KR102608691B1 - Insulation System of Liquefied Natural Gas Storage Tank - Google Patents

Abstract

An insulation system for a liquefied natural gas storage tank is disclosed. The insulation system for a liquefied natural gas storage tank according to the present invention is a liquefied natural gas storage tank including an insulation wall made of a plurality of insulation panels and a sealing wall installed on the insulation wall to seal the liquefied natural gas, A transverse connector installed at the corner of the tank to support the sealing wall and transfer the load applied to the sealing wall to the hull; An insulation box installed at the corner of the storage tank to support the transverse connector; And a space insulation member is inserted into the gap formed between the insulation box and the insulation panel (border panel) disposed closest to the corner of the storage rack, and the plurality of insulation panels include insulation and plywood. It is prepared as a sandwich panel made of a composite of, the border panel is made of polyurethane foam with a higher density than the rest of the insulation panels, and the space insulation member is prepared to have the average heat shrinkage of the insulation box and border panel, so that the storage tank of the storage tank It is characterized in that the structural rigidity of the insulating wall is sequentially achieved at the corner portion.

Description

Insulation System of Liquefied Natural Gas Storage Tank {Insulation System of Liquefied Natural Gas Storage Tank}

The present invention relates to an insulation system for a liquefied natural gas storage tank. More specifically, when an insulation system with different rigidity for each section is placed at the corner of a liquefied natural gas storage tank, insulation layers of different shapes (insulation box and This relates to an insulation system for a liquefied natural gas storage tank that effectively prevents damage to the metal membrane by minimizing the difference in steps at the boundary of the insulation panel.

Natural gas is transported in gaseous form through onshore or offshore gas pipelines, or stored in LNG carriers as liquefied natural gas (Liquefied Natural Gas (LNG)) and transported to distant consumers. LNG is obtained by cooling natural gas to extremely low temperatures (approximately -163°C), and its volume is reduced to approximately 1/600 of that of gaseous natural gas, making it very suitable for long-distance transportation by sea.

Structures for transporting or storing LNG, such as LNG carriers that carry LNG on the sea and unload it at land-based destinations, are equipped with storage tanks (commonly referred to as 'cargo holds') that can withstand the extremely low temperatures of LNG.

LNG storage tanks can be classified into independent tank type and membrane type depending on whether the load of the cargo acts directly on the insulation material. Typically, membrane-type storage tanks are divided into GTT's NO 96 type and MARK Ⅲ type, and independent tank-type storage tanks are divided into MOSS type and IHI-SPB type.

Among the membrane-type storage tanks, the NO 96 type storage tank has primary and secondary sealing walls made of an Invar (36% nickel steel) membrane with a thickness of 0.5 to 0.7 mm, and perlite in a plywood box. It includes primary and secondary insulation walls provided in the form of an insulation box filled with insulation materials such as powder.

The NO 96 type storage tank has almost the same level of liquid tightness and strength as the primary sealing wall and the secondary sealing wall, so when the primary sealing wall leaks, the cargo can be safely supported with only the secondary sealing wall for a considerable period of time.

In addition, the NO 96 type storage tank has an insulation wall filled with insulation inside a wooden box, so it can have higher compressive strength and rigidity compared to the MARK Ⅲ type storage tank, and the automation rate is high due to easy welding.

Meanwhile, the MARK III type storage tank has a primary sealing wall made of a 1.2mm thick stainless steel (SUS) membrane, a secondary sealing wall made of triplex, and a top surface of polyurethane foam or It includes primary and secondary insulation walls made of insulation panels with wood plywood glued to the bottom.

The primary sealing wall of the MARK III type storage tank has wave-shaped wrinkles to absorb heat contraction caused by LNG in a cryogenic state, and these wave-shaped wrinkles absorb membrane deformation, so no significant stress is generated within the membrane.

However, the MARK Ⅲ type storage tank has the disadvantage of being less stable than the NO 96 type storage tank because it is difficult to apply a stainless steel membrane with a corrugated structure to the secondary sealing wall due to interference with the insulation wall, so it uses a triplex structure.

The MARK Ⅲ type storage tank has a disadvantage in terms of installation/manufacturing due to the low welding automation rate of the primary sealing wall with corrugations, but compared to the Invar membrane, the stainless steel membrane and triplex are cheaper and easier to construct, and polyurethane Because foam has an excellent insulation effect, it is widely used with NO 96 type storage tanks.

The technical problem to be achieved by the present invention is that when an insulation system with different rigidity for each section is placed at the corner of a liquefied natural gas storage tank, a step occurs at the boundary between insulation layers of different shapes (insulation box and insulation panel). The aim is to provide an insulation system for a liquefied natural gas storage tank that can effectively prevent damage to the metal membrane by minimizing damage.

