A water-blocking fire-resistant medium voltage power cable

Abstract

The utility model discloses a kind of water-blocking fire-resistant medium-voltage power cable, specifically related to power cable technical field, including the inner core group, inner rubber layer, mica tape layer, aluminium-plastic composite tape layer, armoring layer and sheath layer sequentially arranged along radial direction, inner core group includes multiple groups of stranded wire core and the inner sleeve respectively sleeved on wire core, water-blocking glue layer is arranged between wire core in inner sleeve, and water-blocking powder layer is arranged between multiple inner sleeves in inner rubber layer. The water-blocking fire-resistant medium-voltage power cable provided by the utility model realizes the longitudinal waterproof of cable by water-blocking glue layer and water-blocking powder layer between multiple inner sleeves, and realizes the radial waterproof of multiple levels by inner sleeve, inner rubber layer, aluminium-plastic composite tape layer and sheath layer, and further enhances the fireproof performance of power cable by mica tape layer and aluminium-plastic composite tape layer, so as to enhance the applicability of power cable by improving waterproof and fireproof simultaneously.

Description

Technical Field

[0001] This utility model relates to the field of power cable technology, and more specifically to a water-resistant and fire-resistant medium-voltage power cable. Background Technology

[0002] Medium-voltage power cables refer to power transmission cables with a rated voltage range between 1kV and 35kV. They are mainly used in medium-voltage transmission lines in power distribution systems to transmit and distribute electrical energy.

[0003] According to patent publication number CN210722554U, published on June 9, 2020, a medium-voltage power cable is disclosed, including a protective structure and a core structure disposed within the protective structure; the core structure includes a conductive core, a first shielding layer is attached to the outer surface of the conductive core, an insulating inner layer is covered on the outer surface of the first shielding layer, an insulating outer layer is covered on the outer surface of the insulating inner layer, a second shielding layer is covered on the outer surface of the insulating outer layer, and a metal shielding layer is covered on the outer surface of the second shielding layer; the protective structure includes an insulating layer, an armor layer, and a sheath arranged sequentially from the inside out.

[0004] In the prior art, including the aforementioned patent, the use of a first and second shielding layer can effectively eliminate the problem of partial discharge in power cables. Combined with the armor layer and sheath, this effectively enhances the structural strength and protective effect of the power cable. However, in practical applications, such power cables have poor waterproof and fire-resistant properties. Due to the lack of corresponding water-blocking and fire-resistant layers, they are difficult to use in special environments. Utility Model Content

[0005] The purpose of this invention is to provide a water-resistant and fire-resistant medium-voltage power cable to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a water-resistant and fire-resistant medium-voltage power cable, comprising an inner core assembly, an inner rubber layer, a mica tape layer, an aluminum-plastic composite tape layer, an armor layer, and a sheath layer arranged sequentially along the radial direction. The inner core assembly includes multiple stranded wire cores and inner sleeves respectively fitted onto the wire cores. A water-resistant adhesive layer is provided between the wire cores in the inner sleeves, and a water-resistant powder layer is provided between the multiple inner sleeves in the inner rubber layer.

[0007] Preferably, a magnesium oxide ceramic fiber layer is filled between the aluminum-plastic composite strip layer and the armor layer.

[0008] Preferably, a shielding layer is filled between the aluminum-plastic composite tape layer and the mica tape layer.

[0009] Preferably, the mica strip layer comprises multiple spirally coiled main mica strips.

[0010] Preferably, the main mica strip has extension holes.

[0011] Preferably, the main mica tape has a folded edge, and when the aluminum-plastic composite tape layer is wound around multiple main mica tapes, it covers the folded edge, and the shielding layer fills the space between the main mica tape, the folded edge and the aluminum-plastic composite tape layer.

[0012] Preferably, the inner rubber layer is a cross-linked polyethylene sheath.

[0013] Preferably, the inner rubber layer is ceramicized silicone rubber.

[0014] Preferably, the shielding layer is a graphene-modified polyolefin.

[0015] Preferably, the water-blocking adhesive layer is a polyurethane adhesive.

