The so-called customized High temperature resistant wire from china is a cable that can maintain normal operation for a certain time under the specified high-temperature conditions, or a cable that can maintain the integrity of the line under high-temperature conditions. According to the domestic production level and current situation of customized High temperature resistant wire from china, most of the production is high-temperature resistant wires of 0.6/1.0kv and below. It is stipulated in GB / t19666-2005 that under the rated voltage, the fire supply temperature of 0.6/1.0kv and below cables is 750 + 50 ℃, the fire supply time is 90min + cooling time is 15min, the 2A fuse is constantly or the indicator light is not on. The selection of conductor materials, mica tape, insulating material and auxiliary materials for customized High temperature resistant wire from china is described as follows.

1. Selection of conductor material and conductor core structure

The melting point of aluminum conductor is 685 ℃, and the fire supply temperature should reach 750 + 50 ℃ according to GB / T 19216. Obviously, aluminum conductor can not be used as high-temperature wire; The melting point of copper is above 1000 ℃, so it can be used as a conductor of customized High temperature resistant wire from china.

Although the copper wire with section of 1.0mm2 and below does not melt under high temperature, the wire core is too thin, which is easy to break due to local overheating and slight external influence, and lose the normal power on function. Therefore, the copper wire with section of 1.0mm2 and below is not recommended as customized High temperature resistant wire from china.

The soft structure bundle wire will cause great damage to the mica tape due to the unsmooth and flat conductor surface, and the performance of the customized High temperature resistant wire from china produced is unstable.

The cable sector core conductor with large section is not easy to be used as customized High temperature resistant wire from china, and the circular core conductor is suitable for fire-resistant cable. Because the surface of the circular structure is smoother than that of the fan-shaped structure, the stress of the mica belt is relatively uniform and will not cause damage to the mica belt. Moreover, the circular structure saves the mica belt and has low cost than the fan-shaped structure.

2. Selection of mica tape

According to the actual production situation, phlogopite and synthetic mica are mostly used. The high temperature resistance of synthetic mica is higher than that of phlogopite. Since the grading requirements for customized High temperature resistant wire from china are cancelled in the national standard, the high-temperature resistant mica tape can be selected according to the requirements of customers in actual production. Considering the safety of customized High temperature resistant wire from china and ensuring the quality stability of customized High temperature resistant wire from china, it is recommended to use synthetic mica.

3. Selection of insulating materials

PVC, PE, XLPE and other commonly used insulating materials for customized High temperature resistant wire from china are mostly used, but the effect of using PE and XLPE is better than that of PVC, because at the high temperature of 750 + 50 ℃, the insulating material of the cable has long been burned and does not exist, but the residual materials after combustion of different insulating materials have different effects on the mica tape. The following description is made:

The main components of PVC are PVC resin and CaCO3. According to its combustion mechanism, it adheres to the outside of the mica belt. The mixture of Cao CaCl2, its combustion solid residue, is in a relatively stable state and adheres to the outside of the mica belt. During the combustion process, it will produce internal stress and squeeze the mica belt, which will damage the mica belt and affect the fire resistance.

PE and XLPE are pure carbon hydrogen compounds with almost no filler. Their combustion products CO2 and water vapor naturally escape, and only a small amount of solid impurities remain on the mica belt, which will not cause damage to the mica belt. Therefore, it can be seen that although PVC, PE and XLPE can be used for fire-resistant insulation, the effect of using PE and XLPE is better than that of PVC.

4. Selection of auxiliary materials for customized High temperature resistant wire from china

As an auxiliary material for customized High temperature resistant wire from china, although tape wrapping and filling are not key materials, they should be based on the principle of minimum residue after combustion.