KR102508606B1 - Insulation structure for liquefied gas tank and formation method thereof - Google Patents

Abstract

The present invention relates to a heat insulation structure of a liquefied gas tank and a method for forming the same, and specifically, to an insulation structure formed by spraying on the outer surface of a tank body accommodating liquefied gas therein, wherein the spray on the outer surface of the tank body Insulation structure of a liquefied gas tank formed by laminating a plurality of layers of insulation formed through coating, and at least a portion of the tank body side of the insulation structure includes a plurality of insulation layers having a thickness of 5 mm to 10 mm, and a method of forming the same it's about

Description

Insulation structure for liquefied gas tank and formation method thereof}

The present invention relates to a heat insulation structure of a liquefied gas tank and a method for forming the same.

Liquefied natural gas (LNG), liquefied ethane gas (LEG), and liquefied petroleum gas (LPG) are cooled and liquefied at cryogenic temperatures below the boiling point for transportation and convenience. It is stored and transported by a containment system such as a tank or ship. Such containment systems may be installed on ships, barges, floating platforms, and the like.

The containment system is largely divided into an independent type and a membrane type. The stand-alone type consists of a tank made of aluminum, stainless steel, steel alloy, etc., and an insulator installed on the outer surface of the tank. Membrane type is to construct insulation and hard metal membrane directly on the hull of the ship without manufacturing a separate tank. Insulation, both free-standing and membranous, is widely used for the insulation and protection of tanks or hulls. In this regard, the insulation structure of a liquefied gas storage tank in which a plurality of insulation panels made of polyurethane foam are installed outside the tank body is described in Korean Patent No. 10-166608.

On the other hand, as the insulation structure of the LNG tank, the insulation structure of the spray foam method formed by spraying the outer wall of the tank is gradually expanding.

The spray foam method is a method in which polyurethane foam is laminated by spraying 25 mm to 30 mm at a time, and is a method of spraying and stacking several times up to a required thickness (about 300 mm to 350 mm).

While the spray foam insulation structure has the advantage of good adhesion with adherends, the relatively weak spray foam cannot withstand the shrinkage stress of the tank due to the stress generated by the difference in shrinkage rate from the metal tank at cryogenic temperatures, and the tank surface It has the disadvantage of delamination or cracks in the insulation structure, which deteriorates the performance of the insulation structure.

In order to compensate for these disadvantages, Korean Patent Registration No. 10-1034472 discloses that as an insulation structure for an independent liquefied gas tank, high-density polyurethane spray foam and low-density polyurethane spray foam are applied to the surface of the LNG tank. A sequentially arranged structure has been disclosed.

However, due to the relatively high price of high-density polyurethane spray foam, the economic feasibility is low, and polyurethane spray foam raw materials of different densities must be used, requiring work such as replacing raw materials during work. It has the disadvantage of lighting that the efficiency is lowered.

In addition, since a ship equipped with such a tank operates from the polar region to the equator, the external temperature change is large, and especially in the case of an LNG tank, since there are many tanks installed outside the ship, the influence of the external environment and impact must be considered.

Therefore, the inventors of the present invention reduce the occurrence of defects by the difference in shrinkage with the tank in the insulation structure disposed on the outer surface of the tank used to store and transport liquefied gases such as LNG and LEG, and reduce the external environment and A new insulation structure capable of minimizing the impact from impact was developed and the present invention was completed.

An object of one aspect is to provide a heat insulation structure of a liquefied gas tank and a method of forming the same.

In order to achieve the above purpose,

On one side,

A heat insulation structure formed by spraying on the outer surface of a tank body that accommodates liquefied gas therein,

It is formed by stacking a plurality of layers of insulating material formed through spray coating on the outer surface of the tank body,

At least a portion of the tank body side of the heat insulating structure is provided with a heat insulating structure for a liquefied gas tank, including a plurality of heat insulating layers having a thickness of 5 mm to 10 mm.

The insulation structure is

A low-temperature heat insulating part formed by laminating a heat insulating material layer having a thickness of 5 mm to 10 mm; and

Including; one or more high-temperature insulation parts formed on the low-temperature insulation part,

The high-temperature insulator is formed by stacking an insulator layer thicker than the insulator layer of the low-temperature insulator.

The thickness of at least a portion of the tank body side of the insulating structure may be preferably 45 mm to 55 mm.

The high-temperature insulation part may have a thickness of 300 mm to 500 mm.

