A superconducting feeder sealing flange structure and a superconducting feeder flange insulation processing method
By adopting a combined structure of superconducting cable, main insulation layer, additional insulation layer, flange and sealing insulation layer in the superconducting feeder device, the problem of insufficient sealing and insulation of radial flange in the superconducting feeder device under low temperature environment is solved, and reliable sealing and insulation of radial flange in the superconducting feeder device under low temperature environment is realized. It is suitable for radial flange structure treatment in low temperature feeder channel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HEFEI INSTITUTE OF PHYSICAL SCIENCE CHINESE ACADEMY OF SCIENCES
- Filing Date
- 2024-01-03
- Publication Date
- 2026-05-19
AI Technical Summary
Existing sealing structures cannot effectively seal and insulate the radial flanges of superconducting feeders in cryogenic environments, resulting in insufficient sealing and insulation of the superconducting feeder system in cryogenic liquid helium environments.
The structure employs a combination of superconducting cable, main insulation layer, additional insulation layer, flange, adhesive, and sealing insulation layer. A reliable sealing structure is formed by wrapping glass fiber wire inside the additional insulation layer with the flange at the contact surface between the additional insulation layer and the main insulation layer.
It achieves reliable sealing and insulation of radial flanges in superconducting feeder devices under low-temperature conditions, ensuring insulation strength and sealing performance, and is suitable for radial flange structure treatment in low-temperature feeder channels.
Smart Images
Figure CN117944292B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of fusion device technology, and in particular to a superconducting feeder sealing flange structure and a superconducting feeder flange insulation treatment method. Background Technology
[0002] Superconducting feeders are crucial components of magnetic confinement fusion devices. The superconducting feeder system provides power, helium cooling, and instrumentation to the magnets, terminating at a coil terminal box outside the cryostat. The cryostat-feed-through (CFT) is a part of the superconducting feeder. A critical step in the manufacturing of the cryostat-feed-through is the radial flange sealing of the main insulation layer. Because the cryostat-feed-through operates in a cryogenic liquid helium environment, it is essential to ensure a tight seal and insulation between the radial stainless steel flange and the insulation layer under cryogenic conditions. Due to the unique characteristics of superconducting feeders and the cryogenic environment, existing sealing structures cannot be directly applied; currently, no suitable sealing structure for superconducting feeders operating in cryogenic environments has been discovered. Summary of the Invention
[0003] The purpose of this invention is to provide a superconducting feeder sealing flange structure and a superconducting feeder flange insulation treatment method. This structure can achieve sealing and insulation of the radial flange in the manufacturing of low-temperature feeder channel components in a superconducting feeder device.
[0004] To achieve the above objectives, the present invention provides a superconducting feeder sealing flange structure, comprising: a superconducting cable, a main insulation layer, an additional winding insulation layer, a flange, adhesive, and a sealing insulation layer; the main insulation layer is wrapped around the outside of the superconducting cable, and the additional winding insulation layer is wrapped around the outside of the main insulation layer; a sleeve is provided on the inner side of the flange, and the flange is fitted onto the outside of the additional winding insulation layer through the sleeve, and the sleeve is connected to the additional winding insulation layer through the adhesive; the sealing insulation layer covers the sleeve and the additional winding insulation layer, and the sealing insulation layer is connected to the main insulation layer.
[0005] Preferably, the main insulation layer comprises, from the inside out, a first pre-impregnated tape half-overlay layer, a pre-impregnated tape and polyimide composite tape half-overlay layer, a second pre-impregnated tape half-overlay layer, a conductive felt layer, and a third pre-impregnated tape half-overlay layer, wherein a wrapping tape is provided between the first pre-impregnated tape half-overlay layer and the pre-impregnated tape and polyimide composite tape half-overlay layer.
[0006] Preferably, the first prepreg tape half-overlay layer has 1 to 2 layers of prepreg tape half-overlay, the prepreg tape and polyimide composite tape half-overlay layer has 6 to 9 layers of prepreg tape and polyimide composite tape half-overlay, the second prepreg tape half-overlay layer has 1 to 2 layers of prepreg tape half-overlay, the conductive felt layer has 1 to 3 layers of conductive felt, and the third prepreg tape half-overlay layer has 2 to 3 layers of prepreg tape half-overlay.
