Circular Screeners are one of the most common types of machines produced for classification, sifting and separation of products  such as chemicals, pharmaceuticals, foods, minerals and other powders and granules. 

Circular vibrators typically utilise vibratory motions and concise of one or more horizontal screens mounted in round frames with ring clamps. When multiple screens are utilised the atonal decks are stacked so that the screen with the largest mesh openings is located at the top with the deck with the smallest mesh openings located at the bottom of the stack.

When used in operation the feed material is inserted into the top of the screener as an eccentric-weight drive mechanism applies horizontal and vertical vibrations to the screens promoting the flow of the material through the deck/s. The vibrations cause the material that fits through the mesh opening of that deck to drop through. Any particles that are unable to pass through the mesh openings travel across the screen to a discharge exit where they can be collected.