In order to achieve the above object, the present invention provides a liquefied natural gas storage tank comprising an insulating wall made of a plurality of insulating panels and a sealing wall installed on the insulating wall to seal the liquefied natural gas, wherein the storage tank A transverse connector installed at a corner of the tank to support the sealing wall and transfer the load applied to the sealing wall to the hull; an insulation box installed at a corner of the storage tank to support the transverse connector; And a space insulation member inserted into the gap formed between the insulation box and the insulation panel (hereinafter referred to as 'border panel') disposed closest to the corner of the storage tank among the insulation panels, and the plurality of insulation panels. The panel is prepared as a sandwich panel made of a composite of insulation and plywood, and the border panel is made of polyurethane foam with the same or relatively high density as the remaining insulation panels, and the space insulation member is formed between the insulation box and the border. It provides an insulation system for a liquefied natural gas storage tank, which is provided to have an average amount of thermal contraction of the panel, and is characterized in that the structural rigidity of the insulation wall is sequentially achieved at the corner portion of the storage tank of the storage tank.

The space insulation member may include an insulation material having a direction perpendicular to the direction of the insulation material constituting the insulation panel.

The insulation material constituting the insulation panel and the insulation material constituting the space insulation member are provided with either polyurethane foam (PUF) or fiber-reinforced polyurethane foam (R-PUF), and the insulation material constituting the space insulation member is The in-plane direction may be formed in a direction perpendicular to the inner wall of the storage tank.

The insulation material constituting the border panel and the space insulation material is made of fiber-reinforced polyurethane foam with a density of 170 kg/m ³ or more, and the insulation material constituting the remaining insulation panels excluding the border panel is fiber-reinforced with a density of 130 kg/m ³ or more. It may be prepared from polyurethane foam.

The gap formed between the insulation box and the border panel may be 5 to 20 times larger than the gap formed between the insulation panels adjacent to each other.

It further includes an insulation panel connection part filled with glass wool or polyurethane foam insulation in the gap formed between the insulation panels adjacent to each other or provided as an empty space, and the space insulation member is 1.2 to 4 times the size of the insulation panel connection part. The ship can have material rigidity in the thickness direction.

In addition, in order to achieve the above object, the present invention includes a secondary insulation wall consisting of a plurality of secondary insulation panels arranged on the inner wall of the hull, a secondary sealing wall installed on the secondary insulation wall, and the secondary insulation wall. In the liquefied natural gas storage tank including a primary insulation wall made of a plurality of primary insulation panels arranged on the sealing wall, and a primary sealing wall installed on the primary insulation wall, a corner portion of the storage tank a transverse connector installed to support the primary sealing wall and the secondary sealing wall and transmit the load applied to the primary sealing wall and the secondary sealing wall to the hull; and an insulation box supporting the transverse connector, wherein the insulation box includes a primary corner box disposed adjacent to the primary insulation panel at the level of the primary insulation wall, and the secondary insulation wall. It includes a secondary corner box disposed adjacent to the secondary insulation panel at the level, and the secondary corner box is positioned higher than the primary corner box so that the primary insulation panel and the secondary insulation panel are intersected by each other. It protrudes further to the outside of the transverse connector, and provides an insulation system for a liquefied natural gas storage tank, characterized in that the first corner box and the second corner box are arranged in steps.

The primary insulation panel and the secondary insulation panel may be made of a sandwich panel made of a composite of an insulation material made of polyurethane foam and plywood, and the primary sealing wall and the secondary sealing wall may be made of a metal membrane.

The insulation system of the liquefied natural gas storage tank according to the present invention is disposed in the gap (a) formed between the primary corner box and the primary insulation panel, and includes the primary corner box and the 1 disposed on both sides. A primary space insulation member having the average thermal contraction amount of the secondary insulation panel; And a secondary space disposed in the gap (a') formed between the secondary insulation panel and the secondary corner box, and having an average amount of heat contraction of the secondary corner box and the secondary insulation panel disposed on both sides. It may further include an insulating member.

The primary space insulation member and the secondary space insulation member may include polyurethane foam insulation having a direction perpendicular to the polyurethane foam insulation of the adjacent primary and secondary insulation panels, respectively.

The polyurethane foam insulation included in the primary space insulation member and the secondary space insulation member may be formed in an in-plane direction perpendicular to the inner wall of the storage tank.

The primary space insulation member and the secondary space insulation member may include at least one plywood whose thickness direction coincides with the thickness direction of the insulation layer.

The primary space insulation member and the secondary space insulation member may be provided in a form in which a plurality of plywood plywood boards whose thickness direction matches the thickness direction of the insulation layer are stacked.

According to the present invention, when an insulation system with different stiffness for each section is placed at the corner of a liquefied natural gas storage tank, the average heat shrinkage occurs at the intersection between the insulation panels and the boundary between the insulation layers (insulation box and insulation panel) of different shapes. By arranging the space insulation material to a certain degree, the structural rigidity of the insulation layer at the corner portion of the storage tank is sequentially achieved, which has the effect of minimizing the occurrence of steps due to differences in heat contraction at the boundaries of insulation layers of different shapes.