The high-temperature insulator may be formed by stacking an insulator layer having a thickness of 15 mm to 40 mm.

The heat insulating material layer includes a skin layer formed on a surface.

The low-temperature insulator and the high-temperature insulator may be made of an insulator having the same density, and the insulator may preferably be polyurethane foam.

The insulation structure may further include a reinforcement layer disposed between the low-temperature insulation part and the high-temperature insulation part or on the high-temperature insulation part and including a crack arrester.

The heat insulating structure may further include a primer adhesive layer disposed between the outer surface of the tank and the low temperature heat insulating part.

The heat insulating structure may further include a coating layer disposed on the high-temperature heat insulating part.

On the other side,

As a method of forming a heat insulation structure of the liquefied gas tank,

Forming a heat insulating structure by laminating a heat insulating material layer a plurality of times through spray coating on the outer surface of the tank body; includes,

At least a portion of the tank body side of the heat insulating structure includes a plurality of heat insulating layers having a thickness of 5 mm to 10 mm, a method for forming a heat insulating structure of a liquefied gas tank is provided.

The method of forming the insulation structure

Forming a low-temperature heat insulating part by laminating a heat insulating material layer having a thickness of 5 mm to 10 mm; and

Forming one or more high-temperature insulation parts on the low-temperature insulation part; includes,

The high-temperature heat insulating part is formed by laminating a heat insulating material layer thicker than the heat insulating material layer of the low-temperature heat insulating part.

The heat insulating material layer includes a skin layer formed on a surface.

On the other side,

As a method of manufacturing the heat insulation structure of the liquefied gas tank,

Forming a heat insulating structure by laminating a heat insulating material layer a plurality of times through spray coating on the outer surface of the tank body; includes,

At least a portion of the tank body side of the insulation structure includes a plurality of insulation layers having a thickness of 5 mm to 10 mm, a method for manufacturing a liquefied gas tank is provided.

The insulation structure of a liquefied gas tank according to one aspect includes an area formed by spraying a thin layer of 5 to 10 mm on the outer surface of a tank body accommodating liquefied gas therein, and at least an insulation material adjacent to the tank body. Since the mechanical strength of the layer is increased, it has a high insulation performance and at the same time has the advantage of significantly reducing the occurrence of cracks due to the stress caused by the difference in shrinkage with the tank.

In addition, since a single material and an insulating material of the same density can be used, the economic efficiency of using raw materials can be increased and the cost of waste disposal can be reduced compared to the case of using several types of insulating materials.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

1 is a view schematically showing a thermal insulation structure of a liquefied gas tank according to an embodiment,
2 is a view schematically showing a heat insulating material layer of a heat insulating structure of a liquefied gas tank according to an embodiment,
3 is a view schematically showing a thermal insulation structure of a liquefied gas tank according to another embodiment,
4 is a view schematically showing a thermal insulation structure of a liquefied gas tank according to another embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, it should be understood that the present invention is not limited to the specific embodiments below, and includes all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

Terms used in this specification are only used to describe specific embodiments, and the present invention is not limited thereto.

Throughout the specification and claims, the terms “first” and “second” are used herein for purposes of distinction and are not meant to indicate or predict order or order in any way, and are not meant to represent the various components. Although used to describe, the components are not limited by the terms. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

In addition, when a component is referred to as "connected" or "connected" to another component, it may be directly connected or connected to the other component, but other components may exist in the middle. It should be understood. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

In addition, the terms "include" or "have" are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, and one or more other features or The presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not excluded.

In addition, unless defined otherwise, all terms used in this specification, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this specification, they should not be interpreted in an ideal or excessively formal meaning. don't

On one side,

A heat insulation structure formed by spraying on the outer surface of a tank body that accommodates liquefied gas therein,

It is formed by stacking a plurality of layers of insulating material formed through spray coating on the outer surface of the tank body,

At least a portion of the tank body side of the heat insulating structure is provided with a heat insulating structure for a liquefied gas tank, including a plurality of heat insulating layers having a thickness of 5 mm to 10 mm.

Hereinafter, an insulation structure of a liquefied gas tank according to an embodiment will be described in detail with reference to the drawings.

The heat insulation structure 1 of the liquefied gas tank according to one aspect is a heat insulation structure formed by spraying on the outer surface of a tank body accommodating liquefied gas therein.