[0007] Preferably, the reinforced insulation layer has 14 to 16 layers of pre-impregnated tape semi-overlapping wrapped from the inside out.
[0008] Preferably, the reinforcing insulation layer forms steps with the main insulation layer at both ends along the length of the superconducting cable.
[0009] Preferably, the outer surface of the reinforcing insulation layer is provided with an external thread, and the inner surface of the sleeve is provided with an internal thread that mates with the external thread.
[0010] Preferably, the sealing insulation layer is an impregnated glass fiber wrapping layer, wherein the impregnated glass fiber wrapping layer is formed by wrapping the sleeve and the additional insulation layer with glass fiber impregnated with low-temperature adhesive.
[0011] The present invention also provides a method for insulating a superconducting feeder flange, which includes the following steps:
[0012] a: The superconducting cable is wrapped sequentially with a first pre-impregnated tape half-layer, a pre-impregnated tape and polyimide composite tape half-layer, a second pre-impregnated tape half-layer, a conductive felt layer, and a third pre-impregnated tape half-layer to complete the wrapping of the main insulation layer; wherein, when the first pre-impregnated tape half-layer is wrapped around the superconducting cable, a wrapping tape is wrapped around the outside of the first pre-impregnated tape half-layer, and then the wrapping tape and the first pre-impregnated tape half-layer are wrapped with a pre-impregnated tape and polyimide composite tape half-layer;
[0013] b: 14 to 16 layers of pre-impregnated tape are wrapped around the surface of the main insulation layer in a semi-overlapping manner, thus forming an additional winding insulation layer on the surface of the main insulation layer; then the additional winding insulation layer and the main insulation layer are heated and cured.
[0014] c: Grind the outer surface of the reinforcing insulation layer until the outer diameter of the reinforcing insulation layer is 63 to 66 mm; then machine the external threads on the outer surface of the reinforcing insulation layer and clean the surface dust.
[0015] d: Machining the flange sleeve to match the internal thread of the external thread on the outer surface of the insulation layer, and cleaning the surface dust;
[0016] e: Apply low-temperature adhesive to the internal threads of the flange and the external threads of the outer surface of the reinforcing insulation layer, and then fit the flange onto the external threads of the outer surface of the reinforcing insulation layer that has been coated with low-temperature adhesive;
[0017] f: The glass fiber impregnated with low-temperature adhesive is wrapped around the outer surface of the reinforcing insulation layer and the outer surface of the flange sleeve, and extended to the outer surface of the main insulation layer to form a sealed insulation layer;
[0018] g: The sealing insulation layer is heated and cured to complete the insulation treatment of the superconducting feeder flange.
[0019] Preferably, in step a, the first prepreg tape half-overlay layer is a single layer of prepreg tape half-overlay, the prepreg tape and polyimide composite tape half-overlay layer is a seven-layer prepreg tape and polyimide composite tape half-overlay, the second prepreg tape half-overlay layer is a single layer of prepreg tape half-overlay, the conductive felt layer has two layers of conductive felt, and the third prepreg tape half-overlay layer is a two-layer prepreg tape half-overlay.
[0020] Preferably, the low-temperature adhesive is an adhesive in which epoxy resin and curing agent are mixed evenly in a mass ratio of 4:1.
[0021] The superconducting feeder sealing flange structure and superconducting feeder flange insulation treatment method provided by this invention have the following advantages: The superconducting feeder sealing flange structure obtained in this embodiment is tightly installed with the flange by adding an insulation layer, and the sealing insulation layer made of glass fiber wire covers the contact surface between the sealing insulation layer and the flange, making the flange seal more reliable. The superconducting feeder sealing flange structure of this embodiment works in a low-temperature environment and is suitable for the insulation treatment of radial flange structures in low-temperature feeder channels (CFT). It has a simple structure, is easy to operate, and can ensure the insulation strength and the sealing performance requirements of the radial flange. After the insulation of the CFT components of the fusion reactor superconducting feeder and the radial flange insulation treatment are completed, it has good application value in the field of radial flange sealing insulation treatment.
