Vibrodiagnostics of technical conditions of worm gears from the driven shaft nonuniform rotation

The paper describes the use of angle encoders for vibrodiagnostics of slowly developing defects on the example of worm gears wearing during operation. Vibrodiagnostics of any rotary mechanisms, not only worm gears, is especially urgent in the field conditions, where access to diagnostic centers with highly qualified experts in the diagnosis of specific equipment is limited. To solve this problem, it is desirable to minimize the cost of diagnosis and to simplify its algorithm, which will allow users without special training in this area to apply vibrodiagnostics. At the same time, it is necessary to provide the desired quality of diagnosis. One promising approach to solve the problem is to use the information obtained from the analysis of the vibration signal of the angular movement of the output shaft (torsion vibration signal). Since even large external perturbations do not exert a noticeable effect on the rotational motion of the system under consideration, the vibration signal provided by the angle encoder contains practically no noise, which significantly simplifies its identification. However, there are no scientific data on the application of such sensors to the diagnosis of slow-growing defects that do not drastically change the form and spectrum of the vibration signal. The wear changes technical parameters of worm gears, particularly the dynamic component of the torque, which can lead to galling and adhesive wear. The paper presents the results of analysis of experimental vibration signals, a technique to determine diagnostic signs of worm gear wear by the methods of spectral analysis and mathematical statistics. The study has shown that the angle encoder is suitable for the vibration diagnostics of worm gears. Diagnostic signs of wear and galling in the vibration signal of torsion oscillations of the worm gear slow-speed shaft are found. The proposed method significantly simplifies the analysis of the vibration signal, minimizes the cost of diagnosis, and can be widely implemented, especially for rapid diagnosis (in the field conditions) and predicting the residual life of many rotary type mechanisms.

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