Mechanical efficiency
Mechanical efficiency (ηm) is described as the ratio between the power input (P) minus the mechanical power loss (PL.m) and the power input itself:
Power loss refers primarily to the friction loss in pump bearings (e.g. plain and rolling element bearings) and shaft seals.
It typically consumes 0.5 to 2 % of power input, whereby this figure generally becomes smaller the more powerful the centrifugal pump.
