Research On Fault Diagnosis Method And Application For Rolling Element Bearing Based On Vibration Signal

The Rolling element bearing is the common component in machinery. Their running state will influence the performance of the whole machine directly. It is hard to distinguish variable faults of identical premonition territory in the rolling element bearings fault diagnosis. Single sensor detect has indeterminacy in fault assort.In common situation, a simple fault may have different symptoms. For exact diagnosis, we must have enough symptoms and make clear the relationship between failures and symptoms, in order that we can analyze fault through symptoms.In this paper, through vibration modality and fault symptoms, rolling element bearing fault was analyzed in different means such as time-domain analysis and time-frequency analysis. Data was gathered from factory, experiment table and computer emluator in order to study on parameter target and function GREEN mat belong to Time Domain analysis, together with Short Time Fourier Transform (STFT), Wavelet Transform and Wigner—Ville distributing that belong to Time-Frequency analysis. These methods were analyzed to find the dominance of them. In this paper, there are parts of work as follows:Firstly, From the starting point of formation of vibration signals, the rolling element bearing instinct vibration, nonlinear stiffness of inner, outer race and rolling elements, and vibration caused by assemble error. Builds vibration signal model with single defect on each component and analysis fault characters of the vibration signal, theory base was advanced to rolling element bearing fault diagnosis.Then, by the means of time domain analysis, Time Domain parameters target such as peak value, the average square root, kurtosis, abundant and impulse target taken as important parts in the analysis. Criterion of Non-Dimension Parameters Diagnosis was summed up, and were practiced well in the rolling bearings detect of rolling mill and fun.Thirdly, as the vibration signal of rolling element bearing is often non-stationary style, so Time-Frequency method was taken in use to distill the character of mechanical vibration. It was studied in practice of Short Time Fourier Transform (STFT), Wavelet Transform and Wigner-Ville distributing which is keenness to non-stationary signal.At last, the mapping relationship between dominance of methods and failure part vibration to summarize varies means syncretism detect way was founded.