Double-layer heat insulation structure of ultralow-temperature liquid hydrogen centrifugal pump

Abstract

The utility model belongs to the technical field of low-temperature heat insulation, and particularly relates to a double-layer heat insulation structure of an ultralow-temperature liquid hydrogen centrifugal pump, which structurally comprises a pump main body, an inner cylinder, an outer cylinder, a first vacuum heat insulation interlayer and a second vacuum heat insulation interlayer, the pump main body, the inner cylinder and the outer cylinder are sequentially arranged from inside to outside, and a first cold insulation layer is formed between the inner cylinder and the pump main body; air is pumped between the outer cylinder and the inner cylinder to a vacuum state to form a second heat insulation layer; the first vacuum insulation interlayer is laid on the outer side wall of the inner cylinder, the inner side wall of the outer cylinder, the inner wall of the bottom of the outer cylinder and the inner wall of the part, not overlapped with the top of the inner cylinder, of the top of the outer cylinder. The first vacuum insulation interlayer is sequentially provided with a layer of insulation material and a layer of protection and holding material from inside to outside. The second vacuum heat insulation interlayer is laid on the outer wall of the bottom of the inner cylinder and sequentially provided with a heat insulation material, a protecting and holding material and an adsorption material from inside to outside. The first cold insulation layer is combined with the second heat insulation layer, so that a better heat insulation effect can be achieved in an ultralow-temperature liquid hydrogen storage environment.

Description

Technical Field

[0001] The utility model belongs to the technical field of low-temperature thermal insulation, and in particular relates to a double-layer thermal insulation structure of an ultra-low-temperature liquid hydrogen centrifugal pump. Background Art

[0002] Hydrogen energy is recognized worldwide as a clean energy with the advantages of zero carbon emissions, high energy density, and wide sources. Currently, hydrogen is widely used in many industries such as petrochemicals, semiconductor manufacturing, metallurgy, and aerospace rocket fuel.

[0003] Liquid hydrogen is a deep-cold hydrogen storage technology. Liquid hydrogen is a cryogenic liquid formed by hydrogen being compressed and cooled to -253°C. Its volume is reduced to 1 / 845 of its original gaseous state. It has a higher energy density and is easy to transport by ship and car.

[0004] In the process of liquid hydrogen production, storage, transportation, loading and unloading, and use, the liquid hydrogen pump is an indispensable key equipment. Since the storage environment of liquid hydrogen is -253℃, it is very easy to gasify due to temperature rise, resulting in waste of resources. Therefore, the insulation structure design of the liquid hydrogen pump is very important, and the existing single insulation layer structure design is difficult to meet the insulation requirements. Utility Model Content

[0005] In order to improve the deficiencies of the prior art, the utility model provides a double-layer insulation structure design of an ultra-low temperature liquid hydrogen centrifugal pump combining a cold insulation layer and a vacuum insulation layer, wherein the first cold insulation layer uses liquid hydrogen for cold insulation, and the second insulation layer has a second vacuum insulation interlayer of vacuum adsorption material and an opening device, which can achieve a better insulation effect in an ultra-low temperature liquid hydrogen storage environment.

[0006] The technical solution adopted by the utility model to solve the technical problem is: a double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump, including a pump body, an inner cylinder, an outer cylinder, a first vacuum insulation interlayer, and a second vacuum insulation interlayer, wherein:

[0007] The pump body, inner cylinder and outer cylinder are arranged in sequence from the inside to the outside. Liquid hydrogen is filled between the inner cylinder and the pump body to form a first cold insulation layer, and air is evacuated to a vacuum state between the outer cylinder and the inner cylinder to form a second heat insulation layer.

[0008] The first vacuum insulation interlayer is laid on the outer wall of the inner tube, the inner wall of the outer tube, the inner wall of the bottom of the outer tube, and the inner wall of the top of the outer tube that does not overlap with the top of the inner tube. The first vacuum insulation interlayer is sequentially provided with a layer of insulation material and a layer of supporting material from the inside to the outside;

[0009] The second vacuum insulation interlayer is laid on the outer wall of the bottom of the inner tube, and the second vacuum insulation interlayer is provided with a layer of insulation material, a layer of support material, and a layer of adsorption material from the inside to the outside in sequence;

[0010] Two interfaces are arranged at the bottom of the second vacuum insulation interlayer, one interface is connected to the vacuum flow channel pipe for extracting gas between the inner tube and the outer tube, and an opening device is installed at the other interface.

