Liquid nitrogen refrigerating device

Abstract

The invention relates to the technical field of liquid nitrogen refrigeration, and provides a liquid nitrogen refrigeration device which comprises an outer layer barrel, a middle layer barrel, an exhaust barrel and a heat insulation device. The middle-layer cylinder is arranged in the vacuum cavity, a liquid storage cavity is formed in the middle-layer cylinder, and the liquid storage cavity is used for storing liquid nitrogen; a part of the exhaust cylinder is located in the vacuum cavity, and the exhaust cylinder communicates with the vacuum cavity and is used for exhausting gas in the vacuum cavity; and the heat insulation device is arranged between the middle-layer barrel and the exhaust barrel. According to the liquid nitrogen refrigeration device provided by the embodiment of the invention, the heat insulation performance of the liquid nitrogen refrigeration device can be improved, and the freezing probability of the liquid nitrogen refrigeration device is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of liquid nitrogen refrigeration, and in particular to a liquid nitrogen refrigeration device. Background Art

[0002] This section is intended to provide a background or context for the embodiments of the present application. No description herein is admitted to be prior art by virtue of its inclusion in this section.

[0003] A liquid nitrogen refrigeration device is a device that cools down a target object by absorbing heat from liquid nitrogen. In the related art, the outer surface of the liquid nitrogen refrigeration device is prone to ice and frost. Summary of the invention

[0004] In view of this, an embodiment of the present application hopes to provide a liquid nitrogen refrigeration device, which can improve the thermal insulation performance of the liquid nitrogen refrigeration device and reduce the probability of freezing of the liquid nitrogen refrigeration device.

[0005] The present application provides a liquid nitrogen refrigeration device, comprising:

[0006] An outer tube is formed with a vacuum cavity;

[0007] A middle cylinder is arranged in the vacuum chamber, and the middle cylinder is formed with a liquid storage chamber, and the liquid storage chamber is used to store liquid nitrogen;

[0008] An exhaust cylinder, part of which is located in the vacuum chamber, and the exhaust cylinder is in communication with the vacuum chamber to exhaust the gas in the vacuum chamber;

[0009] The heat insulation device is arranged between the middle tube and the exhaust tube.

[0010] In some embodiments, the heat insulation device includes a heat insulation board and a plurality of fastening structures, wherein the heat insulation board is arranged between the middle tube and the exhaust tube, some of the fastening structures connect the heat insulation board and the middle tube, and other parts of the fastening structures connect the heat insulation board and the exhaust tube.

[0011] In some embodiments, the heat insulation board forms a limiting hole, the fastening structure includes a main body and two adjusting parts, the middle tube and the exhaust tube are both connected to the corresponding main body, the main body is passed through the limiting hole and the two adjusting parts, the two adjusting parts are respectively located on both sides of the heat insulation board along the thickness direction, the two adjusting parts are used to lock or unlock the main body, wherein the hole wall surface of the limiting hole and the circumferential surface of the main body are spaced apart.

[0012] In some embodiments, the fastening structure includes a plurality of thermal insulation washers, each adjusting member corresponds to a thermal insulation washers, and the thermal insulation washers are clamped between the adjusting member and the thermal insulation board.

[0013] In some embodiments, the outer layer tube includes an outer tube body and a connecting piece, the outer tube body has an opening at one end along the axial direction, the connecting piece closes the axial opening of the outer tube body, the connecting piece forms a positioning hole connected to the vacuum chamber, and the hole wall surface of the positioning hole is sealed and connected to the outer wall surface of the exhaust tube.

[0014] In some embodiments, part of the exhaust tube is located inside the vacuum chamber, and another part of the exhaust tube is located outside the vacuum chamber, the exhaust tube forms an exhaust chamber, the portion of the exhaust tube located inside the vacuum chamber forms a flow hole, the flow hole connects the exhaust chamber and the vacuum chamber, and the portion of the exhaust tube located outside the vacuum chamber forms an air outlet, and the air outlet is connected to the exhaust chamber.

[0015] In some embodiments, the liquid nitrogen refrigeration device includes a connecting flange, there are multiple gas outlets, and the connecting flange is disposed on the outer side of at least one gas outlet, and the connecting flange is communicated with the corresponding gas outlet.

[0016] In some embodiments, the liquid nitrogen refrigeration device includes an inner cylinder, an air inlet pipe and an air outlet pipe, the inner cylinder is located in the liquid storage cavity, the inner cylinder forms an air storage cavity, and the air inlet pipe and the air outlet pipe are both connected to the air storage cavity.

[0017] In some embodiments, the diameter of the air inlet pipe is greater than the diameter of the air outlet pipe.

[0018] In some embodiments, the inner tube and the middle tube are both located above the exhaust tube, the air inlet pipe includes a first connecting port connected to the air storage chamber, the air outlet pipe includes a second connecting port connected to the air storage chamber, and the height of the first connecting port is lower than that of the second connecting port.

