Rotary airlock valves are also called rotary feeders, rotary valves, or just rotary airlocks. Used in both pressure style and vacuum style pneumatic conveying systems, these valves serve as a “lock” to prevent air loss while simultaneously performing vital material handling functions.
A Rotary Airlock Feeder separates a pressure differential while allowing material to pass through it. Best way of thinking of how it works is imaging a revolving door in a building; it allows material to pass through, but maintains the pressure differential between the building and outside.