Hydraulic pump hydraulic system to provide a certain amount of pressure and flow of oil power components, it is an indispensable core component of each hydraulic system, a reasonable choice of hydraulic pump to reduce the hydraulic system energy consumption, improve system efficiency, reduce noise and improve Work performance and to ensure the reliable work of the system are very important. Select the principle of the hydraulic pump is: According to the host operating conditions, power and system performance requirements, first determine the type of hydraulic pump, and then press the system required pressure, flow size to determine the size of its specifications. Table 3-1 lists the main hydraulic pump performance of the hydraulic system. Table 3-1 Performance Comparison of Hydraulic Pump Commonly Used Hydraulic Pumps Generally speaking, due to the prominent features of various types of hydraulic pumps, their structure, function and operation mode are different. Therefore, the suitable hydraulic pump should be selected according to different application occasions Hydraulic pump. Generally in the hydraulic system of the machine tool, the double-acting vane pump and the variable-pressure variable vane pump are often used. In the road construction machinery, port machinery and small-sized construction machinery, the gear pump with strong anti-pollution ability is often selected; when the load is large and the power Large occasions often choose plunger pump.