OVERVIEW

Pumping of liquids is almost universal in chemical and petrochemical processes. The many different materials being processed require close attention to selection of materials of construction of the various pump parts, shaft sealing, and the hydraulics of the individual problems. A wide variety of pumps types have been developed to satisfy the many special conditions found in chemical plant systems; however, since all of these cannot be discussed here, the omission of some does not mean that they may not be suitable for a service. In general, the final pump selection and performance details are recommended by the manufacturers to meet the conditions specified by the process design engineer. It is important that the designer of the process system be completely familiar with the action of each pump offered for a service in order that such items as control instruments and valves may be properly evaluated in the full knowledge of the system.

This chapter presents information on rating, sizing, and specifying process pumps. The emphasis will be on centrifugal pumps, which are by far the most widely used in the process industries; however, applications of other types of pumps will also be discussed (Table 5-1). The chapter further provides the Excel spreadsheets for rating/sizing a centrifugal pump (Figure 5-61b), and to determine pump efficiency, hydraulic brake horsepower, and actual brake horsepower for pumps at varying flow rate and developed head.

Table 5-1: General Types or Classification of Pumps

Centrifugal	Rotary	Reciprocating
Centrifugal	Cam	Piston
Propeller	Screw	Plunger
Mixed...