A liquid helium storage tank

Abstract

The present invention discloses a liquid helium storage tank, belonging to the field of liquid helium storage technology. The liquid helium storage tank comprises an outer shell, a cold shield, and an inner container, arranged sequentially from the outside to the inside. The cold shield is wrapped around the inner container, and the outer shell is wrapped around the cold shield, forming a three-layer straight cylindrical horizontal structure. The liquid helium storage tank uses the cold shield as a boundary and fulcrum to divide the tank support into two temperature ranges. The inner container is supported on the cold shield and the outer shell, and the cold shield is supported on the outer shell. The hot end temperature of the inner container support structure can be reduced from 293K to 77K, thereby significantly reducing radiative heat transfer. The liquid helium storage tank is also provided with a helium pipeline. When the helium pipeline is discharged, a shielding layer is formed outside the liquid helium pipeline to absorb external heat transfer, effectively reducing evaporation loss of liquid helium in the liquid helium pipeline. By providing a thermal bridge and a vacuum pipeline, a vacuum shielding layer is formed, thereby reducing the conduction of external heat into the liquid helium pipeline. At the same time, the thermal bridge can meet the deformation coordination under the action of temperature difference.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid helium storage, and in particular to a liquid helium storage tank. Background Art

[0002] Helium, a non-renewable resource, is found in very small quantities on Earth, primarily in natural gas or radioactive ores. Due to its extremely low liquid temperature range, low density, and low latent heat of vaporization, traditional double-layer vacuum powder or high-vacuum multi-layer insulated storage tanks cannot meet the requirements for long-term storage of liquid helium. Summary of the Invention

[0003] Based on this, the present invention provides a liquid helium storage tank, comprising an outer shell, a cold shield, and an inner container, which are arranged in sequence from the outside to the inside. The cold shield is wrapped around the inner container, and the outer shell is wrapped around the cold shield, forming a three-layer straight cylindrical horizontal structure. The liquid helium storage tank uses the cold shield as a boundary and fulcrum to divide the tank support into two temperature intervals. The inner container is supported on the cold shield and the outer shell, and the cold shield is supported on the outer shell. The hot end temperature of the inner container support structure can be reduced from 293K to 77K, thereby significantly reducing radiation heat transfer.

[0004] The technical solution adopted in the present invention is:

[0005] A liquid helium storage tank is a horizontal tank body, comprising:

[0006] an outer shell having a saddle disposed on its bottom;

[0007] A cold screen is disposed in the outer shell and supported on the outer shell by a cold screen support structure; a first cavity is formed between the cold screen and the outer shell;

[0008] an inner container, disposed within the cold shield and supported on the cold shield and the outer shell by an inner container support structure; the inner container is used to store liquid helium, and a second cavity is formed between the inner container and the cold shield, the second cavity being in communication with the first cavity and being in a vacuum environment;

[0009] a pipeline assembly, which is arranged through the outer shell and comprises a liquid helium pipeline, a helium gas pipeline and a connecting pipeline, which are sequentially arranged and coaxial from the inside to the outside;

[0010] One end of the liquid helium pipeline is in communication with the interior of the inner container, and the other end extends to the outside of the outer shell for discharging liquid helium;

[0011] One end of the helium pipeline is led out upward and communicates with the interior of the inner container, and the other end extends to the outside of the outer shell, for leading out the helium to form a shielding layer to prevent evaporation of liquid helium in the liquid helium pipeline;

[0012] The connecting pipe has a thermal bridge and a vacuum pipe; the vacuum pipe is located outside the outer shell and is in a vacuum state, and is used to reduce the conduction of external heat into the liquid helium pipe and the helium gas pipe;

[0013] The outer side wall of the thermal bridge is sealed to the outer shell, one end of the thermal bridge is in communication with the first cavity, and the other end is sealed to the vacuum pipe to coordinate deformation caused by temperature difference.

[0014] In the liquid helium storage tank disclosed in this application, the cold shield includes:

[0015] A cold shield cylinder wrapped around the inner container;

[0016] A coil, wound or coiled around the outer wall of the cold shield cylinder;

[0017] a liquid nitrogen container, disposed on one side of the interior of the cold shield cylinder and connected to the coil, wherein liquid nitrogen is stored as a cold source for the cold shield;

[0018] The load-bearing rings are arranged at both ends of the cold shield cylinder and are used to support the cold shield cylinder.

