CN116313372B - Superconducting magnet and cooling system and method thereof - Google Patents

Abstract

The application discloses a superconducting magnet and a cooling system and method thereof, relates to the technical field of superconducting magnets, and solves the problem that the cooling capacity of a second-stage cold head is small and the superconducting coil cannot be cooled rapidly; the cooling system comprises a refrigerator, a second container, a cold screen and a first container, wherein the second container, the cold screen and the first container are sleeved in sequence from outside to inside, the first container is used for setting a superconducting coil, a sealed first interlayer is formed between the first container and the cold screen, a sealed second interlayer is formed between the cold screen and the second container, the first interlayer is not communicated with the second interlayer, the second interlayer forms vacuum, the first interlayer is provided with a convection heat exchange medium, and the first-stage cold head is used for cooling the superconducting coil in a convection heat exchange mode by utilizing the convection heat exchange medium to enable the cold screen and the first container. The cooling system of the superconducting magnet can accelerate the cooling process of the superconducting coil by utilizing the cooling capacity of the first-stage cold head and the convection heat exchange medium.

Description

Superconducting magnet and cooling system and method thereof

Technical Field

The application relates to the technical field of superconducting magnets, in particular to a superconducting magnet and a cooling system and a cooling method thereof.

Background

The superconducting magnet is an electromagnet with a coil made of a second type of superconductor having a high transition temperature and a particularly high critical magnetic field at a low temperature, and is composed of a low-temperature container, a cold shield, and a vacuum container sequentially sleeved.

The vacuum layer between the 300K cold screen and the 50K cold screen and the vacuum layer between the 50K cold screen and the 4K container are communicated, namely, a vacuum device is connected to a vacuum pumping port of the 300K container, and the interlayer can be wholly vacuumized, so that the high vacuum of the superconducting magnet is realized, and the aim of reducing the heat leakage of the magnet is fulfilled.

In the cooling mode of the superconducting magnet, the first stage of the cold head of the refrigerator cools the 50K cold screen, and the second stage of the cold head is used for realizing zero volatilization of liquid helium in the 4K container or cooling and cooling of the magnet coil. In the cooling process of the 4K container and the superconducting coil, if no auxiliary means are provided, the cooling efficiency is lower only by the cold head secondary to cool the 4K container and the superconducting coil, especially when the 4K container and the superconducting coil are in a higher temperature region, such as 80K-300K, the total heat mass of the 4K container and the superconducting coil is larger, and meanwhile, the refrigerating capacity of the cold head secondary is smaller, so that the purpose of high-efficiency cooling is difficult to realize. Therefore, in the interval from 300K to 80K, the common cooling mode is to cool the nitrogen in the 4K container by transfusion or cool the nitrogen by an auxiliary refrigerator tool, and the required materials and equipment have high cost.

Disclosure of Invention

The application aims to provide a cooling system of a superconducting magnet, which can accelerate the cooling process of a superconducting coil by utilizing the cooling capacity of a first-stage cold head and a convection heat exchange medium, and solves the problem that the cooling capacity of a second-stage cold head is smaller and the superconducting coil cannot be cooled rapidly. Another object of the present application is to provide a cooling method of a superconducting magnet applied to a cooling system, and a superconducting magnet including the cooling system.

In order to achieve the above purpose, the application provides a cooling system of a superconducting magnet, which comprises a refrigerator, a second container, a cold screen and a first container, wherein the second container, the cold screen and the first container are sleeved in sequence from outside to inside, the inside of the first container is used for arranging a superconducting coil, a sealed first interlayer is formed between the outside of the first container and the inside of the cold screen, a sealed second interlayer is formed between the outside of the cold screen and the inside of the second container, a first-stage cold head of the refrigerator is used for cooling the cold screen, a second-stage cold head of the refrigerator is used for cooling the superconducting coil, the first interlayer is not communicated with the second interlayer, the second interlayer forms vacuum, the first interlayer is provided with a convection heat exchange medium, and the cooling of the superconducting coil by the cold screen and the first container is realized in a convection heat exchange mode by utilizing the convection heat exchange medium.

