What is a Suction Lift Pump Configuration?
In a suction lift configuration a centrifugal pump takes suction from a source of liquid located below the pump centerline.
All centrifugal pumps must be primed prior to operation. They cannot be run dry. However, once a pump and the suction piping leading to the pump are primed in many cases it is possible for the pump to lift liquid from a point below the pump as it operates. A pump layout in which the source of liquid is below the pump is called a suction lift configuration.
Self-priming pumps are commonly used in suction-lift configurations. Self-priming pumps are designed with a large reservoir that remains full even when the pump is not in operation. When the pump begins to operate, air is drawn out of the suction piping and pushed out of the discharge. Once all air has been drawn out of the suction piping the pump begins to produce flow. It’s important to note that even self-priming pumps cannot run dry but must have their casing filled with water prior to operation.
Standard centrifugal pumps can also be applied in a suction lift configuration, but in order to do so, a priming mechanism must be used to evacuate air out of the suction piping and pump casing prior to energizing the pumps.