Medium voltage fire resistant aluminium alloy power cable

Abstract

The utility model discloses a kind of medium-voltage flame-retardant aluminum alloy power cable, belong to cable technical field, the cable includes conductor, the conductor is formed by multiple aluminum alloy wire core stranding, multiple aluminum alloy wire core between stranding gap is filled with multiple flame-retardant filling strip and buffer filling core, inner shielding layer is tightly wrapped in the outer peripheral surface of the conductor, insulating layer is extruded in the outer peripheral surface of the inner shielding layer, inner buffer layer is extruded in the outer peripheral surface of the insulating layer, outer shielding layer is tightly wrapped in the outer peripheral surface of the inner buffer layer, inner flame-retardant layer is wrapped in the outer peripheral surface of the outer shielding layer, armored layer is wound in the outer peripheral surface of the inner flame-retardant layer along helical direction, outer buffer layer is wrapped in the outer peripheral surface of the armored layer, outer flame-retardant layer is extruded in the outer peripheral surface of the outer buffer layer, the cable is borrowed multiple flame-retardant, double shielding uniform electric field, buffer structure anti-extrusion, effectively improve medium-voltage transmission security and stability.

Description

Technical Field

[0001] This utility model relates to the field of power cable technology, and more specifically, to a medium-voltage flame-retardant aluminum alloy power cable. Background Technology

[0002] In the current medium-voltage power transmission field, although aluminum alloy cables have advantages such as light weight and corrosion resistance, they suffer from three major defects: First, their flame-retardant structure is simple, with a single-layer sheath easily penetrated by flames, resulting in a high risk of insulation failure; second, the conductor and shielding layers have poor compatibility, with no targeted filling of the stranding gaps, leading to prominent issues of uneven electric field and signal interference; third, their compression resistance is insufficient, lacking a dedicated buffer structure, making them prone to insulation cracking and conductor misalignment under external pressure, thus compromising the synergy between flame retardancy and transmission function. Therefore, there is an urgent need to design a medium-voltage aluminum alloy power cable that integrates layered flame retardancy, structural compatibility, and buffer protection to address these comprehensive performance defects. Utility Model Content

[0003] To overcome the above shortcomings, this utility model provides a medium-voltage flame-retardant aluminum alloy power cable, which aims to improve the following issues: firstly, the flame-retardant structure is simple, the single-layer sheath is easily penetrated by flames, and the risk of insulation failure is high; secondly, the conductor and shielding layer have poor compatibility, the stranding gaps are not specifically filled, and the problems of uneven electric field and signal interference are prominent; and thirdly, the extrusion resistance is insufficient and there is a lack of a special buffer structure.

[0004] This utility model is implemented as follows: A medium-voltage flame-retardant aluminum alloy power cable includes a conductor, which is formed by stranding multiple aluminum alloy wire cores. Multiple flame-retardant filler strips and buffer filler cores are filled in the stranding gaps between the multiple aluminum alloy wire cores. The flame-retardant filler strips and buffer filler cores are arranged alternately. An inner shielding layer tightly wraps around the outer periphery of the conductor. An insulation layer is extruded around the outer periphery of the inner shielding layer. An inner buffer layer is extruded around the outer periphery of the insulation layer. An outer shielding layer tightly wraps around the outer periphery of the inner buffer layer. An inner flame-retardant layer is wrapped around the outer periphery of the outer shielding layer. An armor layer is spirally wound around the outer periphery of the inner flame-retardant layer. An outer buffer layer is wrapped around the outer periphery of the armor layer. An outer flame-retardant layer is extruded around the outer periphery of the outer buffer layer.

[0005] In a preferred embodiment of this utility model, the inner buffer layer is provided with a plurality of buffer holes, each of which has a diameter of 0.5-1.0 mm. The inner surface of the inner buffer layer is provided with arc-shaped protrusions, which are attached and fixed to the insulating layer. The inner buffer layer is made of elastic rubber. The buffer holes and the protrusions are staggered. The buffer holes are filled with flame-retardant elastic particles.

[0006] In a preferred embodiment of this utility model, the inner surface of the inner shielding layer is wavy, the overall thickness of the inner shielding layer is 0.8-1.2 mm, and the inner shielding layer is made of semi-conductive cross-linked polyethylene material.

