Pumps/pumping friction loss reduction

Example 6-1 Friction Loss in Drag-Reducing Solutions. Determine the percentage reduction in the power required to pump water through a 3 in. ID smooth pipe at 300 gpm by adding lOOwppm of degraded Separan AP-30. 

Lack of available NPSH may also be caused by high frictional loss in the suction piping. If this is the case, a small reduction in flow will not noticeably increase the pressure at the suction of the pump. A properly designed suction line to a centrifugal pump should have a frictional head loss of only a few feet of liquid. However, having a large-diameter suction line, and a relatively small draw-off nozzle, usually will lead to excessive loss of available NPSH. 

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