In some embodiments, the first interlayer and the second interlayer have separate air interfaces through which the second interlayer forms a vacuum, and the first interlayer is charged with convective heat transfer medium through the air interfaces.

In some embodiments, the first interlayer is a permanent, fixed seal and the convective heat transfer medium of the first interlayer is neon.

In some embodiments, the refrigerator is disposed in the second container, the refrigerator further comprises a cooling base, the first stage cold head is disposed in the cooling base, and the cooling base is thermally connected with the cold screen.

In some embodiments, the second stage coldhead is located inside the first vessel and the second stage coldhead is thermally coupled to the superconducting coil.

In some embodiments, a pull rod mechanism is also included, the pull rod mechanism being coupled to the first container and the second container, the pull rod mechanism being configured to support the first container.

In some embodiments, the pull rod mechanism comprises a pull rod, a mounting assembly, an adjusting assembly and a corrugated pipe, wherein the mounting assembly is arranged on the cold screen, the adjusting assembly is connected with the corrugated pipe between the mounting assembly, the pull rod is positioned inside the mounting assembly, the adjusting assembly and the corrugated pipe, a first fixed end of the pull rod penetrates through the cold screen and is connected with the first container, and a second fixed end of the pull rod is connected with the adjusting assembly.

In some embodiments, the mounting assembly includes a cold screen connection flange, a first connection block, and a first fixing base, where the cold screen connection flange, the first connection block, and the first fixing base are provided with holes for accommodating the tie rods, the cold screen connection flange is connected with the cold screen, the first connection block is connected with the cold screen connection flange, and the first fixing base is connected with the first connection block; the adjusting assembly comprises a second fixed base and a second connecting block, holes for accommodating the pull rods are formed in the second fixed base and the second connecting block, the second fixed base is connected with the second container, and the second connecting block is connected with the second fixed base; the first fixed end of the pull rod is in threaded connection with the first container, and the second fixed end of the pull rod is in threaded connection with the second connecting block.

The application also provides a cooling method of the superconducting magnet, which is applied to the cooling system and comprises the following steps:

the second interlayer forms vacuum, the first interlayer is provided with a convection heat exchange medium, the first-stage cold head refrigerates, the cold energy is conducted to the cold screen, and the convection heat exchange medium of the first interlayer enables the cold screen and the first container to realize the cooling of the first-stage cold head to the superconducting coil in a convection heat exchange mode.

The application also provides a superconducting magnet, which comprises the cooling system and further comprises a superconducting coil arranged inside the first container.

Compared with the background technology, the cooling system of the superconducting magnet provided by the application comprises a refrigerator, a second container, a cold screen and a first container, wherein the second container, the cold screen and the first container are sleeved in sequence from outside to inside, the superconducting coil is arranged in the first container, a sealed first interlayer is formed between the outer part of the first container and the inner part of the cold screen, a sealed second interlayer is formed between the outer part of the cold screen and the inner part of the second container, a first-stage cold head of the refrigerator is used for cooling the cold screen, a second-stage cold head of the refrigerator is used for cooling the superconducting coil, the first interlayer is not communicated with the second interlayer, the second interlayer forms vacuum, the first interlayer is provided with a convection heat exchange medium, and the cold screen and the first container realize cooling of the superconducting coil in a convection heat exchange mode by utilizing the convection heat exchange medium.

