The major advantage of compressed air-driven hydraulic pumps comes from the fact that they only function when their performance is really needed. This feature is commonly called ‘power on demand’ because such pumps slow down and stop cycling when the air pressure balances the oil pressure through the intensification ratio. For instance, when the actuator in the circuit is not moving, the pump is not cycling. When the directional control valve in the system opens the path from the pump to the actuator, the pump starts up automatically to provide the fluid flow needed to extend the actuator in its work. When the work is done, the directional valve blocks the pathway and the pump stops. It is as simple as that – power on demand! Just think how much energy is saved in a clamping application, a filter press, or a tire press where the pressure is sustained for minutes or hours with only system leakage to be made up.