Page 374 - Reciprocating Compressors Operation Maintenance

Preventive Maintenance for Reciprocating Compressors 359

Predictive Maintenance

The maintenance methodology known as predictive maintenance and
condition-based maintenance is attracting attention as a highly reliable
substitute for conventional periodic maintenance and overhaul.

Where preventive maintenance fails in efficiency, predictive mainte-
nance offers improvement. This method involves the use of real-time or
portable instruments such as vibration, infrared, and wear debris moni-
tors to recognize the symptoms of impending machine failure. Predictive
maintenance is an early warning technique to detect small amounts of
damage before they lead to catastrophic failure.

In the design, operation, and maintenance of mechanical systems,
quantitative wear data play varying roles. Unscheduled equipment shut-
down can be very expensive due to lost production or service. Real-time
monitoring of components has the added advantage of helping to identify
replacement parts before they are actually needed.
Predictive maintenance won't stop things from wearing, but it will
allow the freedom to schedule downtime to correct the problem. This is
the smart way to do it, rather than permitting the problem to develop into
a full-fledged failure.

PREDICTIVE MAINTENANCE vs. PERIODIC INSPECTION
MAINTENANCE

Predictive maintenance evolved from several basic facts:

* Certain vital parts last longer and operate better if not frequently
taken apart, but operation until complete destruction is not only fool-
ish, but unsafe, and costly.
* 99% of all failures are preceded by signs, conditions, or indications
of failure.
* Periodic inspection maintenance could disturb good parts.
»Assembly errors are possible whenever machines are taken apart.
* Running fit and finish are sometimes jeopardized during internal
component inspection.
* Dirt intrusion is likely whenever a machine is opened.