Superconducting cable shrink tube tool and forming process thereof

Abstract

This invention discloses a superconducting cable tube shrinking fixture and its forming process. Mounted on a lathe, the lathe includes a chuck, an apron, and a tailstock. The superconducting cable tube shrinking fixture, mounted on the apron, includes a frame-shaped support with two symmetrically arranged tube shrinking rollers inside. The space between the two rollers allows the superconducting cable to pass through. The frame-shaped support also includes an adjusting block for adjusting the distance between the two rollers. The forming process includes steps such as passing the superconducting cable through the two rollers. This invention has a simple structure, is easy to use, and is low in cost. It effectively meets the tube shrinking requirements of superconducting cables, and the fixture can be reused multiple times, offering high efficiency.

Description

Technical Field

[0001] This invention belongs to the field of superconducting conductor manufacturing technology, specifically relating to a superconducting cable tube shrinking tool and its forming process. Background Technology

[0002] Currently, in the manufacturing process of superconducting cables, a spiral-shaped superconducting wire needs to be placed inside a T2 copper tube or a 316L stainless steel tube before undergoing a tube shrinking process. After shrinking, the superconducting wire is embedded in the tube wall. If an ordinary tube shrinking machine is used, it cannot meet the requirement of spiraling the superconducting wire inside the tube. If the superconducting wire is pre-twisted into a spiral shape, it is extremely inconvenient to thread it through the tube, making it difficult to meet the tube shrinking requirements of superconducting cables. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides a superconducting cable tube shrinking tool and its forming process, which is reliable in forming and easy to operate.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A superconducting cable tube shrinking fixture is installed on a lathe. The lathe includes a chuck, an apron, and a tailstock. The superconducting cable tube shrinking fixture is installed on the apron and includes a frame-shaped support. Two tube shrinking rollers are symmetrically arranged inside the frame-shaped support. The space between the two tube shrinking rollers is formed for the superconducting cable to pass through. The frame-shaped support is also provided with an adjusting block to adjust the distance between the two tube shrinking rollers.

[0006] Furthermore, the adjusting block is C-shaped, with a shrinking roller embedded in its open side, and a set screw on the closed side of the adjusting block. The set screw passes through the outside of the frame bracket, pushing the adjusting block to move and lock within the frame bracket.

[0007] Furthermore, the shrinking roller is hourglass-shaped, and the radius of the end face where it contacts the adjusting block is larger than its central radius.

[0008] This invention also provides a superconducting cable forming process, which uses the above-mentioned superconducting cable shrinking tool to form a superconducting cable, including the following steps:

[0009] (1) Cleaning of superconducting wires;

[0010] (2) Annealing of T2 copper tubes or 316L stainless steel tubes;

[0011] (3) Tightly bind the stranded superconducting wire and insert it into a T2 copper tube or a 316L stainless steel tube.

[0012] (4) Place the two shrinking rollers tightly against the T2 copper pipe or 316L stainless steel pipe.

[0013] (5) Start the lathe, gradually increase the chuck speed, maintain the feed rate of the slide box and gradually reduce the distance between the tube shrinking rollers.

[0014] This invention has a simple structure, is easy to use, and is inexpensive. It can effectively meet the requirements of superconducting cable tube shrinking and superconducting wire spiral forming. The tooling can be reused multiple times and has the advantage of high efficiency.

[0015] The molding process described in this invention can strictly control the tube shrinkage effect of the superconducting cable, meeting the high standards and strict requirements for the use of the superconducting cable under vacuum conditions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the superconducting cable tube shrinking tool of the present invention. Detailed Implementation

[0018] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0019] Example 1

[0020] The superconducting cable shrinking fixture provided in Example 1 is installed on a C616A lathe. The C616A lathe includes a chuck, a tool post, and a tailstock. The tool post is mounted on the apron. After removing the tool post, it can be inserted into the superconducting cable shrinking fixture. Figure 1 As shown, the superconducting cable shrinking fixture includes a frame bracket 1, with two shrinking rollers 2 symmetrically arranged inside the frame bracket 1. The space between the two shrinking rollers 2 is formed for the superconducting cable to pass through. The frame bracket 1 is also provided with an adjusting block 3 for adjusting the distance between the two shrinking rollers 2.

