Working principle of Dry Rotary Vane Vacuum Pump Oil-free dry rotary vane vacuum pumps are similar to other rotary vane pumps. Their simple construction and single-shaft direct drive make them a powerful, long-life rotary vane pump with low operating and maintenance costs. ​ Volume reduction and pressure increase are the principles of rotary vane operation. Oil-free rotary vane vacuum pump is a variable displacement pump. There is an eccentrically designed rotor in the cylindrical cavity with vane slots on it. The rotary vane slides out of the groove as the rotor moves, dividing the cavity into several separate working chambers. There is no metal contact inside the rotary vane pump, so wear is low. ​ Compared with other types of vacuum pumps, they have lower maintenance requirements and can maintain excellent performance for a longer period of time. Oil-free rotary vane vacuum pumps are the best choice for coarse/medium vacuum applications. Dry Rotary Vane Vacuum pump have 60-200m3 and 250-360m3.