A composite heat-insulating bellows for superconducting acceleration module and superconducting acceleration module

Abstract

The present invention discloses a compound insulated bellows for superconducting acceleration module and a superconducting acceleration module, which are mainly connected to a room temperature vacuum chamber through a hot end compound pipe. The structural characteristics of the hot end compound pipe increase the heat transfer distance from the bellows and the hot end flange, avoiding the problem of unstable bellows structure caused by increasing the number of corrugations. The main technical scheme of the present invention is: a compound insulated bellows for superconducting acceleration module, comprising: a bellows, a cold end pipe, a cold end flange, a hot end compound pipe and a hot end flange; the cold end pipe is connected to the first end of the bellows, the hot end compound pipe is connected to the second end of the bellows away from the first end, the cold end flange is connected to one end of the cold end pipe away from the bellows, and the hot end flange is connected to one end of the hot end compound pipe away from the bellows. The present invention is mainly used to provide a beam pipeline in a superconducting acceleration module.

Description

Technical Field

[0001] The invention relates to the technical field of low-temperature superconductivity, and in particular to a composite heat-insulating bellows used in a superconducting acceleration module and a superconducting acceleration module. Background Art

[0002] A bellows is usually set in the superconducting acceleration module. The bellows is a beam pipe working in a low-temperature and vacuum environment. The bellows connects the core low-temperature components of the superconducting acceleration module and the room-temperature vacuum chamber. The bellows is used for vacuum insulation and reducing heat leakage. Specifically, on the one hand, the beam vacuum environment inside the bellows ensures that the charged particles in the superconducting acceleration module can work normally, and the insulating vacuum outside the bellows reduces the radiation heat leakage of the environment to the low-temperature components. On the other hand, the bellows can increase the effective heat transfer length, thereby reducing heat leakage along the tube wall.

[0003] Existing bellows are difficult to balance structural stability and thermal insulation performance. For example, when the number of corrugations in a bellows is too large, the bellows structure is unstable and radial deformation occurs, thereby reducing the effective aperture when the beam passes through and increasing the risk of the bellows being punctured. When the number of corrugations in the bellows is reduced, the effective heat transfer length will decrease, resulting in increased heat conduction and heat leakage along the wall of the bellows. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a compound insulation bellows for a superconducting acceleration module and a superconducting acceleration module, which are mainly used to solve the problem that the bellows in the prior art are difficult to balance structural stability and thermal insulation performance.

[0005] In order to achieve the above object, the present invention mainly provides the following technical solutions:

[0006] In one aspect, the present invention provides a composite insulation bellows for a superconducting acceleration module, comprising:

[0007] A bellows (100), a cold end pipe (200), a cold end flange (300), a hot end compound pipe (400) and a hot end flange (500);

[0008] The cold end pipe (200) is connected to the first end of the bellows (100), the hot end compound pipe (400) is connected to the second end of the bellows (100) away from the first end, the cold end flange (300) is connected to one end of the cold end pipe (200) away from the bellows (100), and the hot end flange (500) is connected to one end of the hot end compound pipe (400) away from the bellows (100).

[0009] The hot end composite pipe (400) comprises at least two sub-pipes, which are sequentially sleeved toward the outer layer, and adjacent sub-pipes are arranged at intervals, and two ends of any current sub-pipe located in the middle are respectively connected to a sub-pipe located in the outer layer of the current sub-pipe and a sub-pipe located in the inner layer of the current sub-pipe;

[0010] The bellows (100) is connected to the end of the sub-joining pipe located at the outermost side, and the hot end flange (500) is connected to the end of the sub-joining pipe located at the innermost side.

[0011] Part of the ends of the sub-pipes extend into the corrugated tube (100).

