阅读说明：本技术 超导方形细线的接头结构及制作方法 (Joint structure of superconducting square thin wire and manufacturing method thereof ) 是由 魏本刚 焦婷 李柱永 金之俭 李红雷 于 2021-06-28 设计创作，主要内容包括：本发明提供了一种超导方形细线的接头结构及制作方法,包括：方形细线、切割截面和热缩管；所述方形细线末端切割出所述切割截面；多根所述方形细线两两通过所述切割截面贴合连接并通过所述热缩管包套固定；所述方形细线包套所述热缩管处通过灌锡镀锡构成方形细线接头。本发明避免了金属管包套带来的结构上的冗余,更易于扭绞、拉伸和弯曲,从外观上看来没有明显的接头部分。(The invention provides a joint structure of a superconducting square fine wire and a manufacturing method thereof, wherein the joint structure comprises the following steps: a square thin wire, a cut section and a heat shrink tube; cutting the cutting section at the tail end of the square fine line; every two of the square thin wires are jointed and connected through the cutting section and fixed through the heat-shrinkable tube sleeve; the square fine wire sheath is wrapped at the heat shrinkage pipe and is tinned through tin filling to form a square fine wire joint. The invention avoids the structural redundancy brought by the metal pipe sheath, is easier to twist, stretch and bend, and has no obvious joint part in appearance.)

1. A joint structure of a superconducting square thin wire, comprising: a square thin line, a cutting section (5) and a heat shrink tube (7);

-cutting said cutting section (5) at the end of said square string;

every two of the square thin wires are jointed and connected through the cutting section (5) and are sheathed and fixed through the heat-shrinkable tube (7);

the square fine wire sheath is arranged at the position of the heat shrinkable tube (7) and forms a square fine wire joint through tin filling and tinning.

2. A joint structure of a superconducting square thin wire according to claim 1, characterized in that said square thin wire comprises a copper tape (1) and a superconducting tape (2);

and a plurality of copper strips (1) are stacked on two sides of the superconducting tape (2).

3. The joint structure of a superconducting square thin wire according to claim 1, characterized in that: the cross section of the square thin line is set to be square, and the side length of the cross section of the square thin line is set to be (6).

4. A joint structure of a superconducting square thin wire according to claim 3, characterized in that: the included angle of cutting cross section (5) and top surface sets up to cutting offset angle (3), the included angle of cutting cross section (5) and side sets up to cutting angle of inclination (4).

5. The joint structure of a superconducting square thin wire according to claim 4, characterized in that: calculating the area S of the cut section (5) according to the formula:

wherein t is the side length (6) of the cross section of the square thin wire, A is the cutting deviation angle (3), and gamma is the cutting inclination angle (4).

6. The joint structure of a superconducting square thin wire according to claim 5, characterized in that: the cutting inclination angle (4) is 0 DEG without affecting the mechanical strength of the square thin wire; under the principle that the marginal benefit of the cutting offset angle (3) on the area S is maximized, the cutting offset angle (3) is 20-30 degrees.

7. The joint structure of a superconducting square thin wire according to claim 6, characterized in that: and after the heat shrinkable tube (7) is sheathed, the heat shrinkable tube (7) is heated to improve the mechanical strength of the square fine wire joint.

8. The joint structure of a superconducting square thin wire according to claim 7, characterized in that: and the square fine wire wraps the heat shrink tube (7) for tin filling and tin plating and scraping redundant tin solder.

9. The joint structure of a superconducting square thin wire according to claim 8, characterized in that: when the square thin wire is broken, the square thin wire is replaced by removing the heat shrinkable tube (7) and melting the soldering tin.

10. A method of manufacturing a joint structure of a superconducting square thin wire according to claim 9, comprising the steps of:

step S1, calculating the cutting mode of the cutting section (5);

step S2, cutting the cutting section (5) at the tail end of the square thin line and splicing the cutting sections (5) together in pairs;

step S3, fixing the spliced part by sheathing the heat shrinkable tube (7) and heating the heat shrinkable tube (7);

and step S4, the square fine wire wraps the heat shrinkable tube (7) to be tinned, and the redundant soldering tin is scraped, so that the square fine wire joint is manufactured.

