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Centrifugal Pumps Design and Application 2nd ed - Val S. Lobanoff, Robert R. Ross (Butterworth-Heinemann, 1992)

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1<br />

Introduction<br />

System Analysis for Pump Selection<br />

Before a pump can be select<strong>ed</strong> or a prototype design<strong>ed</strong>, the application<br />

must be clearly defin<strong>ed</strong>. Whether a simple recirculation line or a complex<br />

pipeline is ne<strong>ed</strong><strong>ed</strong>, the common requirement of all applications is to<br />

move liquid from one point to another. As pump requirements must<br />

match system characteristics, analysis of the overall system is necessary<br />

to establish pump conditions. This is the responsibility of the user <strong>and</strong><br />

includes review of system configuration, changes in elevation, pressure<br />

supply to the pump, <strong>and</strong> pressure requir<strong>ed</strong> at the terminal. Relevant information<br />

from this analysis is pass<strong>ed</strong> on to the pump manufacturer in the<br />

form of a pump data sheet <strong>and</strong> specification. From the information given,<br />

the following will ultimately determine pump selection.<br />

• Capacity range of liquid to be mov<strong>ed</strong><br />

• Differential head requir<strong>ed</strong><br />

• NPSHA<br />

• Shape of head capacity curve<br />

• Pump spe<strong>ed</strong><br />

• Liquid characteristics<br />

• Construction<br />

Differential Head Requir<strong>ed</strong><br />

The head to be generat<strong>ed</strong> by the pump is determin<strong>ed</strong> from the system<br />

head curve. This is a graphical plot of the total static head <strong>and</strong> friction<br />

3

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