[0021] During tube shrinking, a strand of superconducting wire is first inserted linearly into a T2 copper tube or a 316L stainless steel tube. One end of the tube filled with superconducting wire is clamped in a chuck, and the other end is passed between two shrinking rollers 2 and then rested on the tailstock of the lathe. After starting the lathe, the chuck rotates the T2 copper tube, and by reducing the distance between the shrinking rollers 2, tube shrinking and helical forming of the superconducting wire inside the tube can be achieved. The superconducting wire can be Bi-2212 superconducting wire, niobium-titanium superconducting wire, copper wire mixed with other superconducting wires, or YBCO superconducting wire, etc.

[0022] During the tube shrinking process, the T2 copper tube or 316L stainless steel tube is twisted together with the superconducting wire. Due to the lower strength of the T2 copper tube or 316L stainless steel tube, in the annealed state, the tensile strength of the T2 copper tube is 200-300 MPa, and the elongation after fracture is 45%-50%; the tensile strength of the 316L stainless steel tube is 480-550 MPa, and the elongation after fracture is 30%. Moreover, the yield strength of the T2 copper tube and 316L stainless steel tube is low, so there will be no springback after forming, thus ensuring that the process performance after tube shrinking will not be affected.

[0023] Example 2

[0024] In Example 2, based on Example 1, the adjusting block 3 is C-shaped, and the shrinking roller 2 is embedded in the open side of the adjusting block 3. The closed side of the adjusting block 3 is provided with a set screw 4, which passes through the outside of the frame bracket 1. After pushing the adjusting block 3 to the appropriate position in the track inside the frame bracket 1, it is locked. The purpose is to have the advantages of strong operability and stable structure.

[0025] Example 3

[0026] In Example 3, based on Example 2, the shrinking roller 2 is hourglass-shaped, and the radius of the end face where it connects with the adjusting block 3 is larger than its central radius. The purpose is to ensure that when the two shrinking rollers 2 work together, they can better tighten the superconducting cable.

[0027] Example 4

[0028] This invention provides a superconducting cable forming process, which uses the superconducting cable tube shrinking tooling in Example 1 to perform superconducting cable tube shrinking forming, including the following steps:

[0029] (1) Clean the niobium-titanium superconducting wire with a diameter of 0.73 mm with deionized water;

[0030] (2) Anneal the T2 copper tube with a diameter of 23mm and a wall thickness of 1.2mm;

[0031] (3) Tightly bind the stranded niobium-titanium superconducting wire and insert it into the T2 copper tube;

[0032] (4) Clamp one end of the T2 copper tube filled with niobium-titanium superconducting wires (about 260 wires) on the chuck of the C616A lathe, and put the other end through the two tube shrinking rollers 2 of the superconducting cable shrinking tool and then on the tailstock.

[0033] (5) Adjust the superconducting cable shrinking tool so that both shrinking rollers 2 are in close contact with the copper tube.

[0034] (6) Start the lathe and adjust the spindle speed to 19 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two tube shrinking rollers 2 0.02 mm toward the center;

[0035] (7) Adjust the spindle speed to 28 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two tube shrinking rollers 2 0.02 mm toward the center;

[0036] (8) Adjust the spindle speed to 40 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two shrinking rollers 2 0.02 mm toward the center;

[0037] (9) Adjust the spindle speed to 51 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two shrinking rollers 2 0.02 mm toward the center;

[0038] (10) Adjust the spindle speed to 74 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two shrinking rollers 2 0.02 mm toward the center.

[0039] Tests revealed that the diameter of the T2 copper tube had decreased by 2 mm, and the niobium-titanium superconducting wire was spiral-shaped.