The liquefied gas tank may be, for example, an independent liquefied gas tank having a cylindrical pressure vessel or a polygonal box shape, but the shape or type of the tank is not particularly limited.

In addition, the insulation structure may be applied not only to an independent liquefied gas tank on land, but also to any floating offshore structure at sea where flow occurs while an independent liquefied gas tank is installed, in other words, liquefied natural gas (LNG) or liquefied gas LNG FPSO (Floating, Production, Storage and Offloading) or LNG FSRU (Floating Storage and Regasification Unit), as well as ships such as liquefied gas carriers or LNG RVs (LNG Regasification Vessel) that transport ethane gas (LEG), etc. It can be applied to all plants and the like.

When storing LNG in a tank, the temperature of LNG is approximately -163°C, which is very low compared to LPG, which has a temperature of approximately -50°C. need to configure.

In addition, since it can be applied to any of the offshore structures, it is necessary to construct an insulation structure capable of withstanding various climates and shocks.

1 is a view schematically showing a thermal insulation structure of a liquefied gas tank according to an embodiment.

As shown in FIG. 1, the heat insulating structure 1 of the liquefied gas tank according to one side is formed by stacking a plurality of layers of heat insulating material formed through spray coating on the outer surface of the tank body.

The heat insulating material layer 10 means a layer formed by spraying a heat insulating material.

When the insulation structure formed by spraying the tank body accommodating liquefied gas is constructed with a single layer of insulation, there is no resistance to deformation of the tank, so there is a problem in that cracks are easily generated and propagated in the insulation structure.

Since the insulating structure 1 of the liquefied gas tank according to one aspect includes a plurality of insulating material layers stacked on the outer surface of the tank body, the resistance to deformation of the tank is high, thereby reducing the occurrence of cracks in the insulating structure and their propagation. can

The heat insulating material constituting the heat insulating material layer 10 of the heat insulating structure 1 of the liquefied gas tank according to an embodiment may be preferably polyurethane foam (PU foam).

At this time, the polyurethane foam (PU foam) may have a density of 10 kg/m ³ to 100 kg/m ³ , preferably 20 kg/m ³ to 80 kg/m ³ , and more preferably 20 kg/m 3 to 80 kg/m 3 . It may be kg/m ³ to 60 kg/m ³ and more preferably 30 kg/m ³ to 50 kg/m ³ .

If the density of the polyurethane foam is less than 10 kg / m ³ , the strength is not expressed, the shape is not maintained, or the tensile force is lowered, so there is no crack resistance, so even a slight stress may cause problems in that the polyurethane foam is damaged or cracked. And, if it exceeds 100 kg / m ³ , brittleness is strong, it is not able to absorb external force, and cracking occurs, or thermal conductivity is increased, which may cause a problem in that insulation performance is lowered.

Insulation structure 1 of a liquefied gas tank according to one side includes at least a portion of the tank body side, more specifically, at least a portion of the thickness direction of the insulation layer from one end of the tank side is a plurality of insulation layers having a thin thickness of 5 mm to 10 mm. includes dogs.

The insulation structure 1 of the liquefied gas tank according to one aspect increases the mechanical strength of at least a region adjacent to the tank body by laminating a plurality of thin insulation layers having a thickness of 5 mm to 10 mm on at least a portion of the tank body side of the insulation structure. can be further improved.

2 is a view schematically showing a heat insulating material layer 10 of a heat insulating structure of a liquefied gas tank according to an embodiment.

As shown in FIG. 2, the heat insulating material layer 10 includes a skin layer 11 on the surface.

The skin layer 11 may be a layer having a lower porosity that is formed on the surface of the heat insulating material layer 10 during spraying.

For example, the skin layer 11 is a layer naturally formed on the surface when polyurethane foam is sprayed.

The heat insulating material layer 10 may be made of polyurethane foam, and the internal porosity of the heat insulating material layer made of polyurethane foam is 90% to 98%, while the pores of the skin layer 11 of the heat insulating material layer made of polyurethane foam The degree may be 20% or less, more preferably 1 to 20%.

Since at least a part of the tank body side of the heat insulating structure is formed by stacking a thin heat insulating material layer having a thickness of 5 mm to 10 mm, the skin layer 11 may be formed every 5 mm to 10 mm in the thickness direction.

