Research On In-situ Detection And Fault Diagnosis Technology Of Hydraulic System Of Construction Machinery

The hydraulic system of construction machinery plays an important role in the field of construction machinery.With the continuous updating of construction machinery and equipment,the testing,detection and fault diagnosis of hydraulic system also need to keep pace with The Times.When the hydraulic system of construction machinery fails,it is necessary to stop the machine to find out whether there is an obvious fault.If there is no obvious fault,it is necessary to disassemble the hydraulic components that may fail,and then send them to the hydraulic test bed for further detection and analysis to determine the cause and location of the fault.In this way,it will consume a lot of time and energy,affecting the work efficiency of engineering machinery and equipment.Therefore,it is necessary to study a new test and diagnosis method of hydraulic system to improve the efficiency of detection and solve the difficult problems of hydraulic system of construction machinery easily and quickly.Starting with the working principle and failure mechanism of the hydraulic system of construction machinery,this paper analyzes the failure reasons of the commonly used hydraulic components.The hydraulic propulsion system of shield machine and the hydraulic system of excavator are selected as the main research objects,and the working principle and failure reasons of the hydraulic system are analyzed.Based on the principle of hydraulic components do not into mechanical,establish the in-situ detection for the hydraulic system of engineering machinery,chose the pressure signal and traffic signal,vibration signal,temperature signal,and the oil data as the hydraulic system fault detection,using portable hydraulic tester and active hydraulic tester is completed for propulsion system of shield machine and test in the diagnosis of excavator hydraulic system.The in-situ detection system of the hydraulic system of construction machinery is developed,which is equipped with hardware such as sensors,signal conditioning module,signal acquisition instrument and auxiliary test equipment.The signal acquisition platform based on virtual instrument is built,and the in-situ detection software system of the hydraulic system of construction machinery is developed by using Lab VIEW.In this paper,the fault diagnosis of the hydraulic system of shield machine and excavator is studied.The fault tree model of the hydraulic system of excavator and excavator is established,and the direction of testing and diagnosis is determined by qualitative and quantitative analysis.Active static detector and portable hydraulic tester are used to test the hydraulic system,and the diagnosis conclusion is obtained.It is proved that the combination of fault tree analysis method and in-situ detection scheme has a good guiding significance for the detection and diagnosis of construction machinery hydraulic system,and the feasibility of in-situ detection technology and fault tree analysis method is verified.