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

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Specific Spe<strong>ed</strong> <strong>and</strong> Modeling Laws 25<br />

Table 2-7<br />

Tabulat<strong>ed</strong> Performance at 3,550 RPM<br />

GPM<br />

0<br />

100<br />

200<br />

300<br />

400<br />

500<br />

600<br />

650<br />

H(ft)<br />

350<br />

349<br />

345<br />

337<br />

325<br />

300<br />

260<br />

235<br />

Eff. %<br />

0<br />

28<br />

48<br />

52<br />

70<br />

74<br />

73<br />

72<br />

GPM<br />

0<br />

150<br />

300<br />

450<br />

600<br />

750<br />

900<br />

975<br />

Table 2-8<br />

Tabulat<strong>ed</strong> Performance at 5,000 RPM<br />

H(ft)<br />

700<br />

698<br />

690<br />

674<br />

650<br />

600<br />

520<br />

470<br />

Eff. %<br />

0<br />

28<br />

48<br />

52<br />

70<br />

74<br />

73<br />

72<br />

bhp<br />

91<br />

94.4<br />

109<br />

142<br />

140<br />

153<br />

161<br />

160<br />

For complete performance conversion, see Tables 2-7 <strong>and</strong> 2-8. The hydraulic<br />

performance of the new 4-in. x 6-in. x 9-in. pump operating at<br />

5,000 RPM is shown in Figure 2-8.<br />

Conclusion<br />

There is no question that specific spe<strong>ed</strong> is the prime parameter for<br />

evaluating design of centrifugal pumps, evaluating pump selections, <strong>and</strong><br />

pr<strong>ed</strong>icting possible field problems. It is obvious, however, that no single<br />

parameter can relate to all aspects of final pump design. Different pump<br />

specifications covering a wide variety of applications force the designer<br />

to consider additional factors that may have an unfavorable effect on<br />

pump hydraulic performance. Pr<strong>ed</strong>ict<strong>ed</strong> performance can be affect<strong>ed</strong> by<br />

any of the following:

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