As a self priming pump manufacturer, Borra tells everyone that the cause of cavitation in the self-priming pump is that the local pressure in the pump is lower than the saturated vapor pressure of the water, or that vaporization is a prerequisite for cavitation.
The causes of cavitation caused by self-priming pumps are roughly as follows:
1. The self-priming pump installation height is too high. As the installation height of the self-priming pump increases, the vacuum at the pump inlet increases, causing the pressure inside the pump to drop too low.
2. The actual working condition of the self-priming pump is far from the design working condition. When the pump is operated under non-design conditions, it is also possible to create a bottom-up band vortex (called a vortex band) under the impeller. When the vortex center pressure drops to a saturated vapor pressure, the vortex band becomes a cavitation zone. When the vortex extends into the pump, it not only promotes and aggravates the cavitation of certain parts of the pump, but also causes strong vibration of the unit and makes a roar.
3. The water inlet conditions of the self-priming pump are not good. For the pump with elbow inlet flow channel, the pressure distribution of the inlet of the pump impeller is not uniform due to the uneven distribution of the flow velocity of the curve. The vortex of the inlet tank will pre-spin the water entering the pump or bring the air into the impeller. The flow velocity and pressure distribution at the inlet are not uniform, which leads to the occurrence of steam pockets and cavitation. According to foreign cavitation test data, the greater the gas content in the water, the earlier the cavitation begins.
4. The altitude of the self-priming pump is higher when the altitude of the self-priming pump is higher. At high altitudes, the lower atmospheric pressure will cause the pump inlet pressure to be lower; the higher the water temperature, the greater the saturated vapor pressure and the easier the water will vaporize.
Through careful understanding of the causes of cavitation generated by the above self-priming pump, it is hoped that the user will pay attention to avoid the above-mentioned factors that may cause cavitation during the use of the self-priming pump. Ensure that the self-priming pump can operate stably and lastingly.