Although the centrifugal pump remains the workhorse of the process industry, positive displacement pumps have particular specialised benefits and are widely used in a variety of applications. PD pump designs are much more varied than centrifugals and use a whole range of pumping principles:—rotary lobe, peristaltic, progressive cavity and flexible impeller pumps, for example. Each of these have particular advantages, and the individual application should be considered carefully when making a choice. One general benefit shared by all three principles is a gentle pumping action which allows shear-sensitive fluids to be pumped with minimal damage. For this reason, these pump types are frequently considered for applications in the food, beverage, pharmaceutical and biotech industries. Pumps used in these industries, however, must be hygienic.
展开▼
