Knife-edge high-temperature sealing structure for superconducting cavities and superconducting cavity structure

Abstract

This invention discloses a knife-edge type high-temperature sealing structure for a superconducting cavity and the superconducting cavity structure itself. Specifically, it includes a bundle tube, a first flange, a second flange, and a high-temperature sealing element. The first and second flanges are respectively fitted onto the bundle tube. The high-temperature sealing element is disposed on the end face of the first flange near the second flange. A knife-edge structure is provided on the end face of the second flange near the high-temperature sealing element, with the knife-edge structure facing the high-temperature sealing element. The first and second flanges are fixed by a pre-tightening component, and the high-temperature sealing element is fitted into the knife-edge structure. The knife-edge type high-temperature sealing structure and the high-temperature glass fiber sealing element achieve reliable line sealing and long-term stability of the superconducting cavity outlet at high temperatures.

Description

Technical Field

[0001] This invention relates to the field of superconducting magnet technology, specifically to a knife-edge type high-temperature sealing structure for superconducting cavities and a superconducting cavity structure. Background Technology

[0002] Superconducting cavities are widely used in high-energy accelerators, particle physics experiments, and high-precision electronic devices. Their stable operation requires extremely high standards for the vacuum environment and sealing of the cooling medium inside the cavity. Especially at the cavity outlet and the bundle tube interface, the sealing structure must be able to maintain stable sealing performance over a long period of time under high-temperature conditions (such as about 700°C) to prevent internal liquid leakage or external gas intrusion, thereby ensuring the vacuum integrity and operational reliability of the superconducting cavity.

[0003] In existing technologies, high-temperature sealing of superconducting cavities mainly relies on sealing solutions using metal gaskets (such as copper or silver gaskets) or flexible graphite or spiral wound gaskets combined with flange knife edges. Flexible graphite and spiral wound gaskets achieve a certain degree of high-temperature sealing by pressing them into the flange knife edges. However, these existing solutions still have significant limitations in practical applications: flexible graphite gaskets are prone to outgassing in ultra-high vacuum environments, potentially leading to internal cavity contamination; simultaneously, their strength and elasticity significantly decrease under sustained high temperatures, making it difficult to maintain a stable sealing pressure. Furthermore, spiral wound gaskets are prone to creep relaxation under high temperatures and repeated thermal cycling conditions, reducing sealing force and leading to seal failure.

[0004] Furthermore, there is a difference in the coefficient of thermal expansion between the existing gasket material and the metal flange. Under repeated and drastic temperature changes, micro-gaps or permanent deformation can easily occur at the interface, leading to seal failure. Especially in the high-temperature region at the outlet of the superconducting cavity, the seal may leak liquid or break the vacuum due to thermal stress and deformation, affecting the safe operation of the cavity.

[0005] In summary, current technologies lack an outlet sealing solution that can simultaneously achieve low leakage rate, resistance to thermal deformation, and long-term structural stability at ultra-high temperatures. Summary of the Invention

[0006] The purpose of this invention is to provide a knife-edge type high-temperature sealing structure for superconducting cavities and a superconducting cavity structure, so as to solve the technical problem that existing high-temperature seals for superconducting cavities are easily affected by material creep and thermal expansion mismatch, leading to leakage or vacuum failure.

[0007] To achieve this objective, the present invention adopts the following technical solution: A knife-edge type high-temperature sealing structure for a superconducting cavity includes a bundle tube, a first flange, a second flange, and a high-temperature sealing element. The first flange and the second flange are respectively sleeved on the bundle tube. The high-temperature sealing element is disposed on the end face of the first flange near the second flange. A knife-edge structure is disposed on the end face of the second flange near the high-temperature sealing element. The knife-edge structure is directly opposite to the high-temperature sealing element. The first flange and the second flange are fixed by a pre-tightening member. The high-temperature sealing element is fitted with the knife-edge structure. The high-temperature sealing element is a fiber structure.

[0008] Optionally, the inner peripheral wall of the end face of the first flange near the second flange is set as a slope, and a protrusion is provided on the end face of the second flange near the first flange. The knife-edge structure is provided on the end face of the protrusion near the second flange, and the protrusion is annular and its outer peripheral wall matches the shape of the slope.

