A power cable for coal mines

Abstract

The present invention discloses a power cable for coal mines, and relates to the technical field of power cables, specifically a power cable for coal mines, comprising a main cable core, the outside of which is sequentially provided with a first insulating layer, a first shielding layer, a first flame retardant and heat insulating layer, an oxygen insulating layer, a nylon braided layer, and a tensile layer from the inside to the outside, the inside of the first flame retardant and heat insulating layer is provided with a secondary cable core, and the inside of the tensile layer is provided with high-strength carbon fiber. The power cable for coal mines, through the coordinated use of a wear-resistant layer and a wear-resistant strip, the wear-resistant strip can isolate the power cable, avoid direct contact between the power cable and the ground, avoid direct friction between the power cable and the ground during movement, and improve the service life of the power cable, the first wear-resistant layer, the second wear-resistant layer, and the third wear-resistant layer inside the wear-resistant layer have good wear resistance, reduce the rate of wear on the surface of the power cable, and are not easily damaged when moving on the ground.

Description

Technical Field

[0001] The present invention relates to the technical field of power cables, in particular to a power cable for coal mines. Background Art

[0002] Power cables are cables used to transmit and distribute electrical energy. Power cables are commonly used in urban underground power grids, power station lead-out lines, internal power supply for industrial and mining enterprises, and underwater transmission lines across rivers and seas.

[0003] Mining cable is the abbreviation of coal mine cable. All mining cables are flame-retardant cables. The characteristic of flame-retardant cables is that they may be burned and unable to operate in the case of fire, but they can prevent the spread of fire. After the fire source is evacuated, the residual flame or residual burning can extinguish itself within a limited time. Therefore, the existing flame-retardant cables can only passively prevent the spread of fire, but cannot actively contain the fire. When the fire source is not evacuated, the mining cable will still burn and there will still be a risk of burning. Due to the particularly harsh working conditions of open-pit mining, coupled with the frequent movement of cables on the ground, the surface is worn, the insulation resistance decreases, and the internal structure of the cable is easily damaged during the dragging process, affecting the normal operation of power supply and electrical equipment. For this reason, we provide a coal mine power cable. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a power cable for coal mines, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a power cable for coal mines, comprising a main cable core, the outside of the main cable core is sequentially provided with a first insulating layer, a first shielding layer, a first flame retardant and heat-insulating layer, an oxygen insulation layer, a nylon braided layer, and a tensile layer from the inside to the outside, an auxiliary cable core is arranged inside the first flame retardant and heat-insulating layer, the inside of the tensile layer is provided with high-strength carbon fiber, the outside of the tensile layer is fixedly sleeved with a supporting skeleton, the inside of the supporting skeleton is filled with aerogel fire extinguishing agent, the outside of the aerogel fire extinguishing agent is fixedly connected with an ignition powder, the outside of the supporting skeleton is sequentially provided with a second flame retardant and heat-insulating layer and a wear-resistant layer, and the outer surface of the wear-resistant layer is fixedly connected with a wear-resistant strip.

[0006] Optionally, the number of the secondary cable cores is twelve and they are symmetrically distributed about the center of the main cable core, the exterior of the secondary cable core is coated with a second insulating layer, and the exterior of the second insulating layer is coated with a second shielding layer.

[0007] Optionally, the oxygen-insulating layer comprises a polyethylene oxygen-insulating layer, the outside of the polyethylene oxygen-insulating layer is wrapped with a mica tape layer, and the outside of the mica tape layer is wrapped with a ceramic powder layer.

[0008] Optionally, the anti-tensile layer is an insulating resin layer, and the anti-tensile layer is coated on the outside of the high-strength carbon fibers, and the high-strength carbon fibers are in a grid structure.

[0009] Optionally, an isolation plate is fixedly connected to the interior of the support frame, and the isolation plate divides the interior of the aerogel fire extinguishing agent into independent small chambers. The aerogel fire extinguishing agent is filled in the small chambers, and the aerogel fire extinguishing agent is symmetrically distributed about the center of the support frame.

[0010] Optionally, a small hole is opened on the outer surface of the support frame, the small hole is connected to the small chamber, the ignition charge is movably sleeved in the small hole, one end of the ignition charge is inserted into the aerogel fire extinguishing agent, and the other end of the ignition charge is flush with the outer surface of the support frame.