For example, the heat insulating structure 1 forms a heat insulating material layer 10 having a thickness of 5 mm by spraying polyurethane foam on the outer surface of a tank body accommodating liquefied gas, and the heat insulating material layer 10 It may include a region formed by stacking 10. Since skin layers 11 are formed every 5 mm in the thickness direction from the tank body side by the heat insulating material layer 10, the area may include a total of 10 skin layers 11.

In the heat insulating structure 1 according to an embodiment, mechanical strength of at least a region adjacent to the tank body is further improved by forming more skin layers 11 on at least a portion of the tank body side of the heat insulating structure in the same manner as described above. can make it

If the thickness of the heat insulating material layer 10 is less than 5 mm, the thickness is very thin and a problem may occur that it is difficult to uniformly manufacture by the spray method, and when the thickness of the heat insulating material layer 10 exceeds 10 mm, Since the mechanical strength of the low-temperature insulator 100 is insufficient, an effect of preventing cracks from occurring may be insufficient due to a difference in shrinkage from a tank storing liquid gas at a cryogenic temperature.

The single structure 1 may have a thickness of 300 mm to 500 mm, more preferably 300 mm to 400 mm.

The thickness of at least a part of the tank body side of the unitary structure 1 may be 20 mm or more, preferably 20 mm to 100 mm, preferably 30 mm to 60 mm, and more preferably 45 mm to 55 mm. .

If the thickness of the region where the insulating material layer having a thickness of 5 mm to 10 mm is formed is less than 20 mm, the degree of improvement in the mechanical strength of the insulating structure 1 is insufficient, and the difference in shrinkage with the tank for storing liquid gas at cryogenic temperatures Due to this, the effect of preventing cracks may be insufficient, and when the thickness of the area where the thickness of the 5 mm to 10 mm insulation layer is formed exceeds 100 mm, the amount of material required increases and a lot of time is invested in the work, so the construction period This may cause a problem in that the manufacturing efficiency is lowered due to the length.

3 is a view schematically showing a thermal insulation structure of a liquefied gas tank according to another embodiment.

As shown in FIG. 3, the heat insulating structure 1,

A low-temperature heat insulating unit 100 formed by stacking insulating material layers having a thickness of 5 mm to 10 mm; and

One or more high-temperature insulators 200 formed on the low-temperature insulator 100; and the high-temperature insulator 200 may be formed by stacking an insulating material layer thicker than the insulating material layer of the low-temperature insulating part. .

In the insulation structure 1 according to one aspect, a sufficient number of skin layers 11 can be formed by laminating a plurality of thin insulation layers having a thickness of 5 mm to 10 mm on the low-temperature insulation part 100, and through this, the liquefied gas tank and By improving the mechanical strength of the adjacent area, it is possible to significantly reduce cracks caused by stress caused by a difference in shrinkage with the tank.

For example, as shown in FIG. 3, the insulation structure 1 includes a low-temperature insulation unit 100 formed by stacking a first insulation layer having a thin thickness of 5 mm to 10 mm on the outer surface of the tank body, the It may include; a high-temperature insulator 200 formed by laminating a second insulator layer having a thickness of 15 mm to 40 mm on the low-temperature insulator 100.

In this case, the components and densities of the first insulating material layer and the second insulating material layer may be the same.

For example, the first insulating material layer and the second insulating material layer may be made of polyurethane foam having a density of 30 kg/m ³ to 50 kg/m ³ .

The insulation structure of a liquefied gas tank according to an embodiment is formed by forming insulation layers made of insulation materials having the same density in different thicknesses, more preferably in a thickness of 5 mm to 10 mm on at least a portion of the tank body side, at least part of the insulation structure. The mechanical strength of can be further improved.

The heat insulation structure 1 may include one or more, preferably two or more high-temperature insulation parts 200 .

The high-temperature insulator 200 may be formed of an insulator layer having a single thickness, but may include insulator layers having different thicknesses.

For example, the heat insulating structure 1 includes a low-temperature insulating part 100 formed by stacking a first insulating material layer having a thickness of 5 mm to 10 mm on the outer surface of the tank body, and a thickness on the low-temperature insulating part 100. It may include;

The high-temperature insulating part 200 includes a first high-temperature insulating part formed by being laminated with a second insulating material layer having a thickness of 15 mm to 25 mm and a second high-temperature insulating part formed by being laminated with a second insulating layer having a thickness of 25 mm to 35 mm. can do.

In the insulation structure 1 of the liquefied gas tank according to an embodiment, a thinner insulation layer may be formed toward the tank side from the outside, thereby minimizing the occurrence of cracks due to the difference in shrinkage with the tank storing the liquid gas. can do.

