KR20120013239A - Insulation board and liquefied natural gas storage tank including the same - Google Patents

Abstract

PURPOSE: An insulation board and a LNG cargo containment system having the same are provided to reduce contraction of an insulation board by becoming narrow the width of the insulation board's surface adjacent to LNG because the top width of the insulation board is formed smaller than the bottom width thereof. CONSTITUTION: An insulation board comprises a top insulation board(200), a main secondary barrier(300), and a bottom insulation board(400). The top insulation board is coupled to a primary barrier(100). The main secondary barrier is coupled to the top insulation board. The bottom insulation board is coupled to the main secondary barrier and installed in an inner hull(1). Side walls of the bottom insulation board are inclined obliquely in order to have smaller width of the top surface of the bottom insulation board contacting to the main secondary barrier than the bottom surface thereof contacting to the inner hull.

Description

INSULATION BOARD AND LIQUEFIED NATURAL GAS STORAGE TANK INCLUDING THE SAME

The present invention relates to an insulating board and a liquefied natural gas storage tank comprising the same.

In the case of a liquefied natural gas carrier, a vessel carrying liquefied natural gas (liquefied natural gas, LNG) at cryogenic temperatures is equipped with a tank facility capable of storing and storing liquefied natural gas. The liquefied natural gas carrier is the design of a liquefied natural gas storage tank (CCS) that can be transported while maintaining the cryogenic natural gas is a key technology.

The liquefied natural gas storage tank has a primary barrier positioned at the direct contact with the liquefied natural gas, an upper insulation board positioned on the primary barrier, a secondary barrier positioned on the upper insulation board, and a secondary barrier to maintain the cryogenic temperature. And a lower insulation board positioned and secured to the inner hull, which is a ship structural material.

The upper insulation board and the lower insulation board are made of polyurethane foam, plywood, etc. and keep the inside of the storage tank at a cryogenic temperature so that the liquefied natural gas inside the storage tank does not damage the hull.

However, as the liquefied natural gas is loaded, the cryogenic temperature is reached, and the separation may occur at the interface of the adhesive layer of the primary barrier or the secondary barrier due to the difference in the coefficient of thermal expansion of the insulation board. Or damage to the secondary barrier itself.

Accordingly, the present invention provides an insulating board of a liquefied natural gas storage tank in which damage of the primary barrier or the secondary barrier does not occur even in a cryogenic environment.

The insulation board according to the present invention is an insulation board installed between the primary barrier and the inner hull of the liquefied natural gas storage tank, the upper secondary board is coupled to the primary barrier, the main secondary coupled to the upper insulation board And a lower insulation board coupled to the barrier and the primary secondary barrier, the lower insulation board being installed on the inner hull, wherein the lower insulation board is inclined at an angle so that the upper surface of the primary secondary barrier is narrower than the lower surface of the inner hull. Has sidewalls.

The cross section in the width direction of the lower insulating board may be isosceles trapezoidal.

A width of a lower surface of the lower insulating board that contacts the main secondary barrier may be smaller than a width of the upper surface of the lower insulating board that contacts the main secondary barrier.

The upper insulation board may have sidewalls that are inclined obliquely such that an upper surface of the upper insulation board that contacts the primary barrier has a narrower width than a lower surface of the upper insulation board that contacts the primary barrier.

The width direction cross section of the upper insulation board may be isosceles trapezoidal.

The upper insulation board may have vertical sidewalls such that the upper surface of the upper insulation board and the lower surface of the main insulation barrier have the same width.

The upper insulation board and the lower insulation board may have a hexahedron shape.

The liquefied natural gas storage tank according to an embodiment of the present invention includes a plurality of insulation boards described below adjacent to each other and coupled to the inner hull and a lower connection member positioned between the lower insulation boards of the plurality of insulation boards.

The sidewalls of the lower connection member facing the sidewalls of the lower insulation board may be formed to have the same slope as each other.

