TABLE OF CONTENTS The water systems of this book embrace almost all types of pumps that are manufactured. The two broad classes of water pumps are centrifugal and positive displacement. Centrifugal pumps use centrifugal force while positive displacement pumps use some type of mechanical device to force water through the pump and water system. Generally, higher-capacity pumps are of the centrifugal type while smaller pumps can be centrifugal or positive displacement. The centrifugal pump will be discussed first, as it is the type used in all of these water industries for most pump applications. Positive displacement pumps are used for chemical feed and for sludges with higher viscosities; they will be discussed in Chap. 7. An exception to these classifications is the Archimedes screw type pump for large capacities at very low static heads. Such pumps are used for lifting water over an elevation such as a lift station or a riverbank and to an open flume, tank, or reservoir. They are a positive displacement type pump and will also be described in Chap. 7.
All pumps have some type of a rotating or reciprocating member that causes pressure on the water inside the pump. That water is then directed to an opening in the pump body or casing that allows the water to flow from...
