Study Of Automatic Testing And Fault Diagnosis For Rotating Bearing

At present, the rolling bearing vibrate test machines using in the factory are based on hand-testing. Workers listen to the voice of the vibration of the rolling bearing and then decide the quality. The trend of the bearing test is automation. Many factories have introduced pipelining technology. But the vibration test is still separated from the pipeline, operating by the worker. The automation of the rolling bearing testing is sorely needed by the market.Based on widely reading of references and understanding of bearing vibration test technology and bearing fault analysis theory, this thesis analyzes the relationship of the voice and the vibration of the bearing, putting forward the rolling bearing fault diagnosis method through the resonance demodulation and wavelet analysis. According to the fault frequency of the rolling bearing, we can estimate the fault source of the rolling bearing. Aiming at the deficiency of rolling bearing vibration test machine at present, we design the system of rolling bearing automatic testing based on PC control and analysis. This system can resolve the abnormal noise problem by introducing new parameters of the time domain. The system works well in practice.The main contents of the study are as follows:In chapter 1, the background and the significance of the study are stated. The development trend and the current research situations of fault diagnosis theory and the rolling bearing vibration test technology are introduced in detail. And the main content of the dissertation is proposed.In chapter 2, the mechanism of the rolling bearing vibration is analyzed in detail, based on the widely reading of references, and the relationship of the vibration and the noise of the rolling bearing is stated. It proves that we can study the vibration of the rolling bearing to solve the abnormal noise. At last we introduce the parameters in the time domain.In chapter 3, we discuss the theory of the rolling bearing fault diagnosis, mainly demonstrating resonance demodulation theory. After demonstrating the mathematic model of the rolling bearing resonance demodulation theory, we use Matlab to simulate the classic Fourier analysis and the wavelet analysis by using the fault bearing vibration signal.In chapter 4, the system of automatic rolling bearing testing is introduced in detail, including the structure of the system, the hardware and the software.In chapter 5, the study contents and conclusions of the dissertation have been summarized, and the further works have been forecasted.