This cooling system carries out independent isolation design with first intermediate layer and second intermediate layer, the second intermediate layer forms the vacuum, first intermediate layer has convection heat transfer medium, utilize the cold volume of conduction to the cold screen that first stage cold head provided, and by means of the mode of convection heat transfer between cold screen and the first container that is realized by convection heat transfer medium, compare in the traditional mode that only second stage cold head carries out heat transfer with superconducting coil, this cooling system can accelerate superconducting coil's cooling process, with this has solved the problem that the cold volume of second stage cold head is less can not realize the quick cooling to superconducting coil.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present application, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic view of a cooling system for a superconducting magnet according to a first embodiment of the present application;

FIG. 2 is a schematic diagram of a cooling system for a superconducting magnet of the prior art;

FIG. 3 is a schematic view of the pull rod mechanism of FIG. 1;

fig. 4 is a schematic view of a cooling system for a superconducting magnet according to a second embodiment of the present application.

Wherein:

1-refrigerator, 2-second container, 3-second interlayer, 4-cold screen, 5-first interlayer, 6-first container 7-superconducting coils, 8-first air interfaces, 9-second air interfaces, 10-pull rod mechanisms, 11-thermal connection assemblies,

101-first stage coldhead, 102-second stage coldhead, 103-cooling base, 1001-tie rod, 1002-mounting assembly, 1003-conditioning assembly, 1004-bellows,

10011-first fixed end, 10012-second fixed end, 10021-cold screen connecting flange, 10022-first connecting block, 10023-first fixed base, 10031-second fixed base, 10032-second connecting block.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The present application will be further described in detail below with reference to the drawings and detailed description for the purpose of enabling those skilled in the art to better understand the aspects of the present application.

Referring to fig. 1 and 2, fig. 1 is a schematic diagram of a cooling system for a superconducting magnet according to a first embodiment of the present application, and fig. 2 is a schematic diagram of a cooling system for a superconducting magnet according to the prior art.

As shown in fig. 2, the conventional cooling system and the superconducting coil 7 constitute a conventional superconducting magnet structure, and the superconducting coil 7 is generally connected to the first container 6 as a whole through structural design and welding processes. A first interlayer 5 is formed between the first container 6 and the cold screen 4, a second interlayer 3 is formed between the cold screen 4 and the second container 2, and the first interlayer 5 and the second interlayer 3 are communicated through openings in the cold screen 4. When the vacuum device connected to the vacuum port communicated with the second interlayer 3 is connected to vacuum the second interlayer 3, the first interlayer 5 is also vacuumized because the first interlayer 5 is communicated with the second interlayer 3, and when the vacuum is finished, the first interlayer 5 and the second interlayer 3 simultaneously establish high vacuum.

With continued reference to fig. 2, the first stage cold head 101 is fixed on the cooling base 103, the cold of the first stage cold head 101 is conducted to the cooling base 103, and then is conducted to the cold screen 4 through thermal connection, the first stage cold head 101 directly achieves cooling of the cold screen 4, and the second stage cold head 102 directly achieves cooling of the first container 6 and the superconducting coil 7 therein.

The parts of the cooling system are associated with temperature correspondence, for example a 4K cold head, a 4K container for the first container 6, a 50K cold screen for the cold screen 4 and a 300K container for the second container 2. In combination with the above description of the technical solution, the existing cooling system has the disadvantage that the cooling capacity of the second-stage cold head 102 is small, and rapid cooling of the first container 6 and the superconducting coil 7 therein cannot be achieved. In particular, for the liquid helium zero-volatilization system, the heat exchange is carried out between the second-stage cold head 102 and the superconducting coil 7 in a convection mode, so that the liquid helium zero-volatilization system is suitable for the steady state of a zero-volatilization magnet, but the unsteady state cooling of the superconducting coil 7 from 300K to 4K is difficult to realize in the mode, and the liquid helium zero-volatilization system can only be realized through auxiliary cooling means, such as nitrogen filling in the first container 6 or installing a cold head special for high-power cooling. For example, when the superconducting magnet fails, especially at the client, the 4K container and the superconducting coil 7 are heated to a higher temperature, for example, to 300K, due to long-time power failure or quench, so that only liquid nitrogen or a cold head for auxiliary cooling is used, and the required materials and equipment are high in cost.

