Power cable with long service life

Abstract

The utility model relates to a long-life power cable, which comprises wire cores and a protective sheath, a plurality of wire cores are arranged in the protective sheath, each wire core comprises a conductor, a filling rope and an insulating layer, the insulating layer is coated outside the conductor, the filling rope is filled between the conductor and the insulating layer, the filling rope has flame retardance, and the insulating layer is of a double-layer co-extrusion structure. Compared with the prior art, the insulating layer of the long-life power cable provided by the utility model adopts a double-layer co-extrusion structure, and compared with a single-layer insulating structure of an existing cable, the insulating performance is more stable, the cable insulating resistance is guaranteed for a long time, and the cable can operate stably for a long time, so that the service life reaches 70 years and is matched with the service life of a building; and the cable does not need to be replaced throughout the life.

Description

Technical Field

[0001] The utility model relates to the technical field of wire and cable, in particular to a high-life power cable. Background Art

[0002] The service life of ordinary cables is generally 30 years, while the design life of current residential communities, commercial buildings, public places and other buildings is generally 70 years. This results in that these buildings need to replace the cables for the fire protection system, emergency system, lighting system, power transmission and distribution system, etc. at least once during their whole life cycle, increasing the later maintenance cost of these buildings. Content of the Utility Model

[0003] In view of this, it is necessary to provide a high-life power cable to solve the technical problem that the life of the high-life power cable in the prior art is short and does not match the service life of buildings.

[0004] The utility model provides a high-life power cable, which includes: a core and a protective sheath. A plurality of cores are disposed in the protective sheath. Each core includes a conductor, a filling rope and an insulating layer. The insulating layer is coated outside the conductor, and the filling rope is filled between the conductor and the insulating layer. The filling rope has flame retardancy, and the insulating layer is a double-extrusion structure.

[0005] Further, the core further includes a fire-resistant layer coated outside the conductor, and the insulating layer is coated outside the fire-resistant layer.

[0006] Further, the insulating layer is an irradiated cross-linked polyolefin insulating layer.

[0007] Further, the filling ropes are twisted with a plurality of cores to form a cable core, and the protective sheath is coated outside the cable core.

[0008] Further, the filling rope is any one of a flame-retardant high-temperature filling rope, a glass fiber filling rope, and a flame-retardant PP filling rope.

[0009] Further, the protective sheath includes an isolating layer coated outside the cable core.

[0010] Further, the protective sheath further includes an inner lining layer coated outside the isolating layer.

[0011] Further, the protective sheath further includes an armor layer coated outside the inner lining layer.

[0012] Further, the armor layer is a metal wire armor or a metal tape armor.

[0013] Further, the protective sheath further includes an outer sheath coated outside the armor layer.

[0014] Compared with the prior art, the insulating layer of the high - life power cable provided by the present utility model adopts a double - layer co - extrusion structure. Compared with the single - layer insulation structure of existing cables, the insulation performance is more stable, the insulation resistance of the cable is guaranteed for a long time, the cable can operate stably for a long time, so that the service life reaches 70 years, which matches the service life of buildings and achieves the effect of not needing to replace the cable throughout the life.

[0015] The above description is only an overview of the technical solution of the present utility model. In order to understand the technical means of the present utility model more clearly and be able to implement it according to the content of the description, the preferred embodiments of the present utility model are described in detail below in conjunction with the accompanying drawings. The specific implementation manners of the present utility model are given in detail by the following embodiments and their accompanying drawings. Brief Description of the Drawings

[0016] The drawings described herein are used to provide a further understanding of the present utility model and form a part of this application. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation of the present utility model. In the drawings:

[0017] Figure 1 It is a cross - sectional view of a preferred embodiment of the high - life power cable provided by the present utility model. Detailed Description of the Preferred Embodiments

[0018] The preferred embodiments of the present utility model will be specifically described below in conjunction with the accompanying drawings. The accompanying drawings form a part of this application and are used together with the embodiments of the present utility model to explain the principle of the present utility model, rather than to limit the scope of the present utility model.

[0019] Please refer to Figure 1 , the present utility model provides a high - life power cable. The high - life power cable includes a core 1 and a protective sheath 2. A plurality of cores 1 are placed in the protective sheath 2, and the protective sheath 2 plays a role in protecting the cores 1. The core 1 includes a conductor 11 and an insulating layer 12 coated outside the conductor 11. The conductor 11 is used for conducting electricity, and the insulating layer 12 is used to prevent the conductor 11 from leaking electricity. A filling rope 3 is filled between the conductor 11 and the insulating layer 12, and the filling rope 3 has flame - retardant properties. The insulating layer 12 is of a double - layer co - extrusion structure. Compared with the single - layer insulation structure of existing cables, the insulation performance is more stable, the insulation resistance of the cable is guaranteed for a long time, the cable can operate stably for a long time, so that the service life reaches 70 years, which matches the service life of buildings and achieves the effect of not needing to replace the cable throughout the life.

[0020] In some embodiments, the conductor 11 is a plated or unplated annealed copper conductor or aluminum or aluminum alloy in GB / T 3956 - 2008, and the structure is the first, second, or fifth type of conductor in GB / T 3956 - 2008.

[0021] In some embodiments, the insulating layer 12 is extruded by double-layer co-extrusion, and the two layers should be completely bonded. The insulating material is an irradiated cross-linked polyolefin material, that is, an irradiated cross-linked polyolefin insulating layer. The temperature resistance grades are 90°C, 105°C, and 125°C, which are determined by the long-term operating temperature of the conductor. It is preferably 125°C.

