Abstract
Operating a plant at off-design conditions can incur many penalties, some immediate, some long range. An immediate penalty could be increased unit energy costs and possibly product quality deterioration. A long-range penalty will be possible exposure of machinery to possible overload, surge, or various system upsets which can deteriorate components, accelerate wear, and set up problems such as misalignments which may interrupt production months from the time of occurrence. Downtime, whether planned or unscheduled, results in increased costs and in lost production. All machinery inevitably develops problems. The basic issue is preventing these problems from destroying machinery, endangering personnel, or upsetting production schedules. Knowing the operating condition of plant machinery and demonstrating an ability to schedule downtime for periods of minimum penalty is a large measure of the maintenance planner's effectiveness.
Babson, P. E. (1979). Using Signature Analysis for Maintenance Planning. Energy Systems Laboratory (http://esl.tamu.edu). Available electronically from
https : / /hdl .handle .net /1969 .1 /93845.