A pump is a machine that delivers fluid or pressurizes fluid. It transfers the mechanical energy of the prime mover or other external energy to the liquid to increase the energy of the liquid. The pump is mainly used to transport liquids such as water, oil, acid-base liquid, emulsion, suspension emulsion and liquid metal, as well as liquid, gas mixture and liquid containing suspended solids. Pumps can usually be divided into three categories: positive displacement pumps, power pumps and other types of pumps according to their working principles.
In addition to the classification according to the working principle, it can also be classified and named according to other methods. For example, according to the driving method, it can be divided into electric pumps and water turbine pumps; according to the structure, it can be divided into single-stage pumps and multi-stage pumps; according to the purpose, it can be divided into boiler feed water pumps and metering pumps; according to the nature of the conveying liquid, it can be divided into Water pumps, oil pumps and mud pumps, etc. According to the shaft structure, it can be divided into linear pump and traditional pump.