In addition, according to the present invention, a space insulation material disposed at the boundary between insulation layers of different shapes can be manufactured taking into account the directionality of the materials used in the existing insulation system without adding additional materials, and the area where the space insulation material is placed is of the hull. Since it is a flexible space depending on manufacturing tolerances, the space insulation material can also serve as an insulation material for dimension adjustment.

Figure 1 is a diagram showing an insulation system for a liquefied natural gas storage tank according to a first embodiment of the present invention.
Figure 2 is a diagram showing an insulation system for a liquefied natural gas storage tank according to a second embodiment of the present invention.
Figure 3 is a diagram showing a space insulation member and an insulation panel disposed next to it in the insulation system for a liquefied natural gas storage tank according to a second embodiment of the present invention.
Figure 4 is a diagram showing an insulation system for a liquefied natural gas storage tank according to a third embodiment of the present invention.
Figure 5 is a diagram showing an insulation system for a liquefied natural gas storage tank according to a fourth embodiment of the present invention.

In order to fully understand the present invention, its operational advantages, and the objectives achieved by practicing the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the present invention will be described in detail by explaining preferred embodiments of the present invention with reference to the accompanying drawings. The same reference numerals in each drawing indicate the same member.

In the present invention, the use of the terms 'primary' and 'secondary' refers to the function of primarily sealing or insulating LNG, or the function of secondary sealing or insulating, based on the LNG stored in the storage tank. It was used as a standard for classification.

Additionally, by convention, the terms 'top' or 'above' applied to elements of a tank refer to a direction towards the inside of the tank, regardless of the direction with respect to gravity, and likewise, the terms 'bottom' or 'below' refer to a direction towards the inside of the tank, regardless of the direction with respect to gravity. Regardless of the direction, it points towards the outside of the tank.

Figure 1 is a diagram showing an insulation system of a liquefied natural gas storage tank according to a first embodiment of the present invention, and Figure 2 is a diagram showing an insulation system of a liquefied natural gas storage tank according to a second embodiment of the present invention. 3 is a diagram showing a space insulation member and an insulation panel disposed next to it in the insulation system of a liquefied natural gas storage tank according to the second embodiment of the present invention.

In addition, Figure 4 is a diagram showing an insulation system of a liquefied natural gas storage tank according to a third embodiment of the present invention, and Figure 5 is a diagram showing an insulation system of a liquefied natural gas storage tank according to a fourth embodiment of the present invention. am.

First, referring to FIGS. 1 to 5, the liquefied natural gas storage tank according to the present invention includes a secondary insulation wall 100 consisting of a plurality of secondary insulation panels 110 arranged on the inner wall of the hull (H), and , a primary insulation wall 300 consisting of a secondary sealing wall 200 installed on the secondary insulation wall 100, and a plurality of primary insulation panels 310 arranged on the secondary sealing wall 200. It can be seen that the structure includes a primary sealing wall 400 installed on the primary insulation wall 300.

The primary insulation panel 310 is manufactured as a unit panel in the shape of a hexahedron or more polyhedron, and a plurality of primary insulation panels 310 are arranged in the horizontal and longitudinal directions on the secondary sealing wall 200, thereby providing the primary insulation panel 310. An insulating wall 300 can be formed.

The secondary insulation panel 110 is similarly manufactured as a unit panel in the shape of a hexahedron or more polyhedron, and a plurality of secondary insulation panels 110 are arranged in the horizontal and longitudinal directions on the inner wall of the hull (H) to provide secondary insulation. A wall 100 can be formed.

The primary and secondary insulation panels (310, 110) are plyed on the upper or lower surfaces of the insulation materials (311, 111), such as polyurethane foam (PUF) or fiber-reinforced polyurethane foam (RPUF), or on both the upper and lower surfaces. The protective plates 312 and 112 made of wood or composite material (e.g., fiber-reinforced plastic) may be provided as a sandwich panel to which they are bonded.

The secondary insulation wall 100 may be fixed to the inner wall of the hull (H) with an adhesive such as epoxy mastic or studs, and the primary insulation wall 300 may be attached to the secondary insulation wall 100. With the secondary sealing wall 200 interposed between them, the primary insulation panel 310 is coupled to a securing device provided on the upper part of the secondary insulation panel 110, thereby creating a secondary sealing wall ( 200) can be fixed in close contact with the upper part.

The first and second sealing walls 400 and 200 may be made of a metal membrane.

The primary and secondary sealing walls (400, 200) can be made by selectively adopting any one of various metal materials that are resistant to low-temperature embrittlement, such as Invar, stainless steel (SUS), and aluminum alloy. , can include both flat or corrugated metal membranes.

In the present invention, as a preferred embodiment, the primary sealing wall 400 is made of a corrugated membrane made of stainless steel (SUS), and the secondary sealing wall 200 is made of a flat membrane made of Invar. Provides an insulation system.

