Fire-resistant wires and cables are the general term for wires and cables with fire-resistant properties, which are usually divided into two types: flame-retardant wires and cables and fire-resistant wires and cables. It is easy for ordinary people to confuse the concepts of flame-retardant cables and fire-resistant cables. Although flame-retardant cables have many advantages that are more suitable for chemical companies, such as low halogen, low smoke and flame retardant. But in general, fire-resistant cables can replace flame-retardant cables, but flame-retardant cables cannot replace fire-resistant cables. Here is a brief introduction to their differences and characteristics.
1. The difference in principle:
The principle of fire-resistant cables is different from that of flame-retardant cables. The flame-retardant principle of halogen-containing cable is based on the flame-retardant effect of halogen, and the flame-retardant principle of halogen-free cable is to reduce the temperature of the water to extinguish the fire. Fire-resistant cables rely on the fire-resistant and heat-resistant properties of the mica material in the fire-resistant layer, and the cables also work normally in the event of a fire. The current representative fire-resistant cable ceramic cable, as an emerging technology, its principle is that this type of cable can form a self-supporting ceramic body in the flame, which has a certain strength, thermal shock resistance and good electrical performance. The integrity of the structure can be maintained within a certain period of time (0.5-2h) in a flame at a high temperature of 650～1000℃, which can give full play to the effect of "passive fire protection" and win valuable time for fire safety. And it has the characteristics of halogen-free, low smoke, low toxicity, self-extinguishing, environmental protection, and easy processing.
2. The difference between structure and material:
Fire-resistant cables and flame-retardant cables are also different in structure and materials.
The basic structure of flame-retardant cable is: the insulation layer is made of flame-retardant materials, the sheath and outer sheath are made of flame-retardant materials, and the tape and filling are made of flame-retardant materials.
The fire-resistant cable usually adds a fire-resistant layer between the conductor and the insulating layer. Therefore, theoretically, a fire-resistant layer can be added to the structure of the flame-retardant cable to form a flame-retardant and fire-resistant cable. This is not necessary. Because of the fire-resistant layer of fire-resistant cables, different refractory materials can usually be used to directly coat the wires. It can withstand long-term burning, even if the polymer at the place where the flame is applied is burned, the line can operate normally.
3. The advantages and disadvantages of the two:
The characteristic of flame retardant cable is to delay the spread of flame along the cable to prevent the fire from spreading. Because of its low cost, it is a large number of cable varieties used in fire-resistant cables. Regardless of whether it is a single cable or a bundled installation, the flame spread can be controlled within a certain range when the cable is self-burning, so it can avoid major disasters caused by fire and burn, thereby improving the fire protection level of the cable line.
The fire-resistant cable can maintain the normal operation for a certain period of time under the condition of flame burning, and can maintain the integrity of the line. The amount of acid smoke produced by fire-resistant cables is small when burning, especially the addition of ceramic refractory materials, which greatly improves the fire-resistant and flame-retardant performance, especially when burning, accompanied by water spray and mechanical blows, the cable can still maintain the circuit Complete operation.
Ceramic silicon rubber cables among the representative fire-resistant cables are mainly used in medium and low-voltage fire-resistant wires and cables. Ceramic silicon rubber has rubber elasticity at room temperature and will not become brittle and fall off like mica tape after fire. It can be sprayed , Vibration test. As a new type of environmentally friendly inorganic filler added to ceramic cables, the low-melting glass powder FR01 and FR02 developed by Anmi Micro-Nano have the physical characteristics of high-temperature melting, high viscosity, and vitrification or ceramicization. The low melting point glass powder with matching temperature is pre-added to the raw material of fired silicone rubber wire and cable. After high temperature impact, a layer of expansion will be formed on the metal surface to match the metal. The color is adjustable, oxidation resistance, reduction resistance, acid and alkali resistance, and super weather resistance. The protective layer. Therefore, the fire-resistant cable can still maintain the integrity of the circuit under the high temperature of the fire, so as to gain valuable time for saving lives and property.
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