CN219017268U

CN219017268U - Flame-retardant flexible cable for rail transit

Info

Publication number: CN219017268U
Application number: CN202222800949.2U
Authority: CN
Inventors: 王益国; 曹晨涛; 陆琴芳; 杨阳; 周勇; 毛建美; 周川; 王英; 李嘉诚
Original assignee: Wuxi Huamei Cable Co ltd
Current assignee: Wuxi Huamei Cable Co ltd
Priority date: 2022-10-24
Filing date: 2022-10-24
Publication date: 2023-05-12
Anticipated expiration: 2032-10-24

Abstract

The utility model relates to the technical field of electric wires and cables, in particular to a flame-retardant flexible cable for rail transit, which comprises the following components: the cable comprises a cable core, a first guide core, a second guide core and a filling rope filled between the first guide core and the second guide core, wherein the first guide core, the second guide core and the filling rope are wrapped by wrapping layers to form a round section; the shielding layer is coated on the outer wall of the wrapping layer; the outer sheath is extruded on the outer wall of the shielding layer; according to the utility model, the oval second guide cores distributed in the circumferential array are arranged on the outer wall of the round first guide core, and the long axes of the second guide cores are perpendicular to the axis connecting lines of the first guide core and the second guide core, so that when a cable is bent, a larger deformation space is formed between the first guide core and the second guide core, the cable is easy to bend, the stress is small, the cable is suitable for the laying environment in a narrow space, and the steel cores are arranged in the first guide cores, so that small-pitch stranding is not needed, the tensile property of the cable is improved, and the weight of the cable is reduced.

Description

Flame-retardant flexible cable for rail transit

Technical Field

The utility model relates to the technical field of wires and cables, in particular to a flame-retardant flexible cable for rail transit.

Background

Along with the improvement of electrification and intelligent degree of rail transit, electric equipment in a rail transit locomotive is more and more complex, the type and the energy demand of cables are more and more specialized, the characteristics are clear, the locomotive space is very limited, the cables are required to meet the requirements of self electricity, insulation, flame retardance, shielding and the like, and higher requirements on flexibility and weight are also required, and the external diameter is small and the structure is compact.

The track traffic cable mainly comprises a flexible mineral cable, a flame-retardant flexible cable, a fire-resistant cable, wires, lighting fixtures and the like, and flame retardance and flexibility are key requirements in cable type selection. For example, in the case of the most commonly used electric wires and cables used in the interior of a machine set, the diversity of connection devices and the narrow laying space are required, and the requirements on the tensile strength, the outer diameter and the softness of the cables are high. At present, a small-pitch conductor is generally adopted to twist so as to enable the softness of the cable to be better, but the weight of the whole cable is easy to be higher, and the tensile property of the cable is reduced, so that a steel core is added in the middle of the cable to improve the whole tensile property, when the cable is longer, the weight is also increased, the diameter of the required steel core is also increased, the outer diameter of the cable is increased, and the weight is further increased.

Disclosure of Invention

According to a first aspect of the object of the present utility model, there is provided a flame retardant flexible cable for rail transit, comprising:

the cable comprises a cable core, a first guide core, a second guide core and a filling rope filled between the first guide core and the second guide core, wherein the first guide core, the second guide core and the filling rope are wrapped by wrapping layers to form a round section;

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

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

the first guide cores and the wrapping layers are provided with a plurality of second guide cores distributed in a circumferential array, the second guide cores are tangent to the first guide cores, the sections of the first guide cores are circular, the sections of the second guide cores are elliptical, the axis connecting lines of the first guide cores and the second guide cores are defined to be first connecting lines, and the long axes of the second guide cores are perpendicular to the first connecting lines.

Preferably, the first conductive core comprises a conductor, an inner insulating layer and an outer insulating layer, and the conductor comprises a steel core copper conductor.

Preferably, the steel core copper conductor is stranded in a mode of 1+6 or 1+6+12, and the steel core is positioned at the center of the copper bare wire.

Preferably, the inner insulating layer is a polyethylene insulating layer, and the outer insulating layer is a polypropylene insulating layer.

Preferably, the second guide core comprises two bare copper wires and an elliptic insulating layer extruded on the outer walls of the two bare copper wires, and the two bare copper wires are not stranded in parallel on the elliptic insulating layer.

Preferably, the connecting line of the axes of the two copper bare wires is perpendicular to the long axis direction of the second guide core

Preferably, the filling rope is a flame retardant PP rope.