The primary sealing wall 400 is in direct contact with and seals the LNG, and may be made of a stainless steel membrane containing a plurality of corrugations formed toward the inside of the storage tank, and the plurality of corrugations formed on the membrane are Absorbs shrinkage caused by cryogenic temperatures and prevents stress from concentrating.

The secondary sealing wall 200 may be made of a flat invar membrane in a flat shape.

In addition, in the liquefied natural gas storage tank according to the present invention, a structure made of Invar steel may be installed at the corner of the storage tank so that the secondary sealing wall 200 is provided with a flat Invar membrane in a flat shape. .

Typically, flat Invar membranes have a low heat contraction coefficient, so it is not appropriate to use an insulation panel made of polyurethane foam and plywood composite as an insulation wall. In order to apply a flat Invar membrane, like a conventional NO 96 type storage tank, the insulation wall supporting the membrane must be composed of an insulation box with low heat shrinkage deformation and high rigidity.

However, in the present invention, by installing a transverse connector (500), a structure made of Invar steel, at the corner of the storage tank, the secondary insulation wall (100) is composed of an insulation panel made of polyurethane foam, It makes it possible to construct the secondary sealing wall 200 as a flat membrane.

Specifically, the transverse connector 500 is a grid-shaped structure installed along the edges of the front and rear walls of the storage tank, and one end is welded to an anchoring bar provided on the inner wall of the hull to maintain the storage tank. It is fixedly installed at the corner, and the other end supports both ends of the primary sealing wall 400 and the secondary sealing wall 200, thereby serving to transmit various loads applied to them to the hull (H).

In this way, a portion of the load applied to the primary and secondary sealing walls (400, 200) is transferred to the hull (H) by the transverse connector (500) installed at the corner of the storage tank, thereby eliminating the flat membrane. It is possible to construct the secondary insulation wall 100, which supports the secondary sealing wall 200, from an insulation panel with weaker rigidity than the insulation box.

Therefore, in the present invention, when installing the secondary sealing wall 200 on the upper part of the secondary insulation wall 100, a welding line can be formed as a straight line, and thus automation of welding is possible, thereby improving productivity. There is an effect.

In addition, in the present invention, insulation performance is improved as the insulation walls 300 and 100 are made of polyurethane foam. The liquefied natural gas storage tank according to the present invention has the same insulation effect while significantly reducing the thickness of the primary and secondary insulation walls, compared to the conventional NO 96 type storage tank in which the insulation wall is provided in the form of an insulation box. You can reap.

Meanwhile, a highly rigid insulating box 510 may be placed inside the transverse connector 500 and between the transverse connector 500 and the hull (H) to support the transverse connector 500. there is. The insulation box 510 may be prepared by filling the inside of a plywood box with an insulation material such as perlite powder or glass wool.

Therefore, the liquefied natural gas storage tank according to the present invention is composed of insulation panels (310, 110) in which most of the insulation walls (300, 100) are made of polyurethane foam, but an insulation box (510) is provided at the corner portion of the storage tank. It has a mixed structure.

However, at this time, the rigidity of the insulation box 510 installed at the corner is high, but the rigidity of the insulation panels 310 and 110 is low, so there is a difference in the degree of heat shrinkage between the insulation box 510 and the insulation panels 310 and 110. .

Therefore, during heat shrinkage by cryogenic LNG, the insulation box 510 and the insulation panels 310, 110 are affected by the difference in structural integrity between the insulation box 510 and the insulation panels 310 and 110, and the thermal load and fluid force of the liquefied gas. 110), a height difference occurs due to heat contraction at the boundary between the insulation walls, and as a result, thermal stress is generated in the sealing walls (400, 200) installed on the insulating walls (300, 100), causing damage to the sealing walls (400, 200). There are concerns.

Hereinafter, the metal of the sealing walls (400, 200) will be removed due to the level difference between the insulation box (510) installed at the corner of the storage tank as described above and the insulation panels (310, 110) installed in areas other than the corner. The technical configuration for preventing damage to the membrane will be examined in detail by dividing it into the first to fourth embodiments.

Embodiment 1

Referring to Figure 1, the insulation system of a liquefied natural gas storage tank according to the first embodiment of the present invention is a secondary insulation wall consisting of a plurality of secondary insulation panels 110 arranged on the inner wall of the hull (H). Primary insulation consisting of (100), a secondary sealing wall 200 installed on the secondary insulation wall 100, and a plurality of primary insulation panels 310 arranged on the secondary sealing wall 200. The wall 300, the primary sealing wall 400 installed on the primary insulation wall 300, and installed at the corner of the storage tank to support the ends of the primary and secondary sealing walls 400 and 200. It includes a transverse connector 500 that does.

A plurality of insulation boxes 510 are disposed inside the transverse connector 500 and between the transverse connector 500 and the inner wall of the hull (H) to support the transverse connector 500.