[0022] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0023] Figure 1 This is a schematic cross-sectional view of the superconducting feeder flange structure according to an embodiment of the present invention;
[0024] Figure 2 This is a schematic diagram of the state when the tape is partially overlapped and wrapped around the entire loop;
[0025] Figure 3 This is a schematic diagram of the state when the tape is partially overlapped and wrapped twice.
[0026] Figure 4 This is a schematic diagram of the state when the tape is partially overlapped and wrapped three times.
[0027] Figure 5 This is a schematic diagram of the structure of the pre-impregnated tape and the polyimide composite tape in an embodiment of the present invention.
[0028] In the diagram, 1 is the superconducting cable; 2 is the main insulation layer; 3 is the additional winding insulation layer; 4 is the flange; 5 is the sealing insulation layer; 6 is the sleeve; and 7 is the step. Detailed Implementation
[0029] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.
[0030] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this 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. Therefore, they should not be construed as limiting this invention.
[0031] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.
[0032] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.
[0033] Please refer to the following: Figures 1 to 4 The superconducting feeder sealing flange structure provided in the embodiments of the present invention will now be described.
[0034] Reference Figure 1 The superconducting feeder sealing flange structure of this embodiment includes: superconducting cable 1, main insulation layer 2, additional winding insulation layer 3, flange 4, adhesive, and sealing insulation layer;
[0035] The main insulation layer 2 is wrapped around the outside of the superconducting cable 1, serving to insulate the superconducting cable 1 from the outside. The additional insulation layer 3 is wrapped around the outside of the main insulation layer 2. A sleeve 6 is provided on the inner side of the flange 4. The flange 4 and the sleeve 6 are integrally formed and can be directly cast or machined. The flange 4 is fitted onto the outside of the additional insulation layer 3 through the sleeve 6. The sleeve 6 is connected to the additional insulation layer 3 through the adhesive. The additional insulation layer 3 is mainly used to connect with the flange 4 to seal the gap between the flange 4 and the superconducting cable 1. The sealing insulation layer covers the sleeve 6 and the additional insulation layer 3, and the sealing insulation layer is connected to the main insulation layer 2 to better fix the flange 4 and the additional insulation layer 3, and to better seal the gap between the flange 4 and the superconducting cable 1.
[0036] The adhesive used here is a low-temperature adhesive, which is made by mixing epoxy resin and a curing agent. The mass ratio of epoxy resin to curing agent is 4:1 to achieve the bonding effect.
[0037] The main insulation layer 2 includes, from the inside out, a first pre-impregnated tape half-overlap layer, a pre-impregnated tape and polyimide composite tape half-overlap layer, a second pre-impregnated tape half-overlap layer, a conductive felt layer, and a third pre-impregnated tape half-overlap layer. A wrapping tape is provided between the first pre-impregnated tape half-overlap layer and the pre-impregnated tape and polyimide composite tape half-overlap layer.
[0038] The accompanying tape is woven from fiberglass ribbon and stainless steel strip to provide conductivity. It is positioned between the first pre-impregnated tape half-overlap layer, the pre-impregnated tape, and the polyimide composite tape half-overlap layer of the main insulation layer 2. The pre-impregnated tape and the polyimide composite tape half-overlap layer are clamped together with the first pre-impregnated tape half-overlap layer to form a passage in the main insulation layer 2, connecting to the high-voltage lines of other high-voltage equipment and providing a basis for high-voltage current testing. In this embodiment, the accompanying tape is woven from fiberglass ribbon and stainless steel strip. The width of the accompanying tape is 14 mm to 16 mm, and the thickness of the non-steel strip is 0.17 mm to 0.23 mm. The stainless steel strip is made of grade 316 stainless steel, with a width of 2.7 mm to 2.9 mm and a thickness of 0.04 mm to 0.06 mm.
