KR20220087652A - Insulation structure for liquified gas storage tank and method for forming the insulation structure - Google Patents

Abstract

The present invention relates to a heat insulating structure of a liquefied gas storage tank for insulating the liquefied gas stored inside the tank body, comprising: an insulating part formed by spraying and laminating a polymer foam a plurality of times on the outer surface of the tank body; a flow path forming part fixed to the tank body before forming the heat insulating part on the tank body to form a leak path of liquefied gas between the tank body and the heat insulating part; and a crack arrester installed in the heat insulating part to form one or more layers in order to prevent cracking or separation of the polymer foam sprayed and laminated on the flow path forming part.

Description

Insulation structure of a liquefied gas storage tank and a method of forming an insulation structure of the liquefied gas storage tank

The present invention relates to a thermal insulation structure of a liquefied gas storage tank for storing liquefied gas, and more particularly, to a thermal insulation structure of a liquefied gas storage tank formed by spraying and laminating a polymeric foam on an outer wall of the tank and forming the thermal insulation structure it's about how

Recently, as environmental pollution regulation standards for ships have been strengthened, interest in eco-friendly and high-efficiency liquefied gas fuels such as liquefied natural gas (LNG) or liquefied petroleum gas (LPG) This is increasing.

Liquefied natural gas is liquefied by cooling methane obtained by refining natural gas collected from a gas field. .

In particular, liquefied natural gas (hereinafter referred to as 'LNG') is obtained by cooling natural gas to a cryogenic temperature (about -163 ℃). It is very suitable for long-distance transport.

Liquefied gas is transported in a gaseous state through a gas pipeline on land or sea, or stored in a liquid state in a transport ship and transported to a remote consumer.

A liquefied gas carrier for loading and unloading liquefied gas to a destination on land by navigating the sea with LNG, etc. A liquefied gas storage tank (commonly referred to as a 'cargo hold') that can withstand the cryogenic temperature of LNG is provided in an LNG RV (regasification vessel).

In addition, LNG FPSO (Floating, Production, Storage and Offloading), which is used to liquefy and store the produced natural gas directly at sea, and to transfer stored LNG to an LNG carrier when necessary, and to store LNG unloaded from an LNG carrier at sea Liquefied gas storage tanks installed in LNG carriers or LNG RVs are also included in offshore structures such as LNG FSRUs (Floating Storage and Regasification Units) that vaporize LNG as needed and supply it to onshore consumers.

Such a liquefied gas storage tank can be classified into a membrane type and an independent type depending on whether the load of the cargo acts directly on the insulation material.

Membrane-type storage tanks are divided into No 96 type and Mark III type, and independent storage tanks are divided into Type A, Type B, and Type C according to the regulations of the International Maritime Organization (IMO). The storage tank includes a spherical type MOSS tank and a prismatic type SPB tank.

The membranous storage tank is directly connected to the structure of the hull and is not separated from the hull, and has a structure in which a primary barrier and a secondary barrier are stacked on the inner wall of the hull. As the membranous tank is directly connected to the hull, the load of the liquefied gas stored inside is transferred to the hull without the storage tank supporting it.

On the other hand, the independent storage tank is manufactured to be mounted on the hull after being separated from the structure of the hull, and has a structure in which an insulating material is surrounded by the outer wall of the storage tank. The independent storage tank is separated from the hull and supported by a support structure provided inside the hull, so that the load of the liquefied gas stored therein acts directly on the storage tank.

Independent storage tanks, unlike membranous storage tanks, do not have a complicated barrier structure, and are relatively advantageous in terms of structural stability against sloshing compared to membrane-type storage tanks. It has the advantage of being easy to maintain.

Republic of Korea Patent Publication No. 10-1034472

Independent storage tank according to the prior art, aluminum alloy (aluminum alloy), SUS (Steel Use Stainless) or, 9% nickel alloy (9% Nickel steel) on the outer wall of the tank made of a strong alloy such as polyurethane foam (PUF) ; The insulating layer is formed using a polymeric foam such as Polyurethane Foam, and it is placed on a separate support structure provided under the hull.

In the prior art, the heat insulation layer may be applied by spraying and stacking a polymer foam on the outer wall of the tank for a predetermined time using a device such as a spray gun, and the type of polymer foam or the insulation performance of the polymer foam Its thickness is determined by

On the other hand, these independent storage tanks, when leakage of liquefied gas occurs on the outer wall of the tank, it can cause fatal damage to the hull vulnerable to cryogenic temperature, so that the leaked liquefied gas is prevented from contacting the hull and the leaked liquefied gas can be safely collected or , has a partial secondary barrier structure for recovery.