Here, among the insulation boxes 510 installed to support the transverse connector 500, the insulation boxes 510' and 510 are disposed adjacent to the insulation panels 310 and 110 on the side of the transverse connector 500. '') is defined as a corner box.

The corner boxes 510' and 510'' include a primary corner box 510' placed at the level of the primary insulation wall 300 and a secondary corner box 510 placed at the level of the secondary insulation wall 100. '').

As shown in the drawing, the insulation system of a liquefied natural gas storage tank according to the first embodiment of the present invention includes a primary insulation panel 310 and a secondary insulation wall 100 constituting the primary insulation wall 300. ) has a structure in which the secondary insulation panels 110 constituting the structure are arranged cross-wise.

In addition, the first corner box 510' and the second corner box 510'' can also be arranged to intersect, and for this purpose, the second corner box 510'' is more transverse than the first corner box 510'. It is provided to protrude further to the outside of the connection body 500. That is, the length of the secondary corner box 510'' along the longitudinal direction of the storage tank is manufactured to be longer than the length of the primary corner box 510', so that the primary corner box 510' and the secondary corner box ( 510'') may be arranged in steps.

The insulation system for a liquefied natural gas storage tank according to the first embodiment of the present invention includes primary and secondary corner boxes (510', 510'') arranged to cross each other, and primary and secondary insulation panels (310, By intersecting each other, 110) can effectively prevent damage to the sealing walls 400 and 200 due to steps occurring at the boundary between the insulation box 510 and the insulation panels 310 and 110.

In this embodiment, the insulation panels 310 and 110 may be provided as a sandwich panel in which fiber-reinforced polyurethane foam insulation with a density of 130 kg/m ³ or higher is formed between the upper and lower plywood.

In addition, this embodiment configures the rigidity of the insulation layer disposed on the secondary insulation wall 100 to be equal to or greater than the rigidity of the insulation layer disposed on the primary insulation wall 300 when intersecting, so that the difference in steps can be more effectively minimized. there is.

Second embodiment

Next, referring to FIG. 2, the insulation system of the liquefied natural gas storage tank according to the second embodiment of the present invention includes the same configuration as the first embodiment, but includes a primary corner box 510' and a primary insulation panel. A gap (a) is formed between (310) and a primary space insulation member (320) is additionally placed in the gap (a), and similarly, the secondary corner box (510'') and the secondary insulation panel (110) A gap (a') may be formed therebetween, and a secondary space insulation member 120 may be additionally disposed in the gap (a').

The primary space insulation member 320 is disposed between the primary corner box 510' and the primary insulation panel 310, and may be provided to have an average amount of heat contraction of the two insulation layers 510' and 310.

In addition, the secondary space insulation member 120 is disposed between the secondary corner box 510'' and the secondary insulation panel 110, and is arranged to have an average thermal contraction amount of the two insulation layers 510''. 110. It can be.

That is, in this embodiment, the first and second space insulation members 320 and 120 have the heat shrinkage amount of the first and second corner boxes (510' and 510'') and the first and second insulation panels (310), respectively. , 110), and has a heat contraction amount corresponding to the middle of the heat shrinkage amount, and accordingly has the corner boxes (510', 510'') with the greatest rigidity, space insulation members (320, 120) with intermediate rigidity, and the most Insulating panels 310 and 110 having small rigidity are sequentially arranged.

Therefore, as the structural rigidity of the insulation layer at the corner of the storage tank is sequentially achieved, the insulation height according to the difference in the degree of thermal contraction becomes gentle as it moves from the corner boxes (510', 510'') to the insulation panels (310, 110). Therefore, the step at the connection between the corner boxes (510', 510'') and the insulation panels (310, 110) is minimized, effectively preventing damage to the first and second sealing walls (400, 200). You can.

Meanwhile, plywood and polyurethane foam, which make up the insulation layer, use directional materials. The thermal contraction coefficient for the material and direction of the insulation layer is as follows.

Materials and Directions heat shrinkage coefficient Plywood in-plane direction 6 ×10 ^-6 Plywood thickness direction 25 ×10 ^-6 Fiber-reinforced polyurethane foam in-plane direction 25 ×10 ^-6 Fiber-reinforced polyurethane foam thickness direction 75 ×10 ^-6

Since the insulating box 510 uses the direction in which plywood has high rigidity as a vertical member, the thickness direction shrinkage of the insulating box 510 due to thermal load is dominated by thermal contraction in the in-plane direction of the plywood. Here, the 'in-plane direction' refers to the direction perpendicular to the thickness direction of the material, and refers to the direction of the tangent to the plate surface in a flat plate.

On the other hand, the insulation panels 310 and 110, which are provided in the form of a sandwich panel, use the thickness direction (foaming direction) of the fiber-reinforced polyurethane foam, which is the core material, as the thickness direction of the insulation layer in consideration of strength and insulation performance, so the insulation panels ( 310, 110), the thermal contraction in the thickness direction of the fiber-reinforced polyurethane foam is dominant.

