A method for preparing a low-heat-leakage helium cell and its vacuum sealing.

Abstract

The present invention discloses a method for preparing a low-heat-leakage helium tank and a vacuum sealing method thereof, relating to the technical field of cryogenic liquids. The method comprises: S1, evenly winding a glass ribbon coated with room-temperature-curing epoxy resin around the bottom of a threaded end of a G10 cylinder, and evenly winding the glass ribbon along the thread to an angled step; S2, coating the glass ribbon with room-temperature-curing epoxy resin, connecting a stainless steel cylinder to the G10 cylinder along the thread, and pouring room-temperature-curing epoxy resin mixed with glass fiber chips into the gap between the stainless steel cylinder and the G10 cylinder until it is filled; S3, inserting a sealing reinforcement ring from the other end of the G10 cylinder, wherein the annular outer diameter of the sealing reinforcement ring is the same as the maximum outer diameter of the stainless steel cylinder at the embedding point; the low-heat-leakage helium tank preparation and the vacuum sealing method thereof, wherein the G10 cylinder is introduced into the helium tank structure. This insulating material has excellent thermal insulation performance and mechanical strength under low-temperature conditions, significantly reduces heat leakage of the helium tank, and effectively reduces the loss of liquid helium.

Description

Technical Field

[0001] This invention relates to the field of cryogenic liquid technology, specifically to a method for preparing a low-heat-leakage helium tank and its vacuum sealing. Background Technology

[0002] Superconducting materials, due to their superior properties such as high current density and high upper critical field at low temperatures, are widely used in high-field magnets, superconducting energy storage, large particle colliders, and superconducting magnetic resonance imaging. However, the critical temperature of traditional superconducting materials generally does not exceed 23K, thus requiring immersion in liquid hydrogen or liquid helium to achieve a superconducting state. Since liquid hydrogen has a higher temperature than liquid helium and is explosive, liquid helium, due to its lower temperature and safety, has become the preferred coolant for superconducting magnets.

[0003] Besides superconductivity, liquid helium is widely used in large-scale scientific instruments, semiconductor manufacturing, and medical equipment—fields requiring ultra-low temperature environments. Liquid helium is typically stored using liquid helium dewars, but due to its extremely low temperature, low latent heat, and high volatility, long-term storage remains a technical challenge. Therefore, sealing performance is a crucial consideration in the design of liquid helium dewars, directly impacting storage efficiency and operating costs. Chinese patent application CN221035234 U discloses a liquid helium container that partially solves the problems of inconvenience and stability caused by the large temperature difference between the container's outer wall and the air. However, this container does not adequately address the issue of sealing performance. If the container's sealing performance is insufficient, liquid helium will exchange heat with the external environment, leading to rapid evaporation and resource waste. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing a low-heat-leaking helium cell and its vacuum sealing, thereby solving the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a low-heat-leaking helium cell and its vacuum sealing method, the method comprising:

[0006] S1. Wrap glass ribbon coated with room temperature curing epoxy resin evenly around the bottom of the threaded end of the G10 cylinder, and wrap the glass ribbon evenly along the thread to the beveled step.

[0007] S2. Coat the glass ribbon with room temperature curing epoxy resin, connect the stainless steel cylinder to the G10 cylinder along the thread, and fill the gap between the stainless steel cylinder and the G10 cylinder with room temperature curing epoxy resin mixed with glass fiber fragments until it is full.

[0008] S3. Insert the sealing reinforcement ring from the other end of the G10 cylinder. The outer diameter of the sealing reinforcement ring is the same as the maximum outer diameter of the nested part of the stainless steel cylinder.

[0009] S4. Wrap glass ribbon coated with room temperature curing epoxy resin around the joint between the sealing reinforcing ring and the stainless steel cylinder, and fill the gap between the sealing reinforcing ring and the G10 cylinder with room temperature curing epoxy resin mixed with glass fiber fragments.

