Preventive Maintenance

Preventive maintenance refers to a series of actions that are performed on either a time-based schedule or a schedule based on that of machine-run time. These actions are designed to detect, preclude, or mitigate degradation of a system (or its components). The goal of a preventive maintenance approach is to minimize system and component degradation and thus sustain or extend the useful life of the equipment.

The U.S. Navy pioneered preventive maintenance as a means to increase the reliability of its vessels. By simply expending the necessary resources to conduct maintenance activities intended to be used by the equipment designer, equipment life is extended and its reliability is increased. In addition to an increase in reliability, more money is saved than when using a program of reactive maintenance. Studies indicate that this savings can amount to as much as 12% to 18% on average. Depending on the facility's current maintenance practices, present equipment reliability, and facility downtime, there is little doubt that many facilities purely reliant on reactive maintenance could save much more than 18% by instituting a proper preventive maintenance program.

While preventive maintenance is not the optimum maintenance strategy, it does have several advantages over that of a purely reactive program. By performing preventive maintenance on equipment as the equipment designer envisioned, the life of the equipment will be extended. This translates into dollar savings. Preventive maintenance, like lubrication and filter changes, will generally allow the equipment to run more efficiently and result in dollar savings. While it will not prevent catastrophic equipment failures, it will decrease the number of failures and equipment downtime. Minimizing these failures translates into savings in both maintenance and capital equipment costs.

Advantages and Disadvantages

Advantages

Is cost effective in many capital intensive processes and equipment
Provides flexibility for the adjustment of maintenance periodicity
Increases component life cycle
Generates energy savings
Reduces equipment and/or process failures
Results in an estimated 12% to 18% cost savings over that found in a reactive maintenance program

Disadvantages

Does not eliminate catastrophic failures
Is more labor intensive
Includes performing unneeded maintenance activities, which has the potential to result in incidental damage to components