The casing surrounding a pump impeller that collects the water discharged by the impeller is called a __________.

The casing surrounding a pump impeller that collects the water discharged by the impeller is called a __________.

• A. Diffuser
• B. Casing
• C. Volute
• D. Impeller

Answer: (C)

The volute. In a centrifugal pump, the water is pushed outward by the impeller into a surrounding discharge housing that is shaped to collect the flow and guide it toward the outlet, while also slowing the flow to convert velocity into pressure. That expanding, spiral-like chamber is the volute. A diffuser serves a related purpose of slowing flow with vanes but is a different discharge path, and the impeller is the rotating part itself, not the discharge casing.

The volute. In a centrifugal pump, the water is pushed outward by the impeller into a surrounding discharge housing that is shaped to collect the flow and guide it toward the outlet, while also slowing the flow to convert velocity into pressure. That expanding, spiral-like chamber is the volute. A diffuser serves a related purpose of slowing flow with vanes but is a different discharge path, and the impeller is the rotating part itself, not the discharge casing.