To prevent cavitation, the NPSH available must be what in relation to the NPSH required?

To effectively prevent cavitation in pumping systems, the Net Positive Suction Head (NPSH) available must be greater than the NPSH required by the pump. This ensures that there is sufficient pressure at the pump's suction inlet to prevent the formation of vapor bubbles, which occur when the local pressure drops below the liquid's vapor pressure.

In practical terms, having the NPSH available at 10% or more than the NPSH required provides a safety margin. This margin accommodates variations in fluid temperature, changes in elevation, and other operational factors that might affect the net positive suction head. Ensuring the NPSH available is significantly higher, such as 10% more, enhances the reliability and efficiency of the pump system, reducing the risk of cavitation.

A common issue with insufficient NPSH available is pump damage and reduced performance due to cavitation, which can lead to increased maintenance costs and potential system failures. Therefore, maintaining this margin is critical for the longevity and proper operation of pumping equipment.