[0010] S5. By allowing the epoxy resin to stand for more than 12 hours, the room temperature curing epoxy resin is fully cured, thereby achieving a vacuum seal for the low-heat-leakage helium tank.

[0011] Preferably, the G10 cylinder is made of insulating structural material of low-temperature superconducting magnets.

[0012] Preferably, the glass ribbon is made of alkali-free aluminoborosilicate glass fiber.

[0013] Preferably, the room temperature curing epoxy resin is subjected to vacuum treatment with a vacuum degree of 7.2×10²Pa before use to remove internal air bubbles and improve the sealing effect.

[0014] Preferably, when the stainless steel cylinder is threadedly connected to the G10 cylinder, room temperature curing epoxy resin is extruded from the thread into the overflow groove to form an initial seal.

[0015] Preferably, the sealing reinforcement ring enhances the overall sealing performance and low-temperature mechanical strength of the helium tank through multiple seals with the stainless steel cylinder and the G10 cylinder.

[0016] Preferably, the outer diameter of the sealing reinforcement ring is the same as the maximum outer diameter of the nested part of the stainless steel cylinder to ensure consistent sealing after installation.

[0017] Preferably, the width of the glass ribbon wrapped around the joint between the sealing reinforcing ring and the stainless steel cylinder is 25 mm, and the wrapping thickness is about 0.5 mm.

[0018] Preferably, the room-temperature curing epoxy resin injected into the gap between the sealing reinforcing ring and the G10 cylinder is mixed with glass fiber fragments, and the mixture is gently stirred after injection to prevent bubble formation.

[0019] Preferably, the sealing performance of the low-leaking helium tank is verified by a helium mass spectrometer leak detector, which achieves a vacuum degree of 3.9 Pa and a background leakage rate of approximately 2.1 Pa·m³ / s during leak detection.

[0020] As can be seen from the above technical solution, the present invention has the following beneficial effects:

[0021] This invention relates to a low-heat-leakage helium tank fabrication method and its vacuum sealing technique. By introducing a G10 cylinder into the helium tank structure, this insulating material exhibits excellent thermal insulation and mechanical strength at low temperatures. Compared to traditional stainless steel, it significantly reduces heat leakage from the helium tank, effectively minimizing liquid helium loss. Multiple seals are achieved at the connection area between the G10 and stainless steel cylinders, as well as at the installation location of the sealing reinforcement ring, using glass fiber ribbons and glass fiber fragments coated with room-temperature curing epoxy resin. This multi-seal design ensures the vacuum sealing performance of the helium tank while improving the low-temperature strength of the structure. The room-temperature curing epoxy resin undergoes vacuum treatment before use to effectively remove internal air bubbles, further enhancing the stability of the seal performance and preventing sealing defects caused by air bubbles. The design of the sealing reinforcement ring matches the outer diameter of the stainless steel cylinder, ensuring the integrity of the sealing structure after installation and preventing seal failure due to dimensional inconsistencies. During the sealing process, an epoxy resin overflow groove effectively accommodates excess epoxy resin, ensuring the integrity of the initial seal at the threaded connection and simplifying the construction process. Both the G10 material and glass fiber products used in this invention possess low-temperature resistance and high strength characteristics. To ensure the stability and reliability of the helium tank in extremely low temperature environments, multiple sealing designs and leak tests have confirmed that the helium tank achieves a vacuum level of 3.9 Pa and a background leakage rate of approximately 2.1 Pa·m³ / s with no significant fluctuations, meeting the stringent requirements for liquid helium storage and applications. By improving the helium tank structure and sealing methods, the evaporation loss of liquid helium is significantly reduced, providing reliable technical support for efficient liquid helium storage. This invention is applicable to superconducting fields and other cryogenic liquid storage scenarios. Compared to traditional designs, this invention improves the thermal insulation performance and service life of the helium tank through improved materials and optimized sealing processes, reducing liquid helium consumption and operating costs, thus bringing economic benefits to users. Attached Figure Description

[0022] Figure 1 This is a flowchart of the method of the present invention;

[0023] Figure 2 This is a schematic diagram of the overall structure of the present invention;

[0024] Figure 3 This is a schematic diagram of the sealing area of ​​the present invention;

[0025] Figure 4 This is a schematic diagram of the G10 cylindrical structure of the present invention;

[0026] Figure 5 This is a schematic diagram of the sealing process of the present invention;

[0027] Figure 6 This is a schematic diagram showing the sealing process of the present invention.

