The prime function of a rotary valve or airlock is to regulate the flow from one chamber to another while maintaining a good airlock condition. The product is mainly in dry powder or granular form.Airlocks are also important in the pneumatic conveying industry, where product is regulated into a pressure or vacuum conveying line while minimising air leakage.In the dust filtration field a good airlock is essential on cyclone and bag filter applications in order that the manufacturers quoted high dust collection efficiencies can be maintained.