Railway cable

Abstract

The application provides a railway special cable and relates to the technical field of cables.The application comprises a conductor, an insulating layer arranged outside the conductor, a waterproof layer arranged outside the insulating layer, and an outer sheath arranged outside the waterproof layer, wherein a conductor shielding layer is further arranged between the conductor and the insulating layer, an insulating shielding layer and a metal shielding layer are further arranged between the insulating layer and the waterproof layer, and an armored layer is arranged between the waterproof layer and the outer sheath.The application has good electrical insulation performance and good waterproof and flame-retardant performance.

Description

Technical Field

[0001] This invention relates to the field of cable technology, and more specifically to a railway-specific cable. Background Technology

[0002] With the large-scale construction of passenger dedicated lines and high-speed railways in my country, and the further increase in the scale of construction, there is an objective need to use a large number of 27.5kV railway special cables. On the one hand, the use of 27.5kV switchgear requires cable entry and exit lines, and on the other hand, cable entry and exit lines have more advantages than overhead lines in terms of saving land and aesthetic layout.

[0003] Unlike the 26 / 35kV cables widely used in my country's current power system, the 27.5kV cable, as a special cable for my country's electrified railways, has certain unique characteristics. The 27.5kV cable must have high reliability to meet the requirements of the complex railway environment. High reliability is reflected in the cable being waterproof, flame-retardant, and having good electrical insulation performance. Summary of the Invention

[0004] The purpose of this invention is to develop a railway-specific cable with good electrical insulation properties and good waterproof and flame-retardant properties.

[0005] This invention is achieved through the following technical solution:

[0006] A railway-specific cable, comprising:

[0007] conductor;

[0008] An insulating layer is disposed on the outside of the conductor;

[0009] A waterproof layer is installed on the outside of the insulation layer;

[0010] The outer sheath is located on the outside of the waterproof layer;

[0011] The conductor is further provided with a conductor shielding layer between the conductor and the insulation layer, and an insulation shielding layer and a metal shielding layer are further provided between the insulation layer and the waterproof layer. An armoring layer is provided between the waterproof layer and the outer sheath.

[0012] Optionally, the conductor shielding layer and the insulating shielding layer are both semi-conductive materials, the insulating layer is made of XLPE material, the waterproof layer is made of polyethylene, the armor layer is made of copper strip, the metal shielding layer includes copper wire and copper strip, the metal shielding layer adopts the form of loosely wound copper wire and reverse-tied copper strip, and the outer sheath is made of flame-retardant polyvinyl chloride material.

[0013] Optionally, a water-blocking layer is provided between the metal shielding layer and the waterproof layer.

[0014] Optionally, the water-blocking layer comprises two layers of water-blocking yarn, with water-blocking grease filling the space between the two layers of water-blocking yarn.

[0015] Optionally, the cable is also fitted with multiple cylindrical fire-resistant sleeves made of fire-resistant material.

[0016] Optionally, the inner wall of the fire-resistant sleeve is provided with multiple fireproof strips and expansion strips at intervals, and the inner diameter of the fireproof strips and expansion strips is adapted to the outer diameter of the cable.

[0017] Optionally, the fireproof strip is made of ceramicized silicone rubber, and the expansion strip is made of expanded graphite.

[0018] Optionally, the flame arrestor sleeve is provided with a heat dissipation component, which includes a heat-conducting cylinder disposed inside the flame arrestor sleeve. Multiple inner heat-conducting rings connected to the heat-conducting cylinder are coaxially disposed on the inner wall of the flame arrestor sleeve, and multiple outer heat-conducting rings connected to the heat-conducting cylinder are coaxially disposed on the outer wall of the flame arrestor sleeve. The inner diameter of the inner heat-conducting ring is adapted to the outer diameter of the cable.

[0019] Optionally, the flame arrestor sleeve has a hollow cavity structure, the heat-conducting cylinder is disposed in the cavity, and except for the heat-conducting cylinder, the remaining cavities of the flame arrestor sleeve are filled with refractory fibers.

[0020] Optionally, the fire-arresting sleeve includes a first ring sleeve and a second ring sleeve. The first ring sleeve and the second ring sleeve are semi-cylindrical in shape and structure. The first ring sleeve and the second ring sleeve are respectively provided with connecting plates arranged parallel to their axial direction at both ends. The two connecting plates at both ends of the first ring sleeve are respectively bolted to the two connecting plates at both ends of the second ring sleeve.