[0012] The hot end composite pipe (400) comprises a first sub-pipe (410), a second sub-pipe (420) and a third sub-pipe (430); the second sub-pipe (420) is sleeved on the outer periphery of the first sub-pipe (410), and a gap is provided between the second sub-pipe (420) and the first sub-pipe (410); the third sub-pipe (430) is sleeved on the outer periphery of the second sub-pipe (420), and a gap is provided between the third sub-pipe (430) and the second sub-pipe (420);

[0013] The two ends of the second sub-tube (420) are respectively connected to the first end of the first sub-tube (410) and the first end of the third sub-tube (430), the second end of the first sub-tube (410) is connected to the hot end flange (500), and the second end of the third sub-tube (430) is connected to the bellows (100);

[0014] The first sub-connecting pipe (410) and the second sub-connecting pipe (420) extend from the first end of the first sub-connecting pipe (410) into the corrugated pipe (100).

[0015] The bellows (100) comprises a tube body (110) and a hot end joint (120), the hot end joint (120) is connected to the tube body (110), and the hot end joint (120) is located at the second end of the bellows (100);

[0016] The minimum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end flange (500). The hot end compound pipe (400) is connected to the hot end joint (120). The maximum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end joint (120).

[0017] The cold end pipe (200) and the cold end flange (300) have the same inner diameter.

[0018] The bellows (100) is a thin-walled welded bellows, and the inner diameter of the bellows (100) is greater than the inner diameter of the cold end pipe (200).

[0019] Wherein, the cold end flange (300) and the hot end flange (500) are both slip-on flanges.

[0020] Among them, the compound insulation bellows also includes:

[0021] The thermal isolation connecting ring (600) is a thin-walled ring, the thermal isolation connecting ring (600) is connected to the second end of the bellows (100), and the thermal isolation connecting ring (600) is used to connect the cooling belt of the superconducting acceleration module.

[0022] On the other hand, the present invention also provides a superconducting accelerating module, comprising any of the aforementioned compound insulation bellows.

[0023] The compound insulation bellows and superconducting acceleration module proposed by the present invention are connected to the room temperature vacuum chamber through the hot end compound pipe. The structural characteristics of the hot end compound pipe can achieve the isolation of the beam vacuum inside the bellows and the insulation vacuum outside the bellows, while increasing the heat transfer distance between the bellows and the hot end flange, greatly reducing the heat introduced from the hot end to the bellows in a limited axial space, and then there is no need to increase the number of corrugations of the bellows to reduce heat leakage, achieve both insulation and ensure the stability of the bellows structure. At the same time, due to the setting of the compound structure of the hot end compound pipe, the overall axial length of the compound insulation bellows will not be increased or will be slightly increased, avoiding excessive occupation of the axial space of the compound insulation bellows. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of a compound insulation bellows for a superconducting acceleration module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation method, structure, characteristics and effects of a composite insulation bellows for a superconducting acceleration module proposed by the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0026] On the one hand, if Figure 1 As shown, an embodiment of the present invention provides a composite insulation bellows for a superconducting acceleration module, comprising:

[0027] A bellows (100), a cold end pipe (200), a cold end flange (300), a hot end compound pipe (400) and a hot end flange (500);

[0028] The cold end pipe (200) is connected to the first end of the bellows (100), the hot end compound pipe (400) is connected to the second end of the bellows (100) away from the first end, the cold end flange (300) is connected to one end of the cold end pipe (200) away from the bellows (100), and the hot end flange (500) is connected to one end of the hot end compound pipe (400) away from the bellows (100).

[0029] Figure 1 In the figure, the area A located above the dotted line is the cross-sectional structure of the compound insulation bellows, and the area B located below the dotted line is the main structure of the compound insulation bellows observed from the outside.

[0030] The corrugated tube (100) may further include a tube body (110), a hot end joint (120) and a cold end joint (130). The tube body (110) is a cylindrical structure and is a tube material with a wave-like appearance. The hot end joint (120) and the cold end joint (130) are respectively located at the axial ends of the tube body (110) and can be fixedly connected to the tube body (110) by welding. The hot end joint (120) and the cold end joint (130) are both annular disc structures with a central opening. The tube body (110) is a thin-walled tube body. The thin-walled structure can reduce the heat transfer area along the tube wall of the corrugated tube (100), while the corrugated structure of the tube body (110) can increase the heat transfer length along the tube wall. In the heat conduction process, the amount of heat is proportional to the heat transfer area and inversely proportional to the heat transfer length. Therefore, the design of the thin-walled welded bellows (100) can reduce the heat conduction from two aspects: reducing the heat transfer area and extending the heat transfer length. In addition, the bellows (100) has a scalable structure and can also compensate for the axial deformation caused by low-temperature shrinkage.