Technical Field

The present invention relates to a superconducting tape, and more particularly, to a joint structure of a superconducting square thin wire and a method of manufacturing the same.

Background

In recent years, high-temperature superconducting materials have been rapidly applied to the field of power systems, such as superconducting cables, superconducting energy storage, superconducting transformers, superconducting current limiters, and superconducting motors. However, in the application process of superconducting power equipment, in order to meet the current demand of the equipment, the current capacity of a superconducting material needs to be continuously improved; in the working process of the power equipment, the alternating current loss generated when the superconducting material is interfered by external magnetic fields in different degrees needs to be reduced, so that the heating and system refrigeration burden of the equipment is reduced, and the stability of the power equipment is improved; and in some engineering applications, the superconducting material needs to be twisted, bent and stretched, and the superconducting tape needs to have certain mechanical strength. Therefore, to meet the three requirements, the common methods used in the industry for this problem include narrowing and twisting. In addition, stacking superconducting tapes can improve the current carrying capacity of the wire rod on one hand and can also improve the physical strength on the other hand. In summary, a plurality of second-generation high-temperature superconducting tapes (and other metal material tapes with the same width) with the width of 0.5-4 mm are stacked through filament narrowing and stacking packaging to form a high-temperature superconducting square thin wire made of a multilayer structure conductor, so that the electromagnetic property and the mechanical property of the wire can be improved at the same time, and the structure can be well suitable for actual power equipment.

However, in practical applications, such a high-temperature superconducting thin square wire needs to reach a certain length, but due to the limitation of the current superconducting tape manufacturing process, a single superconducting tape is usually tens of meters to hundreds of meters in length, while a high-temperature superconducting thin square wire is composed of tens of superconducting tapes, and it is very difficult to prepare a superconducting tape of this order of hundreds of meters in length. Therefore, to achieve a sufficient length, a joint is inevitable for a square thin wire.

Patent document CN110060817A relates to a high-temperature superconducting stacked narrow-band long-line preparation device and a working method thereof, which comprises a conveying mechanism, a soldering-assisting groove, a tin plating mechanism and a storage reel which are sequentially arranged; wherein the tinning mechanism comprises: a tin furnace; the fixing mechanism corresponds to the tin furnace in position; the transmission assembly is arranged on the fixing mechanism.

Patent document CN111872539A discloses an inner sealing joint for high temperature superconducting tapes, which is made to solve the technical problems of low joint strength, thickness difference between the joint and the original tape, uneven surface, poor mechanical properties and bending properties, etc. existing in the existing welding process after the high temperature superconducting tapes are packaged.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a joint structure of a superconducting square thin wire and a manufacturing method thereof.

According to the present invention, there is provided a joint structure of a superconducting square thin wire, comprising: a square thin wire, a cut section and a heat shrink tube;

cutting the cutting section at the tail end of the square fine line;

every two of the square thin wires are jointed and connected through the cutting section and fixed through the heat-shrinkable tube sleeve;

the square fine wire sheath is wrapped at the heat shrinkage pipe and is tinned through tin filling to form a square fine wire joint.

Preferably, the square thin wire comprises a copper strip and a superconducting strip;

and a plurality of copper strips are stacked on two sides of the superconducting strip.

Preferably, the cross section of the square thin line is set to be square, and the side length of the cross section of the square thin line is set to be the side length of the cross section of the square thin line.

Preferably, the included angle between the cutting section and the top surface is set as a cutting offset angle, and the included angle between the cutting section and the side surface is set as a cutting inclination angle.

Preferably, the area S of the cut section is calculated according to the formula:

wherein t is the side length of the cross section of the square thin wire, A is the cutting offset angle, and gamma is the cutting inclination angle.

Preferably, the larger the cutting inclination angle, the larger the area S, but the larger the cutting inclination angle, the lower the mechanical strength of the square thin wire, the cutting inclination angle being 0 ° without affecting the mechanical strength of the square thin wire; the larger the cutting offset angle is, the larger the area S is, the larger the cutting offset angle is, the longer the square thin wire joint is, and the cutting offset angle is 20 ° to 30 ° on the principle that the marginal benefit of the cutting offset angle to the area S is maximized, that is, the principle that the unit increment of the cutting offset angle contributes most to the increase of the area S.

