Centrifugal Pump Performance Curves

Pump performance for different liquids, in this case sea water vs water.  Normally pump manufacturers supply data for water using a specific gravity (SG) of 1.0 (density of 1000 kg/m3). If the manufacturers curve was made using a SG of 1.021 the volumetric flow delivered by the pump (assuming it centrifugal) won’t change if the fluid density changes. The power requirement only will increase as a function of density. Usually a manufacturer has a tolerance of up to (+/- 5%) on the published performance curve. Viscosity and density do not affect flow v's head curve (unless viscosity is high) only power requirement. So within the accuracy of the flow calculations, manufacturer’s tolerances and temperatures changes likely to be experienced, it is not necessary to make any changes to the supplied pump data.