A processing method for the helium holes of a superconducting magnet of a CICC conductor

Abstract

The present application relates to the technical field of coil production for electromagnetic devices and discloses a method for machining a superconducting magnet helium hole for a CICC conductor. The machining method comprises the following steps: Step 1: Positioning the superconducting magnet helium hole on the CICC conductor; Step 2: Mounting the CICC conductor on a punching device; Step 3: After adjusting the rotation speed of a first milling cutter to a preset constant value, controlling the feed of the first milling cutter to mill and form a first milling hole; Step 4: Replacing the first milling cutter in the punching device with a second milling cutter, adjusting the pitch angle of the second milling cutter relative to the first milling hole, and controlling the feed of the second milling cutter to form a second milling hole, wherein visible cracks appear on the wall surface of the second metal cladding at the second milling hole; Step 5: Manually removing the remaining portion of the second metal cladding and the first metal cladding to form a superconducting magnet helium hole that sequentially penetrates the second metal cladding and the first metal cladding. This reduces the risk of damage to the cable body.

Description

Technical Field

[0001] The present application relates to the technical field of coil production for electromagnetic devices, and in particular to a method for processing helium holes in superconducting magnets of CICC conductors. Background Art

[0002] Coils are a crucial component of magnetic confinement fusion devices. Large superconducting coils are typically formed by winding superconducting materials. CICC conductors are a commonly used type of superconducting coil conductor. CICC conductors are multi-stage cables, made by twisting multiple strands of stranded cables together, then wrapping them with a thin stainless steel sheath for protection, and then inserting them into a stainless steel tube and extruding them into shape.

[0003] Currently, when CICC conductors are used in magnetic confinement nuclear fusion devices, it is necessary to process a hole structure connecting the helium tube on the CICC conductor and perform welding processing on the helium tube at the CICC conductor to serve as a channel for liquid helium inside the coil formed by connecting the CICC conductor.

[0004] The hole structure requires high machining precision to avoid damage to the cable body in the CICC conductor. In related technologies, the hole structure is typically manually machined by an operator, requiring extensive operator experience and requiring high concentration, resulting in a heavy workload. Summary of the Invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a method for machining helium holes in a superconducting magnet of a CICC conductor, so as to reduce the risk of damage to the cable body during the machining process.

[0006] According to an embodiment of the present application, a method for processing a superconducting magnet helium hole of a CICC conductor includes a cable body and a first metal coating layer and a second metal coating layer sequentially covering the cable body. The processing method includes the following steps: Step 1: Marking a line on the CICC conductor to locate the position of the superconducting magnet helium hole; Step 2: Installing and cooperating the CICC conductor with a punching device, so that the punching device clamps and fixes the helium hole region transition section conductor in the CICC conductor, and aligning a first milling cutter on the punching device with a starting point for punching the superconducting magnet helium hole; Step 3: After adjusting the rotation speed of the first milling cutter to a preset constant value, controlling the rotation speed of the first milling cutter to reach a predetermined constant value, The first milling cutter is controlled to advance to mill the second metal cladding to form a first milling hole, and visible cracks appear on the wall surface of the second metal cladding at the first milling hole; Step 4, the first milling cutter in the punching device is replaced with a second milling cutter, and the pitch angle of the second milling cutter relative to the first milling hole is adjusted, and the second milling cutter is controlled to advance to mill the second metal cladding to form a second milling hole; Step 5, the punching device is lifted out, and the remaining part of the second metal cladding and the first metal cladding are removed by manual root cleaning to form the superconducting magnet helium hole that sequentially penetrates the second metal cladding and the first metal cladding.

[0007] According to some embodiments of the present application, step 1 further includes: using an infrared level to accurately transfer the position of the superconducting magnet helium hole to the helium hole region transition section conductor, and marking the size of the superconducting magnet helium hole on the helium hole region transition section conductor.

[0008] According to some embodiments of the present application, the punching device comprises a base, a conductor clamp, and a milling device. The conductor clamp is disposed on the base and is used to clamp and fix the conductor of the helium hole region transition section in step 2. The milling device is adjustable on the base. Step 2 further comprises: adjusting the milling device to be parallel to the conductor of the helium hole region transition section, and then clamping and fixing the conductor of the helium hole region transition section by the conductor clamp.

[0009] According to some embodiments of the present application, the milling device has a universal side milling head, which is used to install the first milling cutter or the second milling cutter. Step four also includes: adjusting the universal side milling head to adjust the pitch angle of the second milling cutter relative to the first milling hole.

[0010] According to some embodiments of the present application, in step three, controlling the first milling cutter to feed to mill the second metal cladding layer to form a first milling hole includes: controlling the punching device to feed the first milling cutter located at the starting point to reach a first feed depth value, and then controlling the first milling cutter to mill horizontally to a first position; after the first milling cutter is milled horizontally to the first position, controlling the punching device to feed the first milling cutter to reach a second feed depth value, and then controlling the first milling cutter to mill horizontally to a second position; wherein, the second position and the starting point coincide in the feed direction of the first milling cutter, and the first milling cutter can be controlled to feed reciprocatingly between the first position and the second position.

[0011] According to some embodiments of the present application, the helium hole of the superconducting magnet is an oblong hole, and the first position and the second position are edge positions on both sides of the oblong hole in the length direction, respectively.

