Combined cold insulation layer

Abstract

A combined cold insulation layer relates to the technical field of equipment and pipeline cold insulation and comprises a vacuum adjusting layer, a matching layer used for stabilizing the vacuum adjusting layer, a combined layer used for cold insulation and a protective layer used for collision protection which are sequentially distributed from inside to outside. The vacuum adjusting layer is a hollow structure layer used for adapting to deformation of a cold insulation object. The combined layer is composed of hard layers and flexible layers or composed of single flexible layers, and when the combined layer is composed of the hard layers and the flexible layers, the hard layers and the flexible layers are alternately distributed from inside to outside. The cold insulation effect of the cold insulation layer is maintained on the basis of adapting to deformation displacement of the cold insulation object.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment and pipeline cold preservation, in particular to a combined cold preservation layer. Background Art

[0002] There are a large number of cryogenic equipment and pipelines in the petrochemical and liquefied natural gas (LNG) industries. In order to reduce the energy consumption of maintaining the temperature during operation, a cold insulation layer needs to be set on the surface of cryogenic equipment and pipelines, i.e., cold insulation. The cold insulation layer reduces the cold loss of equipment and pipelines, i.e., cold insulation, so that the energy consumption used by the cold insulation to maintain the temperature required by the production process is lower. The cold insulation layer can also prevent workers from direct contact with the cold insulation, thereby reducing the probability of workers being injured by the low temperature of the cold insulation.

[0003] Most existing cold insulation layers are made of a single material. When a single material is deformed or displaced due to thermal expansion and contraction, impact, vibration, etc. in a pipeline or equipment, that is, the cold insulation material, it will mostly crack, that is, a large number of through cracks from the inside to the outside will appear on the surface of the cold insulation layer. After the cold insulation layer collapses and a large number of through cracks appear, the cold insulation effect of the cold insulation layer will drop sharply. Water vapor in the air enters through the cracks, condenses and freezes after contacting the cold wall surface of the cold insulation material, thereby accelerating the damage of the cold insulation layer. In addition, condensation and icing will further corrode and damage the equipment pipelines and steel structures, which is not conducive to the long-term safe and stable operation of the device. Utility Model Content

[0004] The utility model aims to provide a combined cold-keeping layer, so as to maintain the cold-keeping effect of the cold-keeping layer on the basis of adapting to the deformation and displacement of the cold-keeping object.

[0005] In order to solve the above technical problems, the specific solution adopted by the utility model is:

[0006] A combined cold-keeping layer comprises a vacuum adjustment layer, a matching layer for stabilizing the vacuum adjustment layer, a combined layer for cold-keeping and a protective layer for protecting against impact, which are sequentially distributed from the inside to the outside;

[0007] The vacuum adjustment layer is a hollow structure layer used to adapt to the deformation of the cold preservation object;

[0008] The combined layer is composed of a hard layer and a flexible layer, or is composed of a single flexible layer. When the combined layer is composed of a hard layer and a flexible layer, the hard layer and the flexible layer are alternately distributed from inside to outside.

[0009] As a further optimization of the combined cold-insulating layer of the utility model, the combined layer is composed of a hard layer and a flexible layer, and the matching layer is made of a diene elastomer foam material or a nitrile rubber foam material.

[0010] As a further optimization of the combined cold-insulating layer of the utility model, the flexible layer is made of nitrile rubber foam material, and the hard layer is made of foam glass.

[0011] As a further optimization of the combined cold-insulating layer of the utility model, the combined layer is composed of a single flexible layer, and the matching layer is made of foam glass carved by 3D scanning.

[0012] As a further optimization of the combined cold-insulating layer of the utility model, the flexible layer is made of diene elastomer foaming material and nitrile rubber foaming material combined from the inside to the outside.

[0013] As a further optimization of the combined cold-insulating layer of the utility model, the flexible layer is made of nitrile rubber foam material.