Aiming at the defects of the existing cooling system, the application provides a cooling system of a superconducting magnet, which aims to solve the problem that the cooling capacity of a second-stage cold head 102 is small and the rapid cooling of a superconducting coil 7 can not be realized, and realize the efficient cooling of a first container 6 and the superconducting coil 7.

As shown in fig. 1, the cooling system (cooling system for short) of the superconducting magnet provided by the application mainly comprises a refrigerator 1, a second container 2, a cold screen 4 and a first container 6.

The second container 2, the cold screen 4 and the first container 6 are sleeved in sequence from outside to inside, the inside of the first container 6 is used for arranging the superconducting coil 7, a sealed first interlayer 5 is formed between the outside of the first container 6 and the inside of the cold screen 4, and a sealed second interlayer 3 is formed between the outside of the cold screen 4 and the inside of the second container 2. The first stage cold head 101 of the refrigerator 1 is used for cooling the cold screen 4 and the second stage cold head 102 of the refrigerator 1 is used for cooling the superconducting coil 7.

Comparing fig. 1 with fig. 2, it is found that the first interlayer 5 and the second interlayer 3 in fig. 1 are not communicated with each other, so as to enable the convective heat transfer medium only existing in the first interlayer 5 but not existing in the second interlayer 3 to be injected into the first interlayer 5, and the convective heat transfer medium is utilized to enable the cold shield 4 and the first container 6 to realize the cooling of the superconducting coil 7 by the first stage cold head 101 in a manner of convective heat transfer. At the same time, the second interlayer 3 forms a vacuum, guaranteeing the cooling effect inside the second interlayer 3.

Therefore, in combination with the above technical solution of the present application, the cooling system performs independent isolation design on the first interlayer 5 and the second interlayer 3, the second interlayer 3 forms vacuum, the first interlayer 5 has a convection heat exchange medium, and the cooling process of the superconducting coil 7 can be accelerated by using the cooling capacity of the first stage cold head 101, which is provided by the first stage cold head and is conducted to the cold screen 4, and by means of convection heat exchange between the cold screen 4 and the first container 6, which is realized by the convection heat exchange medium.

Compared with the existing cooling system, the cooling system not only reserves the traditional mode of heat exchange between the second-stage cold head 102 and the superconducting coil 7, but also increases a new mode of heat convection between the cold screen 4 and the first container 6, and makes up the defect of the cold quantity of the second-stage cold head 102, thereby solving the problem that the quick cooling of the superconducting coil 7 cannot be realized due to the small cold quantity of the second-stage cold head 102.

In a specific embodiment, the parts of the cooling system are associated with temperature, and the cold head of the refrigerator 1 is a 4K cold head, the first stage cold head 101 is a stage of the 4K cold head, the second stage cold head 102 is a second stage of the 4K cold head, the first container 6 is a 4K container, the cold screen 4 is a 50K cold screen, and the second container 2 is a 300K container. The cooling system is to cool the superconducting coil 7 by using the cooling capacity of the first stage of the 4K cold head.

In this embodiment, the vacuum interlayers of the two magnets, namely the first interlayer 5 and the second interlayer 3, are designed as independent structures, namely the first vacuum interlayer between the 4K container and the 50K cold screen and the second vacuum interlayer between the 300K container and the 50K cold screen are independent of each other.

When the cooling system is used for cooling the superconducting magnet, the second vacuum interlayer can be vacuumized and high vacuum is established, the first vacuum interlayer is vacuumized first, and then a proper amount of dry nitrogen (or other gases such as neon, hydrogen and the like) is filled, so that convection heat exchange can be formed between the 50K cold screen and the 4K container. When the 4K cold head first stage cools down for the 50K cold screen, because the effect of convection heat transfer, can indirectly cool down for 4K container and superconducting coil 7, just so can realize 4K container and superconducting coil 7's high-efficient cooling.

