CN217214198U - Cross-linked polyethylene insulated B1-grade flame-retardant power cable for rail transit - Google Patents

Abstract

The utility model relates to a power cable technical field particularly relates to track traffic is with insulating B1 level fire-retardant power cable of crosslinked polyethylene, include: each conductive core comprises a stranded conductor, an insulating layer extruded outside the stranded conductor and a mica tape wrapped on the outer wall of the insulating layer; and the inorganic oxygen-isolating filling layer is filled in the outer walls of the conductive cores and is fixedly formed into a circular section by a wrapping tape, wherein a plurality of expansion ropes are arranged in the inorganic oxygen-isolating filling layer, and each expansion rope comprises a water-blocking rope and a foaming layer. The expansion rope is arranged in the inorganic oxygen-isolating filling layer and comprises a water-blocking rope and a foaming layer, the weight of the inorganic oxygen-isolating filling layer can be reduced through the arrangement of the expansion rope, the bending performance of the cable is improved, meanwhile, the waterproof capacity of the cable can be improved through the water absorption effect of the water-blocking rope, the water of the joint part is prevented from entering the conductor, the water content of the inorganic oxygen-isolating layer is increased, the flame retardance of the cable is improved, and the flame retardant effect of the cable is improved.

Description

Cross-linked polyethylene insulated B1-grade flame-retardant power cable for rail transit

Technical Field

The utility model relates to a power cable technical field particularly relates to track traffic is with insulating B1 level fire-retardant power cable of crosslinked polyethylene.

Background

The urban rail transit power supply system is a system for providing required electric energy for urban rail transit operation, not only provides traction power for an urban rail transit electric train, but also provides electric energy for other facilities of the urban rail transit operation service, such as lighting, ventilation, air conditioning, water supply and drainage, communication, signals, disaster prevention alarm, escalators and the like.

In order to meet the flame retardant standard of B1 grade, an inorganic oxygen-isolating filling layer is usually extruded in the cable to improve the flame retardant property, but the filling layer can increase the weight of the cable and also reduce the flexibility and mechanical fatigue property of the cable.

SUMMERY OF THE UTILITY MODEL

Defect and not enough to the fire-retardant power cable of cross-linked polyethylene insulation B1 level among the prior art for the track traffic, the utility model aims to reduce the weight of whole cable, improve the waterproof nature and the flexibility of cable.

The utility model provides a track traffic is with fire-retardant power cable of crosslinked polyethylene insulation B1 level, include:

a plurality of conductive cores;

the inorganic oxygen-isolating filling layer is filled in the outer walls of the conductive cores and is wrapped outside by a wrapping tape to form a circular cross section;

the shielding layer is coated on the outer wall of the wrapping tape;

the inner sheath is extruded on the outer wall of the shielding layer;

the glass ribbon is wrapped on the outer wall of the inner sheath;

the outer sheath is extruded on the outer wall of the glass ribbon;

each conductive core comprises a stranded conductor, an insulating layer extruded outside the stranded conductor and a mica tape wrapped on the outer wall of the insulating layer;

a plurality of expansion ropes are arranged in the inorganic oxygen-insulating filling layer, and each expansion rope comprises a water-blocking rope and a foaming layer;

preferably, the water blocking rope comprises a plurality of water blocking yarns, and the foaming layer is arranged to be compressed after the water blocking rope absorbs water and expands.

Preferably, the foaming layer comprises a PP foaming strip, and the water blocking rope and the PP foaming strip are twisted to form the expansion rope.

Preferably, the water blocking rope and the PP foaming strips are in a 1+6 regular twisted structure, wherein the water blocking rope is positioned between the six PP foaming strips.

Preferably, the wrapping tape comprises a non-woven tape and a fluorophlogopite tape, the fluorophlogopite tape is wrapped on the outer wall of the non-woven tape, and the covering rate of the wrapping tape is more than 40%.

Preferably, the shielding layer comprises a longitudinally-wrapped aluminum-plastic/copper-plastic composite tape.

Preferably, the inner and outer sheaths comprise a halogen-free low smoke flame retardant polyolefin layer.

Preferably, the wrapping thickness of the glass ribbon is 3-4 mm.

