CN206441575U - Times capacity midium voltage cable - Google Patents

Abstract

The utility model relates to a double-capacity medium-voltage cable. The medium-voltage cable includes an inner support interlock tube (1) and a conductive insulating core wrapped around the inner support interlock tube (1), an inner protective layer (10), armor layer (11) and outer sheath (12); the inner supporting interlocking tube (1) is an aluminum or steel interlocking sleeve; the conductive insulated wire core sequentially includes wires, wires A shielding layer (4) and an insulating layer (5). The double-capacity medium-voltage cable of the utility model can increase the carrying capacity by 20%-30% under the same level of conditions; can save 10%-20% of conductors under the same cross-section; and has flame-retardant and environmental protection properties.

Description

Double capacity medium voltage cable

technical field

The utility model belongs to the field of cables, in particular to a medium-voltage cable with double capacity, which is suitable for power transmission in large, medium and short distances and other important public places.

Background technique

Medium-voltage cables, with a rated voltage of 6-35KV, are mainly used for power system transmission and distribution of electric energy fixed laying lines, used in densely populated electrified subways, stations, ports, sports center squares, high-rise buildings, computer information centers, modern Large shopping malls and other important social public places. It has a series of advantages, such as: excellent electrical properties and mechanical and physical properties; excellent low-smoke and halogen-free Class A flame retardancy; low smoke generation, small halogen acid gas release, fire spread and harmful gases to people and Biological poisoning.

Conventional medium-voltage cables, especially medium-voltage cables with large cross-sections, according to the skin effect theory, the current in the conductor tends to flow toward the surface, and the closer to the center, the smaller the current. Reasonable utilization results in a waste of copper. The double-capacity medium-voltage cable designed in this paper is based on this theory and is designed in practice. There are research institutions abroad who are also developing this type of product, but most of them are from Functional considerations, such as realizing heating, improving shielding effect, etc., but not considering how to increase the current carrying capacity of the product and save copper materials.

Utility model content

Aiming at the defects in the prior art, the utility model provides a medium-voltage cable with double capacity. Under the condition of the same level, the carrying capacity of the cable is enhanced and the consumption of conductors is reduced.

In order to achieve the above purpose, the technical solution adopted by the utility model is to provide a double-capacity medium-voltage cable, including an inner supporting interlocking tube and a conductive insulating core wrapped around the inner supporting interlocking tube in turn, an inner sheath, The armor layer and the outer sheath; the inner support interlocking tube is an aluminum or steel interlocking sleeve.

Further, as for the double-capacity medium-voltage cable described above, the conductive insulated core includes a wire, a wire shielding layer, an insulating layer, an insulating shielding layer, and a metal shielding layer sequentially from the inside to the outside.

Furthermore, as for the double-capacity medium-voltage cable described above, the conductors have a double-layer structure, including S-shaped or Z-shaped inner conductors and trapezoidal outer conductors.

Further, as for the double-capacity medium-voltage cable described above, both the wire shielding layer and the insulating shielding layer are semi-conductive shielding layers.

Furthermore, as for the double-capacity medium-voltage cable described above, the insulating layer is a cross-linked polyethylene insulating layer.

Further, as for the double-capacity medium-voltage cable described above, the outer periphery of the conductive and insulated core is wrapped around the cladding by a glass fiber tape.

Furthermore, as for the double-capacity medium-voltage cable described above, the gap formed between the wrapping layer and the conductive insulating core is filled with the glass fiber rope filling layer.

Further, as for the double-capacity medium-voltage cable described above, the inner sheath is a low-smoke halogen-free polyolefin inner sheath.

Furthermore, as for the double-capacity medium-voltage cable described above, the armor layer is a galvanized steel tape armor layer.

Further, as for the double-capacity medium-voltage cable described above, the outer sheath is a low-smoke, halogen-free polyolefin flame-retardant outer sheath.

The beneficial technical effects of the utility model are:

(1) The utility model sets the internal support interlocking tube in the conductive insulating wire core, so that under the same specification and the same effect, the current carrying capacity of the cable is increased by 20%-30%, and the conductor usage is saved by 10%-20% %;

(2) The wire adopts a double-layer structure, the inner layer is S-shaped or Z-shaped, and the outer layer is trapezoidal. On the one hand, it reduces the extrusion of the inner support interlocking tube during processing, and on the other hand, it increases its compression coefficient, so that Its combination is tighter and the utilization rate of the conductor is improved;

(3) The filling layer and wrapping layer adopt glass fiber material layer to make it have flame retardant properties;

(4) The outer sheath adopts polyolefin flame-retardant sheath layer. In addition to its flame-retardant properties, because it does not contain halogen elements, it will not produce suffocating smoke in the event of a fire, and will not cause secondary damage.

Description of drawings

Fig. 1 is a structural schematic diagram of a double-capacity medium-voltage cable of the present invention.

In the picture:

1-Inner support interlock tube 2-Inner wire 3-Outer wire 4-Wire shield

5-Insulation layer 6-Insulation shielding layer 7-Metal shielding layer 8-Filling layer 9-Wrapping layer

10-inner sheath 11-armour 12-outer sheath

detailed description

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described in further detail.

As shown in Figure 1, it is a double-capacity medium-voltage cable provided by the utility model, which includes an inner support interlock tube 1 and a conductive insulating core, an inner sheath 10, and an armored cable that are arranged in turn on the periphery of the inner support interlock tube 1 layer 11 and outer sheath 12.

