Definition and classification of hydraulic pumps for semi trailers
Definition
A machine that relies on the change of enclosed working volume to suction and pressure liquids, thereby converting mechanical energy into hydraulic energy.
A hydraulic pump is the power component of a hydraulic system, which converts the mechanical energy of the prime mover into the pressure energy of the liquid. It refers to the oil pump in the hydraulic system, which provides power to the entire hydraulic system. The structural forms of hydraulic pumps generally include gear pumps, vane pumps, and plunger pumps.
Classification
Types of commonly used hydraulic pumps
1.According to whether the flow rate is adjustable, it can be divided into variable displacement pumps and quantitative pumps.
- The output flow rate that can be adjusted according to needs is called a variable pump, while the flow rate that cannot be adjusted is called a quantitative pump.
- According to the commonly used pump structures in hydraulic systems, there are three types: gear pumps, vane pumps, and plunger pumps.
Gear pump: small in size, simple in structure, not strict in oil cleanliness requirements, and relatively cheap in price; But the pump shaft is subjected to unbalanced force, severe wear, and significant leakage.
Vane pump: divided into double acting vane pump and single acting vane pump. This type of pump has uniform flow rate, smooth operation, low noise, higher operating pressure and volumetric efficiency than gear pumps, and a more complex structure than gear pumps.
Plunger pump: high volumetric efficiency, small leakage, can work under high pressure, mostly used in high-power hydraulic systems; But the structure is complex, with high requirements for materials and processing accuracy, expensive prices, and high requirements for oil cleanliness.
Generally, plunger pumps are only used when gear pumps and vane pumps cannot meet the requirements. There are also some other forms of hydraulic pumps, such as screw pumps, but their applications are not as common as the three mentioned above.
