insulating wall forming the primary insulating wall.
41 and 42 are views showing the structural analysis results of the liquefied gas storage tank according to the fifth embodiment of the present invention.
43 to 46 show the convection path and secondary depending on the structure of the slit in the liquefied gas storage tank according to the fifth embodiment and the liquefied gas storage tank according to the comparative example and the presence or absence of application of a filling insulation filling the slit. It is a diagram for explaining and comparing the temperature of the barrier.
47 is a graph comparing the temperature of the secondary barrier under the slit according to the presence or absence of a filling insulating material for filling the slit in the liquefied gas storage tank according to the fifth embodiment of the present invention and the liquefied gas storage tank according to the comparative example.
48 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a sixth embodiment of the present invention.
49 is a cross-sectional view of the connection insulating wall taken along line AA′ of FIG. 48 .
FIG. 50 is a cross-sectional view of a unit element formed by stacking a secondary insulating wall, a secondary barrier, and a fixed insulating wall constituting the primary insulating wall cut along the line BB′ of FIG. 48 .
51 is an enlarged view illustrating a state in which a filling insulating material is filled in the first slit forming a gap between the connection insulating wall and the fixed insulating wall constituting the primary insulating wall.
52 is a perspective view for explaining a liquefied gas storage tank according to a seventh embodiment of the present invention.
53 (a) to (c) are views showing the plane, side, and cross-section of the unit element in which the fixed heat insulating walls constituting the secondary insulating wall, the secondary barrier, and the primary insulating wall of FIG. 52 are stacked.
54 (a) to (c) are views showing the plane, side, and cross-section of the connection insulating wall constituting the primary insulating wall of FIG. 52 .
55 (a) to (c) are views showing the plane, side, and cross-section of the connection insulating wall according to another embodiment constituting the primary insulating wall of FIG. 52 .
56 is a rear perspective view of a connection insulating wall according to another embodiment constituting the primary insulating wall of FIG. 52 .
57 is a view showing a cross-section of a portion in which the fixed insulating wall and the connecting insulating wall constituting the primary insulating wall are alternately connected.
58 is a view showing a cross-section of a portion in which a plurality of connection insulating walls constituting the primary insulating wall are continuously connected.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In the present specification, in adding reference numbers to the components of each drawing, it should be noted that only the same components are given the same number as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed herein is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present invention , should be understood to include equivalents or substitutes.

Also, terms including an ordinal number such as 1st, 2nd, etc. may be used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

Hereinafter, in this specification, liquefied gas may be used to encompass all gas fuels that are generally stored in a liquid state, such as LNG or LPG, ethylene, ammonia, etc. can be expressed as This can be applied to boil-off gas as well. In addition, for convenience, LNG may be used to encompass both NG (Natural Gas) in a liquid state as well as LNG in a supercritical state, etc. can

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a first embodiment of the present invention, Figure 2 is a partial perspective view for explaining a liquefied gas storage tank according to a first embodiment of the present invention. 3 is a view for explaining the primary barrier of the liquefied gas storage tank according to the first embodiment of the present invention.

1 to 2, the liquefied gas storage tank 1 according to the first embodiment of the present invention is provided on a ship and liquefied such as LNG, which is a cryogenic (about -160°C to -170°C) material. gas can be stored.

Although not shown, the ship provided with the liquefied gas storage tank (1) described below is a concept that encompasses offshore structures that float at a certain point on the sea and perform specific tasks in addition to merchant ships that transport cargo from the origin to the destination. let me know In addition, in the present invention, the liquefied gas storage tank (1) puts out that any type of tank for storing liquefied gas is included.

The liquefied gas storage tank (1) is a primary barrier (2) in contact with liquefied gas, a primary insulating wall (3) installed on the outside of the primary barrier (2), and a primary insulating wall (3) installed on the outside The secondary barrier (4) may be configured to include a secondary heat insulating wall (5) disposed on the outside of the secondary barrier (4). The liquefied gas storage tank (1) may be supported on the hull (7) by the mastic (6) installed between the secondary insulating wall (5) and the hull (7).

The liquefied gas storage tank 1 may need to optimize the thickness of the primary insulating wall 3 and the secondary insulating wall 5 in order to optimize the thermal insulation performance and storage capacity. For example, when polyurethane foam is used as the main material of the primary insulating wall (3) and the secondary insulating wall (5), the total thickness of the first insulating wall (3) and the thickness of the secondary insulating wall (5) is 250mm to 500 mm. In this regard, it will be described with reference to FIGS. 4 to 20 .

In the above, the liquefied gas storage tank 1 may include a flat surface and a corner structure. For example, the transverse wall in the front-rear direction of the liquefied gas storage tank 1, the floor between the transverse walls, the vertical wall, and the ceiling may correspond to a planar structure. In addition, for example, a structure in which the lateral wall, the floor, the vertical wall, and the ceiling of the liquefied gas storage tank 1 meet may correspond to a corner structure. Here, the corner structure may include an obtuse corner structure or a right angle corner structure. When the thickness of the primary insulating wall 3 or the secondary insulating wall 5 is changed, the change in the obtuse-angled corner structure or the right-angled corner structure may be accompanied. It will be described with reference to FIGS. 25 to 26 .

1 and 2 , the primary barrier 2 forms an accommodating space for accommodating liquefied gas, which is a cryogenic material, and may be made of a metal material. For example, the metal material may be a stainless steel material, but is not limited thereto. The primary barrier (2) can prevent leakage of liquefied gas to the outside together with the secondary barrier (4).

The primary barrier 2 is fixedly coupled to the upper portion of the primary insulating wall 3 by an anchor strip (not shown), and is installed so as to be in direct contact with liquefied gas, which is a cryogenic material stored in the liquefied gas storage tank 1 . can be

Referring to Figure 3, the primary barrier (2), a flat portion (21) in contact with the upper surface of the primary thermal insulation wall (3), a curved portion (22) for relieving contraction or expansion stress due to temperature (stress), It may be divided into a boundary portion 23 between the flat portion 21 and the curved portion 22 . For example, it may be formed of a corrugation membrane sheet made of a stainless steel material having a thickness of 1.0 to 1.5 mm, preferably a stainless steel material having a thickness of 1.0 to 1.2 mm. That is, the primary barrier may be formed in a wrinkle shape.

The primary barrier 2 may be formed to have a wrinkle shape having a first radius of curvature R1 and a second radius of curvature R2. That is, the primary barrier 2 of this embodiment forms a first radius of curvature R1 at the boundary 23 between the flat portion 21 and the curved portion 22, and the curved portion 22 has a second radius of curvature. It may be formed to have two types of radii of curvature R1 and R2 constituting (R2). For example, the first radius of curvature R1 may be smaller than the second radius of curvature R2 . The primary barrier 2 having a radius of curvature (R1, R2) is easy to inspect for welding because the upper part forms a gentle curve, and also flexibly responds to sloshing because the fluid hitting from the side flows directly. .

In addition, the primary barrier (2) of this embodiment, large corrugation (Large corrugation) and small corrugation (Small corrugation) can be formed to have the same horizontal and vertical wrinkle sizes in the entire area without distinction. That is, since the horizontal and vertical wrinkle sizes are the same in the entire primary barrier 2, the primary barrier can be easily manufactured.

Referring to Figure 1, the primary heat insulating wall (3) is designed to withstand the impact from the outside or liquefied gas sloshing from the inside while blocking heat intrusion from the outside, the primary barrier (2) And it can be installed between the secondary barrier (4).

The first thermal insulation wall 3 may have a structure in which the primary plywood 31 and the primary thermal insulation material 32 are sequentially stacked to the outside of the primary barrier 2, the primary plywood 31 It may correspond to the sum of the thickness and the thickness of the primary insulating material 32 . The first insulating wall 3 may be formed to a thickness of 160 mm to 250 mm.

The primary plywood 31 may be installed between the primary barrier 2 and the primary insulating material 32 .

The primary plywood 31 may be formed to a thickness of 6.5mm to 15mm.

The primary insulating material 32 may be formed of a material having excellent thermal insulation performance and excellent mechanical strength so as to withstand an impact from the outside or an impact caused by liquefied gas sloshing from the inside while blocking heat intrusion from the outside. have.

The primary insulating material 32 may be formed of polyurethane foam between the primary plywood 31 and the secondary barrier 4, and may correspond to a thickness range of 150 mm to 240 mm.

Referring to FIG. 1 , a part of the primary thermal insulation wall 3 , the secondary barrier 4 and the secondary thermal insulation wall 5 may be laminated to form a unit element. Here, a part of the primary insulating wall 3 constituting the unit element may be defined as the fixed insulating wall 3b, and the width of the fixed insulating wall 3b is the width of the secondary insulating wall 5 included in the unit element. It may have a smaller width. In addition, the fixed insulating wall (3b), the secondary barrier (4) and the secondary insulating wall (5) may be arranged in a pre-fixed state, but is not limited thereto, and each is separated in the liquefied gas storage tank (1). may be placed. Due to this, a portion of the secondary barrier 4 may be exposed on both sides of the primary insulating wall 3 . The unit elements may be disposed adjacent to each other, and in this case, the connecting insulation wall 3a may be installed in a space portion between the adjacent primary insulation walls 3 , that is, in a space portion where the secondary barrier 4 is exposed.

The secondary barrier 4 can be divided into a main barrier 41 and an auxiliary barrier 42, and the main barrier 41 is installed on the upper part of the secondary heat insulating wall 5 in a unit element, and the auxiliary barrier 42 is installed between the exposed main barrier 41 and the connection insulating wall 3a. At this time, the auxiliary barriers 42 are provided to interconnect the main barriers 41 provided in the unit elements adjacent to each other. That is, adjacent unit elements may be closed by the auxiliary barrier 42 and the connection insulating wall 3a stacked on the main barrier 41 .

The laminated structure of the portion where the connection insulating wall 3a is provided is described with reference to FIG. 2 . Connection insulation wall (3a) may be provided in a form in which the same or similar connection plywood (31a) and connection insulation material (32a) as described in the first insulation wall (3) constituting the unit element are stacked, in this specification, the first insulation Note that the thermal wall 3 may encompass the connecting insulating wall 3a and the fixed insulating wall 3b.

FIG. 2 shows the cross-sectional structure of the plane A-A' of FIG. 1 , and the connection insulation wall 3a may have a structure in which a connection plywood 31a and a connection insulation material 32a are stacked. The thickness of the connection insulating wall 3a may correspond to the sum of the thickness of the connection plywood 31a and the thickness of the connection insulating material 32a.

The connecting plywood (31a) may be formed to a thickness of 6.5mm to 15mm.

The connection insulating material 32a may be formed of polyurethane foam between the connection plywood 31a and the auxiliary barrier 42 of the secondary barrier 4, and may correspond to a thickness range of 150mm to 240mm.

As described above, the first insulating material 32 of the primary insulating wall 3 and the connecting insulating material 32a of the connecting insulating wall 3a may have the same thickness. However, in the case of the connection insulation material 32a of the connection insulation wall 3a, since the auxiliary barrier 42 is further laminated in addition to the main barrier 41 of the secondary barrier 4 at the bottom, the connection of the connection insulation wall 3a The insulating material 32a may have a thickness smaller than the thickness of the primary insulating material 32 of the primary insulating wall 3 by the thickness of the auxiliary barrier 42 .

The above-described connection insulating wall (3a), when the unit elements are arranged adjacent to each other, sealing the space portion generated between the adjacent secondary insulating walls (5) together with the auxiliary barrier (42) to block heat intrusion from the outside installed to perform its role.

However, since the connection insulation wall 3a is a structure inserted between the adjacent fixed insulation walls 3b constituting the unit element, it is weak in protecting the secondary barrier 4 under the connection insulation wall 3a from cryogenic temperatures. Have no choice but to. Accordingly, there is a high possibility that a problem occurs in the secondary barrier 4 under the connection insulating wall 3a where the main barrier 41 and the auxiliary barrier 42 overlap. Hereinafter, the connection insulation wall 3a will be mainly described.