[0007] In a preferred embodiment of this utility model, the thickness of the insulating layer is 3-5mm, and four axial positioning protrusions are evenly distributed along the circumferential direction on the outer surface of the insulating layer. The insulating layer is made of cross-linked polyethylene material.

[0008] In the preferred embodiment of this utility model, the thickness of the outer flame retardant layer is 2-4mm, and the outer surface of the outer flame retardant layer is uniformly distributed with diamond-shaped anti-slip textures. The outer flame retardant layer is a low-smoke halogen-free flame retardant polyolefin material.

[0009] In the preferred embodiment of this utility model, the outer buffer layer is a low-smoke halogen-free elastic strip, the cross-section of the outer buffer layer is corrugated, the height of the corrugated peaks is 0.8-1.2mm, the depth of the corrugated troughs is the same as the height of the peaks, and the overlapping part during wrapping accounts for 25-35% of the width of a single loop of the strip.

[0010] In a preferred embodiment of this utility model, the buffer filling core is a cylindrical elastomer with a diameter of 1.5-2.0 mm, and a plurality of hemispherical elastic protrusions are evenly distributed on the surface of the buffer filling core. The diameter of the protrusions is 0.3-0.4 mm, and the distance between two adjacent protrusions is 0.5-0.8 mm.

[0011] In the preferred embodiment of this utility model, the flame-retardant filler strip is a flame-retardant glass fiber rope with an elliptical cross-section. Its major axis length is consistent with the width of the conductor stranding gap, and the rope body has arc-shaped fitting surfaces on both sides that are adapted to the buffer filler core.

[0012] The beneficial effects of this utility model are: Significantly improved flame retardant performance, reducing the risk of insulation failure: Adopting a multi-layer flame retardant structure of "flame retardant filler strip + inner flame retardant layer + outer flame retardant layer", the flame retardant filler strip (flame retardant fiberglass rope) in the conductor stranding gap can initially block the spread of flame in the gap. The inner flame retardant layer and the outer flame retardant layer (low smoke halogen-free flame retardant polyolefin material, 2-4mm thick) form a layered protection, effectively avoiding the problem of single-layer sheath being easily penetrated by flames, greatly reducing the risk of insulation layer failure due to flame attack. At the same time, the low smoke halogen-free characteristics of the outer flame retardant layer also improve the safety and environmental protection of use.

[0013] More uniform electric field distribution and enhanced anti-interference capability: The inner shielding layer (semi-conductive cross-linked polyethylene material, with a wavy inner surface and a thickness of 0.8-1.2mm) and the outer shielding layer form a double shielding structure. Combined with the filling effect of the flame-retardant filler strip and the buffer filler core in the conductor stranding gap, the problem of poor compatibility between the conductor and the shielding layer is solved, so that the electric field is evenly distributed, significantly reducing signal interference and ensuring the stability of medium-voltage power transmission.

[0014] Optimized compression resistance and buffering performance to protect the internal structure: The buffer filling core (cylindrical elastomer with hemispherical protrusions on the surface) in the conductor gap can absorb local vibration and slight compression stress. The inner buffer layer (elastic rubber material with buffer holes filled with flame-retardant elastic particles) and the outer buffer layer (corrugated low-smoke halogen-free elastic strip with 0.8-1.2mm crests and troughs and 25-35% overlap) can absorb external compression impact layer by layer, effectively preventing insulation layer cracking and conductor misalignment, ensuring the synergy of the cable's flame retardancy and transmission function, and extending its service life. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of a medium-voltage flame-retardant aluminum alloy power cable provided by an embodiment of the present invention; Figure 2 A schematic diagram of the inner buffer layer is provided for the embodiment of this utility model.