[0012] According to some embodiments of the present application, in step three, after the cumulative feed amount of the first milling cutter during the reciprocating milling process between the first position and the second position reaches a preset value, the first milling cutter is controlled to the first position, and after feeding at a third feed depth value, the first milling cutter is controlled to mill horizontally to the second position; after the first milling cutter mills horizontally to the second position, the punching device is controlled to feed the first milling cutter to reach a fourth feed depth value, and then the first milling cutter is controlled to mill horizontally to the first position; wherein, the fourth feed depth value is not less than the third feed depth value, and the third feed depth value and the fourth feed depth value are both less than the first feed depth value and the second feed depth value.

[0013] According to some embodiments of the present application, the first feed depth value is 0.3 mm, the second feed depth value is 0.3 mm, the third feed depth is 0.1 mm, and the fourth feed depth is 0.2 mm.

[0014] According to some embodiments of the present application, the second milling cutter is a dovetail milling cutter. In step four, adjusting the pitch angle of the second milling cutter relative to the first milling hole includes: adjusting the second milling cutter to a pitch angle with the horizontal plane, and moving the second milling cutter to the root position of the upper part of the first milling hole; adjusting the second milling cutter to an elevation angle with the horizontal plane, and moving the second milling cutter to the root position of the lower part of the first milling hole.

[0015] According to some embodiments of the present application, in step four, controlling the second milling cutter to feed to mill the second metal cladding layer to form a second milling hole includes: controlling the second milling cutter to have a single feed depth of no more than 0.1 mm.

[0016] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 is a flow chart of a method for machining a helium hole in a superconducting magnet of a CICC conductor according to one embodiment of the present application;

[0019] Figure 2 is a cross-sectional schematic diagram of a CICC conductor according to one embodiment of the present application;

[0020] Figure 3 This is a schematic diagram of the cooperation between the CICC conductor and the second milling cutter according to an embodiment of the present application. Figure 1 ;

[0021] Figure 4 This is a schematic diagram of the cooperation between the CICC conductor and the second milling cutter according to an embodiment of the present application. Figure 2 ;

[0022] Figure 5 is a schematic diagram of a helium hole region transition section conductor according to one embodiment of the present application;

[0023] Figure 6 is a schematic diagram of a multi-segment helium hole region transition section conductor according to one embodiment of the present application;

[0024] Figure 7 This is a schematic diagram of the structure of a punching device according to an embodiment of the present application. Figure 1 ;

[0025] Figure 8 This is a schematic diagram of the structure of a punching device according to an embodiment of the present application. Figure 2 ;

[0026] Figure 9 Schematic diagram of the cooperation between the punching device and the CICC conductor according to one embodiment of the present application;

[0027] Figure 10 1 is a schematic diagram of partial coordination between a punching device and a CICC conductor according to one embodiment of the present application;

[0028] Figure 11 It is a schematic top view of a coil winding production line according to one embodiment of the present application.

[0029] Reference numerals:

[0030] Coil winding production line 1000;

[0031] Rotating platform and mold 210; automatic control console 300; bending and forming device 400; conductor support device 500; sandblasting cleaning device 600; ultrasonic cleaning device 700; conductor straightening device 800; conductor feeding device 900;

[0032] CICC conductor 100;

[0033] Cable body 1; first metal cladding layer 2; second metal cladding layer 3; first milling hole 31; second milling hole 32; superconducting magnet helium hole 10; helium hole region transition section conductor 20;

[0034] Punching device 200;

[0035] Base body 4; conductor clamp 5; pre-tightening bolt 51; milling device 6; bracket 61; power motor 62; universal side milling head 63; second milling cutter 7; transverse adjustment device 81; longitudinal adjustment device 82; swing adjustment device 83. DETAILED DESCRIPTION

[0036] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0037] Reference below Figures 1-11 A method for fabricating a superconducting magnet helium hole 10 of a CICC (Cable-in-Conduit Conductor) conductor 100 (superconducting cable conductor) according to an embodiment of the present application is described. The method is used to form a superconducting magnet helium hole 10 on a CICC conductor 100. The CICC conductor 100 includes a cable body 1 and a first metal cladding layer 2 and a second metal cladding layer 3 that sequentially cover the cable body 1.

[0038] Coils are a crucial component of magnetic confinement fusion devices. Large superconducting coils are typically formed by winding superconducting materials. CICC conductor 100 is a commonly used superconducting coil conductor and a multi-stage cable. Multiple strands are twisted together to form the cable body 1 described above. This cable body 1 is then protected by a thin stainless steel sheath (the first metal cladding layer 2) and then inserted into a stainless steel tube (the second metal cladding layer 3, such as 316LN stainless steel) for extrusion.

[0039] Currently, when a CICC conductor 100 is used in a magnetic confinement nuclear fusion device, a hole structure connecting to a helium tube must be machined on the CICC conductor 100, and the helium tube must be welded to the CICC conductor 100 to serve as a channel for liquid helium inside the coil formed by the CICC conductor 100. The hole structure requires high machining precision to avoid damage to the cable body 1 in the CICC conductor 100. In related art, the hole structure is typically machined manually by an operator, requiring extensive operator experience and high workload, requiring them to maintain high concentration.

