1. What is fire bridge? Fire bridge does not mean that the bridge can be fireproof, rather it should be flame retardant. At present, bridges in the market mainly include steel bridge, aluminum alloy bridge and glass fiber reinforced plastic bridge. After a fire, the bridge itself will not burn. Fire bridge is a common practice in the industry to spray fire-resistant coating on the surface. In short, the fire bridge is a common fire bridge + fire retardant coating. So what is fire retardant coating? The purpose of flame retardant coatings is to slow down the flame propagation of flammable materials by spraying coatings on the surface of flammable materials, so as to improve the fire resistance of materials or prevent combustion within a certain period of time. This kind of coating is called fire retardant coating or flame retardant. Coating. The fire protection principle of fireproof coating can be summarized into the following five points: (1) the fireproof coating itself is flame retardant or non combustible, so the protected substrate will not directly contact with the air, thus delaying the occurrence of ignition. Objects and reduce the burning rate. (2) In addition to inherent flame retardancy or non flammability, the fireproof coating also has low thermal conductivity and can delay the transfer of flame temperature to the protected substrate. (3) The fire retardant coating is thermally decomposed into non combustible inert gas, which dilutes the combustible gas decomposed by the protective material, and is not easy to burn or the combustion speed is reduced. (4) The nitrogen-containing fire retardant coatings decompose into no and NH3 groups, which combine with organic groups to interrupt chain reaction and reduce temperature. (5) expand the expanded fireproof coating and expand it to form a carbon foam insulation layer to seal the protected object, delay the heat and substrate transfer, and prevent the combustion of the object or reduce the strength due to the increase of strength. Temperature. Fire bridge in the ordinary bridge surface spraying a layer of fire retardant coating, play a flame retardant role! In fact, the bridge itself will not catch fire. The fire could be just a cable. The fireproof principle of fireproof coating is the thickness of fireproof bridge. According to the requirements of table 10 of JB / T 10216-2000 "electrical control and distribution cable bridge", the thickness gauge can be used to measure the thickness of plating larger than 12 μ m, hot coating greater than 65 μ m, spraying greater than 50 μ m, and fire prevention greater than 500 μ M.