First, the pump impeller cavitation: pump impeller cavitation phenomenon troubled the normal operation of the pump a major problem, the most direct manifestation of pump impeller cavitation is the impeller damage to the pump impeller, seriously affecting the good performance of the pump, directly endangering the safety of production. Second, the process of cavitation pump: Pump in operation, if the over-flow part of the local area (usually impeller blades imported somewhere later), for some reason, the absolute pressure of pumping liquid down to the current temperature Of the vapor pressure, the liquid begins to vaporize there, forming bubbles. These bubbles flow forwards with the liquid, to a high pressure at the high pressure liquid around the bubble causes the bubble suddenly shrink and even rupture. In the bubble rupture at the same time, the liquid particles will fill holes at high speed, the collision occurred with each other to form a water hammer. This phenomenon occurs in the solid wall will make the flow of components by corrosion damage. This is the so-called pump cavitation cavitation phenomenon. Third, the serious consequences of pump cavitation: 1, resulting in noise and vibration. Cavitation cracks and high-speed impact bubbles can cause serious noise. In addition, the cavitation process itself is a process of repeated condensation, impact, accompanied by a great pulse force. If these pulsating frequencies are close to the natural frequencies of the equipment, they will cause strong vibrations. If the cavitation caused by the pump rotating parts material damage, will inevitably affect the rotor static balance and dynamic balance, leading to serious mechanical vibration. 2, so that the performance of centrifugal pumps. Pump cavitation, will make its performance decline. Pump less bubbles, the pump performance curve did not change significantly, which is the nascent stage of cavitation. Large bubbles, the runner is "blocked", then cavitation has reached the stage of development. Performance of the pump performance curve, there was a clear change in the performance curve decreased significantly, the emergence of the "fracture" condition. But different than the speed pump, the cavitation performance curve is different from the situation. 3, causing material damage. Cavitation occurs, due to mechanical erosion in the common role of chemical corrosion, the material is damaged. Due to the complexity of the cavitation phenomenon, its formation mechanism is still under study. Generally believed that mechanical impact caused by hydraulic erosion, the first to destroy the material, but also the main factor in the destruction of the material. Fourth, to prevent pump cavitation approach: a, the correct selection b, material effects c, to prevent excessive pressure rise d, water hammer eliminator device e, the installation of guide vane before five cavitation pump has occurred Solution: For a pump device that already produces cavitation, there is a serious need to replace a new impeller assembly with a slight intake of a small amount of air on the suction side to reduce the noise and vibration caused by cavitation.