Research On Condition Monitoring And Diagnosis System Of Sliding Bearing Based On Acoustic Emission Detection

Sliding bearing is one of the pivotal parts in large power machine, and it has an essential influence on the operating safety and reliability of the whole unit. There are a lot of factors which affect the conditon of sliding bearing, including the internal causes such as the type and the material of the sliding bearing, and also including the external causes such as the operating condition and overhaul craft.AE signals have good corresponding relationships with the condition of sliding bearing. Taking LabVIEW as the software development platform, the condition monitoring and diagnosis system of sliding bearing based on acoustic emission detection is developed in this paper. The hardware of the system includes AE sensors, signal-amplifier, signal separator, data acquisition card and computer. After the integration of hardware and software, the aquired condition monitoring and diagnosis system of sliding bearing can realize following functions: (1) Acquisition and filter of AE signal. (2) Signal analysis, including spectral analysis, specific energy computation, ringing count rate computation, event count rate computation, signal center frequency computation, autocorrelation analysis, and frequency spectrum energy instability computation. (3) Linking with the AE characteristic database of the condition of sliding bearing, the system could extract the character, and diagnoze the conditon of sliding bearing.Using the condition monitoring and diagnosis system of sliding bearing developed in this paper, the sliding bearing experiment is carried out on the rotor test platform in the laboratory, so as to inspect the accuracy of the AE parameters tested by the monitoring system under several rotational speeds. And also the typical failure conditions of sliding bearing are simulated, the system developed in this paper is used to diagnose the failure of the sliding bearing. The experiment result shows that the system test error satisfies the request basically, and the AE signal acquisition function and analysis function of the system is good. The system can accurately recognize the failure simulated. The system has quick response speed, high examination precision, simple operation performance, friendly man-machine interface, and good maintainability. It is of good engineering application value.