CRYOSTAT FOR SUPERCONDUCTING MAGNET SYSTEM
20170268726 · 2017-09-21
Assignee
Inventors
Cpc classification
F17C2270/0527
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F25B19/005
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C3/085
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2203/015
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C13/006
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C2270/0536
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F17C13/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F17C3/08
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A cryostat for a superconducting magnet system is provided. The cryostat may include an outer vessel and an inner vessel suspended within the outer vessel. A space may be defined by the outer vessel and the inner vessel. The cryostat may include multiple first support elements and one or more second support elements. The strength of the first supporting element may be larger than that of the second support elements. The inner vessel and the outer vessel may be connected by two opposite ends of a first support element and two opposite ends of a second support element, respectively. The number of the first support elements in the lower part of the space is different from the number of the first support elements in the upper part of the space.
Claims
1. A cryostat comprising: an outer vessel; an inner vessel suspended within the outer vessel; a space defined by the inner vessel and the outer vessel, the space having an upper part and a lower part; a plurality of first support elements comprising a first number of the first support elements located in the upper part of the space and a second number of the first support elements located in the lower part, each of the plurality of first support elements having a first strength; and a second support element having a second strength, wherein the first strength of at least one of the plurality of first support elements is different from the second strength of the second support element, the inner vessel and the outer vessel are connected by two opposite ends of a first support element of the plurality of first support element, the inner vessel and the outer vessel are connected by and two opposite ends of the second support element, and the first number is different from the second number.
2. The cryostat of claim 1, wherein the second number is four and the first number is at least two.
3. The cryostat of claim 1, comprising two second support elements.
4. The cryostat of claim 1, wherein the plurality of first support elements comprise a high-strength alloy or a composite.
5. The cryostat of claim 4, wherein the composite comprises glass fibers, carbon fibers, or kevlar.
6. The cryostat of claim 1, wherein the first support elements comprise rods or bands.
7. The cryostat of claim 1, wherein the second support element is a rod.
8. The cryostat of claim 1, wherein the first strength of at least one of the plurality of first support elements is larger than the second strength of the second support element.
9. The cryostat of claim 1, wherein the first strength or the second strength is a tensile strength or a compressive strength.
10. The cryostat of claim 1, wherein the cross sectional area of at least one of the plurality of first support elements is larger than the cross sectional area of the second support element.
11. The cryostat of claim 1, wherein the length of the first support elements is 300˜800 mm, and the cross sectional area of the first support elements is 50˜300 mm.sup.2.
12. The cryostat of claim 1, wherein the length of the second support element is 200˜800 mm, and the cross sectional area of the second support element is 10˜100 mm.sup.2.
13. A cryostat comprising: an outer vessel; an inner vessel, suspended within the outer vessel; a space defined by the inner vessel and the outer vessel, the space having an upper part and a lower part; a plurality of first supports element; and a plurality of second support elements, wherein, the strength of at least one of the first support elements is larger than the strength of at least one of the second support elements; the inner vessel and the outer vessel are connected by two opposite ends of a first support element of the plurality of first support elements, the inner vessel and the outer vessel are connected by two opposite ends of a second support element of the plurality of second support elements, and the number of the first support elements in the lower part of the space is larger than the number of the first support elements in the upper part of the space or the number of the first support elements in the upper part of the space is larger than the number of the first support elements in the lower part of the space.
14. The cryostat of claim 13, wherein the first support elements are symmetrically disposed with respect to a first vertical datum plane through the center of the inner vessel.
15. The cryostat of claim 14, wherein the first support elements in the upper part of the space are placed on the first vertical datum plane through the center of the inner vessel.
16. The cryostat of claim 14, wherein the second support elements are symmetrically disposed with respect to the first vertical datum plane through the center of the inner vessel.
17. The cryostat of claim 13, wherein the first support elements are symmetrically disposed with respect to a second vertical datum plane through the center of the inner vessel.
18. The cryostat of claim 17, wherein the second support elements are placed in the second vertical datum plane through the center of the inner vessel.
19. The cryostat of claim 13, wherein the first support elements in the upper part of the space and the first support elements in the lower part of the space are asymmetrically arranged about a horizontal datum plane through the center of the inner vessel.