[0019] The liquid nitrogen refrigeration device provided in the embodiment of the present application has, on the one hand, a middle tube located in the vacuum chamber, and an exhaust tube exhausting the gas in the vacuum chamber, so that it is difficult for external heat to be transferred to the middle tube through the outer tube and the gas in the vacuum chamber and to exchange heat with the liquid nitrogen, which can effectively prevent the wall surface of the outer tube from freezing. On the other hand, the heat insulation device is located between the middle tube and the exhaust tube, and the middle tube and the exhaust tube are spaced apart, so it is difficult for external heat to be transferred to the middle tube through the exhaust tube. The heat insulation device can block the transfer of heat, further enhance the heat insulation performance of the liquid nitrogen refrigeration device, and reduce the chance of freezing of the liquid nitrogen refrigeration device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of a liquid nitrogen refrigeration device provided in some embodiments of the present application;

[0021] Figure 2A schematic diagram of the structure of the middle tube, the heat insulation device and the exhaust tube assembly provided in some embodiments of the present application;

[0022] Figure 3 A partial structural schematic diagram of a heat insulation device provided in some embodiments of the present application;

[0023] Figure 4 for Figure 1 Enlarged view of point A in the middle;

[0024] Figure 5 for Figure 1 Enlarged view of point B in the middle;

[0025] Figure 6 A schematic diagram of the structure of an air intake pipe provided in some embodiments of the present application;

[0026] Figure 7 A schematic diagram of the structure of an air outlet pipe provided in some embodiments of the present application.

[0027] Description of Reference Numerals

[0028] Liquid nitrogen refrigeration device 100;

[0029] Outer cylinder 10; vacuum chamber 10a; outer cylinder body 11; connecting piece 12; positioning hole 12a; outer sealing head 13;

[0030] Middle cylinder 20; liquid storage chamber 20a; middle end cap 21; middle cylinder body 22;

[0031] Exhaust cylinder 30; flow hole 30a; air outlet 30b; exhaust cavity 30c; first end cap 31; first cylinder body 32;

[0032] Heat insulation device 40; heat insulation board 41; limiting hole 41a; fastening structure 42; main body 421; adjusting member 422; heat insulation gasket 423;

[0033] Take over flange 50;

[0034] Inner layer cylinder 60; air storage chamber 60a; inner head 61; flow port 61a; inner cylinder body 62;

[0035] Inlet pipe 70; first communication port 70a; first air intake section 71; second air intake section 72; third air intake section 73;

[0036] The air outlet pipe 80; the second communication port 80a; the first air outlet section 81; the second air outlet section 82; the third air outlet section 83;

[0037] Support flange 90; fixing hole 90a. DETAILED DESCRIPTION

[0038] The following is a further detailed description of the implementation of the present application in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but cannot be used to limit the scope of the present application.

[0039] The various specific technical features and embodiments described in the specific implementation methods can be combined in any suitable manner without contradiction. For example, different implementation methods can be formed by combining different specific technical features / embodiments. In order to avoid unnecessary repetition, the various possible combinations of the specific technical features / embodiments in this application are no longer described separately. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. The application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0040] In the related art, a liquid nitrogen refrigeration device includes an outer cylinder and an inner cylinder. The outer cylinder cover is arranged on the outside of the inner cylinder. The inner cylinder is used to store liquid nitrogen. At least part of the outer wall surface of the inner cylinder is connected to the inner wall surface of the outer cylinder. The heat of the external heat source is transferred through the connection part between the outer cylinder and the inner cylinder and exchanges heat with the liquid nitrogen. The thermal insulation effect of the liquid nitrogen refrigeration device is poor, resulting in ice and frost at the connection part.

[0041] See also Figures 1 to 7 The embodiment of the present application provides a liquid nitrogen refrigeration device 100, including an outer tube 10, a middle tube 20, an exhaust tube 30 and an insulation device 40, the outer tube 10 forms a vacuum chamber 10a; the middle tube 20 is arranged in the vacuum chamber 10a, and the middle tube 20 forms a liquid storage chamber 20a, and the liquid storage chamber 20a is used to store liquid nitrogen; part of the exhaust tube 30 is located in the vacuum chamber 10a, and the exhaust tube 30 is connected to the vacuum chamber 10a to discharge the gas in the vacuum chamber 10a; the insulation device 40 is arranged between the middle tube 20 and the exhaust tube 30.

[0042] The liquid nitrogen refrigeration device 100 can be used to refrigerate raw gas. Raw gas refers to raw materials used to prepare synthesis gas or natural gas, such as CO (carbon monoxide), H2 (hydrogen), BF3 (boron trifluoride), etc.