The secondary barrier (4) may be installed between the primary insulating wall (3) and the secondary insulating wall (5) covering the insulating wall (3a), and liquefied gas leaks to the outside together with the primary barrier (2) can be prevented from becoming

The secondary barrier 4 at the lower end of the fixed insulating wall 3b includes the main barrier 41 as a single barrier, and the secondary barrier 4 at the lower end of the connecting insulating wall 3a is a main connecting unit element to each other. It may include a barrier 41 and an auxiliary barrier 42 provided on the secondary heat insulating wall 5 constituting the unit element.

The main barrier 41 is provided on the secondary heat insulating wall 5 constituting the unit element and may be formed to a thickness of 0.6 mm to 1.0 mm, and the main barrier 41 adjacent to each other is formed by stacking the auxiliary barriers 42 confidentiality can be achieved.

The auxiliary barrier 42 may be formed to a thickness of 0.6 mm to 1.0 mm as a configuration for connecting unit elements to each other and may be laminated on the main barrier 41 .

On the other hand, referring to FIGS. 1 and 2 , the secondary heat insulating wall 5, together with the fixed heat insulating wall 3b and the connecting heat insulating wall 3a, blocks heat intrusion from the outside while blocking an impact from the outside or from the inside. It can be designed to withstand the impact caused by liquefied gas sloshing. In addition, the secondary thermal insulation wall 5 may be installed between the secondary barrier 4 and the hull 7 , and may include a secondary thermal insulation material 51 and a secondary plywood 52 .

The secondary insulating wall 5 may have a structure in which a secondary insulating material 51 and a secondary plywood 52 are sequentially stacked to the outside of the secondary barrier 4, the thickness of the secondary insulating material 51 And the total thickness of the sum of the thickness of the secondary plywood 52 may be formed to 150mm to 240mm.

The second insulating material 51 may be formed of a material having excellent thermal insulation performance and excellent mechanical strength so as to withstand an impact from the outside or an impact caused by liquefied gas sloshing from the inside while blocking heat intrusion from the outside. have.

The secondary insulating material 51 may be formed of polyurethane foam between the secondary barrier 4 and the secondary plywood 52, and may be formed to a thickness of 140mm to 230mm.

The secondary plywood 52 may be installed between the secondary insulating material 51 and the hull 7 . For example, in addition, the secondary insulating material 51 may be installed in contact with the secondary plywood (52). The secondary plywood 52 may be formed to a thickness of 6.5 mm to 25 mm.

As described above, in the liquefied gas storage tank 1 according to this embodiment, the first insulating wall 3 has a thickness of 66% to 166% of the second insulating wall 5, and The connected insulating wall 3a covered has a thickness of 67% to 167% of the secondary insulating wall 5, so that the connecting insulating wall 3a has the same or similar thickness as the secondary insulating wall 5. can To be associated with this configuration, the connecting insulating material 32a of the connecting insulating wall 3a has a thickness of 90% to 110% of the secondary insulating material 51, so that the connecting insulating material 32a of the connecting insulating wall 3a is It may be configured to have the same or similar thickness as the secondary insulating material 51 . In this embodiment, although the portion of the fixed heat insulating wall 3b constituting the unit element is not mentioned in detail when the connecting heat insulating wall 3a is covered, the fixed heat insulating wall 3b is also connected and insulating in relation to the secondary heat insulating wall 5 Note that it is the same as or similar to the wall 3a.

When the connecting insulating wall 3a and the secondary insulating wall 5 or the connecting insulating material 32a and the secondary insulating material 51 of the connecting insulating wall 3a are formed in this thickness ratio, the low temperature of the secondary barrier 4 The upper limit of the stress in , may correspond to 50 MPa or less at the lower portion of the connection insulating wall 3a. In addition, specifically, the stress value at a low temperature of the secondary barrier 4 may be 40 MPa to 50 MPa in the lower portion of the connection insulating wall 3a. These figures were obtained according to the results of structural analysis to be described later.

In this embodiment, the thickness of the connecting insulating wall 3a and the second insulating wall 5 or the thickness of the connecting insulating material 32a and the secondary insulating material 51 of the primary insulating wall 3 is the same or similar. In this regard, it will be described with reference to FIGS. 4 to 20 .

4 (a), (b) is a secondary barrier ( 4) is a diagram showing the tensile force. It is assumed that the total thickness of the connection insulating wall 3a, the secondary barrier 4, the secondary insulating wall 5 and the like in FIGS. 4A and 4B is the same.

On the other hand, the secondary barrier 4 and the secondary insulating wall 5 have a difference in the amount of self-contraction depending on the temperature to which they are exposed. In the case of the secondary barrier 4 and the secondary insulating wall 5, the connection insulating wall 3a ), the thinner the thickness, the more affected by the cooling and heat of cryogenic liquefied gas. In addition, in this case, there is a problem that the secondary barrier 4 is damaged by increasing the stress at low temperature because the temperature itself is lowered and the amount of shrinkage itself is increased. This problem may occur especially in the auxiliary barrier 42 that interconnects the main barrier 41 provided in the unit elements adjacent to each other under the connection insulating wall 3a by bonding or the like. Both ends of the auxiliary barrier 42 are connected to the main barrier 41 of each unit element in the lower portion of the connection insulation wall 3a. As the secondary insulation wall 5 of the unit element contracts, both ends of the auxiliary barrier 42 This is because they can be deformed to move away from or close to each other.

Referring to Figure 4 (a), the connection insulating wall (3a) is formed relatively thinner than the secondary insulating wall (5), the height of the secondary barrier (4) is upward from the center of the total thickness based on the thickness direction. It shows the case where it is located in At this time, in order to reduce the mechanical stress applied to the secondary barrier 4 when the hull is structurally deformed due to the 6 degree of freedom movement of the hull 7, the thickness of the secondary thermal insulation wall 5 is secured 2 The thickness of the heat-blocking wall 5 may be relatively thicker than that of the connection heat-insulating wall 3a.

Referring to Figure 4 (b), the thickness of the connection insulating wall (3a) and the secondary insulating wall (5) are formed similarly, so that the height of the secondary barrier (4) is the central region of the total thickness based on the thickness direction. It shows the case where it is located in Here, the central region may correspond to 40% to 60% of the total thickness. In this case, as compared with (a) of FIG. 4 , the amount of shrinkage itself is reduced, and thus the stress at low temperature will be reduced. In addition, compared with (a) of Figure 4, the risk of damage to the secondary barrier will be relatively low.

In the present invention, a liquefied gas storage tank (1) that can reduce the low-temperature burden and sloshing burden of the secondary barrier (4) while maintaining the mechanical strength of the secondary insulating wall (5) at a certain level has been derived, and the following 5 to 20 will be understood.

5 to 20 are, in order to derive the thickness of the primary insulating wall 3 and the secondary insulating wall 5 encompassing the connection insulating wall 3a of the liquefied gas storage tank 1 according to the present embodiment. Connection insulation wall 3a for each case 1 (Figs. 5 to 8), the second case (Figs. 9 to 12), the third case (Figs. 13 to 16), and the fourth case (Figs. 17 to 20) It is a diagram showing the results of structural analysis while varying the thickness of the and secondary insulating wall 5 . In this embodiment, the thickness of the connecting insulating wall 3a is mainly described, but it should be noted that the thickness of the first insulating wall 3 is also the same as or similar to that of the connecting insulating wall 3a.

In carrying out the structural analysis for each case, the analysis conditions are as follows.

First, the total thickness of the connection insulating wall 3a and the secondary insulating wall 5 of the first to fourth cases, which are the analysis models, was equally applied to 400 mm.

Second, only the position of the secondary barrier 4 was different by varying the thickness of each of the connection insulating wall 3a and the secondary insulating wall 5 .

Third, considering the same linear temperature distribution conditions, the temperature of the primary barrier (2) position was set to -163 °C, which is the temperature of liquefied gas, and the temperature at the hull (7) position was set to room temperature (20 °C).

Fourth, by fixing the minimum and maximum values of the stress values, different stresses are indicated by color, for example, red indicates the greatest stress value, and blue indicates that the stress value is smaller.

Fifth, the thickness ratio was defined as the ratio of the thickness of the connection insulating wall 3a among the total thickness (400 mm).

Structural analysis of case 1 to case 4, which is an analysis model, was performed under the above analysis conditions.

5 to 8 are the first to derive the thickness of the connecting insulating wall (3a) and the second insulating wall (5) encompassed in the primary insulating wall (3) of the liquefied gas storage tank according to the first embodiment of the present invention These are drawings showing the results of structural analysis while varying the thickness of the connection insulating wall (3a) and the secondary insulating wall (5) of the case.

The first case is a case in which the thickness of the connection insulating wall 3a is 100 mm and the thickness of the secondary insulating wall 5 is 300 mm, as shown in FIG. 5 . That is, in the first case, the ratio of the thickness of the connecting insulating wall 3a among the total thickness (400 mm) of the connecting insulating wall 3a and the secondary insulating wall 5 is 0.25, and the secondary barrier 4 is connected It is located close to the primary barrier (2), which is the upper end from the center of the total thickness of the sum of the thicknesses of the insulating wall (3a) and the secondary insulating wall (5).

In the case of this first case, as shown in FIGS. 6 to 8 , as a result of the structural analysis, in a state in which the unit elements are arranged adjacently, a portion of the secondary barrier 4 corresponding between the neighboring secondary insulating walls 5 is It is shown in red, and the stress value was calculated to be 70.12 MPa.

The reason why stress is generated in the secondary barrier 4 in the case of the first case can be seen from FIG. 4 . That is, as the thickness of the connection insulating wall 3a decreases, it is greatly affected by the cooling and heat of the liquefied gas in the secondary barrier 4 .

9 to 12 show the thickness of the connection insulating wall 3a and the secondary insulating wall 5 encompassed by the primary insulating wall 3 of the liquefied gas storage tank according to the first embodiment of the present invention. These are drawings showing the results of structural analysis while varying the thickness of the connection insulating wall 3a and the second insulating wall 5 of the two cases.

The second case is a case in which the thickness of the connection insulating wall 3a is 160 mm and the thickness of the secondary insulating wall 5 is 240 mm, as shown in FIG. 9 . That is, in the second case, the ratio of the thickness of the connecting insulating wall 3a among the total thickness (400mm) of the connecting insulating wall 3a and the secondary insulating wall 5 is 0.4, and the secondary barrier 4 is connected It is located slightly biased toward the primary barrier (2) from the center of the total thickness of the sum of the thicknesses of the insulating wall (3a) and the secondary insulating wall (5).

In the case of this second case, as shown in FIGS. 10 to 12 , as a result of the structural analysis, in a state in which the unit elements are arranged adjacent to each other, the secondary barrier 4 portion corresponding to the adjacent secondary thermal insulation walls 5 is It appeared as a yellow system, and the stress value was calculated to be 55.09 MPa.

13 to 16 show the thickness of the connecting insulating wall 3a and the secondary insulating wall 5 encompassed by the primary insulating wall 3 of the liquefied gas storage tank according to the first embodiment of the present invention. These are drawings showing the results of structural analysis while varying the thickness of the connecting insulating wall 3a and the second insulating wall 5 in three cases.

The third case is a case in which the thickness of the connection insulating wall 3a and the thickness of the secondary insulating wall 5 are identical or similar as shown in FIG. 13 . That is, in the third case, the ratio of the thickness of the connecting insulating wall 3a among the total thickness (400mm) of the connecting insulating wall 3a and the secondary insulating wall 5 is about 0.5, and the secondary barrier 4 is It is located adjacent to the center of the total thickness of the sum of the thicknesses of the connecting insulating wall (3a) and the secondary insulating wall (5).

