Ref. Fluid Life
especially wear particles. For example, the originating piece of
equipment can help associate reported wear particles with certain
internal components. The lubricant information can provide a
baseline for several parameters, such as the expected viscosity
grade, active additives and acid/base number levels. These details
may seem straightforward but are often forgotten or illegible on
the oil sample identification label or request form.
The next section (Section B) of the oil analysis report to
examine is the elemental analysis or FTIR breakdown. This data
can help identify contamination, wear metals and additives
present within the oil. These parameters are reported in parts per
million (ppm). Nevertheless, this does not mean a contamination
particle, for example, can only be indicated by sodium, potassium
or silicon spikes. In the example above, the rise in silicon and
aluminum could potentially indicate dust/dirt contamination as
the root cause. One likely explanation for these spikes is that as
dirt (silicon) enters the oil from an external source, three-body
abrasion occurs within the machine, causing wear debris including
aluminum, iron and nickel to increase.
With a better understanding of the metallurgy within the
system's components, any spikes in wear metals can be better
associated, allowing a proper conclusion as to which internal
components are experiencing wear. Keep in mind that for trend
analysis, it is important that samples are taken at an appropriate
and uninterrupted frequency.
With elemental data related to contaminants and wear metals,
alarms are set for upward trends in the data. For elemental data
pertaining to additives, alarms are set for downward trends. Having
a baseline of new lubricant reference data is critical in assessing
which additives are expected and at what levels. These baselines are
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