[0039] The first, second, and third prepreg tape half-overlap layers are formed by wrapping prepreg tape in a half-overlap manner. The prepreg tape is epoxy resin impregnated fiberglass ribbon. In this embodiment, the thickness of the prepreg tape is 0.25 mm and the width is 25 mm. However, different widths and thicknesses of the prepreg tape can be selected according to actual needs.
[0040] The wrapping pattern of a half-fold wrap is as follows: Figure 2 , Figure 3 As shown, a layer of wrapping material with a semi-overlapping wrapping is formed by wrapping a long wrapping tape. Initially, the wrapping tape K wraps around the object J once to form a wrapping loop K1, as shown. Figure 2 As shown; refer to Figure 2 and Figure 3 Then, starting from the midpoint H1 of the beginning of the wrapping loop K1, the tape K wraps around the object J once to form a wrapping loop K2. The wrapping loop K2 can then cover half of the outer surface of the wrapping loop K1. (Refer to...) Figure 3 and Figure 4Next, starting from the midpoint H2 of the beginning of the wrapping loop K2, the wrapping tape K wraps around the object J once to form the wrapping loop K3. In this way, the wrapping tape K can wrap along the length of the object J to form a layer of half-overlapping tape. If the wrapping tape is a prepreg tape, then after the wrapping tape K is completed, a layer of prepreg tape half-overlapping tape is obtained.
[0041] The prepreg tapes in the first, second, and third prepreg tape half-overlap layers are all wrapped in the aforementioned half-overlap form. The first prepreg tape half-overlap layer has 1 to 2 layers, the second prepreg tape half-overlap layer has 1 to 2 layers, and the third prepreg tape half-overlap layer has 2 to 3 layers. The number of prepreg tape half-overlap layers in the first, second, and third prepreg tape half-overlap layers can be adjusted according to actual needs. In this embodiment, the first prepreg tape half-overlap layer has 1 layer, the second prepreg tape half-overlap layer has 1 layer, and the third prepreg tape half-overlap layer has 2 layers.
[0042] The prepreg tape and polyimide composite tape half-overlay has 6 to 9 layers of prepreg tape and polyimide composite tape half-overlay. The number of layers of prepreg tape and polyimide composite tape half-overlay can be adjusted according to actual needs. In this embodiment, the prepreg tape and polyimide composite tape half-overlay has 7 layers of prepreg tape and polyimide composite tape half-overlay. The prepreg tape and polyimide composite tape is a composite tape composed of prepreg tape and polyimide film tape. The width of the polyimide film tape is 21 mm and the thickness is 0.05 mm. The shape of the polyimide film tape X and the prepreg tape Y after being combined is as follows. Figure 5 As shown, the polyimide film tape is arranged parallel to the prepreg tape, with the polyimide film tape located at the geometric center of the prepreg tape. The two side edges of the polyimide film tape are equidistant from the two side edges of the prepreg tape. The polyimide film tape is fixed on the prepreg tape. The wrapping form of the prepreg tape and polyimide composite tape in a half-overlap is the same as that of the prepreg tape in a half-overlap. By using the prepreg tape and polyimide composite tape as wrapping tapes for half-overlap, a prepreg tape and polyimide composite tape half-overlap can be obtained.
[0043] Polyimide film has excellent chemical stability, high temperature resistance, toughness, wear resistance, flame retardancy, and electrical insulation. The pre-impregnated tape and polyimide composite tape are half-overlapped to form an insulating layer, which can improve the insulation effect of the main insulation layer 2 to meet the insulation requirements of the superconducting feeder.
[0044] It should be noted that the glass ribbon layer formed by wrapping in a semi-overlapping manner can increase the fluidity of the epoxy resin, which not only makes the outer surface of the main insulation layer 2 smoother, but also allows the epoxy resin to fill the gaps during wrapping, thereby improving the insulation performance.