[0016] In the above technical solution, the water-blocking and fire-resistant medium-voltage power cable provided by this utility model has the following beneficial effects: longitudinal waterproofing of the cable is achieved by using the water-blocking adhesive layer between the conductors and the water-blocking powder layer between multiple inner sheaths; multi-layer radial waterproofing is achieved through the inner sheath, inner rubber layer, aluminum-plastic composite tape layer and sheath layer; and the fire resistance of the power cable is further enhanced through the mica tape layer and aluminum-plastic composite tape layer. Therefore, the applicability of the power cable is enhanced by simultaneously improving waterproofing and fire resistance. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a schematic diagram of the overall cross-sectional structure provided for an embodiment of the present utility model;

[0019] Figure 2 This is a schematic diagram of the mica tape portion structure provided in an embodiment of the present utility model;

[0020] Figure 3 This is an enlarged structural diagram of point A provided in an embodiment of the present utility model;

[0021] Figure 4 This is an enlarged structural diagram of section B provided in an embodiment of the present utility model.

[0022] Explanation of reference numerals in the attached figures:

[0023] 1. Sheath layer; 2. Aluminum-plastic composite tape layer; 3. Main mica tape; 4. Inner rubber layer; 5. Core wire; 11. Armor layer; 12. Magnesium oxide ceramic fiber layer; 21. Shielding layer; 31. Folded edge; 32. Extension hole; 51. Inner sleeve; 52. Water-blocking adhesive layer; 53. Water-blocking powder layer. Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0025] like Figure 1-4 As shown, a water-blocking and fire-resistant medium-voltage power cable includes an inner core assembly, an inner rubber layer 4, a mica tape layer, an aluminum-plastic composite tape layer 2, an armor layer 11, and a sheath layer 1 arranged sequentially along the radial direction. The inner core assembly includes multiple stranded wire cores 5 and inner sleeves 51 respectively fitted onto the wire cores 5. A water-blocking adhesive layer 52 is disposed within the inner sleeves 51 between the wire cores 5, and a water-blocking powder layer 53 is disposed within the inner rubber layer 4 between the multiple inner sleeves 51. The longitudinal waterproofing of the cable is achieved by utilizing the water-blocking adhesive layer 52 disposed between the wire cores 5 and the water-blocking powder layer 53 disposed between the multiple inner sleeves 51. Multi-layer radial waterproofing is achieved through the inner sleeves 51, the inner rubber layer 4, the aluminum-plastic composite tape layer 2, and the sheath layer 1. The fire resistance of the power cable is further enhanced by the mica tape layer and the aluminum-plastic composite tape layer 2. Therefore, the applicability of the power cable is enhanced by simultaneously improving both waterproofing and fire resistance.

[0026] As a further technical solution provided by this utility model, a magnesium oxide ceramic fiber layer 12 is filled between the aluminum-plastic composite strip layer 2 and the armor layer 11.

[0027] Specifically, by utilizing the magnesium oxide ceramic fiber layer 12, excellent electrical insulation properties can be provided, preventing current leakage and short circuits. It also protects the cable for safe operation in high-temperature environments. Furthermore, the magnesium oxide ceramic fiber has good flame retardancy, improving the cable's fire resistance and enhancing its mechanical strength, preventing damage from external forces.

[0028] Furthermore, a shielding layer 21 is filled between the aluminum-plastic composite tape layer 2 and the mica tape layer.

[0029] Specifically, the shielding layer 21 is used to eliminate the problem of partial discharge in the power cable.

[0030] Furthermore, the mica belt layer comprises multiple spirally coiled main mica belts 3.

[0031] Specifically, by using multiple main mica strips 3 spirally wound, the elasticity of the mica strip layer is improved so that when the inner rubber layer 4 expands to a certain extent, the spirally wound main mica strips 3 can adapt to deformation and expansion. At the same time, the multiple spirally wound main mica strips 3 can also provide a certain tensile strength.

[0032] Furthermore, the main mica tape 3 has an extension hole 32.

[0033] Specifically, by utilizing the extension holes 32 opened on the main mica strip 3, the flexibility of the main mica strip 3 and the relative stability between the shielding layer 21 and the main mica strip 3 are improved.

[0034] Furthermore, the main mica tape 3 is provided with a folded edge 31. When the aluminum-plastic composite tape layer 2 is wrapped around multiple main mica tapes 3, it covers the folded edge 31, and the shielding layer 21 fills the space between the main mica tape 3, the folded edge 31 and the aluminum-plastic composite tape layer 2.

[0035] Specifically, by utilizing the folds 31 on multiple main mica tapes 3 to create a certain degree of isolation between the folds 31, the space between the main mica tapes 3, the folds 31, and the aluminum-plastic composite tape layer 2 can be used to fill the shielding layer 21. This reduces the problem of the shielding layer 21 shifting due to bending of the power cable, and the problem of partial shielding layer 21 loss. This improves the stability of the shielding layer 21 within the power cable.

