Superconducting magnet horizontal test thermostat

Abstract

This disclosure provides a thermostat for horizontal testing of superconducting magnets, applicable to various sizes of curved deflection superconducting magnets, comprising: an outer Dewar for providing a vacuum testing environment for the curved deflection superconducting magnet; a cooling screen for reducing radiative heat leakage from the curved deflection superconducting magnet; a liquid helium service component, located above the outer Dewar for introducing liquid helium into the outer Dewar in liquid helium immersion cooling mode to cool the curved deflection superconducting magnet; a refrigerator, located above the outer Dewar for providing cooling to the interior of the outer Dewar in conduction cooling mode, or maintaining the liquid helium temperature inside the outer Dewar in liquid helium immersion cooling mode; a temperature-controlled curved tube, traversing the interior of the outer Dewar and passing through the curved deflection superconducting magnet, for performing horizontal testing on the curved deflection superconducting magnet; and a support component, connected to the outer Dewar for adjusting the attitude of the outer Dewar and the curved deflection superconducting magnet.

Description

Technical Field

[0001] This disclosure relates to the field of cryogenic thermostat technology, and more specifically, to a superconducting magnet horizontal testing thermostat. Background Technology

[0002] Currently, medical compact synchrotrons utilize arc-shaped deflecting superconducting magnets on the rotating Gantry and synchrotron loops. Before being put into operation, these superconducting magnets require vertical and horizontal testing. Vertical testing primarily uses a vertical testing Dewar for cryogenic immersion in liquid helium. While this allows for excitation training, it cannot simulate the normal operating conditions of a superconducting magnet. After completing the vertical excitation training, horizontal testing is necessary to simulate the normal operating conditions of the superconducting magnet and obtain relevant data on magnetic field quality (such as integrated magnetic field and magnetic field uniformity).

[0003] For solenoid-type, straight diode / multipole superconducting magnets, horizontal testing can be performed directly through a direct-temperature orifice tube in a cryostat. However, for curved deflection superconducting magnets, a cryogenic Dewar suitable for horizontal testing has not yet been developed. Curved deflection superconducting magnets on rotating Gantry cranes are cooled by conduction, while those on synchrotron rings are cooled by liquid helium immersion. Due to the different cooling methods for these two types of magnets, two different sizes of cryogenic Dewars are typically required for horizontal testing. Furthermore, because the bending radius, deflection angle, and inner and outer diameters of the skeleton vary for curved deflection superconducting magnets, a single testing device usually cannot meet the testing requirements for curved deflection superconducting magnets of different sizes. Summary of the Invention

[0004] In view of this, the present disclosure provides a superconducting magnet horizontal testing thermostat.

[0005] One aspect of this disclosure provides a thermostat for horizontal testing of superconducting magnets, applicable to arc-shaped deflection superconducting magnets of various sizes, comprising: an outer Dewar for providing a vacuum testing environment for the arc-shaped deflection superconducting magnet, reducing radiative heat leakage; a liquid helium service component, disposed above the outer Dewar for introducing liquid helium into the outer Dewar in liquid helium immersion cooling mode to cool the arc-shaped deflection superconducting magnet; a refrigerator, disposed above the outer Dewar for providing cooling to the interior of the outer Dewar in conduction cooling mode, or maintaining the liquid helium temperature inside the outer Dewar in liquid helium immersion cooling mode; a temperature-controlled curved tube, traversing the interior of the outer Dewar and passing through the arc-shaped deflection superconducting magnet, for performing horizontal testing on the arc-shaped deflection superconducting magnet; and a support component connected to the outer Dewar for adjusting the attitude of the outer Dewar and the arc-shaped deflection superconducting magnet.

