Page 371 - Intro Predictive Maintenance

362 An Introduction to Predictive Maintenance

• Establish feedback that ensures completion of assigned lubrication and
follows up on any discrepancies.
• Develop a manual or computerized lubrication scheduling and control
system as part of the larger maintenance management program.
• Motivate lubrication personnel to check equipment for other problems and
to create work requests where feasible.
• Ensure continued operation of the lubrication system.

It is important that a responsible person who recognizes the value of thorough lubri-
cation be placed in charge of this program. As with any activity, interest diminishes
over time, equipment is modified without corresponding changes to the lubrication
procedures, and state-of-the-art advances in lubricating technology may not be
employed. A factory may have thousands of lubricating points that require attention.
Lubrication is no less important to computer systems, even though they are often per-
ceived as electronic. The computer field engineer must provide proper lubrication to
printers, tape drives, and disks that spin at 3,600 rotations per minute (rpm). A lot of
maintenance time is invested in lubrication. The effect on production uptime can be
measured nationally in billions of dollars.

Calibration
Calibration is a special form of preventive maintenance whose objective is to keep
measurement and control instruments within specified limits. A standard must be used
to calibrate the equipment. Standards are derived from parameters established by the
National Bureau of Standards (NBS). Secondary standards that have been manufac-
tured to close tolerances and set against the primary standard are available through
many test and calibration laboratories and often in industrial and university tool rooms
and research laboratories. Ohmmeters are examples of equipment that should be cali-
brated at least once a year and before further use if subjected to sudden shock or stress.

Standards. The government sets forth calibration system requirements in MIL-C-
45662 and provides a good outline in the military standardization handbook MIL-
HDBK-52, Evaluation of Contractor’s Calibration System. The principles are equally
applicable to any industrial or commercial situation. The purpose of a calibration
system is to prevent tool inaccuracy through prompt detection of deficiencies and
timely application of corrective action. Every organization should prepare a written
description of its calibration system. This description should cover measuring test
equipment and standards, including:

• Establishing realistic calibration intervals.
• Listing all measurement standards.
• Establishing environmental conditions for calibration.
• Ensuring the use of calibration procedures for all equipment and standards.
• Coordinating the calibration system with all users.
• Ensuring that equipment is frequently checked by periodic system or cross-
checks in order to detect damage, inoperative instruments, erratic readings,