[0019] In the liquid helium storage tank disclosed in this application, the inner container support structure includes:

[0020] Radial supports are provided at both ends of the inner container; the radial supports are multiple in number and are connected to the inner container at one end and to the corresponding load-bearing ring at the other end in a hanging manner, for bearing loads in the lateral and vertical directions;

[0021] The axial support is a conical structure, with an end with a smaller diameter connected to the tail end of the inner container and an end with a larger diameter passing through the cold shield cylinder and connected to the outer shell.

[0022] In the liquid helium storage tank disclosed in this application, the cold shield support structure includes:

[0023] Circumferential supports, which are multiple and distributed around the bearing ring;

[0024] One end of the circumferential support is connected to the load-bearing ring, and the other end is connected to the outer shell, and is used to bear the loads of the cold shield and the inner container in the radial, axial and vertical directions.

[0025] In the liquid helium storage tank disclosed in the present application, the cold shield support structure further includes an adjustment support, and the adjustment support has:

[0026] A fixed support is provided on the outer shell, located on one side of the tail end of the cold shield cylinder, and is provided with a circular hole;

[0027] A limiting pillar, one end of which is connected to the tail end of the cold shield cylinder and the other end is arranged in the circular hole to limit the movement of the cold shield;

[0028] A movable support is provided on the outer shell and is located at the front end side of the cold shield cylinder, and is provided with an oblong hole;

[0029] A sliding support, one end of which is connected to the front end of the cold shield cylinder, and the other end of which is arranged in the oblong hole and can slide in the oblong hole to meet the deformation coordination of the cold shield.

[0030] In the liquid helium storage tank disclosed in the present application, the thermal bridge comprises an inner annular interlayer, a middle annular interlayer and an outer annular interlayer which are arranged in sequence;

[0031] The left ends of the inner annular interlayer and the outer annular interlayer are respectively connected to the first cavity, and the right ends are both closed;

[0032] The left end of the middle annular interlayer is closed, and the right end is communicated with the vacuum pipe.

[0033] In the liquid helium storage tank disclosed in the present application, the thermal bridge includes a first sleeve, a second sleeve, and a third sleeve arranged sequentially and coaxially from the inside to the outside, the outer wall of the third sleeve is sealedly connected to the outer shell, and the first sleeve is sleeved outside the helium pipeline;

[0034] The right end of the first sleeve is sealed and welded to the outer circumferential surface of the helium pipeline through a first sealing ring to form an inner annular sandwich with a closed right end;

[0035] The left end of the second sleeve is sealed and welded to the left end of the first sleeve via a second sealing ring to form a middle annular sandwich with a closed left end;

[0036] The right end of the third sleeve is sealed and welded to the right end of the second sleeve by a third sealing ring to form an outer annular sandwich with a closed right end;

[0037] The side of the third sealing ring facing away from the outer annular interlayer is butted against the vacuum pipe and sealed and welded.

[0038] In the liquid helium storage tank disclosed in the present application, a first retaining ring and a second retaining ring are sequentially embedded in the left end of the third sleeve;

[0039] The first retaining ring is freely attached to the left side of the second sealing ring, the outer diameter of the first retaining ring is equal to the inner diameter of the left end of the third sleeve, and the inner diameter is equal to the outer diameter of the helium pipeline, and the first retaining ring is provided with a through hole for connecting the inner annular interlayer, the outer annular interlayer and the first cavity;

[0040] The second retaining ring is welded to the inner circumferential surface of the left end of the third sleeve and is used to resist the left side of the first retaining ring. The inner diameter of the second retaining ring is larger than the outer circumferential diameter of the second sleeve.

[0041] In the liquid helium storage tank disclosed in the present application, a hole with a diameter larger than the outer diameter of the third sleeve is reserved on the outer shell, and a cover plate with a hole is overlapped and welded around the periphery of the hole;

[0042] The third sleeve passes through the perforated cover plate, and its outer circumferential surface is sealed and matched with the perforated cover plate by welding.

[0043] In the liquid helium storage tank disclosed in the present application, the outer surfaces of the outer shell, the cold shield cylinder, and the inner container are all provided with a heat insulation layer.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] (1) The liquid helium storage tank of the present application includes an outer shell, a cold screen and an inner container arranged in sequence from the outside to the inside. The cold screen is wrapped around the inner container, and the outer shell is wrapped around the cold screen, forming a three-layer straight cylindrical horizontal structure. The liquid helium storage tank uses the cold screen as the boundary area and fulcrum to divide the tank support into two temperature intervals. The inner container is supported on the cold screen and the outer shell, and the cold screen is supported on the outer shell. The hot end temperature of the inner container support structure can be reduced from 293K to 77K, thereby greatly reducing radiation heat transfer.

