Cavitation:
Because the suction pump is to rely on the pressure of the air into the water pump, so the water pump at the entrance of the pressure below the atmospheric pressure. However, the inlet pressure of the pump can not be less than the saturation vapor pressure at that time, otherwise, the water will produce vaporization, dissolved gas in the water will escape, the formation of steam and escape gas mixture of small bubbles. These bubbles into the impeller, with the increase of pressure, vaporization of the water vapor condenses into water, volume sharply reduced, the formation of partial vacuum, the surrounding water to vacuum produced great impact, and continue to function in the impeller, the impeller produces fatigue, and to make the surface of metal loss; at the same time, from the water from escaping the vividness of the gas with the help of water condensation heat release and the metal produce chemical corrosion, so that the impeller soon honeycomb pits, and gradually formed a hollow, and this phenomenon is known as cavitation phenomenon.
Pump cavitation, vibration and noise, flow, head, power and efficiency decreased significantly, serious will appear to flow. Therefore, the pump can not be carried out in the case of cavitation. Pump head down 1%, as the occurrence of cavitation.
The influence factors of the cavitation of centrifugal pump mainly include the water absorption height of water pump, the resistance of water suction pipe, the flow rate and the air pressure of the installation place of the pump and the working water temperature. Water pump installation location of the atmospheric pressure is usually the same, resistance, flow rate, temperature change is not large, so the water pump does not occur cavitation is the primary factor of water absorption. Correctly determine the maximum water absorption of the pump, the installation of the pump and ensure its normal safety operation is of great significance. The calculation method of water absorption height of pump is introduced.
Water absorption height
