Contaminant identification.

Dear Ariel,

Other way to determine the problem could be:

Run a spechtometric analysis to your new ISO VG 220, new ISO VG 46 and your current oil with viscosity of 150 Cts. Then, you can compare the presence of additives in the samples (Ca, P, Zn, etc), and to determine, if you have had any contamination.

The oil could be contaminated (with gasses, fuels, deppending of the application), and viscosity has decreased. For this, you should run a typical tests package (TAN, Flash Point, Particle Count, Water, Metals, etc)

It would be very important to know a little more about the application, and the industry where this problem has happened.

Best Regards

Thanks for your reply.

analysis is one thing. but the source of ingression is another thing. you think it is vg 46 contamination so you do have an idea based from the equipment system. you need to understand how this could happen. now all i can assume is this vg 46 is bearing oil and vg 220 is for g/b. if so, if both components are in the same casing, the seal that meant to prevent oil ingression to g/b from bearing cavity may have fail.

Ariel,

Is it Slideway Oil which common used for Machining Application?

If yes.
As long as, the slide way oil is not contaminated by the cutting fluid, I am agree with Schmid. You can trace back from metal additive composition. Mostly hydraulic oil is higher in Zn. Slideway oil mostly higher in P.
Yes, I agree with you

Regards,

Nurudin

Thank you for your answers.
We run an IR of the contaminated sample, and clean products, there was some coincidences, singinifacatrives, as a matter of fact around 2900 cm-1 and 1000 cm-1, there was some peaks that help me to say, that in very general terms, the contaminated sample, had been in contact with the other lube. I repeat, based on the peaks coincidence of the contaminated sample and the clean samples.
Rudimentary but effective i think.
Thank you for your support. I will check the metallographic analysis to confirm.