[0046] (2) The liquid helium storage tank is also provided with a helium pipeline. When the helium is discharged from the helium pipeline, a shielding layer can be formed outside the liquid helium pipeline to absorb external heat transfer, which can effectively reduce the evaporation loss of liquid helium in the liquid helium pipeline. By setting up a thermal bridge and a vacuum pipeline, a vacuum shielding layer can be formed, thereby reducing the conduction of external heat into the liquid helium pipeline. At the same time, the thermal bridge can meet the deformation coordination under the action of temperature difference.

[0047] (3) The cold screen of this application is supported on the outer shell by the cold screen support structure, and the inner container is supported on the cold screen and the outer shell by the inner container support structure. The inner container support structure has radial support and axial support. The radial support adopts a suspension method and is used to bear the loads in the lateral and vertical directions. The axial support is a conical structure and mainly bears the axial load of the transportation condition. The cold screen support structure has circumferential support and adjustable support. The circumferential support is used to bear the loads of the cold screen and the inner container in the radial, axial and vertical directions. The adjustable support is used to meet the deformation coordination of the cold screen. The support structure of this application can be applied to large container storage tanks, solving the problem of difficult support of large container storage tanks. It can not only meet the deformation coordination of the storage tank, but also achieve fixation in the working state and transportation state. At the same time, it can effectively reduce the heat conduction of the support and reduce the evaporation of the storage tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0049] Figure 1 It is a structural schematic diagram of a liquid helium storage tank;

[0050] Figure 2 This is a schematic diagram of the partial structure of the liquid helium storage tank;

[0051] Figure 3 Schematic diagram of the structure of the cold screen;

[0052] Figure 4 for Figure 3 A magnified view of point A in the figure;

[0053] Figure 5 It is a structural diagram of the axial support;

[0054] Figure 6 is a structural diagram of a pipeline component;

[0055] Figure 7 for Figure 6 Enlarged view of point B in FIG.

[0056] Figure 8 for Figure 6 Enlarged view of point C in the figure.

[0057] Reference numerals:

[0058] 10. Outer shell; 11. First cavity; 12. Saddle; 13. Hole;

[0059] 20. Cold shield; 21. Second cavity; 22. Cold shield cylinder; 23. Coil; 24. Liquid nitrogen container; 25. Bearing ring;

[0060] 30. Inner container; 31. Low temperature adsorption chamber;

[0061] 40. Pipeline assembly; 41. Liquid helium pipeline; 42. Helium pipeline; 43. Vacuum pipeline; 44. Cover plate with holes; 45. First sealing ring; 46. Second sealing ring; 47. Third sealing ring;

[0062] 50. Thermal bridge; 51. Inner annular interlayer; 52. Middle annular interlayer; 53. Outer annular interlayer; 54. First sleeve; 55. Second sleeve; 56. Third sleeve; 57. First retaining ring; 58. Second retaining ring; 59. Through hole;

[0063] 70. Cold screen support structure; 71. Circumferential support;

[0064] 80. Inner container support structure; 81. Radial support; 82. Axial support;

[0065] 90. Thermal insulation layer. DETAILED DESCRIPTION

[0066] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It will be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some, rather than all, structures related to the present application are shown in the accompanying drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0067] As used herein, the terms "comprise," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0068] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. Thus, a feature identified as "first," "second," or "third" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0069] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification are intended only to describe specific embodiments and are not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0070] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0071] See also Figures 1 to 8 As shown, the present application discloses a liquid helium storage tank. This horizontal tank comprises an outer shell 10, a cold shield 20, and an inner container 30, arranged in order from the outside to the inside. A first cavity 11 is formed between the cold shield 20 and the outer shell 10, and a second cavity 21 is formed between the inner container 30 and the cold shield 20. The second cavity 21 communicates with the first cavity 11, creating a vacuum environment. A low-temperature adsorption chamber 31 is provided on the inner container 30 to extend the vacuum life. The cold shield 20 is supported on the outer shell 10 by a cold shield support structure 70, while the inner container 30 is supported on the cold shield 20 and outer shell 10 by an inner container support structure 80. A saddle 12 is provided at the bottom of the outer shell 10. The outer shell 10 primarily ensures the vacuum level of the cavity while bearing the weight of the cold shield 20 and inner container 30, which is then transferred to the foundation via the saddle 12.

