Liquid or liquid booster pumps are transporting machinery. It will be the prime mover of the mechanical energy or other external energy to the liquid, the liquid increases. Pumps are mainly used for water, oil, acid and alkali, emulsion, suspension emulsion and liquid metals, liquids, but also transport liquid and gas mixtures and liquids containing suspended solids. Pump usually works can be divided into positive displacement pump, power pump, and other types of pumps in three categories. In addition to the principle of classification, classification and nomenclature also by other methods. For example, classified according to the driving method for electric pumps and hydraulic pump; classified according to the structure of single-stage pumps and multistage pumps can be classified by use of boiler feed water pumps and metering pumps, etc; classified according to the nature of the conveying liquid such as water pump, oil pump and pump. According to the non-axis structure can be divided into linear pumps, and pumps.