In other words, a drip tray is installed in the lower part of the storage tank to minimize the direct impact on the hull in case of leakage of liquefied gas, and IGC code; International code for the construction and equipment of ships carrying The size of the drip tray is designed by estimating the amount of leakage over 15 days according to the liquefied gases in bulk).

Here, a leak path through which the leaked liquefied gas can flow to the drip tray by gravity must be provided between the outer wall of the tank and the heat insulating layer. It is difficult to form a leakage path to prepare for leakage of liquefied gas as the insulation layer and the insulation layer are completely adhered.

The present invention forms an insulating layer by spraying and laminating polymer foam on the outer wall of the tank for insulation of the liquefied gas accommodated in the storage tank, but liquefaction capable of forming a leak path for the movement of the leaked liquefied gas between the outer wall of the tank and the heat insulation layer An object of the present invention is to provide a thermal insulation structure of a gas storage tank and a method for forming the thermal insulation structure thereof.

According to one aspect of the present invention, there is provided an insulating structure of a liquefied gas storage tank for insulating liquefied gas stored inside a tank body, comprising: an insulating portion formed by spraying and laminating a polymer foam a plurality of times on the outer surface of the tank body; a flow path forming part fixed to the tank body before forming the heat insulating part on the tank body to form a leak path of liquefied gas between the tank body and the heat insulating part; And a liquefied gas storage tank comprising a crack arrester installed in the heat insulating part to prevent cracking or separation of the polymer foam sprayed and laminated on the flow path forming part to form one or more layers?? An insulating structure may be provided.

The flow path forming unit may include a plurality of heat insulating blocks having a grid-shaped empty space on one surface.

In addition, the heat insulating block, the body portion having a predetermined thickness; And it protrudes from the body portion toward the outer surface of the tank body, it may include a raised portion spaced apart from each other on the tank body.

In addition, the raised portion may have a rectangular, polygonal, or circular cross-sectional shape.

In addition, it may further include a fixing unit for fixing each of the plurality of insulating blocks.

In addition, the fixing part, the stud member fixedly installed on the tank body; and a coupling part coupled to the stud member.

In addition, the fastening portion, a nut screwed to the stud member; and a washer fitted between the stud member and the nut.

In addition, the fixing part may further include a plywood interposed between the stud member and the coupling part.

In addition, it may further include a rotation preventing member installed between the plurality of heat insulating blocks to prevent rotation of each of the plurality of heat insulating blocks.

In addition, the crack preventing unit, a first crack preventing layer installed within 100 mm from the outer surface of the tank body; and a second anti-crack layer installed at a position higher than that of the first crack-preventing layer in the heat insulating part.

According to another aspect of the present invention, there is provided a method for forming a thermal insulation structure of a liquefied gas storage tank for insulating liquefied gas stored in a tank body, and includes a flow path forming unit including a plurality of insulating blocks having a grid-shaped empty space on one surface. fixing to the tank body through a government; And there may be provided a method of forming a thermal insulation structure of a liquefied gas storage tank comprising the step of forming a thermal insulation portion by spraying and laminating a polymer foam on the flow passage forming portion.

In the forming of the heat insulating part, it may include installing a crack preventing part for forming one or more layers in the heat insulating part.

According to the present invention, the flow path forming part is fixed to the tank body before the polymer foam is sprayed on the outer surface of the tank body, so that when the liquefied gas leaks, the liquefied gas leaked through the empty space formed in the insulating block is provided at the lower part of the tank body. It can provide a leak path to the tray.

In addition, since each of the plurality of insulating blocks is not directly attached to the outer surface of the tank body, it can have the effect of flexibly coping with the stress generated due to the difference in the coefficient of thermal expansion between the tank body and the insulating unit in a cryogenic environment.

In addition, it is possible to prevent in advance that the cracks in the polymer foam due to the leakage of liquefied gas through the crack preventing portion forming one or more layers in the heat insulating portion or from developing in advance.

1 is a view showing a part of a cross-section of a heat insulating structure of a liquefied gas storage tank according to a first embodiment of the present invention.
2 is an enlarged view showing the main configuration of the insulating structure of the liquefied gas storage tank according to the first embodiment of the present invention.
3 is a view for explaining a method of forming a thermal insulation structure of a liquefied gas storage tank according to a first embodiment of the present invention.
4 is a view showing a plan view of the insulating structure of the liquefied gas storage tank shown in FIG. 3 .
5 is a view showing a part of a cross-section of the insulating structure of the liquefied gas storage tank according to the second embodiment of the present invention.
6 is a view showing a plan view of the insulating block shown in FIG.
7 is a view showing a portion of a cross section excluding a heat insulating part in the heat insulating structure according to the second embodiment of the present invention.