[0072] The inner container 30 is used to store liquid helium. The cold shield 20 is wrapped around the inner container 30, and the outer shell 10 is wrapped around the cold shield 20, forming a three-layer straight cylindrical horizontal structure. The liquid helium storage tank uses the cold shield 20 as the boundary and fulcrum to divide the tank support into two temperature ranges. The inner container 30 is supported on the cold shield 20 and the outer shell 10, and the cold shield 20 is supported on the outer shell 10. The hot end temperature of the inner container support structure 80 can be reduced from 293K to 77K.

[0073] The liquid helium storage tank further includes a pipeline assembly 40 , which is disposed through the outer shell 10 and includes a liquid helium pipeline 41 , a helium gas pipeline 42 , and a connecting pipeline that are sequentially and coaxially disposed from the inside to the outside.

[0074] One end of the liquid helium pipe 41 is in communication with the interior of the inner container 30 , and the other end extends to the outside of the outer shell 10 for discharging liquid helium.

[0075] One end of the helium pipe 42 is led upward and communicates with the interior of the inner container 30, and the other end extends to the outside of the outer shell 10, for conducting helium to form a shielding layer to prevent evaporation of liquid helium in the liquid helium pipe 41. That is, when conducting helium, the helium pipe 42 can form a shielding layer outside the liquid helium pipe 41 to absorb external heat transfer, which can effectively reduce the evaporation loss of liquid helium in the liquid helium pipe 41.

[0076] The connecting pipes have a heat bridge 50 and a vacuum pipe 43. The connecting pipes are all in a vacuum environment, which can form a vacuum shielding layer, thereby reducing the external heat from being conducted into the liquid helium pipe 41 and the helium gas pipe 42.

[0077] Specifically, the vacuum pipe 43 is located outside the outer shell 10 and is in a vacuum state, so as to reduce the conduction of external heat into the liquid helium pipe 41 and the helium gas pipe 42 .

[0078] Specifically, the outer wall of the thermal bridge 50 is sealed to the outer shell 10 , one end of the thermal bridge 50 is in communication with the first cavity 11 , and the other end is sealed to the vacuum pipe 43 to coordinate deformation caused by temperature difference.

[0079] In one embodiment, see Figure 3 、 4 As shown, the cold shield 20 includes a cold shield cylinder 22, a coil 23, a liquid nitrogen container 24, and a bearing ring 25. The cold shield cylinder 22 is wrapped around the inner container 30 and is made of aluminum or copper. The coil 23 is wrapped or coiled around the outer wall of the cold shield cylinder 22 and secured by a stopper. It is made of stainless steel. The liquid nitrogen container 24 is located on one side of the interior of the cold shield cylinder 22 and is connected to the coil 23. It stores liquid nitrogen, which serves as the cooling source for the cold shield 20. The bearing ring 25 is located at both ends of the cold shield cylinder 22 to support it.

[0080] The liquid nitrogen container 24 in this application provides cooling medium to the coil 23. The coil 23 and the cold shield cylinder 22 together insulate the liquid helium storage tank, reducing evaporation losses of liquid helium in the tank and extending the safe transportation time. This application also adds a stainless steel bearing ring 25 to the inner surface of the cold shield cylinder 22. This not only ensures the roundness of the cold shield cylinder 22, but also enhances the strength and rigidity of the shield. The bearing ring 25 is connected to the cold shield 20 through a specific structure, solving the problem of the cold shield 20 supporting the inner container 30.

[0081] Specifically, the stainless steel coil 23 and aluminum cooling shield cylinder 22 together form a fully enclosed liquid nitrogen cooling shield 20. Liquid nitrogen absorbs the majority of incoming heat. This fully enclosed liquid nitrogen cooling shield 20 reduces the ambient temperature around the inner container 30 to 77K, significantly reducing radiative heat transfer.

[0082] Specifically, a temperature sensor is provided on the surface of the cold shield 20 for detecting the temperature of the cold shield 20. By performing numerical simulation and temperature field analysis on the entire liquid helium storage tank, the insulation structure of the storage tank, especially the cold shield 20, can be optimized to determine the temperature of the cold shield 20 so as to more accurately calculate the heat leakage. By setting temperature test points on the cold shield 20 and analyzing the measured values ​​and theoretical values, the general rules of the cold shield 20 design can be mastered.

