Let us now analyse an innovative type of sewage sludge pump, namely piston or piston/membrane pumps with a hydraulic system.
In this article we have seen how piston pumps are made from a constructional point of view for feeding filter presses or for transferring generally medium abrasive pressurised fluids.
On the other hand, in this other article we saw the same features, but for piston-diaphragm pumps for transferring viscous and abrasive fluids.
Now let us look more specifically at the advantages of using a hydraulically driven piston or piston-diaphragm pump.
You can have the maximum pressure value at all flow values of the pump, as with a normal volumetric machine.
Actually, this type of pump was born just like that, only the motion generation system was changed from mechanical to hydraulic.
This is because, especially in pumps of a certain capacity and economic importance, switching to a hydraulic power unit has brought major advantages.
In terms of efficiency, switching to a hydraulic solution resulted in better efficiencies and therefore lower installed power for the same performance.
In a hydraulic power unit, it is much easier to maintain high efficiencies over the years and it is also cost-effective to carry out maintenance.
In fact, by using a small hydraulic pump, which is responsible for generating the motion of the entire pump, the efficiency of the whole machine is very high.
If it were then to be overhauled, the economic impact would be limited.
Just imagine in a pump that has to give flow rates from 10 m^3/h upwards, what impact the maintenance of the gearbox unit with all its gears, bearings, pivots, shafts, connecting rods, etc. could have.
There is also a not insignificant advantage in terms of downtime.
In fact, with a pump of this type, it is possible to have a second hydraulic unit as a spare, which can be replaced immediately if maintenance is required.
I can simply decide to replace the hydraulic unit on which maintenance is to be carried out with a new one and start production again in no time; an advantage that is clearly not available when the main handling system is mechanical.