It should be noted that the core of this embodiment is to form convection heat exchange, but not to vacuum the convection heat exchange medium of the first interlayer 5 and the second interlayer 3, where the first interlayer 5 is loaded with the convection heat exchange medium in multiple ways, and the second interlayer 3 is also constructed in multiple ways to realize the vacuum environment, which shall fall within the scope of the description of this embodiment.

In a first way of loading the heat convection medium, the first interlayer 5 is provided with a first air port 8, and the first interlayer 5 is filled with and discharged from the heat convection medium through its first air port 8, the heat convection medium being not limited herein. Before the convective heat transfer medium is filled, the first interlayer 5 needs to be cleaned and replaced through the first air interface 8, and a vacuumizing-nitrogen replacement-vacuumizing process is adopted.

In a second way of loading the convective heat transfer medium, the convective heat transfer medium of the first interlayer 5 may be permanently retained for certain specific conditions, so that the first interlayer 5 is permanently fixed sealed.

In this embodiment, in the case where the convective heat transfer medium of the first interlayer 5 is permanently left, the convective heat transfer medium of the first interlayer 5 is neon. The normal boiling point of neon is 27K, that is, a proper amount of neon (0-1 atm), and is always in a gaseous state when the temperature of the first interlayer 5 is higher than 27K.

Taking neon permanently sealed in the first interlayer 5 as an example, when the first container 6 (4K container) and the superconducting coil 7 continue to cool down to the temperature zone of 4K, neon is solidified, no convection heat exchange is generated, that is, when the first container 6 and the superconducting coil 7 are in the temperature zone of 4K in the normal working state, neon in the first interlayer 5 cannot cause increase of heat leakage; when the first container 6 and the superconducting coil 7 are re-warmed to a higher temperature region above 30K due to failure, such as 200K, neon in the first interlayer 5 is changed into a gas state again, and serves as a medium for convective heat transfer again, so that efficient cooling of the 4K container and the superconducting coil 7 is realized again.

In some embodiments, the second interlayer 3 is provided with a second air interface 9, irrespective of whether the convective heat transfer medium is permanently sealed, the second interlayer 3 creating a vacuum environment through its second air interface 9.

Illustratively, as shown in fig. 1, the first interlayer 5 and the second interlayer 3 each have an independent air interface, i.e., the first interlayer 5 has a first air interface 8 and the second interlayer 3 has a second air interface 9. The first interlayer 5 and the second interlayer 3 are non-permanent closed structures which can exchange gas from outside through the gas interface, namely, the first interlayer 5 can be vacuumized and vacuum sealed through the gas interface, and the second interlayer 3 can be vacuumized and vacuum sealed through the gas interface.

The cooling process of the cooling system is described below along with the corresponding relationship between the respective parts of the cooling system and the temperature.

When the cooling capacity of the first-stage cold head 101 (4K cold head one stage) is needed to cool the first container 6 (4K container) and the superconducting coil 7, high vacuum is established on the second interlayer 3 through the second air interface 9, then the vacuumizing-replacement-vacuumizing operation is performed on the first interlayer 5 through the first air interface 8, and then a proper amount of neon gas (the gas can be nitrogen gas or other gases according to the use condition) is filled into the first interlayer 5 through the first air interface 8 (auxiliary tools are installed in good time). The cold energy of the first-stage cold head 101 is conducted to the cold screen 4 (50K cold screen), because a proper amount of neon is filled between the cold screen 4 and the first container 6, the neon is used as a convection heat exchange medium, and the cold energy is transferred from the cold screen 4 to the first container 6 and the superconducting coil 7, so that the temperature of the superconducting coil 7 is reduced from 300K to 30K by the cold energy of the first-stage cold head 101. When the temperature of the superconducting coil 7 is reduced to be close to 30K, the first interlayer 5 can be vacuumized through the first air interface 8, neon is vacuumized, and high vacuum is established. High vacuum. Conversely, the neon in the first interlayer 5 may be permanently sealed in the first interlayer 5, and the principle and effect of the neon permanently sealed in the first interlayer 5 are described in the above description, which is not repeated herein.

