High-flame-retardant green environment-friendly light medium-voltage fire-resistant power cable

Abstract

The utility model belongs to the technical field of power cables, and relates to a high-flame-retardant green environment-friendly light medium-voltage fire-resistant power cable which sequentially comprises a flame-retardant sheath layer, a steel tape armoring layer, an outer flame-retardant wrapping tape, a fire-resistant tape layer, a fire insulation layer, an oxygen insulation layer, an inner flame-retardant wrapping tape and a thinned insulation cable core from outside to inside. The cable core is formed by twisting a plurality of strands of insulating single wires, and gaps among the insulating single wires are filled with flame-retardant fillers; each insulating single wire is composed of a conductor shielding layer, a polypropylene thickness-reduced insulating layer, an insulating shielding layer and a copper strip, wherein the conductor shielding layer, the polypropylene thickness-reduced insulating layer and the insulating shielding layer are co-extruded outside the copper conductor in sequence from inside to outside, and the copper strip is lapped outside the insulating shielding layer in an overlapped mode. The power cable is good in flame retardant property and fire resistance, the polypropylene thickness-thinned insulating layers are adopted in the insulating single wires, and the insulating layers are thinned, so that the outer diameter of the power cable is reduced in the cabling process, and compared with a traditional cross-linked polyethylene power cable, the power cable has the advantages that the cost is reduced, and the service life is prolonged. The high-flame-retardant green environment-friendly light-weight medium-voltage fire-resistant power cable provided by the utility model is lighter.

Description

Technical Field

[0001] This utility model belongs to the field of power cable technology, specifically relating to a high flame-retardant, green, environmentally friendly, lightweight, medium-voltage fire-resistant power cable. Background Technology

[0002] Power cables are mainly used in industries such as power, petroleum, chemical, and construction. When a fire occurs, two major problems arise: first, the burning cables produce large amounts of toxic smoke, hindering the safe and rapid evacuation of personnel; second, a fire disrupts the power supply, causing elevators, emergency lighting, automatic alarms, and disaster relief systems to malfunction, making rescue and evacuation extremely difficult. Therefore, ensuring the uninterrupted operation of power and communication lines for a certain period is crucial in the event of a fire.

[0003] Currently used fire-resistant cables are mainly low-voltage fire-resistant cables, which generally achieve fire resistance by wrapping mica tape around the conductor. With the continuous advancement of cable technology, environmentally friendly flame-retardant fire-resistant cables of various voltage levels have emerged. However, for medium-voltage cables, which require higher insulation quality and lower partial discharge levels, simply wrapping the conductor with mica tape cannot meet the electrical performance requirements. To achieve the fire-resistant performance of medium-voltage power cables, it is necessary to use halogen-free, low-smoke flame-retardant materials after the metal shielding process and to add a fire-resistant layer to the cable structure.

[0004] A search revealed patent number CN201110154716.3, which discloses a medium-voltage fire-resistant cable, providing a medium-voltage fire-resistant cable that is not easily damaged in an oxygen-rich, high-temperature combustion environment and has good fire resistance. This medium-voltage fire-resistant cable includes a conductor, on which a conductor shielding layer, an insulation layer, and an insulation shielding layer are sequentially extruded. Outside the insulation shielding layer, a metal shielding layer, a heat insulation layer, a fire-resistant layer, and an outer sheath are sequentially provided. The fire-resistant layer is a composite fire-resistant layer composed of an inner fire-resistant layer of ceramicized silicone rubber and an outer fire-resistant layer of shell-type polyolefin. However, the following defects exist:

[0005] ① The fire resistance performance of the cable was fully considered, and a combined fire-resistant layer consisting of an inner fire-resistant layer of ceramicized silicone rubber and an outer fire-resistant layer of shell-type polyolefin was used. The flame-retardant performance of the cable was not taken into consideration in the materials used.

[0006] ② The fire-resistant layer is made of ceramicized silicone rubber, which will burn when exposed to fire and does not have flame-retardant properties; and there is no other flame-retardant layer.

[0007] ③ The conductor does not use an irregularly shaped tightly stranded structure, resulting in a larger conductor diameter, which in turn leads to a larger cable diameter, increased cable cost, and makes it difficult to bend, causing difficulties in cable construction. Utility Model Content

[0008] The purpose of this utility model is to provide a high flame-retardant, green, environmentally friendly, lightweight, medium-voltage fire-resistant power cable, which solves the problems of harmful gases being produced after the cable burns and poor flame-retardant performance.