Compared with the prior art, the utility model has the advantages of:

the utility model discloses be provided with the inflation rope in inorganic oxygen separation filling layer, the inflation rope is through the rope that blocks water and foaming layer strand shaping, can reduce the weight that inorganic oxygen separation filling layer through being provided with of inflation rope, improves the bending property of cable, simultaneously, through the effect of absorbing water of the rope that blocks water, can improve the waterproof ability of cable, prevent in the moisture invasion conductor of joint portion to increase the moisture content on inorganic oxygen separation layer, increase its fire resistance, improve the flame retardant efficiency of cable.

Drawings

The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

fig. 1 is a schematic structural view of a cross-linked polyethylene insulated B1 grade flame-retardant power cable for rail transit shown in the utility model;

fig. 2 is a schematic cross-sectional structure diagram of a cross-linked polyethylene insulated B1 grade flame-retardant power cable for rail transit shown in the utility model;

fig. 3 is a schematic structural view of the expansion rope according to the present invention.

Detailed Description

For a better understanding of the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.

Combine as shown in fig. 1-2, the utility model provides an insulating B1 level flame retardant power cable of crosslinked polyethylene for track traffic, it is main including many conductive cores 1, inorganic oxygen filling layer 2 that separates, the inflation rope 3, around band 4, shielding layer and sheath structure, inorganic oxygen filling layer 2 that separates is filled by inorganic fire retardant powder and is formed, for example, current commercial aluminium hydroxide powder, glass ceramic powder and resin particles's mixture, because inorganic fire retardant powder forms closely knit filling layer around band 4 around the package after, its density is greater than other insulating layers and restrictive coatings, lead to the weight of cable great, and the rigidity increases, consequently, through the mode that is provided with inflation rope 3 at inorganic oxygen filling layer 2 reduces inorganic oxygen filling layer 2's density, reduce its weight and rigidity promptly.

In an alternative embodiment, the inorganic oxygen-insulating filling layer 2 is filled among a plurality of conductive cores 1, and each conductive core 1 comprises a stranded conductor 11, an insulating layer 12 extruded outside the stranded conductor 11, and a mica tape 13 wrapped on the outer wall of the insulating layer 12.

The stranded conductor 11 may be formed by stranding an oxygen-free copper conductor in a regular stranding manner of 1+ 6.

The insulating layer 12 is formed by extruding crosslinked polyethylene material, and then a mica tape 13 is wrapped on the outer wall of the crosslinked polyethylene layer to form the structure of the conductive core 1.

Further, when filling inorganic oxygen barrier filling layer 2, make many electrically conductive cores 1 and expansion rope 3 pass along the horizontal direction and fill in inorganic fire-retardant powder's container bottom to use around band 4 to wrap the finished cable in the punch-out hole department, the volume goes out circular cross sectional shape.

Optionally, the wrapping tape 4 comprises a non-woven tape and a fluorophlogopite tape, the non-woven tape is wrapped on the outer walls of the plurality of conductive cores 1 and the filled inorganic flame-retardant powder to play a role in positioning and fixing, and the fluorophlogopite tape is wrapped on the outer wall of the non-woven tape to increase flame retardance.

In a preferred embodiment, in order to ensure the forming reliability of the inorganic oxygen-insulating filling layer 2, the lapping rate of the lapping tape 4 is more than 40%.

In the figure, a plurality of expansion ropes 3 are provided in the inorganic oxygen barrier filling layer 2.

Furthermore, the expansion rope 3 is formed by twisting the water-blocking rope 31 and the foaming layer 32, the density of the inorganic oxygen-insulating filling layer 2 can be reduced by arranging the water-blocking rope 31 and the foaming layer 32, the weight of the cable is reduced, the bending performance of the inorganic oxygen-insulating filling layer 2 can be improved by the deformation capacity of the foaming layer 32, the water-blocking rope 31 can improve the water-blocking performance of the cable in the inorganic oxygen-insulating filling layer 2, and the flame retardance of the inorganic oxygen-insulating filling layer 2 is improved by releasing water vapor into the inorganic oxygen-insulating filling layer 2 by heating when the cable is burnt.