The opposite sidewall of the lower insulating member and the sidewall of the lower connection member may be formed to contact each other.

The height of the lower connection member may be formed to be the same as the height of the lower insulation board.

It may further include a secondary secondary barrier formed to cover a portion of the primary secondary barrier formed on the upper surface of the lower insulation board of the insulation board adjacent to each other and the upper surface of the lower connection member.

The secondary secondary barrier may be fixed at both ends by adhesion to a portion of the primary secondary barrier.

The lower surface of the lower connecting member may be adhered by an inner hull and an adhesive, and the adhesive may be an epoxy mastic.

The upper surface of the lower connection member may be adhered to the secondary secondary barrier by an adhesive layer applied to a portion of the lower surface of the secondary secondary barrier.

The adhesive layer may be located at the center of the upper surface of the lower connection member.

It may further include an upper connection board located between the secondary secondary barrier and the primary barrier.

The sidewalls of the upper connection member facing the sidewalls of the upper insulation board may be formed to have the same slope as each other.

The opposite sidewall of the lower insulating member and the sidewall of the lower connection member may be formed to contact each other.

The lower surface of the upper connecting member may be adhesively fixed to both widthwise ends of the secondary secondary barrier.

When the width of the upper surface of the insulation board is formed to be narrower than the width of the lower surface as in the present invention, the width of the surface adjacent to the liquefied natural gas is narrowed, thereby reducing the amount of shrinkage of the adjacent surface.

Therefore, peeling of the insulation board and the secondary barrier due to shrinkage can be minimized.

1 is a schematic cross-sectional view of an insulation board of a liquefied natural gas storage tank according to an embodiment of the present invention.
2 is a schematic cross-sectional view of a liquefied natural gas storage tank formed in accordance with an embodiment of the present invention.
3 is a schematic cross-sectional view of a liquefied natural gas storage tank according to another embodiment of the present invention.
4 is a schematic cross-sectional view of a liquefied natural gas storage tank according to another embodiment of the present invention.
5 and 6 are enlarged views of a portion A of FIG. 3 or 4.
7 is a schematic cross-sectional view of a liquefied natural gas storage tank according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In order to clearly describe the present invention, parts irrelevant to the description are omitted, and like reference numerals designate like elements throughout the specification.

Hereinafter, the insulation board of the liquefied natural gas storage tank according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic cross-sectional view of an insulation board of a liquefied natural gas storage tank according to an embodiment of the present invention.

As shown in FIG. 1, the thermal insulation boards 200 and 400 according to an embodiment of the present invention include sidewalls that are inclined at an angle with respect to the primary barrier 100 or the primary secondary barrier 300.

Specifically, the insulation board includes an upper insulation board 200 and a lower insulation board 400. The upper insulation board 200 and the lower insulation board 400 each have a hexahedral shape, and the width of the lower surface of the upper insulation board 200 which contacts the main secondary barrier 300 of the upper insulation board 200 is in the main secondary barrier 300 of the lower insulation board. It is narrower than the width of the upper surface. Therefore, the lower insulation board 400 is not covered with the upper insulation board 200, and the edge of the lower insulation board 400 is exposed.

The upper insulation board 200 has a sidewall inclined obliquely so that the width of the lower surface contacting the main secondary barrier 300 is wider than the width of the upper surface not contacting the main secondary barrier 300. Therefore, the upper insulation member 24 may have an isosceles trapezoidal in cross-sectional shape.

The lower insulation board 400 has a sidewall inclined at an angle because the width of the upper surface contacting the main secondary barrier 300 is narrower than the width of the lower surface not contacting the main secondary barrier 300. Accordingly, the lower insulating member 42 may have an isosceles trapezoidal in cross-sectional shape.

The upper insulation board 200 includes an upper insulation member protection plate 22 and an upper insulation member 24, and the lower insulation board 400 includes a lower insulation member protection plate 42 and a lower insulation member 44.

