Performance Reliability Modeling And Maintenance Policy Optimization Of Axial Piston Pump

Axial piston pumps,which were called the heart of the hydraulic system,were widely used in aviation,military,heavy-duty mobile machinery and other fields because of its uniform of flow rate and high volumetric efficiency.The reliability,economy and safety of axial piston pumps can be effectively improved by timely and correct maintenance decisions.As one of the maintenance policies,preventive maintenance was widely discussed because of the improvement of the reliability of the equipment,whereas the performance degradation modeling was the main factor for making a PM policy.The equipment was usually periodically inspected to obtain its current level of degradation.In decision-making of a maintenance policy for a degradation system based on the inspection policy,current periodic inspection strategies have been widely used due to its relatively simple implementation.Periodic inspection strategies were usually difficult to implement on time because of the influence of some random factors such as maintenance power,transport time and external environment.The inspection policies in engineering practice were usually carried out randomly in inspection window in the form of a quasi-period.Therefore,how to establish a performance degradation model for an axial piston pump and based on which to establish a quasi-periodic inspection and maintenance policy become a new issue considered in this paper.With this purpose,the following content is the main topics discussed in this paper:(1)Combined with the structure and failure mechanism of the axial piston pump,the leakage and parameters which caused random degradation of the main friction pair was analyzed,which provided a theoretical basis for studying the maintenance policies of the axial piston pump.(2)The degeneration process modeling of the axial piston pump was proposed.The degradation path model and the typical stochastic process model(Gamma process and Wiener process)were used to model the degradation data respectively.The actual degradation datum of a type of piston pump was used to illustrate the modeling process.Optimal model selection method was used to optimize the proposed models.(3)The quasi-periodic inspection and maintenance policies based on axial piston pump were discussed.Modeling and optimization the quasi-periodic inspection and replacement and preventive maintenance policy were also analyzed.The actual degradation datum of a type of piston pump was used to illustrate the modeling and optimization process.The sensitivity analysis of the key parameters of the model and example verification was also carried out.