[0022] In some embodiments, the core 1 further includes a fire-resistant layer 13, and the fire-resistant layer 13 is located between the conductor 11 and the insulating layer 12. That is, the fire-resistant layer 13 is wrapped around the conductor 11, and the insulating layer 12 is wrapped around the fire-resistant layer 13. The fire-resistant layer 13 is formed by winding or longitudinally wrapping a fire-resistant mica tape, and the fire-resistant mica tape is the mica tape with powder for fire-resistant safety cables specified in JB / T 64885.5, with a nominal thickness of 0.08 - 0.18 mm.

[0023] In some embodiments, the number of cores 1 can be 1 core, 2 cores, 3 cores, 4 cores (3 + 1 core), 5 cores (3 + 2 cores, 4 + 1 core), etc. In this embodiment, 3 cores are taken as an example for illustration.

[0024] In some embodiments, the filling cord 3 is stranded with a plurality of cores 1 to form a cable core, and the protective sheath 2 is wrapped around the cable core.

[0025] The filling cord 3 is any one of a flame-retardant high-temperature filling cord, a glass fiber filling cord, and a flame-retardant PP filling cord. The filling requirement is tight and round, and it does not stick to the core 1. The selection of the filling cord 3 is determined according to the flame-retardant grade of the cable.

[0026] In some embodiments, the protective sheath 2 includes an isolating layer 21, and the isolating layer 21 is wrapped around the cable core. The isolating layer 21 is formed by overlapping and winding a non-hygroscopic material thin film tape, and the overlapping rate of winding is 15% - 25%. It can be made of non-woven fabric, high flame-retardant tape, CPP tape, etc.

[0027] In some embodiments, the protective sheath 2 further includes an inner lining layer 22, and the inner lining layer 22 is wrapped around the isolating layer 21. The inner lining layer 22 is extruded with a halogen-free low-smoke flame-retardant irradiated cross-linked polyolefin. The material of the inner lining layer 22 should adapt to the operating temperature of the cable and be compatible with the cable insulating material, and its nominal thickness is 1.0 - 2.0 mm.

[0028] In some embodiments, the protective sheath 2 further includes an armor layer 23, and the armor layer 23 is wrapped around the inner lining layer 22. The armor layer 23 is made of metal wire armor or metal tape armor. The metal wire should be galvanized steel wire, and the metal tape should be galvanized steel tape or aluminum alloy interlocking armor. The single-core cable armor for an AC circuit should use non-magnetic materials. The nominal diameter of the galvanized steel wire is 0.8 - 3.15 mm, the nominal thickness of the galvanized steel tape is 0.5 - 0.8 mm, and the nominal thickness of the aluminum alloy interlocking armor tape is 0.5 mm and 0.6 mm.

[0029] In some embodiments, the protective skin 2 further includes an outer sheath 24, which is coated outside the armor layer 23. The outer sheath 23 is extruded from halogen-free, low-smoke, flame-retardant, radiation-cross-linked polyolefin. The temperature grade of the outer sheath 24 and the insulation material should match. The nominal thickness of the single-core cable is greater than or equal to 1.4 mm, and the nominal thickness of the multi-core cable is greater than or equal to 1.8 mm.

[0030] Compared with the prior art, the insulation layer of the long-life power cable provided by the utility model adopts a double-layer co-extrusion structure, while ordinary long-life power cables are single-layer structures. The insulating material used in the present application is adapted to the long-term operating temperature of the conductor 11, and can reach 125°C during normal operation, while ordinary long-life power cables can only withstand 90°C during normal operation. The insulation layer 12 material, the inner lining layer 22 material and the outer sheath 24 material of the present application are irradiated cross-linked polyolefin materials. The cross-linking method of the insulation layer 12, the inner lining layer 22 and the outer sheath 24 of the present application is electron beam irradiation, while ordinary long-life power cables only need to be cross-linked for insulation, generally steam cross-linking. Through the above structural and material changes, the performance of the present application is more stable, the cable insulation resistance is guaranteed for a long time, and the cable can operate stably for a long time, so that the service life reaches 70 years, which exceeds the 30-year service life of ordinary cables. Matching the service life of the building, the effect of not having to replace the cable for a lifetime is achieved.

[0031] The above is only a preferred specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be included in the protection scope of the present invention.

Claims

1. A long-life power cable, characterized in that: It includes: A wire core and a protective sheath, wherein several of the wire cores are built into the protective sheath, the wire core comprises a conductor, a filling rope and an insulating layer, the insulating layer is coated on the outside of the conductor, the filling rope is filled between the conductor and the insulating layer, the filling rope is flame retardant, and the insulating layer is a double-layer co-extrusion structure; the filling rope and several of the wire cores are twisted to form a cable core, and the protective sheath is coated on the outside of the cable core; the protective sheath comprises an isolation layer, and the isolation layer is coated on the outside of the cable core.

2. The long-life power cable according to claim 1, characterized in that: The wire core further comprises a fire-resistant layer, wherein the fire-resistant layer is coated on the outside of the conductor, and the insulating layer is coated on the outside of the fire-resistant layer.

3. The long-life power cable according to claim 1, characterized in that: The insulating layer is a radiation cross-linked polyolefin insulating layer.

4. The long-life power cable according to claim 1, characterized in that: The filling rope is any one of a flame retardant high temperature filling rope, a glass fiber filling rope, and a flame retardant PP filling rope.

5. The long-life power cable according to claim 1, characterized in that: The protective skin also includes an inner lining layer, and the inner lining layer is coated outside the isolation layer.

6. The long-life power cable according to claim 5, characterized in that: The protective skin also includes an armor layer, and the armor layer is coated outside the inner lining layer.

7. The long-life power cable according to claim 6, characterized in that: The armor layer is metal wire armor or metal tape armor.

8. The long-life power cable according to claim 6, characterized in that: The protective skin also includes an outer sheath, which is coated outside the armor layer.

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