ABSTRACT
In this chapter we will discuss centrifugal pumps used in liquid pipelines. Although other types of pumps such as rotary pumps and piston pumps are sometimes used, the majority of pipelines today are operated with singleand multi-stage centrifugal pumps. We will cover the basic design of centrifugal pumps, their performance characteristics and how the performance may be modified by changing pump impeller speeds and trimming impellers. We introduce Affinity Laws for centrifugal pumps, the importance of net positive suction head (NPSH) and how to calculate horsepower requirements when pumping different liquids. Also covered is the pump performance correction for high-viscosity liquids using the Hydraulic Institute chart. We will also illustrate how the performance of two or more pumps in series or parallel configuration can be determined and how to estimate the operating point for a pipeline by using the system head curve.