[0040] The processing method according to the embodiment of the present application includes the following steps: Step 1: Marking the position of the superconducting magnet helium hole 10 on the CICC conductor 100; Step 2: Installing and cooperating the CICC conductor 100 with the punching device 200, so that the helium hole region transition section conductor 20 in the CICC conductor 100 is clamped and fixed by the punching device 200, and the first milling cutter on the punching device 200 is aligned with the punching starting point of the superconducting magnet helium hole 10; Step 3: After adjusting the rotation speed of the first milling cutter to a preset constant value, controlling the first milling cutter to feed to mill the second metal cladding layer 3 to form the first milling cutter. A hole 31 is cut, and visible cracks appear on the wall of the second metal cladding layer 3 at the first milling hole 31; step 4, replacing the first milling cutter in the punching device 200 with the second milling cutter 7, and adjusting the pitch angle of the second milling cutter 7 relative to the first milling hole 31, controlling the feed of the second milling cutter 7 to mill the second metal cladding layer 3 to form a second milling hole 32; step 5, lifting the punching device 200, and manually removing the remaining part of the second metal cladding layer 3 and the first metal cladding layer 2 by root cleaning, to form a superconducting magnet helium hole 10 that sequentially penetrates the second metal cladding layer 3 and the first metal cladding layer 2.

[0041] It should be noted that when the CICC conductor 100 is being processed into the superconducting magnet helium hole 10, it is located on the coil winding production line. When the punching device 200 is used to punch holes in the CICC conductor 100, the punching device 200 can be hoisted and positioned at the helium hole region transition section conductor 20 in the CICC conductor 100 where the superconducting magnet helium hole 10 is to be formed. The punching device 200 cooperates with the helium hole region transition section conductor 20 to perform the hole processing operation. The "helium hole region transition section conductor 20" referred to above refers to the portion of the CICC conductor 100 where the helium hole 10 is to be formed.

[0042] In the processing method of the present application, the processing position where the superconducting magnet helium hole 10 needs to be opened in the CICC conductor 100 can be determined based on the layout requirements of the helium tube, and the processing position of the superconducting magnet helium hole 10 can be marked and positioned on the CICC conductor 100 to facilitate the subsequent alignment of the drilling device 200 with the processing position of the superconducting magnet helium hole 10.

[0043] Furthermore, the CICC conductor 100 is mounted and matched with the installation equipment. The punching equipment 200 clamps and secures the helium hole region transition section conductor 20, which requires drilling. This prevents the helium hole region transition section conductor 20 from shaking during the drilling process, thereby improving the machining accuracy of the superconducting magnet helium hole 10. Simultaneously, the first milling cutter provided on the punching equipment 200 can be aligned with the drilling location of the superconducting magnet helium hole 10, facilitating subsequent milling of the second metal cladding layer 3 on the CICC conductor 100 by the punching equipment 200.

[0044] The punching device 200 may be equipped with a variety of cutting tools, such as the first milling cutter and the second milling cutter 7 mentioned above, so as to perform hole processing on the CICC conductor 100 using the first milling cutter and the second milling cutter 7 respectively.

[0045] During the processing of the second metal cladding layer 3 by the punching device 200, the rotation speed of the first milling cutter is first adjusted to a preset constant value (e.g., 2000 rpm, 3000 rpm, etc., Revolutions Per Minute), and the feed of the first milling cutter is controlled to mill the second metal cladding layer 3 to form a first milling hole 31, so that visible cracks can appear on the wall surface of the second metal cladding layer 3 at the first milling hole 31.

[0046] After forming the first milling hole 31, the second milling cutter 7 is mounted on the punching device 200 and adjusted into the first milling hole 31. The second milling cutter 7 is then used to further mill the second metal cladding layer 3, thereby further increasing the root depth of the hole structure formed in the second metal cladding layer 3. The second milling cutter 7 also needs to adjust its rotational speed to a preset constant value before milling. The milling speed of the second milling cutter 7 can be the same as that of the first milling cutter.

[0047] It is understood that the pitch angle of the second milling cutter 7 during milling of the first milling hole 31 causes the second milling hole 32 to expand gradually from the milling portion of the second milling cutter 7 toward the inner side of the CICC conductor 100 (i.e., the side of the first metal cladding 2 opposite the second metal cladding 3). This increases the operating space for subsequent manual root cleaning by the operator and reduces the difficulty of manual root cleaning. Furthermore, the drilling device 200 is stopped after the first milling cutter has machined the hole in the second metal cladding 3 to avoid cracks. This prevents the first milling cutter from directly penetrating the second metal cladding 3 and, therefore, from direct contact with the first metal cladding 2, potentially penetrating the first metal cladding 2 and damaging the cable body 1. Among them, the first metal cladding layer 2 is wrapped on the cable body 1 to fit tightly with the cable body 1, and the thickness of the first metal cladding layer 2 is relatively thin. If the first milling cutter contacts the first metal cladding layer 2, there is a risk of damaging the cable body 1. Therefore, in the processing method of the present application, the punching device 200 is stopped after visible cracks appear on the wall of the second metal cladding layer 3 to avoid damage to the cable body 1 by the first milling cutter.

[0048] After the second milling hole 32 is formed in the CICC conductor 100, the punching device 200 can be separated from the CICC conductor 100 to reserve sufficient operating space on the side of the CICC conductor 100 where the second milling hole 32 is formed. The operator can manually clean the second milling hole 32 using a dedicated tool to remove the remaining second metal cladding layer 3 of the CICC conductor 100 at the second milling hole 32 and the first metal cladding layer 2 corresponding to the second milling hole 32, thereby forming a superconducting magnet helium hole 10 that penetrates the second metal cladding layer 3 and the first metal cladding layer 2 from the outside to the inside, thereby completing the processing of the superconducting magnet helium hole 10.