Preferably, after the heat shrinkable tube is sheathed, the heat shrinkable tube is heated to improve the mechanical strength of the square fine wire joint.

Preferably, the square thin wire is connected with the outer side of the heat shrinkable tube and is subjected to tin filling and tin plating, and excess tin is scraped.

Preferably, when the square thin wire is broken, the square thin wire is replaced by removing the heat shrinkable tube and the solder.

The invention also provides a manufacturing method of the joint structure of the superconducting square fine wire, which comprises the following steps:

step S1, calculating the cutting mode of the cutting section;

step S2, cutting the cutting sections at the tail ends of the square thin lines and splicing the cutting sections together two by two;

step S3, fixing the spliced part through the heat shrinkable tube sheath and heating the heat shrinkable tube;

and step S4, performing tin filling and tinning on the position where the square fine wire wraps the heat-shrinkable tube, and scraping redundant tin solder, wherein the square fine wire joint is manufactured completely.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention avoids the structural redundancy brought by the metal pipe sheath, is easier to twist, stretch and bend, and has no obvious joint part in appearance;

2. the invention avoids the complex distribution of current among the superconducting tapes of different layers in the 'inner sealing joint'.

3. The joint manufactured by the invention has larger contact area, smaller resistance value and larger heat dissipation area.

4. The joint structure provided by the invention is convenient to manufacture and is beneficial to disassembly and reassembly.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic view of a structure of a superconducting square fine wire joint structure;

FIG. 2 is a schematic diagram of a square thin line structure;

FIG. 3 is a schematic view of a cut section structure;

FIG. 4 is a schematic view of a heat shrink tube wrap retaining fitting;

shown in the figure:

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

Example 1

As shown in fig. 1 and 4, a joint structure of a superconducting square thin wire includes: square fine rule, cutting cross-section 5 and pyrocondensation pipe 7, square fine rule end cut out cutting cross-section 5, and two liang of many square fine rules are connected and are fixed through 7 canning of pyrocondensation pipe through 5 laminating of cutting cross-section, and 7 departments of square fine rule canning pyrocondensation pipe constitute square fine rule joint through tin-filling tin-plating. After the heat shrinkable tube 7 is sheathed, the heat shrinkable tube 7 is heated to improve the mechanical strength of the square fine wire joint, and the square fine wire sheathed heat shrinkable tube 7 is tinned by tin filling and is scraped to remove redundant tin soldering. When the square thin wire is broken, the square thin wire is replaced by removing the heat shrinkable tube 7 and melting the solder.

As shown in fig. 2 and 3, the square thin wire includes a copper tape 1 and a superconducting tape 2, and a plurality of copper tapes 1 are stacked on both sides of the superconducting tape 2. The cross section of the square thin wire is set to be square, the side length of the cross section of the square thin wire is set to be 6, the included angle between the cutting section 5 and the top surface is set to be 3, and the included angle between the cutting section 5 and the side surface is set to be 4. The area S of the cut section 5 is calculated according to the formula:wherein t is the side length 6 of the cross section of the square thin line, A is a cutting offset angle 3, and gamma is a cutting inclination angle 4. The area S is larger when the cutting inclination angle 4 is larger, but the mechanical strength of the square thin wire is lower when the cutting inclination angle 4 is larger, under the condition that the mechanical strength of the square thin wire is not influenced, the cutting inclination angle 4 is 0 degrees, the area S is larger when the cutting offset angle 3 is larger, the square thin wire joint is longer when the cutting offset angle 3 is larger, and under the principle that the marginal benefit of the cutting offset angle 3 to the area S is maximized, namely the principle that the increment of the cutting offset angle 3 is the largest in contribution to the increase of the area S, the cutting offset angle 3 is 20 degrees to 30 degrees.