[0021] The beneficial effects of this invention are:

[0022] This invention features excellent electrical insulation, waterproofing, and flame retardant properties. In particular, the fire-arresting sleeve effectively blocks fire, preventing its axial propagation along the cable. The ceramicized silicone rubber fire-resistant strips form a hard ceramicized shell upon contact with fire, creating a sealed space between adjacent strips. The expansion strip between adjacent strips expands upon contact with fire, filling the gap and extinguishing the fire. The heat dissipation components on the fire-arresting sleeve, through the inner heat-conducting ring, heat-conducting cylinder, and outer heat-conducting ring, promptly dissipate heat from the inside of the sleeve, preventing fire recurrence. The fire-arresting sleeve is detachable and can be adapted to the cable's environment. In high-temperature environments or environments with fire hazards, the density of the fire-arresting sleeves can be increased by connecting multiple sleeves sequentially to extend the fire-arresting structure. Conversely, in environments with lower temperatures or no fire hazards, the density of the fire-arresting sleeves can be reduced. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a structural diagram of Example 1;

[0025] Figure 2 This is a structural diagram of Example 2;

[0026] Figure 3 This is a structural diagram of Example 3;

[0027] Figure 4 This is a diagram of the internal structure of the flame arrester sleeve;

[0028] Figure 5 This is a structural diagram of Example 4.

[0029] Reference numerals: 1. Conductor; 2. Conductor shielding layer; 3. Insulation layer; 4. Insulation shielding layer; 5. Metal shielding layer; 6. Waterproof layer; 7. Armoring layer; 8. Outer sheath; 9. Water-blocking layer; 10. Fire-resistant sleeve; 101. First ring sleeve; 102. Second ring sleeve; 103. Connecting plate; 11. Outer heat-conducting ring; 12. Heat-conducting cylinder; 13. Fire-resistant fiber; 14. Fireproof strip; 15. Expansion strip; 16. Inner heat-conducting ring. Detailed Implementation

[0030] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0031] The following disclosure provides many different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, the present invention provides examples of various specific processes and materials, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0032] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0033] Example 1

[0034] like Figure 1 As shown, the present invention discloses a railway-specific cable, which includes, from the inside out, a conductor 1, a conductor shielding layer 2, an insulation layer 3, an insulation shielding layer 4, a metal shielding layer 5, a waterproof layer 6, an armor layer 7, and an outer sheath 8.

[0035] The conductor shielding layer 2 and the insulating shielding layer 4 are both semi-conductive materials, the insulating layer 3 is made of XLPE (cross-linked polyethylene), the waterproof layer 6 is polyethylene, and the armor layer 7 is copper strip.

[0036] The outer sheath 8 is made of low-smoke, halogen-free, flame-retardant polyolefin sheath material, which can be flame-retardant polyvinyl chloride.

[0037] The metal shielding layer 5 includes copper wires and copper strips, which are loosely wound with copper wires and reverse-tied with copper strips.

[0038] Example 2

[0039] like Figure 2 As shown, this embodiment differs from Embodiment 1 in that a water-blocking layer 9 is also provided between the metal shielding layer 5 and the waterproof layer 6.

[0040] In the event of damage or breakage of the waterproof layer 6, or other situations that could allow water to penetrate it, the water-blocking layer 9 serves as a safety net to prevent water from entering. The water-blocking layer 9 comprises two layers of water-blocking yarn, with water-blocking grease filling the space between them.

[0041] Example 3

[0042] like Figure 3 and Figure 4 As shown, this embodiment differs from Embodiment 1 in that multiple fire-resistant sleeves 10 are provided on the outside of the cable.

[0043] The fire-resistant sleeve 10 is fitted onto the outer wall of the cable. The fire-resistant sleeve 10 is made of fire-resistant material and is cylindrical. The inner diameter of the fire-resistant sleeve 10 is slightly larger than the outer diameter of the cable. The inner wall of the fire-resistant sleeve 10 is provided with multiple fireproof strips 14 and expansion strips 15 at intervals. That is, an expansion strip 15 is provided between two adjacent fireproof strips 14 and a fireproof strip 14 is provided between two adjacent expansion strips 15. The multiple fireproof strips 14 and expansion strips 15 are arranged at equal intervals.

[0044] The fireproof strip 14 is made of ceramicized silicone rubber, and the expansion strip 15 is made of a material that expands when exposed to high temperatures, such as expanded graphite. The inner diameter of the fireproof strip 14 and the expansion strip 15 is slightly smaller than the outer diameter of the cable, so that when the fire-resistant sleeve 10 is fitted onto the outer wall of the cable, the fireproof strip 14 and the expansion strip 15 are in close contact to fix the fire-resistant sleeve 10.

[0045] The flame arrestor sleeve 10 has a hollow internal structure and a heat dissipation component is provided inside the flame arrestor sleeve 10. The heat dissipation component includes a heat conduction cylinder 12 located inside the flame arrestor sleeve 10. Except for the heat conduction cylinder 12, the remaining internal cavities of the flame arrestor sleeve 10 are filled with refractory fibers 13. The refractory fibers 13 can be aluminosilicate refractory fibers or polycrystalline mullite fibers.