With continued reference to fig. 1, as shown in fig. 1, the refrigerator 1 is disposed in the second container 2, and the refrigerator 1 further includes a cooling base 103.

In this embodiment, the cooling base 103 is provided with the first stage cold head 101, and the first stage cold head 101 is located on the cooling base 103, and the cooling base 103 is thermally connected with the cold screen 4, so that the cooling capacity of the first stage cold head 101 can be conducted to the cooling base 103, and the cooling base 103 conducts the cooling capacity to the 5 cold screen 4 through the thermal connection.

In addition, a second-stage coldhead 102 is located inside the first container 6, and the second-stage coldhead 102 transfers cooling energy to the superconducting coil 7.

With continued reference to fig. 1 and with further reference to fig. 4, fig. 4 is a schematic diagram of a cooling system for a superconducting magnet according to a second embodiment of the present application.

Comparing fig. 1 and fig. 4, it is found that the second stage coldhead 102 in fig. 1 is in convective heat transfer with the superconducting coil 7, while the second stage coldhead 102 in fig. 4 is thermally connected with the superconducting coil 7 by a thermal connection assembly 11. Thus, according to the different variations of fig. 1 and 4, the cooling system is applicable to both liquid helium magnets and conductive cold non-liquid helium magnets after corresponding variations.

Referring to fig. 3, fig. 3 is a schematic view of the pull rod mechanism in fig. 1.

In some embodiments, the cooling system further comprises a pull rod mechanism 10, the pull rod mechanism 10 being connected to the first container 6 and the second container 2, the pull rod mechanism 10 being for supporting the first container 6.

In this embodiment, based on the above-mentioned technical solution that the first interlayer 5 and the second interlayer 3 are no longer in communication with each other, in order to achieve independent sealing between the first interlayer 5 and the second interlayer 3, a pull rod mechanism 10 with a special structure needs to be designed, as shown in fig. 3.

In some embodiments, the tie rod mechanism 10 includes a tie rod 1001, a mounting assembly 1002, an adjustment assembly 1003, and a bellows 1004.

In this embodiment, the installation component 1002 is disposed on the cold screen 4, the bellows 1004 is connected between the adjustment component 1003 and the installation component 1002, the pull rod 1001 is located inside the installation component 1002, the adjustment component 1003 and the bellows 1004, the first fixed end 10011 of the pull rod 1001 passes through the cold screen 4 and is connected to the first container 6, and the second fixed end 10012 of the pull rod 1001 is connected to the adjustment component 1003. The pull rod mechanism 10 can support the first container 6 and simultaneously ensure independent sealing between the first interlayer 5 and the second interlayer 3 which are respectively positioned on the inner side and the outer side of the cold screen 4.

In some embodiments, the mounting assembly 1002 includes a cold screen connection flange 10021, a first connection block 10022, and a first stationary base 10023, the cold screen connection flange 10021, the first connection block 10022, and the first stationary base 10023 are provided with holes for receiving the tie rods 1001, the cold screen connection flange 10021 is connected to the cold screen 4, the first connection block 10022 is connected to the cold screen connection flange 10021, and the first stationary base 10023 is connected to the first connection block 10022; the adjusting assembly 1003 includes a second fixed base 10031 and a second connection block 10032, the second fixed base 10031 and the second connection block 10032 are provided with holes for accommodating the pull rod 1001, the second fixed base 10031 is connected with the second container 2, the second connection block 10032 is connected with the second fixed base 10031, and the bellows 1004 is connected between the first fixed base 10023 and the second fixed base 10031; the first fixed end 10011 of the tie rod 1001 is screwed to the first container 6, and the second fixed end 10012 of the tie rod 1001 is screwed to the second connection block 10032.

