sludge pump on ship

BEP - the Best Efficiency Point of a Pump

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. 

Internal Losses

• 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

External Losses

• 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.