[0009] Optionally, the high-temperature seal is disposed on the inclined surface, the inner peripheral wall of the high-temperature seal is fitted with the bundle tube, and the outer peripheral wall of the high-temperature seal is fitted with the inclined surface.

[0010] Optionally, a first gap is provided between the first flange and the bundle tube, and the horizontal cross-section of the first gap is annular.

[0011] Optionally, a second gap is provided between the second flange and the bundle tube, and the horizontal cross-section of the second gap is annular.

[0012] Optionally, the outer diameter of the first gap is larger than the outer diameter of the second gap.

[0013] Optionally, the cutting edge structure includes a first cutting edge and a second cutting edge, both of which are annular groove structures, and the horizontal cross-sectional areas of the first cutting edge and the second cutting edge increase sequentially from top to bottom.

[0014] Optionally, the inner diameter of the bottom surface of the first cutting edge is greater than the outer diameter of the bottom surface of the second cutting edge; the vertical section height of the first cutting edge is greater than the vertical section height of the second cutting edge.

[0015] Optionally, the high-temperature sealant is made of high-temperature glass fiber.

[0016] A superconducting cavity structure includes a superconducting cavity body and a knife-edge high-temperature sealing structure for the superconducting cavity as described above, wherein the knife-edge high-temperature sealing structure for the superconducting cavity is installed on the superconducting cavity body.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention involves placing a high-temperature sealing element on the first flange end face and forming a knife-edge structure on the second flange end face, ensuring a tight fit between the high-temperature sealing element and the knife-edge structure. With the flanges at both ends of the bundle tube fixed by pre-tightening components, this structure maintains stable line-sealed contact under high-temperature conditions, fully utilizing the elasticity and creep resistance of the high-temperature sealing element to effectively compensate for the microscopic deformation and thermal stress generated by the flange and sealing element during thermal cycling. Simultaneously, the knife-edge structure precisely presses the high-temperature sealing element in, ensuring a tight seal at the sealing interface, significantly reducing the risk of leakage and guaranteeing the integrity of the liquid seal and vacuum environment at the superconducting cavity outlet under 700°C conditions. Furthermore, the high-temperature sealing element is a fiber structure, which possesses elasticity and can achieve a tight fit within the annular groove of the knife-edge structure. It also fully adapts to the microscopic morphological changes of the flange and bundle tube under high-temperature thermal cycling, absorbing minor dimensional changes caused by thermal expansion and creep, thereby improving reliability and stability. Therefore, this structure not only improves the reliability and long-term stability of high-temperature sealing, but also improves the sealing failure problem caused by creep, softening or venting of traditional metal or graphite gaskets under extreme conditions, achieving a significant performance improvement in high-temperature sealing technology for superconducting cavities. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0020] Figure 1 This is a schematic cross-sectional view of the knife-edge type high-temperature sealing structure for a superconducting cavity provided in an embodiment of the present invention; Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 This is a schematic diagram showing the dimensions of a knife-edge type high-temperature sealing structure for a superconducting cavity provided in an embodiment of the present invention; Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure along BB.

[0021] Illustration: 10, bundle tube; 20, first flange; 30, second flange; 40, high-temperature seal; 50, knife-edge structure; 501, protrusion; 510, first knife edge; 520, second knife edge; 60, first gap; 70, second gap; 80, bolt hole. Detailed Implementation

[0022] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0023] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0024] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1: The knife-edge high-temperature sealing structure for superconducting cavities provided in this embodiment is applied to scenarios where liquid sealing and vacuum isolation are required at the outlet of a superconducting cavity during high-temperature sintering, heat treatment, or high-temperature operation. In this embodiment, reliable line sealing and long-term stability of the superconducting cavity outlet at 700°C are achieved through the knife-edge high-temperature sealing structure and high-temperature glass fiber seal.

[0026] Please see Figure 1 , Figure 2 and Figure 4The knife-edge type high-temperature sealing structure for superconducting cavities provided in this embodiment includes a bundle tube 10, a first flange 20, a second flange 30, and a high-temperature sealing element 40. The first flange 20 and the second flange 30 are respectively sleeved on the bundle tube 10. The high-temperature sealing element 40 is disposed on the end face of the first flange 20 near the second flange 30. A knife-edge structure 50 is disposed on the end face of the second flange 30 near the high-temperature sealing element 40. The knife-edge structure 50 and the high-temperature sealing element 40 are directly opposite each other. The first flange 20 and the second flange 30 are fixed by a pre-tightening member. The high-temperature sealing element 40 is fitted with the knife-edge structure 50.