[0045] The conductive felt layer has 1 to 3 layers of conductive felt, and the number of conductive felt layers can be adjusted according to actual needs. In this embodiment, the conductive felt layer has 2 layers of conductive felt, which are made of silver-plated nylon felt with a thickness of 0.17 mm. The conductive felt is used to connect to the electrode wire, which is the low-voltage end, providing a basis for current testing of the superconducting feeder.
[0046] The reinforced insulation layer 3 has 14 to 16 layers of pre-impregnated tape semi-overlapping wrapped from the inside out. The number of pre-impregnated tape semi-overlapping layers in the reinforced insulation layer 3 can be adjusted according to actual needs. In this embodiment, the reinforced insulation layer 3 has 15 layers of pre-impregnated tape semi-overlapping. The reinforced insulation layer 3 is mainly used to increase the outer diameter of the main insulation layer 2 and is used to connect with the flange 4 to prevent damage to the main insulation layer 2 caused by the flange 4 connection.
[0047] The reinforcing insulation layer 3 forms steps 7 with the main insulation layer 2 at both ends along the length of the superconducting cable 1. The steps 7 formed between the reinforcing insulation layer 3 and the main insulation layer 2 mainly facilitate quick positioning during subsequent flange 4 installation, making flange 4 installation easier. In this embodiment, the length of the reinforcing insulation layer 3 along the length of the superconducting cable 1 is 491 mm, and the height of the steps 7 is 15 mm.
[0048] To better secure the flange 4, the outer surface of the reinforced insulation layer 3 is provided with external threads, and the inner surface of the sleeve 6 is provided with internal threads that mate with the external threads. That is, external threads are machined on the outer side of the reinforced insulation layer 3. During installation, adhesive is applied to both the external and internal threads, making the connection between the sleeve 6 of the flange 4 and the reinforced insulation layer 3 tighter, thus better securing and sealing the gap between the reinforced insulation layer 3 and the flange 4.
[0049] To better seal the gap between flange 4 and the reinforcing insulation layer 3, the sealing insulation layer is an impregnated glass fiber wrapping layer. This layer consists of glass fiber impregnated with low-temperature adhesive covering the sleeve 6 and the reinforcing insulation layer 3. Before wrapping the glass fiber, the glass fiber impregnated with low-temperature adhesive can be used to fill the ends or grooves where the flange 4 fits against the reinforcing insulation layer 3 to reduce gaps. Then, the glass fiber is wrapped around the surface of the reinforcing insulation layer 3 and the surface of the sleeve 6 of the flange 4, extending to the surface of the main insulation layer 2, so that the sealing insulation layer completely covers the reinforcing insulation layer 3, better securing the flange 4. In this embodiment, the distance between the outer surface of the sealing insulation layer and the outer surface of the reinforcing insulation layer 3 is at least 8 mm to ensure insulation performance. The glass fiber is a glass fiber yarn with good mechanical and insulation properties.
[0050] The superconducting feeder sealing flange structure obtained in this embodiment is tightly installed with the flange 4 through the additional insulation layer 3, and the contact surface between the sealing additional insulation layer 3 and the flange 4 is covered by a sealing insulation layer made of glass fiber, making the flange 4 more reliable in sealing. The superconducting feeder sealing flange structure of this embodiment operates in a low-temperature environment and is suitable for the insulation treatment of radial flange structures in cryogenic feeder channels (CFT). It has a simple structure, is easy to operate, and can ensure the insulation strength and the sealing performance of the radial flange. After the insulation treatment of the CFT components of the fusion reactor superconducting feeder and the radial flange insulation treatment are completed, it has good application value in the field of radial flange sealing insulation treatment.
