Reliability Evaluation of Axial Piston Pump Based on Degradation Failure

Axial piston pump is very important in the hydraulic system, and its health affects the entire system directly. The wear and tear of the port plate pair is the main reason for the decrease of the axial piston pump pressure and flow rate. Therefore, the degradation test of the cylinder with the flow port plate pair and the port plate is studied. The wear and degradation trend of the port plate pair was evaluated according to the short-term reliability accelerated test method, and the model of the degradation of the port plate pair performance was changed with time. At the same time, the volumetric efficiency of axial piston pump is used as the degeneration standard of performance, and the volumetric efficiency is monitored in real time. The degeneration model of axial piston pump with the change of test time is established. Based on the two degenerative models, the relationship between the wear of the port plate pair and the performance degradation of the axial piston pump is established. The reliability of the axial piston pump can be evaluated by the wear and degradation data of the copper plating on the end face of the cylinder. Furthermore, based on the degradation efficiency of the volumetric efficiency of the axial piston pump, the optimal linear unbiased estimation method is used to evaluate the reliability of the axial piston pump test specimen. The results of the test show that the degradation characteristics of the hydraulic pump can be reflected by the degradation characteristics extracted from the time-varying flow signal, and the performance degradation parameters established by the cylinder port plate pair face and the port plate can accurately reflect the hydraulic pressure pump performance status degradation trend.