Rotary airlocks are installed on various machines for feeding and discharging bulk materials while preventing air from entering.

Simple versions are used as airlocks under cyclones or filters, while controllable versions are used for metered feeding and distributing of powdery materials.

Rotary airlocks designed as coarse feed valves are installed particularly in Polysius roller mill systems for feeding and reliable air exclusion. Due to their special design and heating capability, coarse feed valves can also reliably handle very large-sized and moist materials.