The high-temperature insulator 200 may have a thickness of 300 mm to 500 mm.

4 is a view schematically showing a thermal insulation structure of a liquefied gas tank according to another embodiment.

As shown in FIG. 4 , the heat insulating structure 1 of the liquefied gas tank according to an embodiment may further include a coating layer 300 disposed on the high temperature heat insulating part 200.

The coating layer 300 may include one or more materials selected from the group consisting of polyurea, stainless steel, glass fiber reinforced plastic, glass fiber impregnated plastic, butyl rubber, and polyethylene rubber.

The coating layer 300 may be configured to prevent inflow of moisture from an external environment.

The coating layer 300 may have a thickness of 0.4 mm to 5 mm.

If the thickness of the coating layer is less than 0.4 mm, a problem of not being able to protect against impact may occur, and if it exceeds 5 mm, a problem of increasing weight or cost may occur.

The insulation structure 1 of the liquefied gas tank according to an embodiment is disposed between the low-temperature insulation unit 100 and the high-temperature insulation unit 200, or disposed on the high-temperature insulation unit 200, or both of the above positions. A reinforcing material layer 400 including a crack arrester disposed on the; may further include.

In the insulation structure of a tank storing LNG or LEG, when the temperature inside the tank becomes very low, the tank steel plate greatly shrinks, and stress is applied to the insulation structure due to the difference in expansion coefficient, and the insulation structure is delaminated from the surface of the tank. ) or cracks may occur in the insulation structure, which may reduce the insulation effect.

Insulation structure 1 according to an embodiment significantly reduces the occurrence of cracks through the low-temperature insulation part 100, and for cracks generated in the low-temperature insulation part 100, by the guarantee material layer 400. Propagation to the high-temperature insulation unit 200 and the coating layer 300 can be effectively blocked, and through this, the insulation effect can be remarkably improved.

The reinforcing material may include at least one selected from the group consisting of a glass fiber mesh, a basalt mesh, a carbon mesh, a nylon mesh, a wire mesh, and a fiber mesh.

The tensile force of the reinforcing member may be 500 N to 2000 N. If the tensile force of the reinforcing material) is less than 500 N, the reinforcing material may be damaged by the foaming force of the first or second insulating material such as polyurethane foam formed by spraying, and the tensile strength of the reinforcing material exceeds 2000 N In this case, foaming of the first insulator or the second insulator such as polyurethane foam may be hindered.

At this time, the tensile force of the reinforcing material may be measured by measuring the force at the point at which the reinforcing material is broken when the reinforcing material is cut into a size of 50 mm × 200 mm and then holding the 50 mm portion at both ends and applying force to one side.

The reinforcing material layer 400 may have a thickness of 0.3 mm to 3 mm.

If the thickness of the reinforcing material is less than 0.3 mm, it may be difficult to effectively control the spread of cracks, and if the thickness of the reinforcing material exceeds 3 mm, the density and insulation performance of the insulation structure may be affected. problems that may arise.

As shown in FIG. 4 , the insulation structure 1 of the liquefied gas tank according to an embodiment may include a low-temperature portion reinforcement layer 401 disposed between the low-temperature insulation portion 100 and the high-temperature insulation portion 200. and a high-temperature part reinforcement layer 402 disposed on the high-temperature heat insulating part 200.

As shown in FIG. 4, the insulation structure 1 of the liquefied gas tank according to an embodiment is by disposing a low-temperature reinforcing layer 401 between the low-temperature insulation portion 100 and the high-temperature insulation portion 200, so that the low-temperature insulation portion ( 100) can block propagation of physical damage such as cracks to the high-temperature insulator 200, and by disposing the high-temperature reinforcing layer 402 on the high-temperature insulator 200, the high-temperature insulator 200 ) can prevent physical damage such as cracks from propagating to the coating layer and the outside, and propagation of cracks caused by external force from the outside of the tank to the inside can also be effectively blocked.

Meanwhile, the thermal conductivity of the reinforcing material layer 400 is similar to that of the insulating material layer included in the heat insulating structure, and thus, by applying the reinforcing material, crack diffusion may be effectively controlled and at the same time, heat insulating performance may not be deteriorated.

The insulation structure 1 of the liquefied gas tank according to an embodiment may further include a primer adhesive layer 500 disposed between the outer surface of the tank and the low-temperature insulation part.

