High-conductivity aluminum alloy core reinforced insulation overhead cable

Abstract

The invention discloses a high-conductivity aluminum alloy core reinforced insulated overhead cable, which comprises a conductor, a shielding layer and an insulating layer, and is prepared from an ethylene-vinyl acetate copolymer, linear low-density polyethylene, magnesium hydroxide, ammonium polyphosphate, pentaerythritol, nano silicon dioxide, light calcium carbonate, a silane coupling agent and an antioxidant. And mixing with a lubricant and carrying out extrusion molding to prepare the cable insulation layer. Through reasonable material selection and formula design, the high-conductivity aluminum alloy core reinforced insulating aerial cable has high conductivity, excellent flame retardance, environmental protection property and mechanical strength, is suitable for being used in various complex environments, and meets the performance requirements and environmental protection standards of modern cables.

Description

Technical Field

[0001] The invention relates to the technical field of cable manufacturing, in particular to a high-conductivity aluminum alloy core reinforced insulation overhead cable. Background Art

[0002] In the construction of overhead transmission lines, the cable's conductivity and insulation reliability directly determine grid transmission efficiency and operational safety. While traditional aluminum alloy core overhead cables enhance their mechanical strength through the addition of elements like magnesium and silicon, they suffer from two key flaws. First, conventional insulation layers often utilize polyvinyl chloride (PVC) or cross-linked polyethylene (XLPE), whose formulations contain halogenated flame retardants (such as decabromodiphenyl ether), which release toxic fumes and corrosive gases in fires, violating green grid environmental protection requirements. Second, existing insulation systems struggle to balance structural stability under high-temperature conditions with long-term wear resistance. Prolonged exposure to sunlight and windy conditions can cause surface microcracks due to UV aging and grit impact, increasing the risk of partial discharge. Furthermore, to match the expansion coefficient of the aluminum alloy core, traditional insulation layers often sacrifice an upper temperature limit (typically below 90°C). This can lead to softening and deformation of the insulation when overload current causes the cable to heat up, accelerating structural degradation. Furthermore, it fails to simultaneously optimize both halogen-free flame retardancy and wear resistance. Summary of the Invention

[0003] The present invention aims to provide a high-conductivity aluminum alloy core reinforced insulated overhead cable, which realizes that the cable insulation layer is environmentally friendly, highly flame-retardant, high-temperature resistant and wear-resistant. From the inside to the outside, the cable insulation layer comprises a conductor, a shielding layer and an insulating layer. The insulating layer comprises the following components in weight percentage: 25-40% of ethylene-vinyl acetate copolymer, 10-20% of linear low-density polyethylene, 20-28% of magnesium hydroxide, 5-10% of ammonium polyphosphate, 3-5% of pentaerythritol, 3-7% of nano-silica, 5-10% of light calcium carbonate, 0.3-1.0% of a silane coupling agent, 0.5-1.5% of an antioxidant and 0.3-1.0% of a lubricant.

[0004] Furthermore, the magnesium hydroxide is 200 mesh to 400 mesh.

[0005] Furthermore, the ratio of pentaerythritol to ammonium polyphosphate is 1:2 to 1:3.

[0006] Furthermore, the silane coupling agent is 3-aminopropyltriethoxysilane, which can improve the compatibility between the polymer and the filler.

[0007] Furthermore, the antioxidant is tris(2,4-di-tert-butylphenyl)phosphite, which is an environmentally friendly antioxidant suitable for high-performance polymers to provide long-term protection.

