The setting principle of the outlet and inlet diameters of China effluent pump: generally, the outlet diameter is selected according to the economic flow rate, and the outlet diameter is determined in combination with the flow. When the pipe diameter is less than 250, it is 1 ~ 1.2m/s, and when the pipe diameter is 250 ~ 1000, it is 1.2 ~ 1.6 m / s. technically, the maximum speed of water flow should not exceed 2.5 ~ 3.0m/s, and the minimum speed should not be less than 0.6 m / S (to prevent deposition)
Small inlet flow rate, advantages(China effluent pump)
1. It is conducive to improving NPSHA of the device, and the pump is not easy to cavitation;
2. Little scouring to the pipeline, especially the medium containing particles;
3. It is not easy to generate static electricity;
4. The pressure drop of inlet filter is small;
5. In the same section, the medium flows evenly and the hydraulic loss is small.
Low inlet flow rate, disadvantage(China effluent pump)
1. Under the same flow rate, large pipe diameter is required and the pipeline cost is high;
2. For some easily precipitated media, the flow rate is too small, which is easy to cause deposition blockage;
3. The impeller inlet is large, the diameter of the ring is large, and the leakage is large.

The inlet of the pump is generally larger than the outlet diameter. Backstage whether the diameter of the inlet and outlet pipes of the centrifugal pump must be larger than that of the pump itself. This problem still needs to be analyzed in detail.
For most China effluent pump, the purpose of increasing the inlet and outlet pipe diameter is to reduce the flow rate of fluid in the pipeline, so as to reduce the pipeline resistance drop and finally reduce the power consumption of the pump, but increasing the pipe diameter is at the cost of increasing the pipeline investment cost. In this way, for the long-distance pipeline at the pump outlet, it can be considered to appropriately increase the pipe diameter to reduce the resistance drop, while for the short-distance pipeline, it can not be considered; As for the materials transported at the pump inlet that are liquefied gas, close to the boiling point, low suction position and other materials prone to cavitation, it should be considered to increase the pump inlet pipe diameter to reduce the resistance drop and avoid cavitation of the pump.