[0043] The middle tube 20 is located in the vacuum chamber 10a. Figure 1 The outer wall of the middle tube 20 is spaced from the inner wall of the outer tube 10, and the middle tube 20 and the outer tube 10 are not in direct contact. In this way, it is difficult for external heat to be transferred to the middle tube 20 through the outer tube 10 and exchange heat with liquid nitrogen, which can effectively prevent the wall of the outer tube 10 from freezing.

[0044] The exhaust tube 30 is used to exhaust the gas in the vacuum chamber 10a. There may be no gas in the vacuum chamber 10a. In this way, external heat cannot be transferred to the middle tube 20 through the gas and exchange heat with the liquid nitrogen, thereby improving the thermal insulation performance of the liquid nitrogen refrigeration device 100.

[0045] The heat insulating device 40 is a structure capable of blocking heat transfer. For example, the heat insulating device 40 can block heat transfer by at least one of isolating a heat source and reducing heat dissipation.

[0046] See also Figure 2 The heat insulating device 40 is located between the middle tube 20 and the exhaust tube 30, that is, the middle tube 20 and the exhaust tube 30 are spaced apart, and the middle tube 20 and the exhaust tube 30 are not in direct contact. The heat insulating device 40 can increase the thermal resistance between the middle tube 20 and the exhaust tube 30, so that, on the one hand, it is difficult for external heat to be transferred to the middle tube 20 through the exhaust tube 30 and exchange heat with liquid nitrogen, and on the other hand, the heat insulating device 40 can block the transfer of heat, further enhance the heat insulating performance of the liquid nitrogen refrigeration device 100, and reduce the probability of icing of the liquid nitrogen refrigeration device 100.

[0047] In the liquid nitrogen refrigeration device 100 provided in the embodiment of the present application, on the one hand, the middle tube 20 is located in the vacuum chamber 10a, and the exhaust pipe 30 exhausts the gas in the vacuum chamber 10a. It is difficult for external heat to be transferred to the middle tube 20 through the outer tube 10 and the gas in the vacuum chamber 10a and to exchange heat with liquid nitrogen, which can effectively prevent the wall surface of the outer tube 10 from freezing. On the other hand, the heat insulation device 40 is located between the middle tube 20 and the exhaust pipe 30. The middle tube 20 and the exhaust pipe 30 are spaced apart, and it is difficult for external heat to be transferred to the middle tube 20 through the exhaust pipe 30. The heat insulation device 40 can block the transfer of heat, further enhance the heat insulation performance of the liquid nitrogen refrigeration device 100, and reduce the probability of freezing of the liquid nitrogen refrigeration device 100.

[0048] For some examples, see Figure 1 and Figure 2 The heat insulation device 40 includes a heat insulation board 41 and a plurality of fastening structures 42. The heat insulation board 41 is arranged between the middle tube 20 and the exhaust tube 30 at intervals. Some fastening structures 42 connect the heat insulation board 41 and the middle tube 20, and other parts of the fastening structures 42 connect the heat insulation board 41 and the exhaust tube 30.

[0049] The heat insulation board 41 plays a role in blocking heat transfer. On this basis, the heat insulation board 41 is spaced apart from the middle tube 20 and the exhaust tube 30, which can further improve the heat insulation performance of the liquid nitrogen refrigeration device 100.

[0050] As an example, the heat insulation board 41 may be a heat insulation structure having a low heat conductivity.

[0051] In this embodiment, the exhaust pipe 30 and the middle pipe 20 are respectively connected to different fastening structures 42, which can further extend the heat transfer path and increase the thermal resistance on the heat transfer path. The exhaust pipe 30 also supports the middle pipe 20 and can maintain the stability of the middle pipe 20.

[0052] The specific material of the heat insulation board 41 is not limited. The heat insulation board 41 can be made of a poor heat conductor. For example, the heat insulation board 41 can be made of S30408 ​​stainless steel material, which has a good heat insulation effect.

[0053] It should be noted that, in the present application, a plurality refers to a quantity including two or more.

[0054] In one embodiment, a plurality of fastening structures 42 are evenly spaced along the circumference of the heat insulation board 41, wherein one of two adjacent fastening structures 42 connects the heat insulation board 41 and the middle tube 20, and the other connects the heat insulation board 41 and the exhaust pipe 30. In this way, on the one hand, the forces between the middle tube 20, the heat insulation board 41 and the exhaust pipe 30 are relatively uniform, thereby improving the stability of the liquid nitrogen refrigeration device 100. On the other hand, the contact area between the fastening structure 42 and the middle tube 20 and the exhaust pipe 30 is small, which can reduce the heat transferred through the fastening structure 42.

[0055] In one embodiment, the thickness of the heat insulation board 41 is 5 mm (millimeter) to 15 mm. Exemplarily, the thickness of the heat insulation board 41 can be 5 mm, 7 mm, 9 mm, 11 mm, 13 mm or 15 mm, etc. In this way, both structural strength and heat insulation requirements can be taken into account.