20. A cryostat comprising: an outer vessel; an inner vessel suspended within the outer vessel; a space defined by the inner vessel and the outer vessel, the space having an upper part and a lower part; a plurality of first support elements comprising a first number of the first support elements located in the upper part of the space and a second number of the first support elements located in the lower part, each of the plurality of first support elements having a first strength; and a second support element having a second strength, wherein the first strength of at least one of the plurality of first support elements is larger than the second strength of the second support element, the inner vessel and the outer vessel are connected by two opposite ends of a first support element of the plurality of first support element, the inner vessel and the outer vessel are connected by and two opposite ends of the second support element, the first number is different from the second number, the angle between the second support element and a horizontal datum plane is smaller than the angle between at least one of the plurality of first support elements and the horizontal datum plane, and the angle between at least one of the plurality of first support element in the upper part of the space and a vertical datum plane is smaller than the angle between the second support element and the vertical datum plane, wherein the vertical datum plane is perpendicular to an axis of the inner vessel.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The present disclosure is further described in terms of exemplary embodiments. These exemplary embodiments are described in detail with reference to the drawings. These embodiments are non-limiting exemplary embodiments, in which like reference numerals represent similar structures throughout the several views of the drawings, and wherein:
[0026]
[0027]
[0028]
[0029]
[0030]
[0031]
[0032]
[0033]
DETAILED DESCRIPTION
[0034] In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant disclosure. However, it should be apparent to those skilled in the art that the present disclosure may be practiced without such details. In other instances, well known methods, procedures, systems, components, and/or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present disclosure. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. Thus, the present disclosure is not limited to the embodiments shown, but to be accorded the widest scope consistent with the claims.
[0035] It will be understood that the term “system,” “engine,” “unit,” “module,” and/or “block” used herein are one method to distinguish different components, elements, parts, section or assembly of different level in ascending order. However, the terms may be displaced by other expression if they may achieve the same purpose.
[0036] It will be understood that when a unit, engine, module or block is referred to as being “on,” “connected to,” or “coupled to” another unit, engine, module, or block, it may be directly on, connected or coupled to, or communicate with the other unit, engine, module, or block, or an intervening unit, engine, module, or block may be present, unless the context clearly indicates otherwise. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
[0037] The terminology used herein is for the purposes of describing particular examples and embodiments only, and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “include,” and/or “comprise,” when used in this disclosure, specify the presence of integers, devices, behaviors, stated features, steps, elements, operations, and/or components, but do not exclude the presence or addition of one or more other integers, devices, behaviors, features, steps, elements, operations, components, and/or groups thereof
[0038]
[0039] In some embodiments, the cryostat may include one or more first support elements 160/170. In some embodiments, the cryostat may include one or more second support elements 180. As used herein, the first support elements 160 may refer to the first support elements in the upper part of the space 190, and the first support elements 170 may refer to the first support elements in the lower part of the space 190. As used herein, the upper part of the space 190 may refer to the portion of the space 190 that is with respect to the direction in which the force may be largest. As used herein, the lower part of the space 190 may refer to the portion of the space 190 that is with respect to the direction in which the force may be smallest. The locations of the first support elements and/or the second support elements may include but are not limited to the upper and/or lower part of the space. In some embodiments, the locations may be adjusted to the right and/or left part according to the structure and/or the directions of forces. It is understood that the upper part of the space 190 and the lower part of the space 190 may be used for convenience and illustration purposes, and are not intended to indicate that when the cryostat is installed in an MM system (or an superconducting magnet system) or when the MRI system (or an superconducting magnet system) is in operation, the upper part is above the lower part. An exemplary cryostat, as illustrated in
[0040] In some embodiments, a first support element 160/170 may be a strong support element or a weak support element. In some embodiments, a second support element 180 may be a strong support element or a weak support element. As used herein, a strong support element may have a large strength such that it may withstand a large load. In some embodiments, a strong support element may be a band or a rod. In some embodiments, the band and/or rod may be made of fiber reinforced composite material. In some embodiments, the band and/or rod may be made of alloy. In some embodiments, an alloyed rod may be with high strength and large cross sectional area. For instance, a strong support element may be a fiber reinforced plastic (FRP) band. The carrying capacity of a FRP band may be 10˜20 tons. The cross sectional area of a strong support element (e.g., a FRP rod) may be at least 10 square millimeters, or at least 20 square millimeters, or at least 30 square millimeters, or at least 40 square millimeters, or at least 50 square millimeters. A weak support element may be placed at a location where the force may be relatively small. The strength of a weak support element may be small. In some embodiments, a weak support element may be a rod with a small cross sectional area. In some embodiments, a weak support element may be made of a same material as a strong support element. In some embodiments, a weak support element may be made of a material different from the material of a strong support element. For instance, the rods may be made of stainless steel. The carrying capacity of a weak support element (e.g., a stainless steel rod) may be 1˜3 tons. The cross sectional area of a weak support element (e.g., a stainless steel rod) may be smaller than 50 square millimeters, or smaller than 40 square millimeters, or smaller than 30 square millimeters, or smaller than 20 square millimeters.