[0031] The cold end pipe (200) is connected to the cold end connector (130), which may be welded or integrally formed. The cold end pipe (200) may be a cylindrical pipe. In some embodiments, the axial length of the cold end pipe (200) is less than the axial length of the pipe body (110), thereby avoiding excessive occupation of the axial space by the cold end pipe (200) and ensuring that the heat transfer length is increased as much as possible in the limited axial space.

[0032] The hot end composite pipe (400) is connected to the hot end joint (120) by welding or integral molding. The hot end composite pipe (400) can be a composite structure of various specific forms, such as a plurality of cylindrical structures stacked together, or a structure with a nested relationship, in order to increase the heat transfer distance between the hot end flange (500) and the hot end joint (120) and reduce heat transfer. The distance is described in detail below.

[0033] The cold end flange (300) is connected to the superconducting cavity or superconducting solenoid in the superconducting acceleration module, and the temperature is 2K or 4K. The hot end flange (500) is connected to the room temperature end, that is, the room temperature vacuum chamber, and the temperature is about 300K. The entire compound insulation bellows is a transition structure from low temperature to room temperature, and its heat conduction and heat leakage are one of the main heat loads of the superconducting acceleration module. The present application greatly reduces the heat leakage through the above-mentioned structural setting, and ensures the working performance of the superconducting acceleration module.

[0034] The compound insulation bellows and superconducting acceleration module for superconducting acceleration module proposed in the embodiment of the present invention are connected to the room temperature vacuum chamber through the hot end compound pipe. Through the structural characteristics of the hot end compound pipe, the beam vacuum inside the bellows and the insulation vacuum outside the bellows are isolated, and the heat transfer distance between the bellows and the hot end flange is increased, which greatly reduces the heat introduced from the hot end to the bellows in a limited axial space. Then, there is no need to increase the number of corrugations of the bellows to reduce heat leakage, and both insulation and structural stability of the bellows are achieved. At the same time, due to the setting of the compound structure of the hot end compound pipe, the overall axial length of the compound insulation bellows will not be increased or will be slightly increased, avoiding excessive occupation of the axial space of the compound insulation bellows.

[0035] In one embodiment, the hot end composite pipe (400) includes at least two sub-pipes, which are sequentially sleeved toward the outer layer, and adjacent sub-pipes are arranged at intervals, and the two ends of any current sub-pipe located in the middle are respectively connected to the sub-pipe located in the outer layer of the current sub-pipe and the sub-pipe located in the inner layer of the current sub-pipe. The bellows (100) is connected to the end of the sub-pipe located on the outermost side, and the hot end flange (500) is connected to the end of the sub-pipe located on the innermost side.

[0036] The sub-tube is a cylindrical structure, and the inner diameters of at least two sub-tubes are different, so that at least two sub-tubes can be sequentially sleeved on the outer layer, and the spacing distances between adjacent sub-tubes in the radial direction of the sub-tube can be consistent. Any sub-tube located in the middle is used as the current sub-tube, and one end of the current sub-tube is connected to a sub-tube sleeved on the outside of the current sub-tube, and the other end of the current sub-tube is connected to a sub-tube penetrated inside the current sub-tube, and then at least two sub-tubes are connected to form a compound tube that is wave-bent from the outer circle to the inner circle. This arrangement increases the heat conduction distance while reducing the occupation of the axial space. The bellows (100) is connected to the end of the sub-tube located on the outermost side, and can be a hot end joint (120) connected to the end of the sub-tube located on the outermost side.