Preferably, the semi-conductive shielding layer outside the shielding layer is a fine copper wire braiding layer.

Preferably, the included angle between the braiding angle of the shielding layer and the axis of the cable is 45-60 degrees, and the braiding density is more than 80%.

Compared with the prior art, the flame-retardant flexible cable for track traffic has the remarkable advantages that:

according to the flame-retardant flexible cable for track traffic, the oval second guide cores distributed in the circumferential array are arranged on the outer wall of the round first guide core, and the long axes of the second guide cores are perpendicular to the axis connecting lines of the first guide cores and the second guide cores, so that when the cable is bent, a larger deformation space is formed between the first guide cores and the second guide cores, the cable is easy to bend, the stress is small, the cable is suitable for a laying environment in a narrow space, and the steel cores are arranged in the first guide cores, so that small-pitch stranding is not needed, the tensile property of the cable is improved, and the weight of the cable is reduced.

Drawings

Fig. 1 is a schematic cross-sectional structure of a flame retardant flexible cable for rail transit according to the present utility model.

Detailed Description

For a better understanding of the technical content of the present utility model, specific examples are set forth below, along with the accompanying drawings.

Referring to fig. 1, the present utility model proposes a flame retardant flexible cable for rail transit, comprising a first conductive core 1 and a second conductive core 2, a cable core 10 formed by a filling rope 3 filled between the first conductive core 1 and the second conductive core 2, a wrapping layer 4 wrapped around the outside of the filling rope 3, a shielding layer 5 arranged outside the wrapping layer 4, and an outer sheath 6 arranged outside the shielding layer 5.

In combination with the illustration, a plurality of second guide cores 2 distributed in a circumferential array are arranged between the first guide core 1 and the wrapping layer 4, the second guide cores 2 are tangent to the first guide core 1, the cross section of the first guide core 1 is circular, and the cross section of the second guide core 2 is elliptical.

In this embodiment, the axis line of the first guide core 1 and the second guide core 2 is defined as a first line, and the long axis of the second guide core 2 is perpendicular to the first line.

Therefore, when the cable is bent, the insulation layers of the first guide core 1 and the second guide core 2 are elastically deformed, so that the tensile stress applied to the conductor can be reduced, and meanwhile, the cable has better torsion resistance, and therefore the cable is enabled to achieve the effects of high flexibility, small outer diameter and high tensile resistance under the condition that the section size of the cable is not changed as much as possible.

In an alternative embodiment, the first conductor 1 comprises a conductor 11, an inner insulating layer 12 and an outer insulating layer 13, the conductor 11 comprising a steel core copper conductor.

Preferably, the steel core copper conductor is stranded in a 1+6 manner, with the steel core being centered in the copper conductor. Thus, the conductor 11 has a high tensile strength.

Optionally, the steel core copper conductor is twisted in a mode of 1+6+12, the number of single wires of each layer from the center layer to the outside is increased by 6, the twisting directions of adjacent layers are opposite, and the twisting direction of the outermost layer is right.

Specifically, the inner insulating layer 13 and the outer insulating layer 14 are extruded on the outer wall of the conductor 11 by adopting a double-layer co-extrusion process to form a closed sleeve structure with uniform thickness, so that the conductor has good insulativity.

Specifically, the inner insulating layer 13 is made of polyethylene material, and the outer insulating layer 14 is made of polypropylene material, so that the insulating layer still has better elasticity under the condition of good insulation. When the cable is bent, the first guide core 1 and the second guide core 2 generate mutual extrusion deformation, so that the stress of the conductor is reduced.

Specifically, the thickness ratio of the inner insulating layer 13 to the outer insulating layer 14 is 3:7 or 4:6.

Further, the second guide core 2 includes two bare copper wires 21 and an insulating layer 22 extruded outside the two bare copper wires 21. Wherein the insulating layer 22 has an elliptical cross section.

Alternatively, the bare copper wire 21 is an oxygen-free copper wire having the advantages of high conductivity, surface gloss, and the like.

Specifically, the two bare conductors 21 are not twisted in parallel, and the axis connecting line of the two bare copper wires 21 is parallel to the long axis of the second guide core 2, so that in the bending direction of the second guide core 2 (the diameter direction of the cable), a larger deformation space can be provided by deformation of the insulating layer 22, the tensile stress of the bare copper wires 21 is reduced, and the flexibility of the cable is improved.

Optionally, the insulating layer 22 is polypropylene, which has good insulation and elasticity, and is beneficial to improving the flexibility of the cable.

