Selecting a sifter for scalping, removing fines, or grading
A sifter [also called a screener] is a unique and often misunderstood machine compared with other equipment in the powder and bulk solids handling industries: Only one material goes into a sifter, but two or more materials come out. This article takes the mystery out of the machine by discussing sifter uses, where to install a sifter, sifter types, and selection factors.
Any dry free-flowing material can be handled in a sifter, including pharmaceutical and cosmetic powders; wood chips and wood flour; minerals such as limestone, pumice, and silica; food products such as wheat flour, sugar, and baking soda; plastics and rubber; and pigments such as carbon black. The sifter mechanically separates the material according to individual particle size by moving the material in relation to a screen.