While maintenance strives to reduce risk by preventing failures, the typical focus of a repair is to restore normal operation. Unscheduled repairs make this focus necessary. When production is interrupted, that down time is usually not a good time to review the design of the equipment. Operators may be standing around with no other tasks assigned, and shipments might be late.
Scheduled repairs are a different story. Using predictive maintenance tools, we can often see an equipment condition that will lead to failure if intervention is not made. Suppose ultrasonic testing reveals that the bearings of a critical motor will fail in the next six to nine months. You now have the luxury of ordering a spare and arranging with a motor shop to repair this one. But why are those bearings damaged?
There’s significant cost involved in this repair. The risk management part of the maintenance function requires taking steps to prevent a recurrence. In this case, you’d make a list of all possible contributors to bearing failure (e.g., incorrect lubrication, improper bonding, load issues, etc.) and investigate for each one of them.