[0040] Example 5

[0041] This invention provides another superconducting cable forming process, which uses the superconducting cable tube shrinking tooling in Example 1 to perform superconducting cable tube shrinking forming, including the following steps:

[0042] (1) Clean the Bi-2212 superconducting wire with a diameter of 1.0 mm with deionized water;

[0043] (2) Annealing a 316L stainless steel tube with a diameter of 23mm and a wall thickness of 1.5mm;

[0044] (3) Tightly bind the stranded Bi-2212 superconducting wire and insert it into the 316L stainless steel tube;

[0045] (4) Clamp one end of the 316L stainless steel tube filled with Bi-2212 superconducting wires (about 42 wires) on the chuck of the C616A lathe, and put the other end through the two tube shrinking rollers 2 of the superconducting cable shrinking tool and then on the tailstock.

[0046] (5) Adjust the superconducting cable shrinking tool so that both shrinking rollers 2 are in close contact with the copper tube.

[0047] (6) Start the lathe and adjust the spindle speed to 19 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two tube shrinking rollers 2 0.02 mm toward the center;

[0048] (7) Adjust the spindle speed to 28 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two tube shrinking rollers 2 0.02 mm toward the center;

[0049] (8) Adjust the spindle speed to 40 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two shrinking rollers 2 0.02 mm toward the center;

[0050] (9) Adjust the spindle speed to 51 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two shrinking rollers 2 0.02 mm toward the center;

[0051] (10) Adjust the spindle speed to 74 r / min and the feed rate to 0.03 mm / r; turn the adjusting block 3 to move each of the two shrinking rollers 2 0.02 mm toward the center.

[0052] Tests revealed that the diameter of the 316L stainless steel tube was reduced by 2mm, and the Bi-2212 superconducting wire was spiral-shaped.

[0053] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A superconducting cable collapsing tool, characterized by: The device is installed on a lathe, which includes a chuck, an apron, and a tailstock. The superconducting cable shrinking fixture is installed on the apron and includes a frame bracket. Two shrinking rollers are symmetrically arranged inside the frame bracket. The space between the two shrinking rollers is formed for the superconducting cable to pass through. The frame bracket is also provided with an adjusting block to adjust the distance between the two shrinking rollers. During tube shrinking, the superconducting wire strands are first inserted into a T2 copper tube or a 316L stainless steel tube in a straight line. One end of the tube filled with superconducting wire is clamped on a chuck, and the other end is passed between two shrinking rollers and placed on the tailstock of the lathe. After the lathe is turned on, the chuck drives the T2 copper tube or 316L stainless steel tube to rotate. Then, by reducing the distance between the shrinking rollers, the tube shrinking and the spiral forming of the superconducting wire inside the tube are achieved.

2. The superconducting cable-in-conduit field assembly of claim 1, wherein: The adjusting block is C-shaped, with a shrinking roller embedded in its open side. The closed side of the adjusting block is provided with a set screw, which passes through the outside of the frame bracket and pushes the adjusting block to move and lock within the frame bracket.

3. The superconducting cable tube shrinking fixture according to claim 1 or 2, characterized in that: The shrinking roller is hourglass-shaped, and the radius of the end face where it connects with the adjusting block is larger than its central radius.

4. A superconducting cable forming process, using the superconducting cable shrinking fixture as described in claim 1, 2, or 3 to form the superconducting cable, characterized in that: Includes the following steps: (1) Cleaning of superconducting wires; (2) Annealing of T2 copper tubes or 316L stainless steel tubes; (3) Tightly bind the stranded superconducting wire and insert it into a T2 copper tube or a 316L stainless steel tube; (4) Place the two shrinking rollers tightly against the T2 copper pipe or 316L stainless steel pipe; (5) Start the lathe, gradually increase the chuck speed, maintain the feed rate of the slide box and gradually reduce the distance between the tube shrinking rollers.

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