[0056] In some embodiments, the fastening structure 42 may be detachably connected to the heat insulation board 41. Of course, the fastening structure 42 may also be non-detachably connected to the heat insulation board 41.

[0057] For some examples, see Figure 3 The heat insulation board 41 forms a limiting hole 41a, the fastening structure 42 includes a main body 421 and two adjusting members 422, the middle tube 20 and the exhaust tube 30 are both connected to the corresponding main body 421, the main body 421 is penetrated by the limiting hole 41a and the two adjusting members 422, the two adjusting members 422 are respectively located on both sides of the heat insulation board 41 along the thickness direction, and the two adjusting members 422 are used to lock or unlock the main body 421, wherein the hole wall surface of the limiting hole 41a and the circumferential surface of the main body 421 are spaced apart.

[0058] The limiting hole 41a limits the main body 421. The adjusting member 422 can move along the axial direction of the main body 421. By changing the position of the adjusting member 422, the two adjusting members 422 can clamp the two sides of the heat insulation board 41 along the thickness direction, thereby locking the main body 421 and realizing the fastening connection between the heat insulation board 41 and the middle tube 20 and the exhaust tube 30; or the two adjusting members 422 move away from the heat insulation board 41 along the axial direction of the main body 421, thereby releasing the main body 421, and facilitating the loading and unloading of the heat insulation board 41, the middle tube 20 and the exhaust tube 30.

[0059] The hole wall of the limiting hole 41a is spaced from the circumferential surface of the main body 421. That is, the main body 421 and the heat insulation board 41 are not in direct contact, so that heat is difficult to transfer to the heat insulation board 41 through the main body 421, thereby improving the heat insulation performance of the heat insulation device 40.

[0060] In one embodiment, the main body 421 may be a screw, and the adjusting member 422 may be a nut. The main body 421 and the adjusting member 422 are threadedly matched, which is convenient for operation.

[0061] For some examples, see Figure 3 The fastening structure 42 includes a plurality of heat-insulating washers 423, each adjusting member 422 corresponds to a heat-insulating washer 423, and the heat-insulating washers 423 are clamped between the adjusting member 422 and the heat-insulating plate 41. In this way, on the one hand, the heat-insulating washers 423 play a heat-insulating role, which can further reduce the heat conduction between the heat-adjusting member 422 and the heat-insulating plate 41. On the other hand, in the process of locking the main body 421, the heat-insulating washers 423 play a certain protective role in preventing the adjusting member 422 from exerting too much force on the heat-insulating plate 41 and causing damage.

[0062] The heat insulating gasket 423 may be made of a material with a small thermal conductivity, such as polytetrafluoroethylene.

[0063] For some examples, see Figure 1 The outer layer tube 10 includes an outer cylinder body 11 and a connecting piece 12. The outer cylinder body 11 has an opening at one end along the axial direction. The connecting piece 12 closes the axial opening of the outer cylinder body 11. The connecting piece 12 forms a positioning hole 12a connected to the vacuum chamber 10a. The hole wall surface of the positioning hole 12a is sealed and connected to the outer wall surface of the exhaust pipe 30.

[0064] For example, the connecting member 12 and the outer cylinder 11 can be manufactured separately, and the connecting member 12 can be sealed and connected to the exhaust pipe 30 first, and then the connecting member 12 can be assembled to the outer cylinder 11. In this way, the manufacturing difficulty is reduced.

[0065] The connector 12 is used to connect the exhaust tube 30. Through the cooperation between the exhaust tube 30 and the positioning hole 12a, part of the connector 12 is located in the vacuum chamber 10a. The hole wall of the positioning hole 12a is sealed with the outer wall of the exhaust tube 30, which can improve the sealing performance of the vacuum chamber 10a, ensure the reliability of the sealing, and enhance the connection stability between the exhaust tube 30 and the outer tube 10.

[0066] The hole wall surface of the positioning hole 12a and the outer wall surface of the exhaust pipe 30 are sealed in any manner, for example, the hole wall surface of the positioning hole 12a and the outer wall surface of the exhaust pipe 30 are welded. For another example, the hole wall surface of the positioning hole 12a and the outer wall surface of the exhaust pipe 30 are sealed by a sealing structure.

[0067] The connecting member 12 may be a connecting flange.

[0068] The specific material of the outer cylinder 11 is not limited. For example, the outer cylinder 11 can be made of S30408 ​​stainless steel material, which has a good heat insulation effect.

[0069] In one embodiment, the thickness of the outer cylinder 11 is 5 mm (millimeter) to 10 mm. Exemplarily, the thickness of the outer cylinder 11 can be 5 mm, 6 mm, 7 mm, 8 mm, 9 mm or 10 mm, etc.