In the case of this third case, as shown in FIGS. 14 to 16 , as a result of the structural analysis, in a state in which the unit elements are arranged adjacently, the secondary barrier (4) portion corresponding to the adjacent secondary insulating walls (5) is It appeared as a light sky blue system, and the stress value was calculated to be 47.63 MPa.

17 to 20 show the thickness of the connecting insulating wall 3a and the secondary insulating wall 5 encompassed by the primary insulating wall 3 of the liquefied gas storage tank according to the first embodiment of the present invention. These are drawings showing the results of structural analysis while varying the thickness of the connecting insulating wall 3a and the second insulating wall 5 of the four cases.

The fourth case is a case in which the thickness of the connection insulating wall 3a is 240 mm and the thickness of the secondary insulating wall 5 is 160 mm, as shown in FIG. 17 . That is, in the fourth case, the ratio of the thickness of the connecting insulating wall 3a among the total thickness (400 mm) of the connecting insulating wall 3a and the secondary insulating wall 5 is 0.6, and the secondary barrier 4 is connected It is located below from the center of the total thickness of the sum of the thicknesses of the insulating wall (3a) and the secondary insulating wall (5).

In the case of this fourth case, as shown in FIGS. 18 to 20 , as a result of the structural analysis, in a state in which the unit elements are arranged adjacent to each other, the secondary barrier (4) portion corresponding to the adjacent secondary insulating walls (5) is It appeared as a light blue system, and the stress value was calculated as 41.21 MPa.

As described above, as a result of structural analysis of the first to fourth cases, the secondary barrier 4 under the connection insulating wall 3a decreases as the distance from the primary barrier 2 increases, the low-temperature stress due to heat shrinkage decreases. It can be seen that there is a tendency to It will be described with reference to FIG. 21 .

21 is a view showing the relationship between the low-temperature stress of the secondary barrier and the probability of brittle fracture of the hull according to the thickness change of the primary and secondary thermal insulation walls.

As shown in the graph shown in FIG. 21 , in addition to the first to fourth cases, the secondary barrier 4 under the connecting insulating wall 3a is further away from the primary barrier 2, It can be predicted that the resulting stress value will decrease. That is, it can be seen that the secondary barrier 4 under the connection insulating wall 3a decreases as the temperature increases as the distance from the primary barrier 2 increases, so that the shrinkage decreases and the stress decreases. In this embodiment, the secondary barrier 4 under the connecting insulating wall 3a is mainly described, but the secondary barrier 4 under the fixed insulating wall 3b constituting the unit element is also far from the primary barrier 2 It will be obvious that the stress decreases as the temperature increases. The secondary barrier 4 under the connection insulating wall 3a is a state in which the main barrier 41 and the auxiliary barrier 42 are stacked, and the secondary barrier 4 under the primary insulating wall 3 is the main barrier ( 41) consists of only

The liquefied gas storage tank 1 of this embodiment derived in this way increases the thickness of the connecting insulating wall 3a from the total thickness of the sum of the thicknesses of the connecting insulating wall 3a and the secondary insulating wall 5. The temperature received by the barrier 4 rises (reducing the influence of cold heat from the cryogenic liquid gas). Through this, the shrinkage due to the cooling and heating of the secondary barrier 4 itself is reduced, and the stress due to the cooling is reduced, thereby preventing damage to the secondary barrier 4 due to the cooling and heating. Of course, this principle is also applied to the secondary barrier (4) under the primary insulating wall (3) defined as encompassing the connection insulating wall (3a).

In addition, as the thickness of the connecting insulating wall 3a and the fixed insulating wall 3b increases (the thickness of the secondary insulating wall 5 is relatively reduced), the secondary barrier 4 is formed on the secondary barrier 4 The transmitted sloshing load and fluid dynamic load are lowered, and the stress caused by the sloshing is reduced, so that damage caused by the sloshing can be prevented. In addition, as the thickness of the secondary insulating wall 5 decreases (the thickness of the primary insulating wall 3 becomes relatively thick), it may be easy to adjust the flatness of the secondary barrier 4 .

In addition, as the thickness of the connecting insulating wall 3a and the fixed insulating wall 3b is increased, the thickness of the secondary insulating wall 5 is relatively decreased, and since it is relatively farther from the primary barrier 2, the secondary insulating wall The shrinkage force due to the cooling heat of (5) is also reduced, and the tensile force of the secondary barrier 4 is reduced according to the decrease in the contractile force of the secondary thermal insulation wall 5, so that the secondary barrier 4 is the contractile force of the secondary thermal insulation wall 5. damage can be prevented.

Considering the low-temperature stress of the secondary barrier 4, in the present invention, the connecting insulating wall 3a is arranged to correspond to 40% or more in the combined thickness of the connecting insulating wall 3a and the secondary insulating wall 5. can Preferably, the liquefied gas storage tank 1 of the present invention has a thickness in the range of the second to fourth cases, that is, the connecting insulating wall 3a is the sum of the connecting insulating wall 3a and the second insulating wall 5 . It can be arranged to correspond to 40% to 60% of the. More preferably, the liquefied gas storage tank (1) of the present invention is 47% of the range of the third case, that is, the thickness of the connecting insulating wall (3a) is the sum of the connecting insulating wall (3a) and the second insulating wall (5) It can be arranged to correspond to to 53%.

However, if the thickness of the connection insulating wall (3a) and the primary insulating wall (3) is increased, the thickness of the secondary insulating wall (5) is relatively decreased. It is inevitably vulnerable to mechanical stress applied when the hull 7 is structurally deformed due to the island movement, and accordingly, the degree of mechanical stress transmitted to the secondary barrier 4 through the secondary insulating wall 5 increases. have no choice but to

In addition, in the state in which the liquefied gas is loaded, an emergency condition such as the primary barrier 2 is broken may occur. In this case, since the primary barrier 2 can no longer prevent leakage of the liquefied gas, the liquefied gas may come into contact with the secondary barrier 4 . In addition, when the secondary barrier (4) is in contact with the cryogenic liquefied gas, the temperature of the hull (hull) is lowered, the probability of brittle fracture can be increased. In addition, the lower the temperature, the higher the material strength of the hull, but the higher the brittleness problem occurs, the higher the probability of brittle fracture. Here, brittle fracture may correspond to a sudden fracture that occurs with little plastic deformation, and may be understood as a brittle crack.

In this regard, referring to FIG. 21 , in an emergency situation, the secondary barrier 4 contacted with cryogenic liquefied gas from the first case to the fourth case approaches the hull, so the probability of brittle fracture increases. That is, in FIG. 21 , the probability of brittle fracture of the hull increases from the first case to the fourth case, that is, as the thickness of the connection insulating wall increases compared to the thickness of the secondary insulating wall 5 . In addition, when the thickness of the connection insulating wall 3a of the fourth case becomes thicker, the probability of brittle fracture is close to 1 and the hull may be cracked or split.

Therefore, the insulation system of the liquefied gas storage tank 1 should be arranged in consideration of the risk of cracking or destruction of the hull as well as the above-described low-temperature stress. In the present invention, the second to fourth cases in which the secondary barrier 4 is located in the central region of the total thickness of the connection insulating wall 3a and the secondary insulating wall 5 are low-temperature stress and the side of the hull crack Considering all of them, it may be appropriate. Preferably, it can be seen that the third case is appropriate in terms of low temperature stress and mechanical cracks in the hull.

Therefore, the present invention reduces the low-temperature stress of the secondary barrier 4 by sufficiently securing the thickness of the connection insulating wall 3a and the primary insulating wall 3, and by appropriately providing the thickness of the secondary insulating wall 4, the hull (7) and the secondary barrier (4) provided with a gap between the secondary barrier (4) to reduce the burden on the structural stress transmitted from the hull (7), the second to fourth cases are appropriate It can be done by example. In addition, the third case among them will correspond to a preferred embodiment when both aspects of low-temperature stress and mechanical strength are considered.

On the other hand, the material of the secondary barrier 4 may be variously configured, and in this regard, it will be described with reference to FIGS. 22 to 24 .

22, 23 and 24 are views for explaining various configurations of the secondary barrier of the liquefied gas storage tank according to the first embodiment of the present invention.

As shown in FIG. 22 , the secondary barrier 4 may be formed of a first material having a three-layer structure in which a glass fabric (GC)/aluminum foil (AF)/glass-aramid fabric (GAC) is laminated. .

Glass-aramid fabric (GAC) is a glass fabric (Aramid) material applied to the (Aramid) material, it can be manufactured by mixing 1 line of aramid per 2 lines of glass fiber (Glass fiber).

Such a first material may be applied to the auxiliary barrier 42 of the secondary barrier 4, but is not limited thereto, and may be applied to the main barrier 41 of the secondary barrier 4, of course.

As shown in Figure 23, the secondary barrier 4, glass fabric (GC) / aluminum foil (AF) / glass fabric (GC) / aluminum foil (AF) / glass fabric (GC) is laminated 5 layers It may be formed of a second material of the structure.

This second material may be applied to the main barrier 41 of the secondary barrier 4, but is not limited thereto and may also be applied to the auxiliary barrier 42 of the secondary barrier 4, of course.

As shown in FIG. 24, the secondary barrier 4 is made of inorganic basalt fabric extracted from basalt, basalt fabric (BC) / aluminum foil (AF) / basalt fabric (BC) ) may be formed of a third material having a stacked three-layer structure.

This third material may be applied to the main barrier 41 which is the secondary barrier 4, but is not limited thereto, and may be applied to the secondary barrier 42 which is the secondary barrier 4, of course.

22 to 24, the secondary barrier 4 of this embodiment may be formed of various materials having a multi-layer structure in which the first member/aluminum foil (AF)/second member are stacked. At this time, at least one of the first member and the second member is a glass fabric (GC), a glass-aramid fabric (GAC), a basalt fabric (BC), or a glass fabric (GC)/aluminum foil (AF)/glass fabric (GC) ) can be

In addition, of course, various materials applied to the secondary barrier 4 may be applied in various combinations to the main barrier 41 and the auxiliary barrier 42 of the secondary barrier 4 .

25 is a partial cross-sectional view for explaining a right-angled corner structure of a liquefied gas storage tank according to a first embodiment of the present invention, and FIG. 26 is an obtuse-angled corner structure of a liquefied gas storage tank according to a first embodiment of the present invention. Some cross-sectional views for

5 to 20, when the thickness of the connection insulation wall 3a or the first insulation wall 3 and the thickness of the second insulation wall 5 are formed in the same and similar ranges, it is assumed to have a more stable insulation system. Confirmed. For example, in the same or similar range, the position of the secondary barrier 4 is 40% to 60% of the total thickness of the connection insulating wall 3a or the sum of the thickness of the primary insulating wall 3 and the secondary insulating wall 5 It can be shown if it is located in . Such a configuration can be equally applied to the right-angled corner structure of the liquefied gas storage tank 1 shown in FIG. 25 and the obtuse-angled corner structure of the liquefied gas storage tank 1 shown in FIG. 26 .

However, in the right-angled corner structure and the obtuse-angled corner structure of the liquefied gas storage tank (1), the secondary barrier (4) has no choice but to be formed in a curved shape, and when it is formed in a curved shape, it is vulnerable to the load caused by the surrounding environment compared to the straight part, The present embodiment can relieve the stress caused by such a load. In addition, this embodiment may be easy to absorb the hull deformation.

Referring to FIG. 25 , in the right-angled corner structure, the secondary barrier 4 has a radius of curvature of the primary insulating wall 3 as the thickness of the primary insulating wall 3 becomes thicker than the first and second cases. It occupies 25% or more of the thickness, for example, 25% to 50%.