[0028] In the diagram: 1. Stainless steel cylinder; 101. Stainless steel upper cylinder; 102. Stainless steel lower cylinder; 2. G10 cylinder; 3. Flange; 4. Sealing reinforcing ring; 5. Sealing area; 6. Primary sealing area; 7. Room temperature curing epoxy resin overflow groove; 8. Secondary sealing area; 9. Tertiary sealing area; 10. Quaternary sealing area; 11. Angled step. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] like Figure 1 As shown, a method for preparing a low-heat-leakage helium cell and its vacuum sealing is described, the method comprising:

[0031] Wrap glass ribbon coated with room temperature curing epoxy resin evenly around the bottom of the threaded end of G10 cylinder 2, and wrap the glass ribbon evenly along the thread to the angled step 11.

[0032] A room temperature curing epoxy resin is coated on a glass ribbon. The stainless steel cylinder 1 is connected to the G10 cylinder 2 along the thread. The gap between the stainless steel cylinder 1 and the G10 cylinder 2 is filled with a room temperature curing epoxy resin mixed with glass fiber fragments until it is full.

[0033] Insert the sealing reinforcement ring 4 into the other end of the G10 cylinder 2. The outer diameter of the sealing reinforcement ring is the same as the maximum outer diameter of the nested part of the stainless steel cylinder 1.

[0034] Wrap glass ribbon coated with room temperature curing epoxy resin at the joint between the sealing reinforcing ring 4 and the stainless steel cylinder 1, and fill the gap between the sealing reinforcing ring 4 and the G10 cylinder 2 with room temperature curing epoxy resin mixed with glass fiber fragments.

[0035] Allow it to stand for more than 12 hours to allow the room temperature curing epoxy resin to fully cure, thereby achieving a vacuum seal for the low-heat-leakage helium tank.

[0036] This invention employs a multi-layered, multi-material vacuum sealing technology to minimize heat leakage and gas permeation. After curing, the epoxy resin forms a high-strength, high-sealing-performance filling layer. Its combination with the glass fiber ribbon enhances interfacial adhesion, preventing thermal expansion mismatch caused by temperature differences. The threaded connection between the stainless steel cylinder 1 and the G10 cylinder 2 provides a preliminary mechanical seal, while the epoxy resin filling further prevents gas leakage through minute gaps. The sealing reinforcement ring 4, in conjunction with the multi-layered epoxy resin structure, creates a superimposed sealing effect, ensuring the overall mechanical strength and low heat leakage performance. Furthermore, the mixing of glass fiber fragments during epoxy resin infusion improves the viscosity and uniformity of the filling material, effectively preventing bubble formation and enhancing the crack resistance of the cured layer. This invention significantly reduces heat leakage: the multi-layered sealing technology reduces heat loss from the helium tank, greatly extending the operating time of the cryogenic superconducting magnet and conserving helium resources. It also improves sealing reliability: the multi-layered structural design ensures excellent stability and durability of the seal at low temperatures, preventing seal failure due to temperature fluctuations. Enhanced overall strength: The reinforcing sealing ring provides additional mechanical support in critical areas, optimizing the sealing system's resistance to deformation and improving structural rigidity in a vacuum environment. Reduced manufacturing complexity: This invention avoids a complex high-temperature curing process by using room-temperature curing epoxy resin, making operation simple and efficient.

