Centrifugal pumps or circular pumps are widely used in the operation of transferring liquids or gas. It is a device that uses a rotating impeller to increase the pressure of fluids. The centrifugal pump motion is related to the centripetal force, which is an outward force due to the inertial force acting on the object. The centrifugal pumps consists of the pump body, the impeller, the shaft, the shell and the bearing. The material of the centrifugal pump parts are usually aluminum alloy, cast iron, stainless steel, etc.
Centrifugal pumps have several advantages. Firstly, it can delivery high-volume output, it performance is proportional to the volume of the fluid passing through the pump; secondly, it can delivery different pressure; and finally, its mechanical structure is simple, and its installation is convenient.
When selecting a centrifugal pump, there are some standards that need to be considered. The first is the suction lift. A sufficiently deep sump or otherwise arranged suction viaduct must be available to achieve effective suction lift of the pump. Secondly, the pump efficiency needs to be considered. A good centrifugal pump should have a high efficiency, low noise and less wear. Thirdly, the maximum flow rate needs to be considered. The maximum flow rate is proportional to the size of the impeller. The larger the inside diameter of the impeller, the larger the flow rate.
More importantly, the maximum pressure should also be considered. The maximum pressure that the centrifugal pump can withstand depends on its safety margin. The safety margin of centrifugal pump is usually 1.05~1.1 times of its rated operating pressure. Finally, the pump seal needs to be taken into consideration. According to the working environment, wide varieties of pump seals are available, such as V-ring seals, lip seals, mechanical seals and packed seals, etc.
In addition, centrifugal pumps have performance characteristics that need to be taken into consideration when selecting them. These related performance characteristics include pump head, flow rate, power, efficiency, cavitation, and NPSHR (Net Positive Suction Head Required). These should be precisely determined before selecting a centrifugal pump.
In general, centrifugal pumps are used widely due to their good performance and many advantages. In order to choose the right one when selecting a centrifugal pump, we need to take the standards, performance characteristics and other factors into consideration. Furthermore, the selection process should take into account the working environment and the specific requirements of the project. Hence, by following the above mentioned guidelines, we can make the right decision.
