only to discover compressive heating and the resulting degradation
http://www.machinerylubrication.com/Read/475/oil-breakdown
http://www.machinerylubrication.com/Read/475/oil-breakdown
Just when we thought we were on top of degradation
- Thread starter jrustles
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Originally Posted By: jrustles
only to discover compressive heating and the resulting degradation
http://www.machinerylubrication.com/Read/475/oil-breakdown
We've touched on it before...
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2651368
I've seen improperly purged hydraulic cylinders go from micro, to full on dieseling...breaks stuff other than the oil 'then.
only to discover compressive heating and the resulting degradation
http://www.machinerylubrication.com/Read/475/oil-breakdown
We've touched on it before...
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2651368
I've seen improperly purged hydraulic cylinders go from micro, to full on dieseling...breaks stuff other than the oil 'then.
"Perhaps one of the earliest indicators is a change in the oil’s color. Like oxidation, thermal failure results in a change in oil color"
Wait...What?
So...Use a GF-5/SN conventional Group2(+) 5w20 or 10w30 and be nervous if the oil turns black early in the OCI.
Wait...What?
So...Use a GF-5/SN conventional Group2(+) 5w20 or 10w30 and be nervous if the oil turns black early in the OCI.
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Originally Posted By: Lex94
"Perhaps one of the earliest indicators is a change in the oil’s color. Like oxidation, thermal failure results in a change in oil color"
Wait...What?
So...Use a GF-5/SN conventional Group2(+) 5w20 or 10w30 and be nervous if the oil turns black early in the OCI.
If that's the case then the color of your oil might just have some meaning.......
"Perhaps one of the earliest indicators is a change in the oil’s color. Like oxidation, thermal failure results in a change in oil color"
Wait...What?
So...Use a GF-5/SN conventional Group2(+) 5w20 or 10w30 and be nervous if the oil turns black early in the OCI.
If that's the case then the color of your oil might just have some meaning.......
wemay
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Originally Posted By: Lex94
"PAO's and hydrocracked base oils may lay down varnish insoluble more readily than solvent-refined mineral oils - Ref ExxonMobil"
HeHe....
If true, i wonder what this would mean for blends?
"PAO's and hydrocracked base oils may lay down varnish insoluble more readily than solvent-refined mineral oils - Ref ExxonMobil"
HeHe....
If true, i wonder what this would mean for blends?
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OVERKILL
$100 Site Donor 2021
Originally Posted By: Lex94
"PAO's and hydrocracked base oils may lay down varnish insoluble more readily than solvent-refined mineral oils - Ref ExxonMobil"
HeHe....
Link?
"PAO's and hydrocracked base oils may lay down varnish insoluble more readily than solvent-refined mineral oils - Ref ExxonMobil"
HeHe....
Link?
OVERKILL
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Originally Posted By: Lex94
Link - In "Figure 5" of the linked article.
Maybe the Dexos synthetic blends have better overall performance than straight G2 conventionals...I like the new Quaker State SynBlend 0w20 Dexos - On paper.
See it now, thanks.
I guess it depends on what you take away from the statement in the context of the article:
Quote:
Perhaps one of the earliest indicators is a change in the oil’s color. Like oxidation, thermal failure results in a change in oil color, although typically early thermal failure causes a color change sooner than oxidative failure. The color change is due to the formation of carbon and oxide insolubles - chemical by-products of base oil breakdown, which are suspended in the oil. A number of tests including a simple patch test (using a 0.8mm patch or smaller), or an ultracentrifuge test that uses a high-speed centrifuge to remove suspended materials from the oil for visual examination (Figure 5) can provide an early warning sign of thermal failure.
I would take the statement to mean that it is more easy to extract the contaminant from those base oils using that test than other base oils
Link - In "Figure 5" of the linked article.
Maybe the Dexos synthetic blends have better overall performance than straight G2 conventionals...I like the new Quaker State SynBlend 0w20 Dexos - On paper.
See it now, thanks.
I guess it depends on what you take away from the statement in the context of the article:
Quote:
Perhaps one of the earliest indicators is a change in the oil’s color. Like oxidation, thermal failure results in a change in oil color, although typically early thermal failure causes a color change sooner than oxidative failure. The color change is due to the formation of carbon and oxide insolubles - chemical by-products of base oil breakdown, which are suspended in the oil. A number of tests including a simple patch test (using a 0.8mm patch or smaller), or an ultracentrifuge test that uses a high-speed centrifuge to remove suspended materials from the oil for visual examination (Figure 5) can provide an early warning sign of thermal failure.