[0037] In one embodiment, the ends of some sub-tubes extend into the bellows (100), for example, except for the sub-tube connected to the hot end joint (120), other sub-tubes including a partial area of ​​one end relative to the tube body (110) extend into the tube body (110) through the central opening of the hot end joint (120). Due to the inwardly stacked structure of the hot end composite tube (400), the inner diameter of the bellows (100) or the tube body (110) is enlarged without changing the structure of the hot end flange (500), that is, the tube body (110) and the hot end composite tube (400) have a stacked area in the radial direction, so that the bellows (100) is far away from the accelerated particle beam. At the same time, the hot end composite tube (400) acts as an inner lining to isolate the bellows (100) and the beam, thereby protecting the bellows (100), reducing the risk of the bellows (100) being punctured, and providing double protection for the bellows.

[0038] In a more specific implementation, Figure 1 The middle hot end compound pipe (400) comprises a first sub-pipe (410), a second sub-pipe (420) and a third sub-pipe (430), wherein the second sub-pipe (420) is sleeved on the outer periphery of the first sub-pipe (410), and a gap is provided between the second sub-pipe (420) and the first sub-pipe (410), and the third sub-pipe (430) is sleeved on the outer periphery of the second sub-pipe (420), and a gap is provided between the third sub-pipe (430) and the second sub-pipe (420). The two ends of the second sub-pipe (420) are respectively connected to the first end of the first sub-pipe (410) and the first end of the third sub-pipe (430), the second end of the first sub-pipe (410) is connected to the hot end flange (500), and the second end of the third sub-pipe (430) is connected to the bellows (100).

[0039] That is, the second sub-pipe (420) is the current sub-pipe located in the middle position, while the first sub-pipe (410) is the innermost sub-pipe, and the third sub-pipe (430) is the outermost sub-pipe. The radial spacing between the first sub-pipe (410) and the second sub-pipe (420) and the second sub-pipe (420) and the third sub-pipe (430) can be the same. The first sub-pipe (410), the second sub-pipe (420) and the third sub-pipe (430) can be welded in sequence or integrally formed, but the connection between the first sub-pipe (410), the second sub-pipe (420) and the third sub-pipe (430) should be airtight to a certain extent. The first sub-pipe (410) and the second sub-pipe (420) extend from the first end of the first sub-pipe (410) into the bellows (100). Specifically, the axial length of the second sub-tube (420) is greater than the axial length of the third sub-tube (430), the second end of the second sub-tube (420) is connected to the first end of the third sub-tube (430), the first end of the second sub-tube (420) will extend into the pipe body (110) from the central opening of the hot end joint (120), the first end of the first sub-tube (410) is connected to the first end of the second sub-tube (420) in the pipe body (110), the axial length of the first sub-tube (410) can be greater than the axial length of the second sub-tube (420), and then the second end of the first sub-tube (410) extends out of the second sub-tube (420) and is connected to the hot end flange (500). The advantages are not repeated.

[0040] In one embodiment, the bellows (100) comprises a tube body (110) and a hot end joint (120), the hot end joint (120) is connected to the tube body (110), and the hot end joint (120) is located at the second end of the bellows (100). The minimum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end flange (500), the hot end compound pipe (400) is connected to the hot end joint (120), and the maximum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end joint (120).

[0041] The hot end compound pipe (400) achieves the function of increasing the inner diameter of the pipe body (110) without changing the inner diameter of the hot end flange (500). The minimum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end flange (500), thereby ensuring that the beam forward channel is not affected.

[0042] In one embodiment, the cold end pipe (200) and the cold end flange (300) have the same inner diameter, which ensures that the beam forward passage is not affected and reserves installation space for the outer bolts of the cold end pipe (200).

[0043] In one embodiment, the inner diameter of the bellows (100) or the tube body (110) is larger than the inner diameter of the cold end pipe (200), thereby keeping the tube body (110) away from the accelerated particle beam, reducing the risk of the bellows (100) or the tube body (110) being punctured. However, it is understood that the inner diameter of the cold end pipe (200) is consistent with the inner diameter of the central opening of the cold end connector (130), thereby preventing the beam forward passage from being affected.

