E-Book : Basic Vibration Primer

In the competitive realm of industry, a company must be able to produce defect-free products while maintaining a competitive price. In order to achieve this goal, cost-effective maintenance must be performed on the machinery used. To keep maintenance costs down, unexpected failures must be minimized or eliminated and all machinery shutdowns for maintenance should be planned. All of these concepts are included in the Reliability-Based Maintenance ^TM(RBM)^TM philosophy. This philosophy involves the concepts of Preventive, Predictive, and Proactive Maintenance. This paper will primarily focus on the Predictive maintenance technique.

Before predictive maintenance came on the scene, most maintenance was performed using either the Run-to-Failure or Preventive maintenance philosophies. These philosophies, however, proved to be less cost effective than their successors. By allowing a machine to run until failure, the repair costs escalated dramatically. In general, the repair would involve more repair parts, longer shutdown periods, and more labor to complete.

Preventive maintenance allowed a calendar, or some type of schedule to govern the repair work, whether it is needed or not. By performing this type of maintenance, some of the repairs that were being performed were unnecessary. Parts that were in good condition and performing well were being replaced. This caused the repair costs to escalate because of the amount of repair parts being consumed. Also, some of the work took out good parts and replaced them with "new" parts, some with preexisting defects, that caused problems in a short period of time.

Predictive maintenance then became the new kid on the block, in particular, the vibration monitoring technology. This technology has been around for decades, even though many of today's maintenance personnel tend to think that this is totally new. The use of state-of-the-art digital equipment is relatively new and continuing to improve as time progresses. The remainder of this paper will focus on the discipline of vibration monitoring. It will present some of the basics about establishing a vibration monitoring program as well as discuss some of the basic machinery faults that are detectable with vibration analysis.