# Affinity Law and Efficiency of a Pump Curve

1. Feb 26, 2017

1. The problem statement, all variables and given/known data
(Pump Curve given as attachment)

Find the point where the pump is delivering 1,200 gpm at 45 ft of head.
I.
What is the pump efficiency (read from the pump curve data)?
ii. What is the hp delivered to the water?
iii. What is the shaft hp required to drive the pump?

2. Relevant equations
ii.
HP = CFM * Inches of Water Column/6356 * Efficiency

3. The attempt at a solution
I.
I believe the efficiency is at 72.5% looking at the graph.
ii. 1200 * 30/6356 * .72 = 36,000/457,632 7.866 hp (I used 30 inches of water from the graph is that correct?)
iii. plot pump hp is 19hp, shaft hp=19/0.725=26.2 hp

#### Attached Files:

• ###### pump.png
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Last edited: Feb 26, 2017
2. Mar 3, 2017

### PF_Help_Bot

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