[0011] As a further preferred embodiment of the present invention, the inner cylinder includes an inner cylinder body, a sealing head, and two liquid hydrogen delivery ports. The inner cylinder body is arranged outside the pump body, a sealing head is arranged on the top of the inner cylinder body, and the two liquid hydrogen delivery ports are arranged at the bottom of the inner cylinder body.

[0012] As a further preference of the utility model, it also includes two liquid hydrogen delivery pipelines, one liquid hydrogen delivery pipeline leads from the external environment to the pump body through a liquid hydrogen delivery port, and the other liquid hydrogen delivery pipeline leads from the external environment to the space between the inner tube and the pump body through another liquid hydrogen delivery port.

[0013] As a further preferred embodiment of the present invention, the outer cylinder includes an outer cylinder body and an integrated flange end cover. The outer cylinder body is arranged outside the inner cylinder body, and an integrated flange end cover is arranged between the top of the inner cylinder body and the top of the outer cylinder body.

[0014] As a further preferred embodiment of the present invention, a triangular frame is provided between the bottom of the inner cylinder and the bottom of the outer cylinder.

[0015] As a further preferred embodiment of the present invention, the top of the triangular frame is welded to the inner cylinder, the bottom of the triangular frame is welded to the outer cylinder, and the bottom of the triangular frame is welded to the bottom of the outer cylinder.

[0016] As a further preferred embodiment of the present invention, the inner cylinder is made of austenitic stainless steel.

[0017] As a further preferred embodiment of the present invention, the outer cylinder is made of carbon steel or low alloy steel.

[0018] As a further preferred embodiment of the present invention, the contact between the vacuum flow channel tube and the outer cylinder is welded.

[0019] As a further preferred embodiment of the present invention, the opening device adopts a one-way valve.

[0020] Through the above technical solution, compared with the prior art, the utility model has the following beneficial effects:

[0021] Compared with the existing insulation layer structure, the utility model is a heat preservation design for liquid hydrogen centrifugal pumps. Since the storage environment of liquid hydrogen is extremely harsh, it needs to be in an environment of -253℃, and it is very easy to produce gasification due to temperature rise. Therefore, the structural design combining the first cold preservation layer (liquid hydrogen) and the second insulation layer (the second vacuum insulation interlayer with vacuum adsorption material and the opening device) is adopted, which can well maintain the ultra-low temperature environment of liquid hydrogen storage, achieve insulation effect, and reduce temperature rise. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0023] Figure 1 It is a cross-sectional schematic diagram of the utility model;

[0024] Figure 2 It is a state diagram of the utility model under actual working conditions;

[0025] Figure 3 It is a simple schematic diagram of the setting position of the second vacuum insulation interlayer of the utility model.

[0026] In the figure: 1. head; 2. pump body; 3. first vacuum insulation interlayer; 4. adsorption material; 5. triangular frame; 6. liquid hydrogen delivery pipeline; 7. vacuum flow channel pipe; 8. opening device; 9. outer cylinder; 10. inner cylinder; 11. liquid hydrogen; 12. integrated flange end cover; 13. second insulation layer; 14. second vacuum insulation interlayer. Implementation

[0027] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.

[0028] In the description of the present utility model, it should be understood that the terms "left side", "right side", "upper part", "lower part" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second" and the like do not indicate the importance of the components, and therefore cannot be understood as limiting the present invention. The specific dimensions used in this embodiment are only for illustrating the technical solution, and do not limit the scope of protection of the present invention. Example

[0029] This embodiment provides a preferred implementation scheme. Figures 1 to 3 As shown, a double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump, the insulation structure includes a pump body 2, an inner cylinder, an outer cylinder, a first vacuum insulation interlayer 3, and a second vacuum insulation interlayer 14, wherein:

[0030] The pump body 2, the inner tube and the outer tube are arranged in sequence from the inside to the outside. Liquid hydrogen 11 is filled between the inner tube and the pump body 2 to form a first cold insulation layer, and the air between the outer tube and the inner tube is evacuated to a vacuum state to form a second insulation layer 13.

[0031] The inner cylinder comprises an inner cylinder body 10, a sealing head 1, and two liquid hydrogen delivery ports. The inner cylinder body 10 is arranged outside the pump body 2, the sealing head 1 is arranged on the top of the inner cylinder body 10, and the two liquid hydrogen delivery ports are arranged at the bottom of the inner cylinder body 10. Preferably, the inner cylinder body 10 is made of austenitic stainless steel.

[0032] The outer cylinder comprises an outer cylinder body 9 and an integrated flange end cover 12. The outer cylinder body 9 is arranged outside the inner cylinder body 10, and an integrated flange end cover 12 is arranged between the top of the inner cylinder body 10 and the top of the outer cylinder body 9. Preferably, the outer cylinder body 9 is made of carbon steel or low alloy steel.