[0008] Furthermore, the lubricant is soybean oil, a plant-based lubricant. As a natural plant-based lubricant, soybean oil has good lubrication properties and meets environmental protection requirements. Furthermore, the steps of preparing the insulating layer include the following: Step 1: Prepare the ingredients Accurately weigh each ingredient to ensure accuracy; Step 2: Mixing Using a high-speed mixer, ethylene-vinyl acetate copolymer and linear low-density polyethylene are placed into the mixer and preliminarily mixed; Then add magnesium hydroxide, ammonium polyphosphate, pentaerythritol, nano silicon dioxide, light calcium carbonate, silane coupling agent, antioxidant and lubricant, and continue mixing; Mix for 10 to 20 minutes to ensure that all ingredients are evenly distributed; Step 3: Extrusion The mixed materials are fed into a twin-screw extruder. The temperature of the extruder is set: the temperature of the feeding zone is set to 80-120°C, and the temperature of the plasticizing zone is set to 160-200°C. Through the rotation of the screw, the materials are plasticized and evenly mixed, and then extruded through the mold. Step 4: Cold Cuts After extrusion, the material should be immediately cooled through a cooling water trough to avoid overheating and degradation of material properties; the water temperature of the cooling water trough should be controlled at 20-30°C to ensure rapid cooling.

[0009] The beneficial effects of the present invention are embodied in: The use of environmentally friendly flame retardant materials such as magnesium hydroxide and ammonium polyphosphate can effectively inhibit the spread of flames and increase the safety of cables in fire situations, meeting the fire safety requirements of modern architecture and industry; the addition of nano-silicon dioxide improves the mechanical strength and wear resistance of the insulation layer, enhances the impact resistance of the cable, and is suitable for use in harsh environments; the selection of low-toxic, renewable materials (such as plant-based lubricant soybean oil) reduces the impact on the environment, which is in line with the development trend of green environmental protection; the use of environmentally friendly antioxidants (such as tris (2,4-di-tert-butylphenyl) phosphite) provides long-term antioxidant protection and extends the service life of the cable; due to its excellent performance, the cable is suitable for overhead power transmission, communications and other fields, meeting the needs of different applications; the high-conductivity aluminum alloy core reinforced insulated overhead cable of the present invention has high conductivity, excellent flame retardancy, environmental protection and mechanical strength through reasonable material selection and formula design, is suitable for use in various complex environments, and meets the performance requirements and environmental protection standards of modern cables. DETAILED DESCRIPTION

[0010] The present invention is further described below with reference to the following examples. The examples are not intended to limit the scope of the present invention. Modifications or substitutions made to the methods, steps, or conditions of the present invention without departing from the essence of the technical solution of the present invention are within the scope of the present invention.

[0011] Unless otherwise specified, the equipment, devices and process methods used in the examples are conventional equipment, devices and process methods well known to those skilled in the art.

[0012] In the following embodiments and comparative examples, the thickness of the insulating layer is 3.4 mm.

[0013] Example 1

[0014] Step 1: Prepare the ingredients Accurately weigh the weight of each component to ensure accuracy, and weigh 25% of ethylene-vinyl acetate copolymer, 10% of linear low-density polyethylene, 20% of 300-mesh magnesium hydroxide, 6% of ammonium polyphosphate, 3% of pentaerythritol, 3% of nano-silica, 5% of light calcium carbonate, 0.3% of 3-aminopropyltriethoxysilane, 0.5% of tris(2,4-di-tert-butylphenyl)phosphite, and 0.3% of soybean oil; Step 2: Mixing Using a high-speed mixer, 25% of ethylene-vinyl acetate copolymer and 10% of linear low-density polyethylene were placed into the mixer for preliminary mixing; Then add 20% magnesium hydroxide, 6% ammonium polyphosphate, 3% pentaerythritol, 3% nano-silica, 5% light calcium carbonate, 0.3% 3-aminopropyltriethoxysilane, 0.5% tris(2,4-di-tert-butylphenyl)phosphite, and 0.3% soybean oil, and continue mixing; mix for 20 minutes to ensure that all ingredients are evenly distributed; Step 3: Extrusion The mixed materials are fed into a twin-screw extruder. The temperature of the extruder is set: the temperature of the feeding zone is set to 100°C, and the temperature of the plasticizing zone is set to 180°C. Through the rotation of the screw, the materials are plasticized and evenly mixed, and then extruded through the mold to form; Step 4: Cold Cuts After extrusion, the material should be immediately cooled through a cooling water trough to avoid overheating and degradation of material properties; the water temperature of the cooling water trough should be controlled at 25°C to ensure rapid cooling.

