What is hydraulic pump ?
Hydraulic pump, definition: Driven by an engine or an electric motor, a hydraulic system power component that converts mechanical energy into hydraulic energy  .
It is the power element of the hydraulic system, which is driven by the engine or electric motor, sucks oil from the hydraulic oil tank, forms pressure oil and discharges it, and sends it to the actuator. Hydraulic pumps are divided into gear pumps, plunger pumps, vane pumps and screw pumps according to their structure
Types of commonly used hydraulic pumps:
1. According to whether the flow can be adjusted, it can be divided into: variable pump and quantitative pump. The output flow can be adjusted according to the needs is called the variable pump, the flow can not be adjusted called the quantitative pump.
2. According to the pump structure commonly used in the hydraulic system, it is divided into three types: gear pump, vane pump and plunger pump.
Gear pump: Smaller in size, simpler in structure, less strict on oil cleanliness, and cheaper in price; but the pump shaft is subjected to unbalanced forces, causing serious wear and leakage.
Vane pump: divided into double-acting vane pump and single-acting vane pump. This kind of pump has uniform flow, stable operation, low noise, higher operating pressure and volumetric efficiency than gear pumps, and more complex structure than gear pumps.
Piston pump: high volumetric efficiency, small leakage, can work under high pressure, and is mostly used in high-power hydraulic systems; but the structure is complex, the requirements for materials and processing precision are high, the price is expensive, and the cleanliness of the oil is high.
Generally, the plunger pump is used when the gear pump and the vane pump cannot meet the requirements. There are also some other forms of hydraulic pumps, such as screw pumps, etc., but their applications are not as common as the above three.