[0014] As a further optimization of the combined cold-keeping layer of the utility model, the hollow structure of the vacuum adjustment layer is in the shape of a rectangular staggered shape, a diamond honeycomb shape, a hollow corrugated shape or a hollow corrugated shape.

[0015] As a further optimization of the combined cold-insulating layer of the utility model, the protective layer is made of polyethylene, aluminum alloy plate or galvanized thin steel plate.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] This novel method reduces the thermal conductivity of the cold storage object by setting a vacuum adjustment layer as a hollow structure layer. At the same time, the vacuum adjustment layer can use its hollow structure to achieve its own deformation, thereby adapting to the deformation and displacement caused by thermal expansion and contraction and vibration of the cold storage object. At the same time, the interlaced distribution of the hard layer and the flexible layer can cooperate with the vacuum adjustment layer to better adapt to the deformation and displacement caused by thermal expansion and contraction, impact, and vibration of the cold storage object, and can also provide excellent cold storage effect. Therefore, when the cold storage object changes due to external factors and causes its own displacement and deformation, the cold storage layer can maintain an excellent cold storage effect, that is, reduce the probability of the cold storage layer breaking when the cold storage object is deformed.

[0018] The utility model sets a matching layer to keep the position of the vacuum adjustment layer stable, and then cooperates with the expansion and contraction performance of the vacuum adjustment layer to make it fit more completely with the cold preservation object, so as to reduce the possibility of mutual friction between the cold preservation object and the vacuum adjustment layer, so that the staff does not need to apply wear-resistant agent during the construction process, thereby shortening the construction process and construction time. After reducing the construction process, the construction speed will be increased, thereby reducing the construction cost and the condensation problem caused by the cold preservation object contacting the outside world for a long time during online construction.

[0019] As a further optimization of the utility model, by adopting 3D scanning carved foam glass to be applied to the special-shaped parts of the cold-keeping object, the matching layer has the advantages of high processing precision, close fit with the surface of the special-shaped part and fewer seams, thereby effectively ensuring the cold-keeping effect of the cold-keeping layer on the special-shaped part. At the same time, the 3D scanning carved foam glass of the special-shaped part can reduce the seams between itself and other flat parts, thereby reducing the construction difficulty of the special-shaped part and the probability of cracking and failure of the special-shaped part. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the cross-sectional structure of the utility model;

[0021] Figure 2 The utility model is a schematic diagram of the process structure of the combination method selection.

[0022] Figure numerals: 1. cold-keeping material, 2. vacuum adjustment layer, 3. matching layer, 4. combined layer, 401. flexible layer, 402. hard layer, 5. protective layer. DETAILED DESCRIPTION

[0023] like Figure 1 As shown, the utility model includes a vacuum adjustment layer 2, a matching layer 3, a combination layer 4 and a protective layer 5 which are sequentially distributed from the inside to the outside. The vacuum adjustment layer 2 is used to adapt to the deformation displacement of the cold preservation object 1, and the combination layer 4 and the matching layer 3 can cooperate with the vacuum adjustment layer 2 to adapt to the deformation displacement of the cold preservation object 1, thereby achieving the purpose of maintaining the cold preservation effect of the cold preservation object 1 on the basis of adapting to the deformation displacement of the cold preservation object.

[0024] The vacuum adjustment layer 2 is made of a hollow structural layer, and the shape of the hollow structural layer is a rectangular staggered shape, a diamond honeycomb shape, a hollow corrugated shape or a hollow corrugated shape. The setting of the vacuum adjustment layer 2 can adapt to the unevenness of the cold insulation surface of the cold insulation object 1, that is, the cold wall surface, due to its shape, such as the unevenness of the cold insulation weld and the unevenness caused by the ice that has not been thoroughly cleaned on the cold wall surface. The vacuum adjustment layer 2 uses the hollow structural layer inside it to form a situation where air and materials are alternately composed, thereby reducing the overall thermal conductivity of the cold insulation layer, and uses its hollow shape to improve the moisture-proof and waterproof performance of the cold insulation layer. At the same time, the elasticity of the vacuum adjustment layer 2 structure is used to adapt to the expansion and contraction of the cold insulation object 1 and the deformation and displacement caused by the vibration.

