2. The liquid level is too low, and air is inhaled.
3. The design of the inlet pipe is unreasonable, and the highest point is higher than the impeller (only refers to water absorption).
4. The installation method is unreasonable. In some places, the atmospheric pressure is low, and the selected pump has a large cavitation margin, or the pipe diameter is too small and the resistance is large, so only water absorption is needed for irrigation.
5. The gasification pressure of liquid increases.
6. Wrong choice, the pump seriously deviates from the best working point.
7. Eliminate air exhaust in the pipeline and pump body caused by damaged air valve, incomplete air exhaust or other reasons.
Specific reasons: the cavitation of water pump is caused by the vaporization of water. The so-called vaporization is the process of water changing from liquid to gas. The vaporization of water is related to temperature and pressure. At a certain pressure, when the temperature rises to a certain value, water begins to vaporize. If the pressure drops to a certain value at a certain temperature, water will vaporize, and this pressure is called the vaporization pressure of water at this temperature. If the pressure in the local area is equal to or lower than the vaporization pressure corresponding to the water temperature during the flow, water will vaporize there. After vaporization occurs, many small bubbles mixed with steam and gas will be formed. When the bubbles flow from the low pressure area to the high pressure area with the water flow, the bubbles burst under the action of high pressure, and the high pressure water flows to the space occupied by these original bubbles at a very high speed, forming an impact force. Under the action of surge pressure, the metal surface is fatigued and seriously damaged. Therefore, we call the whole process of bubble formation, development, rupture and material destruction cavitation.