The angle θ of the sidewall of the upper insulation member 24 with the main secondary barrier 300 may be 76 ° or more and 90 ° or less, and the sidewall of the lower insulation member 42 may form the primary secondary barrier 300. The angle θ may be greater than or equal to 38 ° and less than or equal to 90 °.

The liquefied natural gas storage tank including the upper insulation board 200 and the lower insulation board 400 will be described in detail with reference to FIG. 2.

2 is a schematic cross-sectional view of a liquefied natural gas storage tank formed in accordance with an embodiment of the present invention.

As shown in Figure 2, the liquefied natural gas storage tank according to an embodiment of the present invention is installed on the inner hull, in order from the inner hull, the primary barrier 100, the upper insulation board 200, the main The secondary barrier 300 and the lower insulation board 400 are arranged in sequence to seal and protect the interior of the liquefied natural gas storage tank. At this time, the lower insulation board is fixed to the hull by the fastening means (12).

Specifically, since the primary barrier 100 is in direct contact with the liquefied natural gas in a cryogenic state of -163 ° C, aluminum alloy, invar, 9% nickel steel, stainless steel sheet, etc., which can respond to stress changes It may be made of a metal material resistant to low temperature brittleness. In addition, the center portion has a plurality of corrugations 8 raised in the center to facilitate expansion and contraction even with repeated temperature changes and load changes of the storage liquid, and the corrugations 8 are formed over the entire primary barrier 100. . A reinforcing member (not shown) may be filled inside the pleats 8. The reinforcing member may be provided inside the wrinkle part 8 to reinforce the strength of the wrinkle part 8.

Adjacent primary barriers 100 may be joined together by welding along their edges.

The upper insulation board 200 includes an upper insulation member protection plate 22 and an upper insulation member 24.

The upper insulation member protection plate 22 may be made of wood such as plywood.

In addition, the upper insulating member 24 may be made of a heat insulating material, for example, a polyurethane foam (polyurethane form) having heat insulating properties.

The upper insulation member 24 has a width of the lower surface in contact with the primary secondary barrier 300 is wider than the width of the upper surface in contact with the primary barrier 100 and has an obliquely inclined sidewall, the cross-sectional shape is an isosceles trapezoidal shape. Achieve.

The primary secondary barrier 300 may comprise at least one of fiber-reinforced composite materials such as stainless steel, aluminum, brass, zinc and glass fibers, for example glass fiber between two facing aluminum foils. It can be formed by attaching a glass-fiber composite.

The lower insulation board 400 includes a lower insulation member 42 and a lower insulation member protection plate 44.

The lower insulation member 42 may be made of the same material as the upper insulation member 24, and may be made of, for example, polyurethane foam.

As shown in FIG. 1, the lower insulating member 42 has a lower surface than the lower surface of the lower insulating board 42 that contacts the main secondary barrier 300. Therefore, the lower heat insulation member 42 has the side wall inclined obliquely with respect to the lower heat insulation member protection plate 44, and a cross-sectional shape forms an isosceles trapezoid shape.

The lower insulating member protection plate may be made of plywood or the like.

The fastening means 12 includes a stud bolt 4 and a nut 5, and a bracket 14 having a through hole located between the lower insulation member protection plate 44 and the hull 1 has a stud bolt 4. The lower heat insulating member protection plate 44 may be fixed to the inner hull 1 by being fixed by the nut 5 through the bottom. The fastening means 12 may further include a damper 15. The damper 15 may be formed of a coil spring that supports the bracket and attenuates the shock when an external shock is transmitted. Although not shown, the lower insulation board 400 may be fixed to the inner hull 1 by using various fixing members (not shown).

An adhesive 7 disposed at regular intervals is positioned between the lower insulation member protection plate 44 and the inner hull 1 to fix the lower insulation member protection plate 44 to the inner hull 1. The adhesive 7 may be an epoxy mastic.