[0051] This embodiment also provides a method for insulating a superconducting feeder flange, mainly used in the insulation manufacturing of cryostat-feed-through (CFT) channels in superconducting feeder devices, which includes the following steps:
[0052] a: The superconducting cable 1 is wrapped sequentially with a first pre-impregnated tape half-layer, a pre-impregnated tape and polyimide composite tape half-layer, a second pre-impregnated tape half-layer, a conductive felt layer, and a third pre-impregnated tape half-layer to complete the wrapping of the main insulation layer 2; the first pre-impregnated tape half-layer consists of 1 layer of pre-impregnated tape, the pre-impregnated tape and polyimide composite tape half-layer consists of 7 layers of pre-impregnated tape and polyimide composite tape, the second pre-impregnated tape half-layer consists of 1 layer of pre-impregnated tape, the conductive felt layer has 2 layers of conductive felt, and the third pre-impregnated tape half-layer consists of 2 layers of pre-impregnated tape. The wrapping pattern of the half-layers is as follows: Figure 2 , Figure 3As shown, the wrapping form of the semi-overlapping is the same as that of the semi-overlapping of the superconducting feeder sealing flange 4 structure described above; and, when the first prepreg tape semi-overlapping layer is wrapped around the superconducting cable 1, a wrapping tape is wrapped around the outside of the first prepreg tape semi-overlapping layer, and then the wrapping tape and the first prepreg tape semi-overlapping layer are wrapped with the prepreg tape and polyimide composite tape semi-overlapping layer.
[0053] b: 14 to 16 layers of pre-impregnated tape are wrapped around the surface of the main insulation layer 2 in a semi-overlapping manner, forming a step 7 at the tail end, thus forming an additional insulation layer 3 on the surface of the main insulation layer 2; then, the additional insulation layer 3 and the main insulation layer 2 are heated and cured; the step 7 formed between the additional insulation layer 3 and the main insulation layer 2 mainly facilitates quick positioning during subsequent flange 4 installation, making flange 4 installation convenient. In this embodiment, the length of the additional insulation layer 3 along the length direction of the superconducting cable 1 is 491 mm, and the height of the step 7 is 15 mm.
[0054] c: Grind the outer surface of the reinforcing insulation layer 3 until the outer diameter of the reinforcing insulation layer 3 is 63 to 66 mm; then machine the external thread on the outer surface of the reinforcing insulation layer 3 and clean the surface dust; specifically, in this embodiment, by grinding the outer surface of the reinforcing insulation layer 3, the outer diameter of the reinforcing insulation layer 3 is made to 65 mm, and a die is used to machine the external surface thread of the reinforcing insulation layer 3 with a size of M65*1; and alcohol and deionized water are used to clean the dust on the outer surface of the reinforcing insulation layer 3.
[0055] d: Machining an internal thread on the sleeve 6 of flange 4 to match the external thread on the outer surface of the reinforcing layer 3, and cleaning the surface dust; specifically, machining an internal thread on the inner side of the sleeve 6 of flange 4 with a size of M65*1, cleaning the surface dust of the internal thread, and also using alcohol and deionized water to clean the dust on the outer surface of flange 4.
[0056] e: Apply low-temperature adhesive to the internal thread of flange 4 and the external thread of the outer surface of the reinforcing insulation layer 3, and then fit flange 4 onto the external thread of the outer surface of the reinforcing insulation layer 3 that has been coated with low-temperature adhesive; this completes the installation of flange 4. After the installation of flange 4 is completed, glass fiber thread impregnated with low-temperature adhesive can be used to fill the end of sleeve 6 of flange 4 and the groove of flange 4 to reduce gaps.
[0057] f: The glass fiber impregnated with low-temperature adhesive is wrapped around the outer surface of the reinforcing insulation layer 3 and the outer surface of the sleeve 6 of the flange 4, and extended to the outer surface of the main insulation layer 2 to form a sealed insulation layer.
[0058] g: The sealing insulation layer is heated and cured to complete the insulation treatment of the superconducting feeder flange 4.
