As we all know, the drainage pump is used to discharge the liquid in the sump or large liquid storage tank.
Its working principle is: relying on the high-speed rotating impeller, the liquid drainage pump obtains energy under the action of inertial centrifugal force to improve the pressure. Before the pump works, the pump body and water inlet pipe must be filled with water to prevent cavitation. When the impeller rotates rapidly, the blade promotes the water to rotate quickly. The rotating water flies away from the impeller under the action of the centrifugal mechanical diaphragm metering pump. After the water hydraulic diaphragm metering pump in the pump is thrown out, a vacuum area is formed in the center of the impeller. The water of the water source is pressed into the inlet pipe through the pipe network under the action of atmospheric pressure (or water pressure). In this way, continuous pumping can be realized. It is worth mentioning that before starting the centrifugal pump, the pump shell must be filled with water before starting, otherwise the pump body will be heated, vibrated, the water output will be reduced, the pump will be damaged (referred to as "cavitation") and equipment accidents will be caused! The so-called cavitation refers to the phenomenon that when the centrifugal pump is started, if there is air in the pump, due to the low density of the air and the small centrifugal force generated after rotation, the low pressure formed in the central area of the impeller is not enough to suck the liquid whose liquid level is lower than the pump inlet into the pump and cannot transport the fluid.
