When selecting a fan, first based on the two basic parameters of the required fan's air volume and total pressure, the model and number of the fan can be determined through the dimensional performance table of the fan (relevant data is available in the product manual of each fan). In this case, more than one product may meet the requirements; At this point, combined with the purpose, process requirements, and usage scenarios of the fan, the type, model, and structural material of the fan should be selected to meet the required working conditions, striving to make the rated flow and pressure of the fan as close as possible to the process requirements, so as to make the operating point of the fan close to the high-efficiency zone of the fan's characteristics during operation.

The principles of a drying oven are as follows:

1. Before selecting a ventilation fan, it is important to understand the production and product quality situation of the domestic ventilation industry, such as the variety, specifications, and special uses of the produced ventilation fans, the development and promotion of new products, and fully consider the requirements in order to select the best fan.

2. Choose ventilation fans for different purposes based on the different physical and chemical properties of the gas conveyed by the ventilation fan. If transporting explosive and flammable gases, explosion-proof ventilation fans should be selected; Dust removal or coal powder conveying should choose dust removal or coal powder ventilation fans; For conveying corrosive gases, anti-corrosion ventilation fans should be selected; High temperature ventilation fans should be selected for working or transporting high-temperature gases in high-temperature environments.

3. When there are two or more types of ventilation fans available for selection on the performance chart of ventilation fan selection, priority should be given to selecting fans with higher efficiency and smaller fan numbers; A type with a larger adjustment range should also be compared and decided after weighing the pros and cons.

4. If the diameter of the selected fan impeller is much larger than that of the original fan impeller, in order to utilize the original motor shaft, bearings, and supports, it is necessary to calculate the starting time of the motor, the strength of the original fan components, and the critical speed of the shaft.

5. When selecting a centrifugal fan, when the motor power used is less than or equal to 75KW, a valve for starting only can be omitted. When selecting a centrifugal boiler induced draft fan to discharge high-temperature flue gas or air, a valve for starting should be installed to prevent overload during cold operation.

6. For ventilation systems with noise reduction requirements, ventilation fans with high efficiency and low impeller circumferential speed should be selected first, and they should be operated at high efficiency points; Corresponding noise reduction and vibration reduction measures should also be taken based on the propagation mode of noise and vibration generated by the ventilation system. The vibration reduction measures for ventilation fans and electric motors can generally adopt vibration reduction foundations, such as spring dampers or rubber dampers.