[0006] According to an embodiment of this disclosure, the refrigerator includes: a primary cold head and a secondary cold head for providing cooling to the outer Dewar; the primary cold head is used to cool a primary cold-conducting plate, which conducts cooling to the cold shield; the secondary cold head is used to cool a secondary cold-conducting plate; the primary and secondary cold-conducting plates are disposed inside the outer Dewar; the cold shield is disposed inside the outer Dewar and connected to the primary cold-conducting plate; the secondary cold-conducting plate is located closer to the arc-shaped deflection superconducting magnet than the primary cold-conducting plate, and is connected to the arc-shaped deflection superconducting magnet via a copper braided strip, for cooling the arc-shaped deflection superconducting magnet.

[0007] According to embodiments of this disclosure, in the liquid helium immersion cooling mode, it further includes: a magnetic helium tank and a liquid helium inlet pipe; the magnetic helium tank is disposed inside the outer Dewar and is used to contain liquid helium input by the liquid helium service component through the liquid helium inlet pipe to immerse and cool the arc-shaped deflection superconducting magnet.

[0008] According to embodiments of this disclosure, it further includes: an eccentric flange disposed at one end of the outer Dewar, connected to the temperature hole bend, used to adjust the position of the temperature hole bend, and to seal the outer Dewar.

[0009] According to embodiments of this disclosure, the dimensions, bending radius, and deflection angle of the temperature-perforated bend are matched with the arc-shaped deflection superconducting magnet.

[0010] According to an embodiment of this disclosure, the support assembly includes: a magnet-adjustable support base disposed inside the outer Dewar for supporting the arc-shaped deflection superconducting magnet and adjusting the position of the arc-shaped deflection superconducting magnet so that the arc-shaped deflection superconducting magnet matches the axis of the temperature-perforated bend tube.

[0011] According to an embodiment of this disclosure, the support assembly further includes: a highly insulating support structure disposed below the outer Dewar and connected to the adjustable support base of the magnet, used to reduce heat leakage conducted by the arc-shaped deflection superconducting magnet.

[0012] According to an embodiment of this disclosure, the support assembly further includes: a three-dimensional adjustable support base connected below the high thermal insulation support structure for supporting the outer Dewar and adjusting the overall posture of the outer Dewar.

[0013] According to embodiments of this disclosure, the primary and secondary cold-conducting plates are made of copper.

[0014] According to an embodiment of this disclosure, the temperature-controlled bend is made of 316L stainless steel.

[0015] This disclosure provides a horizontal testing thermostat for conducting and immersion cooling of various sizes of arc-shaped deflection superconducting magnets. This horizontal testing thermostat can be adapted to superconducting magnets with two different cooling methods: conduction cooling and liquid helium immersion. It can also perform horizontal testing on arc-shaped deflection superconducting magnets with different deflection radii and deflection angles. Attached Figure Description

[0016] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0017] Figure 1 A schematic diagram of the external structure of a superconducting magnet horizontal test thermostat to which this disclosure can be applied is shown.

[0018] Figure 2 A schematic half-section view of a superconducting magnet horizontal test thermostat is shown according to an embodiment of the present disclosure.

[0019] Explanation of reference numerals in the attached figures:

[0020] 1-External Dewar, 2-Refrigerator, 3-Current Lead, 4-Superconducting Magnet, 5-Three-dimensional Adjustable Support Base, 6-Magnet Adjustable Support Base, 7-Temperature Hole Bend, 8-Cold Screen, 9-High Insulation Support Structure, 10-Eccentric Flange, 11-Liquid Helium Service Component, 12-Secondary Cold Conducting Plate, 13-Primary Cold Conducting Plate. Detailed Implementation

[0021] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0022] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0023] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0024] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

