Failure Mode
Excessive Belt Tension
Loose Connection
Worn Contactor
Figure 14 : Worn Contactor
Worn Liner
▪ What’s the one defect on
a rotating asset that
vibration won’t detect but
IR will? Yep, you read it,
excessive belt tension.
▪ Here we are looking
across three identical
pumps in operation.
Notice the delta-T of the
bearing housings on the
left of the image.
▪ Figure 4 is an example of
electrical IR. Notice the
temperature range on the right.
This is an important
consideration when trending
changes in temperature. Red can
be a false indicator if your range
is set too low.
▪ Figure 4 shows a loose electrical
connection defect or failure
mode. Notice that not only is
there a significant delta-T
between the ‘A’ and ‘B’ phase
connections, but that heat
resulting from the loose
connection is also creating a
potential defect in the wiring.
Figure 13: Excessive Belt Tension
Figure 14 13 : Loose Connection
This picture of a worn
contactor shows a
difference in temperature
on the ‘B’ phase.
Although it’s not a high
temperature, it’s still
abnormal and may be
indicating that it’s time to
change the contactor.
Here’s an example of a
mechanical IR application.
This is a drum dryer at a
phosphate plant. We
know that the
temperature of the
product entering the dryer
is in excess of 105 degrees
F. We can see here a
defect that indicates that
the liner within the dryer
has worn to the point that
product is seeping behind
the liner. This finding
enabled Planners to
schedule a liner
replacement during the
next outage.
Figure 15 : Worn Liner
