The main feature of a Rotary Valve is to regulate the flow of material from one chamber to another while maintaining a good airlock condition. The material or product being handled is usually dry free flowing powder, dust or granules.
The granule type of product, especially if it is a plastic type, polythene or nylon etc., does not shear easily and consequently, without considerable care the standard drop-through type of valve leads to valve seizure and also considerable shock loadings.
To minimize these problems the Offset Airlock Valve ensures lower pocket fillage as its design means that the rotor is still being filled in the upward cycle with the pellets falling away at the shear point. Similarly, the pelican beak distributes the product across the full width of the rotor.