[0025] like Figure 1 and Figure 2 As shown in the embodiments of this disclosure, a superconducting magnet horizontal testing thermostat can be applied to various sizes of arc-shaped deflection superconducting magnets 4. It includes: an outer Dewar 1, used to provide a vacuum testing environment for the arc-shaped deflection superconducting magnet 4, reducing radiative heat leakage; a liquid helium service component 11, located above the outer Dewar 1, used to input liquid helium into the outer Dewar 1 in liquid helium immersion cooling mode to cool the arc-shaped deflection superconducting magnet 4; a refrigerator 2, located above the outer Dewar 1, used to provide cooling to the interior of the outer Dewar 1 in conduction cooling mode, or to maintain the liquid helium temperature inside the outer Dewar 1 in liquid helium immersion cooling mode; a temperature-controlled curved pipe 7, traversing the interior of the outer Dewar 1 and passing through the arc-shaped deflection superconducting magnet 4, used for horizontal testing of the arc-shaped deflection superconducting magnet 4; and a support component, connected to the outer Dewar 1, used to adjust the attitude of the outer Dewar 1 and the arc-shaped deflection superconducting magnet 4.

[0026] In this embodiment, the refrigerator 2 is a GM refrigerator 2, including a primary cold head and a secondary cold head, used to provide cooling to the outer Dewar 1. The primary cold head cools the primary cooling plate 13, which conducts cooling to the cold shield 8. The secondary cold head cools the secondary cooling plate 12. The primary and secondary cooling plates 13 and 12 are located inside the outer Dewar 1. The cold shield 8 is located inside the outer Dewar 1 and connected to the primary cooling plate 13. The secondary cooling plate 12 is located closer to the arc-shaped deflection superconducting magnet 4 than the primary cooling plate 13, and is connected to the arc-shaped deflection superconducting magnet 4 via a copper braided strap, used to cool the arc-shaped deflection superconducting magnet 4.

[0027] In this embodiment of the disclosure, in the liquid helium immersion cooling mode, the superconducting magnet 4 horizontal test thermostat, in addition to the liquid helium service component 11, also includes a magnet helium tank and a liquid helium inlet pipe. The magnet helium tank is located inside the outer Dewar 1 and is used to contain liquid helium input by the liquid helium service component 11 through the liquid helium inlet pipe to immerse and cool the arc-shaped deflection superconducting magnet 4, providing cooling for the arc-shaped superconducting magnet 4.

[0028] The superconducting magnet horizontal testing thermostat also includes: an eccentric flange 10, located at one end of the outer Dewar 1, connected to a temperature orifice bend 7, used to adjust the position of the temperature orifice bend 7, and to seal the outer Dewar 1. The dimensions, bending radius, and deflection angle of the temperature orifice bend 7 are matched to the arc-shaped deflecting superconducting magnet 4. By modifying the bend dimensions, arc-shaped deflecting superconducting magnets 4 with different bending radii and deflection angles can be matched, meeting the testing requirements for arc-shaped deflecting superconducting magnets 4 with bending radii of 800-2500 mm and deflection angles of 25-60°.

[0029] In this embodiment, the support assembly includes a magnet-adjustable support base 6. The magnet-adjustable support base 6 is disposed inside the outer Dewar 1 to support the arc-shaped deflection superconducting magnet 4 and adjust its position so that it matches the axis of the arc-shaped deflection superconducting magnet 4 with the axis of the temperature-controlled bend tube 7. The support assembly also includes a highly insulating support structure 9 disposed below the outer Dewar 1 and connected to the magnet-adjustable support base 6 to reduce heat conduction leakage from the arc-shaped deflection superconducting magnet 4. The support assembly further includes a three-dimensional adjustable support base 5 connected below the highly insulating support structure 9 to support the outer Dewar 1 and adjust its overall posture.