In addition, in the right-angled corner structure, the secondary barrier 4 is, as the thickness of the primary thermal insulation wall 3 becomes thicker than the first and second cases, compared to the existing thin primary thermal insulation wall to the hull 7 side. will move In this case, the radius of curvature increases, and as the radius of curvature increases, the length (L1) of the secondary barrier scab part not glued to the secondary barrier 4 also increases. do. This means an increase in the flexibility of the secondary barrier 4 in the right-angled corner structure, whereby the secondary barrier 4 in the right-angled corner structure absorbs peripheral deformations, for example, hull deformation is facilitated, and low-temperature stress is also reduced. will do For example, the length L1 of the non-adhesive portion may be 100 mm to 200 mm.

Referring to FIG. 26 , the secondary barrier 4 in the obtuse corner structure has a radius of curvature of the primary insulating wall 3 as the thickness of the primary insulating wall 3 becomes thicker than the first and second cases. It occupies 15% or more of the thickness, for example, 15% to 35%.

In addition, in the obtuse-angled corner structure, the secondary barrier 4 is thicker than the first and second cases, and as the thickness of the primary thermal insulation wall 3 becomes thicker than the existing thin primary thermal insulation wall, it is directed toward the hull 7 side. As it moves, the radius of curvature increases. In this case, as the radius of curvature of the secondary barrier 4 increases, the length L2 of the secondary barrier 4 is not glued to the secondary heat insulating wall 5 (secondary barrier scab part not glued) also increases. do. This means an increase in the flexibility of the secondary barrier 4 in the obtuse-angled corner structure, whereby the secondary barrier 4 in the obtuse-angled corner structure absorbs peripheral deformations, for example, hull deformation is facilitated, and low-temperature stress is also reduced. will do For example, the length L2 of the non-adhesive portion may be 50 mm to 90 mm.

As described above, the secondary barrier 4 in the right-angled corner structure and the obtuse-angled corner structure of the present invention is applied to the existing secondary barrier compared to the right-angled corner structure and the obtuse-angled corner structure of the primary insulating wall formed with a relatively thin thickness. Stress at low temperatures can be reduced. In addition, since the non-adhesive portion increases, it is also easy to absorb the hull deformation.

27 is a graph showing thermal conductivity according to the materials used for the primary and secondary insulating materials of the liquefied gas storage tank.

In the liquefied gas storage tank 1 according to the embodiment of the present invention described above, the primary insulating materials 32 and 32a of the connecting insulating wall 3a and the primary insulating wall 3 and the secondary of the secondary insulating wall 5 Each of the insulating materials 51 has been described to be formed of the same polyurethane foam material, but in some cases, polyurethane foams having different materials may be selectively used.

Specifically, the reinforced polyurethane foam (RPUF) is produced by mixing polyol, isocyanate, and a blowing agent, and HFC-245fa or CO ₂ may be used as the blowing agent. HFC-245fa may be relatively expensive compared to CO ₂ .

In the case of this embodiment, the primary insulation material (32, 32a) is formed of a reinforced polyurethane foam using CO ₂ as a foaming agent, and the secondary insulation material 51 is formed of a reinforced polyurethane foam using a foaming agent HFC-245fa. .

Looking at the thermal conductivity characteristics of the blowing agent HFC-245fa and the blowing agent CO ₂ with reference to the graph of FIG. 27, the blowing agent HFC-245fa has a lower thermal conductivity value at room temperature compared to the blowing agent CO ₂ , but the same or similar value toward the cryogenic temperature see.

That is, the thermal conductivity values of the blowing agent HFC-245fa and the blowing agent _{CO 2} show the same or similar values at the temperature below -80 ° C.

Accordingly, in this embodiment, the relatively expensive foaming agent HFC-245fa is not used for both the primary insulation materials 32 and 32a and the secondary insulation material 51, and in consideration of economic aspects, the primary The insulating materials 32 and 32a may be formed of a reinforced polyurethane foam in which CO ₂ is used as a foaming agent, and the secondary insulation 51 may be formed of a reinforced polyurethane foam in which the foaming agent HFC-245fa is used.

28 is a partial cross-sectional view for explaining the liquefied gas storage tank according to the second embodiment of the present invention, Figure 29 is a partial perspective view for explaining the liquefied gas storage tank according to the second embodiment of the present invention.

28 to 29, the liquefied gas storage tank 1 according to the second embodiment of the present invention is a primary barrier 2 in contact with the liquefied gas from the inside, the primary barrier 2 The primary insulating wall 3 and the connecting insulating wall 3a, the primary insulating wall 3 and the connecting insulating wall 3a installed outside the secondary barrier 4, the secondary barrier 4 It may be configured to include a secondary heat insulating wall 5 disposed on the outside and fixed to the hull 7, and the configuration of the connection insulating wall 3a is different from that of the first embodiment described above, and other configurations are the same Or, since they are similar, only the different parts will be described in order to avoid overlapping description hereinafter.

In this embodiment, as compared with the above-described first embodiment, the configuration of the connecting heat insulating wall 3a may be different.

Specifically, as compared with the above-described first embodiment, the connection insulating wall 3a may further include an auxiliary insulating plate 33 .

That is, the connection insulation wall 3a may have a structure in which the connection plywood 31a, the connection insulation material 32a, and the auxiliary insulation plate 33 are stacked.

The auxiliary heat insulating plate 33 may have a thickness of 5 mm to 10 mm, and is made of plywood, high-density polyurethane foam (HD PUF), FRP (Fiber Reinforced Plastic), etc. to obtain a load dispersing effect of the secondary barrier 4 can Alternatively, the auxiliary heat insulating plate 33 may be made of VIP (Vacuum Insulation Panel), LD PUF, or the like having excellent thermal insulation properties to compensate for the insulation vulnerability in the portion where the connection insulating wall 3a is formed.

The thickness of the connecting insulating material 32a of the connecting insulating wall 3a and the primary insulating material 32 of the fixed insulating wall 3b constituting the unit element may be the same. However, in the case of the connection insulating wall (3a), in addition to the main barrier (41) of the secondary barrier (4) at the bottom, the auxiliary barrier (42) is further laminated, and also includes the auxiliary heat insulating plate (33), so the connection insulating wall ( The thickness of the connecting insulating material 32a of 3a) may be smaller than that of the primary insulating material 32 of the primary insulating wall 3 by the thickness of the auxiliary barrier 42 and the thickness of the auxiliary insulating plate 33 .

The auxiliary heat insulating plate 33 described above may be installed not only under the connecting insulating material 32a of the connecting insulating wall 3a but also below the primary insulating material 32 of the primary insulating wall 3 constituting the unit element. to be.

30 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a third embodiment of the present invention, Figure 31 is an enlarged view of a main part of the liquefied gas storage tank according to the third embodiment of the present invention.

30 to 31, the liquefied gas storage tank 1 according to the third embodiment of the present invention is a primary barrier 2 in contact with the liquefied gas from the inside, the primary barrier 2 The primary insulating wall 3 and the connecting insulating wall 3a, the primary insulating wall 3 and the connecting insulating wall 3a installed outside the secondary barrier 4, the secondary barrier 4 The second insulation wall 5 disposed on the outside and fixed to the hull 7, the leveling member 8 installed between the second insulation wall 5 and the hull 7, and the second insulation wall 5 are attached to the hull (7) It may be configured to include a fixing member 9 for fixing to, and the leveling member 8 and the fixing member 9 are different from the first embodiment described above, and other configurations are the same or similar, so that in the following In order to avoid overlapping description, only the leveling member 8 and the fixing member 9, which are components different from those of the first embodiment, and parts that are different therefrom will be described.

The leveling member 8 may be installed between the secondary heat insulating wall 5 and the hull 7 .

The leveling member 8 is a non-adhesive elastic insulating material that can level the deformed portion of the hull 7, increase the thermal insulation performance of the tank, and support the secondary thermal insulation wall 5, and EPS (Expanded Polystyrene) etc.

The leveling member 8, the upper surface in close contact with the secondary heat insulating wall 5 by the elastic force becomes flat, and the lower surface in close contact with the hull 7 may have a curved surface to fit the deformation of the hull 7 . Deformation of the hull 7 may occur, for example, during interblock welding of the hull 7 .

That is, the leveling member 8 can level the deformed portion of the hull without using the existing mastic and leveling wedge. Here, of course, the leveling wedge may be selectively used.

In this embodiment, by applying the leveling member 8 as described above, unlike mastic that is applied in several types according to the size of the existing gap, it can be constructed in a single size, and there is no need for mastic curing time, so the working time can be shortened, and by applying a heat insulating material, it is possible to increase the thermal insulation power.

The fixing member 9 may have a cleat structure including a protrusion 91 and a stud bolt 92 so as to fix the secondary heat insulating wall 5 to the hull 7 .

The protrusion 91 may be provided to protrude from both side lower portions of the unit panel of the second heat insulating wall 5 to the outside, and may be formed of plywood.

The protrusion 91 is fixed over a side surface of the secondary plywood 52 of the secondary heat insulating wall 5 and some side of the secondary insulating material 51 from the secondary plywood 52 to a certain height on one side. It can be installed, the lower surface forms the same level as the lower surface of the secondary plywood (52).

The width and thickness of the protrusions 91 may be such that the stud bolts 92 can be inserted between the protrusions 91 facing each other when a plurality of unit panels constituting the secondary heat insulating wall 5 are disposed.

The stud bolts 92 may be fixed to the hull 7 .

The stud bolts 92 are fixed to the hull 7 so as to match the space between the unit panels of the neighboring secondary heat insulating walls 5 when a plurality of unit panels constituting the secondary insulating wall 5 are arranged. can

The stud bolts 92 are provided on each side of the unit panel of the adjacent secondary thermal insulation wall 5 and are positioned between the two opposing protrusions 91 by tightening the bolts to secure the secondary thermal insulation wall 5 to the hull. (7) can be fixed.

32 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a fourth embodiment of the present invention, and FIG. 33 is a first slit forming a gap between the connection insulating wall and the fixed insulating wall forming the primary insulating wall It is a view for explaining a filling insulation material for filling a plurality of second slits provided on the wall, and FIG. 34 is provided in the first slit and the fixed insulation wall forming a gap between the connection insulation wall and the fixed insulation wall forming the primary insulation wall It is a view for explaining a filling insulation material according to another embodiment for filling a plurality of second slits that become It is a view for explaining a filling insulation material according to another embodiment for filling a plurality of second slits provided in the.

32 to 35, the liquefied gas storage tank 1 according to the fourth embodiment of the present invention includes a primary barrier 2 in contact with liquefied gas from the inside, and a primary barrier 2 A primary insulating wall (3) installed outside of the connecting insulating wall (3a) and a fixed insulating wall (3b), a secondary barrier (4) installed outside the primary insulating wall (3), and a secondary barrier (4) may be configured to include a secondary heat insulating wall (5) disposed on the outside and fixed to the hull (7), compared to the first embodiment described above, the connection insulating wall (3a) and the fixed insulating wall (3b) ), filling the first slit SL1 forming a gap between In order to avoid explanation, we will focus on the parts that change.

The primary thermal insulation wall 3 and the secondary thermal insulation wall 5 of this embodiment may have the same or similar thickness as described above.

The primary insulating wall 3 may include a connection insulating wall 3a and a fixed insulating wall 3b.

When the unit elements including the fixed insulating wall 3b are arranged adjacent to each other, the connecting insulating wall 3a is adjacent to the fixed insulating wall 3b so as to seal a space generated between the neighboring secondary insulating walls 5. It may be inserted between the installation, in this case, a gap may be formed between the connection insulating wall (3a) and the fixed insulating wall (3b).

The first slit SL1 is a gap formed between the connection insulating wall 3a and the fixed insulating wall 3b and may be formed to a depth corresponding to the thickness of the first insulating wall 3 .

In addition, in this embodiment, a plurality of second slits SL2 may be formed in the fixed insulating wall 3b at regular intervals to prepare for contraction and expansion of the fixed insulating wall 3b.

