A. Reasons for unstable pressure and vibration of piston pump

There may be various reasons for the pressure instability and vibration phenomena occurring during the operation of a piston pump, which mainly include the following points:

1. Large leakage: If the clearance of the pump is too large or the sealing is poor, such as the oil distribution plate being scratched by metal fragments, iron chips, etc., or the sealing surface of the check valve in the variable mechanism is not properly fitted, it will lead to increased leakage, which in turn affects the pressure stability of the pump and causes vibration.

2. Insufficient suction volume: When there is excessive resistance in the suction pipeline or insufficient oil replenishment, it can lead to insufficient suction volume of the piston pump, resulting in unstable pressure and vibration.

3. Poor control of the variable mechanism: For a variable displacement pump, if the control of the variable mechanism is poor, such as foreign objects entering the mechanism, leaving scratches on the control piston, or due to insufficient amplifier energy, damaged parts, etc., it can cause unstable movement of the control piston, leading to instability in flow and pressure, and ultimately resulting in vibration.

B. Methods to solve the instability and vibration of plunger pump pressure

Based on the above reasons, the following measures can be taken to address the issues of unstable pressure and vibration in piston pumps:

1. Replacement of damaged parts: For issues arising from excessive leakage or poor control of the variable mechanism, it is necessary to disassemble the hydraulic pump, replace damaged components such as the oil distribution plate and check valve, and enhance sealing measures to reduce leakage and stabilize pressure.

2. Adjust the variable piston: For the issue of low displacement caused by a too small inclination angle of the swash plate, the inclination angle can be increased by adjusting the variable piston, thereby increasing the displacement and stabilizing the pressure.

3. Enhance maintenance and upkeep: It is crucial to regularly maintain and upkeep the plunger pump. This includes inspecting and replacing severely worn parts, cleaning filters and oil circuits, and ensuring the lubricating oil is clean and sufficient. By enhancing maintenance and upkeep, the service life of the plunger pump can be extended, and the likelihood of malfunctions can be reduced.

In addition, for users of piston pumps, the following points should be noted: Firstly, ensure that the inlet and outlet pipelines of the piston pump are unobstructed to avoid excessive resistance; secondly, regularly check the sealing performance of the piston pump to ensure no leakage occurs; finally, for variable displacement pumps, special attention should be paid to the control and adjustment of the variable mechanism to ensure stable operation.

The above:  Guidelines for Disassembly and Component Maintenance Standards of Hydraulic Piston Pumps