[0049] It should be noted that the special tools used by operators include but are not limited to electric grinders (such as handheld oil-free electric grinders), needle-nose pliers, tungsten steel scribers, etc.

[0050] In the method for processing the superconducting magnet helium hole 10 of the CICC conductor 100 of the embodiment of the present application, the punching device 200 is used in conjunction with manual operation to first mill the CICC conductor 100 to sufficiently reduce the thickness of the second metal cladding layer 3 until the second metal cladding layer 3 is cracked, and then the operator manually performs root cleaning to form the superconducting magnet helium hole 10, thereby reducing the risk of damage to the cable body 1 while reducing the operator's operating difficulty and workload. In addition, the second milling cutter 7 is used for pitch and elevation milling operations to locally remove material from the difficult-to-clean location at the root of the first milling hole 31, significantly reducing the difficulty of subsequent manual root cleaning and improving the operator's root cleaning efficiency.

[0051] At the same time, during the processing of the superconducting magnet helium hole 10, the processing position of the superconducting magnet helium hole 10 is marked and positioned, and the punching device 200 is clamped and cooperated with the helium hole region transition section conductor 20, thereby improving the punching accuracy of the CICC conductor 100 by the punching device 200.

[0052] In some embodiments of the present application, step 1 further includes: using an infrared level to accurately transfer the position of the superconducting magnet helium hole 10 to the helium hole region transition section conductor 20, and marking the dimensions of the superconducting magnet helium hole 10 on the helium hole region transition section conductor 20. The marking method may be line marking.

[0053] During the marking process, the surface of the conductor 20 in the transition section of the helium hole area can be marked first with an infrared level, and the error can be controlled within a range of 1 mm. A drawing stylus and a positioning tool are used to mark the length and width dimensions of the superconducting magnet helium hole 10 to ensure the accuracy of the subsequent hole processing by the punching device 200.

[0054] Combine Figure 7 and Figure 8 As shown, in some embodiments of the present application, the punching device 200 has a base body 4, a conductor clamp 5 and a milling device 6. The conductor clamp 5 is arranged on the base body 4. The conductor clamp 5 is used to clamp and fix the helium hole area transition section conductor 20 in step 2. The milling device 6 is adjustable on the base body 4.

[0055] The conductor clamp 5 can be fixedly matched with the base body 4 so that after the helium hole region transition section conductor 20 is clamped by the conductor clamp 5, the position of the helium hole region transition section conductor 20 relative to the base body 4 is kept fixed, and the position of the milling device 6 on the base body 4 can be further adjusted so that the tool installed on the milling device 6 corresponds to the hole processing position in the helium hole region transition section conductor 20.

[0056] In the punching device, a transverse adjustment device 81, a longitudinal adjustment device 82 and a swing adjustment device 83 are arranged between the base body 4 and the milling device 6. The transverse adjustment device 81 can adjust the relative position between the milling device 6 and the base body 4 along the transverse direction, the longitudinal adjustment device 82 can adjust the relative position between the milling device 6 and the base body 4 along the longitudinal direction, and the swing adjustment device 83 can adjust the horizontal position of the milling device 6 relative to the base body 4, so as to facilitate the arrangement of the milling device 6 corresponding to the hole processing position.

[0057] It should be noted that both the lateral and longitudinal adjustment directions are directional adjustments located in the same horizontal plane, and the lateral adjustment direction is perpendicular to the longitudinal adjustment direction. The longitudinal adjustment direction also corresponds to the inward-outward direction of the CICC conductor 100. Longitudinally adjusting the milling device 6 moves the milling device 6 toward or away from the CICC conductor 100. The swing adjustment device 83 can drive the milling device 6 to swing about the first axis relative to the base 4, thereby adjusting the inclination angle of the milling device 6 relative to the horizontal plane. Furthermore, the aforementioned adjustment devices (e.g., the lateral adjustment device 81, the longitudinal adjustment device 82, and the swing adjustment device 83) can be composed of worm gears, gear structures, etc., and the specific structure of the adjustment devices is not limited herein.

[0058] Reference Figure 7 As shown, the milling device 6 includes a bracket 61 and a power motor 62. The bracket 61 is a mounting carrier for the power motor 62. The power motor 62 is used to drive the tool to rotate to achieve the milling function of the milling device 6. The bracket 61 is connected to the base 4 via the aforementioned adjustment device. The position of the power motor 62 and the tool arranged on the power motor 62 can be adjusted by adjusting the position of the bracket 61 relative to the base 4. The conductor clamp 5 is arranged on the side of the power motor 62 for mounting the tool.

[0059] Furthermore, step 2 further includes: adjusting the milling device 6 to be parallel to the helium hole region transition section conductor 20, and then clamping and fixing the helium hole region transition section conductor 20 with the conductor clamp 5. Thus, the helium hole region transition section conductor 20 is fixed by the conductor clamp 5.

[0060] Reference Figure 7 As shown, the conductor fixture 5 is formed with a mounting groove for accommodating the above-mentioned helium hole region transition section conductor 20. A pre-tightening bolt 51 is provided in the conductor fixture 5. The pre-tightening bolt 51 passes through the wall of the mounting groove and is used to clamp and fix the helium hole region transition section conductor 20, thereby improving the reliability of the conductor fixture 5 in clamping and fixing the helium hole region transition section conductor 20.