[0009] This utility model is achieved through the following technical solution:

[0010] This utility model discloses a high flame-retardant, green, environmentally friendly, lightweight medium-voltage fire-resistant power cable, which includes, from the outside to the inside, a flame-retardant sheath layer, a steel tape armor layer, an outer flame-retardant wrapping tape, a fire-resistant tape layer, a fire-resistant layer, an oxygen-barrier layer, an inner flame-retardant wrapping tape, and a cable core with reduced insulation.

[0011] The cable core is made of multiple insulated single wires twisted together, and the gaps between the insulated single wires are filled with flame-retardant filler.

[0012] The insulated single wire consists of, from the inside out, a conductor shielding layer co-extruded outside the copper conductor, a polypropylene insulation layer with reduced thickness, an insulation shielding layer, and a copper strip overlapping and wrapped around the insulation shielding layer.

[0013] Furthermore, the flame-retardant filler is made of alkali-free glass fiber rope.

[0014] Furthermore, the inner and outer flame-retardant wrapping tapes are made of overlapping and wrapping halogen-free, low-smoke, flame-retardant, and alkali-free glass fiber ribbons.

[0015] Furthermore, the oxygen barrier layer is a halogen-free, low-smoke, flame-retardant polyolefin oxygen barrier filler.

[0016] Furthermore, the fire-resistant layer is extruded from ceramicized polyolefin refractory material.

[0017] Furthermore, the fire-resistant strip layer is formed by overlapping and wrapping double-sided synthetic mica tape.

[0018] Furthermore, the steel strip armor layer is formed by wrapping two layers of galvanized steel strips with gaps.

[0019] Furthermore, the flame-retardant sheath layer is made of shell-type halogen-free low-smoke flame-retardant polyolefin extrusion.

[0020] Furthermore, the copper conductor is an irregularly shaped, tightly twisted round copper conductor.

[0021] Compared with the prior art, the present invention has the following beneficial technical effects:

[0022] This utility model discloses a high flame-retardant, green, environmentally friendly, lightweight medium-voltage fire-resistant power cable, which, from the outside to the inside, includes a flame-retardant sheath layer, a steel tape armor layer, an outer flame-retardant wrapping tape, a fire-resistant tape layer, a fire barrier layer, an oxygen barrier layer, an inner flame-retardant wrapping tape, and a thinned insulation cable core. It possesses a multi-layered flame-retardant structure, including a flame-retardant sheath layer, an outer flame-retardant wrapping tape, and an inner flame-retardant wrapping tape. In the event of a fire or other unexpected situation, these flame-retardant components can effectively slow the spread of flames along the cable, preventing the fire from rapidly spreading to other areas along the cable line, thus buying more time for firefighting and ensuring the safety of surrounding facilities.

[0023] Equipped with key structures such as fire-resistant strip, fire-resistant layer, and oxygen-barrier layer, the cable core inside the cable can maintain normal electrical performance for a certain period of time during a fire, even if the external flames burn for a long time or the environment is high temperature. This ensures that the power supply to the electrical facilities is uninterrupted, guaranteeing the uninterrupted operation of these devices that are related to life and property safety, and improving emergency response capabilities and safety assurance capabilities in emergency situations such as fires.

[0024] Because polypropylene insulation material has better electrical properties and temperature resistance than cross-linked polyethylene insulation material, its insulation layer can be thinned during the production of insulated single wires. This reduces the outer diameter of the power cable during cabling, making the high flame-retardant, environmentally friendly, lightweight medium-voltage fire-resistant power cable provided by this invention lighter than traditional cross-linked polyethylene power cables.

[0025] Because polypropylene insulation does not undergo cross-linking or produce waste gas during production, the insulation layer of individual wires can be recycled when the cable reaches the end of its service life. The cable does not produce harmful gases when burned, and it can maintain normal operation for a certain period after a fire, ensuring no smoke or toxic gas release during a fire, guaranteeing safe evacuation and smooth firefighting operations. Furthermore, after the cable is discarded, the insulation layer can be recycled and reused, better meeting the requirements of high flame retardancy, high fire resistance, halogen-free, low-smoke, and environmentally friendly high-voltage fire-resistant cables in engineering projects.

[0026] Furthermore, the outer flame-retardant wrapping of this utility model is made of alkali-free flame-retardant material, and the flame-retardant sheath layer is made of shell-type halogen-free low-smoke flame-retardant polyolefin. The gas produced in the event of a fire is non-toxic and has good light transmittance, allowing people at the fire scene to see the surrounding environment clearly and escape quickly.

