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oil sampling

oil sampling

oil sampling


Hi everybody,

I´m working with samples of hydraulic fluid doing particle counting with microscope acording to ISO 4406:1999.
In all cases I can see white, very bright particles (see attachment) which I can´t tell what they are.
I suspect they can come from ambient air here at my office (when opening and manipulating the samples), that is dust, pollen, etc. Is this possible, does anybody have any other clue?

RE: oil sampling

Can't really tell from that photo.

It could be bright metal (debris from very recent metallic wear).

It could be a precipitate caused by a reaction between incompatible additives (possible addition of transformer oil to a hydraulic system).

It could be small flecks of white paint that have been chewed up by the pump (what colour is the machine?)

It could be something in the air (is there a flour mill down the road? is the equipment used in the manufacture of powdered aluminium?)

You could send the sample away for a spectrocopic debris analysis for some additional information.

If you suspect its from the ambient air then what could it be? Dust (human skin cells mostly), Dandruff, cigarette ash, cigarette smoke? It would be simple enough to get some samples of these and check whether they look the same under the microsope.


RE: oil sampling

They look like small bits of metal that should be attached to the pump, or some other vital part of the system.

Dust, sand and biological structures don't show up like that under a microscope.

Unless in "manipulating" the samples you managed to throw them on the floor and then scrape them back into the sample bottles, this is system contamination.

The only was to be sure is to have them analysed with a spectrograph.


RE: oil sampling


Thank you for your thoughts folks!

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