[0027] Specifically, the high-temperature seal 40 is disposed on the end face of the first flange 20 near the second flange 30. The high-temperature seal 40 can be made of high-temperature resistant fiber material, such as high-temperature glass fiber braided or filled structure. This material can maintain excellent elasticity and creep resistance at 700℃, and its low gas leakage rate can effectively avoid vacuum contamination. The end face of the second flange 30 near the high-temperature seal 40 is machined with an annular knife edge structure 50. The geometric parameters of the knife edge structure 50 include the knife edge angle, tip radius, and depth. It can be optimized according to the thickness and elastic characteristics of the seal to ensure that the high-temperature seal 40 can be precisely fitted with the knife edge during assembly.

[0028] The aforementioned knife-edge structure 50 is a line-pressed metal flange structure well-known to those skilled in the art, and therefore will not be described in detail in this embodiment. During actual assembly, the first flange 20 and the second flange 30 are fixed with bolts or other pre-tightening components, and an appropriate pre-tightening force is applied to embed the knife-edge structure 50 into the high-temperature sealing element 40, forming a stable line-sealing interface. This ensures that the sealing element fully conforms to the flange end face and utilizes the elasticity of the sealing element to adapt to microscopic unevenness and thermal stress deformation generated during thermal cycling, thereby maintaining the continuity of the sealing contact and stability at high temperatures. This structure, through reasonable matching of flange materials, knife-edge geometry, and the characteristics of the high-temperature sealing element 40, achieves low leakage rate and high reliability sealing under extreme high temperature and thermal cycling conditions. It prevents liquid leakage inside the superconducting cavity and ensures the integrity of the cavity's vacuum environment. Compared to traditional metal or graphite gasket sealing solutions, it effectively improves failure problems caused by creep, softening, and venting, thereby significantly improving the overall performance of the high-temperature sealing technology at the superconducting cavity outlet.

[0029] Furthermore, the inner peripheral wall of the end face of the first flange 20 near the second flange 30 is set as a bevel, and a protrusion 501 is provided on the end face of the second flange 30 near the first flange 20. A knife-edge structure 50 is provided on the end face of the protrusion 501 near the second flange 30. The protrusion 501 is annular, and its outer peripheral wall matches the bevel shape. Specifically, the annular protrusion 501 is provided on the end face of the second flange 30 near the first flange 20, and the outer peripheral wall of the protrusion 501 matches the bevel shape of the inner peripheral wall of the first flange 20, so that the two flanges can achieve self-guidance and precise alignment during assembly, thereby ensuring that the high-temperature seal 40 and the knife-edge structure 50 can be accurately aligned. The knife-edge structure 50 is provided on the side of the protrusion 501 near the end face of the second flange 30. The knife-edge can be a wire-pressed metal knife-edge structure 50 well known in the art, and its geometric parameters such as angle, tip radius, and height can be designed and optimized according to the thickness and elastic characteristics of the high-temperature seal 40. In actual assembly, the high-temperature seal 40 is placed on the end face of the first flange 20. The first flange 20 and the second flange 30 are fixed by bolts or other pre-tightening components. Under the action of pre-tightening force, the knife-edge structure 50 is embedded in the high-temperature seal 40 to form a stable line sealing interface. The cooperation between the protrusion 501 and the bevel not only realizes the guiding and positioning function between the flanges, but also maintains the relative stability between the flanges under high-temperature thermal cycling, so that the knife-edge structure 50 and the high-temperature seal 40 maintain precise fitting. Through the above design, the sealing interface can make full use of the elasticity and creep resistance of the high-temperature seal 40, adapt to microscopic unevenness and thermal stress deformation, significantly reduce the risk of leakage, and ensure the integrity of the liquid seal and vacuum environment at the superconducting cavity outlet under the high-temperature condition of 700℃.