[0083] The existing liquid helium storage tanks are mostly insulated by high vacuum multi-layer shielding insulation. High vacuum can effectively reduce the convection heat transfer and heat conduction heat transfer of the gas in the vacuum jacket, and multi-layer shielding can reduce the radiation heat transfer. Since the radiation heat transfer is proportional to the fourth power of the temperature difference, the radiation heat transfer has the greatest impact on the heat leakage loss of the storage tank. In order to effectively reduce radiation heat transfer, the liquid helium storage tank of the present application adopts a liquid nitrogen shielding layer, which effectively reduces the evaporation loss of liquid helium through the evaporation of liquid nitrogen and extends the lossless transportation time. Usually, the structure of the liquid nitrogen screen generally adopts an aluminum screen or a copper screen wrapped with a stainless steel pipe, and then wraps the insulation material on the outside of the pipe. Although such a structure can play the role of shielding and insulation, the strength and rigidity of the aluminum screen are relatively low and cannot support the inner container 30.

[0084] The support structure determines the size of the tank's evaporation performance index. The existing support structure of the liquid helium tank can only support a small-capacity container, and the support structure has large radiation heat transfer, resulting in a large evaporation rate of the tank.

[0085] Based on this, the present application provides an inner container support structure 80 and a cold shield support structure 70 to support the inner container 30 on the cold shield 20 and the outer shell 10, and the cold shield 20 is supported on the outer shell 10. Figure 1 、 5 As shown, the inner container support structure 80 includes radial supports 81 and axial supports 82. Radial supports 81 are provided at both ends of the inner container 30, while axial supports 82 are provided at the rear end of the inner container 30. Multiple radial supports 81 are provided, each suspended, with one end connected to the inner container 30 and the other to the corresponding bearing ring 25, designed to withstand lateral and vertical loads. The axial supports 82 are conical in shape, with the smaller end connected to the rear end of the inner container 30 and the larger end extending through the cold shield cylinder 22 and connected to the outer shell 10.

[0086] Specifically, the inner container 30 adopts a 9-point support structure (eight-point radial support 81 + tail axial support 82), among which the 8-point radial support 81 mainly bears the lateral and vertical loads of the tank body under transportation and operation conditions; the tail axial support 82 mainly bears the axial load of transportation conditions, and can meet the axial and radial deformation coordination of the inner container 30 under temperature load through the initial installation angle.

[0087] Since the inner container 30 will bear an axial load of 2g under transportation conditions, an axial support 82 is required at the tail, and its support body is made of a combination of glass fiber reinforced plastic and stainless steel. Figure 5 As shown, considering the requirement of reducing heat transfer, the FRP adopts a conical structure to reduce heat conduction; considering the stress on the supporting structure, the threaded flange is made of FRP sheet material, and the middle cone structure is made of FRP rod material. The connecting flange and the cone part are locked by threads, and special glue is applied to the connecting threads for bonding and reinforcement.

[0088] Specifically, see Figure 1 、 2 As shown, the cold shield support structure 70 includes circumferential supports 71. There are multiple circumferential supports 71, which are distributed around the bearing ring 25 at a certain angle. One end of the circumferential supports 71 is connected to the bearing ring 25, and the other end is connected to the outer shell 10. They are used to bear the radial, axial and vertical loads of the cold shield 20 and the inner container 30.

[0089] Specifically, the circumferential support 71 adopts an 8-point support structure, with 4 fiberglass reinforced plastics provided at the front and rear ends respectively, and arranged at a certain angle to each other. One end of the support contacts the load-bearing ring 25 of the cold screen 20, and the other end contacts the outer shell 10, to withstand the radial, axial and vertical loads of the cold screen 20 and the inner container 30 under transportation and operation conditions.

[0090] In one embodiment, the cold shield support structure 70 further includes an adjustable support (not shown), which comprises a fixed support, a limiting strut, a movable support, and a sliding strut. The fixed support is disposed on the outer shell 10, near the rear end of the cold shield cylinder 22, and is provided with a circular hole. The limiting strut has one end connected to the rear end of the cold shield cylinder 22 and the other end disposed within the circular hole, thereby limiting the movement of the cold shield 20. The movable support is disposed on the outer shell 10, near the front end of the cold shield cylinder 22, and is provided with an oblong hole. The sliding strut has one end connected to the front end of the cold shield cylinder 22 and the other end disposed within the oblong hole, allowing it to slide within the oblong hole to ensure deformation coordination of the cold shield 20.

[0091] Under thermal loads, the cold shield 20 expands and contracts in both the axial and radial directions. The structural design of the cold shield 20 provides a fixed end at one end and a sliding end at the other. This support structure not only accommodates deformation of the cold shield 20, but also ensures its stability during operation and transportation, while effectively reducing heat conduction through the support.