The primer adhesive layer 500 is configured to increase the adhesive strength of the tank surface and the low-temperature insulator 100, and the low-temperature insulator 100 is connected to the tank due to a difference in shrinkage rate from the tank at a cryogenic temperature by the primer adhesive layer 500. peeling from the surface can be prevented, and the occurrence of cracks can also be reduced.

In addition, the surface of the tank and the low-temperature insulator 100 can be uniformly adhered to each other through the primer adhesive layer 500, and deterioration in bar adhesion that may occur depending on the condition or skill of the operator can be minimized.

The primer adhesive layer 500 may be composed of different materials according to the constituent materials of the heat insulating material layer 10 constituting the low-temperature heat insulating part 100 .

For example, when the insulation layer 10 constituting the low-temperature insulation unit 100 is made of polyurethane foam, the primer adhesive layer 50 may be made of polyurethane foam primer.

On the other side,

As a method of forming a thermal insulation structure of the liquefied gas tank,

Forming a heat insulating structure by laminating a heat insulating material layer a plurality of times through spray coating on the outer surface of the tank body; includes,

At least a portion of the tank body side of the heat insulating structure includes a plurality of heat insulating layers having a thickness of 5 mm to 10 mm, a method for forming a heat insulating structure of a liquefied gas tank is provided.

Hereinafter, a method of forming a thermal insulation structure of a liquefied gas tank according to an embodiment will be described in detail for each step.

A method of forming a heat insulation structure of a liquefied gas tank according to an embodiment includes forming a heat insulation structure by stacking a plurality of layers of heat insulation material on an outer surface of a tank body through spray coating.

In this case, the heat insulating material constituting the heat insulating material layer may be preferably polyurethane foam (PU foam), and the density of the polyurethane foam may be 10 kg/m ³ to 100 kg/m ³ Yes, preferably 20 kg/m ³ to 80 kg/m ³ , more preferably 20 kg/m ³ to 60 kg/m ³ , and more preferably 30 kg/m ³ to 50 kg /m can be ³ .

In the method of forming the insulating structure of the liquefied gas tank according to an embodiment, a skin layer having a lower porosity may be naturally formed on the surface of the insulating material layer in the process of forming the insulating material layer through spray coating.

In the step of forming the heat insulating structure, at least a portion of the tank body side, more specifically, at least a portion of the heat insulating material layer in the thickness direction from one end of the tank side includes a plurality of thin heat insulating material layers having a thickness of 5 mm to 10 mm. Through this, the mechanical strength of the area adjacent to the tank body can be further improved by forming the skin layer every 5 mm to 10 mm in the thickness direction.

If the thickness of the first insulating material layer is less than 5 mm, the thickness is very thin and it is difficult to uniformly manufacture the spray method. When the thickness of the first insulating material layer exceeds 10 mm, the low temperature Since the mechanical strength of the heat insulating part is insufficient, the effect of preventing cracks from occurring may be insufficient due to a difference in shrinkage from a tank storing liquid gas at a cryogenic temperature.

The thickness of at least a part of the tank body side may be 20 mm or more, preferably 20 mm to 100 mm, preferably 30 mm to 60 mm, and more preferably 45 mm to 55 mm.

If the thickness of the region where the insulating material layer is formed with a thickness of 5 mm to 10 mm is less than 20 mm, the degree of improvement in the mechanical strength of the insulating structure is insufficient, resulting in cracks due to a difference in shrinkage with a tank storing liquid gas at a cryogenic temperature. The effect of preventing occurrence may be insufficient, and if the thickness of the area where the insulation layer having a thickness of 5 mm to 10 mm is formed exceeds 100 mm, the material requirement increases and a lot of time is invested in the work, resulting in a long construction period and manufacturing A problem of reduced efficiency may occur.

A method of forming a thermal insulation structure of a liquefied gas tank according to another embodiment

Forming a low-temperature heat insulating part by laminating a heat insulating material layer having a thickness of 5 mm to 10 mm; and

Forming one or more high-temperature insulation parts on the low-temperature insulation part; may include.

In this case, the heat insulating part is formed by stacking a heat insulating material layer thicker than the heat insulating material layer of the low temperature heat insulating part.

For example, the low-temperature part may be formed by stacking a first insulating material layer having a thickness of 5 mm to 10 mm, and the high-temperature insulating part may be formed by stacking a second insulating material layer having a thickness of 15 mm to 40 mm on the low-temperature insulating part.