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

First of all, it should be noted that in adding reference numerals to the components of each drawing, the same components are given the same reference numerals as much 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 configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described, but the technical spirit of the present invention is not limited thereto and may be variously implemented by those skilled in the art without being limited thereto.

In describing the present invention, the liquefied gas is generally liquefied such as LNG (Liquified Natural Gas) at cryogenic temperature (about -163° C.), LPG (Liquefied Petroleum Gas) or Liquefied Ethylene Gas, etc. It may include all gas fuels stored as , and liquefied gas may mean including not only liquefied gas in a liquid state but also vaporized liquefied gas.

The present invention relates to a thermal insulation structure of a liquefied gas storage tank for insulating liquefied gas stored inside a tank body, and can be applied to an independent liquefied gas storage tank manufactured separately from the hull structure and mounted on the hull, Preferably, it can be applied to a self-supporting prismatic-shape IMO Type B (SPB) type independent liquefied gas storage tank.

Here, the tank body may be made of an alloy resistant to low temperatures, such as aluminum alloy, Steel Use Stainless (SUS), or 9% nickel alloy (9% Nickel steel). It can be made of high-manganese steel (High-Mn steel) material that can withstand extremely low temperatures due to excellent brittleness resistance at low temperatures.

In addition, the insulation structure of the liquefied gas storage tank according to the present invention can be applied to any of the offshore structures used while floating in the sea where the flow occurs, and a liquefied gas carrier or LNG RV (LNG Regasification) that transports LNG or LPG. Vessel), as well as offshore plants such as LNG FPSO (Floating, Production, Storage and Offloading) or LNG FSRU (Floating Storage and Regasification Unit) can be all applied.

1 is a view showing a part of a cross-section of a thermal insulation structure of a liquefied gas storage tank according to a first embodiment of the present invention, and FIG. 2 is a main configuration of the thermal insulation structure of a liquefied gas storage tank according to a first embodiment of the present invention. It is a view showing an enlarged view, and FIGS. 3 to 4 are views for explaining a method of forming a thermal insulation structure of a liquefied gas storage tank according to a first embodiment of the present invention.

First, referring to FIG. 1 , the heat insulating structure 100 of the liquefied gas storage tank according to the first embodiment of the present invention may include a flow path forming unit 110 and a heat insulating unit 130 .

The flow path forming unit 110 may include a plurality of heat insulating blocks 111 having a polygonal shape such as a spherical shape or a pentagonal to hexagonal shape, and the plurality of heat insulating blocks 111 are polymer foam on the outer surface of the tank body 10 . It may be temporarily fixed to the tank body 10 through an adhesive or the like before spraying.

Here, each of the plurality of heat insulating blocks 111 may be made of the same material as the heat insulating part 130 to be described later, and may preferably be made of a polyurethane foam material.

The heat insulating structure 100 of this embodiment is, by fixing the flow path forming part 110 to the tank body 10 before spraying the polymer foam on the outer surface of the tank body 10, when leakage of liquefied gas occurs, the flow path forming part ( In addition to preventing the liquefied gas leaked by 110 from penetrating into the heat insulating part 130 , the liquefied gas leaked through the gap G between the plurality of heat insulating blocks 111 is the lower part of the tank body 10 . It is possible to provide a leak path that can flow to a drip tray (not shown) provided in the .

In addition, since each of the plurality of insulation blocks 111 has a spherical or polygonal shape, a key or a support structure (not shown) for supporting the corner portion of the tank body 10 or the tank body 10 is installed, It can have the effect that it can be easily installed even in an area having a complex shape.

In this embodiment, when the size of the gap (G) between the plurality of insulation blocks 111 increases, it may affect the insulation performance of the liquefied gas stored inside the tank body 10, so the plurality of insulation blocks 111 ) may be provided with different sizes to reduce the gap (G) therebetween.

The flow path forming part 110 of this embodiment may be formed over the entire outer surface of the tank body 10 , but may be installed only on the outer surface of the tank body 10 with a high possibility of leakage of liquefied gas.

In this embodiment, the high probability of leakage of liquefied gas may include an outer plate welding portion of the tank body 10 , a welding seam line (such as a welding seam line), and the like, and a longitudinal stiffener in the tank body 10 . ), such as internal reinforcement (not shown) may be meant to include up to the back of the welding installation site.

In this area, stress is concentrated during thermal deformation of the tank body 10 due to cryogenic liquefied gas, and liquefied gas leakage due to breakage may occur, thereby causing cracking or damage of the insulation unit 130. .

In the thermal insulation structure 100 of this embodiment, the flow path forming part 110 is installed in a part where the possibility of leakage of liquefied gas is high in the tank body 10 , so that the leaked liquefied gas remains on the outer surface of the tank body 10 . It is possible to minimize the time and to prevent in advance the occurrence of overpressure due to vaporization of the leaked liquefied gas between the tank body 10 and the heat insulating part 130 .