[0070] In one embodiment, please refer to Figure 1 The outer cylinder 10 further includes an outer seal 13, which is disposed at an end of the outer cylinder 11 opposite to the connecting piece 12 in the axial direction, and the outer seal 13 is welded to the outer cylinder 11. That is, the outer seal 13, the outer cylinder 11 and the connecting piece 12 together define a vacuum chamber 10a.

[0071] During the operation of the liquid nitrogen refrigeration device 100, liquid nitrogen needs to be repeatedly filled into the liquid storage chamber 20a, which is prone to generate large temperature stress. By welding the outer seal 13 to the outer cylinder 11, the connection stability of the outer seal 13 and the outer cylinder 11 can be enhanced. At the same time, the sealing performance of the vacuum chamber 10a can be improved to ensure the reliability of the sealing. In addition, the outer seal 13 and the outer cylinder 11 can be designed and produced separately, reducing the manufacturing difficulty of the outer cylinder 10.

[0072] The specific material of the outer head 13 is not limited. For example, the outer head 13 can be made of S30408 ​​stainless steel material, which has a good heat insulation effect.

[0073] In one embodiment, please refer to Figure 1 The outer cover 13 is roughly semicircular, so that the interval between the middle layer cylinder 20 and the outer layer cylinder 10 can be increased, thereby improving the thermal insulation effect of the liquid nitrogen refrigeration device 100.

[0074] For some examples, see Figure 1 , Figure 2 and Figure 4 Part of the exhaust tube 30 is located in the vacuum chamber 10a, and the other part of the exhaust tube 30 is located outside the vacuum chamber 10a. The exhaust tube 30 forms an exhaust chamber 30c. The portion of the exhaust tube 30 located in the vacuum chamber 10a forms a flow hole 30a, and the flow hole 30a connects the exhaust chamber 30c and the vacuum chamber 10a. The portion of the exhaust tube 30 located outside the vacuum chamber 10a forms an outlet 30b, and the outlet 30b is connected to the exhaust chamber 30c.

[0075] The gas in the vacuum chamber 10a passes through the flow hole 30a and the exhaust chamber 30c, and then is discharged to the outside through the outlet 30b. Figure 4The gas outlet 30b is formed at the position where the exhaust pipe 30 is located outside the vacuum chamber 10a, so that the operator can easily set the vacuum equipment at the gas outlet 30b to exhaust the gas in the vacuum chamber 10a, and the operation is convenient.

[0076] Illustratively, during the assembly process of the outer tube 10 and the exhaust tube 30, the connecting piece 12 can be first welded to the exhaust tube 30 to ensure that the flow hole 30a and the air outlet 30b are respectively located on opposite sides of the connecting piece 12, that is, the flow hole 30a is located at the part where the exhaust tube 30 extends into the vacuum chamber 10a, and the air outlet 30b is located at the part of the exhaust tube 30 outside the vacuum chamber 10a, and then the connecting piece 12 is connected to the outer tube body 11, thereby improving the product quality of the liquid nitrogen refrigeration device 100.

[0077] For some examples, see Figure 2 The liquid nitrogen refrigeration device 100 includes a connecting flange 50, and there are multiple gas outlets 30b. A connecting flange 50 is arranged on the outer side of at least one gas outlet 30b, and the connecting flange 50 is communicated with the corresponding gas outlet 30b.

[0078] The plurality of gas outlets 30b can increase the exhaust speed of the gas in the vacuum chamber 10a and improve the working efficiency. The connecting flange 50 can be used to connect the vacuum pumping pipe externally, and then connected to the vacuum pumping equipment through the vacuum pumping pipe, so that the air flow can be discharged from the exhaust chamber 30c through the gas outlet 30b, and the connection stability between the vacuum pumping equipment and the exhaust pipe 30 can also be enhanced.

[0079] A pipe flange 50 is disposed outside the air outlet 30b, that is, the pipe flange 50 is disposed outside the side wall of the exhaust pipe 30, does not occupy the space of the exhaust cavity 30c, and is also convenient for operators to assemble the exhaust pipe 30 and the pipe flange 50. For example, please refer to Figure 1 The connecting flange 50 extends along the first direction, so that the connecting flange 50 has a guiding effect on the gas, so that the gas flow can flow smoothly. The first direction is perpendicular to the up-down direction.

[0080] It should be noted that, in the present application, down refers to the direction toward the ground, and up refers to the direction opposite to down.

[0081] In one embodiment, there are multiple connecting flanges 50, see Figure 2 Each gas outlet 30b is provided with a corresponding connecting flange 50.

[0082] For some examples, see Figure 1 The liquid nitrogen refrigeration device 100 includes an inner tube 60, an air inlet pipe 70 and an air outlet pipe 80. The inner tube 60 is located in the liquid storage chamber 20a. The inner tube 60 forms an air storage chamber 60a. The air inlet pipe 70 and the air outlet pipe 80 are both connected to the air storage chamber 60a.