[0092] The cold screen 20 of the present application is supported on the outer shell 10 by the cold screen support structure 70, and the inner container 30 is supported on the cold screen 20 and the outer shell 10 by the inner container support structure 80. The inner container support structure 80 has radial supports 81 and axial supports 82. The radial supports 81 adopt a suspension method and are used to bear loads in the lateral and vertical directions. The axial supports 82 are conical structures and mainly bear the axial loads of transportation conditions. The cold screen support structure 70 has circumferential supports 71 and adjustment supports. The circumferential supports 71 are used to bear the loads of the cold screen 20 and the inner container 30 in the radial, axial and vertical directions. The adjustment supports are used to meet the deformation coordination of the cold screen 20. The support structure of the present application is suitable for large container storage tanks, which solves the problem of difficult support of large container storage tanks. It not only meets deformation coordination, but also can achieve fixation in the working state and transportation state. At the same time, it can effectively reduce the heat conduction of the support and reduce evaporation of the storage tank.

[0093] In one embodiment, see Figures 6-8 As shown, the thermal bridge 50 comprises an inner annular interlayer 51, a middle annular interlayer 52, and an outer annular interlayer 53, which are arranged in that order. The left ends of the inner annular interlayer 51 and the outer annular interlayer 53 are respectively connected to the first cavity 11, and the right ends are both closed. The left end of the middle annular interlayer 52 is closed, and the right end is connected to the vacuum pipe 43.

[0094] Specifically, the thermal bridge 50 includes a first sleeve 54, a second sleeve 55, and a third sleeve 56, which are sequentially arranged from the inside to the outside and are coaxial. The outer wall of the third sleeve 56 is sealed with the outer shell 10, and the first sleeve 54 is sleeved outside the helium pipe 42. Figure 7 、 8 As shown, the right end of the first sleeve 54 is sealed and welded to the outer circular surface of the helium pipe 42 through the first sealing ring 45 to form an inner annular sandwich 51 with a closed right end; the left end of the second sleeve 55 and the left end of the first sleeve 54 are sealed and welded through the second sealing ring 46 to form a middle annular sandwich 52 with a closed left end; the right end of the third sleeve 56 and the right end of the second sleeve 55 are sealed and welded through the third sealing ring 47 to form an outer annular sandwich 53 with a closed right end; the side of the third sealing ring 47 facing away from the outer annular sandwich 53 is butted against the vacuum pipe 43 and sealed and welded.

[0095] Specifically, see Figure 7 As shown, a first retaining ring 57 and a second retaining ring 58 are sequentially embedded in the left end of the third sleeve 56; the first retaining ring 57 is freely attached to the left side of the second sealing ring 46, the outer diameter of the first retaining ring 57 is equal to the diameter of the inner circular surface of the left end of the third sleeve 56, and the inner diameter is equal to the diameter of the outer circular surface of the helium pipeline 42, and the first retaining ring 57 is provided with a through hole 59 for connecting the inner annular interlayer 51, the outer annular interlayer 53 and the first cavity 11; the second retaining ring 58 is welded to the inner circular surface of the left end of the third sleeve 56, and is used to support the left side of the first retaining ring 57, and the inner diameter of the second retaining ring 58 is larger than the outer circular diameter of the second sleeve 55.

[0096] Specifically, see Figure 6 As shown, the outer shell 10 has a hole 13 with a diameter larger than the outer diameter of the third sleeve 56. A perforated cover plate 44 is welded to the periphery of the hole 13. The third sleeve 56 passes through the perforated cover plate 44, and its outer circumferential surface is sealed with the perforated cover plate 44 by welding. The perforated cover plate 44 is thicker than the outer shell 10 to prevent damage to the outer shell 10 during the welding process.

[0097] The present application is provided with a helium pipeline 42. When the helium pipeline 42 is extracting helium, a shielding layer can be formed outside the liquid helium pipeline 41 to absorb external heat transfer, which can effectively reduce the evaporation loss of liquid helium in the liquid helium pipeline 41. By providing a thermal bridge 50 and a vacuum pipeline 43, a vacuum shielding layer can be formed, thereby reducing the conduction of external heat into the liquid helium pipeline 41. At the same time, the thermal bridge 50 can meet the deformation coordination under the influence of temperature differences. The three annular interlayers provided in the thermal bridge 50 of the present application can form two different and mutually intersecting vacuum shielding layers, which can further reduce the conduction of external heat into the liquid helium pipeline 41 and improve the protection effect of the liquid helium in the liquid helium pipeline 41.