[0041] In some embodiments, both the first support elements 160 in the upper part of the space and the first support elements 170 in the lower part of the space may be strong support elements. In some embodiments, the first support elements 160 and the first support elements 170 may be a same kind of strong support elements. As used herein, two support elements of a same kind may indicate that the support elements are the same in terms of material, shape, and the cross sectional area. In some embodiments, the first support elements 160 in the upper part of the space and the first support elements 170 in the lower part of the space may be different kinds of strong support elements. The first support elements 160 in the upper part of the space and the first support elements 170 in the lower part of the space may withstand different loads because of some factors, including, e.g., spatial positions. In some embodiments, the first support elements 160 in the upper part of the space and the first support elements 170 in the lower part of the space may be made of different materials. In some embodiments, the first support elements 160 in the upper part of the space and the first support elements 170 in the lower part of the space may be with different shapes and/or cross sectional areas. In some embodiments, the first support elements 160 and/or 170 may be weak support elements. In some embodiments, the second support elements 180 may be weak support elements. In some embodiments, the second support elements 180 may be strong support elements. Merely by way of example, in some embodiments, the first support elements 160 and/or 170 may be strong support elements, and the second support elements 180 may be strong support elements. The first support elements 160 in the upper part of the space, the first support elements 170 in the lower part of the space, and the second support elements 180 may be a same kind of strong support elements or different kinds of strong support elements. In some embodiments, the first support elements 160 and/or 170 may be strong support elements, and the second support elements 180 may be week support elements. The first support elements 160 in the upper part of the space and the first support elements 170 in the lower part of the space may be a same kind of strong support elements or different kinds of strong support elements. In some embodiments, the first support elements 160 and/or 170 may be weak support elements, and the second support elements 180 may be week support elements. The first support elements 160 in the upper part of the space, the first support elements 170 in the lower part of the space, and the second support elements 180 may be a same kind of weak support elements or different kinds of weak support elements.
[0042]
[0043]
[0044] In some embodiments, the second support elements 180 may be placed between planes defined by the corresponding ends of the first elements 160 in the upper part of the space 190 or may be placed between the planes defined by the corresponding ends of the first elements 170 in the lower part of the space 190. In some embodiments, the second support elements 180 may be placed on the YZ datum plane and may be symmetrical or asymmetrical with respect to the XY datum plane. The angle (see, e.g., the angle din
[0045] In some embodiments, a support element, e.g., a first support element 160/170, or a second support element 180, may be pre-tensioned to prevent slacking during the cooling process and/or transport.
[0046] It should be noted that the above description about the cryostat is merely provided for the purposes of illustration, and not intended to limiting the scope of the present disclosure. For persons having ordinary skills in the art, multiple variations and modifications may be made under the teachings of the present disclosure. For example, the number and positions of the first support elements and second support elements may be arbitrary. In some embodiments, the second support elements 180 may be merely placed in the lower part of the space 190. In some embodiments, the second support elements 180 may be merely placed in the upper part of the space 190. In some embodiments, the second support elements 180 may be placed both in the upper part of the space 190 and the lower part of the space 190. In some embodiments, the first support elements 160/170 may be placed symmetrically or asymmetrically with respect to the plane defined by the second support elements 180. In some embodiments, the strength of the first supporting element 160/170 may be larger than the strength of the second support elements 180. In some embodiments, the strength of the first supporting element 160/170 may be equal to or smaller than the strength of the second support elements 180. In some other embodiments, the angle formed between the a first support element 160 in the upper part of the space and the horizontal XZ datum plane may be same with the angle formed between a first support elements 170 in the lower part of the space and the horizontal XZ datum plane. In some embodiments, the angles may be different according to different spatial positions of the support elements. However, those variations and modifications do not depart from the scope of the present disclosure.
