Cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable

Abstract

The invention discloses a cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable which comprises a cable core formed by twisting a plurality of cross-linked polyethylene insulated wire cores. Graphene fibers are filled in gaps of the cable core; an anti-aging rubber hose is arranged outside the cable core, and a plurality of V-shaped anti-extrusion heat dissipation grooves are formed in the outer surface of the anti-aging rubber hose; a crocheting mixed shielding layer is arranged outside the anti-aging rubber hose, a high-temperature fire-resistant synthetic crystal insulating tape is lapped outside the crocheting mixed shielding layer, a high-strength braided flame-retardant layer is lapped outside the high-temperature fire-resistant synthetic crystal insulating tape in an overlapping manner, a non-magnetic metal armor layer is arranged outside the high-strength braided flame-retardant layer, and a magnetic shielding layer is arranged outside the non-magnetic metal armor layer. And a ceramic silicone rubber oxygen insulation outer sheath is extruded outside the non-magnetic metal armor layer. The cable has excellent mechanical property, shielding property and flame retardance, and is economical and environment-friendly.

Description

Technical Field

[0001] The invention relates to the field of electric wires and cables, and in particular to a cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable. Background Art

[0002] At present, with the rapid development of my country's electric power industry, the use of wires and cables has also increased significantly, especially the power cables used in ultra-high voltage and extra-high voltage transmission lines. As the main force of power transmission, the transmission of backbone network power must be based on large-section power cables. The safe use of corresponding large-section power cables is crucial. In addition, fire is one of the main disasters that always threaten the safety of people's lives and property. Building fires are generally caused by aging electrical lines, among which wires and cables occupy an important position. Therefore, fire prevention has become the top priority at present, especially for some important properties, cultural relics, documents, etc. Once a fire occurs, the loss will be immeasurable. Therefore, the fire performance requirements for the power supply lines of these special "customers" are particularly important. Most of the existing cables have the defect of low fire resistance.

[0003] During long-term use, aging is prone to occur and the corrosion resistance is poor, which leads to damage of the insulation layer, thus affecting power transmission. In addition, ordinary power cables do not have fire-proof properties, which leads to safety accidents, causing serious casualties and social losses.

[0004] After the insulation layer made of conventional materials is powered on for a long time, the surface temperature of the cable will continue to rise, especially when the cable load is large, and flames may even be emitted from the inside of the cable, which not only affects the surrounding environment, but also easily causes fire accidents. It produces toxic and harmful gases during combustion, causing significant loss of life and property. Moreover, ordinary power cables are easily affected by external factors such as corrosion and erosion, resulting in poor protection of the insulation layer and easy damage, thereby shortening the service life of the power cable. In addition, ordinary power cables lack effective waterproof measures, and water penetrates into the cable from the terminal, causing the conductor to short-circuit, causing greater safety hazards. Summary of the invention

[0005] In order to overcome the deficiencies in the prior art, a cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable is provided.

[0006] To achieve the above-mentioned purpose, the present invention provides a cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable, comprising a cable core, wherein the cable core is formed by twisting a plurality of cross-linked polyethylene insulated wire cores; the gaps in the cable core are filled with graphene fiber ropes; an anti-aging rubber hose is provided outside the cable core, and a plurality of V-shaped anti-extrusion heat dissipation grooves are provided on the outer surface of the anti-aging rubber hose; a crocheted hybrid shielding layer is provided outside the anti-aging rubber hose, a high-temperature fire-resistant synthetic crystal insulating tape is wrapped outside the crocheted hybrid shielding layer, a high-strength braided flame-retardant layer is overlapped and wrapped outside the high-temperature fire-resistant synthetic crystal insulating tape, a non-magnetic metal armor layer is provided outside the high-strength braided flame-retardant layer, and a ceramic silicone rubber oxygen-insulating outer sheath is extruded outside the non-magnetic metal armor layer.

[0007] Preferably, the cross-linked polyethylene insulated core comprises a graphene aluminum alloy conductor, a cross-linked polyethylene insulation layer is extruded outside the graphene aluminum alloy conductor, a reinforced shielding layer is provided outside the cross-linked polyethylene insulation layer, and a ceramic silicone rubber oxygen-isolating inner sheath is extruded outside the reinforced shielding layer.