The second slit SL2 may be formed to have a depth similar to the thickness of the fixed insulating wall 3b so that contraction or expansion stress caused by the temperature applied to the fixed insulating wall 3b can be maximally relieved. For example, when the thickness of the fixed insulating wall 3b is 200 mm, the depth of the second slit SL2 may be 185 mm to 195 mm, but is not limited thereto.

The first slit SL1 and the second slit SL2 can prevent damage to the primary heat insulating wall 3 by relieving the contraction or expansion stress caused by temperature, but act as a convection path to act as a secondary barrier ( 4) can increase the low temperature burden.

Accordingly, in this embodiment, by partially or fully filling the first slit SL1 with the first filling insulating material GW1, and partially filling the second slit SL2 with the second filling insulating material GW2, the fixed insulating wall ( To prevent damage due to the contraction and expansion of 3b) and at the same time to reduce the low temperature burden of the secondary barrier 4, it will be described in detail below.

The first filling insulating material GW1 and the second filling insulating material GW2 may be inserted and filled into the first slit SL1 and the second slit SL2 using a jig.

As shown in FIGS. 33 to 35 , the first filling insulating material GW1 is formed to completely fill the first slit SL1 (refer to FIG. 33 ), or a space is created under the first slit SL1 . It is formed to fill from the inlet of the first slit SL1 to a certain depth (see FIG. 34), or is filled in multiple layers inside the first slit SL1 to create a plurality of spaces inside the first slit SL1. It may be formed to do so (see FIG. 35 ).

In addition, as shown in FIGS. 33 to 35 , the second filling insulating material GW2 is formed to be filled to a predetermined depth from the inlet of the second slit SL2 so that a space is created under the second slit SL2 . or (refer to FIGS. 33 and 34), or it may be formed to fill the inside of the second slit SL2 in multiple layers so that a plurality of spaces are created inside the second slit SL2 (refer to FIG. 35).

In the above, the first insulating material GW1 filled in the first slit SL1 and the second insulating material GW2 filled in the second slit SL2 are respectively the first slit SL1 and the second slit SL2. ) can be formed to have a (+) tolerance to completely seal the space in the state of being filled in the space, thereby absorbing contraction and expansion.

Referring to FIG. 33 , the first filling insulation material GW1 may be formed to completely fill the first slit SL1 , and the second insulation insulation material GW2 may be formed to form a space under the second slit SL2 . It may be formed to fill from the entrance of the second slit SL2 to a predetermined depth.

The first charging insulating material GW1 and the second charging insulating material GW2 may be formed of glass wool, but are not limited thereto.

In the above, by forming the first filling insulating material GW1 to completely fill the first slit SL1, it is possible to improve the thermal insulation performance at the connection portion of the connection insulating wall 3a and the fixed insulating wall 3b. The second filling insulating material GW2 is formed to have a space under the second slit SL2, so that the heat insulation performance of the fixed insulating wall 3b is improved by the second filling insulating material GW2, as well as the second It is possible to absorb the contraction and expansion of the fixed insulating wall 3b in the space portion of the slit SL2.

Referring to FIG. 34 , the first filling insulating material GW1 may be formed to be filled to a predetermined depth from the entrance of the first slit SL1 so that a space is created under the first slit SL1 , and the second filling insulating material The GW2 may be formed to fill the second slit SL2 to a predetermined depth from the entrance of the second slit SL2 so that a space is created under the second slit SL2 .

The first charging insulating material GW1 and the second charging insulating material GW2 may be formed of glass wool, but are not limited thereto.

In the above, the first charging insulating material GW1 is formed to have a space under the first slit SL1, so that the connection insulating wall 3a and the fixed insulating wall 3b by the first charging insulating material GW1 are formed. In addition to improving the thermal insulation performance in the connection portion, it is possible to absorb the contraction and expansion of the connection insulation wall 3a and the fixed insulation wall 3b in the space portion of the first slit SL1. The second filling insulating material GW2 is formed to have a space under the second slit SL2, so that the heat insulation performance of the fixed insulating wall 3b is improved by the second filling insulating material GW2, as well as the second It is possible to absorb the contraction and expansion of the fixed insulating wall 3b in the space portion of the slit SL2.

Referring to FIG. 35 , the first filling insulating material GW1 may be formed to be filled in multiple layers so as to create a plurality of spaces inside the first slit SL1, and the second filling insulating material GW2 may be formed in the second slit ( SL2) may be formed to be filled in multiple layers to create a plurality of spaces inside.

The first filling insulating material GW1 is spaced apart from the first upper insulating material GW1-1 formed on the upper portion of the first slit SL1 and the first upper insulating material GW1-1 by a predetermined distance to the first slit. The first intermediate filling insulating material GW1-2 formed in the middle of the SL1 and the first lower filling insulating material GW1-2 formed in the lower portion of the first slit SL1 spaced apart from the first intermediate filling insulating material GW1-2 by a predetermined distance It may be made of the insulator (GW1-3).

Each of the first upper filling insulation material GW1-1, the first intermediate filling insulation material GW1-2, and the first lower filling insulation material GW1-3 may be formed of the same insulation material or different insulation materials, and in this case, the insulation material is used as the insulation material. Glass wool, super light (super lite), soft foam (foam) material, airgel blanket (aerogel blanket) and the like may be used.

The second filling insulating material GW2 is spaced apart from the second upper insulating material GW2-1 formed on the upper portion of the second slit SL2 and the second upper insulating material GW2-1 by a predetermined distance to the second slit. The second intermediate filling insulating material GW2-2 formed in the middle of the SL2, and the second intermediate filling insulating material GW2-2 spaced apart from each other by a predetermined interval, the second lower filling formed under the second slit SL2 It may be made of the heat insulating material GW2-3.

Each of the second upper filling insulation material GW2-1, the second intermediate filling insulation material GW2-2, and the second lower filling insulation material GW2-3 may be formed of the same insulation material or different insulation materials, and in this case, the insulation material is used as the insulation material. Glass wool, super light (super lite), soft foam (foam) material, airgel blanket (aerogel blanket) and the like may be used.

In the above, the first filling insulating material GW1 is formed in multiple layers so as to have a plurality of spaces inside the first slit SL1, so that the multi-layered first filling insulating material GW1-1, GW1-2, GW1-3) In addition to improving the thermal insulation performance at the connection portion of the connecting insulating wall 3a and the fixed insulating wall 3b by the 3b) to absorb the contraction and expansion. The second filling insulating material GW2 is formed so that a plurality of spaces are created inside the second slit SL2, so that the fixed insulating wall is formed by the multi-layered second insulating material GW2-1, GW2-2, GW2-3. In addition to improving the thermal insulation performance of (3b), it is possible to absorb the contraction and expansion of the fixed thermal insulation wall 3b in a plurality of space portions of the second slit SL2.

36 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a fifth embodiment of the present invention, FIG. 37 is a cross-sectional view of a connection insulating wall cut along the line A-A' of FIG. It is a cross-sectional view of a unit element formed by laminating the secondary insulating wall, the secondary barrier, and the fixed insulating wall forming the primary insulating wall cut along the line B-B', and FIGS. 39 and 40 are the connecting insulating wall and the fixed insulation forming the primary insulating wall. It is a view for explaining a filling insulating material filling the first slit forming a gap between the walls, and FIGS. 41 and 42 are views showing the structural analysis results of the liquefied gas storage tank according to the fifth embodiment of the present invention, FIG. 43 to 46 show the structure of the slit in the liquefied gas storage tank according to the fifth embodiment and the liquefied gas storage tank according to the comparative example, and convection paths and secondary barriers that vary depending on whether or not a filling insulation filling the slit is applied. It is a diagram for explaining the temperature comparison, and FIG. 47 is a secondary under the slit according to the presence or absence of a filling insulation material for filling the slit in the liquefied gas storage tank according to the fifth embodiment of the present invention and the liquefied gas storage tank according to the comparative example. This is a graph comparing the temperature of the barrier.

36 to 40, the liquefied gas storage tank 1 according to the fifth embodiment of the present invention includes a primary barrier 2 in contact with liquefied gas from the inside, and a primary barrier 2 A primary insulating wall (3) installed outside of the connecting insulating wall (3a) and a fixed insulating wall (3b), a secondary barrier (4) installed outside the primary insulating wall (3), and a secondary barrier (4) disposed on the outside and may be configured to include a secondary heat insulating wall 5 fixed to the hull 7, and compared with the above-described fourth embodiment, the connection insulating wall 3a and the fixed insulating wall 3b ), the first filling insulating material GW1 filling the first slit SL1 forming a gap between Since they are similar, the different parts will be mainly described below in order to avoid overlapping descriptions.

The primary thermal insulation wall 3 and the secondary thermal insulation wall 5 of this embodiment may have the same or similar thickness as described above.

The primary insulating wall 3 may be composed of a connecting insulating wall 3a and a fixed insulating wall 3b, wherein the connecting insulating wall 3a is adjacent to the unit elements including the fixed insulating wall 3b. At this time, it may be inserted between the adjacent fixed heat insulating walls (3b) to seal the space portion generated between the adjacent secondary heat insulating walls (5). In this case, a gap may be formed between the connection insulating wall 3a and the fixed insulating wall 3b.

The first slit SL1 is a gap formed between the connection insulating wall 3a and the fixed insulating wall 3b and may be formed to a depth corresponding to the thickness of the first insulating wall 3 .

In addition, in this embodiment, a plurality of second slits SL2 may be formed in the fixed insulating wall 3b at regular intervals to prepare for contraction and expansion of the fixed insulating wall 3b. At least one second slit SL2 may be formed not only in the longitudinal direction of the fixed insulating wall 3b but also in the width direction as shown in FIG. 38 .

In addition, in the present embodiment, at least one third slit SL3 may be formed in the connection insulating wall 3a to prepare for contraction and expansion of the connection insulating wall 3a. The third slit SL3 is not formed in a relatively narrow width direction, but at least one or more third slits SL3 may be formed in a relatively long length direction as shown in FIG. 37 . The third slit SL3 formed in the longitudinal direction is to be positioned on the same line as the second slit SL2 formed in the longitudinal direction when the connection insulating wall 3a is inserted between the fixed insulating walls 3b. can

In the above, the second slit SL2 is about half the thickness of the fixed insulating wall 3b so as to secure thermal insulation performance while relieving contraction or expansion stress caused by the temperature applied to the fixed insulating wall 3b. It can be formed to a depth corresponding to the thickness of, and the filling insulation is not filled inside. For example, when the thickness of the fixed insulating wall 3b is 200 mm, the depth of the second slit SL2 may be about 90 mm, but is not limited thereto, and may be formed within a range of 100 mm to 50 mm. The third slit SL3 may be formed similarly or identically to the second slit SL2 .

When the first slit SL1 , the second slit SL2 , and the third slit SL3 are not filled with any filling insulating material, as shown in the structural analysis result shown in FIG. 41 , the second slit formed to a shallow depth is It can be seen that the thermal insulation performance is lowered in the fixed insulating wall 3b and the connecting insulating wall 3a near the first slit SL1 having a deeper depth than the fixed insulating wall 3b in which the slit SL2 is formed. This is because a large amount of convection occurs through the deep first slit SL1 .

Accordingly, in this embodiment, by partially filling the first slit SL1 with the first filling insulating material GW1, as shown in the structural analysis result shown in FIG. 42, the first filling insulating material GW1 prevents thermal convection and deep Thermal insulation similar to the thermal insulation performance of the fixed insulating wall 3b in the vicinity of the first slit SL1 formed to a depth and the second slit SL2 formed to a shallow depth in the fixed insulating wall 3b and the connection insulating wall 3a performance can be seen. That is, it can be seen that when the first charging insulating material GW1 is filled in the first slit SL1, the low temperature transfer depth is flattened in all parts.

