Application Note

Frontline mechanical maintenance teams need:
• Aquickscreeningtooltofitintoexistingrounds.
• Reliableandrepeatablemeasurementsofrotatingequipment
tomakeimperativego/no-gomaintenancedecisions.
• Abilitytotrendreadingsovertimeandnotifyaconsultantor
reliabilityengineerwhensomethingabnormalarises.
• Quickunderstandingofoverallmachineandbearingcondition,
todecideonrepairsandrepairequipment.
The benefits of
vibration screening
Vibration remains one of
the earliest indicators of
a machine’s health
Vibration can identify problems
before other symptoms, including
heat, sound, electrical consump-
tion, and lubricant impurities.
More than half of unplanned
downtime is attributed to
mechanical failures. While many
things can impact the life of a
machine, once the first signs
of failure appear, a machine
generally has only a matter of
months before failing completely.
Vibration testing provides a way
to determine where the machine
is on the failure curve and react
appropriately.
Vibration in rotating machin-
ery is merely the back and forth
movement or oscillation of a
machine and components, such
as drive motors, driven devices
(pumps, compressors, etc.), and
the bearings, shafts, gears, belts
and other elements that make up
mechanical systems.
Vibration itself is not the
problem. Excess vibration is a
symptom of internal issues, such
as bearing failures, imbalance,
misalignment and looseness that
shorten equipment lifespan.
Application Note
From the Fluke Digital Library @ www.fluke.com/library
ByJohnBernet
Point where
failure starts
to occur
Heat by touch P-F interval 1-5 days
F= Failure
P= Potential failure
Quantitative PM P-F interval 5-8 weeks
Wear debris in oil P-F interval 1-6 months
P
P1
P2
P3
P4
P5
P6
F
The P-F Curve, Adapted from John Moubray’s book “Reliability Centered Maintenance II”