Rotary Feeder A rotary feeder, also known as a rotary airlock valve or rotary valve, is a mechanical device used to regulate the flow of bulk materials from hoppers, silos, or bins into conveying systems while maintaining an airlock or pressure seal. It consists of a housing with an internal rotor that has multiple vanes forming pockets. As the rotor turns, material is trapped in the pockets at the inlet and then discharged at the outlet, ensuring controlled feeding. Rotary feeders are commonly