Characteristics of fan case

5. There are two types of fan cases: fire exhaust type and ventilation type. The fire smoke exhaust type adopts high-temperature resistant structural plates, and the electric motor and transmission components are all installed at the outer end of the fan case, which can discharge high-temperature smoke above 280 ℃ and operate continuously for more than 100 minutes.

Fan cases are divided into two types: smoke exhaust type and ventilation type, including centrifugal and axial flow type, BF fan cases.

Key points for selecting fan cases

1. The selected control parameters for the fan case include air volume, total pressure, efficiency, noise, and motor power. There are centrifugal and axial flow types.

2. The ventilation fan is equipped with a fan box, which is beneficial for noise reduction.

When selecting a ventilation fan, consideration should be given to the air leakage loss and calculation error of the pipeline system, as well as the negative deviation of the actual air volume and air pressure of the ventilation fan. Generally, a safety factor of 1.05-1.1 air volume and 1.10-1.15 air pressure is adopted. But it should not be too large to prevent the ventilation fan from operating in a low efficiency zone for a long time.

4. Pay attention to the matching relationship between the resistance characteristics of the pipeline network and the characteristics of the ventilation fan. To ensure stable operation of the ventilation system, the fan should be operated near its high efficiency point, with its operating point located to the right of the peak point of total pressure in the performance curve (i.e. on the high air volume side, and generally at 80% of the peak point of total pressure).