With the development of society, China's construction industry has also been booming, and there are more and more modern high-rise buildings. These new buildings have the advantages of complex functions, large scale and concentrated personnel, which can bring people a good experience. However, such buildings also have huge hidden dangers, especially fire hazards. Once there is a fire, all kinds of indoor furniture and decoration materials will produce a lot of toxic gases, which will not only affect people's evacuation and escape, but also restrict the normal development of fire fighting operations. In order to improve the building, we need to improve the performance of the air duct according to the specific requirements of the building. The following is an in-depth analysis of this problem.
In the design of HVAC engineering, when the ventilation pipe system passes through different fire zones, and the function realization of the pipe system in normal and fire conditions, it always brings a lot of complexity, which makes it relatively difficult to choose the appropriate pipe system.
In the actual project, the air duct always needs to have a certain fire performance in some parts, here we can achieve the fire protection of the air duct in many ways.
Fire test method
Without the help of fire damper, the fire resistance performance of air duct can be expressed in the following ways: Fire stability, integrity and insulation.
The loss of stability occurs when the suspension or fixing parts of the air duct can not keep the original position, and the section collapses. This performance requirement is not applicable to the section of internal fire air pipe in the furnace.
The loss of integrity is manifested as: cracks, holes or tears appear on the air duct, or cracks appear between the air duct and the floor (wall), resulting in flame or hot gas penetration. The integrity assessment of fixed or unfixed ducts in case of movement or deformation is included in this standard.
The loss of thermal insulation is shown as follows: the average temperature rise of the outer surface of the air duct section outside the furnace is more than 140 ° or the temperature rise of a single point is more than 180 ℃. This standard also points out that if the air duct is covered with flammable materials or has grease accumulated inside, it should also meet the fire protection requirements of the air duct.