[0061] When the helium hole region transition section conductor 20 extends in an arc shape, a proper amount of pads may be arranged in the installation groove to fill it, so as to ensure the stability of the conductor clamp 5 in clamping the helium hole region transition section conductor 20 .

[0062] like Figure 7 As shown, in a further embodiment of the present application, the milling device 6 has a universal side milling head 63 , which is used to install the first milling cutter or the second milling cutter 7 .

[0063] It is understandable that the universal side milling head 63 is connected to the output end of the power motor 62 and is used to install the tool. The angle of the tool can be adjusted through the universal side milling head 63 to facilitate adjusting the pitch angle of the second milling cutter 7.

[0064] Furthermore, step four also includes: adjusting the universal side milling head 63 to adjust the pitch angle of the second milling cutter 7 relative to the first milling hole 31, thereby adjusting the second milling cutter 7 to an angle suitable for milling the root of the first milling hole 31, thereby achieving further inwardly expanding milling at the first milling hole 31, increasing the opening range of the hole structure to the inside, and reducing the operating difficulty of the operator.

[0065] In some embodiments of the present application, in step three, controlling the feed of the first milling cutter to mill the second metal cladding layer 3 to form a first milling hole 31 includes: controlling the punching device 200 to feed the first milling cutter located at the starting point to reach a first feed depth value, and then controlling the first milling cutter to mill horizontally to a first position; after the first milling cutter is milled horizontally to the first position, controlling the punching device 200 to feed the first milling cutter to reach a second feed depth value, and then controlling the first milling cutter to mill horizontally to a second position.

[0066] The second position and the starting point coincide with each other in the feeding direction of the first milling cutter, and the first milling cutter can be controlled to reciprocate between the first position and the second position to form a first milling hole 31 in the second metal cladding layer 3 by the first milling cutter.

[0067] Specifically, the first milling cutter begins to feed from the actual point, and after the feed depth of the first milling cutter reaches a first feed depth value, the first milling cutter is moved horizontally to a first position to form a hole structure with an oblong opening by the first milling cutter. After the first milling cutter reaches the first position, the first milling cutter is further controlled to feed, and after the feed depth of the first milling cutter reaches a second feed depth value, the first milling cutter is controlled to mill horizontally to a second position (i.e., a position corresponding to the starting point in the feed direction), thereby deepening the depth of the hole structure. Thus, by cyclically executing the above operations, the feed depth of the first milling cutter can be gradually increased, and the first milling hole 31 can be machined to a preset depth.

[0068] Reference Figure 5 and Figure 10 As shown, in a further embodiment of the present application, the superconducting magnet helium hole 10 is an oblong hole, and the first position and the second position are the edge positions on both sides of the oblong hole in the length direction, respectively, so that the first milling cutter can be reciprocated between the first position and the second position, and the feeding action of the first milling cutter is performed before each translation, such as: controlling the first milling cutter to feed the first preset depth value, and controlling the first milling cutter to feed the second depth value.

[0069] In some embodiments of the present application, in step three, after the cumulative feed amount of the first milling cutter during the reciprocating milling process between the first position and the second position reaches a preset value, the first milling cutter is controlled to the first position, and after feeding at a third feed depth value, the first milling cutter is controlled to mill horizontally to the second position; after the first milling cutter mills horizontally to the second position, the punching device 200 is controlled to feed the first milling cutter to reach a fourth feed depth value, and then the first milling cutter is controlled to mill horizontally to the first position.

[0070] The fourth feed depth value is not less than the third feed depth value, and both the third feed depth value and the fourth feed depth value are less than the first feed depth value and the second feed depth value.

[0071] Therefore, after the cumulative feed amount of the first milling cutter reaches the preset value, the feed amount of each time of the first milling cutter can be adjusted to the third feed depth value and the fourth feed depth value, and the second metal cladding layer 3 can be further milled by the first milling cutter until obvious visible cracks are seen in the second metal cladding layer 3, and the milling action of the first milling cutter is stopped.

[0072] It should be noted that the cumulative feed rate of the first milling cutter needs to be less than the wall thickness of the second metal cladding layer 3 before milling. In other words, the cumulative feed rate of the first milling cutter is L1, and the wall thickness of the second metal cladding layer 3 is L2, where L2>L1. This prevents the second metal cladding layer 3 from being directly penetrated due to excessive single feed rate of the first milling cutter. The difference between L2 and L1 is preferably 0.5 mm, but is not limited to this.

[0073] It can be understood that when the first milling cutter feeds at the first feed depth value or the second feed depth value each time, the feed depth of the first milling cutter is larger, thereby improving the processing efficiency of the first milling hole 31; when the first milling cutter feeds at the third feed depth value or the fourth feed depth value each time, the residual thickness of the wall of the second metal cladding 3 corresponding to the hole structure is smaller, and the direct penetration of the second metal cladding 3 by the first milling cutter can be reduced by reducing the single feed depth of the first milling cutter, so as to facilitate keeping the second metal cladding 3 in a state where obvious visible cracks are formed.

[0074] In a specific embodiment of the present application, the first feed depth value is 0.3 mm, the second feed depth value is 0.3 mm, the third feed depth is 0.1 mm, and the fourth feed depth is 0.2 mm.

