BEP is where the pump is most efficient.
A practical pump will never be able to convert all its kinetic energy to pressure energy. Parts of the energy will always be internal or external lost.
- hydraulic loss - due to disk friction in the impeller, rapid change in flow directions and velocity changes throughout the pump
- volumetric loss - due to internal re-circulation caused by wear in rings and bushes
- mechanical loss - due to friction in seals and bearings
BEP - Best Efficiency Point
The maximum efficiency for a pump is normally in its "design point" - also called
- BEP - or the "Best Efficiency Point"
For pumps operating in all other positions - the efficiency will be less than in BEP.