In this embodiment, the first fixing end 10011 is provided with an external thread, and is fixed to the first container 6 in a threaded manner. The first fixing end 10011 and the second fixing end 10012 are integrally cured with the body of the tie rod 1001 by resin. The second fixed end 10012 is provided with external threads, the second connecting block 10032 is provided with internal threads, and the second connecting block 10032 is arranged on the second fixed end 10012 through a threaded connecting sleeve, so before the second connecting block 10032 is connected with the second fixed base 10031, the second connecting block 10032 can be screwed or loosened by external force to adjust the stress of the pull rod 1001 so as to meet the use requirement. The connection of the second connection block 10032 to the second stationary base 10031 is the last step in the installation process of the pull rod mechanism 10.

Illustratively, the first fixing base 10023 and the second fixing base 10031 are taken as metal bases for illustration, and the materials of the pull rod 1001, the first connecting block 10022, the first fixing base 10023, the second fixing base 10031 and the second connecting block 10032 are all stainless steel. All joints of the pull rod mechanism 10 require a welding process involving the entire cold screen 4, the transitional connection of the cold screen 4 to the pull rod mechanism 10, thereby forming a closed system between the cold screen 4 and the first container 6. The cold shield connecting flange 10021 is made of aluminum alloy, and is welded on the cold shield 4, and the cold shield connecting flange 10021 and the first connecting block 10022 are formed into a whole through friction welding. The first connecting block 10022 and the first fixing base 10023 are made of stainless steel, and are connected by welding. Bellows 1004 is welded at a first end to first mounting base 10023 and at a second end to second mounting base 10031, and bellows 1004 requires a certain amount of compressive deformation margin. The second fixing base 10031 and the second connecting block 10032 are made of stainless steel, and are connected by welding. It should be noted that, the first fixing base 10023, the bellows 1004, and the second fixing base 10031 are welded in advance to form a whole, and the second fixing base 10031 and the second connecting block 10032 are welded in a backward direction to form a whole. In the assembly process, the welding between the second fixing base 10031 and the second connecting block 10032 is the last welding process of the pull rod mechanism 10 in the installation process, so that the installation efficiency and reliability can be improved.

The application also provides a cooling method of the superconducting magnet, which is applied to the cooling system and comprises the following steps: vacuum is formed in the second interlayer 3, a convection heat exchange medium is arranged in the first interlayer 5, the first-stage cold head 101 refrigerates, cold energy is conducted to the cold screen 4, and the convection heat exchange medium of the first interlayer 5 enables the cold screen 4 and the first container 6 to realize cooling of the superconducting coil 7 by the first-stage cold head 101 in a convection heat exchange mode.

It should be noted that the core of the cooling method is that the vacuum interlayer based on the cooling system is designed in an independent split type, and the cooling process of the superconducting coil 7 can be accelerated by filling a proper amount of gas into the first interlayer 5 to serve as a thermal switch; as for the heat convection medium of the first interlayer 5 and the vacuum of the second interlayer 3, various manners are realized, and reference may be made to the above description, and the details are not repeated here.

The application also provides a superconducting magnet comprising the cooling system described above, and further comprising a superconducting coil 7 arranged inside the first container 6. The superconducting magnet should have all the advantages of the above-described cooling system, and will not be described in detail here. The application of the magnet is not limited herein, and the magnet can be used for manufacturing practical devices such as a nuclear magnetic resonance imaging superconducting magnet, a magnetic ore dressing superconducting magnet, a sewage treatment superconducting magnet, a superconducting energy storage device and the like, and the magnet belongs to the description range of the embodiment.

It should be noted that many components mentioned in the present application are common standard components or components known to those skilled in the art, and the structures and principles thereof are known to those skilled in the art through technical manuals or through routine experimental methods.

