Water-tree-resistant flame-retardant fireproof medium-voltage cable

Abstract

The utility model discloses a water-tree-resistant flame-retardant fire-resistant medium-voltage cable, which relates to the field of cables, aims to solve the problems that the service life of a medium-voltage cable in the prior art is affected and potential safety hazards exist due to the action of a use environment and an electric field, and adopts the technical scheme that the water-tree-resistant flame-retardant fire-resistant medium-voltage cable comprises a cable core, a filling layer, a flame-retardant fire-resistant structure and an outer sheath, a filling layer is arranged between the cable core and the flame-retardant fireproof structure, and an outer sheath is arranged outside the flame-retardant fireproof structure; the cable core comprises a conductive wire core, an insulating layer, a copper strip wrapping layer and a waterproof composite layer, the insulating layer, the copper strip wrapping layer and the waterproof composite layer are sequentially arranged on the conductive wire core, the flame-retardant fire-resistant structure comprises a fire-resistant layer, an isolating layer and a galvanized steel strip armor, the armor layer plays a role in isolating various external impacts and collisions in a fire, then the isolating layer plays a role in protecting the fire-resistant layer, and the waterproof composite layer is arranged on the waterproof composite layer. The fireproof layer plays a role in protecting the insulated wire cores, and in the structural combination, each combination is used for protecting the subsequent structure and plays a role in gradually progressive protection.

Description

Technical Field

[0001] This utility model relates to the field of cable technology, specifically to a water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable. Background Technology

[0002] During the laying and operation of medium-voltage cables, when mechanical stress or external forces cause damage to the cable sheath and insulation, or damage to the joints, moisture or water can seep in along the longitudinal and radial gaps of the cable. This rapidly increases the probability of water trees forming in the medium-voltage cable insulation under operating voltage. Once water trees grow to a certain length, they will cause permanent electrical tree defects at the tips, leading to cable insulation breakdown in a short period of time and causing power outages.

[0003] Therefore, the water tree resistance and fire resistance of medium-voltage cables are of great significance for ensuring the safety margin, reliability and lifespan of medium-voltage cables, and represent the future development direction of medium-voltage cables with broad development prospects. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the existing defects and provide a water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable, which can effectively solve the problems in the background art.

[0005] To achieve the above objectives, this utility model discloses a water tree resistant, flame retardant, and fire-resistant medium-voltage cable. The technical solution adopted includes a cable core, a filling layer, a flame retardant and fire-resistant structure, and an outer sheath. The filling layer is provided between the cable core and the flame retardant and fire-resistant structure, and the outer sheath is provided outside the flame retardant and fire-resistant structure.

[0006] The cable core includes a conductive core, an insulation layer, a copper strip wrapping layer, and a waterproof composite layer. The conductive core is provided with the insulation layer, the copper strip wrapping layer, and the waterproof composite layer in sequence. A conductor shielding layer is also provided between the conductive core and the insulation layer, and an insulating shielding layer is also provided between the insulation layer and the copper strip wrapping layer.

[0007] The flame-retardant and fire-resistant structure includes a fire-resistant layer, an isolation layer, and galvanized steel strip armor. By using a fire-resistant layer, an isolation layer, and an armor layer as the flame-retardant and fire-resistant structure, the armor layer isolates various external impacts and collisions during a fire, the isolation layer protects the fire-resistant layer, and the fire-resistant layer protects the insulated wire core. In this structural combination, each combination is designed to protect the subsequent structure, providing a progressively progressive protection.

[0008] As a preferred embodiment of this invention, the conductive core is made of annealed copper wire stranded together.

[0009] As a preferred embodiment of this invention, the insulating layer is made of polypropylene, a water-tree resistant medium-voltage insulating material.

[0010] As a preferred technical solution of this utility model, the waterproof composite layer consists of 2-3 layers of longitudinally wrapped aluminum-plastic composite tape and an extruded polyethylene inner sheath. By using the waterproof composite layer, the cable's resistance to water treeing can be improved, its service life extended, and the safety of the power system enhanced. The 2-3 layers of longitudinally wrapped aluminum-plastic composite tape have a more compact structure than the wrapped aluminum-plastic composite tape, which can reduce the ingress of moisture. The copper tape wrapping layer is located inside the aluminum-plastic composite tape in the waterproof composite layer. Only by adopting this structure can the insulating shielding layer and the copper tape wrapping layer be combined together to form a shielding structure.

[0011] As a preferred technical solution of this utility model, the filling layer includes water-blocking particles and flame-retardant filler. The flame-retardant filler is made of rock wool rope or flame-retardant PP rope. Water-blocking particles are filled inside the flame-retardant filler. The water-blocking particles can absorb moisture that penetrates into the cable from the outside, preventing moisture from corroding the inside of the cable. Combined with aluminum-plastic composite tape, polyethylene inner sheath, and polypropylene insulation, the moisture resistance of the cable is improved, the internal corrosion of the cable by moisture is reduced, and the formation of water trees is avoided.

[0012] As a preferred embodiment of this utility model, the refractory layer is a fiberglass tape or a ceramicized silicone rubber tape, and the number of wrapping layers is 3-4.

[0013] As a preferred technical solution of this utility model, the isolation layer is a mineral fireproof material ceramicized polymer, and the polymer is made of silicone rubber or polyolefin.

[0014] As a preferred technical solution of this utility model, the outer sheath is made of low-smoke halogen-free polyolefin.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model can improve the water tree resistance of the cable by adopting a waterproof composite layer, extend the service life of the cable, and improve the safety of the power system. The longitudinal wrapping of 2-3 layers of aluminum-plastic composite tape is more airtight than the wrapping of aluminum-plastic composite tape, which can reduce the ingress of moisture. The copper tape wrapping layer is set inside the aluminum-plastic composite tape in the waterproof composite layer. Only by adopting this structure can the insulating shielding layer and the copper tape wrapping layer be combined together to form a shielding structure.

