This is because of the impeller. The information of the housing and air intake is usually carbon steel Q235A, the spindle of the high-temperature fan is high-quality carbon steel No. 45, and the bearing box is usually cast iron HT200. Also available with cross-sectional steel (square steel. Channel steel), steel plate and other welding.
 

The use of intermediate layers in the manufacturing process is prohibited. Thick-skinned and other contrived information. The material on the surface of the part must not have obvious scratches. Aluminum must not have a partial scratch depth. The main functional indicator of the alternative data is that the rotating part or surface surface shall not use corrosion data below class B.

To satisfy the critical mechanical functional requirements of the parts. According to the purpose and conditions of the fan, the corrosion of the medium, the temperature of the medium, the dust content of the transported gas, the explosion-proof function and the economics of the data should be considered.