ABSTRACT
A metering pump is a positive displacement pump providing a predictable and accurate rate of process fluid flow. Normally the application-design, specification, and use of pumps are the concern of mechanical engineers and machinery designers. Metering pumps, however, are sometimes used to actually measure or control flow rate, and in many cases they are the final control elements in an instrumentation loop. The three basic metering pump designs are the peristaltic, piston, and diaphragm types. They are all positive displacement devices used for the precise charging of corrosive, radioactive, toxic, flammable, or otherwise difficult fluids such as slurries, melts, liquified gases, or liquid metals. Peristaltic action is similar to the operation of the intestines and other hollow muscular structures, where the successive contraction of the muscular fibers of their walls forces their content forward.