[0075] It is understood that if the single feed rate is maintained at the first feed depth value or the second feed depth value when the cumulative feed depth of the first milling cutter reaches the preset value, there will be a risk of direct penetration of the second metal cladding layer 3. In the present application, by adjusting the single feed rate of the first milling cutter, the wall surface can be directly penetrated by the second metal cladding layer 3 due to the excessive single feed rate of the first milling cutter, thereby improving the hole processing reliability of the drilling device 200.

[0076] Combine Figure 3 and Figure 4 As shown, in some embodiments of the present application, the second milling cutter 7 is a dovetail milling cutter. In step four, adjusting the pitch angle of the second milling cutter 7 relative to the first milling hole 31 includes: adjusting the second milling cutter 7 to be at a pitch angle with the horizontal plane, and moving the second milling cutter 7 to the root position of the upper part of the first milling hole 31; adjusting the second milling cutter 7 to be at an elevation angle with the horizontal plane, and moving the second milling cutter 7 to the root position of the lower part of the first milling hole 31.

[0077] Thus, the root of the first milling hole 31 can be further milled by the second milling cutter 7 to form a second milling hole 32. The second milling hole 32 is slightly deeper than the first milling hole 31 at the root of the hole structure, thereby reducing the difficulty of subsequent manual root cleaning by the operator.

[0078] Reference Figure 3 As shown, when the second milling cutter 7 is tilted downward relative to the first milling hole 31, the second milling cutter 7 has a downward depression angle relative to the horizontal direction, so that the root position of the upper part of the first milling hole 31 can be milled; Figure 4 As shown, when the second milling cutter 7 is tilted upward relative to the first milling hole 31, the second milling cutter 7 has an upward elevation angle relative to the horizontal direction, so that the root position of the lower part of the first milling hole 31 can be milled.

[0079] In a further embodiment of the present application, in step four, controlling the feed of the second milling cutter 7 to mill the second metal cladding layer 3 to form a second milling hole 32 includes: controlling the single feed depth of the second milling cutter 7 to be no more than 0.1 mm, which can be 0.05 mm, 0.08 mm, etc.

[0080] It can be understood that after the second metal cladding 3 is milled by the first milling cutter, visible cracks have been formed in the wall area of the second metal cladding 3 corresponding to the first milling hole 31. If the single feed amount of the second milling cutter 7 is too large, the second milling cutter 7 will be at risk of penetrating the second metal cladding 3. The present application controls the single feed depth of the second milling cutter 7 within the range of 0.1 mm, thereby reducing the risk of the second metal cladding 3 being penetrated by the second milling cutter 7 while milling the root of the first milling hole 31, improving the hole processing reliability of the punching equipment 200, and reducing the risk of the cable body 1 being damaged by the tool.

[0081] In some embodiments of the present application, the total feed depth of the second milling hole 32 is less than the wall thickness of the second metal cladding layer 3 , thereby preventing the second tool from penetrating the second metal cladding layer 3 .

[0082] It should be noted that in the CICC conductor 100, after the second metal cladding layer 3 is applied to the cable body 1 coated with the first metal cladding layer 2, the second metal cladding layer 3 needs to be extruded. As a result, the thickness of the second metal cladding layer 3 at different positions will have slight differences. By controlling the cumulative feed depth of the tool within the wall thickness range of the second metal cladding layer 3, the tool can be effectively prevented from penetrating the second metal cladding layer 3.

[0083] In some embodiments of the present application, the first milling cutter may be configured as a tungsten steel milling cutter.

[0084] In some embodiments of the present application, after the second milling hole 32 is formed by the punching device 200, the tool can be withdrawn from the second milling hole 32, and the clamping of the CICC conductor 100 by the conductor clamp 5 can be released, thereby facilitating the separation of the punching device 200 from the CICC conductor 100 to further perform step five.

[0085] In step 5 of the embodiment of the present application, the operator can further process the second milling hole 32 using a handheld electric grinder to remove the remaining stainless steel skin of the second metal cladding layer 3 in the second milling hole 32 until the first metal cladding layer 2 appears. It should be emphasized that the straight and arc areas of the second milling hole 32 need to be precisely removed and carefully inspected.

[0086] After exposing the first metal cladding layer 2, the operator punctures the first metal layer with a tungsten steel stylus and then uses oblique needle-nose pliers to remove the second metal cladding layer 3 and the first metal cladding layer 2 from the second milling hole 32, thereby completing the machining of the superconducting magnet helium hole 10. It should be noted that the above manual operation can be repeated to ensure that the first metal cladding layer 2 and the second metal cladding layer 3 are effectively removed.

[0087] Combine Figure 6and Figure 9 As shown, it should be noted that, during the processing of the superconducting magnet helium hole 10, the second milling holes 32 can be first formed on multiple sections of the helium hole region transition section conductor 20 using the drilling device 200, or after multiple second milling holes 32 are formed on the same helium hole region transition section conductor 20, the drilling device 200 is lifted away, so that an operator can manually clean the roots of each of the multiple second milling holes 32, thereby further improving the processing efficiency of the superconducting magnet helium hole 10.

[0088] Combine Figures 1-10 The following describes the processing of the superconducting magnet helium hole 10 according to a specific embodiment of the present application:

[0089] An infrared level is used to guide the helium hole machining centerline to the surface of the transition section conductor 20 in the helium hole area of the CICC conductor 100 and mark it. The transfer error is controlled within 1mm. A drawing stylus is used in conjunction with a positioning tool to mark the length and width dimensions of the superconducting magnet helium hole 10.

