Where does cavitation damage primarily occur in a pump?

Cavitation damage in a pump primarily occurs at the outlet due to the high pressures and velocities involved during the fluid discharge process. When fluid moves through a pump, especially at the impeller, a drop in pressure can lead to the formation of vapor bubbles in areas where the pressure is low. These vapor bubbles are not stable and will collapse when they reach regions of higher pressure, often occurring around the impeller and the volute of the pump as the fluid exits.

When these vapor bubbles collapse, they produce shock waves that can cause significant damage to the metal surfaces, leading to pitting and erosion. While some might think damage could occur at the inlet or within other areas, the most severe impacts from cavitation occur as fluid is expelled from the pump under pressure. Recognizing this helps in designing pumps and operating them within the right parameters to prevent cavitation and its damaging effects.