[0030] Furthermore, the high-temperature seal 40 is disposed on the inclined surface, with its inner peripheral wall fitting against the bundle tube 10 and its outer peripheral wall fitting against the inclined surface. Specifically, the fitting of the inner peripheral wall of the high-temperature seal 40 against the bundle tube 10 ensures that the seal is supported and fixed in position by the bundle tube 10 in the radial direction, preventing radial displacement or deformation under high temperature. The fitting of the outer peripheral wall against the inclined surface provides guidance and pre-pressure to the flange end face of the seal, allowing the high-temperature seal 40 to precisely engage with the knife-edge structure 50 of the second flange 30 under the bolt pre-tightening force. This design enables the high-temperature seal 40 to be evenly stressed along the inclined surface when in contact with the knife-edge structure 50, improving the tightness of the knife-edge engagement with the seal, thereby maintaining the continuity and stability of the line sealing interface during high-temperature thermal cycling and effectively reducing the risk of leakage.

[0031] Meanwhile, the fit between the inclined surface and the outer peripheral wall of the seal can compensate for minor angular errors between the flanges and stress caused by thermal expansion, allowing the elasticity of the seal to be fully utilized, further enhancing sealing performance and long-term reliability. Through the synergistic effect of the fit between the inner peripheral wall and the bundle tube 10 and the fit between the outer peripheral wall and the inclined surface, the high-temperature seal 40 can stably withstand radial and axial stresses under high-temperature thermal cycling, achieving high-precision fitting between the knife-edge structure 50 and the seal. This ensures the integrity of the liquid seal and vacuum environment at the superconducting cavity outlet under extreme high-temperature conditions, and significantly improves the failure problems caused by creep, softening, or gas release of traditional metal or graphite gaskets at high temperatures.

[0032] Furthermore, a first gap 60 is provided between the first flange 20 and the bundle tube 10, and the horizontal cross-section of the first gap 60 is annular. Specifically, the first gap 60 provided between the first flange 20 and the bundle tube 10 has an annular horizontal cross-section. The aforementioned gap can be achieved using an annular void structure well known to those skilled in the art, and therefore will not be elaborated upon. The high-temperature sealing element 40 is disposed on the inclined surface of the end face of the first flange 20 near the second flange 30. Its inner peripheral wall is in contact with the bundle tube 10, and its outer peripheral wall is in contact with the inclined surface, so as to effectively constrain radial and axial stress and ensure the stable positioning of the sealing element under high-temperature conditions.

[0033] The first gap 60 allows the high-temperature seal 40 to extend slightly in the radial or axial direction when the knife-edge structure 50 is engaged with the high-temperature seal 40, without hindering the complete fit between the first flange 20 and the second flange 30. This avoids the problem of insufficient contact between the flange end faces due to seal thickness or elastic deformation. Under the action of bolt preload, the high-temperature seal 40 is tightly engaged with the knife-edge structure 50 of the second flange 30. The buffer space provided by the first gap 60 can absorb the slight dimensional changes of the seal during thermal expansion or creep, maintaining the continuity and uniform stress of the line sealing interface, significantly reducing the risk of leakage and enhancing the reliability of the high-temperature seal.

[0034] Through the coordinated design of the first gap 60 and the high-temperature sealing element 40, the sealing structure can not only compensate for thermal stress and micro-unevenness at high temperatures, but also ensure the complete fit of the first flange 20 and the second flange 30 under high-temperature conditions. This effectively improves the liquid sealing and vacuum environment stability of the superconducting cavity outlet under high-temperature conditions of 700℃. At the same time, it improves the sealing failure problem caused by the easy creep, softening or gas release of traditional metal or graphite gaskets at high temperatures, and realizes the long-term reliability and performance improvement of the high-temperature sealing structure.

[0035] Furthermore, a second gap 70 is provided between the second flange 30 and the bundle tube 10, and the horizontal cross-section of the second gap 70 is annular. Specifically, the setting of the second gap 70 ensures that the second flange 30 can slide smoothly along the bundle tube 10, and effectively transmits the pressing force to the high-temperature sealing element 40 under the action of bolt pre-tightening force, so that the knife edge structure 50 and the sealing element form a stable and uniform mating interface.