[0025] The matching layer 3 is made of a flexible material or foam glass carved by 3D scanning. When the matching layer 3 is a flexible material, it is applied to a flat part, and the vacuum adjustment layer 2 can be stably connected to the surface of the cold preservation object 1, that is, the cold wall surface. The matching layer 3 is made of a flexible material and can also adapt to the expansion and contraction deformation of the vacuum adjustment layer 2, and completely fit with the connection of the vacuum adjustment layer 2, thereby greatly reducing the friction between the matching layer 3 and the vacuum adjustment layer 2. The setting of the matching layer 3 and the vacuum adjustment layer 2 also allows the vacuum adjustment layer 2 to be stably applied to the cold wall surface, thereby effectively avoiding the displacement friction between the cold preservation object 1 and the vacuum adjustment layer 2, so there is no need to apply a wear-resistant agent between the cold preservation object 1 and the vacuum adjustment layer 2, thereby improving the efficiency of the staff in constructing and installing the cold preservation layer. The matching layer 3 is made of a flexible material, which can also reduce the generation of seams during the construction of the cold preservation layer. When the matching layer 3 is made of foam glass carved by 3D scanning, it is applied to special-shaped parts. At this time, due to the high processing accuracy of its material, the matching layer 3 can make the vacuum adjustment layer 2 completely fit on the cold wall surface of the cold-insulating object 1, thereby reducing the friction between the two. That is, there is no need to apply wear-resistant agent, and it will also reduce the generation of seams during the construction of the cold-insulating layer in special-shaped parts.

[0026] When the combined layer 4 is composed of a hard layer 402 and a flexible layer 401, it is applied to a flat part, or when it is composed of a single flexible layer 401, it is applied to a shaped part. When the combined layer 4 is composed of a flexible layer 401 and a hard layer 402, the two are alternately distributed from the inside to the outside. The alternating distribution of the flexible layer 401 and the hard layer 402 can reduce the friction between the two, that is, reduce the friction damage between the two, so there is no need to apply a wear-resistant agent between the combined layers 4, thereby further improving the efficiency of the workers in constructing and installing the cold insulation layer. After speeding up the construction efficiency, the construction cost and the condensation caused by online construction will be reduced.

[0027] The provision of the flexible layer 401 can further reduce the joints generated during the construction of the cold insulation layer, and can also facilitate the workers to quickly fit the hard layer 402 during construction to complete the construction process, thereby accelerating the efficiency of the workers in installing the cold insulation layer. The hard layer 402 has a small expansion coefficient and a low thermal conductivity, so it can effectively ensure the anti-aging and fireproof properties of the insulation structure.

[0028] like Figure 2As shown, when used in a flat area, the combined layer 4 is composed of a flexible layer 401 and a hard layer 402 alternately combined from the inside to the outside. When the medium temperature is less than or equal to -50°C, the matching layer 3 is made of a diene elastomer foam material with a lower applicable temperature, thereby maintaining a good cold insulation effect of the entire cold insulation layer. When the medium temperature is greater than -50°C, the matching layer 3 is made of a low-priced and economical nitrile rubber foam material, thereby reducing the cost of constructing and installing the cold insulation layer, and the flexible layer 401 is made of nitrile rubber foam material, and the hard layer 402 is made of foam glass. The above settings can make the entire cold insulation layer well adapt to the expansion and contraction of the equipment pipeline, the impact, and the deformation and displacement caused by vibration, that is, the overall structure of the cold insulation layer has good stability and applicability, while maintaining a relatively good cold insulation effect. And reduce the construction link of brushing wear-resistant agent, thereby shortening the construction process and time.