Therefore, the space insulation members 320, 120 constructed at the boundary between the corner boxes 510', 510'' and the insulation panels 310, 110 do not use separate materials, considering that they are at the average level of the two. It can be used as an average system by arranging the in-plane direction of the fiber-reinforced polyurethane foam in the thickness direction of the space insulation members (320, 120), or by stacking and arranging the thickness direction of the plywood in the thickness direction of the insulation layer.

Figure 3 shows various examples of space insulation members 320 and 120 applied to the insulation system of a liquefied natural gas storage tank according to the second embodiment of the present invention.

Referring to (a) of FIG. 3, in this embodiment, the space insulation members 320 and 120 may include insulation materials 321 and 121 formed in the same direction as the thickness direction of the insulation layer, that is, in the vertical direction. there is. At this time, the insulation materials (321, 121) may be provided with polyurethane foam or fiber-reinforced polyurethane foam, and more preferably, like the insulation materials (311, 111) of the insulation panels (310, 110), have a density of 130 kg/m ³ or more. It can be prepared from fiber-reinforced polyurethane foam.

In addition, the space insulation members (320, 120) are plywood (322, 122) adhered to the upper and lower surfaces of the insulation materials (321, 121) whose in-plane direction is formed in a vertical direction, as shown in (b) of FIG. It may further include.

At this time, the directionality (in-plane direction is formed in the same direction as the thickness direction of the insulation layer) of the insulation materials 321 and 121 of the space insulation members 320 and 120 is such that the insulation materials 311 and 111 of the insulation panels 310 and 110 are The excitation direction (the in-plane direction is formed in a direction perpendicular to the thickness direction of the insulation layer) can be perpendicular to each other.

Meanwhile, as shown in (c) of FIG. 3, the space insulation members 320 and 120 according to this embodiment may be made of only plywood 322 and 122. At this time, the plywood (322, 122) constituting the space insulation members (320, 120) may be provided in the form of a stack of multiple plywood plywood boards whose thickness direction matches the thickness direction of the insulation layer, or may be provided in an integrated form. In the embodiment shown in (c) of FIG. 3, the amount of heat shrinkage in the thickness direction of the plywood (322, 122) can be applied at a level similar to the amount of heat shrinkage in the in-plane direction of the insulation materials (321, 121).

As such, in this embodiment, the space insulation members 320 and 120 can be manufactured without adding additional materials by considering the direction of the materials used in the existing insulation system, and they can be manufactured by forming insulation layers (insulation boxes and insulation panels) of different shapes. By placing it at the border, it is possible to minimize the level difference that occurs at the corner of the storage tank.

In the insulation system of the liquefied natural gas storage tank according to the second embodiment of the present invention, the gap (a) formed between the primary corner box 510' and the primary insulation panel 310 is the primary insulation adjacent to each other. The gap may be 5 to 20 times the size of the gap (b) formed between the panels 310, and similarly, the gap (a') formed between the secondary corner box (520') and the secondary insulation panel (110) ) may be provided at an interval 5 to 20 times the size of the gap (b') formed between the secondary insulation panels 110 adjacent to each other.

In addition, the gap (b) formed between adjacent primary insulation panels 310 and the gap (b') formed between adjacent secondary insulation panels 110 are filled with glass wool (glass), polyurethane foam, etc. When the insulating material is filled or the space is narrow, the insulating panel connections 330 and 130 provided in the empty space may be disposed. The primary space insulating member 320 of this embodiment is formed by connecting the primary insulating panels adjacent to each other. The material stiffness in the thickness direction is 1.2 to 4 times higher than that of the insulation panel connection portion 330 disposed between (310), and the secondary space insulation member 120 is positioned between adjacent secondary insulation panels 110. The material rigidity in the thickness direction may be provided to have a physical property of 1.2 to 4 times that of the insulation panel connection portion 130 disposed in.

Since the above-mentioned gap (a, a') may have a flexible space depending on the manufacturing tolerance of the hull, the primary and secondary space insulation members (320, 120) are located in the flexible space of the corresponding area (a, a'). When used appropriately, it can also serve as an insulating material for size adjustment.

Third embodiment

Referring to FIG. 4, the insulation system of the liquefied natural gas storage tank according to the third embodiment of the present invention includes the same configuration as the first embodiment, but includes a corner box 510' among the plurality of insulation panels 310 and 110. , 510'', the stiffness of the insulation panels 310' and 110' arranged adjacent to each other is changed.

In this embodiment and the fourth embodiment described below, the insulation panels 310' and 110' disposed adjacent to the corner boxes 510' and 510'' are defined as border panels, and other than this, the insulation panels 310' and 110' are defined as border panels. The remaining insulation panels 310 and 110 are defined as general insulation panels.

