The PVA pumps are variable displacement vane pumps with piloted type hydraulic pressure compensator.
- They permit instantaneous adjustment of the flow rate according to the circuit requirements.The consequence is that energy consumption is reduced and adequate in every cycle phase.
- The pumping group is complete with hydrostatic axial compensation distribution plates that improve the volumetric efficiency and reduce wear of the components.
- The pressure compensator operates with the principle of keeping the cam ring of the pumping group in the eccentric position with use of a piston controlled hydraulically by a pressure pilot stage.
- When the delivery pressure equals the pressure corresponding to the pilot stage setting, the cam ring is moved toward the center adjusting the flow rate to the plant requirements.
- In zero flow demand conditions, the pump delivers oil only to compensate any possible bleedings and pilotings, keeping the circuit pressure constant.
- The compensator response times are very restrained and such as to allow elimination of the pressure relief valve.
- Also available are the versions with maximum flow adjustment PVA***Q and with the device for selection of two independent pressure values with solenoid valve PVA***M