Centrifugal pump components include which of the following?

• A. Diaphragm and Piston
• B. Volute and Impeller
• C. Shaft and Bearing
• D. Valve and Seat

Answer: (B)

In a centrifugal pump, the essential parts that actually move and shape the flowing fluid are the impeller and the volute. The impeller is the rotating element with blades that transfers energy to the liquid, increasing its velocity and pressure. The volute is the spiral housing that collects that high-velocity fluid and converts much of the velocity into usable pressure while directing the flow toward the discharge.

The other options describe components not defining for a centrifugal pump: a diaphragm and piston are typical of positive-displacement pumps, not centrifugal ones. A shaft and bearing are important supporting elements to allow the impeller to spin smoothly, but they aren’t the primary flow-modifying components. Valve and seat are flow-control elements in piping, not inherent pump components.