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Bewildering Oil Analysis Results
Greg Combrink, Total Contamination Control Ltd.
1. Check that the sample procedure was followed and
that the possibility of organic material contamination
of the drawn sample (carbon based solids) was ruled out.
Did the sampler use the dusting cloth (filled with coal
dust) to wipe out a (certified clean container). Is the
sample representative of the system
2. Check turbine operational temperature record for any
high temps that could allow severe oxidation of the oil
into solid carbon.
3. Check that the analytical lab was returning good and
certified results, i.e. ask to see particle counter calibration
record and verify that the person running the test followed
procedure.
4.Check soot levels
Oil used in turbines in the past react with the modern
based oils to form grease like "particles" that
clog up oriface and passages etc. If one had to use a
container that had remnant newer based oil or alkaline
type based oil in it to top up the older turbine oil,
then a chemical reaction occurs forming the grease like
substance (organic contaminant (carbon and hydrogen)thus
not detected by typical machines used for SOAP).
Typically the old "acid plus a base reacts to form
a salt plus water" grade 10 chemistry applies but
in this case the "salt" is a "soap"
that precipitates out and absorbs oil forming the grease-like
substance that will be detected by particle counting but
not by the typical elemental analysis.
Thus go around and look for the offending contaminated
topping up container or go a search for the container
(probably still half full) of alkaline based oil that
had been added to the turbine system (it will probably
still be a "New Improved Formula" turbine oil.
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