Do you know the advantages of mineral insulated cables?
In recent years, due to the rapid development of cities, the number of high-rise buildings has increased dramatically, and the demand for electricity in cities has also risen steadily. In such a densely populated key area, once a fire occurs, the consequences will be disastrous. Therefore, in China, relevant laws and regulations stipulate that in the fire protection design specifications of building projects, the fire protection system must use mineral insulated cables in order to pass the fire protection acceptance.
Mineral insulated cable is referred to as MI cable. When used as wiring, it is usually called magnesium oxide cable or fireproof cable in China. It is a copper core copper sheathed cable with mineral material magnesium oxide powder as insulation. Mineral insulated cable consists of two inorganic materials: copper conductor, magnesium oxide, and copper sheath.
Since the cable is made entirely of inorganic materials (metal copper and magnesium oxide powder), it will not cause fire itself, and it is impossible to burn or support combustion. Since the melting point of copper is 1083℃ and the melting point of magnesium oxide is 2800℃, this type of cable can continue to maintain power supply in a fire situation close to the melting point of copper, and is a truly fireproof cable. Superior performance is much better than traditional NH fire-resistant cables: The cable structure materials are all made of inorganic mineral materials. The cables do not release smoke or toxic gases in the burning flames; the discarded cables can also be recycled and reused without polluting the natural environment. Therefore, its green and environmentally friendly characteristics are higher than other commonly used cables.
With strong overload capacity, the normal operating temperature of mineral insulated cable can reach 250℃. Under special circumstances, the cable can maintain working for a short time at a temperature close to the melting point of the copper sheath. It is very suitable for laying in high-temperature places, such as metallurgy, boilers, glass kilns, blast furnaces and other environments. Its interception capacity is far greater than other cables, because magnesium oxide powder has a better conductor coefficient than plastic, so the same working temperature has a larger interception capacity. For lines above 16mm, one section can be reduced, and for places where people are not allowed to touch, two sections can be reduced.
Mineral insulated cables also have good bending characteristics. Traditional rigid fireproof cables (BTTZ) are difficult to bend and use. The minimum bending radius of mineral insulated flexible fireproof cables is 6 to 10 times the cable diameter, which reduces the space for installation layout, reduces installation costs, and is easier to lay.
Radiation-resistant and non-aging, mineral insulated flexible fireproof cable uses inorganic mineral insulation materials as insulation. Compared with conventional organic insulated cables (YJV, VV), it is not affected by radiation, the material will not age and deteriorate, and the insulation properties will not change; at the same time, the outer sheath of the cable is in the form of copper corrugation, which has excellent sealing, moisture-proof and corrosion-resistant properties. The service life of the cable can reach more than 70 years, which is 2-3 times the life of ordinary cables. Coupled with the inherent characteristics of the copper sheath, the grounding of the cable is better, so the lightning protection grounding measures are effectively implemented, thereby ensuring the safe and reliable operation of the electrical line.
High mechanical strength, impact resistance, metal sheath isolation type flexible fireproof cable The mineral insulation layer of the cable is provided with an aluminum metal layer on the outside, which has the effect of heat insulation, heat insulation, fire and water blocking, and can also prevent objects in the fire environment from impacting and damaging the cable insulation layer. In addition, the cable can be porcelainized. The fireproof layer will form a solid shell at 350°C, which effectively enhances the protection function of the cable.
Mineral insulated cables are special cables that must be used for fire protection in national important facilities, large public areas, high-rise buildings and other places. Their fire resistance, durability, safety, reliability and economy are irreplaceable by traditional power cables. Due to the many excellent characteristics of mineral insulated cables, they have been adopted by many domestic electrical design specifications or standards in recent years, and have also been used in many engineering projects in different industries. It can be expected that the use of this mineral insulated cable will increase significantly in the next ten years.
