Avaliação de técnicas não convencionais de análise de vibração, para detecção de defeitos em máquinas rotativas horizontais

Abstract

In popular terms, it has been said that the machines speak and through sounds and vibration we can hear their complaints and diagnose their diseases . The condition monitoring of rotating machines by measuring and vibration analysis is the process in which a machine is periodically evaluated by measuring and analyzing its condition by means of vibration signals. This procedure can be carried out at three levels: 1-Overall measurement of vibration levels, to know the severity of vibration and compare with preset limits; 2- Frequency and time dominium spectrum analysis to detect where the defects come from; 3- Special techniques that can better detail the level, location and type of a defect or a malfunction. This study aims to evaluate some of these special techniques such as Full Spectrum, SPM spectrum, Órbita, phase analysis / ODS and Envelope. These techniques were applied on an experimental rig by imposing various defects in these mechanisms such as misalignment, imbalance, gear defects, problems in bearings, etc. and measuring its vibration response. The results obtained by each technique were evaluated and compared. The final analysis is made using the method of digital logic by creating tables of comparative techniques for each type of defect. Doing so, it way possible to identify which technique is best to diagnose a particular type of defect.