[0037] The G10 cylinder 2 utilizes the insulating structural material of cryogenic superconducting magnets to ensure excellent insulation performance and mechanical stability under low-temperature conditions. G10 material is made of glass fiber reinforced epoxy resin, possessing high strength, low thermal conductivity, and good dielectric properties. It maintains an extremely low coefficient of thermal expansion even at low temperatures, thus avoiding stress concentration caused by temperature differences. As an insulating material, G10 also prevents current leakage, improving the safety of superconducting magnet operation. G10 exhibits excellent mechanical strength and dimensional stability at liquid helium temperatures, effectively preventing thermal stress damage. As a dedicated insulating material for cryogenic superconducting magnets, G10 possesses outstanding dielectric constant and high-voltage resistance. Even under prolonged operation and repeated temperature cycling, G10 material maintains reliable performance, thereby extending the service life of the helium tank.

[0038] The fiberglass ribbon is made of alkali-free aluminoborosilicate glass fiber, possessing excellent mechanical strength and low-temperature resistance. Due to its unique chemical composition and manufacturing process, alkali-free aluminoborosilicate glass fiber exhibits high flexibility and mechanical strength in low-temperature environments. The amorphous structure of this material effectively resists crack propagation and prevents material fracture caused by stress concentration. Furthermore, its good compatibility with epoxy resin ensures a robust interfacial bond during curing, enhancing the overall sealing effect.

[0039] Room temperature curing epoxy resin undergoes vacuum treatment (7.2 × 10² Pa) before use to remove internal air bubbles and improve sealing performance. During the curing process, the presence of internal air bubbles can easily degrade the sealing performance of epoxy resin. Vacuum treatment removes air bubbles and dissolved gases from the epoxy resin, reducing porosity in the cured material and significantly improving sealing quality. Vacuum treatment also enhances the flowability of the epoxy resin, making it easier to penetrate gaps and ensuring uniform coverage of every interface. Removing air bubbles results in a denser cured layer, significantly reducing the risk of microleakage. Vacuum treatment improves the viscosity control of the epoxy resin, ensuring uniform sealing layer thickness. The absence of air bubbles in the sealed area prevents localized stress concentration and seal failure caused by bubble rupture.

[0040] When the stainless steel cylinder 1 is threadedly connected to the G10 cylinder 2, room temperature curing epoxy resin is extruded from the threads into the overflow groove 7, forming an initial seal. During the threaded connection, the epoxy resin, as a sealing medium, is evenly distributed within the thread gap. When the stainless steel cylinder 1 and the G10 cylinder 2 are tightened, the epoxy resin is forced into the gap as the thread torque increases, and some excess epoxy resin is squeezed into the overflow groove 7. The overflow groove not only collects excess epoxy resin but also provides external support for the initial seal after curing. The epoxy resin in the overflow groove, after curing, becomes an additional sealing barrier, enhancing the stability of the initial seal. Excess epoxy resin is effectively collected, avoiding waste and increasing the reliability of the sealing structure. A dedicated overflow groove is provided to control the extrusion range of the epoxy resin and keep other components clean.

[0041] The sealing reinforcement ring 4 enhances the overall sealing performance and cryogenic mechanical strength of the helium tank through multiple seals with the stainless steel cylinder 1 and the G10 cylinder 2. As the core support component of the connection area, the sealing reinforcement ring 4 forms a superimposed sealing structure through reasonable nesting and epoxy resin bonding. This multi-layered sealing ensures that even in extreme low-temperature or high-pressure environments, if any one sealing layer fails, the others can still provide protection. Simultaneously, the sealing reinforcement ring 4, as a mechanical support component, evenly distributes the stress in the sealing area 5, preventing seal failure caused by localized deformation. This multi-seal design significantly improves the reliability and durability of the overall sealing system of the helium tank. The sealing reinforcement ring 4 maintains high mechanical strength in extremely low-temperature environments, ensuring the stability of the helium tank. The multi-seal structure disperses stress concentration at the joints, extending the service life of the seal.