[0011] Optionally, the wear-resistant layer is divided into a first wear-resistant layer, a second wear-resistant layer and a third wear-resistant layer from the outside to the inside, the first wear-resistant layer is a nylon braided layer, the second wear-resistant layer is a chlorinated polyethylene layer, and the third wear-resistant layer is a polycarbonate layer.

[0012] Optionally, the wear-resistant strips are distributed in a spiral shape outside the wear-resistant layer, and the wear-resistant strips are a double helix structure.

[0013] The present invention provides a power cable for coal mines, which has the following beneficial effects:

[0014] 1. The power cable for coal mines uses a wear-resistant layer and a wear-resistant strip. The wear-resistant strip can isolate the power cable to avoid direct contact between the power cable and the ground, and to avoid direct friction between the power cable and the ground during movement, thereby increasing the service life of the power cable. The first wear-resistant layer, the second wear-resistant layer, and the third wear-resistant layer inside the wear-resistant layer have good wear-resistant properties, which reduce the rate of wear on the surface of the power cable and make it not easily damaged when moving on the ground.

[0015] 2. The power cable for coal mines is provided with a supporting frame, which can support the wire core inside the power cable, thereby improving the compression resistance of the power cable and preventing the wire core from breaking when being squeezed.

[0016] 3. The coal mine power cable is equipped with aerogel fire extinguishing agent. When a fire occurs, the flame will first melt the outer wear-resistant layer and the second flame-retardant insulation layer to expose the supporting skeleton. At this time, the flame will ignite the ignition powder, and then the ignition powder will ignite the aerogel fire extinguishing agent, so that the aerogel fire extinguishing agent will spray N2, CO2 and metal salt solid particles, which can actively contain the flame, play an active fire extinguishing role, and avoid damage to the internal battery core of the power cable.

[0017] 4. The power cable for coal mines has a tensile layer, and the tensile strength of the high-strength carbon fiber inside the tensile layer reaches 2500-4500Mpa, which has good tensile performance, avoiding the tensile breakage of the layer structure inside the power cable during the dragging process, and improving the tensile performance of the power cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the present invention;

[0019] Figure 2 It is a schematic structural diagram of a cross section of the present invention;

[0020] Figure 3 It is a schematic diagram of the structure inside the tensile layer of the present invention;

[0021] Figure 4 It is a schematic diagram of the structure of the support frame of the present invention;

[0022] Figure 5 It is a schematic structural diagram of a cross-section of the support frame of the present invention;

[0023] Figure 6 It is a schematic structural diagram of the wear-resistant layer of the present invention.

[0024] In the figure: 1. main cable core; 2. first insulation layer; 3. first shielding layer; 4. first flame retardant and heat insulation layer; 5. auxiliary cable core; 6. second insulation layer; 7. second shielding layer; 8. oxygen insulation layer; 9. nylon braided layer; 10. tensile layer; 11. high-strength carbon fiber; 12. supporting skeleton; 13. aerogel fire extinguishing agent; 14. isolation board; 15. ignition powder; 16. second flame retardant and heat insulation layer; 17. wear-resistant layer; 171. first wear-resistant layer; 172. second wear-resistant layer; 173. third wear-resistant layer; 18. wear-resistant strip. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0026] See also Figure 1 , Figure 2The present invention provides a technical solution: a power cable for coal mines, comprising a main cable core 1, the outside of the main cable core 1 is sequentially provided with a first insulating layer 2, a first shielding layer 3, a first flame retardant heat insulation layer 4, an oxygen insulation layer 8, a nylon braided layer 9, and a tensile layer 10 from the inside to the outside, the first insulating layer 2 and the first shielding layer 3 play the role of insulating and shielding the main cable core 1, so that the main cable core 1 can stably transmit electricity, the inside of the first flame retardant heat insulation layer 4 is provided with an auxiliary cable core 5, the number of the auxiliary cable cores 5 is twelve and they are symmetrically distributed about the center of the main cable core 1, the outside of the auxiliary cable core 5 is coated with a second insulating layer 6, the outside of the second insulating layer 6 is coated with a second shielding layer 7, the second insulating layer 6 and the second shielding layer 7 play the role of insulating and shielding the auxiliary cable core 5, so that the auxiliary cable core 5 can stably transmit electricity.