In addition, a level pad 17 may be located to maintain a gap between the inner hull 1 and the lower insulating member protection plate 44. However, the present invention is not limited thereto, and the gap between the inner hull 1 and the lower insulating member protecting plate 44 may be adjusted through various means.

On the other hand, the liquefied natural gas storage tank comprises a plurality of insulating boards, which are connected by a connecting board. This will be described in detail with reference to FIG. 3.

3 is a schematic cross-sectional view of a liquefied natural gas storage tank according to another embodiment of the present invention.

Since most of the configuration is the same as in Fig. 2, only other portions will be described in detail.

Referring to FIG. 3, the liquefied natural gas storage tank includes a plurality of upper insulation boards 200 and a lower insulation board 400, which are connected by a connection board 500 and an auxiliary secondary barrier 600.

The secondary secondary barrier 600 may have the same structure as the primary secondary barrier 300 and, for example, a glass fiber composite may be attached between the two metal foils.

The connection board 500 is positioned between the upper insulation boards 200 to fill the gap between the upper insulation boards 200 and includes an upper connection member 54 and a connection member protection plate 52.

The upper connecting member 54 has a sidewall inclined with respect to the main secondary barrier 300 and is inclined at the same inclination as the sidewall of the upper insulating member 24.

Meanwhile, the lower connection member 700 is positioned between the lower insulation boards 400 and has sidewalls that are inclined with respect to the main secondary barrier 600. The side wall of the lower connecting member 700 has the same slope as the side wall of the lower insulating member 42.

In an embodiment of the present invention, the side wall is contacted without a gap between the upper connecting member 54 and the upper insulating member 24 and between the lower connecting member 700 and the lower insulating member 42. When installed in the hull, a gap may occur between the upper connecting member 54 and the upper insulating member 24 due to the difference in coefficient of thermal expansion. In addition, a gap may be provided between the upper connecting member 54 and the upper insulating member 24 and between the lower connecting member 700 and the lower insulating member 42 from the time of construction.

By forming the inclined side wall as described above, by forming the heat insulating member having an isosceles trapezoidal cross section, it is possible to prevent peeling of the primary secondary barrier due to shrinkage and expansion of the heat insulating member at cryogenic temperatures. In other words, by making the width of the surface adjacent to the cryogenic liquefied natural gas narrower than the width of the surface relatively far from the liquefied natural gas, the shrinkage ratio of the adjacent surface is reduced more than when both surfaces are conventionally formed with the same width. The larger the shrinkage of the insulation member, the greater the likelihood that the primary secondary barrier is peeled off. However, as formed in an isosceles trapezoidal shape as in the embodiment of the present invention, the shrinkage at the portion bonded to the primary secondary barrier is reduced. The likelihood of the car barrier peeling off is reduced.

The height of the lower connecting member 700 may be formed to be the same as the height of the lower insulating member 42. However, the lower insulation member 42 may be formed higher than the lower insulation member 42 to protrude in the hull 1 direction.

4 is a schematic cross-sectional view of a liquefied natural gas storage tank according to another embodiment of the present invention.

Since most of the configuration is the same as in Fig. 3, only other portions will be described in detail.

Referring to FIG. 4, the liquefied natural gas storage tank includes a plurality of upper insulation boards 200 and a lower insulation board 400, which are connected by a connection board 500 and an auxiliary secondary barrier 600.

However, unlike in FIG. 4, the width of the lower surface and the upper surface of the connection board 500 of the connection board 500 are the same, so that the upper connection member 54 may have a sidewall perpendicular to the primary barrier 100. have.

When the side wall of the connection board 500 is inclined as shown in FIG. 3, the width of the surface adjacent to the liquefied natural gas becomes relatively wider than the width of the surface far from the liquefied natural gas, thereby increasing the shrinkage of the adjacent surface. Because there is.

Meanwhile, the lower insulating member 700 is attached to the inner hull 1 and fixed by the adhesive 7 positioned on the inner hull 1 as shown in FIG. 3, or the secondary secondary barrier 600 as shown in FIG. 4. Can be fixed.

