The pump body and back cover of the bump adopt integrated design, cast iron as the shell material, roller needle bearing for bearing, axial floating side plate for clearance compensation and radial hydraulic pressure for partial balance structure. It has characteristics of high pressure, large output volume, reliable work, long service life, convenient maintenance, stable performance and so on. In terms of installation, there are a variety of connection types for choice, which can be also be used as a duplex pump. It is widely used in hydraulic systems such as construction machinery, mining machinery, metallurgical industry, chemical industry and so on.