The difference between vertical multistage pump and single stage pump is introduced

The first is to see the number of impeller

I. single-stage pump: there is only one impeller in the pump. At normal speed, the maximum lift range of single-stage pump can reach 1 ~ 1.5mpa.

2. Vertical multistage pump: there are 2 or more impeller in the pump.

The liquid flows through each impeller successively, one impeller is a stage. The more series, the higher the head. The stage of multi - stage centrifugal pump is generally between 2-13 stage, more installation and operation are inconvenient. Now with the development of the mechanical industry, multistage centrifugal pump is moving towards high

Speed less progression direction. At present, the high pressure centrifugal pump manufactured abroad, the speed up to 7000 RPM above, its level is only 2-3.



Second needs to see the multistage pump and single stage pump head classification

1. Single-stage pump: head less than 0.2mpa (20m water column);

2. Medium pressure pump: single-stage head is 0.2 ~ 1MPa(20 ~ 102 m water column);

3. Vertical multi-stage pump: single lift is higher than IMPa(more than 102 meters water column);

The single-stage head value of a vertical multistage pump is equal to the total head value of the pump divided by the series.

According to the single head value to distinguish the pump is low pressure pump, medium pressure pump or high pressure pump, this is not consistent with the high and low pressure pump according to the total head value. If from the conventional view, the multi-stage pump belongs to the high-pressure pump, but according to the single-stage head classification, the multi-stage pump is not necessarily high pressure

Pump. For example, 100D45×8 centrifugal pump has 8 stages and the total head is 3.6mpa (367m water column), but its single stage head is only 0.45mpa (46m water column), which is still a low-pressure pump. Only the vertical multi-stage pump with high speed and small level can be considered as a real multi-stage pump because of its high single-stage head.

Such as:

1. Vertical multistage pump: multiple impeller.

2. Single-stage pump: only one impeller.

Classified by diversion pattern

1. Volute pump: the radial section of the pump body is like the shape of snail shell, most single-stage pumps are in this form.

Guide vane pump: there are several fixed guide vanes installed in the impeller periphery, most vertical multistage pumps belong to this form.