[0008] Preferably, the reinforced shielding layer includes a copper sheet, which is folded at a position deviating from its midline to form a double-layer structure and comprises an outer copper sheet and an inner copper sheet, the length of the outer copper sheet being greater than the length of the inner copper sheet, the outer copper sheet being wrapped around the outside of the entire reinforced shielding layer, and the inner copper sheet being pressed on the inside of the entire reinforced shielding layer.

[0009] Preferably, the copper sheet is provided with a plurality of pressed grooves on both the inner and outer surfaces of the folded portion thereof.

[0010] Preferably, the anti-aging rubber hose comprises a hose body, the inner side of the hose body is provided with an inner anti-aging coating, the outer side of the hose body is provided with an outer anti-aging coating, and the outer side of the outer anti-aging coating is provided with an anti-pressure layer.

[0011] Preferably, the compression-resistant layer comprises a high-elastic polyurethane sheath and a plurality of carbon fiber braided reinforcement cores arranged in the high-elastic polyurethane sheath.

[0012] Preferably, the crocheted mixed shielding layer is a mesh shielding layer crocheted using oxygen-free copper wires with a diameter of not less than 0.2 mm as warps and carbon fiber wires with a diameter of not less than 0.2 mm as wefts.

[0013] Preferably, the high-strength woven flame-retardant layer comprises a flame-retardant woven cloth layer, an aluminum base tape, and a high-temperature resistant ointment film, wherein the flame-retardant woven cloth layer is compounded on the front side of the aluminum base tape by an adhesive, and the high-temperature resistant ointment film is compounded on the back side of the aluminum base tape by an adhesive.

[0014] Preferably, the adhesive is a highly elastic flame-retardant resin.

[0015] Preferably, the non-magnetic metal armor layer is a stainless steel strip or an aluminum alloy strip.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The graphene aluminum alloy conductor has a very high strength of 130GPa (pressure unit, 1GPa = 1000MPa), a Young's modulus of about 1100GPa, and a fracture strength of about 125Gpa; the resistivity of graphene is only about 10nΩm (resistivity unit), and the conductivity is about 100 times that of copper; by evenly implanting graphene into the aluminum matrix, the mechanical properties and electrical properties of the aluminum conductor can be better matched, thereby meeting the needs of different national economic fields such as medium and high voltage power transmission and transformation, high-speed rail, and wind power generation for conductor materials; 2. Filled with graphene fiber rope, it has extremely high strength and good flexibility, so that the cable core can meet the requirements of high strength; 3. The shielding performance of the cable can be improved by adopting a double-layer folded structure to strengthen the shielding layer. In addition, the outer copper skin 5 and the inner copper skin have better wrapping performance, and the tearing resistance is higher under the same external force conditions, which reduces the probability of cracks and is conducive to extending the actual service life of the cable. 4. The carbon fiber braided reinforcement core in the compression layer has an extremely high strength-to-weight ratio, making the braided reinforcement core both light and strong, with excellent mechanical properties and stability, not easily corroded by chemical substances, and suitable for harsh environments; in addition, combined with the high-elastic polyurethane sheath, the tensile strength, tear strength and wear resistance of the cable are greatly enhanced, and the high-elastic polyurethane sheath still maintains good elasticity and elongation in a high hardness range, making the entire compression layer strong inside and elastic outside; 5. It is equipped with a crocheted hybrid shielding layer. The oxygen-free copper wire and carbon fiber wire are interwoven into a mesh structure through crocheting technology. This structure not only provides a good shielding effect, but also has a certain degree of flexibility and durability; the design of the mesh structure helps to improve the ventilation and heat dissipation of the shielding layer, which is especially important for cables with long-term stable operation; the high conductivity of the oxygen-free copper wire ensures good shielding performance, and the addition of carbon fiber wire may further enhance the strength and stability of the shielding layer; 6. The use of non-magnetic metal belts enhances the cable's fire resistance and ability to resist external impact, which can prevent the cable itself from interfering with other cables and prevent external magnetic fields from interfering with itself; 7. The ceramic silicone rubber oxygen-insulating outer sheath can form a dense and hard ceramic body under high temperature environment. This ceramic body can not only prevent the spread of flames, but also protect the normal operation of internal components under high temperature conditions, and can maintain the integrity of the circuit at a high temperature of 950°C; the ceramic body also has good fireproof and heat-insulating properties, which can effectively prevent heat transfer in a fire and protect the cable core from high temperature damage; in addition, the ceramicized silicone rubber sintered body has high hardness and strength, and has certain flexural strength and penetration strength; the main residue during the combustion process is silicon dioxide, which will not cause harm to the human body and the environment, and produces less smoke, which helps to improve the visibility of the fire scene, facilitate fire extinguishing work, and can be recycled and reused, which is economical and environmentally friendly, so that the cable can meet the CWZ level requirements in BS6387 (950°C fire resistance, spray and vibration test), GB12666.6 A level, GB31247 A level and other fire-resistant cable standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 A schematic diagram of the structure to strengthen the shielding layer; Figure 3 It is a schematic diagram of the structure of the anti-aging rubber hose; Figure 4 It is a schematic diagram of the structure of the crocheted hybrid shielding layer; Figure 5 Schematic diagram of the structure of the high-strength woven flame-retardant layer. DETAILED DESCRIPTION

