High-voltage cable with good weather resistance

Abstract

The invention relates to the technical field of cables, and discloses a high-voltage cable with good weather resistance, which comprises a tin-copper wire core, a conductive silicone rubber layer coated on the outer side of the tin-copper wire core and an insulating silicone rubber layer coated on the outer side of the conductive silicone rubber layer, and the sectional area of the tin-copper wire core is 2.5 mm < 2 >. According to the high-voltage cable provided by the invention, through the synergistic interaction of the passivated tin-copper wire cores and the multi-layer silicone rubber structure, the comprehensive performance is remarkably optimized, and meanwhile, the high-voltage cable has the advantages of excellent high-temperature and low-temperature resistance, excellent electrical insulation performance, excellent chemical stability, high voltage resistance, aging resistance and long service life, and is soft and convenient to install.

Description

Technical Field

[0001] The invention relates to the technical field of cables, in particular to a high-voltage cable with good weather resistance. Background Art

[0002] With the rapid development of power transmission and high-voltage application technologies, high-voltage cables, as core components, have increasingly stringent performance requirements. Traditional high-voltage cables are mostly made of materials such as polyvinyl chloride (PVC) or cross-linked polyethylene (XLPE). Although they have certain insulation properties, they are prone to hardening and cracking in extreme temperature environments, resulting in insufficient weather resistance. For example, high temperature environments may accelerate material aging and reduce insulation performance, while low temperature environments will reduce the flexibility of cables, affecting installation and use. In addition, existing cables are prone to partial discharge or breakdown under long-term high-voltage loads, posing safety hazards, and have poor chemical stability. They are easily corroded in corrosive environments, shortening their service life. For scenarios such as high-voltage testers and neon lights that require frequent bending or complex wiring, the rigid structure of traditional cables also limits their applicability.

[0003] In response to the above problems, the industry urgently needs a high-voltage cable solution that is both weather-resistant, highly insulating and flexible. Although there are attempts to use silicone rubber to improve temperature resistance in the prior art, its comprehensive performance is still difficult to meet the long-term stability requirements in high-voltage DC application scenarios. Therefore, developing a high-voltage cable that can maintain flexibility in a wide temperature range of -60°C to 200°C, and has excellent electrical insulation, anti-aging ability and chemical stability, has become a key technical direction for improving the reliability and safety of related equipment. Summary of the invention

[0004] The object of the present invention is to provide a high voltage cable with good weather resistance, which solves the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a high-voltage cable with good weather resistance, comprising a tin-copper core, a conductive silicone rubber layer coated on the outside of the tin-copper core, and an insulating silicone rubber layer coated on the outside of the conductive silicone rubber layer, wherein the cross-sectional area of ​​the tin-copper core is 2.5mm 2 .

[0006] Preferably, the tin-copper wire core needs to be passivated. After the tin-copper wire core is electrolytically cleaned, it passes through a passivation liquid tank containing benzotriazole to form a nano-scale protective film.

[0007] Preferably, the passivated tin-copper wire core directly enters the high-temperature extruder, and the conductive silicone rubber layer is coated before the protective film is completely cured to enhance the interface bonding force.

[0008] Preferably, the conductive silicone rubber layer is formed by mixing a highly conductive material and a silicone rubber material, wherein the ratio of the highly conductive material to the silicone rubber material is 3:7.

[0009] Preferably, the highly conductive material is silver powder.

[0010] Preferably, the insulating silicone rubber layer is made of a mixture of high-carbon powder material and silicone rubber material, wherein the ratio of the high-carbon powder material to the silicone rubber material is 1:9.

[0011] Preferably, the wire diameter of the conductive silicone rubber layer is 2.80 mm - 3.00 mm, the minimum thickness of the conductive silicone rubber layer is 0.32 mm, and its average thickness is 0.40 mm.

[0012] Preferably, the wire diameter of the insulating silicone rubber layer is 5.70 mm - 6.10 mm, the average thickness of the insulating silicone rubber layer is 1.40 mm, and its minimum thickness is 1.12 mm.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] The high-voltage cable provided by the present invention synergistically enhances the performance through the passivated tin-copper wire core and the multi-layer silicone rubber structure, and the comprehensive performance is significantly optimized. The tin-copper wire core is treated with benzotriazole passivation solution to form a nano-protective film, combined with the high-temperature extrusion process, which greatly improves the corrosion resistance and interface bonding strength; the conductive silicone rubber layer is compounded with silver powder and silicone rubber to ensure high conductivity, and the insulating layer is compounded with high-carbon powder and silicone rubber to endow excellent electrical insulation and anti-aging characteristics; the cable remains flexible at extreme temperatures from -60°C to 200°C, the wire diameter and thickness are precisely matched, taking into account the voltage withstand strength and installation convenience, completely solving the defects of traditional materials such as high-temperature brittle cracking, low-temperature hardening and easy breakdown, and the service life is extended by more than 30%. Description of the Drawings

[0015] Figure 1 It is a sectional view of the present invention.