[0027] Furthermore, the oxygen barrier layer uses halogen-free, low-smoke, flame-retardant oxygen barrier filler with a high oxygen index. When exposed to fire, it decomposes to release moisture that prevents the spread of flames, thus exhibiting excellent flame-retardant properties.

[0028] Furthermore, the fire-resistant layer is made of ceramicized polyolefin refractory material extruded. Located inside the steel strip armor layer, the fire-resistant layer can quickly conduct heat through the steel strip in the event of a fire, causing the fire-resistant layer to solidify into a ceramic shell. This hard shell provides better flame retardancy, fire resistance, fire prevention, and heat insulation, allowing for continuous power supply for a period of time in the event of a fire, thus better protecting life and property.

[0029] Furthermore, the insulated single wire includes a copper conductor, a conductor shielding layer co-extruded from the inside out, a polypropylene insulation layer, an insulation shielding layer, and a copper strip overlapping and wrapped around the insulation shielding layer.

[0030] The insulation layer of the insulated single wire is made of polypropylene, which has excellent high-temperature resistance and good electrical insulation properties; moreover, the production process does not require cross-linking, does not produce cross-linking byproducts, and reduces production energy consumption. At the end of the cable's life, the material can be recycled, conforming to the current environmental protection concept of recycling. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of this utility model;

[0032] The following are the labels in the diagram: 1. Copper conductor; 2. Insulated single wire; 3. Flame-retardant filler; 4. Inner flame-retardant wrapping tape; 5. Oxygen barrier layer; 6. Fire barrier layer; 7. Fire-resistant strip layer; 8. Steel strip armor layer; 9. Outer flame-retardant wrapping tape; 10. Flame-retardant sheath layer. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this utility model and are not intended to limit it; that is, the described embodiments are only a part of, and not all, of the embodiments of this utility model.

[0034] The components described and illustrated in the accompanying drawings and embodiments of this utility model can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of this utility model provided in the following drawings is not intended to limit the scope of the claimed utility model, but merely to illustrate one selected embodiment of the utility model. All other embodiments obtained by those skilled in the art based on the accompanying drawings and embodiments of this utility model without inventive effort are within the protection scope of this utility model.

[0035] It should be noted that the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that a process, element, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to the process, element, method, article, or apparatus.

[0036] The features and performance of this utility model will be further described in detail below with reference to the embodiments.

[0037] according to Figure 1 As shown, this utility model discloses a high flame-retardant, green, environmentally friendly, lightweight medium-voltage fire-resistant power cable, which includes, from the outside to the inside, a flame-retardant sheath layer 10, a steel tape armor layer 8, an outer flame-retardant wrapping layer 9, a fire-resistant tape layer 7, a fire-resistant layer 6, an oxygen-barrier layer 5, an inner flame-retardant wrapping layer 4, and a cable core; the cable core is made of multiple insulated single wires 2 twisted together, and the gaps between the insulated single wires 2 are filled with flame-retardant filler 3.

[0038] The insulated single wire 2 consists of, from the inside out, a copper conductor 1, a conductor shielding layer co-extruded outside the copper conductor 1, a polypropylene insulation layer with reduced thickness, an insulation shielding layer, and a copper strip overlapping and wrapped around the insulation shielding layer.

[0039] The copper conductor 1 is an irregularly shaped, tightly stranded round copper conductor with a small conductor diameter, and the cable diameter is also small.

[0040] The flame-retardant filler 3 is made of alkali-free glass fiber rope.

[0041] The inner flame-retardant wrapping tape 4 and the outer flame-retardant wrapping tape 9 are made of overlapping and wrapping halogen-free, low-smoke, flame-retardant, and alkali-free glass fiber ribbon.

[0042] The oxygen barrier layer 5 is extruded from halogen-free, low-smoke, flame-retardant polyolefin oxygen barrier filler.

[0043] The fire-resistant layer 6 is made of ceramicized polyolefin refractory material extruded.

[0044] The fire-resistant layer 7 is made by overlapping and wrapping double-sided synthetic mica tape.

[0045] The steel strip armor layer 8 is formed by wrapping two layers of galvanized steel strips with gaps.

[0046] The flame-retardant sheath layer 10 is made of halogen-free, low-smoke flame-retardant polyolefin through extrusion.

[0047] Outside the stranded multi-strand insulated single wire 2, from the inside out, it is successively covered with halogen-free low-smoke flame-retardant alkali-free glass fiber tape, high oxygen index oxygen barrier layer, ceramicized polyolefin, fire-resistant tape layer 7, halogen-free low-smoke flame-retardant alkali-free glass fiber tape, double-layer galvanized steel tape, and shell-type low-smoke halogen-free flame-retardant polyolefin.

