Meles MLEX assembled fireproof air duct is composed of fireproof insulation board, fireproof rock wool as insulation layer and inorganic ceramic fiber board as fireproof layer, which is automatically compounded by mechanization and assembly line technology. Thickness of galvanized steel plate ≥275g/m? The density of fireproof rock plate is ≥ 100kg/㎡, the combustion performance is Grade A, the thermal conductivity is ≤0.043w/m.k, and the fire resistance limit is 1-3 hours.