EN – 6
Operating principle
of the rotary vane pump
The pumping cycle is
given below:
Inlet
Transfer
Compression
Exhaust
This is a volumetric pump, with a functional part composed of:
• A hollow cylindrical stator with inlet and exhaust valves.
• A rotor mounted eccentrically inside the stator for pumping.
• Two vanes sliding in the rotor, forced against the stator by centrifugal force and
springs.
Single-stage
rotary vane pump
As the vane passes in front of the inlet
orifice, an increasing space is formed into
which the gas from the chamber to be
evacuated expands.
When the second vane passes, the space is
closed.
The gas trapped in the space between the
two vanes is transferred to the exhaust
orifice as the rotor rotates.
The space communicates with the exhaust.
which is fitted with a valve: the gas is
compressed until the safety valve is opened.
The gas is expelled into the oil casing when
the pressure is sufficient to open the valve.
In. Exh.
In. Exh.
In. Exh.
In. Exh.