In addition, even if the plurality of heat insulating blocks 111 are fixed by the heat insulating part 130 , horizontal movement with respect to the tank body 10 is allowed to some extent, so that when thermal deformation of the tank body 10 occurs, the tank body 10 . By performing the same behavior as described above, damage to the thermal insulation unit 130 due to a difference between the thermal expansion coefficients of the tank body 10 and the thermal insulation unit 130 may be minimized.

On the other hand, the operation of attaching each of the plurality of insulation blocks 111 having a spherical or polygonal shape to the tank body 10 may be somewhat cumbersome, and only some of the plurality of insulation blocks 111 through an adhesive or the like are used in the tank body ( 10), it may not be easy to form the heat insulating part 130 due to the movement of the heat insulating blocks 111 in the process of spraying the polymer foam.

The flow path forming unit 110 of this embodiment may further include one or more movement limiting means 113 for restricting movement of the plurality of heat insulating blocks 111 on the outer surface of the tank body 10 .

The movement limiting means 113 is made of a glass fiber material and provided to surround at least a portion of the plurality of heat insulating blocks 111. A mesh type fiber galss mesh 113a and a plurality of heat insulating blocks 111 are provided. It may include at least one of a fiber glass line (113b) which penetrates at least a portion of the block (111) and interconnects the plurality of heat insulating blocks (111).

2 is an enlarged view showing the flow path forming part 110 of the heat insulating structure 100 of the liquefied gas storage tank according to the first embodiment of the present invention. It is shown that it is provided to surround the plurality of heat insulating blocks 111, (b) of FIG. 2 shows that the glass fiber string 113b penetrates the plurality of heat insulating blocks 111 and connects the plurality of heat insulating blocks 111 with each other. A tight connection is shown.

That is, the plurality of heat insulating blocks 111 may be fixed to the outer surface of the tank body 10 in a state in which they are in close contact with each other by the plurality of glass fiber networks 113a, and only some of the plurality of heat insulating blocks 111 are glass fiber meshes. (113a) may be wrapped in close contact with each other and then fixed to the outer surface of the tank body (10).

In addition, some of the plurality of insulation blocks 111 are installed on the outer surface of the tank body 10 in a state of being wrapped in the glass fiber network 113a, and the other part of the plurality of insulation blocks 111 is a glass fiber string 113b. ) may be installed on the outer surface of the tank body 10 in a penetrating state.

Here, the glass fiber string (113b) may be provided in the form of a single thread, or may be provided in the form of a rope by twisting a bundle of threads.

The heat insulating structure 100 of the liquefied gas storage tank according to the first embodiment of the present invention is a plurality of heat insulating blocks ( 111) The hassle of installing each on the outer surface of the tank body 10 can be reduced, and it is possible to attach some of the plurality of heat insulating blocks 111 to the tank body 10 at once, thereby providing convenience to the operation. .

The heat insulating part 130 is formed by spraying and stacking a polymer foam such as polyurethane foam (PUF) a plurality of times from the outside of the tank body 10 using a device such as a spray gun, the tank body ( 10) The thickness can be changed according to the size and type.

In this embodiment, the heat insulating portion 130 may be formed of one or more layers having a thickness that can ensure sufficient heat insulation performance in consideration of the type or density of the polymer foam laminated and sprayed on the outer surface of the tank body 10 .

As shown in FIG. 1 , the heat insulating unit 130 may be formed of two or more layers, and includes a flow path forming unit 110 temporarily fixed to the outer surface of the tank body 10 from the outside of the tank body 10 . It may include a primary insulating layer 131 formed by spraying a polymer foam to include, and a secondary insulating layer 133 formed by spraying a polymer foam on the primary insulating layer 131 .

The primary insulating layer 131 and the secondary insulating layer 133 of this embodiment may be formed by spray-stacking polymer foam having the same density, or may be formed of the same material but have different densities.

Here, when the primary insulating layer 131 and the secondary insulating layer 133 are provided with different densities from each other, it may be preferable to form a thin thickness as the density increases.

Meanwhile, the heat insulating structure 100 of the liquefied gas storage tank according to an embodiment of the present invention may further include a fixing part 150 for fixing the flow path forming part 110 and the heat insulating part 130 .

The fixing part 150 may include a stud 151 fixedly installed on the tank body 10 and a fastening member 153 fastened to the stud 151 , and the fastening member 153 forms a flow path. It may be preferable to be provided to fix the part 110 and the primary heat insulating layer 131 .

1 and 3, although it is shown that the fastening member 153 of this embodiment is positioned on the primary heat insulating layer 131, the present invention is not limited thereto, and the fastening member 153 of this embodiment is It may be located in the primary heat insulating layer 131 .