[0018] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0019] like Figure 1 As shown, the present invention provides a cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable, comprising a cable core, which is formed by twisting a plurality of cross-linked polyethylene insulated wire cores; Among them, the cross-linked polyethylene insulated core includes a graphene aluminum alloy conductor 1, which has very high strength, with a strength of 130GPa (pressure unit, 1GPa = 1000MPa), a Young's modulus of about 1100GPa, and a breaking strength of about 125Gpa; the resistivity of graphene is only about 10nΩm (resistivity unit), and the conductivity is about 100 times that of copper; by uniformly implanting graphene into the aluminum matrix, the mechanical properties and electrical properties of the aluminum conductor can be better matched, thereby meeting the demand for conductor materials in different national economic fields such as medium and high voltage power transmission and transformation, high-speed rail, and wind power generation; in addition, the strength of the aluminum alloy can be effectively improved after the graphene is compounded with the aluminum alloy.

[0020] A cross-linked polyethylene insulation layer 2 is extruded outside the graphene aluminum alloy conductor 1, a reinforced shielding layer 3 is provided outside the cross-linked polyethylene insulation layer 2, and a ceramic silicone rubber oxygen-isolating inner sheath 4 is extruded outside the reinforced shielding layer 3. The ceramic silicone rubber can form a dense and hard ceramic body under high temperature conditions. This ceramic body can not only prevent the spread of flames, but also protect the normal operation of internal components under high temperature conditions, and can maintain the integrity of the circuit at a high temperature of 950°C; the ceramic body also has good fireproof and heat-insulating properties, which can effectively prevent heat transfer in a fire and protect the cable core from high temperature damage; In this embodiment, the gaps in the cable core are filled with graphene fiber ropes 5, which have extremely high strength and good flexibility, so that the cable core can meet the requirements of bearing high strength; an anti-aging rubber hose 6 is provided outside the cable core, and a plurality of V-shaped anti-extrusion heat dissipation grooves 7 are provided on the outer surface of the anti-aging rubber hose; a crocheted mixed shielding layer 8 is provided outside the anti-aging rubber hose, and a high-temperature fire-resistant synthetic crystal insulating tape 9 is wrapped around the crocheted mixed shielding layer 8. The crystal insulating tape is a synthetic mica tape, which is divided into single-sided and double-sided. Alkali-free glass cloth is selected as a reinforcement layer. At the same time, a polyester film with moisture-proof function is bonded to the alkali-free glass cloth, and the polyester film is coated with a flame retardant; this structure not only ensures that it has moisture-proof functional characteristics compared with traditional mica tapes, but also further improves the flame retardant properties of the entire synthetic mica tape; a high-strength woven flame retardant layer 10 is wrapped around the high-temperature fire-resistant synthetic crystal insulating tape 9, and the overlap rate is not less than 85%; a non-magnetic metal armor layer 11 is provided outside the high-strength woven flame retardant layer , a ceramicized silicone rubber oxygen-isolating outer sheath 12 is extruded outside the non-magnetic metal armor layer. Similarly, the ceramicized silicone rubber can form a dense and hard ceramic body under high temperature conditions. This ceramic body can not only prevent the spread of flames, but also protect the normal operation of internal components under high temperature conditions, and can maintain the integrity of the circuit at a high temperature of 950°C; the ceramic body also has good fireproof and heat-insulating properties, which can effectively prevent heat transfer in a fire and protect the cable core from high temperature damage; in addition, the ceramicized silicone rubber sintered body has high hardness and strength, and has certain flexural strength and penetration strength; the main residue during the combustion process is silicon dioxide, which will not cause harm to the human body and the environment, and produces less smoke, which helps to improve the visibility of the fire scene, facilitate fire extinguishing work, and can be recycled and reused, which is economical and environmentally friendly, so that the cable can meet the CWZ level requirements in BS6387 (950°C fire resistance, spray and vibration test), GB12666.6 Class A, GB31247 Class A and other fire-resistant cable standards.