[0033] The first vacuum insulation interlayer 3 is laid on the outer wall of the inner tube, the inner wall of the outer tube, the inner wall of the bottom of the outer tube, and the inner wall of the outer tube top that does not overlap with the inner tube top. The first vacuum insulation interlayer 3 is sequentially provided with a layer of insulation material and a layer of support material from the inside to the outside. From the inside to the outside here means that the insulation material in the first vacuum insulation interlayer 3 laid on the outer wall of the inner tube is arranged close to the outer wall of the inner tube, and the support material is arranged away from the outer wall of the inner tube; the insulation material in the first vacuum insulation interlayer 3 laid on the inner wall of the outer tube is arranged close to the inner wall of the outer tube, and the support material is arranged away from the inner wall of the outer tube; the insulation material in the first vacuum insulation interlayer 3 laid on the inner wall of the bottom of the outer tube is arranged close to the inner wall of the bottom of the outer tube, and the support material is arranged away from the inner wall of the bottom of the outer tube; the insulation material in the first vacuum insulation interlayer 3 laid on the inner wall of the top of the outer tube that does not overlap with the inner tube top is arranged close to the inner wall of the top of the outer tube, and the support material is arranged away from the inner wall of the top of the outer tube.

[0034] The second vacuum insulation interlayer 14 is laid on the outer wall of the bottom of the inner tube. The second vacuum insulation interlayer 14 is provided with a layer of insulation material, a layer of support material, and a layer of adsorption material 4 from the inside to the outside. Here, from the inside to the outside means that the insulation material in the second vacuum insulation interlayer 14 is arranged close to the outer wall of the bottom of the inner tube, and the adsorption material 4 is arranged away from the outer wall of the bottom of the inner tube. The adsorption material 4 can extend the vacuum life several times. The cryogenic adsorption material should be heated and exhaled (activated); this embodiment adopts a molecular sieve low-temperature adsorption material, which is close to the outer wall of the bottom of the inner tube and is cooled by the inner tube wall temperature of the first cold preservation layer.

[0035] Regarding the insulation material in the first vacuum insulation interlayer 3 and the second vacuum insulation interlayer 14, vacuum insulation panels, referred to as VIP panels, are used, which are composited by a filling core porous medium material and a polyester-based air-insulating structure; the supporting materials used in the first vacuum insulation interlayer 3 and the second vacuum insulation interlayer 14 include (cork, polystyrene foam, polyurethane, cow hair felt and wool felt) to prevent settling, loosening and falling off.

[0036] Since the adsorbent material 4 is placed in a closed second insulation layer 13 and will not be opened until the second insulation layer 13 is evacuated to a certain vacuum, an air pressure opening scheme is provided. Two interfaces are provided at the bottom of the second vacuum insulation interlayer 14, one interface is connected to the vacuum flow channel pipe 7 for extracting the gas between the inner tube and the outer tube through a pipeline, and an opening device 8 is installed at the other interface. After the vacuum flow channel pipe 7 passes through the outer tube wall, it needs to be welded at the wall penetration to ensure sealing; the second insulation layer 13 is evacuated through the vacuum flow channel pipe 7. The opening device 8 adopts a one-way valve. In the standby state, the opening device 8 is closed. When the vacuum flow channel pipe 7 evacuates the second insulation layer 13 to a certain vacuum, the opening device 8 is opened under the action of the air pressure, and the adsorbent material 4 starts to work. Specifically, when the second insulation layer 13 is evacuated to a vacuum state of 80%, the one-way valve will automatically open when the pressure reaches a critical point, and the adsorption material 4 in the second vacuum insulation interlayer 14 starts to work, so that the vacuum state in the second insulation layer 13 is maintained above 80% vacuum state.

[0037] This embodiment further includes two liquid hydrogen delivery pipelines 6, one liquid hydrogen delivery pipeline 6 leads from the external environment to the pump body 2 through a liquid hydrogen delivery port, and the other liquid hydrogen delivery pipeline 6 leads from the external environment to the space between the inner tube and the pump body 2 through another liquid hydrogen delivery port. The order of delivering liquid hydrogen 11 is to first fill it into the first cold insulation layer and then fill it into the pump body 2.

[0038] In this embodiment, a triangular frame 5 is arranged between the bottom of the inner cylinder 10 and the bottom of the outer cylinder 9. The top of the triangular frame 5 is welded to the inner cylinder 10, the bottom of the triangular frame 5 is welded to the outer cylinder 9, and the bottom of the triangular frame 5 is welded to the bottom of the outer cylinder 9. The function of the triangular frame 5 is to stabilize and save materials to form a vacuum chamber as large as possible.