The stud 151 may be made of a metal or a composite material of the same material as the tank body 10 , and the fastening member 153 may be provided with either a washer or a nut.

Here, when a washer is used as the fastening member 153, the inner diameter of the washer corresponds to the diameter of the stud, and the inner circumferential surface of the washer has a screw groove corresponding to the thread (not shown) formed on the outer circumferential surface of the stud 151. It may be desirable to form

Hereinafter, with reference to FIGS. 3 to 4, a method for forming a thermal insulation structure of a liquefied gas storage tank according to a first embodiment of the present invention will be briefly described.

In the method for forming a thermal insulation structure of a liquefied gas storage tank according to the first embodiment of the present invention, the flow path forming unit 110 including a plurality of thermal insulation blocks 111 having a spherical or polygonal shape is installed in the tank body 10 . It may include a step of temporarily fixing and spraying and stacking a polymer foam on the flow path forming unit 110 to form the heat insulating unit 130 , and the flow path forming unit 110 may include a plurality of It is possible to provide a leakage path of the liquefied gas leaked through the gap (G) between the insulating blocks (111).

In other words, after installing a plurality of heat insulating blocks 111 on the outer surface of the tank body 10 (refer to (a) of FIG. 3 ), the tank body 10 includes a plurality of heat insulating blocks 111 from the outside. The polymer foam is spray laminated to form the primary heat insulating layer 131 (see Fig. 3 (b)), and the polymer foam is spray laminated again on the first heat insulating layer 131 to form the secondary heat insulating layer 133 (Fig. 3 (c)) can be done.

Here, the plurality of insulating blocks 111 may be installed only on the outer surface of the tank body 10 with a high possibility of leakage of the liquefied gas.

In addition, after the polymer foam is sprayed on the plurality of heat insulating blocks 111 to form the first heat insulating layer 131 , the fastening member 153 is coupled to the studs 151 fixed to the tank body 10 to The plurality of heat insulating blocks 111 and the first heat insulating layer 131 are fixed, and the second heat insulating layer 133 can be formed by spraying and laminating a polymer foam on the first heat insulating layer 131 and the fixing part 150 .

In this embodiment, by fixing the flow path forming part to the tank body before spraying the polymer foam on the outer surface of the tank body, when leakage of liquefied gas occurs, the leaked liquefied gas by the flow path forming part is prevented from penetrating into the heat insulating part, and , it is possible to provide a leak path through which the liquefied gas leaked through the gap between the plurality of insulating blocks can flow to the drip tray provided at the lower part of the tank body.

In addition, since each of the plurality of insulating blocks has a spherical or polygonal shape, a support structure for supporting the corner portion of the tank body or the tank body is installed so that it can be easily installed even in an area having a complex shape.

In addition, the flow path forming part is installed in a part where the leakage of liquefied gas is high in the tank body, thereby minimizing the time that the leaked liquefied gas remains on the outer surface of the tank body and vaporizing the leaked liquefied gas between the tank body and the heat insulating part. It is possible to prevent in advance the occurrence of overpressure caused by this.

In addition, even if the plurality of insulating blocks are fixed by the insulating part, horizontal movement with respect to the tank body is allowed to some extent, so when thermal deformation of the tank body occurs, it behaves like the tank body, resulting in a difference in thermal expansion coefficient between the tank body and the insulating part Damage to the insulation can be minimized.

In addition, by closely connecting at least some of the plurality of heat insulating blocks to each other through the movement limiting means, the hassle of installing each of the plurality of heat insulating blocks on the outer surface of the tank body can be reduced, and some of the plurality of heat insulating blocks are attached to the tank body. Since it can be attached at once, convenience can be provided for work.

5 is a view showing a part of a cross-section of a heat insulating structure of a liquefied gas storage tank according to a second embodiment of the present invention, FIG. 6 is a view showing a plan view of the heat insulating block shown in FIG. 5, FIG. 7 is this view It is a view showing a part of the cross section excluding the heat insulating part in the heat insulating structure according to the second embodiment of the present invention.

5 to 7, the insulating structure 200 of the liquefied gas storage tank according to the second embodiment of the present invention, similar to the first embodiment, a flow path for providing a leakage path of the leaked liquefied gas It may include a heat insulating part 230 formed by spraying and stacking the polymer foam on the forming part 210 and the channel forming part 210, and the channel forming part 210 is an empty space (S) in the form of a grid on one surface. It may include a plurality of heat insulating blocks 211 having a.

The insulating block 211 in this embodiment, similar to the first embodiment, may be made of a polyurethane foam (Polyurethane foam) material, and each of the plurality of insulating blocks 211 is formed by a fixing part 250 . It may be fixed to the outer surface of the tank body (10).

