Q6Basic Mechanical Engineering
Question
Q.6 What is priming in centrifugal pump?
Answer
Priming is the absolutely mandatory operational process of manually filling a centrifugal pump's entire volute casing and suction pipe completely with the working liquid strictly to displace all trapped air before activation.
A standard centrifugal pump physically generates pressure directly proportional to the absolute physical density of the fluid currently residing within its rotating impeller.
Because the density of atmospheric air is mathematically thousands of times lower than that of liquid water, an air-bound impeller structurally cannot ever generate sufficient pressure differential to overcome the static suction lift. Therefore, rigorous 'priming' (completely flooding the internal casing and suction lines with liquid) is strictly required to expel all trapped air, enabling the pump to successfully draw the heavier liquid.