[0083] The gas storage chamber 60a is used to store the raw gas. The inner layer cylinder 60 is located in the liquid storage chamber 20a, and the liquid nitrogen can absorb the heat in the raw gas, thereby realizing the refrigeration of the raw gas. For example, the raw gas flows into the gas storage chamber 60a through the air inlet pipe 70, and the raw gas is discharged through the air outlet pipe 80 after the raw gas is cooled and cooled in the gas storage chamber 60a. This cycle is repeated to continuously refrigerate the raw gas.

[0084] In one embodiment, please refer to Figure 1 The inner tube 60 includes an inner head 61 and an inner tube body 62. The inner head 61 is arranged at one end of the inner tube along the axial direction and is welded to the inner tube body 62. In this way, the connection stability between the inner head 61 and the inner tube body 62 can be enhanced, and at the same time, the sealing performance of the air storage chamber 60a can be improved to ensure the reliability of the sealing. In addition, the inner head 61 and the inner tube body 62 can be designed and produced separately, reducing the difficulty of manufacturing the inner tube 60.

[0085] The specific materials of the inner head 61 and the inner cylinder 62 are not limited. For example, the inner head 61 and the inner cylinder 62 can both be made of S30408 ​​stainless steel, which has a good heat insulation effect.

[0086] In one embodiment, the thickness of the inner cylinder 62 is 7 mm to 10 mm. For example, the thickness of the inner cylinder 62 can be 7 mm, 8 mm, 9 mm or 10 mm, etc.

[0087] For some examples, see Figure 1 , the diameter of the air inlet pipe 70 is greater than the diameter of the air outlet pipe 80 .

[0088] It can be understood that the temperature of liquid nitrogen is between -196°C (degrees Celsius) and -210°C, and the temperature inside the liquid storage chamber 20a and its surrounding areas is very low. By expanding the diameter of the intake pipe 70, it is possible to prevent the water vapor entrained in the raw gas from freezing and blocking the intake pipe 70 during the flow of the raw gas in the intake pipe 70, so that the raw gas can flow more smoothly in the intake pipe 70.

[0089] For some examples, see Figure 1 The inner tube 60 and the middle tube 20 are both located above the exhaust tube 30, the air inlet pipe 70 includes a first communication port 70a communicating with the air storage chamber 60a, the air outlet pipe 80 includes a second communication port 80a communicating with the air storage chamber 60a, and the height of the first communication port 70a is lower than the height of the second communication port 80a. In this way, the exhaust tube 30 plays a certain supporting role on the inner tube 60 and the middle tube 20, which can improve the stability of the inner tube 60 and the middle tube 20.

[0090] Please continue reading Figure 1The height of the first connecting port 70a is lower than the height of the second connecting port 80a, that is, in the up and down directions, the first connecting port 70a and the second connecting port 80a are spaced apart, so that the flow path of the raw gas in the gas storage chamber 60a can be extended, so that the liquid nitrogen can fully refrigerate the raw gas, thereby improving the refrigeration effect of the liquid nitrogen refrigeration device 100.

[0091] For example, see Figure 1 and Figure 5 The first communication port 70a is located in the gas storage cavity 60a, the inner seal 61 is formed with a flow port 61a communicating with the gas storage cavity 60a, the gas outlet pipe 80 is connected to the inner seal 61, and the second communication port 80a is communicated with the flow port 61a. In other words, the gas inlet pipe 70 is passed through the inner seal 61 and extends into the gas storage cavity 60a, and the gas outlet pipe 80 does not extend into the gas storage cavity 60a. In this way, on the basis of being able to fully refrigerate the raw gas, it is prevented that the raw gas is collected at the inner seal 61 and its surrounding parts are difficult to discharge.

[0092] For some examples, see Figure 1 The middle tube 20 includes two middle heads 21 and a middle tube body 22. The two middle heads 21 are respectively arranged at the two ends of the middle tube body 22 in the axial direction and are welded to the middle tube body 22. In this way, the connection stability between the middle heads 21 and the middle tube body 22 can be enhanced, and at the same time, the sealing performance of the liquid storage chamber 20a can be improved to ensure the reliability of the sealing. In addition, the middle heads 21 and the middle tube body 22 can be designed and produced separately, reducing the manufacturing difficulty of the middle tube 20.

[0093] The specific materials of the middle head 21 and the middle cylinder 22 are not limited. For example, the middle head 21 and the middle cylinder 22 can both be made of S30408 ​​stainless steel, which has a good heat insulation effect.

[0094] In one embodiment, the thickness of the middle cylinder 22 is 4 mm to 8 mm. For example, the thickness of the middle cylinder 22 can be 4 mm, 5 mm, 6 mm, 7 mm or 8 mm, etc.