[0016] The reference numerals and names in the drawings are as follows:

[0017] 1. Tin-copper wire core; 2. Conductive silicone rubber layer; 3. Insulating silicone rubber layer. Detailed Embodiments

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "horizontal", "vertical", "top", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0020] Please refer to Figure 1 , an embodiment provided by the present invention: a high-voltage cable with good weather resistance, and its preparation method includes the following steps:

[0021] Step 1: Preparation and passivation treatment of the tin-copper wire core 1

[0022] Material selection: Select a tin-copper alloy wire with a tin content of 5%. The cross-sectional area of the tin-copper wire core 1 is strictly controlled at 2.5 mm 2 to ensure the balance between current-carrying capacity and mechanical strength.

[0023] Electrolytic cleaning: Immerse the tin-copper wire core 1 in an alkaline electrolyte solution (pH = 10 - 12), and conduct electrolytic cleaning for five minutes to remove the surface oxide layer and impurities.

[0024] Passivation treatment: Use an aqueous passivation solution containing 1.5% benzotriazole (BTA), control the temperature of the passivation tank at 45°C, and soak for 10 minutes to form a dense protective film with a thickness of about 50 nm on the surface of the tin-copper wire core 1. This film can significantly inhibit the migration of copper ions and improve the corrosion resistance.

[0025] High-temperature extrusion process linkage: The passivated tin-copper wire core 1 is directly fed into a twin-screw high-temperature extruder (temperature set at 180°C), and the conductive silicone rubber layer 2 is coated before the protective film is completely cured, using the thermal bonding property of silicone rubber to enhance the interfacial bonding force.

[0026] Step 2: Preparation of the conductive silicone rubber layer 2

[0027] Material ratio: The conductive silicone rubber layer 2 is composed of silver powder (particle size ≤ 10 μm) and silicone rubber (methyl vinyl silicone rubber, VMQ) mixed in a mass ratio of 3:7, and kneaded in a mixer at 120°C for 20 minutes to ensure uniform dispersion.

[0028] Coating process: The mixture is continuously coated on the surface of the passivated tin-coated copper wire core 1 through a high-temperature extruder, controlling the extrusion pressure at 15 MPa and the wire speed at 2 m / min, so that the wire diameter of the conductive silicone rubber layer 2 is stabilized at 2.80 mm - 3.00 mm, and the average thickness is 0.40 mm (the minimum thickness is 0.32 mm). This design takes into account both conductivity (volume resistivity ≤ 0.01 Ω·cm) and flexibility.

[0029] Step 3: Preparation of the insulating silicone rubber layer 3

[0030] Material ratio: The insulating silicone rubber layer 3 is composed of high-carbon powder (graphitized carbon black, particle size ≤ 5 μm) and silicone rubber (VMQ) mixed in a mass ratio of 1:9, with a kneading temperature of 110 °C and a kneading time of 15 minutes.

[0031] Coating process: Using a double-layer co-extrusion technology, the insulating layer is simultaneously coated outside the conductive layer, controlling the extrusion temperature at 170 °C, the wire diameter range at 5.70 mm - 6.10 mm, and the average thickness at 1.40 mm (the minimum thickness is 1.12 mm). The density of the insulating layer is 1.25 g / cm 3 , and the breakdown voltage ≥ 35 kV / mm, meeting the high-voltage insulation requirements.

[0032] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A high-voltage cable with good weather resistance, characterized in that: It includes a tin-copper wire core, a conductive silicone rubber layer coated on the outer side of the tin-copper wire core, and an insulating silicone rubber layer coated on the outer side of the conductive silicone rubber layer. Among them, the cross-sectional area of the tin-copper wire core is 2.5mm 2 .

2. The high-voltage cable with good weather resistance according to claim 1, wherein: The tin-copper wire core needs to be passivated. After electrolytic cleaning, the tin-copper wire core passes through a passivation liquid tank containing benzotriazole to form a nano-level protective film.

3. The high-voltage cable with good weather resistance according to claim 2, wherein: The passivated tin-copper wire core directly enters a high-temperature extruder, and the conductive silicone rubber layer is coated before the protective film is completely cured to enhance the interfacial bonding force.

4. A high-voltage cable with good weather resistance according to claim 1, characterized in that: The conductive silicone rubber layer is composed of a high-conductivity material and a silicone rubber material. Among them, the ratio of the high-conductivity material to the silicone rubber material is 3:

7.

5. The high-voltage cable with good weather resistance according to claim 4, wherein: The high-conductivity material is silver powder.

6. A high-voltage cable with good weather resistance according to claim 1, characterized in that: The insulating silicone rubber layer is composed of a high-carbon powder material and a silicone rubber material. Among them, the ratio of the high-carbon powder material to the silicone rubber material is 1:

9.

7. A high-voltage cable with good weather resistance according to any one of claims 1 to 5, characterized in that: The wire diameter of the conductive silicone rubber layer is 2.80 mm - 3.00 mm, and the minimum thickness of the conductive silicone rubber layer is 0.32 mm, with an average thickness of 0.40 mm.

8. A high-voltage cable with good weather resistance according to any one of claims 1, 2, 3 or 6, characterized in that: The wire diameter of the insulating silicone rubber layer is 5.70 mm - 6.10 mm, the average thickness of the insulating silicone rubber layer is 1.40 mm, and its minimum thickness is 1.12 mm.

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