Low-smoke halogen-free flame-retardant cable and manufacturing method thereof

Abstract

The invention relates to the field of cables, and in particular relates to a low-smoke halogen-free flame-retardant cable and a manufacturing method thereof. The low-smoke halogen-free flame-retardant cable comprises a conductive core, wherein an insulating layer is arranged outside the conductive core and has a three-layer structure; the outer layer is made of low-smoke halogen-free flame-retardant polyolefin; and the middle layer and the inner layer are made of cross-linked polyolefin. The insulating layer of the cable is designed into an asymmetrical three-layer structure, so that the insulating layer has low-smoke halogen-free flame retardancy, excellent tensile strength, breaking elongation and other comprehensive mechanical properties, and the insulating layer of the cable has high voltage-resistant level.

Description

technical field [0001] The invention relates to the field of cables, in particular to a low-smoke, halogen-free, flame-retardant cable and a preparation method thereof. Background technique [0002] With the improvement of people's awareness of environmental protection and the acceleration of my country's social and economic construction, low-smoke, halogen-free and flame-retardant cables are widely used in important departments and public places such as high-rise buildings, subways, power plants, nuclear power plants, and rail transit. When a fire breaks out, the cable does not release corrosive gas when burning, and has good light transmission, which is of great help to rescue work and can reduce casualties and property losses to a large extent. [0003] The cable insulation layer refers to the outer layer of the cable core that plays an insulating role in the cable structure. At present, the insulation layer of the cable is mainly composed of polymers. The insulating lay...

AI Technical Summary

Problems solved by technology

Although the addition amount of phosphorus-nitrogen flame retardants is significantly lower than that of inorganic flame retardants, adding about 30wt% can obtain a better flame retardant effect, but due to the compatibility and other problems still exist, its influence on the comprehensive mechanical properties of materials Negative effects cannot be ignored. On the other hand, phosphorus-nitrogen flame retardants are more suitable for the flame retardancy of nylon, PET and other engineering plastic systems, while the flame retardancy of polyolefin cable materials will cause problems such as increased smoke density.

[0006] In addition, in order to make the cable insulation layer withstand the short-term high temperature under the state of breaking and short circuit, currently the industry widely adopts the silane-grafted polyethylene material cross-linked by warm water as the insulation layer of the cable. One of the main disadvantages of this method is The boiling process is time-consuming and energy-consuming. At the same time, water is often introduced into the material during the boiling process. At the same time, water is often prone to penetrate into the insulating layer and the surface of the conductor during the boiling process, thereby reducing the insulation performance of the insulating layer and causing the conductor to be damaged. The surface is easy to oxidize and other problems, so that there will be certain safety hazards in the use of the cable

Thereby laying hidden dangers for the failure of the cable during use

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