Specifically, the insulating block 211 of this embodiment is positioned in parallel with the outer surface of the tank body 10 and has a body portion 211a having a predetermined thickness, and from the body portion 211a toward the outer surface of the tank body 10 Doedoe raised so as to include a raised portion (211b) spaced apart from each other on the tank body (10).

Referring to FIG. 6 , the raised portion 211b has a rectangular cross-section, but the present invention is not limited thereto. may have, and extend toward the outer surface of the tank body 10 to have a cylindrical or polygonal column shape.

In addition, the raised portion 211b of this embodiment is formed extending from the body portion 211a toward the outer surface of the tank body 10, and may be provided with different widths (or diameters) in the longitudinal direction thereof.

That is, the raised portion 211b may be formed to have a smaller width or diameter as it approaches the outer surface of the tank body 10 from the body portion 211a, and one surface of the insulating block 211 by the raised portion 211b. The empty space (S) formed in the body portion (211a) is formed to gradually widen as it approaches the outer surface of the tank body (10), so that the leaked liquefied gas through the empty space moves smoothly can do.

The insulating structure 200 of the liquefied gas storage tank according to the second embodiment of the present invention may further include a fixing unit 250 for fixing each of the plurality of insulating blocks 211 .

The fixing part 250 may include a stud member 251 fixedly installed on the tank body 10 and a coupling part 253 coupled to the stud member 251 as shown in FIG. 7 .

The stud member 251, similarly to the stud 151 of the first embodiment, may be made of the same material as the tank body 10, such as a metal or a composite material.

The coupling portion 253 is for fixing each of the plurality of heat insulating blocks 211, a nut 253a screwed to the stud member 251, and the stud member 251 and the nut 253a. A washer 253b may be included.

The fixing part 250 of this embodiment is interposed between the stud member 251 and the coupling part 253 in order to more firmly support the insulating block 211 according to the position of the tank body 10. Plywood. (255) (refer to (b) of FIG. 7) may be further included.

Here, each of the plurality of insulating blocks 211 may be pre-formed with a hole (unsigned) having a size corresponding to or larger than the diameter of the stud 151 before being installed on the outer surface of the tank body 10 . .

The heat insulating structure 200 of this embodiment is, by fixing the flow path forming part 210 to the tank body 10 before spraying the polymer foam on the outer surface of the tank body 10, when leakage of liquefied gas occurs, the flow path forming part ( In addition to preventing the liquefied gas leaked by the 210 from penetrating into the insulating unit 230 , the liquefied gas leaked through the empty space S in the insulating block 211 is provided at the bottom of the tank body 10 . It can provide a leak path to the drip tray.

In addition, since each of the plurality of heat insulating blocks 211 is not directly attached to the outer surface of the tank body 10, the stress generated due to the difference in the thermal expansion coefficient between the tank body 10 and the heat insulating unit 130 in a cryogenic environment is flexible. It can have a beneficial effect that can be dealt with.

On the other hand, the plurality of insulating blocks 211 of this embodiment may be spaced apart from each other on the outer surface of the tank body 10 according to the position of the stud member 251 fixed to the outer surface of the tank body 10, polymer foam is sprayed. In the process, each of the plurality of heat insulating blocks 211 may be rotated around the stud member 251 , and thus the work of forming the heat insulating unit 230 may not be easy.

The flow path forming part 210 of this embodiment is a rotation preventing member (not shown) installed between the plurality of heat insulating blocks 211 in order to prevent rotation of the heat insulating block 211 due to being spaced apart between the plurality of heat insulating blocks 211 . ) may be further included.

Here, the anti-rotation member may have the same material as the heat insulating block 211, and it may be preferable to be installed between the plurality of heat insulating blocks 211 in an interference fit manner.

In addition, the flow path forming part 210 of this embodiment, similar to the first embodiment, may be formed over the entire area of the outer surface of the tank body 10, the possibility of leakage of liquefied gas from the outer surface of the tank body 10 It may be installed only in this high area.

Insulation portion 230, similarly to the first embodiment, similarly, polymer foam such as polyurethane foam (PUF) from the outside of the tank body 10 may be formed by spraying and stacking a plurality of times, sufficient thermal insulation performance It may have a thickness that can be ensured and may consist of one or more layers.

The heat insulating part 230 of this embodiment, as shown in FIG. 5 , a first heat insulating layer 231 , a second heat insulating layer 233 , and a third heat insulating layer 233 in a direction away from the outer surface of the tank body 10 . These are sequentially installed, and may consist of three layers.

The first to third heat-insulating layers 231, 233, 235 may be formed by spray-stacking polymer foam having the same density, and at least one of the first to third heat-insulating layers 231, 233, 235 is made of the same material. However, it may have a different density than the rest.

