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Figure 4 shows how oil analysis often
manifests ahead of vibration analysis in
the cases of bearing failure detection in
low-speed gearboxes.
Oil analysis also comes to the forefront
with mineral impurities and increased
amounts of metal particles (iron, steel,
copper, etc.). e elevation of these values
can be perceived early with oil analysis
before being identified by vibration analysis.
Vibration Analysis vs.
Oil
Analysis
ere are many examples of vibration
analysis and oil analysis working well and
complementing each other, such as for a
bearing lubrication failure or pinion tooth
wear detection. However, there are also cases,
such as with unbalance and misalignment,
when only vibration analysis can be applied.
On the other hand, identifying water in oil
will only be possible through oil analysis. Used
together, both techniques are valuable tools
Figure 9. Vibration trend for the reducer
Figure 12. The vibration spectrum for the lift gearbox
Figure 10. An example of a lift gearbox
Figure 11. Trend of increasing iron levels
in the lift gearbox
for root cause analysis and can help ensure the reli-
ability of an asset's condition. erefore, vibration
analysis and oil analysis are indispensable to any
maintenance program.
Case Study: Low-Speed
Gearbox Analysis
At the primary plant of a South American
manufacturer of vegetable proteins, many of the
machines are exposed to the outdoors. In this
location, there are two well-defined seasons: a
rainy summer and a dry winter. us, the assets
are vulnerable to external contamination if their
seals are inadequate. Early oil analysis results
illustrated these conditions well. is helped
the maintenance team deploy and improve a
protection system by installing devices to inhibit
contamination. e results were quite noticeable.
e plant soon discovered that oil analysis
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