[0047]
[0048] For illustration purposes, the forces of each support element are be set forth in the following description. When the angle between the second support elements 180 and the horizontal XZ datum plane is small, the shifts of the inner vessel 120 in the X direction and/or the Y direction may generate little influence on the forces on the second support elements 180. As a result, the shock loads in the X/Y direction and the rotating loads in the RX/RY direction may mainly be withstood by the first support elements 160 and 170. As shown in
[0049] Merely by way of example, assume: n.sub.a=4, n.sub.b=2, a=b, and F.sub.a0=F.sub.b0=F.sub.0. For brevity, the force generated by the gravity of the inner vessel is referred to as −1 g, where the sign “−” may denote that the force is along the −Y direction.
[0050] a) In some embodiments, when there is no shock load, the first support elements 170 in the lower part of the space 190 and the first support elements 160 in the upper part of the space 190 may withstand the gravity of the inner vessel 120 (i.e., 1 g).
[0051] b) In some embodiments, when the shock load is +5 g in the +Y direction, a resultant load may be +4 g in the +Y direction. In this case, the first support elements 160 may withstand a larger load than the first support elements 170. In some embodiments, the pre-load on the first support elements 170 may be set to a value to essentially entirely offset the force on the first support elements 170, and thus the force on each of the first support elements 160 may be 2 mg/sin(b). The pre-load on the first support elements 160 and 170, F.sub.0, may be set at least as 2 mg/sin(b). As used herein, “essentially,” as in “essentially entirely,” with respect to a parameter or a feature may indicate that the variation is within 2%, or 5%, or 8%, or 10%, or 15% of the parameter or the feature.
[0052] c) In some embodiments, when the shock load is 5 g in the −Y direction, a resultant load may be 6 g in the −Y direction. In this case, the first support elements 170 may withstand a larger load than the first support elements 160. In some embodiments, the pre-load on the first support elements 160 may be set to a value to essentially entirely offset the force on the first support elements 160, and thus, the force on each of the first support elements 170 may be 3 mg/(2 sin(a)). The pre-load on the first support elements 160 and 170, F.sub.0, may be at least 3 mg/(2 sin(a)).
[0053] Because the shock load may be +5 g in the +Y direction, or −5 g in the −Y direction, the pre-load F.sub.0 may be the larger value of 2 mg/sin(b) and 3 mg/(2 sin(a)). If a=b, the pre-load on each of the first support elements 170 and 160 may be 2 mg/sin(a).
[0054] The force or load on a support element may be relevant to a suspension angle corresponding to a support element with respect to a datum plane (e.g., the angle a, the angle b, the angel c, or the angle din
[0055] Based on the description above, when n.sub.b changes from 4 to 2 (i.e., in a traditional vertically symmetrical suspension system as illustrated in
[0056] Similarly, according to the compatibility conditions of deformation of the material mechanics, subject to the shock load in the X/Y directions and the rotating load of the RX/RZ, the force on the strong support elements may increase by a small amount compared with traditional suspension system, e.g., 5%, 10%, 15%, 20%, 25%, 30%, etc.
[0057] In some embodiments, subject to the shock load in the Z direction and/or the rotating load of the RX, the first support elements 160 on the XY datum plane may be not sensitive to the load in the Z direction and the rotation load of the RX. Thus, the second support elements 180 and the first support elements 170 may bear the shock load in the Z direction and the rotating load of the RX.