In addition, when the first to third heat insulating layers 231 , 233 , and 235 have different densities, it may be preferable to form a thinner thickness as the density increases.

On the other hand, when a leak of liquefied gas occurs in the tank body 10 even if a leak path is formed through the empty space S within the plurality of heat insulating blocks 211 , the space between the tank body 10 and the heat insulating part 230 is Due to the increase in pressure, the polymer foam constituting the heat insulating part 230 may contract or relax, and cracks may occur.

The insulating structure 200 of this embodiment is to maintain the rigidity of the polymer foam even if pressure is generated between the tank body 10 and the heat insulating part 230 due to the leaked liquefied gas or vaporization of the leaked liquefied gas. To this end, it may further include a crack preventing unit 270 .

In this embodiment, the crack preventing unit 270 may form one or more layers in the insulating unit 230 , and the insulating unit 230 may be divided into a plurality of layers by the crack preventing unit 270 . .

As an example, a plurality of heat insulating blocks 211 are fixed to the outer surface of the tank body 10 through a fixing part 250 before the polymer foam is sprayed on the outer surface of the tank body 10 , and a plurality of heat insulating blocks 211 are fixed to the outer surface of the tank body 10 . ), the polymer foam is spray-stacked on it, and then the crack prevention part 270 is installed, and the polymer foam is spray laminated again on the crack prevention part 270 to form the heat insulating part 230 .

In this embodiment, the crack preventing unit 270 may be made of a material such as metal, glass fiber, or a composite material, and a plate or a plate having a mesh shape such as a chain or net, or a lattice structure. It can be provided in the form of a metal sheet, and can serve as a crack arrester to prevent cracks in the polymer foam from occurring or from developing when the pressure rises due to leakage of liquefied gas.

The crack prevention part 270 of this embodiment, as shown in FIG. 5, is installed to be spaced apart from the first crack prevention layer 271 installed adjacent to the outer surface of the tank body 10, and the first crack prevention layer 271 A second crack prevention layer 273 may be included.

That is, the heat insulating part 230 of this embodiment, as shown in FIG. 5, in a direction away from the outer surface of the tank body 10, the first heat insulating layer 231, the second heat insulating layer 233, and the third heat insulating layer ( 233 ) may be sequentially installed, and a first crack prevention layer 271 is installed between the first heat insulating layer 231 and the second heat insulating layer 233 , and between the second heat insulating layer 233 and the third heat insulating layer 235 . The second crack prevention layer 273 may be installed.

In this embodiment, when the heat insulating part 230 has a height (or thickness) of about 300 mm, it may be preferable that the first crack prevention layer 271 be installed within 100 mm from the outer surface of the tank body 10 . have.

In other words, as the heat insulating part 230 approaches the outer surface of the tank body 10 , the temperature load by the liquefied gas accommodated in the tank body 10 becomes larger, and the further away from the tank body 10 , the relative Therefore, it can be less affected by the temperature load.

Therefore, the heat insulating part 230 of this embodiment has a plurality of layers, and the first crack prevention layer 271 is installed at a position (within 100 mm in height) where a relatively large temperature load acts, and the effect of the temperature load is less The height of the heat insulating layer was increased at the receiving position, and by additionally installing the second crack preventing layer 273 at a position higher than the first crack preventing layer 271 from the tank body 10, cracking occurred in the insulating part 230 It may have an optimized structure to prevent it.

In addition, in the heat insulating structure 200 of this embodiment, the plurality of heat insulating blocks 211 may have a height of less than 100 mm, and although not shown in the drawings, the first crack prevention layer 271 of this embodiment is the heat insulating block 211 . It may be located directly on the upper surface of the insulating block 211 according to the height of the.

That is, in a state in which the plurality of heat insulating blocks 211 are fixed to the outer surface of the tank body 10 , a first crack prevention layer 271 is installed on the upper surface of the heat insulating block 211 , and the first crack prevention layer 271 is on the The thermal insulation part 230 may be formed by spray-stacking the polymer foam.

In this embodiment, when the first crack prevention layer 271 is located directly on the upper surface of the heat insulating block 211, more stable fixing than fixing on the polymer foam may be possible.

Meanwhile, in the heat insulating structure 200 of this embodiment, a protection coating layer 290 applied on the heat insulating part 230 to improve the watertightness of the heat insulating part 230 and prevent damage to the heat insulating part 230 . ) may be further included.

Hereinafter, a method for forming a thermal insulation structure of a liquefied gas storage tank according to a second embodiment of the present invention will be briefly described.

