What happen if my turbine oil present
a continuos increase in the oxidation pressence
and nitration and sulphur in the same levels?
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quote:What happen if my turbine oil present
a continuos increase in the oxidation pressence
and nitration and sulphur in the same levels?
If FTIR is showing an increase in oxidation, you should be concerned that the oil is degrading. This could result in varnish and sludge build-up in the system. I would recommmend that you check the RPVOT and varnish potential of the oil.
I can provide you additional information if you would like. You can e-mail me at gwagenseller@analystsinc.com.
Oxidation does not necessarily move in lock-step with nitration & sulfur levels in turbine oil.
Oxidation increase means your oil is degrading. That is normal, to some extent. How high is it and how quickly is it increasing.
Nitration is usually not an issue for turbine oils. Nitration is commonly a problem for natural gas engine oils and sometimes in gasoline engines that run very lean. You will occasionally see it in very high pressure hydraulic systems like plastic extruders.
Oxidation & nitration are calculated from a single FT-IR scan. You're not getting the nitration number because it means anything, you're getting it because in an automated UOA lab, it's easier to give it to you than to write a subroutine to pull it out of the turbine oil analysis.
Sulfur is from the oil as received. It's primarily from the base stock, but some may be from the antioxidant (not likely, compounds like TPPT & ZDDP are not usually used in turbine oils. I'd avoid using a turbine oil with sulfur-containing additives.) An increase in sulfur from a turbine oil means contamination.
Hope some of this helps.
Oxidation increase means your oil is degrading. That is normal, to some extent. How high is it and how quickly is it increasing.
Nitration is usually not an issue for turbine oils. Nitration is commonly a problem for natural gas engine oils and sometimes in gasoline engines that run very lean. You will occasionally see it in very high pressure hydraulic systems like plastic extruders.
Oxidation & nitration are calculated from a single FT-IR scan. You're not getting the nitration number because it means anything, you're getting it because in an automated UOA lab, it's easier to give it to you than to write a subroutine to pull it out of the turbine oil analysis.
Sulfur is from the oil as received. It's primarily from the base stock, but some may be from the antioxidant (not likely, compounds like TPPT & ZDDP are not usually used in turbine oils. I'd avoid using a turbine oil with sulfur-containing additives.) An increase in sulfur from a turbine oil means contamination.
Hope some of this helps.
This is a timely topic......
I have several hydro-turbines the run Conoco Multi-purpose R&O oil, with ISO of 68. A sample of new oil shows sulphur content of about 180 ppm. But I have several machines with highly elevated levels, some over 1,000 pm.
Does anyone have any ideas what would cause the elevated sulphur content?
thanks,
Stan
I have several hydro-turbines the run Conoco Multi-purpose R&O oil, with ISO of 68. A sample of new oil shows sulphur content of about 180 ppm. But I have several machines with highly elevated levels, some over 1,000 pm.
Does anyone have any ideas what would cause the elevated sulphur content?
thanks,
Stan
Typical base stock sulphur content of turbine oils
Group I wt.% 0.35
Group II wt.% 0.001
Maybe your oil has been contaminated with Group I
Group I wt.% 0.35
Group II wt.% 0.001
Maybe your oil has been contaminated with Group I
Turbine oil has inhabitor and anti rust property, sulphur compounds is important in Turbine oil. Hence, it has been contaminated by fuel oil.
If you are seeing an increase in sulfur in several machines that persists through multiple analysis cycles, it is very likely a real phenomenon. The first thing to remember about UOA is that it looks a lot more like an industrial process than our normal idea of "the lab". It's not unusual to see carryover in elemental analyses when the samples tested immediately prior had high levels of a particular element. That's more likely with metals tested by AA or ICP and less likely with methods like X-ray, which is usually used for sulfur.
So, I'm on board with the idea that you have a contamination, but I'm not ready to say "it's X". As my ex-wife can tell you, my psychic powers have been a great disappointment to anyone who ever relied on them.
What are the make-up rates for these turbines? Where is the make-up oil stored? Is there any chance of misapplication? Contamination with an engine oil containing sulfonate detergents will give you a sulfur increase. I don't see fuel oil as a likely contaminant, particularly in a hydro-turbine. I don't see where it would come from. You'd need a whole lot of Group I based product to get up to 1000 ppm (0.1%). Are you getting water into the oil? what is the sulfur content of the water that is pushing this these turbines? (Again, this is not very likely.)
Has there been any recent maintenance? Does anyone at your location subscribe to the bizarre but persistent belief that STP is good for rolling turbines on start-up? STP was originally just olefin copolymer (OCP), a VI improver. Over time, they started including additives so they could market it as "improved". These additives only throw off the balance in your engine oil by a little, but they can seriously screw up a turbine oil with regard to demulsibility, foam and deposit-formation.
Happy hunting.
So, I'm on board with the idea that you have a contamination, but I'm not ready to say "it's X". As my ex-wife can tell you, my psychic powers have been a great disappointment to anyone who ever relied on them.
What are the make-up rates for these turbines? Where is the make-up oil stored? Is there any chance of misapplication? Contamination with an engine oil containing sulfonate detergents will give you a sulfur increase. I don't see fuel oil as a likely contaminant, particularly in a hydro-turbine. I don't see where it would come from. You'd need a whole lot of Group I based product to get up to 1000 ppm (0.1%). Are you getting water into the oil? what is the sulfur content of the water that is pushing this these turbines? (Again, this is not very likely.)
Has there been any recent maintenance? Does anyone at your location subscribe to the bizarre but persistent belief that STP is good for rolling turbines on start-up? STP was originally just olefin copolymer (OCP), a VI improver. Over time, they started including additives so they could market it as "improved". These additives only throw off the balance in your engine oil by a little, but they can seriously screw up a turbine oil with regard to demulsibility, foam and deposit-formation.
Happy hunting.