1. Structural form of plunger pump: piston pump is divided into two representative structural forms: axial piston pump and radial piston pump; Since the radial piston pump belongs to a new type of high-efficiency pump with relatively high technical content, with the continuous acceleration of localization, the radial piston pump will inevitably become an important part of the application field of piston pump. Plunger pump working principle Plunger pump is a kind of reciprocating pump, belongs to the volumetric pump, its plunger is driven by the eccentric rotation of the pump shaft, reciprocating movement, and its suction and discharge valves are check valves.

2. When the plunger is pulled out, the pressure in the working chamber is reduced, the outlet valve is closed, and when the inlet pressure is lower, the inlet valve opens and the liquid enters; When the plunger is pushed inside, the working pressure rises, the inlet valve is closed, and when it is higher than the outlet pressure, the outlet valve opens and the liquid is discharged.

3. Axial piston pump with sliding shoe structure is currently the most widely used axial piston pump, the plunger placed in the cylinder block is in contact with the swash plate through the sliding shoe, when the drive shaft drives the cylinder block to rotate, the swash plate pulls the plunger out or pushes back from the cylinder block to complete the suction and drainage process.

4. The oil in the working chamber composed of the plunger and the cylinder bore communicates with the suction and discharge chambers of the pump through the oil distribution plate.

5. The variable mechanism is used to change the inclination angle of the swash plate, and the displacement of the pump can be changed by adjusting the inclination angle of the swash plate.

6. Maintenance of piston pump Swash plate axial piston pump generally adopts the form of cylinder rotation and end face distribution.

7. The end face of the cylinder block is equipped with a friction pair composed of a bimetal plate and a steel oil distribution plate, and most of them use the method of plane distribution, so the maintenance is more convenient.

8. The oil distribution plate is one of the key components of the axial piston pump, when the pump is working, on the one hand, the high-pressure oil of the working chamber pushes the cylinder block to the oil distribution plate, on the other hand, the oil film pressure between the oil distribution plate and the cylinder block forms a hydraulic thrust back on the cylinder block to make the cylinder block deviate from the oil distribution plate.

9. The hydraulic compression force Fn of the cylinder block to the oil distribution plate is slightly greater than the hydraulic thrust reversal force Ff of the oil distribution plate to the cylinder block, that is, Fn/Ff=1.05~1.1, so that the pump works normally and maintains high volumetric efficiency.