MAINTENANCE PHILOSOPHIES
Industrial and process plants typically utilize two types of maintenance management:
(1) run-to-failure, or (2) preventive maintenance.
Run-to-Failure Management
The logic of run-to-failure management is simple and straightforward. When a
machine breaks, fix it. This ‘‘if it ain’t broke, don’t fix it’’ method of maintaining
plant machinery has been a major part of plant maintenance operations since the
first manufacturing plant was built, and on the surface sounds reasonable.
A plant using run-to-failure management does not spend any money on maintenance
until a machine or system fails to operate. Run-to-failure is a reactive
management technique that waits for machine or equipment failure before any
maintenance action is taken. It is in truth a no-maintenance approach of
management. It is also the most expensive method of maintenance management.
Few plants use a true run-to-failure management philosophy. In almost all
instances, plants perform basic preventive tasks (i.e., lubrication, machine
adjustments, and other adjustments) even in a run-to-failure environment. However,
in this type of management, machines and other plant equipment are not
rebuilt nor are any major repairs made until the equipment fails to operate.
The major expenses associated with this type of maintenance management are:
(1) high spare parts inventory cost, (2) high overtime labor costs, (3) high machine
downtime, and (4) low production availability. Since there is no attempt to
anticipate maintenance requirements, a plant that uses true run-to-failure management
must be able to react to all possible failures within the plant. This reactive
method of management forces the maintenance department to maintain extensive
spare parts inventories that include spare machines or at least all major components
for all critical equipment in the plant. The alternative is to rely on equipment
vendors that can provide immediate delivery of all required spare parts. Even if the
latter is possible, premiums for expedited delivery substantially increase the costs