[0036] Furthermore, the outer diameter of the first gap 60 is larger than the outer diameter of the second gap 70. Specifically, when the high-temperature seal 40 is subjected to bolt pre-tightening force and tightly fitted with the knife-edge structure 50 of the second flange 30, the annular space of the first gap 60 can provide buffer and extension space for the high-temperature seal 40, absorbing the small dimensional changes of the seal during thermal expansion or creep, thereby preventing the high-temperature seal 40 from being pressed into the first gap 60 and causing gaps to appear on the contact surfaces of the first flange 20 and the second flange 30, while ensuring that the first flange 20 and the second flange 30 can be completely fitted under pre-tightening conditions.

[0037] Furthermore, the knife-edge structure 50 includes a first knife-edge 510 and a second knife-edge 520, both of which are annular groove structures. The horizontal cross-sectional areas of the first knife-edge 510 and the second knife-edge 520 increase sequentially from top to bottom. Specifically, the annular grooves of the first knife-edge 510 and the second knife-edge 520 gradually increase from top to bottom, allowing the high-temperature seal 40 to initially contact from the narrow end during insertion and gradually expand the force to the wide end, thereby forming a progressive compression force distribution from top to bottom. This ensures the initial tightness of the high-temperature seal 40 within the knife-edge and maintains uniform compression under high-temperature thermal cycling conditions, avoiding excessive local stress that could lead to seal damage or uneven compression. The superimposed arrangement of the first knife-edge 510 and the second knife-edge 520 further increases the sealing contact area, enabling the seal to form a multi-point pressing interface within the annular groove, effectively increasing the line seal length and sealing reliability, while also enhancing its adaptability to high-temperature thermal expansion and creep.

[0038] Furthermore, the inner diameter of the bottom surface of the first cutting edge 510 is larger than the outer diameter of the bottom surface of the second cutting edge 520; the vertical section height of the cutting edge is greater than the vertical section height of the second cutting edge 520. Specifically, the difference in bottom surface dimensions and height between the first cutting edge 510 and the second cutting edge 520 allows the high-temperature sealing element 40 to form a layered, progressively pressing state when embedded in the cutting edges. First, the first cutting edge 510 contacts the upper part of the sealing element and applies an initial pressing force. Then, the sealing element gradually expands to the second cutting edge 520, achieving a gradual transition and uniform distribution of the pressing force. The difference in vertical height ensures that the sealing element maintains a stable mating position during high-temperature expansion or creep, and provides sufficient vertical space to absorb minor dimensional changes caused by thermal expansion, avoiding local displacement or uneven compression of the sealing element. The inner diameter of the bottom surface of the first cutting edge 510 is larger than the outer diameter of the bottom surface of the second cutting edge 520, which enables the seal to form a self-centering guide during the embedding process, ensuring that the seal and the cutting edge fit precisely. At the same time, it increases the contact area between the seal and the annular groove, improving the sealing reliability of the line seal interface.

[0039] Furthermore, the high-temperature seal 40 is made of high-temperature glass fiber. Specifically, high-temperature glass fiber is a special fiber material that is resistant to high temperatures, has a low coefficient of thermal expansion, a low gas leakage rate, and excellent elastic recovery capabilities. It can maintain structural stability and elastic properties under high-temperature conditions of 700℃ and above. Using high-temperature glass fiber as a seal not only allows the seal to achieve a tight fit within the annular groove of the knife-edge structure 50, but also fully adapts to the microscopic morphological changes of the flange and bundle tube 10 under high-temperature thermal cycling, absorbing the minute dimensional changes caused by thermal expansion and creep. The excellent elasticity of high-temperature glass fiber enables it to form a stable line sealing interface with the knife edge under the action of bolt preload, and can adapt to microscopic unevenness, thereby significantly improving sealing reliability and preventing liquid leakage and gas intrusion.

[0040] Furthermore, the low outgassing rate of high-temperature glass fiber effectively reduces the risk of gas release in ultra-high vacuum environments, avoiding the sealing failure problems caused by oxidation, softening, or creep relaxation of traditional graphite or metal gaskets at high temperatures. Therefore, by selecting high-temperature glass fiber as the high-temperature sealing element 40, this embodiment not only improves the liquid sealing and vacuum sealing performance of the superconducting cavity outlet under extreme high-temperature conditions, but also significantly enhances the long-term reliability and stability of the sealing structure, providing a reliable material basis for high-temperature sealing technology of superconducting cavities.