[0058] In some embodiments, the mounting point connecting a second support element 180 with the inner vessel 120 may be at the axial end of the inner vessel 120 along the Z axis. Fy (shown in
[0059] Even though the second support elements 180 include weak support elements with a small carrying capacity, the force on the second support elements 180 may increase by a certain amount that is within an allowable range with respect to the tension per-applied on them when the shock load in the Z direction and the rotating load in RX may exist. In some embodiments, the force on the second support elements 180 may increase by, for example, about 30%.
[0060] According to some embodiments of the present disclosure, the inner vessel 120 may move and/or rotate when some shock loads and rotating loads appear. Since the stiffness of the support elements may be large, the rotation angle and the displacement of the support elements may be relatively small and the effect may be neglected.
[0061]
[0062] It should be noted that the suspension system applied to the cryostat holding cryogenic medium according to the present disclosure is merely an example. In some embodiments, the arrangement of the support elements may be applicable in other environments in which a low temperature and isolation of thermal may be needed. For example, the arrangement of the support elements may be used to support the shielding layer of the superconducting magnet cryostat.
[0063] It should be noted that the suspension system described above is provided for the purposes of illustration, and not intended to limit the scope of the present disclosure. Apparently for persons having ordinary skills in the art, numerous variations and modifications may be conducted under the teaching of the present disclosure. However, those variations and modifications may not depart the protecting scope of the present disclosure.
[0064] Having thus described the basic concepts, it may be rather apparent to those skilled in the art after reading this detailed disclosure that the foregoing detailed disclosure is intended to be presented by way of example only and is not limiting. Various alterations, improvements, and modifications may occur and are intended to those skilled in the art, though not expressly stated herein. These alterations, improvements, and modifications are intended to be suggested by this disclosure, and are within the spirit and scope of the exemplary embodiments of this disclosure.
[0065] Moreover, certain terminology has been used to describe embodiments of the present disclosure. For example, the terms “one embodiment,” “an embodiment,” and/or “some embodiments” mean that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Therefore, it is emphasized and should be appreciated that two or more references to “an embodiment” or “one embodiment” or “an alternative embodiment” in various portions of this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined as suitable in one or more embodiments of the present disclosure.
[0066] Furthermore, the recited order of processing elements or sequences, or the use of numbers, letters, or other designations therefore, is not intended to limit the claimed processes and methods to any order except as may be specified in the claims. Although the above disclosure discusses through various examples what is currently considered to be a variety of useful embodiments of the disclosure, it is to be understood that such detail is solely for that purpose, and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover modifications and equivalent arrangements that are within the spirit and scope of the disclosed embodiments. For example, although the implementation of various components described above may be embodied in a hardware device, it may also be implemented as a software only solution, e.g., an installation on an existing server or mobile device.
[0067] Similarly, it should be appreciated that in the foregoing description of embodiments of the present disclosure, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure aiding in the understanding of one or more of the various inventive embodiments. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed subject matter requires more features than are expressly recited in each claim. Rather, inventive embodiments lie in less than all features of a single foregoing disclosed embodiment.
[0068] In some embodiments, the numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth, used to describe and claim certain embodiments of the application are to be understood as being modified in some instances by the term “about,” “approximate,” or “substantially.” For example, “about,” “approximate,” or “substantially” may indicate ±20% variation of the value it describes, unless otherwise stated. Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the present disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable.
[0069] Each of the patents, patent applications, publications of patent applications, and other material, such as articles, books, specifications, publications, documents, things, and/or the like, referenced herein is hereby incorporated herein by this reference in its entirety for all purposes, excepting any prosecution file history associated with same, any of same that is inconsistent with or in conflict with the present document, or any of same that may have a limiting affect as to the broadest scope of the claims now or later associated with the present document. By way of example, should there be any inconsistency or conflict between the description, definition, and/or the use of a term associated with any of the incorporated material and that associated with the present document, the description, definition, and/or the use of the term in the present document shall prevail.
[0070] In closing, it is to be understood that the embodiments disclosed herein are illustrative of the principles of the embodiments of the present disclosure. Other modifications that may be employed may be within the scope of the present disclosure. Thus, by way of example, but not of limitation, alternative configurations of the embodiments of the present disclosure may be utilized in accordance with the teachings herein. Accordingly, embodiments of the present disclosure are not limited to that precisely as shown and described.