[0017] In the diagram: 110 - conductor; 111 - flame-retardant filler strip; 112 - buffer filler core; 120 - inner shielding layer; 130 - insulation layer; 140 - inner buffer layer; 150 - outer shielding layer; 160 - inner flame-retardant layer; 170 - armor layer; 180 - outer buffer layer; 190 - outer flame-retardant layer. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0019] Please see Figure 1 and Figure 2 The present invention provides a technical solution: a medium-voltage flame-retardant aluminum alloy power cable, comprising a conductor 110, which is formed by stranding multiple aluminum alloy wire cores. Multiple flame-retardant filler strips 111 and buffer filler cores 112 are filled in the stranding gaps between the multiple aluminum alloy wire cores. The flame-retardant filler strips 111 and buffer filler cores 112 are arranged alternately. An inner shielding layer 120 is tightly wrapped around the outer periphery of the conductor 110. An insulation layer 130 is extruded around the outer periphery of the inner shielding layer 120. An inner buffer layer 140 is extruded around the outer periphery of the insulation layer 130. An outer shielding layer 150 is tightly wrapped around the outer periphery of the inner buffer layer 140. An inner flame-retardant layer 160 is wrapped around the outer periphery of the outer shielding layer 150. An armor layer 170 is wound spirally around the outer periphery of the inner flame-retardant layer 160. An outer buffer layer 180 is wrapped around the outer periphery of the armor layer 170. An outer flame-retardant layer 190 is extruded around the outer periphery of the outer buffer layer 180.

[0020] In some specific implementation schemes, the inner buffer layer 140 is provided with multiple buffer holes, each with a diameter of 0.5-1.0 mm. The inner surface of the inner buffer layer 140 is provided with arc-shaped protrusions, which are attached and fixed to the insulation layer 130. The inner buffer layer 140 is made of elastic rubber. The buffer holes and protrusions are staggered, and the buffer holes are filled with flame-retardant elastic particles. On the one hand, the arc-shaped protrusions can make the inner buffer layer 140 and the insulation layer 130 fit tightly and fix it, avoiding interlayer displacement; on the other hand, the buffer holes and the elastic rubber material work together to absorb external extrusion impact, and the flame-retardant elastic particles can also help improve local flame retardancy, effectively reducing the risk of the insulation layer 130 cracking due to external extrusion, while enhancing the overall impact resistance of the cable.

[0021] In some specific implementations, the inner surface of the inner shielding layer 120 is wavy, the overall thickness of the inner shielding layer 120 is 0.8-1.2mm, and the inner shielding layer 120 is made of semi-conductive cross-linked polyethylene material. The wavy inner surface can better fit the stranded outer circumference of the conductor 110, increase the contact area, and make the electric field uniformly distributed between the conductor 110 and the inner shielding layer 120, significantly reducing signal interference. This solves the problem of uneven electric field caused by poor compatibility between the conductor and the shielding layer of traditional cables, and ensures the stability of medium-voltage power transmission.

[0022] In some specific implementations, the insulation layer 130 has a thickness of 3-5mm. The outer surface of the insulation layer 130 has four axial positioning protrusions evenly distributed along the circumference. The insulation layer 130 is made of cross-linked polyethylene material, which can play a precise positioning role when extruding the inner buffer layer 140, preventing the inner buffer layer 140 from shifting during wrapping or extrusion, ensuring the compatibility between the inner buffer layer 140 and the insulation layer 130, and improving the overall structural stability of the cable.

[0023] In some specific implementation schemes, the outer flame retardant layer 190 has a thickness of 2-4mm, which prevents external flames from penetrating to the inner structure. Its low smoke and halogen-free properties also reduce the release of toxic fumes during combustion, improving safety and environmental friendliness. The outer surface of the outer flame retardant layer 190 is uniformly distributed with diamond-shaped anti-slip textures. The outer flame retardant layer 190 is a low smoke and halogen-free flame retardant polyolefin material, which can increase the friction during laying, making it easier for construction workers to grip and drag, preventing the cable from slipping during laying, and improving the ease of construction.

[0024] In some specific implementations, the outer buffer layer 180 is a low-smoke halogen-free elastic tape. The cross-section of the outer buffer layer 180 is corrugated, with the peak height of the corrugation being 0.8-1.2 mm and the trough depth being the same as the peak height. When wrapping, the overlapping part accounts for 25-35% of the width of a single turn of tape. This ensures that the outer buffer layer 180 completely covers the outer circumference of the armor layer 170, avoids the exposure of the spiral winding gap of the armor layer 170, prevents the sharp edges of the armor layer 170 from damaging the inner structure, and enhances the overall compression and vibration resistance of the cable.

[0025] In some specific implementations, the buffer filling core 112 is a cylindrical elastomer with a diameter of 1.5-2.0 mm. Multiple hemispherical elastic protrusions are evenly distributed on the surface of the buffer filling core 112, with a protrusion diameter of 0.3-0.4 mm and a distance of 0.5-0.8 mm between two adjacent protrusions.