[0027] See also Figure 2 , Figure 3 The oxygen-isolating layer 8 comprises a polyethylene oxygen-isolating layer, a mica tape layer is wrapped around the outside of the polyethylene oxygen-isolating layer, a ceramic powder layer is wrapped around the outside of the mica tape layer, and the oxygen-isolating layer 8 can isolate oxygen and slow down the aging of the internal layer structure. The interior of the tensile layer 10 is provided with high-strength carbon fiber 11, and the tensile layer 10 is an insulating resin layer. The tensile layer 10 is coated on the outside of the high-strength carbon fiber 11, and the high-strength carbon fiber 11 has a grid structure. The tensile strength of the high-strength carbon fiber 11 inside the tensile layer 10 reaches 2500-4500Mpa, and it has good tensile performance, which can avoid the tensile fracture of the internal layer structure of the power cable during the dragging process.

[0028] See also Figure 2 , Figure 4 , Figure 5The outer part of the tensile layer 10 is fixedly sleeved with a support frame 12, and the interior of the support frame 12 is filled with an aerogel fire extinguishing agent 13. By setting the aerogel fire extinguishing agent 13, when a fire occurs, the aerogel fire extinguishing agent 13 is ignited to spray N2, CO2 and metal salt solid particles, which can actively contain the flame and play an active fire extinguishing role to avoid damage to the battery core inside the power cable. The interior of the support frame 12 is fixedly connected with an isolation plate 14, and the isolation plate 14 divides the interior of the aerogel fire extinguishing agent 13 into independent small chambers. The isolation plate 14 plays the role of separating the aerogel fire extinguishing agent 13 to prevent the aerogel fire extinguishing agent 13 from being ignited together, which is convenient The aerogel fire extinguishing agent 13 performs fire extinguishing in sections. The aerogel fire extinguishing agent 13 is filled in the small chamber. The aerogel fire extinguishing agent 13 is symmetrically distributed about the center of the supporting skeleton 12. The outside of the aerogel fire extinguishing agent 13 is fixedly connected with an ignition powder 15. By setting the ignition powder 15, the ignition powder 15 will be ignited when it contacts the flame, and then the aerogel fire extinguishing agent 13 will be ignited by the ignition powder 15, which can play an ignition role. The outer surface of the supporting skeleton 12 is provided with a small hole, the small hole is connected to the small chamber, and the ignition powder 15 is movably sleeved in the small hole. One end of the ignition powder 15 is inserted into the aerogel fire extinguishing agent 13, and the other end of the ignition powder 15 is flush with the outer surface of the supporting skeleton 12.

[0029] See also Figure 1 , Figure 6 The outside of the supporting skeleton 12 is provided with a second flame retardant insulation layer 16 and a wear-resistant layer 17 in sequence. The wear-resistant layer 17 is divided into a first wear-resistant layer 171, a second wear-resistant layer 172 and a third wear-resistant layer 173 from the outside to the inside. The first wear-resistant layer 171 is a nylon braided layer, the second wear-resistant layer 172 is a chlorinated polyethylene layer, and the third wear-resistant layer 173 is a polycarbonate layer. The first wear-resistant layer 171, the second wear-resistant layer 172 and the third wear-resistant layer 173 inside the wear-resistant layer 17 have good wear resistance, reduce the rate of surface wear of the power cable, and are not easily damaged when moving on the ground. The outer surface of the wear-resistant layer 17 is fixedly connected with a wear-resistant strip 18, which is spirally distributed on the outside of the wear-resistant layer 17 and has a double helix structure. The wear-resistant strip 18 can isolate the power cable, avoid direct contact between the power cable and the ground, avoid direct friction between the power cable and the ground during movement, and improve the service life of the power cable.

