Pump Selection Quick Guide
Pump Selection Quick Guide
Pump Selection Quick Guide
Quick Guides
Pump Handbook - Igor J. Karassik, Joseph P. Messina, Paul Cooper, Charles C. Heald
GPSA Section 12
GPSA Section 12
GPSA Section 12
GPSA Section 12
GCAP Volume II
Example 1:
For a pump flow of 30 m3/h and pump head of 50 m, a single stage centrifugal pump would be
sufficient. Let make a checking, the specific speed and centrifugal pump efficiency is about 15 and
62%. The specific speed is more than minimum recommended of 10, single stage centrifugal pump
still consider acceptable although the pump efficiency is only average.
Example 2:
For a pump flow of 30 m3/h and pump head of 300 m, a multi-stage centrifugal pump would be
required. Lets check why not a single stage pump. The specific speed calculated is about 4 which is
far below 10. A single stage pump is not recommended. Assuming the pump head is equally split
between stage, 4 stages centrifugal pumps is required in order to meet specific speed more than 10.
With 4 stage centrifugal pump, the calculated specific speed is about 11 and pump efficiency is
about 57%. This 4 stage centrifugal pump configuration is acceptable.
Example 3:
For a pump flow of 10 m3/h and pump head of 300 m, a multi-stage centrifugal pump might be
considered. However...
With single stage pump, the specific speed and efficiency is about 2 and 10%.Obviously single stage
pump is not recommended with such low efficiency. Assuming the pump head is equally split
between stage, 8 stages centrifugal pumps would lead to specific speed of 11 and pump efficiency is
about 47%. With such a low efficiency and many stages of pump (high capital cost), one may
consider a reciprocating pump i.e. gear pump in this service.
Above only a quick selection method and checking criteria based on 2 factors i.e. specific speed and
pump efficiency, there may be other factor affecting the selection and will not be discussed here.
REFERENCE: http://webwormcpt.blogspot.com/2008/06/quick-pump-selection.html#google_vignette
Thanks for your attention