Given the variety of pumps that is evident from the foregoing system of classification, it is conceivable that an inexperienced person might well become somewhat bewildered in trying to determine the particular type to use in meeting most effectively the requirements for a given installation. Selecting and Purchasing Pumps guide that provides the reader with reasonable familiarity regarding the details that must be established by or on behalf of the user in order to assure an adequate match between system and pump.
None of these, however, provide a concise comparison between the various types, and Figure 1
FIGURE 1 Approximate upper limit of
pressure and capacity by pump class
has been included here to do just that, at least for the basic criteria of pressure and capacity. The lines plotted in Figure 1 for each of the three pump classes represent the upper limits of pressure and capacity currently available commercially throughout the world. At or close to the limits shown, only a few sources may be available, and pumps may well be specially engineered to meet performance requirements. At lower values of pressure and capacity, well within the envelopes of coverage, pumps may be available from dozens of sources as pre-engineered, or standard, products. Note also that reciprocating pumps run off the pressure scale, whereas centrifugals run off the capacity scale. For the former, some highly specialized units are obtainable at least up to 150,000 lb/in2 (10,350 bar) and perhaps slightly higher. For the latter, custom-engineered pumps would probably be available up to about 3,000,000 U.S. gal/min (680,000 m3/h), at least for pressures below 10 lb/in2 (0.69 bar).
FIGURE 1 Approximate upper limit of
pressure and capacity by pump class
has been included here to do just that, at least for the basic criteria of pressure and capacity. The lines plotted in Figure 1 for each of the three pump classes represent the upper limits of pressure and capacity currently available commercially throughout the world. At or close to the limits shown, only a few sources may be available, and pumps may well be specially engineered to meet performance requirements. At lower values of pressure and capacity, well within the envelopes of coverage, pumps may be available from dozens of sources as pre-engineered, or standard, products. Note also that reciprocating pumps run off the pressure scale, whereas centrifugals run off the capacity scale. For the former, some highly specialized units are obtainable at least up to 150,000 lb/in2 (10,350 bar) and perhaps slightly higher. For the latter, custom-engineered pumps would probably be available up to about 3,000,000 U.S. gal/min (680,000 m3/h), at least for pressures below 10 lb/in2 (0.69 bar).
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