In the present embodiment, the first charging insulating material GW1 filled in the first slit SL1 has a thickness of the fixed insulating wall 3b or the connection insulating wall 3a so as to improve the thermal convection phenomenon through the slit. It should be formed to be at least longer than the depth of the second slit SL2 or the third slit SL3 which is formed to a depth corresponding to about half the thickness.

Specifically, the convection path formed by the spatial portion of the first slit SL1 in which the first insulating material GW1 is partially filled is the convection path formed by the spatial portion of the second slit SL2 of the fixed insulating wall 3b. And when connected to the convection path formed by the spatial portion of the third slit SL3 of the connection insulating wall 3a, the thermal convection phenomenon is increased, so the path to the first charging insulating material GW1 to prevent the thermal convection phenomenon have to block

For example, when the depth of the second slit SL2 and the third slit SL3 is 90 mm, when the first insulating material GW1 is formed to a length of 80 mm from the inlet of the first slit SL1, 10 mm A connection path of the insulator must be formed, and accordingly, the first charging insulating material GW1 must be formed to have a length of at least 90 mm or more so as to block the connection path.

In addition, as shown in FIG. 40 , the first charging insulating material GW1 of this embodiment uses an adhesive member 10 to both sides of the connection insulating wall 3a opposite to the side surface of the fixed insulating wall 3b. can be attached to

Conventionally, after installing the connecting insulating wall 3a between the adjacent fixed insulating walls 3b, the first charging insulating material GW1 is inserted and installed using a jig, but in this embodiment, the first charging insulating material GW1 is Since the connection insulating wall 3a attached to both sides can be directly inserted between the adjacent fixed insulating walls 3b, installation man-hours can be reduced. At this time, the first charging insulating material GW1 attached to the fixed insulating wall 3b is in a compressed state (reduced in volume) before the connection insulating wall 3a is inserted between the adjacent fixed insulating walls 3b and installed. maintained, and after installation, the compression is released (the volume is increased), so that the first slit SL1 can be completely blocked.

Although it has been described above that the first filling insulating material GW1 of this embodiment is partially filled in the first slit SL1, the same as the first filling insulating material GW1 of the fourth embodiment described with reference to FIGS. After attaching to both sides of the connecting insulating wall 3a with the adhesive member 10 in variously formed states such as similarly formed, the connecting insulating wall 3a can be inserted and installed between the adjacent fixed insulating walls 3b of course there is

Hereinafter, with reference to FIGS. 43 to 47, the connection insulating wall 3a and the fixed insulating wall 3b in the liquefied gas storage tank 1 according to the present embodiment and the liquefied gas storage tank 1 ′ according to the comparative example. ), the convection path that varies depending on the structure of the slit formed in the slit and the presence or absence of the filling insulation filling the slit, and the resulting temperature difference will be described in comparison.

43 (a) and 45 show the liquefied gas storage tank 1 according to the present embodiment, the connection insulating wall 3a and the fixed insulating wall 3b are the same as the above-described configuration. As for the right-angled corner structure and the obtuse-angled corner structure, the ones shown in FIGS. 25 and 26 are applied, but the present invention is not limited thereto, and other right-angled corner structures and obtuse-angled corner structures may be applied.

43 (b) shows a liquefied gas storage tank 1 ′ according to a comparative example, in comparison with the liquefied gas storage tank 1 according to the present embodiment, the first slit SL1 ′ has the same depth, but There is a difference in that the first filling insulating material GW1 is not filled, and the second slit SL2' is formed to have a depth similar to the thickness of the fixed insulating wall 3b. may be the same or similar.

Figure 44 (a) shows the first, second, and third convection paths (CP1, CP2, CP3) in the liquefied gas storage tank (1) according to the present embodiment.

The first convection path CP1 is a path corresponding to the first slit SL1, which is a gap formed between the connection insulating wall 3a and the fixed insulating wall 3b, and is formed in the upper part of the first slit SL1. It can be seen that as the convection blocking path CP1 ′ is formed by the first charging insulating material GW1 , the path is formed only through the lower space portion of the first slit SL1 .

The second convection path CP2 is a path corresponding to the second slit SL2 formed to a depth corresponding to about half the thickness of the fixed insulating wall 3b, and is a space of the second slit SL2. It can be seen that although the path is formed by the portion, the portion of the first charging insulating material GW1 filled in the first slit SL1 is blocked.

The third convection path CP3 is a path corresponding to the third slit SL3 formed to a depth corresponding to about half the thickness of the connection insulating wall 3a, and is a space of the third slit SL3. It can be seen that although the path is formed by the portion, the portion of the first charging insulating material GW1 filled in the first slit SL1 is blocked.

Figure 44 (b) shows the fourth, fourth, and sixth convection paths (CP4, CP5, CP6) in the liquefied gas storage tank (1') according to the comparative example.

The fourth convection path CP4 is a path corresponding to the first slit SL1', which is a gap formed between the connection insulating wall 3a and the fixed insulating wall 3b, and unlike the present embodiment, the first slit ( It can be seen that a path is formed in all spatial portions of the first slit SL1' as the filling insulating material is not filled in SL1'.

The fifth convection path CP5 is a path corresponding to the second slit SL2' formed to a depth similar to the thickness of the fixed insulating wall 3b, and is a fifth convection path formed as a space portion of the second slit SL2'. It can be seen that the convection path CP5 is connected to the fourth convection path CP4 formed by the space portion of the first slit SL1 ′.

The sixth convection path CP6 is a path corresponding to the third slit (not shown) formed to a depth similar to the thickness of the connection insulating wall 3a, and is a sixth convection path formed by the space portion of the third slit ( It can be seen that CP6) is connected to the fourth convection path CP4 and the fifth convection path CP5.

As described above, in the liquefied gas storage tank 1 of this embodiment, it can be seen that the convection area is reduced while the first, second, and third convection paths CP1, CP2, CP3 are discontinuous with each other, and the liquefied gas storage of the comparative example It can be seen that in the tank 1', the convection area is increased while the fourth, fourth, and sixth convection paths CP4, CP5, and CP6 are continuous.

In addition, as shown in Figure 44 (b), the liquefied gas storage tank (1 ') of the comparative example, each of the fourth, fifth, and sixth convection paths (CP4, CP5, CP6) is a secondary from the primary barrier (2) Since a convection space is formed up to the barrier (4), the temperature at the primary barrier (2) directly affects the secondary barrier (4), resulting in severe temperature drop in the secondary barrier (4). On the other hand, in the liquefied gas storage tank 1 of this embodiment, each of the first, second, and third convection paths CP1, CP2, CP3 has a temperature at the primary barrier 2 by the first charging insulation GW1. It is possible to prevent conduction to the secondary barrier (4), and the temperature drop occurs less in the secondary barrier (4) of the liquefied gas storage tank (1) of this embodiment compared to the liquefied gas storage tank (1') of the comparative example. .

Due to this convection path difference, a temperature difference is also generated in the secondary barrier 4 of each of the liquefied gas storage tank 1 of this embodiment and the liquefied gas storage tank 1' of the comparative example.

45 and 46, when the unit elements are arranged adjacent to each other, a temperature sensor TL is attached so as to be close to the secondary barrier 4 in the space generated between the neighboring secondary insulating walls 5. did.

As a result of measuring the temperature through the temperature sensor (TL) in a state where the temperature of the primary barrier 2 is -196 degrees and the temperature of the hull 7 is 10 degrees, in the liquefied gas storage tank 1 of this embodiment, -79.3 It was -100.9 degrees in the liquefied gas storage tank (1') of the comparative example. As described above, it can be seen that the convection path of the liquefied gas storage tank 1 of this embodiment compared to the liquefied gas storage tank 1' of the comparative example is discontinuous and the convection area is reduced.

Figure 47 is a first slit (SL1') in the liquefied gas storage tank (1') of the comparative example compared to that in which the first filling insulating material (GW1) is filled in the first slit (SL1) in the liquefied gas storage tank (1) of this embodiment ) is a graph comparing the temperature of the secondary barrier 4 under the first slits SL1 and SL1' when the filling insulation is not filled in the .

When the temperature of the primary barrier 2 is -196 degrees and the temperature of the hull 7 is 10 degrees, when the height of the first slits SL1 and SL1' is 0.2mm, the first charging insulation material GW1 is charged The temperature of the secondary barrier 4 under the first slit SL1 of this embodiment was about -90 degrees (graph A), and the secondary barrier under the first slit SL1 ′ of the comparative example in which the filling insulation was not filled. The temperature of the barrier 4 was about -150 degrees (graph B).

Through this, it can be seen that the temperature drop occurs less (prevention of thermal convection) in the secondary barrier 4 of the liquefied gas storage tank 1 of this embodiment compared to the liquefied gas storage tank 1 ′ of the comparative example.

48 is a partial cross-sectional view for explaining a liquefied gas storage tank according to a sixth embodiment of the present invention, FIG. A cross-sectional view of a unit element formed by laminating the secondary insulating wall, the secondary barrier, and the fixed insulating wall constituting the primary insulating wall cut along the line B-B' It is an enlarged view showing a state in which the filling insulating material is filled in the first slit forming the gap.

48 to 51, the liquefied gas storage tank 1 according to the sixth embodiment of the present invention includes a primary barrier 2 in contact with liquefied gas from the inside, and a primary barrier 2 A primary insulating wall (3) installed outside of the connecting insulating wall (3a) and a fixed insulating wall (3b), a secondary barrier (4) installed outside the primary insulating wall (3), and a secondary barrier (4) may be configured to include a secondary heat insulating wall (5) disposed on the outside and fixed to the hull (7), compared to the above-described fifth embodiment, the connection insulating wall (3a) and the fixed insulating wall (3b) ) Since the step portions ST1 and ST2 formed on each side are different, and other configurations are the same or similar, the different parts will be mainly described in order to avoid overlapping description below.

The primary thermal insulation wall 3 and the secondary thermal insulation wall 5 of this embodiment may have the same or similar thickness as described above.

The primary insulating wall 3 may be composed of a connecting insulating wall 3a and a fixed insulating wall 3b, wherein the connecting insulating wall 3a is adjacent to the unit elements including the fixed insulating wall 3b. At this time, it may be inserted between the adjacent fixed heat insulating walls (3b) to seal the space portion generated between the adjacent secondary heat insulating walls (5).

The connection insulating wall 3a, as shown in FIGS. 48 and 49, can be divided into an upper part and a lower part, and the front, rear, left, right, and left widths of the upper part are narrower than the front, rear, left, right, and right widths of the lower part, and thus the connection insulating wall ( A positive first step portion ST1 may be formed on the front, rear, left and right sides of 3a).

The upper and lower portions of the connecting insulating wall 3a may be divided based on a position of about half the thickness of the connecting insulating wall 3a, but is not limited thereto, and a depth similar to the thickness of the connecting insulating wall 3a It may be determined according to the depth of the third slit SL3 formed by , which will be described later. Here, at least one third slit SL3 is formed in the longitudinal direction of the connecting insulating wall 3a, and is formed in the longitudinal direction when the connecting insulating wall 3a is inserted between the fixed insulating walls 3b. The second slit SL2 may be positioned on the same line.

In addition, as shown in FIGS. 48 and 49 , a negative chamfer CH may be formed at the bottom edge of the connection insulating wall 3a.

The chamfer CH serves to facilitate insertion when the connection insulating wall 3a is installed between the adjacent fixed insulating walls 3b.

The fixed insulating wall 3b, as shown in FIGS. 48 and 50, can be divided into an upper part and a lower part, and the front, rear, left, and right widths of the upper part are narrower than the front, rear, left, right, and left widths of the lower part, and thus the fixed insulating wall ( A positive second step portion ST2 may be formed on the front, rear, left, and right sides of 3b).

