Page 69 - Intro Predictive Maintenance

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BENEFITS OF PREDICTIVE

MAINTENANCE

Predictive maintenance is not a substitute for the more traditional maintenance
management methods. It is, however, a valuable addition to a comprehensive, total-
plant maintenance program. Where traditional maintenance management programs
rely on routine servicing of all machinery and fast response to unexpected failures, a
predictive maintenance program schedules specific maintenance tasks as they are
actually required by plant equipment. It cannot eliminate the continued need for
either or both of the traditional maintenance programs (i.e., run-to-failure and pre-
ventive). Predictive maintenance can, however, reduce the number of unexpected
failures and provide a more reliable scheduling tool for routine preventive mainte-
nance tasks.

The premise of predictive maintenance is that regular monitoring of the actual
mechanical condition of machine-trains and operating efficiency of process systems
will ensure the maximum interval between repairs; minimize the number and cost of
unscheduled outages created by machine-train failures; and improve the overall avail-
ability of operating plants. Including predictive maintenance in a total-plant manage-
ment program will optimize the availability of process machinery and greatly reduce
the cost of maintenance. In reality, predictive maintenance is a condition-driven pre-
ventive maintenance program.

The benefits that are derived from using predictive maintenance technologies depend
on the way the program is implemented. If the predictive maintenance program is
limited to preventing catastrophic failures of select plant systems, then that is the result
that will be derived; however, exclusive focus on preventing failures may result in a
substantial increase in maintenance costs. For example, a large integrated steel mill
was able to reduce unscheduled machine failures by more than 30 percent, but a review
of maintenance costs disclosed a 60 percent increase.

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