The concept between flame-retardant cables and fire-resistant cables is very easy to be confused. In fact, flame-retardant cables have many advantages that are more suitable for use in chemical companies, such as low halogen and low smoke flame retardant, but under general conditions, fire resistance Cables can replace flame-retardant cables, but flame-retardant cables cannot replace fire-resistant cables. Their main differences are:
1. Different principles
The principle between fire-resistant cables and flame-retardant cables is different. The halogen flame retardant principle of the halogen cable is mainly based on the halogen flame retardant effect. The principle of the halogen flame retardant cable is to rely on the precipitated water to reduce the temperature to quench the flame. The fire-resistant cable relies on the fire-resistant and heat-resistant performance of the mica material in the fire-resistant layer to ensure that the cable can work normally in the event of a fire.
Second, the difference in structure and material
The basic structure of flame retardant cable:
(1) The insulation layer is made of flame retardant materials
(2) Flame-retardant materials are used for the sheath and outer sheath
(3) Flame-retardant materials are used for wrapping and filling
The basic structure of fire-resistant cable:
Fire-resistant cables usually add a fire-resistant layer between the conductor and the insulating layer, so in theory, a fire-resistant layer can be added to the structure of the flame-retardant cable to form a cable that is both flame-retardant and fire-resistant. There is no need for this. Because the refractory layer of the refractory cable is usually multi-layered mica tape wrapped directly on the wire, it can withstand long-term burning, even if the polymer applied to the flame is burned, it can ensure the normal operation of the line.
3. Clear concepts, advantages and disadvantages of flame retardant cables, halogen-free cables, and fire-resistant cables
The characteristic of the flame retardant cable is to delay the flame spreading along the cable so that the fire does not expand. Because of its low cost, it is a type of cable that is widely used in fire-resistant cables; whether it is a single cable or a bundle of cables, the flame can be controlled to a certain extent when the cable is burning, and the flame can be avoided. Major disasters caused by fire resistance, thereby improving the fire protection level of cable lines.
The characteristics of halogen-free and low-smoke flame-retardant cables are not only good flame-retardant properties, but also the low-smoke halogen-free cable materials that do not contain halogen, have low corrosion and toxicity during combustion, and generate a small amount of smoke, thereby reducing The damage to people, instruments, and equipment is conducive to timely rescue in the event of a fire. Although it has good flame retardancy, corrosion resistance, and a small amount of smoke, its mechanical and electrical properties are slightly worse than ordinary cables.
Fire-resistant cables are mainly able to maintain normal operation for a certain period of time in the case of flame combustion, which can ensure the integrity of the line. When the fire-resistant flame-retardant cable burns, the amount of acid gas smoke is less, and the fire-retardant flame resistance can be greatly improved. Especially when burning, accompanied by water spray and mechanical shock, the cable can still maintain the complete use of the line.
Post time: Jul-08-2020