[0059] The heating and curing process for the sealing insulation layer is as follows: A non-porous isolation membrane is wrapped around the sealing insulation layer, and both ends are sealed. Then, a breathable felt is wrapped around the surface of the non-porous isolation membrane, followed by a vacuum bag film wrapped around the breathable felt and sealed with a sealing strip. The inside of the vacuum bag film is connected to a vacuum gauge and an air extraction system via a hose. The air extraction system then evacuates the space inside the non-porous isolation membrane to below 500 Pa. Next, an insulating felt is wrapped around the surface of the vacuum bag film, followed by aluminum foil. Finally, a heating tape is wrapped around the aluminum foil. The heating tape is then activated, raising the temperature at 0.5 degrees Celsius per minute to 60 degrees Celsius and maintaining this temperature between 60 and 65 degrees Celsius for 6 hours. The temperature is then raised to 80 degrees Celsius and maintained between 80 and 85 degrees Celsius for 3 hours, followed by natural cooling to complete the curing process. The final flange 4 sealing structure is tested using a helium mass spectrometer to check the sealing performance of flange 4 and the sealing insulation. A leakage rate better than 10⁻⁹ Pa*m³ / s is considered a good seal.
[0060] It should be noted that, in this embodiment, the wrapping tape is woven from fiberglass ribbon and stainless steel tape, with a width of 14 mm to 16 mm and a thickness of 0.17 mm to 0.23 mm in the non-steel sections; the stainless steel tape is made of grade 316 stainless steel, with a width of 2.7 mm to 2.9 mm and a thickness of 0.04 mm to 0.06 mm. The pre-impregnated tape is epoxy resin-impregnated fiberglass ribbon, with a thickness of 0.25 mm and a width of 25 mm. The pre-impregnated tape and polyimide composite tape is a composite tape composed of pre-impregnated tape and polyimide film tape, with a width of 21 mm and a thickness of 0.05 mm; the polyimide film tape is arranged parallel to the pre-impregnated tape, and the polyimide film tape is located at the geometric center of the pre-impregnated tape, with the two side edges of the polyimide film tape equidistant from the two side edges of the pre-impregnated tape. A polyimide film tape is fixed onto a prepreg tape. The wrapping pattern of the prepreg tape and polyimide composite tape in a semi-overlapping manner is the same as that of the prepreg tape in a semi-overlapping manner. By using the prepreg tape and polyimide composite tape as wrapping tapes for semi-overlapping, a semi-overlapping of prepreg tape and polyimide composite tape can be obtained. The low-temperature adhesive is an adhesive made by uniformly mixing epoxy resin and curing agent in a mass ratio of 4:1.
[0061] In summary, the superconducting feeder sealing flange structure obtained in this embodiment is tightly installed with the flange 4 through the additional insulation layer 3, and the sealing insulation layer made of glass fiber wraps the contact surface between the sealing insulation layer 3 and the flange 4, making the flange 4 more reliable in sealing. The superconducting feeder sealing flange structure of this embodiment operates in a low-temperature environment and is suitable for the insulation treatment of radial flange structures in cryogenic feeder channels (CFT). It has a simple structure, is easy to operate, and can ensure the insulation strength and the sealing performance of the radial flange. After the insulation treatment of the CFT components of the fusion reactor superconducting feeder and the radial flange insulation treatment are completed, it has good application value in the field of radial flange sealing insulation treatment.
[0062] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make several improvements and substitutions without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.
Claims
1. A sealing flange structure for a superconducting feeder, characterized in that, include: Superconducting cable, main insulation layer, additional winding insulation layer, flange, adhesive, sealing insulation layer; The main insulation layer is wrapped around the outside of the superconducting cable, and the additional insulation layer is wrapped around the outside of the main insulation layer; a sleeve is provided on the inner side of the flange, and the flange is sleeved on the outside of the additional insulation layer through the sleeve, and the sleeve is connected to the additional insulation layer through the adhesive; the sealing insulation layer covers the sleeve and the additional insulation layer, and the sealing insulation layer is connected to the main insulation layer.
2. The superconducting feeder sealing flange structure according to claim 1, characterized in that, The main insulation layer includes, from the inside out, a first pre-impregnated tape half-overlay layer, a pre-impregnated tape and polyimide composite tape half-overlay layer, a second pre-impregnated tape half-overlay layer, a conductive felt layer, and a third pre-impregnated tape half-overlay layer, wherein a wrapping tape is provided between the first pre-impregnated tape half-overlay layer and the pre-impregnated tape and polyimide composite tape half-overlay layer.
