1. Single-stage pump refers to a pump with only one impeller, the maximum lift is only 120 meters;

2. Immersion multi-stage hot oil pump refers to a pump with two or more impellers, the maximum lift can exceed 120 meters; immersed multi-stage hot oil pump can be equipped with two-stage motor in the single-stage pump lift By increasing the number of impellers to match the four-stage motor, pump life and unit noise can be improved, but immersing multi-stage hot oil pump repairs is a bit more difficult than single-stage pumps.

When the actual pump head needs to be less than 120 meters, it can be based on the pump room area and pump price (the multi-stage hot oil pump is generally higher than the single-stage pump), and other factors such as single-stage pump or immersion in multi-stage heat. Oil pump.

With the advancement of technology, the pump of the single-stage impeller can increase the lift of the pump by increasing the speed of the pump, instead of immersing the multi-stage hot oil pump, it is only expensive.