Page 335 - Intro Predictive Maintenance

326 An Introduction to Predictive Maintenance

duction efficiency and product quality in the plant. This is accomplished by regular
monitoring of the mechanical condition, machine and process efficiencies, and other
parameters that define the operating condition of the plant. Using the data acquired
from critical plant equipment, incipient problems are identified and corrective actions
taken to improve the reliability, availability, and productivity of the plant.

Specific goals and objectives will vary from plant to plant; however, we will provide
an example that illustrates the process. Before goals and objectives can be developed
for your plant, you must determine the existing maintenance costs and other parame-
ters that will establish a reference or baseline data set. Because most plants do not
track the true cost of maintenance, this may be the most difficult part of establishing
a predictive maintenance program.

At a minimum, your baseline data set should include the staffing, overhead, overtime
premiums, and other payroll costs of the maintenance department. It should also
include all maintenance-related contract services, excluding janitorial, and the total
costs of spare parts inventories. The baseline should also include the percentage of
unscheduled versus scheduled maintenance repairs, actual repair costs on critical plant
equipment, and the annual availability of the plant.

This baseline should include the incremental costs of production created by cata-
strophic machine failures and other parameters. If they are available or can be
obtained, they will help greatly in establishing a valid baseline. The long-term
objectives of a predictive maintenance program are to:
• Eliminate unnecessary maintenance.
• Reduce lost production caused by failures.
• Reduce repair parts inventory.
• Increase process efficiency.
• Improve product quality.
• Extend the operating life of plant systems.
• Increase production capacity.
• Reduce overall maintenance costs.
• Increase overall profits.

Just stating these objectives, however, will not make them happen or provide the
means of measuring the program’s success. Establish specific objectives (e.g., reduce
unscheduled maintenance by 20 percent or increase production capacity by 15
percent). In addition to quantifying the expected goals, define the methods that will
be used to accomplish each objective and the means that can be used to measure the
actual results.

15.2 FUNCTIONAL REQUIREMENTS
Functional requirements will vary with the size and complexity of the plant, company,
or corporation; however, minimal requirements must be met regardless of the vari-