[0030] In summary, when the power cable for coal mine is in use, the wear-resistant strip 18 can isolate the power cable, avoid direct contact between the power cable and the ground, avoid direct friction between the power cable and the ground during movement, and improve the service life of the power cable. The first wear-resistant layer 171, the second wear-resistant layer 172, and the third wear-resistant layer 173 inside the wear-resistant layer 17 have good wear resistance and reduce the rate of surface wear of the power cable. The support skeleton 12 plays a supporting role to avoid the wire core from breaking when it is squeezed. When a fire occurs, the second flame-retardant and heat-insulating layer 16 can play a flame-retardant role to prevent the fire from spreading. When the wear-resistant layer 17 and the second flame-retardant and heat-insulating layer 16 are burned, the ignition powder 15 is ignited by the flame, and then the ignition powder 15 ignites the aerogel fire extinguishing agent 13, so that the aerogel fire extinguishing agent 13 sprays N2, CO2 and metal salt solid particles, which can actively contain the flame and play an active fire extinguishing role. The tensile strength of the high-strength carbon fiber 11 inside the tensile layer 10 reaches 2500-4500Mpa, and it has good tensile properties, which can avoid the tensile fracture of the layer structure inside the power cable during the dragging process. The oxygen barrier layer 8 can isolate oxygen and slow down the aging of the internal layer structure.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention; the terms "first", "second", and "third" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance. In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus.

[0032] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A power cable for coal mines, comprising a main cable core (1), characterized in that: The outside of the main cable core (1) is provided with a first insulating layer (2), a first shielding layer (3), a first flame retardant and heat-insulating layer (4), an oxygen-isolating layer (8), a nylon braided layer (9), and a tensile layer (10) in sequence from the inside to the outside; the inside of the first flame retardant and heat-insulating layer (4) is provided with a secondary cable core (5); the inside of the tensile layer (10) is provided with high-strength carbon fibers (11); the outside of the tensile layer (10) is fixedly sleeved with a support frame (12); the inside of the support frame (12) is filled with an aerogel fire extinguishing agent (13); the outside of the aerogel fire extinguishing agent (13) is fixedly connected with an ignition charge (15); the outside of the support frame (12) is provided with a second flame retardant and heat-insulating layer (16) and a wear-resistant layer (17) in sequence; the outer surface of the wear-resistant layer (17) is fixedly connected with a wear-resistant strip (18); An isolation plate (14) is fixedly connected to the interior of the support frame (12), and the isolation plate (14) divides the interior of the aerogel fire extinguishing agent (13) into independent small chambers. The aerogel fire extinguishing agent (13) is filled in the small chambers, and the aerogel fire extinguishing agent (13) is symmetrically distributed about the center of the support frame (12); The outer surface of the support frame (12) is provided with a small hole, the small hole is connected to the small chamber, the ignition powder (15) is movably sleeved in the small hole, one end of the ignition powder (15) is inserted into the aerogel fire extinguishing agent (13), and the other end of the ignition powder (15) is flush with the outer surface of the support frame (12); The aerogel fire extinguishing agent (13) sprays N2, CO2 and metal salt solid particles.

2. A power cable for coal mine according to claim 1, characterized in that: The number of the secondary cable cores (5) is twelve and they are symmetrically distributed about the center of the main cable core (1); the exterior of the secondary cable core (5) is coated with a second insulating layer (6); and the exterior of the second insulating layer (6) is coated with a second shielding layer (7).

3. A power cable for coal mine according to claim 1, characterized in that: The oxygen-insulating layer (8) comprises a polyethylene oxygen-insulating layer, the outside of the polyethylene oxygen-insulating layer is wound with a mica tape layer, and the outside of the mica tape layer is wrapped with a ceramic powder layer.

4. A power cable for coal mine according to claim 1, characterized in that: The anti-tensile layer (10) is an insulating resin layer, and the anti-tensile layer (10) is coated on the outside of the high-strength carbon fibers (11), and the high-strength carbon fibers (11) are in a grid-like structure.

5. A power cable for coal mine according to claim 1, characterized in that: The wear-resistant layer (17) is divided into a first wear-resistant layer (171), a second wear-resistant layer (172) and a third wear-resistant layer (173) from the outside to the inside, the first wear-resistant layer (171) is a nylon braided layer, the second wear-resistant layer (172) is a chlorinated polyethylene layer, and the third wear-resistant layer (173) is a polycarbonate layer.

6. A power cable for coal mine according to claim 1, characterized in that: The wear-resistant strips (18) are distributed in a spiral shape outside the wear-resistant layer (17), and the wear-resistant strips (18) are double helical structures.

Images