The centrifugal pump relies on the high-speed rotation of the impeller, so that the liquid is thrown to the edge from the center of the impeller under the action of centrifugal force, and obtains kinetic energy and pressure energy. After the liquid enters the pump casing, the flow channel gradually expands, and part of the kinetic energy is converted into static pressure energy, which is finally discharged from the outlet. At the same time, the center of the impeller forms a low pressure area, and the external liquid is sucked in under the action of atmospheric pressure to form a continuous transmission.