In order to make the whole cable core more round and smooth, a filling rope 3 is arranged between the first guide core 1 and the second guide core 2, and the filling rope is wrapped by a wrapping belt 4 to form a round section.

Specifically, the filling ropes 3 and the second guide cores 2 are distributed in a staggered manner, and the filling ropes 3 are flame-retardant PP ropes, have flame retardance and elasticity, so that the cable core 10 keeps the roundness and simultaneously is beneficial to keeping the overall flexibility of the cable.

Optionally, the wrapping layer 4 comprises a polyester tape wrapping layer, the number of wrapping layers of the polyester tape wrapping layer is two, and the wrapping lap rate is 45%.

Further, in order to prevent interference of electromagnetic field generated by the shielding layer 5 to the surrounding environment and action of fault current during use, the shielding layer 5 is preferably a fine copper wire braid layer.

Specifically, the included angle between the braiding angle of the fine copper wire braiding layer and the axis of the cable is 45-60 degrees, so that the hardness of the braiding layer is reduced, and the braiding layer is flexible.

Specifically, the weaving density of the fine copper wire weaving layer is more than 80%, and excellent shielding performance can be achieved.

Further, an outer sheath 6 is extruded on the outer wall of the shielding layer 5, and the outer sheath 6 is preferably an irradiation crosslinking type halogen-free low-smoke flame-retardant polyolefin insulating material.

In combination with the embodiment, the oval second guide cores distributed in a circumferential array are arranged on the outer wall of the round first guide core, and the long axes of the second guide cores are perpendicular to the axis connecting lines of the first guide core and the second guide core, so that when a cable is bent, a larger deformation space is formed between the first guide core and the second guide core, the cable is easy to bend, the stress is small, the environment with complex and limited space in rail transit is adapted, and a thin steel core is arranged in the first guide core, so that small-pitch twisting is not needed, the tensile property of the cable is improved, and the weight of the cable is reduced.

While the utility model has been described with reference to preferred embodiments, it is not intended to be limiting. Those skilled in the art will appreciate that various modifications and adaptations can be made without departing from the spirit and scope of the present utility model. Accordingly, the scope of the utility model is defined by the appended claims.

Claims

1. A flame retardant flexible cable for rail transit, comprising:

the cable comprises a first guide core (1), a second guide core (2) and a filling rope (3) filled between the first guide core (1) and the second guide core (2), wherein the first guide core (1), the second guide core (2) and the filling rope (3) are wrapped by a wrapping layer (4) to form a round section;

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

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

a plurality of second guide cores (2) distributed in a circumferential array are arranged between the first guide core (1) and the wrapping layer (4), the second guide cores (2) are tangential to the first guide core (1), the cross section of the first guide core (1) is circular, and the cross section of the second guide core (2) is elliptical;

and defining the axis connecting line of the first guide core (1) and the second guide core (2) as a first connecting line, wherein the long axis of the second guide core (2) is perpendicular to the first connecting line.

2. The flame retardant flexible electrical cable for use in rail transit of claim 1 wherein said first conductor (1) comprises a conductor (11), an inner insulating layer (12) and an outer insulating layer (13), said conductor (11) comprising a steel core copper conductor.

3. The flame retardant flexible cable for a rail transit of claim 2 wherein the steel core copper conductor is stranded in a 1+6 or 1+6+12 manner, the steel core being centered on the copper conductor.

4. The flame retardant flexible cable for rail transit of claim 2 wherein the inner insulation layer (12) is a polyethylene insulation layer and the outer insulation layer (13) is a polypropylene insulation layer.

5. The flame-retardant flexible cable for track traffic according to claim 1, wherein the second guide core (2) comprises two bare copper wires (21) and an elliptical insulating layer (22) extruded on the outer walls of the two bare copper wires (21), and the two bare copper wires (21) are not stranded in parallel on the elliptical insulating layer (22).

6. The flame-retardant flexible cable for railway traffic according to claim 5, wherein a line connecting the axes of the two bare copper wires (21) is perpendicular to the long axis direction of the second guide core (2).

7. The flame retardant flexible cable for rail transit of claim 1 wherein the filler rope (3) is a flame retardant PP rope.

8. The flame retardant flexible electrical cable for an railway traffic according to claim 1, wherein the shielding layer (5) is a fine copper wire braid.

9. The flame retardant flexible cable for rail transit of claim 8 wherein the angle of braiding of the shielding layer (5) is 45-60 ° with the cable axis and the braiding density is greater than 80%.