The invention also provides a manufacturing method of the joint structure of the superconducting square fine wire, which comprises the following steps:

step S1, calculating a cutting mode of the cut section 5;

step S2, cutting the cutting section 5 at the end of the square thin line and splicing the cutting sections 5 together two by two;

step S3, fixing the spliced part by sheathing the heat shrinkable tube 7 and heating the heat shrinkable tube 7;

and step S4, tin filling and tinning are carried out on the position, where the square fine wire wraps the heat-shrinkable tube 7, and excessive tin solder is scraped off, so that the square fine wire joint is manufactured.

Example 2

The invention mainly provides a novel joint preparation process based on the existing second-generation high-temperature superconducting tape and high-temperature superconducting square thin wires, two high-temperature superconducting square thin wires are butted after being obliquely cut along the longitudinal direction, and are tinned and packaged after being sleeved with a heat shrink tube 7. The problem of current interior sealing joint preparation degree of difficulty be big, can't utilize the joint to adorn again after dismantling it when a certain section square line bad point appears is solved. Aiming at the manufacture of the joint of the high-temperature superconducting square thin wire, the invention provides a brand new preparation method which comprises the following steps: and butting two high-temperature superconducting square thin wires to be connected after longitudinally beveling, and performing tin filling and packaging after sheathing the heat-shrinkable tube 7. The method has simple manufacturing process, is convenient to disassemble and reassemble when a certain section of square thin wire has a defective pixel, and has larger contact area, smaller resistance value of the connector and larger heat dissipation area compared with other connector connectors.

As shown in fig. 3, the cutting process at the square fine line joint: putting two high-temperature superconducting square thin wires into a mould according to a mathematical formulaThe cutting inclination angle is 0 degree under the condition of not influencing the mechanical strength of the wire; according to the principle that the marginal benefit of the cutting offset angle 3 to the sectional area is maximized, the cutting offset angle 3 is about 25 degrees, and the tail end of the square thin wire is cut;

as shown in fig. 4, the heat shrinkable tube 7 encloses: butting two cut high-temperature superconducting square wires, sheathing and fixing the two high-temperature superconducting square wires by using a heat-shrinkable tube 7, and heating the heat-shrinkable tube 7 by using a hot air gun to ensure that the joint has certain mechanical strength;

as shown in fig. 1, the tin-filling process: filling tin into the square thin wire sleeved with the heat shrinkable tube 7 by using a tin furnace, tinning, removing redundant liquid tin by using a scraper, cooling, and bundling by using a guide wheel to finish the preparation of the square thin wire with the connector;

disassembling: if a certain section of the square thin wire has a dead spot and needs to be replaced, the heat-shrinkable tube 7 is damaged and removed, the dead spot section wire is placed in a tin furnace again for soaking, and the perfect superconducting section can be installed again after the soldering tin at the joint is completely dissolved.

The high-temperature superconducting square thin wire is composed of several superconducting tapes, and it is very difficult to prepare superconducting tapes many hundreds of meters long due to the limitation of the superconducting production process. Therefore, in the long-line manufacturing process of the square thin line, a joint is inevitable. Some joints are usually made by sheathing a welded metal tube, and this method still has many challenges, such as not being favorable for twisting and stretching of the wires and complicated manufacturing process. In order to improve the disadvantages, in the process of stacking and packaging the square thin wires, some joints are formed by overlapping a single superconducting tape to reach a target length, and then stacking and packaging a plurality of superconducting tapes containing overlapping joints, so as to realize the lengthening and linearization of the superconducting stacked wire. However, due to factors such as the resistance of the lap joint of each superconducting layer, the arrangement of joints of different layers and the like, when the stacked wires are in through-flow, the distribution of current in different superconducting layers is affected, and further, the square thin wire presents a complex resistance characteristic.

The novel joint mode provided by the invention avoids the structural redundancy brought by the metal pipe sheath, is easier to twist, stretch and bend, has no obvious joint part in appearance, and simultaneously avoids the complex distribution of current among the superconducting tapes of different layers in the 'inner sealing joint'. And the joint structure that this patent provided makes conveniently, does benefit to dismantlement and repacking.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.