What is cavitation in pumping systems?

• A. Cavitation is the formation and collapse of vapor bubbles that can damage equipment and reduce efficiency.
• B. Cavitation is a chemical reaction between minerals.
• C. Cavitation occurs only in non-pressurized systems.
• D. Cavitation improves pump reliability.

Answer: (A)

Cavitation happens when the pressure in the liquid at the pump suction drops below its vapor pressure, causing tiny vapor bubbles to form. As the liquid moves into higher-pressure regions near the impeller, these bubbles collapse violently, sending shock waves that can pit and erode metal surfaces, increase vibration, and reduce flow and efficiency. That combination of bubble formation and destructive collapse is why this description fits cavitation so well: it explains both the formation of void spaces and the damaging, efficiency-sapping collapse that follows. It isn’t a chemical reaction between minerals, it isn’t tied to non-pressurized systems, and it doesn’t improve reliability. Preventing cavitation involves ensuring adequate suction head (NPSH), managing temperature and flow, selecting the right pump, and venting gases to keep the liquid from vaporizing under the pump’s operating conditions.