About Preventive Maintenance Optimization

A PM optimization is composed of the following steps:

1. The calculation model is configured to acquire the necessary parameters, including Mean Time Between Failures (MTBF). MTBF is used to determine the probability that a piece of equipment will fail.
2. The cost ratio is determined. This ratio is the cost of planned Preventative Maintenance (PM) events versus the cost of unplanned maintenance events. You can manually enter the cost or select an existing query as the source of the cost data.
3. Based on the MTBF and the calculation of the ratios, the GE Digital APM system estimates the optimum time (interval) to maintain equipment. The cost per piece of equipment based on the Optimized Preventative Maintenance Interval is also displayed.
4. The GE Digital APM system creates optimization graphs, which gives the analyst the optimum time to conduct a repair or overhaul based upon the ratio of planned to unplanned repair costs. This ensures that repairs are conducted in a cost-effective manner, minimizing risk while maximizing time in service.

The limitation to using a PM optimization is it will always give a result for the statistical distribution on which it is based. This does not mean that it will always make sense to do a PM at the interval specified. In particular, design flaws that manifest themselves as poor reliability can more effectively be addressed through redesign rather than PM.