Compared with the single-stage pump, the difference is that the multi-stage pump has more than two impellers, which can absorb water and press water in multiple stages in stages, so that the water can be raised to a high position, and the lift can be increased or decreased as needed. The number of stages of the pump impeller.
Multi-stage pumps are mainly used for mine drainage, urban and factory water supply, and few for agricultural irrigation. They are only suitable for high-lift, low-flow high mountain water to solve the difficulty of drinking water for humans and animals.
The multi-stage pump has two types: vertical and horizontal.
The main models are D-type and DL multi-stage centrifugal pumps, and DW and DWL small multi-stage centrifugal pumps.
(1) D-type multi-stage pump performance range flow rate 6.3 ~ 720 cubic meters / hour, lift 16 ~ 600 meters, inlet diameter: 50, 75, 100, 125, 150, 200 mm, of which 50 ~ 125 mm pump type The high speed is 2950 rpm, and the 150-200 mm pump type speed is 1480 rpm.
(2) The structural type D multistage centrifugal pump is horizontal multi-stage (2~12 grade), the impeller is single suction, and the pump body is segmented. When the first stage impeller is double suction, it is indicated by DS. When two speeds are specified at the same time, the low speed is indicated by DA, and the multistage centrifugal pump used for boiler feed water is indicated by DG.
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1. Single-stage pump refers to a pump with only one impeller. The maximum lift is only 125 meters.
2. Multi-stage pump refers to a pump with two or more impellers. It can absorb water and pressure in multiple stages. Therefore, the water can be raised to a high position, and the lift can increase or decrease the number of stages of the pump impeller according to the need; the multi-stage pump can be matched by increasing the number of impellers in the case where the single-stage pump head needs to be equipped with two-stage motors. The use of four-stage motor can improve the service life of the pump and reduce the noise of the unit.
3. When the pump actually needs less than 125 meters, it can be based on the pump room area and pump price (multi-stage pumps are generally higher than single-stage pumps). The factors such as single-stage pump or multi-stage pump are considered comprehensively.