[0030] According to the superconducting magnet horizontal test thermostat provided in this embodiment, the entire outer Dewar 1 is supported and its position adjusted by a three-dimensional adjustable support. The radiation cooling screen 8 and multi-layer insulation materials reduce the low-temperature heat leakage of the superconducting magnet. The magnet is fixed on the adjustable support base and can be adjusted and positioned together with the adjustment base so that the central axis of the superconducting magnet 4 matches the axis of the temperature orifice bend 7. It is supported by a high-insulation support structure 9. The top includes a GM refrigerator 2 as a conduction cooling and liquid helium "zero" evaporation low-temperature cold source, and is equipped with a liquid helium service component 11 for liquid helium input. In the middle, an eccentric adjustable flange and an arc-shaped temperature orifice tube are used to isolate the vacuum and serve as a magnetic field quality test channel. When conducting cooling of the superconducting magnet 4, the GM refrigerator 2's secondary cold head cools the secondary cold-conducting plate. The cold-conducting plate transfers cold energy to the magnet through copper braided straps, thus conducting cooling of the magnet. When liquid helium is immersed in cooling the superconducting magnet 4, liquid helium is first introduced into the magnet's helium tank (in the liquid helium immersion cooling method, the magnet has a stainless steel structure that seals the liquid helium outside; this structure is absent in the conduction cooling method) through the top service component 11 via a liquid helium inlet pipe. Then, the liquid helium inlet pipe is removed, and the GM refrigerator 2 maintains "zero" evaporation of liquid helium. The GM refrigerator 2's primary cold head cools the primary cold-conducting plate 13, conducting cooling of the entire cold shield 8 cylinder, creating a cold shield 8 with a temperature better than 80K, reducing system heat leakage. During the cooling process, the horizontal test thermostat can connect the cold head and the cooling plate with a soft copper braided strap to prevent vibration from affecting the superconducting magnet 4. The end eccentric flange 10 can provide radial vacuum sealing, and the position of the temperature orifice bend 7 can be adjusted by adjusting the end bolts. The bellows can be matched to adjust the angle. By modifying the size of the arc bend, it can match the arc deflection superconducting magnet 4 with different bending radii and deflection angles, which can meet the testing requirements of arc deflection superconducting magnet 4 with bending radii of 800-2500mm and deflection angles of 25-60°. At the same time, the base plate height adjustment device can adapt to the testing requirements of arc deflection superconducting magnet 4 with a skeleton diameter of 100-500mm. One horizontal test thermostat is compatible with the cooling requirements of both conductive cooling and liquid helium immersion cooling magnets, which greatly saves costs and broadens the application requirements.

[0031] The cooling copper plate and copper braided strip are made of copper with high thermal conductivity at low temperatures and high RRR. The test bend is made of 316L stainless steel with low magnetic permeability to reduce the influence of magnetization effect during the excitation process on the magnetic field measurement results.

[0032] The three-dimensional adjustable support base, GM refrigerator 2, current lead 3 (for providing power to refrigerator 2 and liquid helium service component 11), wall-penetrating component, liquid helium service component 11, and eccentric flange 10 are placed on the outer Dewar 1 of the thermostat. The environment outside the outer Dewar 1 is normal temperature and pressure. The cold conduction plate, copper braided strip, adjustable magnetic support base 6, superconducting magnet 4, and cold screen 8 are all placed in the outer Dewar 1 of the thermostat. The environment inside the outer Dewar 1 is a vacuum environment. GM refrigerator 2 conducts cooling to superconducting magnet 4 through copper braided strip connected to the cold head or performs "zero" evaporation cooling by liquid helium immersion.

[0033] The superconducting magnet horizontal test thermostat provided in this embodiment can avoid the influence of vibrating components on the superconducting magnet 4 during the cooling process; its end eccentric flange 10 can adjust the position of the temperature hole bend 7 to match the magnet axis; the copper cold conduction plate and copper braided strip with high RRR value and high thermal conductivity at low temperature improve the thermal conductivity and improve the temperature uniformity of the superconducting magnet 4; it can be used for horizontal testing of arc deflection superconducting magnet 4 with different bending radii, different deflection angles and different skeleton diameters; a single horizontal test thermostat meets the testing requirements of arc deflection superconducting magnet 4 for both conductive cooling and liquid helium immersion cooling.