[0042] The outer diameter of the sealing reinforcement ring 4 is the same as the maximum outer diameter of the nested area of ​​the stainless steel cylinder 1 to ensure consistent sealing after installation. Maintaining a precise mechanical fit between the outer diameter of the sealing reinforcement ring 4 and the maximum outer diameter of the nested area of ​​the stainless steel cylinder 1 ensures no loosening or displacement during installation, while also creating a seamless nested connection between the sealing reinforcement ring and surrounding components, preventing uneven gaps or stress concentrations at the interface. Precise control of the outer diameter ensures the fit and airtightness of each sealing element. The consistent outer diameter of the sealing reinforcement ring allows it to remain stable in low-temperature environments, preventing seal failure due to thermal expansion and contraction. Standardized dimensional design reduces tolerance requirements during production and assembly, improving manufacturing efficiency.

[0043] The fiberglass tape wrapped around the joint between the sealing reinforcing ring 4 and the stainless steel cylinder 1 is 25 mm wide and approximately 0.5 mm thick. The 25 mm wide fiberglass tape covers a larger joint area, effectively distributing stress at the joint. The approximately 0.5 mm thickness provides sufficient sealing strength while maintaining good adhesion and flexibility, preventing uneven epoxy resin curing due to excessive thickness. This configuration ensures the stability of the sealed area under external forces. The width and thickness of the fiberglass tape optimize the sealing effect at the joint, preventing gas leakage. Appropriate thickness and width improve the shear and tensile strength of the joint, reducing the risk of deformation. Standardized tape width and thickness facilitate mass production and quality control.

[0044] Glass fiber fragments are mixed into the room-temperature curing epoxy resin injected into the gap between the sealing reinforcing ring 4 and the G10 cylinder 2, and the mixture is gently stirred after injection to prevent air bubble formation. The epoxy resin mixed with glass fiber fragments has higher viscosity and filling capacity, providing additional support and bonding during curing. Gentle stirring evenly distributes the glass fiber fragments and removes air bubbles, avoiding sealing defects caused by bubble bursts or uneven curing. The addition of glass fiber fragments improves the strength and toughness of the epoxy resin while reducing shrinkage during curing. Gentle stirring significantly reduces the bubble formation rate, improving the density and stability of the sealing area. By improving adhesion and mechanical strength, the service life of the helium tank is significantly extended.

[0045] The sealing performance of the low-leakage helium tank was verified using a helium mass spectrometer leak detector. During leak detection, the vacuum level reached 3.9 Pa, and the background leakage rate was approximately 2.1 Pa·m³ / s. The helium mass spectrometer leak detector assesses sealing performance by detecting trace amounts of helium leakage. The 3.9 Pa vacuum level ensures high sensitivity of the detection environment, and the 2.1 Pa·m³ / s background leakage rate represents the lowest detection limit of the detection system, accurately reflecting the actual sealing effect of the helium tank. Using a helium mass spectrometer leak detector allows for rapid and accurate assessment of sealing quality and the detection of minute leaks. Strict leak detection standards ensure that each helium tank meets design requirements. Leak verification effectively improves product reliability and market competitiveness.

[0046] This low-heat-leakage helium tank has excellent mechanical and sealing properties, which can significantly reduce radiative heat transfer with the liquid helium external dewar, thereby reducing liquid helium loss.

[0047] like Figures 2-6 As shown, this helium tank includes a stainless steel upper cylinder 101, a stainless steel lower cylinder 102, a G10 cylinder 2, a flange 3, and a sealing reinforcing ring 4. The stainless steel upper cylinder 101 and the stainless steel lower cylinder 102 are connected to the G10 cylinder 2 by threads; the sealing reinforcing ring 4 connects the stainless steel upper cylinder 101, the stainless steel lower cylinder 102, and the G10 cylinder 2 to achieve multiple seals.