The inner supporting interlocking tube 1 is made of aluminum or steel interlocking sleeve, thereby changing the structure of the conductive insulating wire core being solid, saving the amount of conductor used, and increasing the ampacity of the cable. The size of its inner cavity and outer diameter is calculated by the skin effect theory. The inner support interlocking tube 1 can be pre-coated with monitoring lines such as temperature-sensing optical fibers and measurement signal lines, so as to better realize the intelligence of the power grid. The inner supporting interlocking pipe 1 can be manufactured by an interlocking armoring machine.

The conductive insulated wire core 1 includes a wire, a wire shielding layer 4 , an insulating layer 5 , an insulating shielding layer 6 and a metal shielding layer 7 sequentially from inside to outside.

The wire has a double-layer structure, including an S-shaped or Z-shaped inner layer wire 2 and a ladder-shaped outer layer wire 3 . On the one hand, it reduces the extrusion of the inner support interlocking tube during processing, on the other hand, it increases its compression coefficient to make it more tightly combined and improve the utilization rate of the conductor.

The wire shielding layer 4 is a semi-conductive shielding layer, which evenly covers the conductor surface and plays the role of homogenizing the electric field; the insulating layer 5 is a cross-linked polyethylene insulating layer, which has good heat resistance, strong load capacity, non-melting, and chemical resistance. Corrosion, high mechanical strength; the insulating shielding layer 6 is a semi-conductive shielding layer, which has good contact with the shielded insulating layer, thereby avoiding gap discharge between the insulating layer and the shielding layer; the metal shielding layer 7 is a copper tape shielding layer , using electrician copper tape shielding layer.

The cable of the utility model adopts three insulated wire cores to be twisted into a cable, and the periphery of the three insulated wire cores is fastened by the wrapping layer 9 , and the gap formed between the wrapping layer 9 and the conductive insulating wire core is filled by the filling layer 8 . The filling layer 8 adopts a glass fiber rope filling layer, and the wrapping layer 9 is a glass fiber tape wrapping layer. Because glass fiber has the advantages of good insulation, strong heat resistance, good corrosion resistance and high mechanical strength.

The inner sheath 10 adopts a low-smoke halogen-free polyolefin inner sheath, which has flame retardancy, so that the cable can better play a flame-retardant effect under the condition of an external flame.

The armor layer 11 is a hot-dip galvanized steel tape armor layer, which makes the external impact resistance of the cable more superior.

The outer sheath 12 is a low-smoke halogen-free polyolefin flame-retardant sheath layer. In addition to having flame-retardant properties, because it does not contain halogen elements, it will not produce suffocating smoke in the event of a fire, and will not cause secondary damage .

To sum up, the double capacity medium voltage cable provided by the utility model realizes that under the same specification and the same effect, the current carrying capacity of the cable is increased by 20%-30%, and the conductor usage is saved by 10%-20%, thereby saving costs. At the same time, combined with the emergence of the smart grid, the temperature-sensing optical fiber, the measurement signal line and other monitoring lines are pre-applied in the inner support interlocking tube, which better realizes the intelligence of the grid.

The double-capacity medium-voltage cable of the present invention is not limited to the above-mentioned specific embodiments. Those skilled in the art can obtain other embodiments according to the technical solution of the present invention, which also belong to the technical innovation scope of the present invention.

Claims (10)

1. A double-capacity medium-voltage cable, characterized in that it includes an inner support interlock tube (1) and a conductive insulating core wrapped around the inner support interlock tube (1) in turn, an inner sheath (10), The armor layer (11) and the outer sheath (12); the inner support interlocking pipe (1) is an aluminum or steel interlocking sleeve. 2. The double-capacity medium-voltage cable according to claim 1, characterized in that: the conductive insulated wire core sequentially includes a wire, a wire shielding layer (4), an insulating layer (5), an insulating shielding layer ( 6) and metal shielding layer (7). 3. The double-capacity medium-voltage cable according to claim 2, characterized in that: said conductors have a double-layer structure, including S-shaped or Z-shaped inner conductors (2) and trapezoidal outer conductors (3). 4. The double-capacity medium-voltage cable according to claim 3, characterized in that: both the wire shielding layer (4) and the insulating shielding layer (6) are semi-conductive shielding layers. 5. The double-capacity medium-voltage cable according to claim 4, characterized in that: the insulating layer (5) is a cross-linked polyethylene insulating layer. 6. The double-capacity medium-voltage cable according to claim 5, characterized in that: the outer periphery of the conductive insulating core is wrapped around the cladding (9) by glass fiber tape. 7. The double-capacity medium-voltage cable according to claim 6, characterized in that: the gap formed between the wrapping layer (9) and the conductive insulating core is filled by the glass fiber rope filling layer (8). 8. The double-capacity medium-voltage cable according to claim 7, characterized in that: the inner sheath (10) is a low-smoke halogen-free polyolefin inner sheath. 9. The double capacity medium voltage cable according to claim 8, characterized in that: the armor layer is a galvanized steel tape armor layer. 10. The double-capacity medium-voltage cable according to claim 9, characterized in that: the outer sheath is a low-smoke, halogen-free polyolefin flame-retardant outer sheath.