Claims

1. A superconducting magnet horizontal testing thermostat, applicable to arc-shaped deflection superconducting magnets of various sizes (4), comprising: An external Dewar (1) is used to provide a vacuum testing environment for the arc-shaped deflection superconducting magnet (4), and a cold screen (8) reduces the radiative heat leakage of the arc-shaped deflection superconducting magnet (4). A liquid helium service component (11) is located above the outer Dewar (1) and is used to input liquid helium into the outer Dewar (1) in liquid helium immersion cooling mode to cool the arc deflection superconducting magnet (4). A refrigeration unit (2) is disposed above the outer Dewar (1) for providing cooling to the interior of the outer Dewar (1) in conduction cooling mode, or for maintaining the liquid helium temperature inside the outer Dewar (1) in liquid helium immersion cooling mode. A temperature-controlled bent tube (7) traverses the interior of the outer Dewar (1) and passes through the arc-shaped deflection superconducting magnet (4) to perform a horizontal test on the arc-shaped deflection superconducting magnet (4); A support assembly is connected to the outer Dewar (1) and is used to adjust the attitude of the outer Dewar (1) and the arc-shaped deflection superconducting magnet (4).

2. The superconducting magnet horizontal testing thermostat according to claim 1, wherein, The refrigeration unit (2) includes: The primary and secondary cold heads are used to provide cooling for the external Dewar (1); The primary cold head is used to cool the primary cold plate (13), and the primary cold plate (13) conducts the cooling of the cold screen (8). The secondary cold head is used to cool the secondary cold plate (12). The primary cooling plate (13) and the secondary cooling plate (12) are disposed inside the outer Dewar (1); The cold shield (8) is located inside the outer Dewar (1) and is connected to the primary cold-conducting plate (13). The secondary cooling plate (12) is located closer to the arc-shaped deflection superconducting magnet (4) than the primary cooling plate (13), and is connected to the arc-shaped deflection superconducting magnet (4) by a copper braided strip, for cooling the arc-shaped deflection superconducting magnet (4).

3. The superconducting magnet horizontal testing thermostat according to claim 1, wherein, The liquid helium immersion cooling mode also includes: Magnetic helium tank and liquid helium infusion tubing; The magnet helium tank is located inside the outer Dewar (1) and is used to contain liquid helium supplied by the liquid helium service component (11) through the liquid helium infusion tube to soak and cool the arc deflection superconducting magnet (4).

4. The superconducting magnet horizontal testing thermostat according to claim 1, wherein, Also includes: An eccentric flange (10) is provided at one end of the outer Dewar (1) and connected to the temperature hole bend (7) for adjusting the position of the temperature hole bend (7) and sealing the outer Dewar (1).

5. The superconducting magnet horizontal testing thermostat according to claim 1, wherein, The dimensions, bending radius, and deflection angle of the temperature-perforated bend (7) are matched with those of the arc-shaped deflection superconducting magnet (4).

6. The superconducting magnet horizontal testing thermostat according to claim 1, wherein, The support components include: The adjustable support base (6) is located inside the outer Dewar (1) to support the arc-shaped deflection superconducting magnet (4) and adjust the position of the arc-shaped deflection superconducting magnet (4) so ​​that the arc-shaped deflection superconducting magnet (4) matches the axis of the temperature hole bend (7).

7. The superconducting magnet horizontal testing thermostat according to claim 6, wherein, The support components also include: A high-insulation support structure (9) is located below the outer Dewar (1) and connected to the adjustable support base (6) of the magnet, which is used to reduce heat leakage conducted by the arc-shaped deflection superconducting magnet (4).

8. The superconducting magnet horizontal testing thermostat according to claim 7, wherein, The support components also include: A three-dimensional adjustable support base (5) is connected below the high thermal insulation support structure (9) to support the outer Dewar (1) and adjust the overall posture of the outer Dewar (1).

9. The superconducting magnet horizontal testing thermostat according to claim 2, wherein, The primary cooling plate (13) and the secondary cooling plate (12) are made of copper.

10. The superconducting magnet horizontal testing thermostat according to claim 1, wherein, The temperature-controlled bend (7) is made of 316L stainless steel.

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