‌The principle of the steel-faced magnesium fire and smoke exhaust composite duct primarily relies on the characteristics of its fire-resistant and insulating layer, which combines fire resistance, heat resistance, and insulation properties, making this material a new type of fire-resistant and insulating material. The design of this duct meets the requirements of GB/T17428-2009 for fire resistance integrity and insulation, ensuring that the duct maintains its structural and functional integrity during a fire, effectively preventing the spread of the fire. Additionally, the inner and outer protective layers of the duct are made of high-corrosion-resistant metal plates or corrosion-resistant aluminum foil, which not only enhances the durability of the duct but also extends its service life to over 30 years. The connection of the duct uses special angle steel flanges, which not only guarantees the strength of the connection but also makes the installation process more convenient.‌

During a fire, the primary role of the steel-faced magnesium fire and smoke prevention composite duct is to block the spread of flames and high-temperature gases through its fire-resistant, heat-resistant, and insulating properties, thereby protecting the internal structure of the building and the safety of personnel. The design principle of this duct is very simple; it primarily prevents the spread of fire by blocking air flow, as both the dense smoke and flames in a fire are spread by air flow. Through this mechanism, the steel-faced magnesium fire and smoke prevention composite duct plays a crucial role in the fire safety of buildings.