[0016] In this invention, water-blocking particles and flame-retardant filler are used as the filling layer. Water-blocking particles are filled inside the flame-retardant filler. The water-blocking particles can absorb moisture that penetrates into the cable from the outside, preventing moisture from corroding the inside of the cable. Combined with aluminum-plastic composite tape, polyethylene inner sheath, and polypropylene insulation, the moisture resistance of the cable is improved, the internal corrosion of the cable by moisture is reduced, and the formation of water trees is avoided.

[0017] In this utility model, a fire-resistant layer, an isolation layer, and an armor layer are used as the flame-retardant and fire-resistant structure. The armor layer isolates various external impacts and collisions during a fire, the isolation layer protects the fire-resistant layer, and the fire-resistant layer protects the insulated wire core. In this structural combination, each combination is for the purpose of protecting the following structure, playing a progressively progressive role in protection. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the cable core structure of this utility model.

[0020] In the diagram: 1. Conductive core; 2. Conductor shielding layer; 3. Insulation layer; 4. Insulation shielding layer; 5. Copper strip wrapping layer; 6. Waterproof composite layer; 7. Filler layer; 8. Fire-resistant layer; 9. Isolation layer; 10. Galvanized steel strip armor; 11. Outer sheath. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example 1

[0022] like Figures 1 to 2 As shown, this utility model discloses a water tree resistant, flame retardant and fire resistant medium-voltage cable. The technical solution adopted is as follows: it includes a cable core, a filling layer 7, a flame retardant and fire resistant structure and an outer sheath 11. The filling layer 7 is provided between the cable core and the flame retardant and fire resistant structure. The filling layer 7 includes water-blocking particles and flame retardant filler. The flame retardant filler is made of rock wool rope.

[0023] The flame-retardant and fire-resistant structure is provided with an outer sheath 11; the outer sheath 11 is made of low-smoke halogen-free polyolefin.

[0024] The cable core includes a conductive core 1, an insulation layer 3, a copper tape wrapping layer 5, and a waterproof composite layer 6. The conductive core 1 is made of annealed copper wire stranded together. The insulation layer 3, the copper tape wrapping layer 5, and the waterproof composite layer 6 are sequentially arranged on the conductive core 1. The waterproof composite layer 6 consists of a three-layer longitudinally wrapped aluminum-plastic composite tape and an extruded polyethylene inner sheath. This double-layer waterproof structure improves the cable's resistance to water treeing.

[0025] A conductor shielding layer 2 is provided between the conductive core 1 and the insulation layer 3, and an insulating shielding layer 4 is provided between the insulation layer 3 and the copper strip wrapping layer 5. The insulation layer 3 is made of water-tree resistant medium-voltage insulating polypropylene. The insulating shielding layer 4 is made of polypropylene and carbon black, with carbon black accounting for 20% by weight.

[0026] The flame-retardant and fire-resistant structure includes a fire-resistant layer 8, an isolation layer 9, and a galvanized steel strip armor 10.

[0027] The refractory layer 8 is a ceramicized silicone rubber tape with four wrapping layers.

[0028] The isolation layer 9 is a ceramicized polymer of mineral fire-retardant material, and the polymer is a polyolefin.

[0029] The circuits and mechanical connections involved in this utility model are common practices used by those skilled in the art, and technical inspiration can be obtained through a limited number of experiments. They are common knowledge.

[0030] Components not described in detail in this article are existing technologies.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable, characterized in that: It includes a cable core, a filling layer (7), a flame-retardant and fire-resistant structure and an outer sheath (11). The filling layer (7) is provided between the cable core and the flame-retardant and fire-resistant structure, and the outer sheath (11) is provided outside the flame-retardant and fire-resistant structure. The cable core includes a conductive core (1), an insulation layer (3), a copper strip wrapping layer (5), and a waterproof composite layer (6). The conductive core (1) is provided with the insulation layer (3), the copper strip wrapping layer (5), and the waterproof composite layer (6) in sequence. A conductor shielding layer (2) is also provided between the conductive core (1) and the insulation layer (3). An insulating shielding layer (4) is also provided between the insulation layer (3) and the copper strip wrapping layer (5). The flame-retardant and fire-resistant structure includes a fire-resistant layer (8), an isolation layer (9), and galvanized steel strip armor (10). The waterproof composite layer (6) consists of a 2-3 layer aluminum-plastic composite strip and an extruded polyethylene inner protective layer.

2. The water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable according to claim 1, characterized in that: The conductive core (1) is made of annealed copper wire stranded together.

3. The water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable according to claim 1, characterized in that: The insulation layer (3) is made of polypropylene, a water-tree resistant medium-voltage insulating material.

4. The water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable according to claim 1, characterized in that: The filling layer (7) includes water-blocking particles and flame-retardant filler, wherein the flame-retardant filler is made of rock wool rope or flame-retardant PP rope.

5. The water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable according to claim 1, characterized in that: The refractory layer (8) is a fiberglass tape or a ceramicized silicone rubber tape, with 3-4 layers.

6. The water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable according to claim 1, characterized in that: The isolation layer (9) is a mineral fireproof material ceramicized polymer, and the polymer is made of silicone rubber or polyolefin.

7. The water-tree resistant, flame-retardant, and fire-resistant medium-voltage cable according to claim 1, characterized in that: The outer sheath (11) is made of low-smoke halogen-free polyolefin.

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