The mill type PPS are designed for the fine or finest grinding of many materials of medium hardness and abrasiveness, such as:

  • Powder coatings
  • Chemicals
  • Vegetable products (dried vegetables, cocoa, soia, cereals, wood flours)
  • Pesticides

These mills have a high speed vertical axis rotor on which many vertical pins or hammers of suitable shape are fixed.
The grinding action is provided by impact against smooth or toothed lining and by friction between layers of the processed material.
The product is pneumatically discharged upwards, through an air classifier.
The special design with coaxial shafts of rotor and classifier mounted on suitable bearings provide a compact construction and an easy installation.
The dynamic microclassifier, with special shape and deflector, is suitable to obtain powders at a fineness up to 99% finer than 30 micron, with average diameter d50 adjustable in the range 2 – 20 micron with granulometry distribution in a narrow range.
Fineness adjustment is made by changing the speed of the classifier, the capacity of the suction blower, and the speed of the rotor.
The oversize not passing through the micro-classifier returns to the grinding area where it is further pulverized.
Only the product with the requested granulometry is collected after the mill.
The high flow of air (or other gas) and the mill’s design reduce the heat transfer to the product, compared with other type of pulverizing systems.


  • Mills type PPS can be fed with dry materials up to 10 mm.
  • Mills type PPS are suitable for contemporary grinding and cooling of raw materials ( food materials , chemicals products, vegetables)
  • In case of heat sensitive or flammable raw materials (cocoa, vegetables), it is possible to blow cold air or inert gas through the mill (nitrogen)
  • Screw feeder or Rotary valve feeder. For certain applications the raw material is fed pneumatically to the mill
  • Grinding rotor with pins or hammers made of special heat treated steel. Tungsten carbide tips available for abrasive materials
  • Smooth or toothed grinding lining
  • Coaxial shafts made in Cr.Ni. steel rotating on suitable bearings
  • The machine can be supplied in mild or stainless steel and with special wear resistant protection
  • Fast opening of grinding chamber with a hydraulic system that allows easy cleaning and spare parts changing
TYPE PPS300 PPS500 PPS750 PPS1000
Diameter of mill rotor mm 200 400 600 850
Power requirement of mill kW 7,5 11÷22 55÷75 90÷110
Power requirement of classifier kW 1,1 3÷5,5 7,5÷11 15
Hourly capacity Kg/h 10-50 100-200 200÷2000 400÷3000
Speed of the mill rpm 3000÷5000 2000÷4000 1400÷2400 1000÷1800
Speed of the micro classifier rpm 1000÷4000 1000÷3000 500÷3000 400÷2500
Necessary filter mq 10÷20 40÷60 40÷100 100÷180
Noise level (1m) without noise insulation systems* db 95-100 95-100 95-100 95-100

*The noise level could change depending on the working conditions

The data and characteristics of this table are informative and subject to change without prior notice.