We are no strangers to wires and cables. We often see or use them in our life, and the insulation layer of cables, like the protective layer, shielding layer, sheath layer and conductor core, is the necessary basic component of wires and cables. It ensures that the current or electromagnetic wave and light wave transmitted by the conductor core only propagates along the conductor and does not flow to the outside, and ensures the safety of external objects and personnel. What is the difference between the insulating materials of wires and cables?

The first is plastic insulated cable. It has the advantages of good insulation performance, simple manufacturing process and low price. It can replace rubber insulation whether exposed or through pipe. The disadvantage is that it has poor adaptability to the climate, becomes hard and brittle at low temperature, and the plasticizer is easy to volatilize under high temperature or sunlight to accelerate the aging of insulation.

The second is rubber insulated cables, generally BX and BLX, which are used in specific scenarios.

The third is neoprene insulated cable. Now, with the development of technology, ordinary rubber wires below 35mm2 are replaced by neoprene insulated cables. It is characterized by good oil resistance, not easy to mold, no delayed combustion, good climate adaptability, slow light aging process, aging time about twice that of ordinary rubber insulated cable, and is suitable for outdoor laying. Since the mechanical strength of the insulating layer is weaker than that of ordinary rubber, it is not recommended for pipe laying.

The fourth is overhead insulated cable, which has excellent light aging resistance. It is mainly used in places with high groundwater level and overflow of chemical corrosive liquid. When the number of cables is small and it is inconvenient to be buried underground, this cable is particularly suitable for the reconstruction of urban distribution cable road.

The fifth kind of PVC insulated and sheathed power cable has 1kV and 6kV poles. The main advantages are simple manufacturing process, no limitation of laying height difference, light weight, good bending performance, simple joint fabrication, oil resistance, acid-base corrosion resistance, no flame retardation, internal armor structure, so that the steel strip or steel wire is free from corrosion and the price is cheap. Especially when the line height difference is large, or when it is laid in the bridge slot box, or when it is directly buried in chemically corrosive soil containing acid and alkali, plastic cable should be selected. The disadvantage is that the insulation resistance is lower than that of oil immersed insulated cable, the dielectric loss is higher, 1kV important circuit cable, and polyvinyl chloride insulated power cable should not be used.

The sixth kind of rubber insulated power cable. It has good bending performance and can be laid in severe cold climate. It is especially suitable for horizontal height difference and vertical laying of laying lines. It is not only suitable for fixed laying lines, but also for fixed laying lines that move regularly. The power supply circuit of mobile electrical equipment shall adopt rubber insulated and rubber sheathed flexible cable.

The seventh kind of metal sheathed mineral insulated cable. It is high temperature resistant, with copper or aluminum outer sheath and magnesium oxide insulation. It is suitable for high temperature, high humidity, flammable and explosive environments with AC rated voltage of 500V (DC voltage of 1000V) and below in iron and steel industry, power plants, oil depots, high-rise buildings, nuclear power plants, oil production platforms, cold storage, etc. Its long-term working environment temperature can reach 250 ℃ ~ 400 ℃. It is an ideal high-temperature resistant cable.