Centrifugal pumps rely on the role of the rotating impeller of the liquid to the mechanical energy of the original machine can be transferred to the liquid. Due to the effect of the liquid from the impeller inlet flow of exports, the velocity and pressure could have been increased by the impeller discharge liquid after extruding chamber. Most of the speed can be converted into pressure energy, then along the discharge pipe conveying out, at this time, at the inlet of the impeller for the expulsion of the liquid formed vacuum or pressure, inhalation of the liquid in the liquid pool in the role of liquid surface pressure (atmospheric pressure), is pressed into the impeller inlet, so the rotating impeller continuous continuous inhalation and discharged liquid.
Centrifugal pump has the advantages of simple structure, no pulsation of transfusion, simple flow regulation and so on, so it should be used as far as possible:
1. Measurement requirements, the use of metering pump.
2. Lift requirements are very high, flow is very small and no suitable small flow high lift centrifugal pump can be optional, optional reciprocating pump, such as cavitation requirements are not high, but also can use the vortex pump.
3. Head is very low, the flow is very large, can use the axial flow pump and mixed flow pump.
4. Medium viscosity is larger (> 650 ~ 1000mm2/s), can consider the selection of rotor pumps, such as: screw pump or reciprocating pump; viscosity is particularly large, can choose a special design of high viscosity screw pump and high viscosity reciprocating pump.
5. Medium gas content > 5%, flow is smaller and the viscosity is less than 37.4mm2/s, can use the vortex pump. If the flow rate is fluctuating, the reciprocating pump can be used.
6. To start frequent or irrigation pump disadvantageous situations should be used with self suction performance of pump, such as: self suction centrifugal pump, self priming vortex pump, self suction pump volume.