It should be noted that in this specification relational terms such as first and second are used solely to distinguish one entity from another entity without necessarily requiring or implying any actual such relationship or order between such entities.

The superconducting magnet and the cooling system and method thereof provided by the present application are described in detail above. The principles and embodiments of the present application have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present application and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the application can be made without departing from the principles of the application and these modifications and adaptations are intended to be within the scope of the application as defined in the following claims.

Claims (10)

1. The cooling system of the superconducting magnet comprises a refrigerator, a second container, a cold screen and a first container which are sleeved in sequence from outside to inside, wherein the first container is internally provided with a superconducting coil, a sealed first interlayer is formed between the outside of the first container and the inside of the cold screen, a sealed second interlayer is formed between the outside of the cold screen and the inside of the second container, a first-stage cold head of the refrigerator is used for cooling the cold screen, and a second-stage cold head of the refrigerator is used for cooling the superconducting coil, and the cooling system is characterized in that the first interlayer is not communicated with the second interlayer, the second interlayer forms vacuum, the first interlayer is provided with a convection heat exchange medium, and the cold screen and the first container realize cooling of the superconducting coil in a convection heat exchange mode by utilizing the convection heat exchange medium; the second-stage cold head is thermally connected with the superconducting coil through a thermal connection assembly.

2. The cooling system of claim 1, wherein the first interlayer and the second interlayer have separate air interfaces through which the second interlayer forms a vacuum, and the first interlayer is filled with convective heat transfer medium through the air interfaces.

3. The cooling system of claim 1, wherein the first interlayer is a permanent, fixed seal and the convective heat transfer medium of the first interlayer is neon.

4. The cooling system of claim 1, wherein the refrigerator is disposed in the second container, the refrigerator further comprising a cooling base, the first stage coldhead being disposed in the cooling base, the cooling base being thermally coupled to the cold screen.

5. The cooling system of claim 4, wherein the second stage coldhead is located inside the first vessel and the second stage coldhead is thermally coupled to the superconducting coil.

6. The cooling system of claim 1, further comprising a pull rod mechanism coupled to the first container and the second container, the pull rod mechanism for supporting the first container.

7. The cooling system of claim 6, wherein the pull rod mechanism comprises a pull rod, a mounting assembly, an adjusting assembly and a corrugated pipe, the mounting assembly is arranged at the cold screen, the adjusting assembly and the mounting assembly are connected with the corrugated pipe, the pull rod is positioned inside the mounting assembly, the adjusting assembly and the corrugated pipe, a first fixed end of the pull rod penetrates through the cold screen and is connected with the first container, and a second fixed end of the pull rod is connected with the adjusting assembly.

8. The cooling system of claim 7, wherein the mounting assembly comprises a cold screen connection flange, a first connection block, and a first stationary base, the cold screen connection flange, the first connection block, and the first stationary base defining a hole for receiving the tie rod, the cold screen connection flange being connected to the cold screen, the first connection block being connected to the cold screen connection flange, the first stationary base being connected to the first connection block; the adjusting assembly comprises a second fixed base and a second connecting block, holes for accommodating the pull rods are formed in the second fixed base and the second connecting block, the second fixed base is connected with the second container, and the second connecting block is connected with the second fixed base; the first fixed end of the pull rod is in threaded connection with the first container, and the second fixed end of the pull rod is in threaded connection with the second connecting block.

9. A cooling method of a superconducting magnet, applied to the cooling system according to any one of claims 1 to 8, comprising:

the second interlayer forms vacuum, the first interlayer is provided with a convection heat exchange medium, the first-stage cold head refrigerates, the cold energy is conducted to the cold screen, and the convection heat exchange medium of the first interlayer enables the cold screen and the first container to realize the cooling of the first-stage cold head to the superconducting coil in a convection heat exchange mode.

10. A superconducting magnet comprising the cooling system according to any one of claims 1 to 8, and further comprising a superconducting coil disposed inside the first container.