I am new to fluid testing have a question about optical particle counters that I hope you can help with.
I am planning on using a LPC LCM20 to test automatic transmission fluid in fleets of vehicles with various models of transmissions which may have new oil of different types/brands as well as used oil. The purpose of the testing is to identify excessive amounts of harmful wear particles and/or verify cleanliness levels. One of our customers has questioned the validity of testing automotive transmission fluid with optical particle counters because of comments in a report from one of the major oil companies that is also their oil supplier. In addition to particle counting, the oil supplier used UC (ultra centrifuge) equipment to test fluid samples from the customer. The comments follow. . .
"It should be noted that optical particle count instruments are based on the disruption of a light beam. Any material that disrupts the light beam will be counted as a particle and not all of these will be abrasive particles. Certain lubricant additives, particularly antifoam, viscosity index improver and detergent additives can be read as particles by the counter under certain conditions. For this reason, lubricants with higher levels of these additives, such as most automotive lubricants, will exhibit higher particle counts than lubricants with lower levels or different types of additives altogether, such as industrial lubricants."
My main question is how much variability in results can be related to differences in the oil additives in automotive transmission fluids (i.e. different brands or synthetic vs. non) ?
And, is laser particle equipment (Parker LCM20) a valid method for identification of excessive amounts of harmful wear particles in the fleets described above.
Thanks,
Gregg (newbie)
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