A water pump is a machine that delivers or pressurizes a liquid.
  It transfers the mechanical energy of the prime mover or other external energy to the liquid, increasing the energy of the liquid, mainly for transporting liquids including water, oil, acid and alkali, emulsion, suspoemulsion and liquid metal.
  Liquids, gas mixtures, and liquids containing suspended solids can also be delivered. The technical parameters of the pump performance include flow, suction stroke, lift, shaft power, water power, efficiency, etc.; according to different working principles, it can be divided into volume pump, vane pump and other types. The volumetric pump uses its change in the volume of the working chamber to transfer energy. The vane pump uses the interaction of the rotating blades and water to transfer energy. There are centrifugal pump,  axial flow pump and mixed flow pump. Below we mainly focus on the application of water supply pumps, centrifugal pumps and submersible pumps.