[0098] The present application also supports the third sleeve 56 by providing a first retaining ring 57 and uses a second retaining ring 58 to resist the first retaining ring 57, which can effectively prevent the third sleeve 56 from shifting left and right or up and down, thereby avoiding local stress deformation at the weld between the perforated cover plate 44 and the outer shell, causing damage to the weld and leakage, thereby effectively ensuring the sealing effect.

[0099] In one embodiment, the outer surfaces of the outer shell 10, the cold shield cylinder 22, and the inner container 30 are all provided with a heat-insulating layer 90, which can significantly reduce radiant heat transfer. The heat-insulating layer 90 is a composite insulation blanket.

[0100] Based on the above embodiments, the liquid helium storage tank according to the embodiment of the present invention has the following advantages:

[0101] (1) The liquid helium storage tank of the present application includes an outer shell 10, a cold shield 20 and an inner container 30 arranged in sequence from the outside to the inside. The cold shield 20 is wrapped around the inner container 30, and the outer shell 10 is wrapped around the cold shield 20, forming a three-layer straight cylindrical horizontal structure. The liquid helium storage tank uses the cold shield 20 as the boundary and fulcrum to divide the tank support into two temperature intervals. The inner container 30 is supported on the cold shield 20 and the outer shell 10, and the cold shield 20 is supported on the outer shell 10. The hot end temperature of the inner container support structure 80 can be reduced from 293K to 77K, thereby greatly reducing radiation heat transfer.

[0102] (2) The liquid helium storage tank is also provided with a helium pipeline 42. When the helium pipeline 42 is used to discharge helium, a shielding layer can be formed outside the liquid helium pipeline 41 to absorb external heat transfer, which can effectively reduce the evaporation loss of liquid helium in the liquid helium pipeline 41. By setting up a thermal bridge 50 and a vacuum pipeline 43, a vacuum shielding layer can be formed, thereby reducing the conduction of external heat into the liquid helium pipeline 41. At the same time, the thermal bridge 50 can meet the deformation coordination under the action of temperature difference.

[0103] (3) The cold screen 20 of the present application is supported on the outer shell 10 by the cold screen support structure 70, and the inner container 30 is supported on the cold screen 20 and the outer shell 10 by the inner container support structure 80. The inner container support structure 80 has radial support 81 and axial support 82. The radial support 81 adopts a suspension method and is used to bear the loads in the lateral and vertical directions. The axial support 82 is a conical structure and mainly bears the axial load of the transportation working condition. The cold screen support structure 70 has circumferential support 71 and adjustment support. The circumferential support 71 is used to bear the loads of the cold screen 20 and the inner container 30 in the radial, axial and vertical directions. The adjustment support is used to meet the deformation coordination of the cold screen 20. The support structure of the present application is suitable for large container storage tanks, which solves the problem of difficult support of large container storage tanks. It not only meets the deformation coordination, but also can realize the fixation of the working state and the transportation state. At the same time, it can effectively reduce the heat conduction of the support and reduce the evaporation of the storage tank.

[0104] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A liquid helium storage tank, which is a horizontal tank body, characterized in that: include: an outer shell having a saddle disposed on its bottom; A cold screen is disposed in the outer shell and supported on the outer shell by a cold screen support structure; A first cavity is formed between the cold shield and the outer shell; an inner container, disposed within the cold shield and supported on the cold shield and the outer shell by an inner container support structure; the inner container is used to store liquid helium, and a second cavity is formed between the inner container and the cold shield, the second cavity being in communication with the first cavity and being in a vacuum environment; a pipeline assembly, which is arranged through the outer shell and comprises a liquid helium pipeline, a helium gas pipeline and a connecting pipeline, which are sequentially arranged and coaxial from the inside to the outside; One end of the liquid helium pipeline is in communication with the interior of the inner container, and the other end extends to the outside of the outer shell for discharging liquid helium; One end of the helium pipeline is led out upward and communicates with the interior of the inner container, and the other end extends to the outside of the outer shell, for leading out the helium to form a shielding layer to prevent evaporation of liquid helium in the liquid helium pipeline; The connecting pipe has a thermal bridge and a vacuum pipe; the vacuum pipe is located outside the outer shell and is in a vacuum state, and is used to reduce the conduction of external heat into the liquid helium pipe and the helium gas pipe; The outer wall of the thermal bridge is sealed to the outer shell, one end of the thermal bridge is in communication with the first cavity, and the other end is sealed to the vacuum pipe, so as to coordinate the deformation caused by the temperature difference; A hole with a diameter larger than the outer diameter of the thermal bridge is reserved on the outer shell, and a perforated cover plate is welded to the periphery of the hole; the thermal bridge passes through the perforated cover plate and its outer surface is sealed with the perforated cover plate by welding.