[0021] In this embodiment, further optimization is performed, such as Figure 2 As shown, the reinforced shielding layer 3 includes a copper sheet, which is folded at a position deviating from its midline to form a double-layer structure and comprises an outer copper sheet 31 and an inner copper sheet 32, respectively. The length of the outer copper sheet is greater than that of the inner copper sheet, and the outer copper sheet is wrapped around the outside of the entire reinforced shielding layer, while the inner copper sheet is pressed on the inside of the entire reinforced shielding layer. By adopting a double-layer folded structure for the reinforced shielding layer, the shielding performance of the cable can be improved, and the wrapping performance of the outer copper sheet 5 and the inner copper sheet is better, and the tearing resistance is higher under the same external force conditions, which reduces the probability of cracks and is beneficial to extending the actual service life of the cable.

[0022] In this embodiment, the copper sheet is provided with a plurality of grooves 33 on the inner and outer surfaces of the folded portion thereof. The grooves are designed to increase the mutual extrusion capability of the outer copper sheet and the inner copper sheet under the wrapping pressure, thereby improving the closeness and integrity of the reinforced shielding layer, thereby better exerting the shielding effect.

[0023] In this embodiment, if Figure 3 As shown, the anti-aging rubber hose 6 includes a hose body 61, the inner side of the hose body 61 is provided with an inner anti-aging coating 62, the outer side is provided with an outer anti-aging coating 63, and the outer side of the outer anti-aging coating is provided with a pressure-resistant layer 64, which increases the pressure resistance of the cable inside, protects the cable core from being easily crushed and deformed, and protects the wire core; The compression-resistant layer includes a high-elastic polyurethane sheath 641 and a plurality of carbon fiber braided reinforcement cores 642 arranged in the high-elastic polyurethane sheath. The carbon fiber braided reinforcement core has an extremely high strength-to-weight ratio, which makes the braided reinforcement core both light and strong, with excellent mechanical properties and stability, not easily corroded by chemical substances, and suitable for harsh environments; in addition, combined with the high-elastic polyurethane sheath, the tensile strength, tear strength and wear resistance of the cable are greatly enhanced, and the high-elastic polyurethane sheath still maintains good elasticity and elongation in a high hardness range, so that the entire compression-resistant layer is strong inside and elastic outside.

[0024] In this embodiment, if Figure 3 As shown, a plurality of V-shaped anti-extrusion heat dissipation grooves are provided on the high elastic polyurethane sheath, which facilitates the heat dissipation of the cable and improves the anti-extrusion performance of the cable.

[0025] In this embodiment, if Figure 4 As shown, the crocheted hybrid shielding layer 8 is a mesh shielding layer crocheted with oxygen-free copper wire 81 with a diameter of not less than 0.2 mm as the warp and carbon fiber wire 82 with a diameter of not less than 0.2 mm as the weft; the oxygen-free copper wire and the carbon fiber wire are interwoven into a mesh structure through crochet technology, which not only provides a good shielding effect, but also has certain flexibility and durability; the design of the mesh structure helps to improve the ventilation and heat dissipation of the shielding layer, which is particularly important for cables with long-term stable operation; the high electrical conductivity of the oxygen-free copper wire ensures good shielding performance, and the addition of carbon fiber wire may further enhance the strength and stability of the shielding layer.

[0026] In this embodiment, if Figure 5 As shown, the high-strength woven flame-retardant layer 10 includes a flame-retardant woven fabric layer 101, an aluminum base tape 102, and a high-temperature resistant ointment film 103. The flame-retardant woven fabric layer is compounded on the front of the aluminum base tape by an adhesive, and the high-temperature resistant ointment film is compounded on the back of the aluminum base tape by an adhesive. The flame-retardant woven fabric not only has good flame-retardant properties, but also has high mechanical strength and strong stability in use, and is halogen-free, safe and environmentally friendly. In addition, the adhesive is a highly elastic flame-retardant resin, which makes the high-strength woven flame-retardant layer have excellent flame-retardant properties and good corrosion resistance; The entire high-strength braided flame-retardant layer combines the flame-retardant properties of the flame-retardant braided cloth, the structural strength of the aluminum base tape, and the heat-resistant protection of the high-temperature resistant grease film, which greatly improves the performance of the cable.