[0090] Install the punching device 200, adjust the position of the milling device 6 using the adjustment device in the punching device 200, and after the position adjustment is completed, fix the milling device 6 to the base body 4, and further clamp and fix the conductor 20 of the transition section of the helium hole area using the conductor clamp 5;

[0091] Install the first milling cutter to the universal side milling head 63, and the deviation between the diameter of the first milling cutter and the diameter of the superconducting magnet helium hole 10 is ≤0.2mm. Move the first milling cutter to the starting point of the drilling, which is the edge of the line marking the helium hole;

[0092] Feed the first milling cutter at a speed of 3000 rpm, and when the scale on the punching device 200 indicates that the punching depth has increased by 0.3 mm (i.e., the first feed depth value mentioned above), control the first milling cutter to mill horizontally to the first position on the drawing line, and feed the first milling cutter at a speed of 3000 rpm again, and when the scale on the punching device 200 indicates that the punching depth has increased by 0.3 mm (i.e., the second feed depth value mentioned above), control the first milling cutter to mill horizontally to the second position, wherein this step can be repeated until the cumulative feed depth dimension of the first milled hole 31 reaches a preset value and milling is stopped;

[0093] Further, the first milling cutter is continued to be fed at a speed of 3000 rpm, and the single feed depth of the first milling cutter is 0.1 mm (i.e., the aforementioned third feed depth value), and the first milling cutter is further controlled to mill horizontally to the second position. Then, the first milling cutter is controlled to feed a single feed depth of 0.2 mm (i.e., the aforementioned fourth feed depth value) at the same speed of 3000 rpm, and then the first milling cutter is further controlled to mill horizontally to the first position. This step can be repeated until an obvious visible crack appears at the second metal cladding layer 3, and the milling is immediately stopped.

[0094] Replace the tool with the second milling cutter 7, adjust the second milling cutter 7 to form a depression angle with the horizontal plane, then move the second milling cutter 7 to the root position above the first milling hole 31, start milling the root depth of the first milling hole 31, and the single feed depth shall not exceed 0.1mm. Then adjust the second milling cutter 7 to form an elevation angle with the horizontal plane, and move the second milling cutter 7 to the root position below the first milling hole 31, and start milling the root depth of the first milling hole 31, and the single feed depth shall not exceed 0.1mm, so as to form the second milling hole 32;

[0095] The drilling equipment 200 is dismantled, and the operator forms the superconducting magnet helium hole 10 on the CICC conductor 100 by manual back-cutting.

[0096] The method for processing the superconducting magnet helium hole 10 of the CICC conductor 100 according to the embodiment of the present application has at least the following advantages compared with the prior art:

[0097] (1) The punching device 200 is clamped and cooperated with the CICC conductor 100, which can prevent the CICC conductor 100 from shaking during the machining process and ensure the hole machining accuracy. In addition, during the punching process, multiple tools (i.e., the first milling cutter and the second milling cutter 7) cooperate to process the root of the hole structure formed by rough machining, so as to remove local material at the root position of the superconducting magnet helium hole 10, thereby reducing the difficulty of subsequent manual root cleaning and helping to improve the root cleaning efficiency;

[0098] (2) During the milling process of the first milling cutter, the single feed amount of the first milling cutter is adjusted to prevent the first milling cutter from penetrating the second metal cladding layer 3 and causing damage to the cable body 1, thereby effectively reducing the risk of damage to the cable body 1 and improving the reliability of the processing process of the superconducting magnet helium hole 10.

[0099] Reference Figure 11 As shown, Figure 11 1 and 2 , a coil winding production line 1000 is shown, which is used to process a CICC conductor 100 into a superconducting coil.

[0100] The coil winding production line 1000 includes: a rotary platform and mold 210, an automatic control console 300, a bending and forming device 400, a conductor support device 500, a sandblasting cleaning device 600, an ultrasonic cleaning device 700, a conductor straightening device 800, and a conductor feeding device 900.

[0101] Specifically, the conductor feeding device 900 can be used to feed the conductor to be processed at a constant feed speed, and the conductor straightening device 800 is used to straighten the conductor and further transport it to the side of the ultrasonic cleaning device 700 and the sandblasting cleaning device 600, so that the straightened conductor can be ultrasonically cleaned by the ultrasonic cleaning device 700 and further sandblasted and cleaned by the sandblasting cleaning device 600.

[0102] Furthermore, the conductor after sandblasting cleaning can be transported to the side of the bending and forming device 400, and multiple sets of conductor support devices 500 are arranged between the bending and forming device 400 and the sandblasting cleaning device 600 to support the conductor on the transport path through the conductor support devices 500.

[0103] The bending and forming device 400 measures the conductor feed length and bends the conductor according to the coil's contour. The rotating platform and die 210 track the coil's winding trajectory, drop the conductor into the die, and bear the coil's weight. The rotating platform work surface and winding die within the rotating platform and die 210 control the coil's flatness and contour.

[0104] Reference Figure 11 An automatic control console 300 is also provided in the coil winding production line 1000. The automatic control console 300 can be used to communicate with other devices in the coil winding production line 1000 (such as: bending and forming device 400, sandblasting cleaning device 600, ultrasonic cleaning device 700, conductor straightening device 800, conductor feeding device 900, etc.) to realize automatic control of other devices.

