Rotary flow control valve and rotary shut-off valve are designed for use in all industrial areas in which powdery bulk materials are processed, conveyed, stored, distributed, weighed or metered. The rotary flow control valve is responsible for precise and continuous adjustment of the bulk material flow from bins and silos. The rotary shut-off valve is used where quick and reliable shut-off is necessary. The two valves are suitable for material flows from 10 to 1000 m³/h.