Why is it critical to maintain pump shaft rotation speed below 2000 RPM?

Maintaining pump shaft rotation speed below 2000 RPM is crucial primarily to avoid cavitation damage. Cavitation occurs when the pressure in a liquid drops below its vapor pressure, leading to the formation of vapor bubbles. These bubbles can implode violently when they move to areas of higher pressure, causing significant damage to pump components such as the impeller and casing.

Operating at speeds that are too high can exacerbate this issue, as higher velocity can result in lower pressure areas within the pump, promoting cavitation. Preventing cavitation helps ensure the longevity and reliability of the pump, as well as efficient operation by maintaining proper flow and pressure characteristics.

In contrast, while operating efficiency, preventing overheating, and ensuring adequate fluid viscosity are important considerations in pump operation, they are less directly related to the critical speed threshold of 2000 RPM when evaluating cavitation risks specifically.