Working Principle of Hydraulic Pump

Hydraulic pump is a kind of hydraulic element that provides pressurized liquid for hydraulic transmission.Its function is to convert the mechanical energy of power machines (such as electric motors and internal combustion engines) into the pressure energy of liquids.Output flow can be adjusted according to the needs of the variable called the pump, the flow cannot be adjusted called the quantitative pump.The pumps commonly used in hydraulic system are gear pump, vane pump and plunger pump.Gear pump: small volume, simple structure, the oil cleanliness requirements are not strict, the price is relatively cheap;But the pump shaft by unbalanced force, wear serious leakage.Vane pump: divided into double-acting vane pump and single-acting vane pump.This pump flow uniform, smooth operation, low noise, working pressure and volume efficiency than the gear pump, the structure is more complex than the gear pump.Plunger pump: high volume efficiency, small leakage, can work under high pressure, mostly used for high-power hydraulic system;But the structure is complex, the material and the processing precision request high, the price is expensive, to the oil cleanliness request high.Generally in gear pump and vane pump can not meet the requirements of the plunger pump.There are some other forms of hydraulic pump, such as screw pump, but the application is not as common as the above three.

Hydraulic Pump Maintenance Notes:
1.Check the internal leakage status of the moving arm cylinder.The most brief way is to raise the arm, to see if there is a significant ease of reduction, if the fall significantly open cylinder to see, seal ring such as has been worn should be replaced in time.
2.Check the operating valve.First clean the safety valve, check the valve core is not wear, such as wear should be replaced.If there is no change after the relief valve device, then check the wear condition of the operating valve core, its gap use limit is usually 0.06mm, wear severe should be replaced.
3.Measure the pressure of a hydraulic pump.If the pressure is low, then adjust, add pressure is still not up, clarify the hydraulic pump severe wear.