The insulation system of the liquefied natural gas storage tank according to the third embodiment of the present invention is disposed adjacent to the corner box (510', 510'') at the corner of the storage tank among the primary and secondary insulation panels (310, 110). The first and second border panels (310', 110') are prepared with high-density polyurethane foam, which has higher rigidity than the remaining general insulation panels (310, 110).

More preferably, the border panels (310', 110') may be provided as a sandwich panel in which a fiber-reinforced polyurethane foam insulation material with a density of 170 kg/m ³ or higher is formed between the upper and lower plywood, and the general insulation panel (310, 110) can be prepared as a sandwich panel in which fiber-reinforced polyurethane foam insulation with a density of 130 kg/m ³ or more is formed between the upper and lower plywood, as described above.

According to this embodiment, the rigidity gradually decreases from the corner boxes 510' and 510'' to the border panels 310' and 110' and the remaining general insulation panels 310 and 110, and thus the corner box Since the insulation height can be achieved gently according to the difference in the degree of thermal contraction as you move from (510', 510'') to the insulation panels (310, 110), the corner boxes (510', 510'') and the insulation panels (310, 110) ) The step at the connection between the two is minimized, and damage to the first and second sealing walls 400 and 200 can be effectively prevented.

Embodiment 4

Referring to FIG. 5, the insulation system of the liquefied natural gas storage tank according to the fourth embodiment of the present invention includes the same configuration as the third embodiment, but includes a primary corner box 510' and a primary border panel 310. '), a gap (a) is formed between the gaps, and a primary space insulation member (320') is additionally placed in the gap (a), and similarly, the secondary corner box (510'') and the secondary border panel (110') ) may be provided in a structure in which a gap (a') is formed between the gaps and a secondary space insulation member (120') is additionally disposed in the gap (a').

In other words, it can be said that the fourth embodiment of the present invention is constructed by combining the features of the second and third embodiments.

The primary space insulation member 320' is disposed between the primary corner box 510' and the primary border panel 310', and is provided to have an average amount of heat contraction of the two insulation layers 510' and 310'. You can.

In addition, the secondary space insulation member 120' is disposed between the secondary corner box 510'' and the secondary border panel 110', and the average thermal contraction amount of the two insulation layers 510'' and 110' is It can be arranged to have.

The primary and secondary space insulation members 320' and 120' may be configured in the same manner as the primary and secondary space insulation members 320 and 120 shown in FIG. 3.

That is, the primary and secondary space insulation members 320' and 120' are made of an insulating material (polyurethane foam or fiber-reinforced polyurethane foam) whose in-plane direction is the same as the thickness direction of the insulating layer, or are formed on the upper and lower surfaces of the insulating material. It can be provided in either a form in which plywood is glued, or in a form made of plywood whose thickness direction is formed to match the thickness direction of the insulation layer.

However, the first and second space insulation members (320', 120') are prepared to have the average heat contraction amount of the insulation layer of the corner boxes (510', 510'') and border panels (310', 110'). If the insulation material of the border panel (310', 110') is made of fiber-reinforced polyurethane foam with a density of 170 kg/m ³ or higher, the insulation material constituting the space insulation members (320', 120') must also have a density of 170 kg/m ³ or higher. It can be prepared from fiber-reinforced polyurethane foam.

The insulation system for a liquefied natural gas storage tank according to the fourth embodiment of the present invention includes border panels (310', 110') disposed closest to the corners of the storage tank among the plurality of insulation panels (310, 110). Space insulation that has greater rigidity than other general insulation panels (310, 110) and has an average amount of heat shrinkage between corner boxes (510', 510'') and border panels (310', 110'). By applying all structures up to the members 320' and 120', among the various embodiments described in this specification, corner boxes 510' and 510'' and insulation panels 310 and 110 are installed at the corners of the storage tank. ), the effect of minimizing the step that occurs at the connection part can be maximized.

The insulation system for the liquefied natural gas storage tank of the present invention described in the first to fourth embodiments of the present invention includes not only the edge portion (90° corner portion) in the width direction of the storage tank, but also the edge portion in the longitudinal direction of the storage tank. The same can be applied to the part (135° corner part).

The present invention is not limited to the described embodiments, and it is obvious to those skilled in the art that various modifications and changes can be made without departing from the spirit and scope of the present invention. Accordingly, such modifications or variations should be considered to fall within the scope of the claims of the present invention.

