Page 98 - Know and Understand Centrifugal Pumps
P. 98
Understanding Pump Curves
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Fiaure 7-4
The energy (BHp) curve
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Next, let's consider the energy curve, the brake horsepower (BHp),
required by the pump. This curve is probably the easiest to interpret
because it is practically a straight line. Consider the following: the pump
consumes a certain quantity of energy just to maintain shut-off head.
Then, as flow begins and increases, the horsepower consumption
normally increases. (On certain specific duty pumps, the BHp may
remain mostly flat or even fall with an increase in flow.) The BHp curve
is normally seen this way (Figure 7-5).