In this case, the components and densities of the first insulating material layer and the second insulating material layer may be the same.

For example, the first insulating material layer and the second insulating material layer may be made of polyurethane foam having a density of 30 kg/m3 to 50 kg/m3.

In the method of forming the insulation structure of the liquefied gas tank according to an embodiment, a plurality of insulation layers having a thickness of 5 mm to 10 mm may be laminated on the low-temperature insulation unit 100 to form a sufficient number of skin layers 11, through which the liquefaction By improving the mechanical strength of the area adjacent to the gas tank, it is possible to significantly reduce the generation of cracks due to stress caused by a difference in shrinkage with the tank.

In addition, the method of forming a heat insulation structure of a liquefied gas tank according to an embodiment is formed by forming a heat insulating material layer made of a heat insulating material having the same density with different thicknesses, more preferably at least a portion of the tank body to a thickness of 5 mm to 10 mm, The mechanical strength of at least a part of the structure on the side of the tank body can be further improved.

In the step of forming the high-temperature insulation unit, one or more, preferably two or more high-temperature insulation units may be formed.

The high-temperature insulator may be formed of a single-thickness insulating material layer, but may include insulating material layers having different thicknesses.

For example, the high-temperature insulating part may include a first high-temperature insulating part formed by laminating a second insulating material layer having a thickness of 15 mm to 25 mm and a second high-temperature insulating part formed by laminating a second insulating layer having a thickness of 25 mm to 35 mm. can

The method of forming a thermal insulation structure of a liquefied gas tank according to an embodiment may further include forming an adhesive primer layer on an outer surface of the tank body.

The insulating material layer formed to a thickness of 5 mm to 10 mm may be applied to the outer surface of the liquefied gas tank body, but preferably may be applied on the primer adhesive layer.

The method of forming the insulation structure of the liquefied gas tank according to an embodiment may further include forming a low-temperature reinforcing material layer between the low-temperature insulation part and the high-temperature insulation part, and forming a high-temperature reinforcing material layer on the high-temperature insulation part. It may further include;

In the method of forming the insulation structure of the liquefied gas tank according to an embodiment, a low-temperature guaranteeing material layer is formed between the low-temperature insulation portion and the high-temperature insulation portion, thereby effectively preventing cracks that may occur in the low-temperature insulation portion from propagating to the high-temperature insulation portion. By forming a high-temperature reinforcing material layer on the high-temperature insulating part, it is possible to block physical damage such as cracks generated in the high-temperature insulating part from propagating to the outside, and cracks caused by external force from the outside of the tank propagate to the inside can also effectively block

The method of forming a thermal insulation structure of a liquefied gas tank according to an embodiment may further include forming a coating layer on the high-temperature thermal insulation unit.

The coating layer may preferably be formed on the high-temperature reinforcing material layer.

The coating layer may be formed of at least one material selected from the group consisting of polyurea, stainless steel, glass fiber reinforced plastic, glass fiber impregnated plastic, butyl rubber, and polyethylene rubber.

On the other side,

As a method of manufacturing the heat insulation structure of the liquefied gas tank,

Forming a heat insulating structure by laminating a heat insulating material layer a plurality of times through spray coating on the outer surface of the tank body; includes,

At least a portion of the tank body side of the insulating structure includes a plurality of insulating layers having a thickness of 5 mm to 10 mm, a method for manufacturing a liquefied gas tank is provided.

A method of manufacturing a liquefied gas tank according to an embodiment may include some or all of the components of the above-described method of forming a thermal insulation structure of a liquefied gas tank.

Hereinafter, the present invention will be described in detail through examples and experimental examples.

<Example 1>

Step 1: Spray polyurethane foam (PU foam) having a density of 40 kg/m ³ on the polyurethane foam primer 500 and laminate the first insulation layer with a thickness of about 10 mm in 6 layers to form an insulation structure with a thickness of about 60 mm. formed.

<Comparative Example 1>

Step 1: Spray polyurethane foam (PU foam) having a density of 40 kg/m ³ on the polyurethane foam primer 500 and laminate the first insulation layer with a thickness of about 30 mm into two layers to form an insulation structure with a thickness of about 60 mm. formed.

<Experimental Example 1>

For the insulation structures prepared in Example 1 and Comparative Example 1, tensile strength, compressive strength, and thermal conductivity were measured and are shown in Table 1 below.