The upper and lower portions of the fixed insulating wall 3b may be divided based on a position of about half the thickness of the fixed insulating wall 3b, but is not limited thereto, and a depth similar to the thickness of the fixed insulating wall 3b It may be determined according to the depth of the second slit SL2 formed by , which will be described later.

In the above, the first step portion ST1 and the second step portion ST2 may have the same or similar shape, and when the connection insulation wall 3a is inserted between the adjacent fixed insulation walls 3b, A space is defined while facing each other to form a first slit SL1 in which the first charging insulating material GW1 is filled between the connection insulating wall 3a and the fixed insulating wall 3b.

That is, the first step portion PS1 is formed by forming the front, rear, left and right widths of the upper portion to be narrower than the front, rear, left, and right widths of the lower portion when the connection insulating wall 3a is divided into an upper portion and a lower portion, and the second step portion PS2 ), when the fixed insulating wall 3b is divided into an upper part and a lower part, the front, rear, left and right widths of the upper part are narrower than the front, rear, left, right, and right widths of the lower part. By installing so that the lower part of 3a) and the lower part of the fixed insulating wall 3b are adjacent to each other, the space provided between the upper part of the connection insulating wall 3a and the upper part of the fixed insulating wall 3b is filled in the first slit SL1. can be The first charging insulating material GW1 filled in the first slit SL1 may be formed to have a (+) tolerance to completely seal the space in a state in which the space of the first slit SL1 is filled. Due to this, a thermal convection path does not occur in the first slit SL1 even when the connection insulating wall 3a and the fixed insulating wall 3b contract and expand.

For example, in order to insert the first filling insulating material GW1 having a thickness of 10 mm into the first slit SL1, the width of the first slit SL1 is the minimum in consideration of the compression state of the first filling insulating material GW1. Since it should be about 6 mm, in this embodiment, the width between the lower side of the connecting insulating wall 3a and the lower side of the fixed insulating wall 3b is 2 mm (generally the distance between the connecting insulating wall and the fixed insulating wall). The width of the first step portion ST1 provided on the connection insulating wall 3a is 2 mm, and the width of the second step portion ST2 provided on the fixed insulation wall 3b is 2 mm. can do. Since the thickness of the first charging insulating material GW1 filling the first slit SL1 may be varied, the width of each of the first step portion ST1 and the second step portion ST2 of the present embodiment may also vary. is of course

In the present embodiment, the depths of the first step portion ST1 and the second step portion ST2 forming the first slit SL1 are about compared to the thickness of the fixed insulation wall 3b or the connection insulation wall 3a. When the second slit SL2 or the third slit SL3 formed to a depth corresponding to about half the thickness is not formed, the second slit SL2 or the third slit SL3 is not particularly limited. When formed, they need to be limited to prevent tropical convection events.

That is, as described above in the fifth embodiment, in order to prevent the thermal convection phenomenon through the slit, the first charging insulating material GW1 filled in the first slit SL1 is formed by the second slit SL2 or the third slit. Considering that it should be formed to be at least longer than the depth of the SL3, the depth of the first slit SL1 in which the first insulating material GW1 of this embodiment is filled is the second slit SL2 and the third slit ( It should be formed deeper than the depth of SL3).

For example, when the depth of the second slit SL2 and the third slit SL3 in which the filling insulating material is not filled is 90 mm, the depth of the first slit SL1 in which the first filling insulation material GW1 is filled is at least It should be formed to a depth of at least 90 mm, for example 105 mm.

52 is a perspective view for explaining a liquefied gas storage tank according to a seventh embodiment of the present invention, and FIGS. It is a view showing the plane, side, and cross section of the unit element in which the fixed insulating wall is stacked, and FIGS. It is a view, and FIGS. 55 (a) to (c) are views showing the plane, side, and cross-section of a connection insulating wall according to another embodiment constituting the primary insulating wall of FIG. 52, and FIG. 57 is a rear perspective view of a connection insulating wall according to another embodiment constituting the insulating wall, and FIG. 57 is a view showing a cross-section of a portion in which the fixed insulating wall and the connecting insulating wall constituting the primary insulating wall are alternately connected, and FIG. 58 FIG. is a view showing a cross-section of a portion in which a plurality of connection insulation walls constituting a primary insulation wall are continuously connected.

In the above, FIG. 53(c) is a cross-sectional view of the connection insulating wall cut along the line A-A' in FIG. 53(a), and FIG. 54(c) is along the line B-B' in FIG. 55 (c) is a cross-sectional view of the connection insulating wall cut along the line C-C' in FIG. 55 (a).

52 to 58, the liquefied gas storage tank 1 according to the seventh embodiment of the present invention is installed on the outside of the primary barrier and the primary barrier in contact with the liquefied gas from the inside and is connected The primary thermal insulation wall 3 consisting of the thermal insulation wall 3a and the fixed thermal insulation wall 3b, the secondary barrier 4 installed on the outside of the primary thermal insulation wall 3, and the secondary barrier 4 It may be arranged and configured to include a secondary heat insulating wall 5 fixed to the hull 7, and is formed on each side of the connection insulating wall 3a and the fixed insulating wall 3b compared to the fifth embodiment described above It is different to finish the stepped portions PS1, PS2, PS3, PS4 and the stepped portions PS1, PS2, PS3, PS4 with the insulating pads IP1, IP2, and other configurations are the same or similar. In order to avoid explanation, we will focus on the parts that change.

The primary thermal insulation wall 3 and the secondary thermal insulation wall 5 of this embodiment may have the same or similar thickness as described above.

The primary insulating wall 3 may be composed of a connecting insulating wall 3a and a fixed insulating wall 3b, wherein the connecting insulating wall 3a is adjacent to the unit elements including the fixed insulating wall 3b. At this time, it may be inserted between the adjacent fixed heat insulating walls (3b) to seal the space portion generated between the adjacent secondary heat insulating walls (5). Hereinafter, the front, rear, left and right sides of the fixed insulating wall 3b are defined as sides connected to the front and rear sides of the connecting insulating wall 3a, and the left and right sides of the connecting insulating wall 3a are adjacent to the other connecting insulating wall 3a. It is defined as the side connected to the left or right side of

The fixed insulating wall 3b may be divided into an upper portion and a lower portion, as shown in FIGS. 52 and 53 (a) to (c). The upper and lower portions of the fixed insulating wall 3b may be divided based on a position of about half the thickness of the fixed insulating wall 3b, but is not limited thereto.

The fixed thermal insulation wall 3b has an upper front, rear, left, and right width that is narrower than a front, rear, left, right, and right width of the lower part, so that a positive first step portion PS1 may be formed on the front, rear, left, and right side surfaces.

The first step portion PS1 includes a second step portion PS2, a third step portion PS3, or a fourth step formed in a connection insulation wall 3a, which will be described later, on the front, rear, left and right sides of the fixed insulation wall 3b. 57 , the first slit SL1 may be formed by overlapping the front and rear side surfaces of the part PS4 . A first heat insulating pad IP1 may be adhesively formed on the first stepped portion PS1 of the fixed heat insulating wall 3b, and the first heat insulating pad IP1 will be described later.

As shown in FIGS. 52, 54 (a) to (c) and (a) to (c) of FIGS. 56 (a) to (c), the connection insulating wall 3a may be divided into an upper part and a lower part. The upper and lower portions of the connection insulating wall 3a may be divided based on a position of about half the thickness of the connection insulating wall 3a, but is not limited thereto.

The connection insulating wall 3a is inserted and installed in the linear space portion generated between the two adjacent fixed insulating walls 3b, and as shown in (a) to (c) of FIG. 54, the upper The front and rear widths are wider than the front and rear widths of the lower part, and the upper left and right widths are narrower than the lower left and right widths, so that the second step portions PS2 may be formed on the front and rear left and right side surfaces.

The second step portion PS2 has a positive shape on the left and right sides of the connection insulating wall 3a as shown in (b) of FIG. 54, and as shown in (c) of FIG. A negative shape can be achieved from the front and rear sides of 3a).

In the second step portion PS2 having a positive shape on the left and right sides of the connection insulation wall 3a, a plurality of other connection insulation walls are continuous in a linear space portion generated between two adjacent fixed insulation walls 3b. When inserted and installed, the fourth slit SL4 may be formed as shown in FIG. 58 by overlapping the step portion formed in a negative shape on the side of the other adjacent connection insulating wall. A second heat insulating pad IP2 may be formed on the second step portion PS2 having a positive shape on the left and right side surfaces of the connection heat insulating wall 3a, and the second heat insulating pad IP2 will be described later. Here, the other connection insulating wall is a connection insulating wall 3a having a negative third step part PS3 on one side, as shown in FIG. 55(b), or as shown in FIG. 56, It may be a connection insulating wall 3a having a negative fourth step portion PS4 in the depressions on the front, rear, left, and right sides.

The second step portion PS2, which forms a negative shape on the front and rear side surfaces of the connection insulating wall 3a, is inserted between two adjacent fixed insulating walls 3b and is installed on the front, rear, left and right sides of the fixed insulating wall 3b. 57 , the first slit SL1 may be formed by overlapping the first step portion PS1 having a positive shape in FIG. 57 .

In addition, the connection insulating wall 3a is inserted and installed in a linear space portion generated between two adjacent fixed insulating walls 3b, and as shown in (a) to (c) of FIG. 55, The front and rear width of the upper part is formed wider than the front and rear width of the lower part, and the left and right widths of the upper part are formed to be the same as the left and right widths of the lower part, but are formed alternately on the left and right sides. have.

As shown in (b) of FIG. 55, one side of the third step portion PS3 has a negative shape and the other side has a positive shape among the left and right sides of the connection insulating wall 3a, as shown in (b) of FIG. 54 (c) ), a negative shape may be formed in the front and rear sides of the connection insulating wall 3a.

In the third step portion PS3 forming a negative shape among the left and right side surfaces of the connection insulation wall 3a, a plurality of other connection insulation walls are continuous in a linear space generated between two adjacent fixed insulation walls 3b. When inserted and installed, the fourth slit SL4 may be formed by overlapping the step portion formed in a positive form on the side surface of the other adjacent connection insulating wall, as shown in FIG. 58 . Here, the other connection insulating wall is a connection insulating wall 3a having a positive second step part PS2 on the left and right sides, as shown in FIG. 54(b), or shown in FIG. 55(b). As described above, it may be a connection insulating wall 3a having a positive third step portion PS3 on the other side thereof.

In the third step portion PS3 having a positive shape among the left and right side surfaces of the connection insulation wall 3a, a plurality of other connection insulation walls are continuous in a linear space generated between two adjacent fixed insulation walls 3b. When inserted and installed, the fourth slit SL4 may be formed as shown in FIG. 58 by overlapping the step portion formed in a negative shape on the side of the other adjacent connection insulating wall. A second heat insulating pad IP2 may be formed on the third step portion PS3 having a positive shape among the left and right side surfaces of the connection heat insulating wall 3a. The second heat insulating pad IP2 will be described later. Here, the other connection insulating wall is a connection insulating wall 3a having a negative third step part PS3 on one side, as shown in FIG. 55(b), or as shown in FIG. 56, It may be a connection insulating wall 3a having a negative fourth step portion PS4 in the depressions on the front, rear, left, and right sides.

In addition, the connection insulating wall 3a is inserted and installed in the intersecting space portion generated between the four adjacent fixed insulating walls 3b, and as shown in FIG. It is formed to be wider than the front, rear, left, and right widths, and the fourth step portion PS4 may be formed on the front, rear, left, and right side surfaces.

The fourth step portion PS4 may have a negative shape in the protrusions on the front, rear, left, and right sides of the connection insulating wall 3a and the depressions on the front, rear, left, and right sides.