[0041] For the convenience of those skilled in the art, refer to Figure 3As shown, the inner diameter of the bundle tube 10 is the first dimension D1, and the outer diameter of the bundle tube 10 is the second dimension D2. Bolt holes 80 are provided on the first flange 20 and the second flange 30, arranged in a circumferential array along the circumference of the third dimension D3. The outer diameter of both the first flange 20 and the second flange 30 is the fourth dimension D4, where the fourth dimension D4 is larger than the third dimension D3, the third dimension D3 is larger than the second dimension D2, and the second dimension D2 is larger than the first dimension D1. For reference, the fourth dimension D4 is 110 mm, the third dimension D3 is 95 mm, the second dimension D2 is 66 mm, and the first dimension D1 is 60 mm.

[0042] In summary, the knife-edge high-temperature sealing structure for superconducting cavities provided in this embodiment achieves reliable line sealing and long-term stability of the superconducting cavity outlet at high temperatures through the knife-edge high-temperature sealing structure and high-temperature glass fiber seal.

[0043] Example 2: This embodiment also provides a superconducting cavity structure, including a superconducting cavity body and a knife-edge type high-temperature sealing structure for the superconducting cavity as described in Embodiment 1. The knife-edge type high-temperature sealing structure for the superconducting cavity is installed on the superconducting cavity body. Specifically, the knife-edge type high-temperature sealing structure for the superconducting cavity can be fixedly connected to the superconducting cavity body by welding, bonding, or other methods. The dimensions of the knife-edge type high-temperature sealing structure for the superconducting cavity are adaptively adjusted according to the superconducting cavity body; this embodiment does not impose specific limitations.

[0044] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A knife-edge type high-temperature sealing structure for superconducting cavities, characterized in that, The device includes a bundle tube (10), a first flange (20), a second flange (30), and a high-temperature seal (40). The first flange (20) and the second flange (30) are respectively sleeved on the bundle tube (10). The high-temperature seal (40) is disposed on the end face of the first flange (20) near the second flange (30). The end face of the second flange (30) near the high-temperature seal (40) is provided with a knife-edge structure (50). The knife-edge structure (50) is disposed opposite to the high-temperature seal (40). The first flange (20) and the second flange (30) are fixed by a pre-tightening member. The high-temperature seal (40) is fitted with the knife-edge structure (50). The high-temperature seal (40) is a fiber structure.

2. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 1, characterized in that, The inner peripheral wall of the first flange (20) near the second flange (30) is set as a slope, and the second flange (30) near the first flange (20) is provided with a protrusion (501). The knife-edge structure (50) is provided on the end face of the protrusion (501) near the second flange (30). The protrusion (501) is annular and its outer peripheral wall matches the shape of the slope.

3. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 2, characterized in that, The high-temperature seal (40) is disposed on the inclined surface, the inner peripheral wall of the high-temperature seal (40) is fitted with the bundle tube (10), and the outer peripheral wall of the high-temperature seal (40) is fitted with the inclined surface.

4. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 1, characterized in that, A first gap (60) is provided between the first flange (20) and the bundle tube (10), and the horizontal cross section of the first gap (60) is annular.

5. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 4, characterized in that, A second gap (70) is provided between the second flange (30) and the bundle tube (10), and the horizontal cross section of the second gap (70) is annular.

6. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 5, characterized in that, The outer diameter of the first gap (60) is larger than the outer diameter of the second gap (70).

7. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 3, characterized in that, The blade structure (50) includes a first blade (510) and a second blade (520). Both the first blade (510) and the second blade (520) are annular groove structures. The horizontal cross-sectional areas of the first blade (510) and the second blade (520) increase sequentially from top to bottom.

8. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 7, characterized in that, The inner diameter of the bottom surface of the first cutting edge (510) is greater than the outer diameter of the bottom surface of the second cutting edge (520); the vertical section height of the first cutting edge (510) is greater than the vertical section height of the second cutting edge (520).

9. The knife-edge type high-temperature sealing structure for superconducting cavities according to claim 3, characterized in that, The high-temperature sealing element (40) is made of high-temperature glass fiber.

10. A superconducting cavity structure, characterized in that, It includes a superconducting cavity body and a knife-edge high-temperature sealing structure for a superconducting cavity as described in any one of claims 1-9, wherein the knife-edge high-temperature sealing structure for a superconducting cavity is installed on the superconducting cavity body.

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