[0015] Example 2

[0016] Step 1: Prepare the ingredients Accurately weigh the weight of each component to ensure accuracy, and weigh 30% of ethylene-vinyl acetate copolymer, 13% of linear low-density polyethylene, 22% of 300-mesh magnesium hydroxide, 8% of ammonium polyphosphate, 4% of pentaerythritol, 4% of nano-silica, 7% of light calcium carbonate, 0.5% of 3-aminopropyltriethoxysilane, 1% of tris(2,4-di-tert-butylphenyl)phosphite, and 0.5% of soybean oil; Step 2: Mixing Using a high-speed mixer, 30% of ethylene-vinyl acetate copolymer and 13% of linear low-density polyethylene were placed into the mixer for preliminary mixing; Then add 22% magnesium hydroxide, 8% ammonium polyphosphate, 4% pentaerythritol, 4% nano-silica, 7% light calcium carbonate, 0.5% 3-aminopropyltriethoxysilane, 1% tris(2,4-di-tert-butylphenyl)phosphite, and 0.5% soybean oil, and continue mixing; mix for 20 minutes to ensure that all ingredients are evenly distributed; Step 3: Extrusion The mixed materials are fed into a twin-screw extruder. The temperature of the extruder is set: the temperature of the feeding zone is set to 100°C, and the temperature of the plasticizing zone is set to 180°C. Through the rotation of the screw, the materials are plasticized and evenly mixed, and then extruded through the mold to form; Step 4: Cold Cuts After extrusion, the material should be immediately cooled through a cooling water trough to avoid overheating and degradation of material properties; the water temperature of the cooling water trough should be controlled at 25°C to ensure rapid cooling.

[0017] Example 3

[0018] Step 1: Prepare the ingredients Accurately weigh the weight of each component to ensure accuracy, and weigh 35% of ethylene-vinyl acetate copolymer, 15% of linear low-density polyethylene, 25% of 300-mesh magnesium hydroxide, 10% of ammonium polyphosphate, 5% of pentaerythritol, 5% of nano-silica, 10% of light calcium carbonate, 1% of 3-aminopropyltriethoxysilane, 1% of tris(2,4-di-tert-butylphenyl)phosphite, and 1% of soybean oil; Step 2: Mixing Using a high-speed mixer, 35% of ethylene-vinyl acetate copolymer and 15% of linear low-density polyethylene were placed into the mixer for preliminary mixing; Then add 25% magnesium hydroxide, 10% ammonium polyphosphate, 5% pentaerythritol, 5% nano-silica, 10% light calcium carbonate, 1% 3-aminopropyltriethoxysilane, 1% tris(2,4-di-tert-butylphenyl)phosphite, and 1% soybean oil, and continue mixing; mix for 20 minutes to ensure that all ingredients are evenly distributed; Step 3: Extrusion The mixed materials are fed into a twin-screw extruder. The temperature of the extruder is set: the temperature of the feeding zone is set to 100°C, and the temperature of the plasticizing zone is set to 180°C. Through the rotation of the screw, the materials are plasticized and evenly mixed, and then extruded through the mold to form; Step 4: Cold Cuts After extrusion, the material should be immediately cooled through a cooling water trough to avoid overheating and degradation of material properties; the water temperature of the cooling water trough should be controlled at 25°C to ensure rapid cooling.