[0095] For some examples, see Figure 1 The exhaust pipe 30 includes two first end caps 31 and a first cylinder 32. The two first end caps 31 are respectively arranged at both ends of the first cylinder 32 along the axial direction and are welded to the first cylinder 32. In this way, the connection stability between the first end caps 31 and the first cylinder 32 can be enhanced, and at the same time, the sealing performance of the exhaust cavity 30c can be improved to ensure the reliability of the sealing. In addition, the first end caps 31 and the first cylinder 32 can be designed and produced separately, reducing the manufacturing difficulty of the exhaust pipe 30.

[0096] The specific materials of the first end cap 31 and the first cylinder 32 are not limited. For example, the first end cap 31 and the first cylinder 32 can both be made of S30408 ​​stainless steel, which has a good heat insulation effect.

[0097] In one embodiment, the thickness of the first cylinder 32 is 4 mm to 8 mm. For example, the thickness of the first cylinder 32 can be 4 mm, 5 mm, 6 mm, 7 mm or 8 mm, etc.

[0098] In one embodiment, please refer to Figure 1 The middle head 21 and the first head 31 are both plate-shaped. That is to say, the surfaces of the middle head 21 and the first head 31 are both flat, so that the middle head 21 and the first head 31 are relatively flat, which is not only convenient for connection with the fastening structure 42, but also convenient for setting other components such as temperature detectors.

[0099] For some examples, see Figure 1 The liquid nitrogen refrigeration device 100 includes a support flange 90, which is disposed on a side of the connection member 12 away from the vacuum chamber 10a. The support flange 90 is formed with a fixing hole 90a, and the hole wall surface of the fixing hole 90a is welded to the outer wall surface of the exhaust pipe 30. In other words, the support flange 90 is located outside the vacuum chamber 10a. The support flange 90 plays a supporting and reinforcing role, which can improve the stability of the liquid nitrogen refrigeration device 100.

[0100] In one embodiment, the liquid nitrogen refrigeration device 100 provided by the present application is used to refrigerate CO, wherein the thickness of the outer cylinder 11 is 5 mm, the thickness of the middle cylinder 22 and the first cylinder 32 are both 4 mm, and the thickness of the inner cylinder 62 is 7 mm. During the refrigeration process of CO, no ice or frost appears on the surfaces of the structural parts such as the outer cylinder 10, the exhaust cylinder 30 and the middle cylinder 20, and no ice blockage occurs in the air inlet pipe 70, and the liquid nitrogen refrigeration device 100 has a better heat insulation effect.

[0101] For some examples, see Figure 1 and Figure 6The air inlet pipe 70 includes a first air inlet section 71, a second air inlet section 72 and a third air inlet section 73 which are connected in sequence. The first air inlet section 71 is provided through the support flange 90 and the connection flange and extends in the up-down direction until the highest point of the first air inlet section 71 is higher than the middle end cap 21. The third air inlet section 73 is provided through the middle end cap 21 and the inner end cap 61 and extends into the air storage cavity 60a. The highest point of the third air inlet section 73 is higher than the middle end cap 21. The opposite ends of the second air inlet section 72 are connected to the highest point of the first air inlet section 71 and the highest point of the third air inlet section 73 respectively. In other words, the second air inlet section 72 is higher than the middle cylinder 20, and the raw gas flows into the outlet cavity through the first air inlet section 71, the second air inlet section 72 and the third air inlet section 73 in sequence, which can reduce the phenomenon of reflux of the raw gas in the flow process of the air inlet pipe 70.

[0102] The highest point of the first air inlet section 71 and the highest point of the third air inlet section 73 may be flush, that is, the second air inlet section 72 extends substantially along the first direction.

[0103] See also Figure 6 The first air inlet section 71, the second air inlet section 72 and the third air inlet section 73 are generally in an inverted U shape, and the structure is compact. In addition, the length of the air inlet pipe 70 can be increased as much as possible in a relatively small space, and the flow time of the raw gas in the air inlet pipe 70 is prolonged. Therefore, the retention time of the raw gas in the gas storage cavity 60a is prolonged, so that the liquid nitrogen refrigeration device 100 can fully refrigerate the raw gas in the gas storage cavity 60a.

[0104] For some examples, see Figure 1 and Figure 7 The gas outlet pipe 80 includes a first gas outlet section 81, a second gas outlet section 82 and a third gas outlet section 83 which are connected in sequence. The first gas outlet section 81 is arranged through the middle end cap 21 and the inner end cap 61 and extends in the up-down direction. The highest point of the first gas outlet section 81 is higher than the middle end cap 21. The third gas outlet section 83 extends in the up-down direction and is arranged through the connecting flange and the supporting flange 90. The highest point of the third gas outlet section 83 is higher than the middle end cap 21. The opposite ends of the second gas outlet section 82 are respectively connected with the highest point of the first gas outlet section 81 and the highest point of the third gas outlet section 83. In other words, the second gas outlet section 82 is higher than the middle cylinder 20, and the raw gas is discharged outward through the first gas outlet section 81, the second gas outlet section 82 and the third gas outlet section 83 in sequence, which can reduce the phenomenon of reflux of the raw gas in the flow process of the gas outlet pipe 80.