[0029] When used in a special-shaped part, the combined layer 4 is composed of a single flexible layer 401. The matching layer 3 is made of foam glass carved by 3D scanning. The matching layer 3 composed of foam glass carved by 3D scanning is an integrated special-shaped foam glass piece that is 3D carved based on the size and modeling information of the special-shaped part in a cold-tight state and after the construction of the vacuum adjustment layer 2. As a result, the matching layer 3 has the advantages of high processing accuracy, close fit with the surface of the special-shaped part, few joints, and can effectively ensure the insulation effect of the special-shaped part. When the medium temperature is less than or equal to -50°C, the flexible layer 401 is made of diene elastomer foam material and nitrile rubber foam material alternately distributed from inside to outside, thereby reducing the material cost while ensuring the cold preservation effect. When the medium temperature of the flexible layer 401 is greater than -50°C, the flexible layer 401 is made of nitrile rubber foam material, thereby maintaining a low cost of using the cold preservation layer.

[0030] The protective layer 5 is made of polyethylene, aluminum alloy plate or galvanized thin steel plate, thereby reducing the damage to the cold insulation layer caused by the top pressure of hard objects, and further improving the resistance of the cold insulation layer to the influence of external factors.

[0031] The following will further explain the utility model in combination with the specific construction situation: Specific embodiment 1

[0033] The ethylene unit of a certain refinery includes a cold-insulated pipeline with a diameter of φ325 and a medium design temperature of -98℃. Affected by the vibration of the connected pump, the cold-insulation layer is cracked and damaged. The outer surface of the cold-insulation layer is seriously condensed and moss is grown, resulting in large cold losses. The temperature of the downstream process medium cannot meet the production requirements, and the cold-insulation layer needs to be replaced online without stopping the work.

[0034] The online construction object is a flat area with a medium temperature less than or equal to -50°C, so the "combination structure of vacuum adjustment layer 2, matching layer 3, combined layer 4 composed of hard layer 402 and flexible layer 401 alternately distributed from inside to outside, and protective layer 5" is adopted, that is, the combination structure of "5mm vacuum adjustment layer 2, 30mm diene elastomer foam material, 50mm foam glass, 30mm nitrile rubber foam material and 50mm foam glass" is adopted, and the vacuum adjustment layer 2 adopts a hollow corrugated structure.

[0035] The cold insulation online construction adopts the construction method of dismantling and installing at the same time. During the dismantling and installation process, dry air is used to continuously blow the cold wall surface of the construction site pipeline to effectively prevent moisture in the air from contacting the cold wall surface of the low-temperature equipment pipeline and condensing and icing. At the same time, the joints of diene elastomer foaming materials, foam glass, and nitrile rubber foaming materials are bonded with special adhesives. Finally, the protective layer 5 is constructed.

[0036] After the construction was completed and the pipeline was in steady state operation for one month, the heat flow meter was used to test the cold loss of the outer surface of the cold insulation layer, which was 18W / m 2 The outer surface temperature of the cold insulation layer was tested with a point thermometer, and it was calculated that the outer surface temperature under the design conditions was 1.8°C higher than the dew point temperature, which met the requirements of cold loss, anti-condensation and process, thereby maintaining an excellent cold insulation effect on the basis of adapting to the deformation and displacement of the cold insulation material 1 caused by external factors. Specific embodiment 2

[0038] A liquefied natural gas company has a DN300 valve with a medium design temperature of -39°C. During operation, the cold insulation layer deforms and moves due to thermal expansion and contraction of the valve, resulting in through cracks. At the same time, the cold insulation layer needs to be disassembled for valve maintenance, so the online restoration of the cold insulation layer needs to be carried out without stopping the operation.

[0039] The online construction object is the special-shaped parts with the medium temperature greater than -50°C, so the combined structure of "vacuum adjustment layer 2, matching layer 3 made of 3D scanning and engraving foam glass, and combined layer 4 composed of a single flexible layer 401" is adopted, that is, "5mm vacuum adjustment layer 2, 100mm3D scanning and engraving foam glass, 30mm nitrile rubber foam material" is used to carry out construction on the special-shaped parts, and the vacuum adjustment layer 2 adopts a diamond honeycomb structure.