3. The superconducting feeder sealing flange structure according to claim 2, characterized in that, The first prepreg tape half-overlay layer has 1 to 2 layers of prepreg tape half-overlay, the prepreg tape and polyimide composite tape half-overlay layer has 6 to 9 layers of prepreg tape and polyimide composite tape half-overlay, the second prepreg tape half-overlay layer has 1 to 2 layers of prepreg tape half-overlay, the conductive felt layer has 1 to 3 layers of conductive felt, and the third prepreg tape half-overlay layer has 2 to 3 layers of prepreg tape half-overlay.
4. The superconducting feeder sealing flange structure according to claim 1, characterized in that, The reinforced insulation layer has 14 to 16 layers of pre-impregnated tape semi-overlapping wrapped from the inside out.
5. The superconducting feeder sealing flange structure according to claim 4, characterized in that, The additional insulation layer forms steps with the main insulation layer at both ends along the length of the superconducting cable.
6. The superconducting feeder sealing flange structure according to claim 1, characterized in that, The outer surface of the reinforcing insulation layer is provided with an external thread, and the inner surface of the sleeve is provided with an internal thread that mates with the external thread.
7. The superconducting feeder sealing flange structure according to claim 1, characterized in that, The sealing insulation layer is an impregnated glass fiber wrapping layer, which is formed by wrapping the sleeve and the additional insulation layer with glass fiber impregnated with low-temperature adhesive.
8. A method for insulating a superconducting feeder flange, characterized in that, Includes the following steps: a: The superconducting cable is wrapped sequentially with a first pre-impregnated tape half-layer, a pre-impregnated tape and polyimide composite tape half-layer, a second pre-impregnated tape half-layer, a conductive felt layer, and a third pre-impregnated tape half-layer to complete the wrapping of the main insulation layer; wherein, when the first pre-impregnated tape half-layer is wrapped around the superconducting cable, a wrapping tape is wrapped around the outside of the first pre-impregnated tape half-layer, and then the wrapping tape and the first pre-impregnated tape half-layer are wrapped with a pre-impregnated tape and polyimide composite tape half-layer; b: 14 to 16 layers of pre-impregnated tape are wrapped around the surface of the main insulation layer in a semi-overlapping manner, thus forming an additional winding insulation layer on the surface of the main insulation layer; then the additional winding insulation layer and the main insulation layer are heated and cured. c: Grind the outer surface of the reinforcing insulation layer until the outer diameter of the reinforcing insulation layer is 63 to 66 mm; then machine the external threads on the outer surface of the reinforcing insulation layer and clean the surface dust. d: Machining the flange sleeve to match the internal thread of the external thread on the outer surface of the insulation layer, and cleaning the surface dust; e: Apply low-temperature adhesive to the internal threads of the flange and the external threads of the outer surface of the reinforcing insulation layer, and then fit the flange onto the external threads of the outer surface of the reinforcing insulation layer that has been coated with low-temperature adhesive; f: The glass fiber impregnated with low-temperature adhesive is wrapped around the outer surface of the reinforcing insulation layer and the outer surface of the flange sleeve, and extended to the outer surface of the main insulation layer to form a sealed insulation layer; g: The sealing insulation layer is heated and cured to complete the insulation treatment of the superconducting feeder flange.
9. The method for insulating a superconducting feeder flange according to claim 8, characterized in that, In step a, the first prepreg tape half-overlay layer is a 1-layer prepreg tape half-overlay, the prepreg tape and polyimide composite tape half-overlay layer is a 7-layer prepreg tape and polyimide composite tape half-overlay, the second prepreg tape half-overlay layer is a 1-layer prepreg tape half-overlay, the conductive felt layer has 2 layers of conductive felt, and the third prepreg tape half-overlay layer is a 2-layer prepreg tape half-overlay.
10. The method for insulating a superconducting feeder flange according to claim 8, characterized in that, The low-temperature adhesive is an adhesive made by mixing epoxy resin and curing agent in a mass ratio of 4:1.