[0044] In one embodiment, the cold end flange (300) and the hot end flange (500) are both slip-on flanges, or metal sealing slip-on flanges. The cold end flange (300) further includes a cold end flange (310) and a cold end flange body (320), the cold end flange (310) is connected to the cold end pipe (200) and extends outward from the cold end pipe (200), the cold end flange body (320) is sleeved on the outer periphery of the cold end pipe (200), and the cold end flange (310) is fixed by extrusion through an internal step, thereby realizing connection with a superconducting cavity or a superconducting solenoid in a superconducting acceleration module. Similarly, the hot end flange (500) further includes a hot end flange (510) and a hot end flange body (520), the hot end flange (510) is connected to the hot end compound pipe (400) and extends to the outside of the hot end compound pipe (400), the hot end flange body (520) is sleeved on the hot end compound pipe (400) or the outer periphery of the innermost sub-pipe of the hot end compound pipe (400), and the hot end flange (510) is fixed by extrusion through the internal step, thereby realizing the connection with the room temperature vacuum chamber. The size and specification of the flange are not limited, the metal sealing slip-on flange can ensure that the beam in the compound insulation bellows can operate in a high vacuum environment, and the design of the slip-on flange can ensure the reliability and convenience of on-site installation.

[0045] In one embodiment, the compound insulation bellows further comprises: a heat-isolating connecting ring (600), the heat-isolating connecting ring (600) being a thin-walled ring, the heat-isolating connecting ring (600) being connected to the second end of the bellows (100), and the heat-isolating connecting ring (600) being used to connect a cooling belt of a superconducting acceleration module.

[0046] The heat-isolating connecting ring (600) is located between the bellows (100) and the hot end compound pipe (400). For example, the heat-isolating connecting ring (600) is arranged around the outer wall of the hot end joint (120) and can be welded to the hot end joint (120). The heat-isolating connecting ring (600) is provided with 4-8 bolt connection holes for connecting the cold conducting belt, which plays a role of heat cutoff and reduces the amount of cold introduced from the hot end to the cold end. The heat-isolating connecting ring (600) can be made of a material with good thermal conductivity, such as copper.

[0047] The cooling belt can be a liquid nitrogen cold screen. In one embodiment, the superconducting acceleration module includes a vacuum cylinder, which can be made of stainless steel. The vacuum cylinder includes an inner cavity. A liquid nitrogen cold screen can be set on the inner side of the vacuum cylinder. The cold screen is generally a copper screen or an aluminum screen, on which a cold screen tube filled with liquid nitrogen is set. The cold screen tube is coiled, and the liquid nitrogen cold screen circulates liquid nitrogen to provide cooling for the inner cavity, thereby maintaining the low temperature environment in the inner cavity. The thermal isolation connection ring (600) can be connected to the liquid nitrogen cold screen in the superconducting acceleration module to achieve cooling, and the temperature is about 80K. The aforementioned cold end flange (300) is connected to the superconducting cavity or superconducting solenoid in the superconducting acceleration module, and the temperature is 2K or 4K. The hot end flange (500) is connected to the room temperature end, that is, the room temperature vacuum chamber, and the temperature is about 300K. The thermal isolation connection ring (600) can achieve the ability to conduct 300K-80K heat to the 80K liquid nitrogen cold screen. The effective heat transfer length of the bellows (100) is longer than that of the hot end compound pipe (400). Setting the bellows (100) in a temperature zone below 80K is beneficial to reducing the 2K or 4K heat leakage at the cold end flange (300), thereby improving the refrigeration efficiency of the system.

[0048] The heat-isolating connecting ring (600) plays a role of heat cutoff, optimizes the temperature gradient along the axial direction of the bellows (100), and further reduces the heat leakage introduced from the room temperature to the low-temperature element through the cold end flange (300).

[0049] On the other hand, the present invention also provides a superconducting accelerating module, comprising any of the aforementioned compound insulation bellows.

[0050] The cold end flange (300) of the compound thermal insulation bellows is connected to the superconducting cavity or superconducting solenoid in the superconducting acceleration module, and the hot end flange (500) is connected to the room temperature end, that is, the room temperature vacuum chamber. The superconducting acceleration module includes any of the above compound thermal insulation bellows, including any of the above compound thermal insulation bellows, and the advantages of the compound thermal insulation bellows are not repeated here.

