The   Vickers Vane Pump   states that the balanced vane pump is a very versatile design. The rotor and blades are contained within a double eccentric cam ring with two inlet segments and two outlet segments per rotation. This double pumping action not only provides a compact design, but also brings another important advantage: although the pressure acting on the rotor in the outlet region is high, the forces at the two outlet regions are equal and opposite. , completely offset each other.