B4 - Vibration analysis

Abstract

This chapter focuses on vibration analysis. Vibration analysis uses vibration measurements taken at an accessible position on a machine, and analyses these measurements in order to infer the condition of moving components inside the machine. Furthermore, the chapter discusses the overall level monitoring. It is the simplest method for the vibration monitoring of complete machines. It uses the cheapest and most compact equipment. It has the disadvantage however that it is relatively insensitive, compared with other methods, which focus more closely on to the individual components of a machine. The overall vibration level can be presented as a peak to peak amplitude of vibration, as a peak velocity or as a peak acceleration. The normal procedure is to measure the vertical, horizontal and axial vibration of a bearing housing or machine casing and take the largest value as being the most significant. This chapter also describes discrete frequency monitoring.