1. Single-stage pump refers to a pump with only one impeller and a maximum lift of only 125 meters;
2. Multi-stage pump refers to a pump with two or more impellers, which can absorb water and pressurize water in stages and stages, so that the water can be raised to a high position, and the lift can increase or decrease the number of stages of impellers according to need; Multistage pump needs to be used in single-stage pump head. When two-stage motors are required, four-stage motors can be used by increasing the number of impellers, which can improve the service life of the pump and reduce the noise of the unit.
3. When the actual lift of the pump is less than 125 meters, the choice of single-stage pump or multi-stage pump can be considered comprehensively according to the pump room area, pump price (the price of multi-stage pump is generally higher than that of single-stage pump), and other factors.