100: secondary insulation wall 110: secondary insulation panel
110': Secondary border panel 120: Secondary space insulation member
121: insulation material 122: plywood
200: secondary sealing wall
300: Primary insulation wall 310: Primary insulation panel
310': Primary border panel 320: Primary space insulation member
321: insulation material 322: plywood
400: Primary sealing wall
500: Transverse connector 510: Insulation box
510': 1st corner box 510'': 2nd corner box

Claims (13)

In a liquefied natural gas storage tank comprising an insulating wall made of a plurality of insulating panels and a sealing wall installed on the insulating wall to seal the liquefied natural gas,
A transverse connector installed at a corner of the storage tank to transfer the load applied to the sealing wall to the hull by supporting the sealing wall;
an insulation box installed at a corner of the storage tank to support the transverse connector; and
It includes a space insulation member inserted into the gap formed between the insulation box and the insulation panel (hereinafter referred to as 'border panel') disposed closest to the corner of the storage tank among the insulation panels,
The plurality of insulation panels are provided as sandwich panels made of a composite of insulation and plywood, and the border panel is made of polyurethane foam with the same or relatively high density as the remaining insulation panels,
The space insulation member is provided to have an average thermal contraction amount of the insulation box and the border panel,
The structural rigidity of the insulation wall is sequentially achieved at the corner portion of the storage tank of the storage tank,
The space insulation member is characterized in that it includes an insulation material having a direction perpendicular to the direction of the insulation material constituting the insulation panel.
Insulation system for liquefied natural gas storage tank. delete In claim 1,
The insulation material constituting the insulation panel and the insulation material constituting the space insulation member are provided as either polyurethane foam (PUF) or fiber-reinforced polyurethane foam (R-PUF),
The insulation material constituting the space insulation member is characterized in that the in-plane direction is formed in a direction perpendicular to the inner wall of the storage tank.
Insulation system for liquefied natural gas storage tank. In claim 3,
The insulation material constituting the border panel and the space insulation material is made of fiber-reinforced polyurethane foam with a density of 170 kg/m ³ or more,
The insulation material constituting the remaining insulation panels excluding the border panel is characterized in that it is prepared from fiber-reinforced polyurethane foam with a density of 130 kg/m ³ or more,
Insulation system for liquefied natural gas storage tank. In claim 1,
The gap formed between the insulation box and the border panel is characterized in that it is formed at an interval 5 to 20 times the size of the gap formed between the insulation panels adjacent to each other,
Insulation system for liquefied natural gas storage tank. In claim 5,
It further includes an insulation panel connection part provided in the form of a gap formed between the adjacent insulation panels filled with glass wool or polyurethane foam insulation or as an empty space,
The space insulation member is characterized in that it has a material rigidity in the thickness direction of 1.2 to 4 times that of the insulation panel connection part,
Insulation system for liquefied natural gas storage tank. A secondary insulation wall consisting of a plurality of secondary insulation panels arranged on the inner wall of the hull, a secondary sealing wall installed on the secondary insulation wall, and a plurality of primary insulation panels arranged on the secondary sealing wall. In the liquefied natural gas storage tank comprising a primary insulation wall formed and a primary sealing wall installed on the primary insulation wall,
A transverse connector installed at a corner of the storage tank to support the primary sealing wall and the secondary sealing wall and transmit the load applied to the primary sealing wall and the secondary sealing wall to the hull; and
Includes an insulating box supporting the transverse connector,
The insulation box includes a primary corner box disposed adjacent to the primary insulation panel at the level of the primary insulation wall, and a secondary corner disposed adjacent to the secondary insulation panel at the level of the secondary insulation wall. Includes box,
The secondary corner box protrudes further to the outside of the transverse connector than the primary corner box so that the primary insulation panel and the secondary insulation panel are disposed across each other, so that the primary corner box and the secondary Corner boxes are arranged in steps,
The primary insulation panel and the secondary insulation panel are provided as a sandwich panel made of a composite of an insulation material made of polyurethane foam and plywood,
The primary sealing wall and the secondary sealing wall are made of a metal membrane,
A primary space insulation member disposed in the gap (a) formed between the primary corner box and the primary insulation panel and having an average amount of heat contraction of the primary corner box and the primary insulation panel disposed on both sides. ; and
Secondary space insulation disposed in the gap (a') formed between the secondary insulation panel and the secondary corner box, and having an average amount of heat contraction of the secondary corner box and the secondary insulation panel disposed on both sides. Including more absences,
The primary space insulation member and the secondary space insulation member include a polyurethane foam insulation material having a direction perpendicular to the polyurethane foam insulation material of the adjacent primary insulation panel and secondary insulation panel, respectively.
Insulation system for liquefied natural gas storage tank. delete delete delete In claim 7,
The polyurethane foam insulation included in the primary space insulation member and the secondary space insulation member is characterized in that the in-plane direction is formed in a direction perpendicular to the inner wall of the storage tank,
Insulation system for liquefied natural gas storage tank. In claim 7,
The primary space insulation member and the secondary space insulation member include at least one plywood whose thickness direction coincides with the thickness direction of the insulation layer,
Insulation system for liquefied natural gas storage tank. In claim 12,
The primary space insulation member and the secondary space insulation member are characterized in that a plurality of plywood plywood whose thickness direction coincides with the thickness direction of the insulation layer is provided in a laminated form,
Insulation system for liquefied natural gas storage tank.

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