[0026] In some specific implementation schemes, the flame-retardant filler strip 111 is made of flame-retardant glass fiber rope, which has good flame-retardant properties and can block the spread of flames in the twisted gap of conductor 110. The major axis of its elliptical cross-section is consistent with the width of the twisted gap of conductor 110, which can tightly fill the gap and avoid leaving gaps. The arc-shaped fitting surfaces on both sides of the rope body that are adapted to the buffer filling core 112 can make the flame-retardant filler strip 111 and the buffer filling core 112 fit seamlessly, forming a stable internal filling structure, which not only helps to fix conductor 110, but also improves the flame retardancy and compression resistance of conductor 110.

[0027] Working principle: The core conductor 110 (multi-strand aluminum alloy stranded) is responsible for power transmission. Flame-retardant filler strips 111 (flame-retardant fiberglass rope) within the stranding gaps provide initial fire resistance, while the buffer filler core 112 (with raised elastomers) absorbs stress and prevents misalignment. The inner shielding layer 120 (semi-conductive cross-linked polyethylene, with a corrugated inner surface) ensures a uniform electric field and reduces interference. The insulation layer 130 (cross-linked polyethylene) provides electrical insulation, and the raised ridges on the outer surface ensure interlayer adhesion. The inner buffer layer 140 (elastic rubber, with...) Flame-retardant granular buffer holes absorb compression and protect the insulation layer 130; the outer shielding layer 150 and the inner shielding layer 120 form a double shield to enhance anti-interference; the inner flame-retardant layer 160 constructs the first flame-retardant defense line, and the armor layer 170 improves mechanical strength; the outer buffer layer 180 (corrugated low-smoke halogen-free elastic strip) provides secondary buffering, and the outer flame-retardant layer 190 (low-smoke halogen-free flame-retardant polyolefin) and the inner flame-retardant layer 160 work together to prevent fire and penetration. Its anti-slip texture facilitates laying, ultimately achieving stable transmission and protection under medium pressure.

[0028] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A medium-voltage flame-retardant aluminum alloy power cable, characterized in that, The device includes a conductor formed by stranding multiple aluminum alloy wire cores. Multiple flame-retardant filler strips and buffer filler cores are filled in the gaps between the strands of the aluminum alloy wire cores. The flame-retardant filler strips and buffer filler cores are arranged alternately. An inner shielding layer tightly wraps around the outer periphery of the conductor. An insulation layer is extruded onto the outer periphery of the inner shielding layer. An inner buffer layer is extruded onto the outer periphery of the insulation layer. An outer shielding layer tightly wraps around the outer periphery of the inner buffer layer. An inner flame-retardant layer is wrapped around the outer periphery of the outer shielding layer. An armor layer is spirally wound around the outer periphery of the inner flame-retardant layer. An outer buffer layer is wrapped around the outer periphery of the armor layer. An outer flame-retardant layer is extruded onto the outer periphery of the outer buffer layer.

2. The medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The inner buffer layer is provided with a plurality of buffer holes, each of which has a diameter of 0.5-1.0 mm. The inner surface of the inner buffer layer is provided with arc-shaped protrusions, which are attached and fixed to the insulating layer.

3. The medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The inner surface of the inner shielding layer is wavy, and the overall thickness of the inner shielding layer is 0.8-1.2 mm.

4. The medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The thickness of the insulating layer is 3-5mm, and four axial positioning protrusions are evenly distributed along the circumferential direction on the outer surface of the insulating layer.

5. A medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The thickness of the outer flame-retardant layer is 2-4mm, and the outer surface of the outer flame-retardant layer is uniformly distributed with diamond-shaped anti-slip textures.

6. The medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The outer buffer layer is a low-smoke, halogen-free elastic band, and the cross-section of the outer buffer layer is corrugated.

7. A medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The buffer filling core is a cylindrical elastomer with a diameter of 1.5-2.0 mm, and multiple hemispherical elastic protrusions are evenly distributed on the surface of the buffer filling core.

8. A medium-voltage flame-retardant aluminum alloy power cable according to claim 1, characterized in that, The flame-retardant filler strip is a flame-retardant glass fiber rope with an elliptical cross-section, and its major axis length is consistent with the width of the conductor stranding gap.

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