The fourth step portion PS4, which forms a negative shape in the protrusions on the front, rear, left, and right sides of the connecting insulation wall 3a, is inserted into the space portion of the cross shape that occurs between the four adjacent fixed insulation walls 3b When installed, 58, the fourth slit ( SL4) can be formed. Here, the other connection insulating wall is a connection insulating wall 3a having a positive second step part PS2 on the left and right sides, as shown in FIG. 54(b), or shown in FIG. 55(b). As described above, it may be a connection insulating wall 3a having a positive third step portion PS3 on the other side thereof.

The fourth step portion PS4, which has a negative shape in the depressions on the front, rear, left and right sides of the connecting insulation wall 3a, is inserted and installed in the space portion of the cross shape that occurs between the four adjacent fixed insulation walls 3b. , overlaps with the first step portion PS1 forming a positive shape on the front, rear, left and right sides of each of the four adjacent fixed insulating walls 3b, to form a first slit SL1, as shown in FIG. 57 . have.

As shown in FIG. 57, the first slit SL1 of the present embodiment is formed by inserting the connection insulating wall 3a between the adjacent fixed insulating walls 3b. A space formed between the fixed insulating wall 3b and the connecting insulating wall 3a by overlapping the first negative step formed on the side surface of the connection insulating wall 3a on the first positive step formed on the side surface. has a gin form. Here, the first positive step portion formed on the side surface of the fixed insulation wall 3b may be a positive first step portion PS1 formed on the front, rear, left and right sides of the fixed insulation wall 3b, and the connection insulation wall 3a ) formed on the side of the first negative step portion is a second step portion (PS2), a third step portion (PS3) formed on the front and rear sides of the connection insulating wall (3a), or the front, rear, left and right side surfaces of the connection insulation wall (3a) It may be the fourth step portion PS4 formed in the recessed portion of the .

In the first slit SL1 having the curved shape, the thermal convection phenomenon is reduced compared to the slit having the straight shape, but the thermal convection phenomenon may occur through the space of the first slit SL1 .

Accordingly, in this embodiment, the first insulating pad IP1 is adhesively formed on the first step portion PS1 formed in a positive shape on the front, rear, left, and right sides of the fixed insulating wall 3b to prevent the thermal convection phenomenon. do.

The first insulating pad IP1 may be adhesively formed on a first positive step portion formed on a side of the fixed insulating wall 3b facing the connection insulating wall 3a, and the connection insulating wall 3a is adjacent to the first insulating pad IP1. When installed between the fixed insulating walls 3b, the first negative step is formed on the side facing the fixed insulating wall 3b in the connecting insulating wall 3a without being adhered to the connecting insulating wall 3a. may be compressed to block the space portion of the first slit SL1 .

The first heat insulating pad IP1 may be formed of a heat insulating material such as glass wool, but is not limited thereto.

In addition, as shown in FIG. 58 , the fourth slit SL4 of the present embodiment is one of the connection insulation walls among the adjacent connection insulation walls 3a when a plurality of connection insulation walls 3a are continuously installed. A space formed between the adjacent connecting insulating walls 3a by overlapping the second negative step formed on the side of the other connecting insulating wall 3a on the second positive step formed on the side of (3a). , has a curved shape. Here, the second positive step portion formed on the side surface of any one of the connection insulation walls 3a is a second step portion PS2 and a third step portion formed on at least one side of the left and right side surfaces of the connection insulation wall 3a. (PS3), the second negative step formed on the side of the other connecting insulating wall 3a is a third step formed on at least one of the left and right sides of the connecting insulating wall 3a (PS3) Alternatively, it may be a fourth step portion PS4 formed on the protrusions of the front, rear, left, right, and right sides of the connection insulating wall 3a.

In the fourth slit SL4 having the curved shape, the thermal convection phenomenon is reduced compared to the slit having the straight shape, but the thermal convection phenomenon may occur through the space of the fourth slit SL4 .

Accordingly, in the present embodiment, in order to prevent the thermal convection phenomenon, a second positive step is formed on the second positive step part or the second negative step part formed on the left and right sides of the adjacent connection insulating wall 3a. The heat insulating pad IP2 is adhesively formed.

The second insulating pad IP2 may be adhesively formed on the second positive step portion formed on the side surface of any one of the connection insulating walls 3a among the neighboring connection insulating walls 3a. When the (3a) is continuously installed between the adjacent fixed insulating walls 3b, it is compressed by the second negative step formed on the side of the other connecting insulating wall 3a among the neighboring connecting insulating walls 3a. As a result, the space portion of the fourth slit SL4 may be blocked.

The second heat insulating pad IP2 may be formed of a heat insulating material such as glass wool, but is not limited thereto.

In the present embodiment described above, the width of each of the first, second, third, and fourth step portions PS1, PS2, PS3, and PS4 may be the same or similar, for example, may be 30 mm, but is limited thereto not.

In addition, the width of each of the first and fourth slits SL1 and SL4 may be the same or similar, for example, the width between the upper side of the connection insulating wall 3a and the upper side of the fixed insulating wall 3b This is 2 mm, and the width between the lower side of the connection insulating wall 3a and the lower side of the fixed insulating wall 3b may be 2 mm, but is not limited thereto.

In addition, the thickness and width of each of the first and second heat insulating pads IP1 and IP2 may be the same or similar, for example, the thickness may be 10 mm and the width may be 30 mm, but is not limited thereto.

As described above, in this embodiment, the thickness of the primary thermal insulation wall 3 and 3a from the total thickness of the primary thermal insulation wall 3 and the secondary thermal insulation wall 5 encompassing the connection thermal insulation wall 3a is the secondary thermal insulation wall 5. By configuring the same or similar to, it is possible to maintain the mechanical strength of the secondary barrier 5 at a certain level, as well as reduce the low temperature burden and the sloshing burden of the secondary barrier 4, ) to prevent damage.

In addition, in this embodiment, by providing an auxiliary heat insulating plate 33 on the lower surface of the connection insulating wall 3a provided in the space between the adjacent primary insulating walls 3 constituting the unit element, the adjacent 2 It is possible to further increase the thermal insulation performance at the connection portion of the barrier thermal wall 5 .

In addition, the present embodiment can improve the configuration of the secondary barrier 4 to increase the thermal insulation performance.

In addition, in this embodiment, by applying a non-adhesive elastic insulating material as the leveling member 8 of the secondary insulating wall 5 between the secondary insulating wall 5 and the hull 7, the existing mastic and leveling wedge are not used. Even if it is not, it is possible to level the deformed portion of the hull 7, and it is possible to increase the thermal insulation performance of the tank.

In addition, in this embodiment, a cleat structure by a protrusion 91 provided to protrude to the outside on the lower side of the unit panel of the secondary heat insulating wall 5 and a stud bolt 92 fixed to the hull 7 . By fixing the unit panel of the adjacent secondary insulating wall 5 in this way, it is possible to reduce the man-hour compared to the method of fixing the unit panel with stud bolts by punching a hole in the secondary insulating wall 5 .

In addition, this embodiment optimizes the slit provided to prepare for the contraction and expansion of the primary thermal insulation wall 3 formed on the secondary barrier 4, and the convection phenomenon and the secondary barrier ( 4) By improving the slit structure and configuring a variety of filling insulation materials to fill the slits so as to minimize heat penetration to 4) It is possible to reduce the burden of low temperature of the barrier (4), it is possible to prevent damage to the primary insulating wall (3) and the secondary barrier (4).

The present invention is not limited to the embodiments described above, and a combination of the embodiments or a combination of at least one of the embodiments and a known technology may be included as another embodiment. For example, the embodiment of FIGS. 28 to 29 can be combined with the embodiment of FIGS. 4 to 27 . Also, for example, the embodiment of FIGS. 30 to 31 can be combined with the thermal insulation system of FIGS. 1 and 2 or the thermal insulation system of FIGS. 28 and 29 . Also, for example, combinations of the embodiment of FIGS. 32 to 58 with the embodiment of FIGS. 1 to 31 can be combined.

Although the present invention has been described in detail through specific examples, it is intended to describe the present invention in detail, and the present invention is not limited thereto. It will be clear that the transformation or improvement is possible.

All simple modifications or changes of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be made clear by the appended claims.

1, 1': liquefied gas storage tank 2: primary barrier
21: flat part 22: curved part
23: boundary part 3: primary thermal insulation wall
3b: fixed insulation wall 31: primary plywood
32: primary insulation material 3a: connection insulation wall
31a: connecting plywood 32a: connecting insulation material
33: auxiliary insulation plate 4: secondary barrier
41: main barrier 42: auxiliary barrier
GAC: Glass-aramid fabric AF: Aluminum foil
GC: Glass fabric BC: Basalt fabric
5: Second insulation wall 51: Second insulation material
52: secondary plywood 6: mastic
7: Hull 8: Leveling member
9: fixing member 91: protrusion
92: stud bolt 10: adhesive member
SL1, SL1': first slit SL2, SL2': second slit
SL3: third slit SL4: fourth slit
GW1: first filling insulation GW1-1: first filling insulation material
GW1-2: first intermediate filling insulation material GW1-3: first lower filling insulation material
GW2: Second filling insulation material GW2-1: Second filling insulation material
GW2-2: Second intermediate filling insulation material GW2-3: Second lower filling insulation material
CP1: first convection path CP1': convection blocking path
CP2: 2nd convection path CP3: 3rd convection path
CP4: 4th convection path CP5: 5th convection path
CP6: 6th convection path TL: Temperature sensor
ST1: first step portion ST2: second step portion
CH: Chamfer IP1: 1st Insulation Pad
IP2: 2nd insulation pad PS1: 1st step part
PS2: 2nd step PS3: 3rd step
PS4: 4th step

Claims (4)

A liquefied gas storage tank for storing cryogenic substances consisting of a primary barrier, a primary insulating wall, a secondary barrier, and a secondary insulating wall,
The first insulating wall,
In a state in which the unit elements formed by stacking the secondary insulating wall, the secondary barrier, and the fixed insulating wall that are part of the primary insulating wall are arranged adjacent to each other, a connection insulating wall provided in a space between the adjacent fixed insulating walls including,
a first step portion formed on front, rear, left, and right sides of the connection insulating wall;
a second step portion formed on front, rear, left, and right sides of the fixed insulating wall;
a first slit formed by the first step portion and the second step portion between the connection insulation wall and the fixed insulation wall when the connection insulation wall is inserted between the adjacent fixed insulation walls; and
A liquefied gas storage tank including a first filling insulating material for filling the first slit. According to claim 1, wherein the first step portion,
It is made by forming the front, rear, left and right widths of the upper part of the connection insulating wall to be narrower than the front, rear, left and right widths of the lower part of the connecting insulating wall,
The second step portion,
It is made by forming the front, rear, left and right widths of the upper portion of the fixed insulating wall to be narrower than the front, rear, left and right widths of the lower portion of the fixed insulating wall,
The first charging insulating material,
A liquefied gas storage tank filled in the first slit, which is a space provided between the upper part of the connection insulating wall and the upper part of the fixed insulating wall, by installing the lower part of the connection insulating wall and the lower part of the fixed insulating wall adjacent to each other. 3. The method of claim 2,
a plurality of second slits formed in a longitudinal direction and a width direction of the fixed insulating wall; and
At least one or more third slits are formed in the longitudinal direction of the connecting insulating wall and positioned on the same line as the second slit formed in the longitudinal direction when the connecting insulating wall is inserted between the fixed insulating walls. do,
The second slit and the third slit are
It is formed to a depth corresponding to a thickness of about half of the thickness of the fixed insulating wall and the connection insulating wall, and the filling insulating material is not filled therein;
The first slit in which the first charging insulating material is filled,
formed to be at least longer than a depth of each of the second slit and the third slit,
A liquefied gas storage tank in which a thermal convection path through the first slit, the second slit and the third slit is discontinuous. The method according to claim 1, wherein the first heat insulating wall and the second heat insulating wall are,
Liquefied gas storage tanks having the same or similar thickness.

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