Research On The Wear Fault Signature Of Piston Pump Based On Rigid-flexible-fluid Coupling Analysis

Axial piston pump as a hydraulic pump,is a reciprocating rotating machinery,the pressure is high,the flow is large and thus widely used in construction machinery,mining machinery and other equipment,due to its poor working environment,the probability of failure,Many of its components lead to failure and location difficult to determine.In this paper,a kind of variable axial piston pump is taken as the object of study.With its virtual prototype model as the core,the quantitative fault research is carried out,and the fault response is obtained and analyzed for the different fault degree.Quantitative fault diagnosis research provides the basis and new ideas.The main research work and achievements are as follows:(1)Based on the analysis of the structure and assembly relationship,the three-dimensional model is established,and the working principle of the pump is introduced.The dynamic characteristics of the pump are analyzed,and the swash plate and column The pressure equation of the plunger shoe and the trajectory equation and the moment equation of the swash plate are obtained.The fluid characteristics of the pump are analyzed and the theoretical flow is calculated and the correlation formula of the pulsation rate is obtained.The vibration mechanism and the vibration transmission path of the pump pressure flow are analyzed,and the vibration path is modeled,which is the basis of the determination of the flexible components.(2)The multi-rigid-body dynamics model is established.On the basis of kinematics and mechanics analysis,the coupling relationship between the pump and the motion coupling between the parts is analyzed,and the constraint type table is obtained.The rigid body dynamics model of the pump is built and the kinetic model is studied.(3)Hydraulic model is established.The hydraulic model of the pump is established based on the fluid characteristic and the power bond graph theory,and the model is used to analyze the influence of the pump under different factors.The model of the pump is established by the model analysis.The dynamic performance of the results,combined with the theory of the results of the analysis of the model;(4)The rigid-flexible-fluid coupling model is established.According to the analysis of vibration transmission path and the conclusion of modeling analysis,11 parts such as plunger,spindle,pump,pump shell and roof are needed to be flexible and the flexible body model is established.Using the model of plunger stress and strain are analyzed,from the point of view of fatigue wear reveal the prone position and wear mechanisms of wear and tear;(5)The failure characteristics of the pump is studied based on the rigid and flexible fluid model.On the basis of coupling model,the plunger wear mechanism is theoretical analyzed and its leakage model is established,the fault response of the failure different levels were analyzed;Piston pump vibration test bed is built,from the theoretical and experimental point of view of the analysis and verification,analysis of model simulation results and theoretical calculations show that the parameters of the proposed model of the constraints set reasonable,the model is correct;the piston pump failure simulation Experiment,the experimental results were analyzed,and the accuracy of the method of fault analysis was verified.Results indicate that coupling model based on the rigid-flexible-fluid plunger pump failure analysis method is effective and feasible.The research achievements of this paper have some reference value for understanding the complex mechanical properties and fault characteristics of plunger pump,providing a new train of thought that fault diagnosis of plunger pump is researched.