CN-224232382-U - Water tree-resistant low-voltage environment-friendly flame-retardant cable for urban underground pipe gallery

Abstract

The low-voltage environment-friendly flame-retardant cable for the water tree of the urban underground pipe gallery is characterized by comprising four wire cores, a wrapping layer, tearing ropes, a moisture-proof layer and a sheath, wherein the cable is simple in structural design, a conductor adopts a 90-degree fan-shaped compressed shape, a water-blocking belt and aluminum belt longitudinal wrapping process structure is designed, two symmetrical tearing ropes are added for convenient construction, the cable is enabled to have excellent environment-friendly, moisture-proof and water-blocking performances, the cable is insulated and water-resistant, the cable is widely applied to new construction or upgrading reconstruction of the urban underground pipe gallery project, economic value and application value are quite considerable, the running safety and reliability of the urban smart power grid are greatly improved, the waterproof, moisture-proof, mechanical damage-resistant, corrosion-resistant and flame-retardant strong bending radius can be up to 15D installation and laying, and dark damage is difficult to occur, and later maintenance is convenient.

Inventors

• KUANG SONGWEN
• LU CHAOYAN
• ZHANG LIJUN

Assignees

• 恒飞电缆股份有限公司

Dates

Publication Date

20260512

Application Date

20250428

Claims (3)

1. 1. A water tree resistant low-voltage environment-friendly flame-retardant cable for urban underground pipe gallery is characterized by comprising four wire cores, a belting layer, a tearing rope, a moisture-proof layer and a sheath; Each wire core comprises a wire and an insulating layer, the wire is twisted and compressed by a plurality of copper conductors to form a sector-shaped cross section, the angular radian of the sector-shaped cross section of the wire is 90 degrees, the insulating layer is extruded on the conductor and made of polypropylene materials, and the cross section of a cable core assembly formed by combining all the wire cores is round; The four wire cores are coated into a cable core assembly by the tape layer, and the tape layer is a strip formed by sandwiching expansion water-resistant powder between two layers of non-woven fabrics; The moisture-proof layer is longitudinally wrapped on the wrapping tape layer, the moisture-proof layer is an aluminum plastic tape, a compact protection pipe is formed by welding the joint after the moisture-proof layer is longitudinally wrapped on the wrapping tape layer, and the height of the moisture-proof layer is 0.5mm after the moisture-proof layer is embossed by an embossing machine; the sheath layer is extruded on the moisture-proof layer, and the sheath layer is made of low-smoke halogen-free polyolefin elastomer material.
2. 2. The water tree resistant low voltage environment-friendly flame retardant cable for the urban underground pipe gallery, as claimed in claim 1, wherein the thickness of the strip material of the wrapping layer is 0.25mm, and the overlapping rate is more than or equal to 25% when the wrapping layer is overlapped and wrapped outside the cable core.
3. 3. A water tree resistant low voltage environment friendly flame retardant cable for use in urban underground pipe rack as claimed in claim 1 or 2, wherein a tear rope is provided between said tape layer and moisture barrier on opposite sides of the cross section of the cable core assembly.

Description

Water tree-resistant low-voltage environment-friendly flame-retardant cable for urban underground pipe gallery Technical Field The utility model relates to the technical field of cableway power cables, in particular to a water tree-resistant low-voltage environment-friendly flame-retardant cable for an urban underground pipe gallery. Background Currently, the cable systems of utility aisles may face the following major drawbacks and challenges in operation, which may affect power reliability, safety, and maintenance efficiency: 1. The underground pipe gallery is easy to seep water or accumulate water, and the long-term humid environment can cause the water tree phenomenon of the cable crosslinked polyethylene insulating layer to reduce the cable insulating property, so as to cause electric leakage or short circuit; 2. The cable working environment in the underground pipe gallery is easy to cause mechanical damage, partial discharge or direct short circuit can be possibly caused, the concealment is strong, and the fault positioning is difficult; 3. The materials are not properly selected, and corrosion-resistant and flame-retardant materials are not selected for the pipe gallery environment; 4. the cable bending radius is insufficient, so that hidden structural damage is easy to occur in the circuit during laying construction; 5. Because a large number of pipelines are gathered together during the later maintenance of the cable, the operation space is narrow, and the sheath is not easy to peel off when the electric structure is overhauled. In summary, the defects of the underground pipe gallery cable need to be comprehensively optimized from the viewpoints of design, materials, construction and the like, and the reliability and the toughness of the urban underground comprehensive pipe network can be improved by combining an environment-friendly ecological technology. Disclosure of Invention Aiming at the problems in the background art, the utility model provides the water tree-resistant low-voltage environment-friendly flame-retardant cable for the urban underground pipe gallery, which is waterproof, dampproof, mechanical damage-resistant, corrosion-resistant, high in flame retardance, difficult to cause hidden damage when being installed and paved with large bending radius, and convenient to maintain in the later period. In order to achieve the above purpose, the present utility model adopts the following technical scheme: A water tree resistant low-voltage environment-friendly flame-retardant cable for urban underground pipe gallery is characterized by comprising four wire cores, a belting layer, a tearing rope, a moisture-proof layer and a sheath; Each wire core comprises a wire and an insulating layer, the wire is twisted and compressed by a plurality of copper conductors to form a sector-shaped cross section, the angular radian of the sector-shaped cross section of the wire is 90 degrees, the insulating layer is extruded on the conductor and made of polypropylene materials, and the cross section of a cable core assembly formed by combining all the wire cores is round; The four wire cores are coated into a cable core assembly by the tape layer, and the tape layer is a strip formed by sandwiching expansion water-resistant powder between two layers of non-woven fabrics; The moisture-proof layer is longitudinally wrapped on the wrapping tape layer, the moisture-proof layer is an aluminum plastic tape, a compact protection tube is formed by welding the joint after the moisture-proof layer is longitudinally wrapped on the wrapping tape layer, so that the cable core assembly is tightly attached to the aluminum plastic tape of the moisture-proof layer to form a radial waterproof structure, the height of the moisture-proof layer is 0.5mm after the moisture-proof layer is embossed by an embossing machine, the moisture-proof layer is prevented from being broken when the cable is bent, and meanwhile, the moisture-proof layer and the outer sheath are fully bonded to form a good comprehensive protection layer, and the waterproof performance is very excellent; the sheath layer is extruded on the moisture-proof layer, the sheath layer is made of low-smoke halogen-free polyolefin elastomer material, is an environment-friendly flame-retardant sheath polymer material, and has the formula of EVA+AL (OH) 3 as a main material, and no heavy metal components such as lead, cadmium and the like in the formula, so that the pollution to water and soil can be avoided. The utility model further adopts the scheme that in order to realize the water blocking function and ensure the flexibility and the electrical property of the material, the thickness of the strip material of the wrapping layer is 0.25mm, the wrapping layer is overlapped and wrapped outside the cable core, and the overlapping rate is more than or equal to 25%. The utility model further provides a technical scheme that in order to facilitate operation when the moisture-