5 - Machinery fault diagnosis using vibration analysis

Abstract

The progress made in engineering and materials science resulted in rotating machinery to become faster and lightweight; it is also required to run for longer periods of time. All of these factors mean that the detection, location, and analysis of faults play a vital role in the quest for highly reliable operations. Using vibration analysis, the condition of a machine can be constantly monitored. This chapter provides the methods of correlating rotating machine defects to vibrations collected and displayed by the various types of analyzers. Some of the machinery defects detected using vibration analysis are: unbalance, bent shaft, eccentricity, misalignment, looseness, and belt drive problems. When a bent shaft is encountered, the vibrations in the radial as well as in the axial direction are high. Axial vibrations may be higher than the radial vibrations. Furthermore, misalignment is a major cause of machinery vibration. Some machines are incorporated with self-aligning bearings and flexible couplings that can take quite a bit of misalignment.