I would take the statement to mean that it is more easy to extract the contaminant from those base oils using that test than other base oils
OVERKILL,
have a look at this also...
http://www.machinerylubrication.com/Read/23903/lubrication-varnish-removal
As I've been saying for a long while, GrI can hold more degradation product in solution, as it has way more polar sites...it's behaviour in service is "linear" and predicatble...it's always getting worse, but not an issue.
GrII/III, and IV are less polar, but more highly resistant to oxidation...they can show great "numbers" in oxidation tests, and still be laying down sludge/varnish at the same time...then they hit a "wall" and throw lots of sludge.
One of my undergrads did a thesis on varnish production, and detection using Membrane Patch Colorimetry (using a flat bed scanner), which was/is a test that's currently under review (not with a flatbed scanner) for acceptance as a proper test for oil degradation...who says blotter testing is wrong ?
It basically uses non polar solvents to dissolve the oil, then run it through a filter membrane to catch the varnish...measure the colour spectrum of the insolubles
http://www.microspectralanalysis.com/Technical/i-LAB MPC User Guide.pdf
have a look at this also...
http://www.machinerylubrication.com/Read/23903/lubrication-varnish-removal
As I've been saying for a long while, GrI can hold more degradation product in solution, as it has way more polar sites...it's behaviour in service is "linear" and predicatble...it's always getting worse, but not an issue.
GrII/III, and IV are less polar, but more highly resistant to oxidation...they can show great "numbers" in oxidation tests, and still be laying down sludge/varnish at the same time...then they hit a "wall" and throw lots of sludge.
One of my undergrads did a thesis on varnish production, and detection using Membrane Patch Colorimetry (using a flat bed scanner), which was/is a test that's currently under review (not with a flatbed scanner) for acceptance as a proper test for oil degradation...who says blotter testing is wrong ?
It basically uses non polar solvents to dissolve the oil, then run it through a filter membrane to catch the varnish...measure the colour spectrum of the insolubles
http://www.microspectralanalysis.com/Technical/i-LAB MPC User Guide.pdf
OVERKILL
$100 Site Donor 2021
Thanks for the info Shannow!
Page 18 of the following presentation shows panel coker test results with various base oils with only antioxidant added: http://www.eng.rpi-inc.ru/materials/26/neo364/DAY2/SESSION7/UniqemaEng.pdf
It's just an example and is obviously not fully formulated motor oil, but it's interesting to me.
It's just an example and is obviously not fully formulated motor oil, but it's interesting to me.
OVERKILL
$100 Site Donor 2021
Originally Posted By: JAG
Page 18 of the following presentation shows panel coker test results with various base oils with only antioxidant added: http://www.eng.rpi-inc.ru/materials/26/neo364/DAY2/SESSION7/UniqemaEng.pdf
It's just an example and is obviously not fully formulated motor oil, but it's interesting to me.
Yup, I recall seeing that in the past. Once PAO oxidizes.... as Shannow noted, wow.
Page 18 of the following presentation shows panel coker test results with various base oils with only antioxidant added: http://www.eng.rpi-inc.ru/materials/26/neo364/DAY2/SESSION7/UniqemaEng.pdf
It's just an example and is obviously not fully formulated motor oil, but it's interesting to me.
Yup, I recall seeing that in the past. Once PAO oxidizes.... as Shannow noted, wow.
Originally Posted By: Shannow
One of my undergrads
College professor? On another thread you're building wastewater plants.
On others you elude to being a steam turbine expert?
I'm confused.
One of my undergrads
College professor? On another thread you're building wastewater plants.
On others you elude to being a steam turbine expert?
I'm confused.
Originally Posted By: OVERKILL
Originally Posted By: JAG
Page 18 of the following presentation shows panel coker test results with various base oils with only antioxidant added: http://www.eng.rpi-inc.ru/materials/26/neo364/DAY2/SESSION7/UniqemaEng.pdf
It's just an example and is obviously not fully formulated motor oil, but it's interesting to me.
Yup, I recall seeing that in the past. Once PAO oxidizes.... as Shannow noted, wow.
Agreed....
Originally Posted By: JAG
Page 18 of the following presentation shows panel coker test results with various base oils with only antioxidant added: http://www.eng.rpi-inc.ru/materials/26/neo364/DAY2/SESSION7/UniqemaEng.pdf
It's just an example and is obviously not fully formulated motor oil, but it's interesting to me.
Yup, I recall seeing that in the past. Once PAO oxidizes.... as Shannow noted, wow.
Agreed....
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