The product is in reference to international advanced powder technology, using Aerodynamics Research and development of new products, reasonable structure, good powder selecting effect, obvious effect of energy saving is preferred to improve product yield and quality are grinding system after execution of new cement standard. Technical characteristics: 1, the material of "one divides into three layers of" i.e. coarse grain (d>150 ¦Ì m) separation layer, coarse grain (60 ¦Ì 2, advanced classification principle: combine many kinds of powder selecting principle of hierarchical configuration classification accuracy, a more accurate. Resonant frequencies of 3, using the principle and foundation of mechanical damping far in the powder selecting machine based natural frequency, resonance effects using exclusion phenomenon, the powder selecting machine adopts stepless speed regulation, convenient adjustment sensitive fineness. Technical parameters: