CICC conductor axial tension testing device

Abstract

The invention relates to the technical field of CICC conductor tensile testing, in particular to a CICC conductor axial tensile testing device which comprises a first clamping mechanism, a second clamping mechanism, a screw rod and a strain gauge, the first clamping mechanism is clamped at one end of a CICC conductor, the second clamping mechanism is clamped at the other end of the CICC conductor, and the screw rod is connected with the strain gauge. One end of the screw rod is in threaded connection with the first clamping mechanism, the other end of the screw rod is in threaded connection with the second clamping mechanism, the screw rod is used for adjusting the distance between the first clamping mechanism and the second clamping mechanism, and a strain gauge is arranged on the CICC conductor. The resistance of the contact surface of the sample and the clamp is not increased, and the sample needs to have enough length which is not a necessary condition of the testing device, so that the testing device is higher in universality.

Description

Technical Field

[0001] The present invention relates to the technical field of CICC conductor tensile testing, and in particular to a CICC conductor axial tensile testing device. Background Art

[0002] Since Dutch scientists first discovered the superconducting phenomenon in which the resistance of mercury suddenly disappears at a temperature of about 4.2K, after more than a century of exploration and research, scientists have identified hundreds of materials with superconducting properties. Among these materials, those that can be put into commercial applications can be roughly divided into two categories: low-temperature superconducting materials and high-temperature superconducting materials. Low-temperature superconducting materials mainly include metal alloys such as Nb3Sn and NbTi, which exhibit superconducting properties under specific low-temperature conditions. High-temperature superconducting materials, especially the REBCO (rare earth barium copper oxide) series, have become one of the most widely used high-temperature superconducting materials in current projects due to their excellent performance at higher critical magnetic fields and critical current densities, as well as their good mechanical properties.

[0003] In order to promote the commercialization of magnetic confinement fusion energy, the miniaturization of fusion reactors is currently a recognized technical route in the world, which requires cables made of superconducting materials to work under higher currents (greater than 60kA) and stronger magnetic field environments (greater than 20T). Under the operating conditions of high magnetic fields and high currents, the magnets will be subjected to huge electromagnetic loads, which may cause brittle fracture of the material at low temperatures and structural damage under the action of multiple fields. If a superconductor loses its superconducting state, its resistance will increase dramatically, which will cause serious damage to the magnet and may lead to huge economic losses.

[0004] During the operation of superconducting magnets, the electromagnetic load on the cable usually manifests itself as forces in two orthogonal directions: one is the hoop tension along the conductor axis (parallel to the current direction), and the other is the lateral load along the radial direction of the coil (perpendicular to the current direction). In order to simulate the operating conditions of the magnet in a real magnetic field, it is necessary to apply a load to the cable sample while measuring the critical current. Since it is too expensive to test directly on superconducting coils, such tests are usually performed through straight conductor structures. However, the lateral load on the straight conductor test is the lateral Lorentz force generated by the magnetic field of the test device and the current of the sample itself, which cannot provide the axial strain during operation, such as the problem faced by the SULTAN test device in Switzerland.

[0005] Existing superconducting tensile testing equipment uses copper block clamps to fix the object to be tested at both ends of the cable, and applies axial strain through threaded support rods. At the same time, these copper blocks also act as terminals for current to flow into the conductor. However, there are two main problems with this design: 1. When the sample is fixed with a clamp, the applied force may cause the sample to deform, increasing the resistance of the contact surface between the sample and the clamp, which is not conducive to the current flowing into the conductor. 2. In order to ensure that the current flows completely through the superconducting material, the sample must be of sufficient length. However, as the length of the sample increases, the tensile force applied at both ends will produce different strains at different positions of the sample, which may cause errors in the experimental results.

[0006] Currently, how to prevent the clamp from directly stretching the CICC conductor and thereby obtain the accurate behavior of the influence of the tensile strain on the cable has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0007] The present invention provides a CICC conductor axial tension test device, which is used to solve the problem of how to avoid the clamp directly stretching the CICC conductor, and then obtain the accurate behavior of the influence of the tensile strain on the cable.

[0008] The present invention provides a CICC conductor axial tensile test device, comprising: a first clamping mechanism; A second clamping mechanism; the first clamping mechanism is clamped at one end of the CICC conductor, and the second clamping mechanism is clamped at the other end of the CICC conductor; Screw; one end of the screw is threadedly connected to the first clamping mechanism, and the other end is threadedly connected to the second clamping mechanism, and is used to adjust the distance between the first clamping mechanism and the second clamping mechanism; Among them, a strain gauge is arranged on the CICC conductor.

[0009] In some embodiments, the first clamping mechanism includes a first upper clamping plate and a first lower clamping plate, and the first upper clamping plate and the first lower clamping plate are connected by screws.

