Before the pump is opened, the suction pipe and the pump must be filled with liquid. After the pump is opened, the impeller rotates at high speed. The liquid moves along with the blades. Under the action of centrifugal force, the impeller flies outward, and the liquid ejected slowly slows down in the diffuser of the pump housing, and the pressure gradually increases. Then it flows out from the pump outlet and the discharge pipe. At this time, in the leaves at the center of the vacuum area of low pressure liquid was thrown to the surrounding formation there is no air and no liquid, liquid pool at the surface of the liquid under the action of atmospheric pressure, through the suction pipe into the pump, the liquid is continuously pumped up from the liquid pool is also continuously from the outflow discharge tube. The basic parameters of the submersible pump include flow, lift, pump speed, matching power, rated current, efficiency, outlet pipe diameter and so on.