In the past, most flues were prefabricated with sulphoaluminate cement and alkali-resistant glass fiber mesh or ordinary silicate cement and steel wire mesh. Due to the mandatory provisions of the national standards "Code for Design of Residential Buildings" and "Code for Fire Protection Design of Buildings", the fire resistance limit of smoke exhaust pipes in residential buildings should not be lower than 1.00h, and it is difficult for cement prefabricated flue to meet the fire resistance limit requirement of not less than1.0h. In order to prevent the accumulation of grease in smoke exhaust pipes in residential buildings from becoming a fire hazard for a long time, at present, The smoke exhaust pipes are mostly high-strength fire-resistant smoke exhaust pipes (patent number: ZL200820064055.9) assembled with new patented technology and inorganic fire-resistant flue plates, and the type test must be carried out according to the national standard GB/T 17428-2009, and the fire resistance limit should be greater than1.0h; The invention has the characteristics of light weight, high strength, no deformation, good fire resistance, strong flexible impact resistance, easy installation, good sound insulation performance and no damage. Widely used in kitchen exhaust and bathroom exhaust of residential buildings and public buildings.