Optionally, the water-blocking cord 31 includes a plurality of water-blocking yarns, and the foam layer 32 is configured to be compressed after the water-blocking cord 31 absorbs water and expands. Preferably, the foam layer 32 includes a PP foam strip, and the water blocking cord 31 and the PP foam strip are twisted to form the expansion cord 3.

In this way, the water-blocking cord 31 can sufficiently contact the moisture in the inorganic oxygen barrier filler layer 2, and prevent the moisture from penetrating in the direction of the conductor.

Preferably, the water blocking rope 31 and the PP foaming strips are in a regular twisted structure of 1+6, wherein the water blocking rope 31 is located between six PP foaming strips.

Furthermore, the shielding layer 5 is coated on the outer wall of the wrapping tape 4, and the shielding layer 5 can be selected from a longitudinally-wrapped aluminum-plastic/copper-plastic composite tape, so that the shielding tape has excellent shielding property and good flame retardance and water resistance.

Preferably, inner sheath 6 and oversheath 8 separate the oxygen layer for steamed low cigarette fire-retardant polyolefin, and steamed low cigarette fire-retardant polyolefin separates the crowded package of oxygen layer at the outer wall of shielding layer 5, and the outer wall of 6 inner sheaths is wrapped around to glass ribbon 7. The halogen-free low-smoke flame-retardant polyolefin oxygen-isolating layer has the advantages that the smoke quantity of combustion is low, a carbonized coke shell can be formed after combustion, continuous inward combustion is prevented, the glass ribbon 7 is non-combustible, the flame retardant capability of the cable sheath can be further improved, and after the temperature is reduced, the carbonized coke shell can be combined to form a hard structure to prevent secondary fire.

In a preferred embodiment, the wrapping thickness of the glass ribbon 7 is 3-4 mm.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention. The present invention is intended to cover by those skilled in the art various modifications and adaptations of the invention without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention is subject to the claims.

Claims (10)

1. A cross-linked polyethylene insulated B1-grade flame-retardant power cable for rail transit, which is characterized by comprising:

a plurality of conductive cores (1);

the inorganic oxygen-isolating filling layer (2) is filled in the outer walls of the conductive cores (1) and is wrapped by a wrapping tape (4) to form a circular cross section;

the shielding layer (5) is coated on the outer wall of the wrapping tape (4);

the inner sheath (6) is extruded on the outer wall of the shielding layer (5);

the glass ribbon (7) is wrapped on the outer wall of the inner sheath (6);

the outer sheath (8) is extruded on the outer wall of the glass ribbon (7);

each conductive core (1) comprises a stranded conductor (11), an insulating layer (12) extruded outside the stranded conductor (11) and a mica tape (13) wrapped on the outer wall of the insulating layer (12);

a plurality of expansion ropes (3) are arranged in the inorganic oxygen-insulating filling layer (2), and the expansion ropes (3) are formed by twisting water-blocking ropes (31) and foaming layers (32).

2. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, wherein the water blocking cord (31) comprises a plurality of water blocking yarns, and the foam layer (32) is configured to be compressed after the water blocking cord (31) absorbs water and expands.

3. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 2, wherein the foam layer (32) comprises a PP foam strip, and the water blocking cord (31) and the PP foam strip are twisted to form the expansion cord (3).

4. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 3, wherein the water blocking rope (31) and the PP foaming strip are in a regular twisted structure of 1+ 6.

5. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, wherein the water blocking cord (31) is located in the middle of six PP foam strips.

6. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, wherein the wrapping tape (4) comprises a non-woven tape fluorophlogopite tape wound on the outer wall of the non-woven tape, and the lapping rate of the wrapping tape (4) is more than 40%.

7. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, wherein the shielding layer (5) comprises a longitudinally wrapped aluminum-plastic/copper-plastic composite tape.

8. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, wherein the inner sheath (6) and the outer sheath (8) comprise a halogen-free low smoke flame retardant polyolefin layer.

9. The cross-linked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, wherein the wrapping thickness of the glass ribbon (7) is 3-4 mm.

10. Crosslinked polyethylene insulated B1-grade flame retardant power cable for rail transit according to claim 1, characterized in that the insulation layer (12) is an extruded crosslinked polyethylene insulation layer.

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