[0046] The inner wall of the fire-arresting sleeve 10 is provided with multiple annular inner heat-conducting rings 16. The inner heat-conducting rings 16 are arranged at equal intervals in the axial direction of the fire-arresting sleeve 10 and are arranged in the gap between the fireproof strip 14 and the expansion strip 15. The inner diameter of the inner heat-conducting ring 16 is adapted to the inner diameter of the cable. The outer edge of the inner heat-conducting ring 16 extends into the fire-arresting sleeve 10 and connects with the inner wall of the heat-conducting cylinder 12.

[0047] Multiple outer heat-conducting rings 11 are coaxially arranged on the outer wall of the flame arrestor sleeve 10. The multiple outer heat-conducting rings 11 are arranged at equal intervals along the axial direction of the flame arrestor sleeve 10. The inner edge of the outer heat-conducting ring 11 extends inward into the flame arrestor sleeve 10 and connects with the outer wall of the heat-conducting cylinder 12. The heat-conducting cylinder 12, the inner heat-conducting ring 16, and the outer heat-conducting ring 11 are all made of materials with high thermal conductivity.

[0048] Example 4

[0049] like Figure 5 As shown, this embodiment improves the flame arrestor sleeve 10 into a detachable structure based on embodiment 3.

[0050] In this embodiment, the fire-arresting sleeve 10 includes a first ring sleeve 101 and a second ring sleeve 102. The first ring sleeve 101 and the second ring sleeve 102 are semi-cylindrical in shape and structure. The first ring sleeve 101 and the second ring sleeve 102 are respectively provided with connecting plates 103 arranged parallel to their axial direction at both ends. The two connecting plates 103 at both ends of the first ring sleeve 101 are bolted to the two connecting plates 103 at both ends of the second ring sleeve 102.

[0051] The clamping force of the first ring sleeve 101 and the second ring sleeve 102 on the cable can be adjusted by adjusting the tightness of the bolts. After the bolts are loosened, the flame arrestor sleeve 10 can be moved axially on the cable to adjust its position. Tightening the bolts can secure the position of the flame arrestor sleeve 10 on the cable.

[0052] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the technical solutions of the present invention. Any technical solution that can be implemented based on the above embodiments without creative effort should be considered to fall within the scope of protection of the patent of the present invention.

Claims

1. A railway-specific cable, characterized in that, include: conductor; An insulating layer is disposed on the outside of the conductor; A waterproof layer is installed on the outside of the insulation layer; The outer sheath is located on the outside of the waterproof layer; Among them, a conductor shielding layer is provided between the conductor and the insulation layer, an insulation shielding layer and a metal shielding layer are provided between the insulation layer and the waterproof layer, and an armoring layer is provided between the waterproof layer and the outer sheath; The cable is also fitted with multiple cylindrical fire-resistant sleeves made of fire-resistant material. The inner wall of the fire-resistant sleeve is provided with multiple fireproof strips and expansion strips at intervals. The inner diameter of the fireproof strips and expansion strips is adapted to the outer diameter of the cable. The fireproof strips are made of ceramicized silicone rubber, and the expansion strips are made of expanded graphite. The flame arrestor sleeve is equipped with a heat dissipation component, which includes a heat-conducting cylinder disposed inside the flame arrestor sleeve. Multiple inner heat-conducting rings connected to the heat-conducting cylinder are coaxially disposed on the inner wall of the flame arrestor sleeve, and multiple outer heat-conducting rings connected to the heat-conducting cylinder are coaxially disposed on the outer wall of the flame arrestor sleeve. The inner diameter of the inner heat-conducting ring is adapted to the outer diameter of the cable.

2. The railway-specific cable according to claim 1, characterized in that, The conductor shielding layer and the insulating shielding layer are both semi-conductive materials. The insulating layer is made of XLPE material. The waterproof layer is made of polyethylene. The armor layer is made of copper strip. The metal shielding layer includes copper wire and copper strip. The metal shielding layer adopts a copper wire loose winding and copper strip reverse binding form. The outer sheath is made of flame-retardant polyvinyl chloride material.

3. The railway-specific cable according to claim 1, characterized in that, A water-blocking layer is also provided between the metal shielding layer and the waterproof layer.

4. The railway-specific cable according to claim 3, characterized in that, The water-blocking layer comprises two layers of water-blocking yarn, with water-blocking grease filling the space between the two layers of water-blocking yarn.

5. The railway-specific cable according to claim 1, characterized in that, The flame arrestor sleeve has a hollow cavity structure, and the heat-conducting cylinder is located inside the cavity. Except for the heat-conducting cylinder, the remaining cavities of the flame arrestor sleeve are filled with refractory fibers.

6. The railway-specific cable according to claim 1, characterized in that, The fire-arresting sleeve includes a first ring sleeve and a second ring sleeve. The first ring sleeve and the second ring sleeve are semi-cylindrical in shape and structure. The first ring sleeve and the second ring sleeve are respectively provided with connecting plates arranged parallel to their axial direction at both ends. The two connecting plates at both ends of the first ring sleeve are respectively bolted to the two connecting plates at both ends of the second ring sleeve.

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