ML Grit Classifier

An effective classifier of the screw type which is manufactured in five standard sizes and is used for automatic removal of grit from grit traps or other sedimented particles with relative high sedimentation velocity.

The design is made of stainless steel and is completely enclosed.

Sand Classifier consists of a steel tank for the separation of grit with a special inclined screw conveyor for hoisting and dewatering of the sand. The mixture of grit and water is pumped from the grit trap to the inlet of the separation tank. A damping plate controls the water flow through the tank.

The tank becomes narrower at the outlet of the reject which is made by a transversed flume. The outlet of the reject is overly designed and also serves as an overflow pipe. The slope of the side plates of the tank sides and rear are adjusted to minimize the risk of bridging. The plate tank is generally dimensioned according to the theory of surface load for separation of grit grains with a diameter larger than 0.15 mm.

The Shaftless Screw

The conveyor spiral is manufactured in strong flat bars of steel. The steel is cold-rolled which gives a sharp increase in hardness and increased wear resistance. Absence of the shaft means that the spiral is flexible and can be placed directly in the U-trough without support bearings or shaft bushings. The shaftless screw also has a very good draining effect by letting the return water easily pass through where a shaft should have prevented this. In other words, an ideal solution for handling abrasive materials.


The conveyor spiral is mounted directly in a well-dimensioned driving unit. Speed is designed in order to provide good dewatering and sufficient capacity also for greater amounts of grit.


The conveyor trough is provided with a bolted cover. The trough is internally fitted with replaceable and very resistable hardened flat bars of steel serving as wear rails.


Control cabinet is not included as standard but to increase the life time of the screw and the lining it is recommended to use time control of the conveyor’s driving unit.

Benefits of the ML Grit Classifier

  • Available in five different sizes with capacity up to 180 m3 / h
  • High reliability and durability
  • Low maintenance with few wear parts
  • Good references with excellent operating experience
  • Low operating costs