This will be described in detail with reference to FIGS. 5 and 6.

5 and 6 are enlarged views of a portion A of FIG. 3 or 4.

5 and 6, the secondary secondary barrier 600 is formed by attaching a glass fiber composite 64b between two opposite metal foils 64a and 64c.

The lower surface of the upper connection member 54 is fixed to both ends of the auxiliary secondary barrier 600 in the width direction by the first adhesive layer 62. At this time, both ends of the lower surface of the upper connection member 54 may be fixed by the secondary secondary barrier 600 and the first adhesive layer 62 to increase the corresponding force to the contraction or expansion. However, the present invention is not limited thereto, and the entire lower surface of the upper connection member 54 may be fixed to the auxiliary secondary barrier 600 by the first adhesive layer 62.

  The first adhesive layer 62 may include at least one of an epoxy resin, a polyurethane resin, a phenol resin, and a polyester resin as a thermosetting adhesive layer. . In addition, the first adhesive layer 62 may include a non-stage prepreg or a thermosetting thin film adhesive. When the first adhesive layer 10 is applied with thermal energy at a temperature of 80 ° C. to 200 ° C., the first adhesive layer 10 is melted in a liquid phase and solidified by cross-linking to form the secondary secondary barrier 600 and the upper connecting member 54. Connect it.

Both ends of the auxiliary secondary barrier 600 are fixed to the primary secondary barrier 300 positioned at both ends of the upper surface of the lower insulation board 400 (see FIG. 3) by the second adhesive layer 66. The second adhesive layer 66 may be made of the same material as the first adhesive layer 62.

Meanwhile, as shown in FIG. 3, when the lower connecting member 700 is fixed to the inner hull 1 with the adhesive 7, the upper surface of the lower connecting member 700 is not fixed as shown in FIG. 5.

However, the lower connection member 700 may not be attached to the inner hull 1 as shown in FIG. That is, as shown in FIG. 6, the lower connection member 700 may be attached to and fixed to the secondary secondary barrier 600 by the third adhesive layer 68.

At this time, the third adhesive layer 68 is preferably formed smaller than the width of the upper surface of the lower connection member 700. That is, since the third adhesive layer 68 is to fix the lower connection member 700 without moving between two neighboring lower insulating boards 400, the third adhesive layer 68 is formed to have a minimum area for fixing. When the third adhesive layer 68 is formed on the entire upper surface of the lower connecting member 700, stress may be concentrated because the lower connecting member 700 may not move at all when shrinkage or expansion occurs. Therefore, in order to allow a certain amount of contraction and expansion, it is possible to leave an unbonded portion toward the edge.

The third adhesive layer 68 is preferably located at the center of the upper surface of the lower connection member 700.

Of course, in the embodiment of FIG. 3, the lower connection member 700 may be fixed by the method of FIG. 6, and in the embodiment of FIG. 4, the lower connection member 700 may be fixed by the method of FIG. 5.

Meanwhile, referring to FIG. 7, the width of the connection board 500 according to an embodiment of the present invention may be larger than that of the connection board 500 of FIGS. 3 and 4. Increasing the width of the connection board 500 may include a slit (S) connected to the surface of the connection board. When the width of the connection board 500 is increased, random breakage occurs due to shrinkage and expansion in the cryogenic environment, which may lead to breakage of the entire connection board 500. Therefore, if the slit (S) is formed at regular intervals it can remove the area where the stretching occurs locally, thereby preventing damage to the connection board due to random breaks.

Of course, the slit S may be formed in the upper connection board 200.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of the invention.

