What are the usual symptoms of cavitation in a centrifugal pump?

Cavitation in a centrifugal pump occurs when the pressure within the pump falls below the vapor pressure of the liquid being pumped, causing the formation of vapor bubbles. When these bubbles travel through the pump and reach areas of higher pressure, they collapse violently, leading to significant noise and vibrations. These sounds can often be described as a "gravel" or "marbles" noise, which is indicative of the turbulent collapse of the bubbles.

The presence of vibrations is also crucial to recognize because they result from the sudden changes in pressure when the bubbles collapse. Together, the noise and vibration are clear indicators of cavitation occurring within the system. Addressing cavitation early is critical, as prolonged operation under these conditions can lead to damage to the pump components, including erosion of the impeller and casing.

While high temperatures and corrosion, reduced flow rate and leakage, as well as increased pressure and temperature can occur due to other conditions or issues in the pump system, they are not primary indicators of cavitation. The defining symptoms specifically tied to the phenomenon of cavitation are the noise and vibration, making them the most accurate signs to look for in evaluating pump performance.