Special Designs: Self-Priming Pumps

Abstract

The standard centrifugal pump cannot handle air or vapors. Unless it is located beneath its source of supply, some means must be found of filling both the pump and its suction piping with liquid, that is, to prime it. A demand naturally developed, therefore, for a centrifugal pump able to handle appreciable quantities of air and to reprime itself automatically when located above the water supply. This requirement is especially important in the construction field because pumps may be used to dewater areas into which seepage is slower than the pump can handle. A standard pump will operate until it uncovers the entrance to the suction pipe, get air-bound, and then be unable to reprime itself even after sufficient seepage has accumulated to prevent further air infiltration.