Vane Pumps consists of a circular rotor offset in a circular cavity. Each vane in the rotor is forced inward by the housing walls as it approaches the pump discharge hole. Once past the discharge, the vane is forced outward by centrifugal force, hydraulic pressure or pushrods to press the vane against the housing, creating a tight seal so the vane can force liquid fluid through the pump.
Vane pumps are used in aviation, the auto industry, bulk transfer of LPG and NH3, carbonators for soft drink dispenser, and espresso coffee machines. They are also used for the pumping of solvents and aqueous solutions.