ABSTRACT
Screening is an operation used for the separation of particles according to their sizes. Screening is generally used for dry treatment of coarse material. Dry screening can be done down to 10 mesh with reasonable efficiency. Wet screening is usually applied to materials from 10 mesh down to 30 mesh but recent developments in the Sieve Bend Screen have made the wet screening possible at the 50 micron size. Screening is effected by continuously presenting the material to be sized to the screen surface which provides a relative motion with respect to the feed. In the mineral industry, screens are rarely used for separations below 0.2 mm because they have inadequate capacity. A number of factors determine the rate at which particles pass through a screen surface and they can be divided into two groups: those related to particle properties and those dependent on the machine and its operation.
