Which centrifugal pump component rotates to create centrifugal force that acts on the fluid?

The impeller is the key component in a centrifugal pump responsible for rotating and creating the centrifugal force that acts on the fluid. When the impeller spins, it imparts kinetic energy to the fluid, which causes it to move outward from the center of the pump towards the discharge. This action generates the necessary pressure to push the fluid through the pump and into the piping system.

In contrast, the volute is a casing component designed to collect the fluid that has been accelerated by the impeller and convert its kinetic energy into pressure. The diffuser, located downstream of the impeller, aids in further converting kinetic energy into pressure by gradually slowing down the fluid flow. The motor provides the mechanical energy required to rotate the impeller but does not directly interact with the fluid. Thus, while all these components play essential roles in the overall functioning of a centrifugal pump, it is the impeller that is directly responsible for the centrifugal force and fluid movement.