[0010] In some embodiments, the second clamping mechanism includes a second upper clamping plate and a second lower clamping plate, and the second upper clamping plate and the second lower clamping plate are connected by screws.

[0011] In some embodiments, threads are formed at both ends of the screw, and the threads at the two ends are in opposite directions.

[0012] In some embodiments, there are two screws, one end of one screw is threadedly connected to the first upper clamping plate, and the other end is threadedly connected to the second upper clamping plate, and one end of the other screw is threadedly connected to the first lower clamping plate, and the other end is threadedly connected to the second lower clamping plate.

[0013] In some embodiments, the cross-sections of the first upper clamping plate, the first lower clamping plate, the second upper clamping plate, and the second lower clamping plate are all L-shaped.

[0014] In some embodiments, support plates are installed on the first upper clamping plate, the first lower clamping plate, the second upper clamping plate and the second lower clamping plate.

[0015] In some embodiments, the first upper clamping plate, the first lower clamping plate, the second upper clamping plate and the second lower clamping plate are all provided with clamping slots.

[0016] In some embodiments, the cross-section of the slot is semicircular.

[0017] In some embodiments, a torsion nut is sleeved on the screw rod.

[0018] The beneficial effects of the present invention are as follows: When testing the axial tensile performance of a CICC conductor, an axial tensile load is applied to the CICC conductor by synchronously twisting the screw, which is mainly adjusted by twisting the nut 1. This design allows the CICC conductor to be precisely stretched to simulate the stress conditions that may be encountered in actual use. By adjusting the screw, the size of the tensile load applied to the conductor can be controlled to simulate different working conditions. The strain gauge is a key component pasted in the middle of the CICC conductor and is used to measure the deformation of the conductor after being subjected to force. The final test result, that is, the relationship between the axial strain and the critical current of the conductor, is obtained by analyzing the data provided by the strain gauge. In the technical solution of the present invention, there is no need to fix the object to be tested from both ends of the CICC conductor, and the resistance of the contact surface between the sample and the fixture will not be increased. In addition, the sample having sufficient length is not a necessary condition for the test device of the present invention, which makes the test device of the present invention more versatile. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of some specific embodiments of a CICC conductor axial tensile testing device of the present invention; Figure 2 yes Figure 1 A schematic structural diagram of some specific embodiments of a slot in a CICC conductor axial tensile test device is shown; In the attached drawings, 1, torsion nut; 2, first upper clamping plate; 3, first lower clamping plate; 4, second upper clamping plate; 5, second lower clamping plate; 6, screw rod; 7, support plate; 8, slot; 9, strain gauge. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] At present, the existing technology will increase the contact resistance between the clamp and the cable due to the axial load when conducting the CICC conductor tensile test, which is not conducive to the flow of the conductor. At the same time, the distance between the two ends of the clamp is far, and the strain in the length direction of the cable is uneven, so it is impossible to obtain the accurate relationship between the cable and the strain. Therefore, how to avoid the clamp from directly stretching the CICC wire and then obtain the accurate behavior of the tensile strain on the cable has become a technical problem that needs to be solved by technicians in this field.

[0022] To solve the above problems, refer to Figure 1 and Figure 2 , the present invention provides a CICC conductor axial tensile testing device, a first clamping mechanism; A second clamping mechanism; the first clamping mechanism is clamped at one end of the CICC conductor, and the second clamping mechanism is clamped at the other end of the CICC conductor; Screw 6; one end of the screw is threadedly connected to the first clamping mechanism, and the other end is threadedly connected to the second clamping mechanism, and is used to adjust the distance between the first clamping mechanism and the second clamping mechanism; Wherein, a strain gauge 9 is provided on the CICC conductor; Specifically, the first clamping mechanism and the second clamping mechanism in the present invention stretch the CICC conductor by friction force, rather than directly clamping and stretching the CICC conductor from both ends in the prior art.

[0023] Preferably, the first clamping mechanism comprises a first upper clamping plate 2 and a first lower clamping plate 3, and the first upper clamping plate 2 and the first lower clamping plate 3 are connected by screws.

[0024] Preferably, the second clamping mechanism comprises a second upper clamping plate 4 and a second lower clamping plate 5, and the second upper clamping plate 4 and the second lower clamping plate 5 are connected by screws; Specifically, multiple groups of screws are provided and evenly distributed on both sides of the CICC conductor to ensure that the CICC conductor is evenly stressed.

[0025] Preferably, both ends of the screw rod 6 are provided with threads, and the directions of the threads at the two ends are opposite; Specifically, the user only needs to rotate the screw rod 6 to make the first clamping mechanism and the second holding mechanism move away from each other or towards each other, thereby achieving a stretching effect on the CICC wire.