[0105] The highest point of the first air outlet section 81 and the highest point of the third air outlet section 83 may be flush, that is, the second air outlet section 82 extends substantially along the first direction.

[0106] See also Figure 7The first gas outlet section 81, the second gas outlet section 82 and the third gas outlet section 83 are substantially in an inverted L shape, and the structure is compact. In addition, the length of the gas outlet pipe 80 can be increased as much as possible in a relatively narrow space, that is, the capacity of the gas outlet pipe 80 is increased, so that the refrigerated raw gas can be discharged relatively smoothly through the gas outlet pipe 80.

[0107] In the description of this specification, the description with reference to the terms "an embodiment", "some embodiments" and "exemplary" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0108] The various embodiments / implementations provided in this application can be combined with each other without causing any contradiction. The above description is only a preferred embodiment of this application and is not intended to limit this application. For those skilled in the art, this application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. A liquid nitrogen refrigeration device, characterized in that: include: An outer tube is formed with a vacuum cavity; A middle cylinder is arranged in the vacuum chamber, and the middle cylinder is formed with a liquid storage chamber, and the liquid storage chamber is used to store liquid nitrogen; An exhaust cylinder, part of which is located in the vacuum chamber, and the exhaust cylinder is in communication with the vacuum chamber to exhaust the gas in the vacuum chamber; The heat insulation device is arranged between the middle tube and the exhaust tube.

2. The liquid nitrogen refrigeration device according to claim 1, characterized in that: The heat insulation device includes a heat insulation board and a plurality of fastening structures. The heat insulation board is arranged between the middle tube and the exhaust tube at intervals. Some of the fastening structures connect the heat insulation board and the middle tube, and other parts of the fastening structures connect the heat insulation board and the exhaust tube.

3. The liquid nitrogen refrigeration device according to claim 2, characterized in that: The heat insulation board forms a limiting hole, and the fastening structure includes a main body and two adjusting parts. The middle tube and the exhaust tube are both connected to the corresponding main body. The main body is penetrated by the limiting hole and the two adjusting parts. The two adjusting parts are respectively located on both sides of the heat insulation board along the thickness direction. The two adjusting parts are used to lock or unlock the main body, wherein the hole wall surface of the limiting hole and the circumferential surface of the main body are spaced apart.

4. The liquid nitrogen refrigeration device according to claim 3, characterized in that: The fastening structure comprises a plurality of heat-insulating washers, each of the adjusting members corresponds to a heat-insulating washers, and the heat-insulating washers are clamped between the adjusting members and the heat-insulating plates.

5. The liquid nitrogen refrigeration device according to claim 1, characterized in that: The outer layer tube includes an outer tube body and a connecting piece, wherein one end of the outer tube body along the axial direction has an opening, and the connecting piece closes the axial opening of the outer tube body, and the connecting piece forms a positioning hole connected to the vacuum chamber, and the hole wall of the positioning hole is sealed and connected to the outer wall of the exhaust tube.

6. The liquid nitrogen refrigeration device according to claim 1, characterized in that: Part of the exhaust tube is located in the vacuum chamber, and the other part of the exhaust tube is located outside the vacuum chamber. The exhaust tube forms an exhaust chamber, and the portion of the exhaust tube located in the vacuum chamber forms a flow hole, and the flow hole connects the exhaust chamber and the vacuum chamber. The portion of the exhaust tube located outside the vacuum chamber forms an air outlet, and the air outlet is connected to the exhaust chamber.

7. The liquid nitrogen refrigeration device according to claim 6, characterized in that: The liquid nitrogen refrigeration device comprises a connecting flange, and there are multiple gas outlets. The connecting flange is arranged on the outer side of at least one gas outlet, and the connecting flange is communicated with the corresponding gas outlet.

8. The liquid nitrogen refrigeration device according to any one of claims 1 to 7, characterized in that: The liquid nitrogen refrigeration device comprises an inner layer cylinder, an air inlet pipe and an air outlet pipe, wherein the inner layer cylinder is located in the liquid storage cavity, the inner layer cylinder forms an air storage cavity, and the air inlet pipe and the air outlet pipe are both connected to the air storage cavity.

9. The liquid nitrogen refrigeration device according to claim 8, characterized in that: The diameter of the air inlet pipe is greater than the diameter of the air outlet pipe.

10. The liquid nitrogen refrigeration device according to claim 8, characterized in that: The inner tube and the middle tube are both located above the exhaust tube, the air inlet pipe includes a first connecting port connected to the air storage chamber, the air outlet pipe includes a second connecting port connected to the air storage chamber, and the height of the first connecting port is lower than that of the second connecting port.

Images