At this time, the tensile strength was measured using the method of ASTM D1623, the compressive strength was measured using the method of ASTM D1621, and the thermal conductivity was measured by the method of ASTM C518.

item compressive strength tensile strength thermal conductivity Example 1 220 kPa 300 kPa 0.021W/mL Comparative Example 1 160 kPa 280 kPa 0.021W/mK

As shown in Table 1, the heat insulating structure of Example 1 in which the first heat insulating material layer having a thickness of about 10 mm is laminated in six layers is compared to the heat insulating structure of Comparative Example 1 in which the first heat insulating material layer having a thickness of about 30 mm is laminated in two layers. It can be seen that the compressive strength and tensile strength are excellent.

1: Insulation structure of liquefied gas tank
10: insulation layer
11: skin layer
100: low temperature insulation
20: insulation layer
200: high temperature insulation
300: coating layer
400: reinforcement layer
401: low temperature reinforcement layer
402: high-temperature reinforcement layer
500: primer adhesive layer
A: Liquefied gas tank

Claims (15)

A heat insulation structure formed by spraying on the outer surface of a tank body that accommodates liquefied gas therein,
It is formed by laminating a plurality of layers of insulating material made of polyurethane foam formed through spray coating on the outer surface of the tank body,
a low-temperature insulation part of the tank body side of the insulation structure having a thickness of 20 mm to 100 mm; and
Including; one or more high-temperature insulation parts formed on the low-temperature insulation part,
The low-temperature heat insulating part is formed by stacking a plurality of times a heat insulating material layer having a thickness of 5 mm to 10 mm,
The high-temperature heat insulating part is formed by laminating a heat insulating material layer having a thickness of 15 mm to 40 mm, the insulating structure of the liquefied gas tank.
delete According to claim 1,
The thickness of a portion of the tank body side of the heat insulating structure is 30 mm to 60 mm, the heat insulating structure of the liquefied gas tank.
According to claim 1,
The heat insulating structure of the liquefied gas tank, including a skin layer formed on the surface of the heat insulating material layer.
According to claim 1,
The thickness of the high-temperature insulation part is 300mm to 500mm, the insulation structure of the liquefied gas tank.
delete According to claim 1,
The low-temperature insulation part and the high-temperature insulation part made of a heat insulating material having the same density, the insulation structure of the liquefied gas tank.
delete According to claim 1,
The insulation structure is
The insulation structure of the liquefied gas tank further comprising a; coating layer disposed on the high-temperature insulation part.
According to claim 1,
The insulation structure is
A reinforcement layer disposed between the low-temperature insulation part and the high-temperature insulation part or on the high-temperature insulation part and including a crack arrester;
delete A method of forming a thermal insulation structure of the liquefied gas tank of claim 1,
Forming a heat insulating structure by laminating a heat insulating material layer made of polyurethane foam a plurality of times through spray coating on the outer surface of the tank body; includes,
The insulation structure is
a low-temperature insulation part of the tank body side of the insulation structure having a thickness of 20 mm to 100 mm; and
Including; one or more high-temperature insulation parts formed on the low-temperature insulation part,
The low-temperature heat insulating part is formed by stacking a plurality of times a heat insulating material layer having a thickness of 5 mm to 10 mm,
The method of forming a heat insulating structure for a liquefied gas tank, characterized in that the high temperature heat insulating part is formed by laminating a heat insulating material layer having a thickness of 15 mm to 40 mm.
delete According to claim 12,
A method of forming a thermal insulation structure of a liquefied gas tank, wherein the thickness of a partial area on the tank body side of the thermal insulation structure is 30 mm to 60 mm.
A method for manufacturing the heat insulation structure of the liquefied gas tank of claim 1,
Forming a heat insulating structure by laminating a heat insulating material layer made of polyurethane foam a plurality of times through spray coating on the outer surface of the tank body; includes,
The insulation structure,
a low-temperature insulation part of the tank body side of the insulation structure having a thickness of 20 mm to 100 mm; and
Including; one or more high-temperature insulation parts formed on the low-temperature insulation part,
The low-temperature heat insulating part is formed by stacking a plurality of times a heat insulating material layer having a thickness of 5 mm to 10 mm,
The method of manufacturing a liquefied gas tank, characterized in that the high-temperature heat insulating part is formed by laminating a heat insulating material layer having a thickness of 15 mm to 40 mm.

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