2. The liquid helium storage tank according to claim 1, characterized in that: The cold screen comprises: A cold shield cylinder wrapped around the inner container; A coil, wound around the outer wall of the cold shield cylinder; a liquid nitrogen container, disposed on one side of the interior of the cold shield cylinder and connected to the coil, wherein liquid nitrogen is stored as a cold source for the cold shield; The load-bearing rings are arranged at both ends of the cold shield cylinder and are used to support the cold shield cylinder.

3. The liquid helium storage tank according to claim 2, characterized in that: The inner container support structure comprises: Radial supports are provided at both ends of the inner container; the radial supports are multiple in number and are connected to the inner container at one end and to the corresponding load-bearing ring at the other end in a hanging manner, for bearing loads in the lateral and vertical directions; The axial support is a conical structure, with an end with a smaller diameter connected to the tail end of the inner container and an end with a larger diameter passing through the cold shield cylinder and connected to the outer shell.

4. The liquid helium storage tank according to claim 2, characterized in that: The cold screen support structure comprises: Circumferential supports, which are multiple and distributed around the bearing ring; One end of the circumferential support is connected to the load-bearing ring, and the other end is connected to the outer shell, and is used to bear the loads of the cold shield and the inner container in the radial, axial and vertical directions.

5. The liquid helium storage tank according to claim 4, characterized in that: The cold screen support structure further includes an adjustment support, wherein the adjustment support has: A fixed support is provided on the outer shell, located on one side of the tail end of the cold shield cylinder, and is provided with a circular hole; A limiting pillar, one end of which is connected to the tail end of the cold shield cylinder and the other end is arranged in the circular hole to limit the movement of the cold shield; A movable support is provided on the outer shell and is located at the front end side of the cold shield cylinder, and is provided with an oblong hole; A sliding support, one end of which is connected to the front end of the cold shield cylinder, and the other end of which is arranged in the oblong hole and can slide in the oblong hole to meet the deformation coordination of the cold shield.

6. The liquid helium storage tank according to claim 1 or 5, characterized in that: The thermal bridge comprises an inner annular interlayer, a middle annular interlayer and an outer annular interlayer arranged in sequence; The left ends of the inner annular interlayer and the outer annular interlayer are respectively connected to the first cavity, and the right ends are both closed; The left end of the middle annular interlayer is closed, and the right end is communicated with the vacuum pipe.

7. The liquid helium storage tank according to claim 6, characterized in that: The thermal bridge comprises a first sleeve, a second sleeve, and a third sleeve, which are sequentially arranged from the inside to the outside and are coaxial. The outer wall of the third sleeve is sealed with the outer shell. The first sleeve is sleeved outside the helium pipeline. The right end of the first sleeve is sealed and welded to the outer circumferential surface of the helium pipeline through a first sealing ring to form an inner annular sandwich with a closed right end; The left end of the second sleeve is sealed and welded to the left end of the first sleeve via a second sealing ring to form a middle annular sandwich with a closed left end; The right end of the third sleeve is sealed and welded to the right end of the second sleeve by a third sealing ring to form an outer annular sandwich with a closed right end; The side of the third sealing ring facing away from the outer annular interlayer is butted against the vacuum pipe and sealed and welded.

8. The liquid helium storage tank according to claim 7, characterized in that: A first retaining ring and a second retaining ring are sequentially embedded in the left end of the third sleeve; The first retaining ring is freely attached to the left side of the second sealing ring, the outer diameter of the first retaining ring is equal to the inner diameter of the left end of the third sleeve, and the inner diameter is equal to the outer diameter of the helium pipeline, and the first retaining ring is provided with a through hole for connecting the inner annular interlayer, the outer annular interlayer and the first cavity; The second retaining ring is welded to the inner circumferential surface of the left end of the third sleeve and is used to resist the left side of the first retaining ring. The inner diameter of the second retaining ring is larger than the outer circumferential diameter of the second sleeve.

9. The liquid helium storage tank according to claim 8, characterized in that: The third sleeve passes through the perforated cover plate and its outer circumferential surface is sealed and matched with the perforated cover plate by welding.

10. The liquid helium storage tank according to claim 2, characterized in that: The outer surfaces of the outer shell, the cold shield cylinder and the inner container are all provided with a heat insulation layer.

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