[0051] In an embodiment in which the superconducting acceleration module includes the aforementioned liquid nitrogen cold shield and the compound insulation bellows includes a heat-isolating connecting ring (600), the heat-isolating connecting ring (600) is connected to the liquid nitrogen cold shield.

[0052] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A composite insulation bellows for a superconducting acceleration module, characterized in that: include: Bellows (100), cold end pipe (200), cold end flange (300), hot end compound pipe (400) and hot end flange (500); The cold end pipe (200) is connected to a first end of the bellows (100), the hot end compound pipe (400) is connected to a second end of the bellows (100) away from the first end, the cold end flange (300) is connected to an end of the cold end pipe (200) away from the bellows (100), and the hot end flange (500) is connected to an end of the hot end compound pipe (400) away from the bellows (100); The hot end composite pipe (400) comprises at least two sub-pipes, the at least two sub-pipes are sequentially sleeved toward the outer layer, and adjacent sub-pipes are arranged at intervals, and the two ends of any current sub-pipe located in the middle are respectively connected to the sub-pipe located at the outer layer of the current sub-pipe and the sub-pipe located at the inner layer of the current sub-pipe; The bellows (100) is connected to the end of the sub-tube located at the outermost side, and the hot end flange (500) is connected to the end of the sub-tube located at the innermost side; Part of the ends of the sub-connecting pipes extend into the corrugated pipe (100).

2. The composite insulation bellows for superconducting acceleration module according to claim 1, characterized in that: The hot end composite pipe (400) comprises a first sub-pipe (410), a second sub-pipe (420) and a third sub-pipe (430); the second sub-pipe (420) is sleeved on the outer circumference of the first sub-pipe (410), and a gap is provided between the second sub-pipe (420) and the first sub-pipe (410); the third sub-pipe (430) is sleeved on the outer circumference of the second sub-pipe (420), and a gap is provided between the third sub-pipe (430) and the second sub-pipe (420); Two ends of the second sub-duct (420) are respectively connected to the first end of the first sub-duct (410) and the first end of the third sub-duct (430); the second end of the first sub-duct (410) is connected to the hot end flange (500); and the second end of the third sub-duct (430) is connected to the bellows (100); The first sub-connecting pipe (410) and the second sub-connecting pipe (420) extend from the first end of the first sub-connecting pipe (410) into the corrugated tube (100).

3. The composite insulation bellows for superconducting acceleration module according to claim 1, characterized in that: The bellows (100) comprises a tube body (110) and a hot end joint (120), wherein the hot end joint (120) is connected to the tube body (110), and the hot end joint (120) is located at the second end of the bellows (100); The minimum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end flange (500); the hot end compound pipe (400) is connected to the hot end joint (120); and the maximum inner diameter of the hot end compound pipe (400) is the same as the inner diameter of the hot end joint (120).

4. The composite insulation bellows for a superconducting acceleration module according to claim 1, characterized in that: The cold end pipe (200) and the cold end flange (300) have the same inner diameter.

5. The composite insulation bellows for a superconducting acceleration module according to claim 1, characterized in that: The bellows (100) is a thin-walled welded bellows, and the inner diameter of the bellows (100) is greater than the inner diameter of the cold end pipe (200).

6. The composite insulation bellows for a superconducting acceleration module according to claim 1, characterized in that: The cold end flange (300) and the hot end flange (500) are both slip-on flanges.

7. The composite insulation bellows for a superconducting acceleration module according to claim 1, characterized in that: The compound insulation bellows also includes: A thermal isolation connecting ring (600) is a thin-walled ring, the thermal isolation connecting ring (600) is connected to the second end of the bellows (100), and the thermal isolation connecting ring (600) is used to connect the cooling belt of the superconducting acceleration module.

8. A superconducting acceleration module, characterized in that: The composite thermal insulation corrugated pipe comprises the composite thermal insulation corrugated pipe according to any one of claims 1 to 7.

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