Pump as an important national production equipment, always with our lives closely related. As the saying goes, where there is water pump, more precisely there should be a place where there is a liquid pump, pump fluid handling industry as the most important one equipment, after so many years of development, structure and performance constantly Improve and improve, widely used in all walks of life in society, for our everyday life to provide convenience. Pump from the structure is divided into two major types of vane pumps and positive displacement pumps, in addition to some special types of pumps, such as jet pump, air lift pump, electromagnetic pump and so on. Vane pump type is very diverse, roughly a centrifugal pump, vortex pump, mixed flow pump, axial flow pump several types, of which the structure of the centrifugal pump has the most types, the most widely used. Centrifugal pump performance changes from 0 ~ 50,000 cubic meters / hour, head from 0 ~ 10000m range, corresponding to different models, different structures, different specifications of the pump everything. Centrifugal pump working principle is to rely on high-speed rotation of the impeller to produce centrifugal force to transport medium, the centrifugal pump performance is good or bad depends in part on a large number of pump design, due to a large number of centrifugal pump manufacturers, fierce competition led to domestic centrifugal pump in order to reduce costs, Most of the product performance can not meet the requirements of the country, during the 12th Five-Year, the state actively promote energy-saving emission reduction, centrifugal pump market needs to be optimized and improved. This year, the centrifugal pump market fell for a time, from another perspective, this is to promote the performance of the centrifugal pump industry is a catalyst. The development and application of axial flow pump will be substantially increased in the next few years. During the 12th Five-Year Plan period, the state has invested tens of billions of dollars to improve water pumping stations nationwide. Many domestic large-scale water conservancy projects have also been put on the agenda, Flow pump market has a huge stimulating effect. Positive displacement pumps are mainly reciprocating pumps and rotor pumps in two categories, including rotor pump gear pump, screw pump, cam pump (Roots pump), vane pump, hose pump several, reciprocating pump piston pump, diaphragm Pumps, metering pumps and several other. At present, the market share of positive displacement pumps is mainly controlled by foreign companies, and the domestic brands still need to be improved technically. With the significant increase in structure and performance of displacement pumps, their role in the fluid handling industry is also becoming more and more important. Positive displacement pump performance and pump structure design, manufacturing accuracy, so the performance of positive displacement pump generally higher than the centrifugal pump, which is also one of its competitiveness with the centrifugal pump. Positive displacement pump is the biggest advantage of being able to transport high viscosity, corrosive, high solids content such as centrifugal pump can not be delivered occasions, with the promotion of the market, the proportion of positive displacement pumps will continue to increase.