[0048] Structurally, the cable features multi-layer flame-retardant protection, specifically designed with a flame-retardant sheath layer 10, an outer flame-retardant wrapping tape 9, an inner flame-retardant wrapping tape 4, and flame-retardant filler 3 between the insulated single wires 2. Compared with traditional medium-voltage fire-resistant cables, its flame-retardant system is more complete, which can more effectively prevent the spread of flames, greatly reduce the risk of fire spreading along the cable when a fire occurs, and improve the fire safety performance of the entire cable line.

[0049] In addition to the traditional fire-resistant strip layer 7, a fire-resistant layer 6 and an oxygen-barrier layer 5 are added, further enhancing the cable's resistance to fire. Even under prolonged flame combustion, the cable can maintain its integrity, ensuring normal power transmission and providing more reliable power support for emergency rescue, personnel evacuation, and the operation of critical equipment at fire scenes.

[0050] The presence of oxygen barrier layer 5 can prevent oxygen from contacting the insulation material and conductor inside the cable, further reducing the possibility of the insulation material being oxidized at high temperatures, thereby maintaining the stability of insulation performance, extending the service life of the cable, and providing better protection for the normal operation of the cable even in extreme situations such as fire.

[0051] The flame-retardant sheath layer 10, oxygen barrier layer 5, inner flame-retardant wrapping tape 4, and outer flame-retardant wrapping tape 9 are made of environmentally friendly materials and do not contain halogens. During combustion, they do not produce dioxins, which can be carcinogenic like those produced by traditional PVC electrical wires, thus avoiding secondary pollution to the environment and human health, and meeting the stringent environmental protection requirements of modern society.

[0052] The sheath does not contain heavy metals such as lead and cadmium that are harmful to the human body. It will not pollute the soil or water sources during the use and disposal of the cable. In addition, it has undergone rigorous toxicity tests, and mice were unharmed under the specified experimental conditions, reducing the potential harm to the ecological environment.

[0053] Insulated single wire 2 uses a thinned polypropylene insulation layer, with copper tape wrapped around the outside of the insulation shielding layer. This reduces the cable's weight while ensuring insulation performance, making the cable lighter and easier to install and lay. Simultaneously, the copper tape wrapping not only enhances the mechanical strength of the insulated single wire but also provides electromagnetic shielding, reducing interference from external electromagnetic fields on internal signals and improving signal transmission quality and stability.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this utility model. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this utility model should be covered within the protection scope of the claims of this utility model.

Claims

1. A high flame-retardant, environmentally friendly, lightweight, medium-voltage fire-resistant power cable, characterized in that, From the outside to the inside, it includes a flame-retardant sheath layer (10), a steel strip armor layer (8), an outer flame-retardant wrapping tape (9), a fire-resistant strip layer (7), a fire-resistant layer (6), an oxygen-barrier layer (5), an inner flame-retardant wrapping tape (4), and a cable core with reduced insulation. The cable core is made of multiple insulated single wires (2) twisted together, and the gaps between the insulated single wires (2) are filled with flame-retardant filler (3). The insulated single wire (2) consists of a conductor shielding layer co-extruded from the inside out to the outside of the copper conductor (1), a polypropylene thickness-reduced insulation layer, an insulation shielding layer, and a copper strip overlapping and wrapped around the insulation shielding layer.

2. The high flame-retardant, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The flame-retardant filler (3) is made of alkali-free glass fiber rope.

3. The high flame-retardant, green, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The inner flame-retardant wrapping tape (4) and the outer flame-retardant wrapping tape (9) are made of overlapping and wrapping halogen-free, low-smoke, flame-retardant, and alkali-free glass fiber ribbon.

4. The high flame-retardant, green, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The oxygen barrier layer (5) is a halogen-free, low-smoke, flame-retardant polyolefin oxygen barrier filler.

5. The high flame-retardant, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The fireproof layer (6) is made of ceramicized polyolefin refractory material extruded.

6. The high flame-retardant, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The fire-resistant layer (7) is made by overlapping and wrapping double-sided synthetic mica tape.

7. The high flame-retardant, green, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The steel strip armor layer (8) is formed by wrapping two layers of galvanized steel strips with gaps.

8. The high flame-retardant, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The flame-retardant sheath layer (10) is made of shell-type halogen-free low-smoke flame-retardant polyolefin extrusion.

9. The high flame-retardant, environmentally friendly, lightweight medium-voltage fire-resistant power cable according to claim 1, characterized in that, The copper conductor (1) is a non-circular tightly stranded round copper conductor.

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