[0027] In this embodiment, the non-magnetic metal belt is a stainless steel belt or an aluminum alloy belt, so that the fire resistance and external impact resistance of the cable are enhanced, which can prevent the cable itself from interfering with other cables and prevent the external magnetic field from interfering with itself.

[0028] In summary, through the above improvements, this cable has excellent mechanical properties, shielding, flame retardancy, economy and environmental protection, so that the cable can meet the CWZ level requirements in BS638 (950℃ fire resistance, spray and vibration test), GB12666.6 Class A, GB31247 Class A and other fire-resistant cable standards.

[0029] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the principle of the present invention, and these should also be regarded as belonging to the protection scope of the present invention.

Claims

1. Cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable, including a cable core, characterized in that: The cable core is formed by twisting a plurality of cross-linked polyethylene insulated wire cores; the gaps in the cable core are filled with graphene fiber ropes (5); an anti-aging rubber hose (6) is provided outside the cable core, and a plurality of V-shaped anti-extrusion heat dissipation grooves (7) are provided on the outer surface of the anti-aging rubber hose; a crocheted mixed shielding layer (8) is provided outside the anti-aging rubber hose, a high-temperature fire-resistant synthetic crystal insulation tape (9) is wrapped outside the crocheted mixed shielding layer, a high-strength braided flame-retardant layer (10) is overlapped and wrapped outside the high-temperature fire-resistant synthetic crystal insulation tape, a non-magnetic metal armor layer (11) is provided outside the high-strength braided flame-retardant layer, and a ceramicized silicone rubber oxygen-isolating outer sheath (12) is extruded outside the non-magnetic metal armor layer.

2. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 1, characterized in that: The cross-linked polyethylene insulated wire core comprises a graphene aluminum alloy conductor (1), a cross-linked polyethylene insulation layer (2) is extruded outside the graphene aluminum alloy conductor, a reinforced shielding layer (3) is provided outside the cross-linked polyethylene insulation layer, and a ceramic silicone rubber oxygen-isolating inner sheath (4) is extruded outside the reinforced shielding layer.

3. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 2, characterized in that: The reinforced shielding layer (3) comprises a copper sheet, which is folded at a position deviating from its midline to form a double-layer structure and comprises an outer copper sheet (31) and an inner copper sheet (32), the outer copper sheet being longer than the inner copper sheet, the outer copper sheet being wrapped around the outside of the entire reinforced shielding layer, and the inner copper sheet being pressed against the inside of the entire reinforced shielding layer.

4. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 3, characterized in that: The copper sheet is provided with a plurality of pressing grooves (33) on both the inner and outer surfaces of the folded portion thereof.

5. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 1, characterized in that: The anti-aging rubber hose (6) comprises a hose body (61), the inner side of the hose body being provided with an inner anti-aging coating (62), the outer side of the hose body being provided with an outer anti-aging coating (63), and the outer side of the outer anti-aging coating being provided with an anti-pressure layer (64).

6. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 5, characterized in that: The pressure-resistant layer (64) comprises a high-elasticity polyurethane sheath (641) and a plurality of carbon fiber braided reinforcement cores (642) arranged in the high-elasticity polyurethane sheath.

7. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 1, characterized in that: The crocheted mixed shielding layer (8) is a mesh shielding layer crocheted using oxygen-free copper wires (81) with a diameter of not less than 0.2 mm as warps and carbon fiber wires (82) with a diameter of not less than 0.2 mm as wefts.

8. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 1, characterized in that: The high-strength woven flame-retardant layer (10) comprises a flame-retardant woven fabric layer (101), an aluminum base tape (102), and a high-temperature resistant ointment film (103), wherein the flame-retardant woven fabric layer is laminated to the front side of the aluminum base tape via an adhesive, and the high-temperature resistant ointment film is laminated to the back side of the aluminum base tape via an adhesive.

9. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 8, characterized in that: The adhesive is a highly elastic flame-retardant resin.

10. The cross-linked polyethylene insulated non-magnetic metal armored flame-retardant power cable according to claim 1, characterized in that: The non-magnetic metal armor layer (11) is a stainless steel strip or an aluminum alloy strip.

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