1: hull 4: stud bolt
5: nut 8: wrinkles
12: fastening means 14: bracket
15: damper 20: adhesive member
22: upper insulation member protection plate 24: upper insulation member
42: lower insulating member 44: lower insulating member protective plate
52: connection member protection plate 54: connection member
100: primary barrier 200: upper insulation board
300: primary secondary barrier 400: lower insulation board
500: connection board 600: secondary secondary barrier

Claims (21)

Insulation board installed between the primary barrier inside the liquefied natural gas storage tank and the inner hull,
An upper insulation board coupled to the primary barrier;
A main secondary barrier coupled with the upper insulation board, and
Lower insulation boards coupled to the primary secondary barrier and installed on the inner hull
Including,
And the lower insulating board has a sidewall inclined obliquely such that an upper surface of the lower insulating board which contacts the main secondary barrier has a narrower width than a lower surface of the lower insulating board which contacts the inner hull.
The method of claim 1,
The cross section in the width direction of the lower insulating board is an isosceles trapezoidal shape, characterized in that.
The method of claim 1,
And a width of a lower surface of the upper insulation board that contacts the main secondary barrier is narrower than a width of an upper surface of the lower insulation board that contacts the main secondary barrier.
The method of claim 3, wherein
And the upper insulation board has sidewalls that are inclined obliquely such that an upper surface of the upper insulation board which is in contact with the primary barrier has a narrower width than a lower surface of the upper insulation board which is in contact with the primary secondary barrier.
The method of claim 4, wherein
The cross section in the width direction of the upper insulation board is an isosceles trapezoidal shape, characterized in that.
The method of claim 2,
And the upper insulation board has vertical sidewalls such that an upper surface of the upper insulation board and the lower surface of the primary insulation barrier have the same width.
The method of claim 1,
The upper insulation board and the lower insulation board is a heat insulation board, characterized in that consisting of a cube.
A plurality of insulating boards according to any one of claims 1 to 7 adjacent to each other and coupled to the inner hull and
A liquefied natural gas storage tank comprising a lower connecting member positioned between the lower insulating boards of the plurality of insulating boards.
The method of claim 8,
Liquefied natural gas storage tank, characterized in that the side wall of the lower connecting member facing the side wall of the lower insulating board is formed to have the same slope with each other.
The method of claim 9,
Liquefied natural gas storage tank, characterized in that the side wall of the lower insulating member and the side wall of the lower connecting member is in contact with each other.
The method of claim 10,
The height of the lower connection member is a liquefied natural gas storage tank, characterized in that the same as the height of the lower insulating board.
12. The method of claim 11,
Liquefied natural gas storage tank further comprises a secondary secondary barrier formed to cover a portion of the primary secondary barrier formed on the upper surface of the lower insulation board of the insulation board adjacent to each other and the upper connection member.
The method of claim 12,
The auxiliary secondary barrier is a liquefied natural gas storage tank, characterized in that both ends are fixed to the portion of the main secondary barrier by adhesion.
The method of claim 13,
The lower surface of the lower connecting member is liquefied natural gas storage tank, characterized in that the adhesive by the inner hull and adhesive.
The method of claim 14,
Liquefied natural gas storage tank, characterized in that the adhesive is an epoxy mastic.
The method of claim 13,
The upper surface of the lower connection member is a liquefied natural gas storage tank, characterized in that the adhesion to the secondary secondary barrier by an adhesive layer applied to a portion of the lower surface of the secondary secondary barrier.
17. The method of claim 16,
The adhesive layer is a liquefied natural gas storage tank, characterized in that located in the center of the upper surface of the lower connecting member.
The method of claim 13,
Further comprising an upper connecting board located between the secondary secondary barrier and the primary barrier.
19. The method of claim 18,
Liquefied natural gas storage tank, characterized in that the side wall of the upper connecting member facing the side wall of the upper insulation board is formed to have the same slope with each other.
The method of claim 19,
Liquefied natural gas storage tank, characterized in that the side wall of the lower insulating member and the side wall of the lower connecting member is in contact with each other.
The method of claim 19,
The lower surface of the upper connecting member is liquefied natural gas storage tank, characterized in that fixed to both ends in the width direction of the secondary secondary barrier by adhesion.

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