[0048] Compared to ordinary helium tanks, the low-heat-leakage helium tank of the present invention adds a G10 cylinder 2. Since G10 material has better thermal insulation and mechanical properties than stainless steel in low-temperature environments, the helium tank of the present invention significantly reduces heat leakage compared to traditional stainless steel helium tanks.

[0049] Compared to ordinary helium tanks, the low-leakage helium tank described herein incorporates glass fiber ribbons and glass fiber fragments coated with room-temperature curing epoxy resin. These glass fiber ribbons and fragments are made of alkali-free, aluminoborosilicate glass fiber, which exhibits high heat resistance, low moisture absorption, flexibility, high tensile strength, and good insulation properties. This invention improves the mechanical and sealing properties of the helium tank by adding glass fiber ribbons and glass fiber fragments coated with room-temperature curing epoxy resin.

[0050] The room-temperature curing epoxy resin used for sealing is a high-performance, instant-drying product. It has a uniform black color distribution, no delamination, and comes in a variety of specifications. It exhibits good adhesion to metals, rubber, and plastics. The room-temperature curing epoxy resin needs to be placed in a container and evacuated (vacuum degree approximately 7.2 × 10⁻⁶). 2 Pa), to expel as much air and air bubbles as possible from inside.

[0051] The connection area between the stainless steel upper cylinder 101, the stainless steel lower cylinder 102, and the G10 cylinder 2 is a sealing area. This sealing area 5 can achieve multiple seals for the stainless steel upper cylinder 101, the stainless steel lower cylinder 102, and the G10 cylinder 2.

[0052] Specifically, firstly, fiberglass tape coated with room temperature curing epoxy resin is evenly wrapped around the bottom of the threaded end of the G10 cylinder 2;

[0053] Specifically, the glass ribbon is evenly wound along the thread of the G10 cylinder 2 to the angled step 11. After the winding is completed, room temperature curing epoxy resin is applied to the glass ribbon.

[0054] Specifically, the stainless steel upper cylinder 101 is screwed onto the G10 cylinder 2 along the thread. After screwing, room temperature curing epoxy resin mixed with glass fiber fragments is injected into the gap between the stainless steel upper cylinder 101 and the G10 cylinder 2 until it is full. At the same time, part of the room temperature curing epoxy resin on the glass fiber strip at the thread is squeezed into the room temperature curing epoxy resin overflow groove 7.

[0055] Specifically, a sealing reinforcing ring 4 is inserted from the other end of the G10 cylinder 2. The outer diameter of the ring is the same as the maximum outer diameter of the nested part of the stainless steel upper cylinder 101. During the insertion process, the sealing reinforcing ring 4 is aligned with the stainless steel upper cylinder 101.

[0056] Specifically, fiberglass ribbon coated with room temperature curing epoxy resin is wrapped around the joint between the sealing reinforcing ring 4 and the stainless steel upper cylinder 101; the fiberglass ribbon is 25mm wide and about 0.5mm thick.

[0057] Specifically, sufficient amount of room temperature curing epoxy resin mixed with glass fiber fragments is injected into the gap between the sealing reinforcing ring 4 and the G10 cylinder 2. The room temperature curing epoxy resin needs to be gently stirred to prevent air bubbles from entering and affecting the sealing performance. Finally, it is left to stand for more than 12 hours to allow the room temperature curing epoxy resin to cure.

[0058] The helium tank prepared and sealed according to the present invention includes a process of pouring room temperature curing epoxy resin mixed with glass fiber fragments;

[0059] The sealed area optimizes the sealing performance and cryogenic mechanical properties of this helium tank.

[0060] The flange 3 is connected to the liquid helium external Dewar via fittings.