[0040] Use dry air to continuously blow the cold wall surface of the construction site. After using a copper shovel to remove ice from the cold wall surface of the valve, construct the vacuum adjustment layer 2, and perform 3D scanning on the irregular parts that are in the online cold-tight state and after the vacuum adjustment layer 2 is constructed. At the same time, record the relevant data and transmit it to the 3D engraving equipment. Then, based on the scanned size and modeling information of the irregular parts in the cold-tight state, 3D engraving processing is performed on the block foam glass as the basis. The processed 3D scanned and engraved foam glass is a double-layer irregular foam glass piece with an inner and outer thickness of 50mm respectively, and has the advantages of high precision and high fit with the irregular parts in the cold-tight state and after the vacuum adjustment layer 2 is constructed.

[0041] Afterwards, the inner layer of 50mm special-shaped foam glass pieces and the outer layer of 50mm special-shaped foam glass pieces are constructed layer by layer. The joints of the two petals of the inner layer of special-shaped foam glass pieces adopt a step overlap structure, and the joints of the two petals of the outer layer of special-shaped foam glass pieces adopt a concave-convex interlocking structure. The vacuum adjustment layer 2 and the matching layer 3 are spliced ​​together to form a splicing structure, and the joints of the two petals of the step and the concave-convex interlocking joints are bonded with adhesives. Finally, the construction and installation of the protective layer 5 are carried out.

[0042] After the construction was completed and the valve was running steadily for one month, the heat flow meter was used to test the cold loss of the outer surface of the cold insulation layer, which was 16.7W / m 2 , use a point thermometer to test the outer surface temperature of the cold insulation layer, and calculate that the outer surface temperature value under the design condition is 2.1℃ higher than the dew point temperature, which meets the requirements of cold loss, anti-condensation and process. In this way, the excellent cold insulation effect is maintained on the basis of adapting to the deformation and displacement of the cold insulation material 1 caused by external factors.

Claims

1. A combined cold insulation layer, characterized in that: It comprises a vacuum adjustment layer (2) distributed in sequence from the inside to the outside, a matching layer (3) for stabilizing the vacuum adjustment layer (2), a combination layer (4) for keeping cold, and a protective layer (5) for protecting against impact; The vacuum adjustment layer (2) is a hollow structure layer used to adapt to the deformation of the cold preservation object (1); The combined layer (4) is composed of a hard layer (402) and a flexible layer (401), or is composed of a single flexible layer (401). When the combined layer (4) is composed of a hard layer (402) and a flexible layer (401), the hard layer (402) and the flexible layer (401) are alternately distributed from the inside to the outside.

2. A combined cold insulation layer according to claim 1, characterized in that: The combined layer (4) is composed of a hard layer (402) and a flexible layer (401), and the matching layer (3) is made of diene elastomer foam material or nitrile rubber foam material.

3. A combined cold insulation layer according to claim 2, characterized in that: The flexible layer (401) is made of nitrile rubber foam material, and the hard layer (402) is made of foam glass.

4. A combined cold insulation layer according to claim 1, characterized in that: The combined layer (4) is composed of a single flexible layer (401), and the matching layer (3) is made of foam glass engraved by 3D scanning.

5. A combined cold insulation layer according to claim 4, characterized in that: The flexible layer (401) is made of diene elastomer foam material and nitrile rubber foam material combined from the inside to the outside.

6. A combined cold insulation layer according to claim 4, characterized in that: The flexible layer (401) is made of nitrile rubber foam material.

7. A combined cold insulation layer according to claim 1, characterized in that: The hollow structure of the vacuum adjustment layer (2) is in the shape of a rectangular staggered shape, a diamond honeycomb shape, a hollow corrugated shape or a hollow corrugated shape.

8. The combined cold insulation layer according to claim 1, characterized in that: The protective layer (5) is made of polyethylene, aluminum alloy plate or galvanized thin steel plate.

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