DETERMINATION OF THE WORKING AREA OF THE EDGE SIEVE OF GRAIN CRUSHER WITH INCREASED SEPARATING SURFACE

Abstract

Hammer crushers are widely used for the destruction of grain in feed preparation. When they work in the grinding chamber, as a result of the rotor’s rotation, air flows arise that involve particles of crushed material and whole grains in motion, thereby creating an air-productive layer. These air flows are influenced by the shape and geometrical parameters of the blades, their location, rotor diameter and speed, and the parameters of the separating surface. Under the conditions of Knyagininskiy University, a hammer crusher with an enlarged separating surface was developed, the working chamber of which was formed by two end and one peripheral sieves. Angle hammers, straight hammers, or a combination of straight hammers and corner blades placed between them were installed on the rotor as working units. The study was carried out to study the effect of the type of working units and the area of overlapping of the edge sieve on the direction of air flows in the grinding chamber and to determine the working area of the edge sieve. Angle hammers are characterized by the movement of air flows in the axial direction and their following distribution: suction into the grinding chamber in the central part of the end sieve and ejection along the outer circumference of the sieve. Based on this, the entire area of the end sieve can be divided into three parts: the suction zone, the ejection zone and the transition zone. An increase in the length of the angular blades leads to an increase in the working area of the end screens, therefore, the use of combined working units is rational. Installation of working units in the form of straight hammers is impractical, since the working area of the end screens is minimal. It is also irrational to use working units in the form of angle hammers, since they are characterized by the maximum area of the retraction zone and a small working area of the end sieves