[0061] The sealing between the lower stainless steel cylinder 102 and the G10 cylinder 2 is the same as the sealing between the upper stainless steel cylinder 101 and the G10 cylinder 2 described above. Finally, the sealing performance of this helium tank was verified by connecting the test assembly to a helium mass spectrometer leak detector, turning on the leak detector, and waiting until the vacuum level reached 3.9 Pa, with a background leakage rate of approximately 2.1 Pa × m. 3Helium gas was sprayed along each joint of the test piece at a rate of / s. During leak testing, the leak rate at the leak detector showed no significant fluctuation, indicating that the test piece could maintain the vacuum seal requirement at room temperature.

[0062] The vacuum sealing method proposed in this invention can significantly improve the sealing performance and low-temperature strength of the helium tank, and greatly reduce heat leakage between liquid helium and the external Dewar, thereby reducing the loss of liquid helium.

[0063] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a low-heat-leaking helium cell and its vacuum sealing, characterized in that, The method comprises: S1. Wrap glass ribbon coated with room temperature curing epoxy resin evenly around the bottom of the threaded end of the G10 cylinder, and wrap the glass ribbon evenly along the thread to the inclined step of the G10 cylinder. S2. Coat the glass ribbon with room temperature curing epoxy resin, connect the stainless steel upper cylinder to the G10 cylinder along the thread, and fill the gap between the stainless steel upper cylinder and the G10 cylinder with room temperature curing epoxy resin mixed with glass fiber fragments until it is full. S3. Insert the sealing reinforcement ring from the other end of the G10 cylinder. The outer diameter of the sealing reinforcement ring is the same as the maximum outer diameter of the nested part of the stainless steel upper cylinder. S4. Wrap glass ribbon coated with room temperature curing epoxy resin around the joint between the sealing reinforcing ring and the stainless steel upper cylinder, and fill the gap between the sealing reinforcing ring and the G10 cylinder with room temperature curing epoxy resin mixed with glass fiber fragments; when the stainless steel upper cylinder is threadedly connected to the G10 cylinder, the room temperature curing epoxy resin is squeezed out from the thread into the overflow groove, forming the initial seal; the sealing steps between the stainless steel lower cylinder and the G10 cylinder are the same as the sealing steps between the stainless steel upper cylinder and the G10 cylinder. S5. By allowing the epoxy resin to stand for more than 12 hours, the room temperature curing epoxy resin is fully cured, thereby achieving a vacuum seal for the low-heat-leakage helium tank.

2. The method for preparing a low-heat-leaking helium cell and its vacuum sealing according to claim 1, characterized in that: The G10 cylinder is made of insulating structural material of low-temperature superconducting magnets.

3. The method for preparing a low-heat-leaking helium cell and its vacuum sealing according to claim 1, characterized in that: The glass ribbon is made of alkali-free aluminoborosilicate glass fiber.

4. The method for preparing a low-heat-leaking helium cell and its vacuum sealing according to claim 1, characterized in that: The room temperature curing epoxy resin is subjected to vacuum treatment before use, with a vacuum degree of 7.2 × 10⁻⁶. 2 Pa, to remove internal air bubbles and improve the sealing effect.

5. The method for preparing a low-heat-leaking helium cell and its vacuum sealing according to claim 1, characterized in that: The glass ribbon wrapped around the joint between the sealing reinforcement ring and the stainless steel upper cylinder is 25 mm wide and 0.5 mm thick.

6. The method for preparing a low-heat-leaking helium cell and its vacuum sealing according to claim 1, characterized in that: Glass fiber fragments are mixed in the room temperature curing epoxy resin injected into the gap between the sealing reinforcing ring and the G10 cylinder, and the mixture is gently stirred after injection to prevent air bubbles from forming.

7. The method for preparing a low-heat-leaking helium cell and its vacuum sealing according to claim 1, characterized in that: The sealing performance of the low-leakage helium tank was verified by a helium mass spectrometer leak detector, which achieved a vacuum level of 3.9 Pa and a background leakage rate of 2.1 Pa·m during leak detection. 3 / s.

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