[0105] It should be noted that the above-mentioned conductor is the CICC conductor 100. When processing the superconducting magnet helium hole 10 on the CICC conductor 100, the punching device 200 can be arranged at a circumferential outer position of the rotating platform and the mold 210 to perform a punching process on the CICC conductor 100 arranged on the rotating platform and the mold 210.

[0106] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0107] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0108] In the description of this application, “plurality” means two or more.

[0109] In the description of the present application, a first feature being “on” or “under” a second feature may include the first and second features being in direct contact with each other, or the first and second features being in contact with each other not directly but via another feature therebetween.

[0110] In the description of this application, a first feature “on”, “above” and “above” a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0111] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0112] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for machining a helium hole in a superconducting magnet of a CICC conductor, characterized in that: The CICC conductor includes a cable body and a first metal cladding layer and a second metal cladding layer sequentially covering the cable body. The processing method includes the following steps: Step 1: Marking the position of the helium hole of the superconducting magnet on the CICC conductor; Step 2: Mounting the CICC conductor on a punching device, so that the punching device clamps and fixes the helium hole transition section conductor in the CICC conductor, and aligning the first milling cutter on the punching device with the starting point of the helium hole in the superconducting magnet; Step 3: After adjusting the rotation speed of the first milling cutter to a preset constant value, controlling the feed of the first milling cutter to mill the second metal cladding layer to form a first milling hole, and visible cracks appear on the wall surface of the second metal cladding layer at the first milling hole; Step 4: replacing the first milling cutter in the punching device with a second milling cutter, adjusting the pitch angle of the second milling cutter relative to the first milling hole, and controlling the feed of the second milling cutter to mill the second metal cladding layer to form a second milling hole; Step 5: Lift out the drilling device and remove the remaining portion of the second metal cladding layer and the first metal cladding layer by manual root cleaning to form the superconducting magnet helium hole that sequentially penetrates the second metal cladding layer and the first metal cladding layer.

2. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 1, wherein: The step 1 also includes: An infrared level is used to accurately transfer the position of the superconducting magnet helium hole to the helium hole region transition section conductor, and the size of the superconducting magnet helium hole is marked on the helium hole region transition section conductor.

3. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 1, wherein: The punching device comprises a base, a conductor clamp and a milling device, wherein the conductor clamp is provided on the base and is used to clamp and fix the conductor of the transition section of the helium hole region in step 2. The position of the milling device is adjustable and provided on the base. In step 2, the following steps are further included: After the milling device is adjusted to be parallel to the conductor of the transition section in the helium hole region, the conductor of the transition section in the helium hole region is clamped and fixed by the conductor clamp.

4. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 3, wherein: The milling device has a universal side milling head, and the universal side milling head is used to install the first milling cutter or the second milling cutter. In the step 4, the following steps are also included: The universal side milling head is adjusted to adjust the pitch angle of the second milling cutter relative to the first milling hole.

5. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 3, wherein: In the step three, controlling the first milling cutter to feed to mill the second metal cladding layer to form a first milling hole includes: After controlling the punching device to feed the first milling cutter located at the starting point to a first feed depth value, controlling the first milling cutter to mill horizontally to a first position; After the first milling cutter is milled horizontally to a first position, the punching device is controlled to feed the first milling cutter to a second feed depth value, and then the first milling cutter is controlled to mill horizontally to a second position; wherein, The second position and the starting point coincide with each other in the feeding direction of the first milling cutter, and the first milling cutter can be controlled to perform reciprocating milling between the first position and the second position.

6. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 5, characterized in that: The helium hole of the superconducting magnet is an oblong hole, and the first position and the second position are edge positions on both sides of the oblong hole in the length direction respectively.

7. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 5, wherein: In the step 3, after the cumulative feed amount of the first milling cutter during the reciprocating milling process between the first position and the second position reaches a preset value, Controlling the first milling cutter to the first position, and after feeding at a third feed depth value, controlling the first milling cutter to mill horizontally to a second position; After the first milling cutter is milled horizontally to the second position, the punching device is controlled to feed the first milling cutter to a fourth feed depth value, and then the first milling cutter is controlled to mill horizontally to the first position; wherein, The first milling cutter can be controlled to reciprocate and feed milling between the first position and the second position, the fourth feed depth value is not less than the third feed depth value, and the third feed depth value and the fourth feed depth value are both less than the first feed depth value and the second feed depth value.

8. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 7, wherein: The first feed depth value is 0.3 mm, the second feed depth value is 0.3 mm, the third feed depth is 0.1 mm, and the fourth feed depth is 0.2 mm.

9. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 1, wherein: The second milling cutter is a dovetail milling cutter. In step 4, adjusting the pitch angle of the second milling cutter relative to the first milling hole includes: Adjusting the second milling cutter to form a depression angle with respect to the horizontal plane, and moving the second milling cutter to the root position of the upper portion of the first milling hole; The second milling cutter is adjusted to form an elevation angle with respect to a horizontal plane, and the second milling cutter is moved to a root position below the first milling hole.

10. The method for machining a helium hole in a superconducting magnet of a CICC conductor according to claim 9, wherein: In the step 4, controlling the second milling cutter to feed to mill the second metal cladding layer to form a second milling hole includes: The single feed depth of the second milling cutter is controlled to be no greater than 0.1 mm.

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