[0039] Compared with the existing insulation layer structure, this embodiment is a heat preservation design for a liquid hydrogen 11 centrifugal pump. Since the storage environment of liquid hydrogen 11 is extremely harsh, it needs to be in an environment of -253°C, and it is very easy to produce gasification due to temperature rise. Therefore, the structural design combining the first cold preservation layer (liquid hydrogen 11) and the second insulation layer 13 (the second vacuum insulation interlayer 14 with vacuum adsorption material 4 and the opening device 8) can well maintain the ultra-low temperature environment of liquid hydrogen 11 storage, achieve insulation effect, and reduce temperature rise.

[0040] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0041] The meaning of "and / or" described in this application means that the situations where each exists alone or both exist at the same time are included.

[0042] The term “connection” as used in this application may mean a direct connection between components or an indirect connection between components via other components.

[0043] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without deviating from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump, characterized in that: It comprises a pump body (2), an inner tube, an outer tube, a first vacuum insulation interlayer (3), and a second vacuum insulation interlayer (14), wherein: The pump body (2), the inner tube, and the outer tube are arranged in sequence from the inside to the outside, the space between the inner tube and the pump body (2) is filled with liquid hydrogen (11) to form a first cold insulation layer, and the space between the outer tube and the inner tube is evacuated to a vacuum state to form a second heat insulation layer (13); The first vacuum insulation interlayer (3) is laid on the outer wall of the inner tube, the inner wall of the outer tube, the inner wall of the bottom of the outer tube, and the inner wall of the outer tube top that does not overlap with the inner tube top. The first vacuum insulation interlayer (3) is provided with a layer of insulation material and a layer of support material in sequence from the inside to the outside; The second vacuum heat-insulating interlayer (14) is laid on the outer wall of the bottom of the inner tube, and the second vacuum heat-insulating interlayer (14) is provided with a layer of heat-insulating material, a layer of supporting material, and a layer of adsorbent material (4) in sequence from the inside to the outside; Two interfaces are provided at the bottom of the second vacuum insulation interlayer (14), one interface is connected to a vacuum flow channel pipe (7) for extracting gas between the inner tube and the outer tube, and an opening device (8) is installed at the other interface; The molecular sieve low-temperature adsorption material (4) is closely attached to the outer wall of the bottom of the inner tube and is cooled by the inner tube wall temperature of the first cold insulation layer.

2. The double-layer thermal insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 1 is characterized in that: The inner cylinder comprises an inner cylinder body (10), a sealing head (1), and two liquid hydrogen delivery ports. The inner cylinder body (10) is arranged outside the pump body (2), the sealing head (1) is arranged at the top of the inner cylinder body (10), and the two liquid hydrogen delivery ports are arranged at the bottom of the inner cylinder body (10).

3. The double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 2 is characterized in that: It also includes two liquid hydrogen delivery pipelines (6), one liquid hydrogen delivery pipeline (6) leading from the external environment to the pump body (2) through a liquid hydrogen delivery port, and the other liquid hydrogen delivery pipeline (6) leading from the external environment to the space between the inner cylinder and the pump body (2) through another liquid hydrogen delivery port.

4. The double-layer thermal insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 2 is characterized in that: The outer cylinder comprises an outer cylinder body (9) and an integrated flange end cover (12); the outer cylinder body (9) is arranged outside the inner cylinder body (10), and the integrated flange end cover (12) is arranged between the top of the inner cylinder body (10) and the top of the outer cylinder body (9).

5. The double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 2 is characterized in that: A triangular frame (5) is provided between the bottom of the inner cylinder (10) and the bottom of the outer cylinder (9).

6. The double-layer thermal insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 5 is characterized in that: The top of the triangular frame (5) is welded to the inner cylinder (10), the bottom of the triangular frame (5) is welded to the outer cylinder (9), and the bottom of the triangular frame (5) is welded to the bottom of the outer cylinder (9).

7. The double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 2 is characterized in that: The inner cylinder (10) is made of austenitic stainless steel.

8. The double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 4 is characterized in that: The outer cylinder (9) is made of carbon steel or low alloy steel.

9. The double-layer insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 4 is characterized in that: The contact between the vacuum flow channel tube (7) and the outer cylinder (9) is welded.

10. The double-layer thermal insulation structure of an ultra-low temperature liquid hydrogen centrifugal pump according to claim 1 is characterized in that: The opening device (8) adopts a one-way valve.

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