The material enters the Classifying chamber through upper part of sorting device. Material falls on the rotating material spreader. Under the action of centrifugal force, it is evenly thrown around. Coarse particles are thrown to the inner wall of the powder separation room under the action of the high-speed airflow of the external fan, loses kinetic energy and slides down along the wall surface and discharged from the cavity at the bottom of the separator. The remaining finer particles are rolled up by the rotating and rising airflow, and pass through the blades of the classification rotor into the efficient cyclone separation, it is collected as a finished product.