Hey alls,
So I was approached by a company to try and help them clean up a sample of gearbox oil. They are getting severe levels of contamination (both water and particulate) in a relatively short amount of time due to the environment.
They sent me a 5 gallon pail of their used oil to run through my centrifuge. We used several different methods and tested each pass (pulled a sample of each near the end of each pass).
The first run was 3k rpm @ 180F - 5gph flow rate.
2nd pass was 6k rpm @ the same..
And the 3rd test was 2 passes at 6k rpm.
Particulate count and water was DRASTICALLY reduced as expected... additives appeared to stay in tact for the most part... some minor changes but nothing was flagged (lab tests were performed by the oil manufacturer).
The oddity is the viscosity changes. The dirty base sample had a viscosity of 146 @ 40C. The 3k pass, viscosity increased to 168. The 6k pass increased to 191 and the 2 pass at 6k increased again to 201. The 168 was marked as an "attention" and the 2 others were marked as "action required".
What would cause viscosity to increase? The only thing I can gather is MAYBE oxidation? Relatively high temp and lots of fluid movement... but I don't know and the lab didn't give any rhyme or reason to what would cause it.
The other thought is this isn't an independent lab... it's the manufacturer of the oil (which they purchase the oil from).
Thoughts? We're hoping to get them setup with some form of filtration. Every oil change is costing them $2k and they are getting 2-3 weeks out of it... roughly 129 hours of use.
Thanks for any input.
So I was approached by a company to try and help them clean up a sample of gearbox oil. They are getting severe levels of contamination (both water and particulate) in a relatively short amount of time due to the environment.
They sent me a 5 gallon pail of their used oil to run through my centrifuge. We used several different methods and tested each pass (pulled a sample of each near the end of each pass).
The first run was 3k rpm @ 180F - 5gph flow rate.
2nd pass was 6k rpm @ the same..
And the 3rd test was 2 passes at 6k rpm.
Particulate count and water was DRASTICALLY reduced as expected... additives appeared to stay in tact for the most part... some minor changes but nothing was flagged (lab tests were performed by the oil manufacturer).
The oddity is the viscosity changes. The dirty base sample had a viscosity of 146 @ 40C. The 3k pass, viscosity increased to 168. The 6k pass increased to 191 and the 2 pass at 6k increased again to 201. The 168 was marked as an "attention" and the 2 others were marked as "action required".
What would cause viscosity to increase? The only thing I can gather is MAYBE oxidation? Relatively high temp and lots of fluid movement... but I don't know and the lab didn't give any rhyme or reason to what would cause it.
The other thought is this isn't an independent lab... it's the manufacturer of the oil (which they purchase the oil from).
Thoughts? We're hoping to get them setup with some form of filtration. Every oil change is costing them $2k and they are getting 2-3 weeks out of it... roughly 129 hours of use.
Thanks for any input.