In the method for forming a thermal insulation structure of a liquefied gas storage tank according to a second embodiment of the present invention, a flow path forming unit 210 including a plurality of thermal insulation blocks 211 having a grid-shaped empty space (S) on one surface of the tank is formed. It may include fixing to the body 10 and forming the heat insulating part 230 by spraying and laminating a polymer foam on the flow path forming part 210 .

In the step of fixing the flow path forming part 210 to the tank body 10 , each of the plurality of heat insulating blocks 211 may be fixed to the tank body 10 through the fixing part 250 .

In addition, in the step of forming the heat insulating part 230 , in the process of spraying the polymer foam from the outside of the tank body 10 , the crack preventing part 270 in the heat insulating part 230 may be installed, and the heat insulating part 230 . may be divided into a plurality of layers by the crack prevention unit 270 .

In this embodiment, by fixing the flow path forming part to the tank body before spraying the polymer foam on the outer surface of the tank body, when the liquefied gas leaks, the liquefied gas leaked through the empty space formed in the insulating block is located at the lower part of the tank body. It is possible to provide a leak path that can flow to the provided drip tray.

In addition, since each of the plurality of insulating blocks is not directly attached to the outer surface of the tank body, it can have the effect of flexibly coping with the stress generated due to the difference in the coefficient of thermal expansion between the tank body and the insulating unit in a cryogenic environment.

In addition, it is possible to prevent in advance that the cracks in the polymer foam due to the leakage of liquefied gas through the crack preventing portion forming one or more layers in the heat insulating portion or from developing in advance.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains may make various modifications, changes and substitutions within the scope without departing from the essential characteristics of the present invention. will be.

The embodiments disclosed in the present invention and the accompanying drawings are for explanation rather than limiting the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments and the accompanying drawings.

In addition, the protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

10: tank body
200: insulation structure
210: flow path forming part
211: insulation block
213: rotation preventing member
230: insulation
231: first heat insulating layer
233: second heat insulating layer
235: third thermal insulation layer
250: fixed part
251: stud member
253: coupling part
255: plywood
270: crack prevention unit
271: first crack prevention layer
273: second crack prevention layer
290: protective coating layer
S: empty space

Claims (9)

As an insulating structure of a liquefied gas storage tank for insulating the liquefied gas stored inside the tank body,
a heat insulating portion formed by spraying and laminating a polymer foam a plurality of times on the outer surface of the tank body;
a flow path forming part fixed to the tank body before forming the heat insulating part on the tank body to form a leakage path of liquefied gas between the tank body and the heat insulating part; and
In order to prevent cracking or separation of the polymer foam sprayed and laminated on the flow path forming part, it includes a crack arrester installed in the heat insulating part to form one or more layers,
The flow path forming part is an insulating structure of a liquefied gas storage tank including a plurality of insulating blocks having an empty space in the form of a grid on one surface. The method of claim 1,
The insulating block is
a body portion having a predetermined thickness; and
Insulation structure of a liquefied gas storage tank including raised portions that are raised from the body portion toward the outer surface of the tank body, and are spaced apart from each other on the tank body. 3. The method of claim 2,
The raised portion is an insulating structure of a liquefied gas storage tank having a rectangular, polygonal, or circular cross-sectional shape. The method of claim 1,
Further comprising a fixing unit for fixing each of the plurality of insulating blocks,
The fixing part,
a stud member fixedly installed on the tank body; and
Insulation structure of the liquefied gas storage tank including a coupling portion coupled to the stud member. 5. The method of claim 4,
The coupling part,
a nut screwed to the stud member; and
Insulation structure of a liquefied gas storage tank comprising a washer fitted between the stud member and the nut. 5. The method of claim 4,
The fixing part,
Insulation structure of the liquefied gas storage tank further comprising a plywood interposed between the stud member and the coupling portion. 5. The method of claim 4,
The insulation structure of the liquefied gas storage tank further comprising a rotation preventing member installed between the plurality of insulation blocks to prevent rotation of each of the plurality of insulation blocks. The method of claim 1,
The crack prevention unit,
a first crack prevention layer installed within 100 mm from the outer surface of the tank body; and
Insulation structure of a liquefied gas storage tank including a second crack prevention layer installed at a position higher than the first crack prevention layer in the heat insulating part. A method of forming an insulating structure of a liquefied gas storage tank for insulating the liquefied gas stored inside the tank body, the method comprising:
fixing a flow path forming unit including a plurality of heat insulating blocks having a grid-shaped empty space on one surface to the tank body through a fixing unit; and
Comprising the step of forming a heat insulating part by spraying and laminating a polymer foam on the flow path forming part,
In the step of forming the heat insulating part,
A method of forming a thermal insulation structure of a liquefied gas storage tank, comprising the step of installing a crack preventing unit forming one or more layers in the insulating unit.

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