[0036] Furthermore, the inner rubber layer 4 is a cross-linked polyethylene sheath.

[0037] Specifically, the anti-creep properties of the cross-linked polyethylene sheath are used to maintain continuous coating pressure on the water-blocking adhesive.

[0038] Furthermore, the inner rubber layer 4 is made of ceramicized silicone rubber.

[0039] Specifically, ceramicized silicone rubber exhibits high-temperature resistance, allowing it to operate continuously at extremely high temperatures. This provides a degree of insulation and protection against external high temperatures. Simultaneously, ceramicized silicone rubber possesses excellent electrical insulation properties.

[0040] Furthermore, the shielding layer 21 is a graphene-modified polyolefin.

[0041] Specifically, graphene-modified polyolefins can significantly improve the conductivity of polyolefins, thereby enhancing the shielding effect.

[0042] Furthermore, the water-blocking adhesive layer 52 is made of polyurethane adhesive.

[0043] Specifically, polyurethane adhesive has good elasticity and waterproof properties, and is wear-resistant and fire-resistant.

[0044] Working Principle: The cable achieves longitudinal waterproofing by utilizing the water-blocking adhesive layer 52 between the conductors 5 and the water-blocking powder layer 53 between multiple inner sheaths 51. Multi-layered radial waterproofing is achieved through the inner sheath 51, inner rubber layer 4, aluminum-plastic composite tape layer 2, and sheath layer 1. The mica tape layer and aluminum-plastic composite tape layer 2 further enhance the fire resistance of the power cable. Therefore, by simultaneously improving waterproofing and fire resistance, the applicability of the power cable is enhanced. Simultaneously, the folds 31 on the multiple main mica tapes 3 create a certain degree of isolation between them. The space between the main mica tapes 3, the folds 31, and the aluminum-plastic composite tape layer 2 can be used to fill the shielding layer 21, thereby reducing the problem of shielding layer 21 shifting or missing areas due to cable bending. This improves the stability of the shielding layer 21 within the power cable.

[0045] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A water-resistant and fire-resistant medium-voltage power cable, characterized in that, It includes an inner core group, an inner rubber layer (4), a mica tape layer, an aluminum-plastic composite tape layer (2), an armor layer (11), and a sheath layer (1) arranged in sequence along the radial direction. The inner core group includes multiple stranded wire cores (5) and inner sleeves (51) respectively sleeved on the wire cores (5). A water-blocking adhesive layer (52) is provided in the inner sleeve (51) between the wire cores (5), and a water-blocking powder layer (53) is provided in the inner rubber layer (4) between the multiple inner sleeves (51).

2. The water-resistant and fire-resistant medium-voltage power cable according to claim 1, characterized in that, A magnesium oxide ceramic fiber layer (12) is filled between the aluminum-plastic composite strip layer (2) and the armor layer (11).

3. The water-resistant and fire-resistant medium-voltage power cable according to claim 1, characterized in that, A shielding layer (21) is filled between the aluminum-plastic composite tape layer (2) and the mica tape layer.

4. A water-resistant and fire-resistant medium-voltage power cable according to claim 1, characterized in that, The mica belt layer includes multiple spirally coiled main mica belts (3).

5. A water-resistant and fire-resistant medium-voltage power cable according to claim 4, characterized in that, The main mica strip (3) has an extension hole (32).

6. A water-resistant and fire-resistant medium-voltage power cable according to claim 5, characterized in that, The main mica tape (3) is provided with a folded edge (31). When the aluminum-plastic composite tape layer (2) is wound around multiple main mica tapes (3), it covers the folded edge (31), and the shielding layer (21) is filled between the main mica tape (3), the folded edge (31) and the aluminum-plastic composite tape layer (2).

7. A water-resistant and fire-resistant medium-voltage power cable according to claim 1, characterized in that, The inner rubber layer (4) is a cross-linked polyethylene sheath.

8. A water-resistant and fire-resistant medium-voltage power cable according to claim 1, characterized in that, The inner rubber layer (4) is ceramicized silicone rubber.

9. A water-resistant and fire-resistant medium-voltage power cable according to claim 3, characterized in that, The shielding layer (21) is a graphene-modified polyolefin.

10. A water-resistant and fire-resistant medium-voltage power cable according to claim 1, characterized in that, The water-blocking adhesive layer (52) is a polyurethane adhesive.

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