[0026] Preferably, there are two screw rods 6, one end of one screw rod 6 is threadedly connected to the first upper clamping plate 2, and the other end is threadedly connected to the second upper clamping plate 4, and one end of the other screw rod 6 is threadedly connected to the first lower clamping plate 3, and the other end is threadedly connected to the second lower clamping plate 5.

[0027] Preferably, the cross-sections of the first upper clamping plate 2, the first lower clamping plate 3, the second upper clamping plate 4 and the second lower clamping plate 5 are all L-shaped; Specifically, the L-shaped clamping plate provides a mounting surface perpendicular to the clamping plate surface for the screw rod 6 and the screw.

[0028] Preferably, a support plate 7 is installed on each of the first upper clamping plate 2, the first lower clamping plate 3, the second upper clamping plate 4 and the second lower clamping plate 5; Specifically, the support plate 7 ensures that the force can act evenly on the clamp during the axial load loading process, while avoiding stress concentration at the intersection of the right-angled edges of the clamp, thereby protecting the structural integrity of the clamp.

[0029] Preferably, the first upper clamping plate 2 , the first lower clamping plate 3 , the second upper clamping plate 4 and the second lower clamping plate 5 are all provided with a clamping slot 8 .

[0030] Preferably, the cross section of the card slot 8 is semicircular; Specifically, the upper and lower groups of slots 8 form a complete circle, and the CICC conductor is clamped in the circle formed by the two groups of slots 8. Preferably, a torsion nut 1 is sleeved on the screw rod 6; Specifically, when in use, the nut only needs to be rotated to drive the screw rod 6 to rotate, thereby adjusting the tensile test device.

[0031] The present invention ensures the stability of the current lead by separating the fixture that applies axial tension from the current lead. At the same time, by shortening the distance between the length of the tested cable and the stretching fixture, the accurate degradation law of the performance of the cable critical current under the influence of axial strain is obtained. The device of the present invention can reduce the length of the tested sample, thus reducing the influence of the possible non-uniformity of the sample itself on the test result.

[0032] During the test, the axial stretching device and the current terminal are separated, so as to avoid the increase of the contact resistance of the current terminal due to the tensile force during the stretching process, thereby affecting the accuracy of the test results.

[0033] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0034] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0035] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean 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 invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0037] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A CICC conductor axial tensile test device, characterized in that: include: a first clamping mechanism; A second clamping mechanism; the first clamping mechanism is clamped at one end of the CICC conductor, and the second clamping mechanism is clamped at the other end of the CICC conductor; A screw rod (6); one end of the screw rod is threadedly connected to the first clamping mechanism, and the other end of the screw rod is threadedly connected to the second clamping mechanism, and is used to adjust the distance between the first clamping mechanism and the second clamping mechanism; Wherein, a strain gauge (9) is arranged on the CICC conductor.

2. A CICC conductor axial tensile test device according to claim 1, characterized in that: The first clamping mechanism comprises a first upper clamping plate (2) and a first lower clamping plate (3), and the first upper clamping plate (2) and the first lower clamping plate (3) are connected by screws.

3. A CICC conductor axial tensile test device according to claim 2, characterized in that: The second clamping mechanism comprises a second upper clamping plate (4) and a second lower clamping plate (5), and the second upper clamping plate (4) and the second lower clamping plate (5) are connected by screws.

4. A CICC conductor axial tensile test device according to claim 3, characterized in that: Both ends of the screw rod (6) are provided with threads, and the directions of the threads at the two ends are opposite.

5. The CICC conductor axial tensile test device according to claim 3, characterized in that: The number of the screw rods (6) is two, one end of one of the screw rods (6) is threadedly connected to the first upper clamping plate (2), and the other end is threadedly connected to the second upper clamping plate (4), and one end of the other screw rod (6) is threadedly connected to the first lower clamping plate (3), and the other end is threadedly connected to the second lower clamping plate (5).

6. The CICC conductor axial tensile test device according to claim 3, characterized in that: The cross-sections of the first upper clamping plate (2), the first lower clamping plate (3), the second upper clamping plate (4) and the second lower clamping plate (5) are all L-shaped.

7. A CICC conductor axial tensile test device according to claim 6, characterized in that: Support plates (7) are mounted on the first upper clamping plate (2), the first lower clamping plate (3), the second upper clamping plate (4) and the second lower clamping plate (5).

8. The CICC conductor axial tensile test device according to claim 3, characterized in that: The first upper clamping plate (2), the first lower clamping plate (3), the second upper clamping plate (4) and the second lower clamping plate (5) are all provided with clamping slots (8).

9. A CICC conductor axial tensile test device according to claim 8, characterized in that: The cross section of the clamping slot (8) is semicircular.

10. The CICC conductor axial tensile test device according to claim 1, characterized in that: A torsion nut (1) is sleeved on the screw rod (6).

Images