[0019] Example 4

[0020] Step 1: Prepare the ingredients Accurately weigh the weight of each component to ensure accuracy, and weigh 40% of ethylene-vinyl acetate copolymer, 20% of linear low-density polyethylene, 28% of 300-mesh magnesium hydroxide, 10% of ammonium polyphosphate, 5% of pentaerythritol, 7% of nano-silica, 10% of light calcium carbonate, 1% of 3-aminopropyltriethoxysilane, 1.5% of tris(2,4-di-tert-butylphenyl)phosphite, and 1% of soybean oil; Step 2: Mixing Using a high-speed mixer, 40% of ethylene-vinyl acetate copolymer and 20% of linear low-density polyethylene were placed into the mixer for preliminary mixing; Then add 28% magnesium hydroxide, 10% ammonium polyphosphate, 5% pentaerythritol, 7% nano-silica, 10% light calcium carbonate, 1% 3-aminopropyltriethoxysilane, 1.5% tris(2,4-di-tert-butylphenyl)phosphite, and 1% soybean oil, and continue mixing; mix for 20 minutes to ensure that all ingredients are evenly distributed; Step 3: Extrusion The mixed materials are fed into a twin-screw extruder. The temperature of the extruder is set: the temperature of the feeding zone is set to 100°C, and the temperature of the plasticizing zone is set to 180°C. Through the rotation of the screw, the materials are plasticized and evenly mixed, and then extruded through the mold to form; Step 4: Cold Cuts After extrusion, the material should be immediately cooled through a cooling water trough to avoid overheating and degradation of material properties; the water temperature of the cooling water trough should be controlled at 25°C to ensure rapid cooling.

[0021] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

Claims

1. A high conductivity aluminum alloy core reinforced insulated overhead cable, characterized in that: From the inside to the outside, there are conductors, shielding layers, and insulating layers. The insulating layer includes the following components in weight percentage: 25-40% ethylene-vinyl acetate copolymer, 10-20% linear low-density polyethylene, 20-28% magnesium hydroxide, 5-10% ammonium polyphosphate, 3-5% pentaerythritol, 3-7% nano-silicon dioxide, 5-10% light calcium carbonate, 0.3-1.0% silane coupling agent, 0.5-1.5% antioxidant, and 0.3-1.0% lubricant.

2. A high conductivity aluminum alloy core reinforced insulated overhead cable according to claim 1, characterized in that: The magnesium hydroxide is 200-400 meshes.

3. The high conductivity aluminum alloy core reinforced insulated overhead cable according to claim 1, characterized in that: The ratio of pentaerythritol to ammonium polyphosphate is 1:2 to 1:

3.

4. The high conductivity aluminum alloy core reinforced insulated overhead cable according to claim 1, characterized in that: The silane coupling agent is 3-aminopropyltriethoxysilane, which can improve the compatibility between the polymer and the filler.

5. The high conductivity aluminum alloy core reinforced insulated overhead cable according to claim 1, characterized in that: The antioxidant is tris(2,4-di-tert-butylphenyl)phosphite, which is an environmentally friendly antioxidant suitable for high-performance polymers and provides long-term protection.

6. The high conductivity aluminum alloy core reinforced insulated overhead cable according to claim 1, characterized in that: The lubricant is soybean oil, a plant-based lubricant. Soybean oil, as a natural plant-based lubricant, has good lubricating properties and meets environmental protection requirements.

7. The high conductivity aluminum alloy core reinforced insulated overhead cable according to claim 1, characterized in that: The steps of preparing the insulating layer include the following: Step 1: Prepare the ingredients Accurately weigh each ingredient to ensure accuracy; Step 2: Mixing Using a high-speed mixer, ethylene-vinyl acetate copolymer and linear low-density polyethylene are placed into the mixer and preliminarily mixed; Then add magnesium hydroxide, ammonium polyphosphate, pentaerythritol, nano silicon dioxide, light calcium carbonate, silane coupling agent, antioxidant and lubricant, and continue mixing; Mix for 10 to 20 minutes to ensure that all ingredients are evenly distributed; Step 3: Extrusion The mixed materials are fed into a twin-screw extruder. The temperature of the extruder is set: the temperature of the feeding zone is set to 80-120°C, and the temperature of the plasticizing zone is set to 160-200°C. Through the rotation of the screw, the materials are plasticized and evenly mixed, and then extruded through the mold. Step 4: Cold Cuts After extrusion, the material should be immediately cooled through a cooling water trough to avoid overheating and degradation of material properties; the water temperature of the cooling water trough should be controlled at 20-30°C to ensure rapid cooling.