We operate a Mitsubishi single shaft steam turbine and combustion turbine with a combined control oil system. The fluid is maintained in relatively good condition with particulate and fullers earth filtration. The system was commissioned and filled with Shell Irus DR46. We are currently finding it more difficult to procure this product and have been informed that it may be out of production.

Can another manufacturer’s phosphate ester fluid be used for topping off the system?
Should I be concerned of incompatibility causing issues with the fluid?
Do other users have experience with mixing and using different brands?
Are users aware of any compatibility charts?

All assistance will be appreciated.

Best regards,
Scott

The DR 46 is a phosphate ester.

So there is hope.

We use a couple of different versions of Supresta Fyrquel that are phosphate ester based.

I would call them.

Regardless, get someone like Herguth to do full comapatibility testing.

Webster,

As long you stay with the same base oil (phosphate ester?) you will not see any problems because base oils of the same kind are compatible. What causes possible incompatibility are different additive packages used for blending final product.

Take the advice from RobertC and send sample of your in-service oil and a sample of new oil to Herguth Labs for compatibility testing. I'd suggest calling them first to discuss your case; whether ASTM D 7155 would be the most appropriate in your case (maybe Tier 1 or Tier 1 and Tier 2 analysis) or some other method. Make a habit of testing for compatibility every time you plan to buy new oil for use either as a make up oil or the replacement oil. Such approach is the best assurance that you will not have any problems which may be caused by possible incompatibility.

Thank you for your recommendations. I will post additional details of the analysis.

quote:

Shell Irus DR46

There are a number of products that would be equivalent but first you need some info. According to the Shell data sheet while this is a phosphate ester fluid, Irus D46 it does not appear to be an EHC quality phosphate ester. Compatibility testing will tell you nothing useful. But, do you have servovalves and at what pressure do you operate. If yes to servovalves, consider an EHC quality fluid like you have ICL (Israeli Chemical Limited who now own the phosphorous facilities of Supresta/Akzo Nobel/Stauffer) Fyrquel EHC, EHC-S or EHC-N or Chemtura Reolube Turbofluid 46XC, 46B or 46. Some of these contain triphenyl phosphate which has been considered a severe marine pollutant so review the MSDS's carefully. I would suggest EHC-N or 46XC with is a trixylenyl type of triaryl phosphate ester that has better air release and better hydrolytic stability but costs a bit more.

If not an EHC fluid then you have even more options like Fyrquel 220, Reolube Hyd 46XC and the like.

Ken

quote:

phosphate ester fluid

Dear sir,

Just make the filtration of your phosphate ester fluid or your oils is Ok. It's simple.

Kevin

Sorry, but using the proper technique to purify steam turbine oils and EHC fluid is not always "easy". You have to know the nature of the contamination and the consequences. For example, with a steam turbine oil it might be high water but you also have to check what impact this might have had on your rust inhibitors and if from a steam leak what imparct the hydrazine might have had on the oil. You might save the oil but wreck the equipment. Similarly with EHC a high particle count might mean particulates that are easy to remove but it can also mean fluid degradation which is not so easy. Many systems can reduce the acid number but not that many are effective in raising the resistivity which can be just as important.

quote:

Originally posted by EHCguy:
Sorry, but using the proper technique to purify steam turbine oils and EHC fluid is not always "easy". You have to know the nature of the contamination and the consequences. For example, with a steam turbine oil it might be high water but you also have to check what impact this might have had on your rust inhibitors and if from a steam leak what imparct the hydrazine might have had on the oil. You might save the oil but wreck the equipment. Similarly with EHC a high particle count might mean particulates that are easy to remove but it can also mean fluid degradation which is not so easy. Many systems can reduce the acid number but not that many are effective in raising the resistivity which can be just as important.

What you said is also the true problems existing on the filtration of steam turbine fluid. But as I know, there are some special high vacuum oil purifiers in the world can be used to filter such kind of special fluids without affecting any other systems.

I don't recognize your company. Is it the same as Yuneng or one of the many other vacuum dehydrator companies in Chong Qing? The machines all look the same to me, and they all have the same part numbers. I can only assume it is either the same company making all machines, or an intellectual property problem. Could you explain the situation for us so we don't make a mistake and buy from the wrong company?

Vacuum dehydrators are good at rapidly removing water from oil, but they tend to be overused. Oil, in transformers for example, can be made too dry. When one is permanently connected to a system, it is too easy for the operator to just push start as often as he feels necessary. They sometimes have a high heat density in their electric heater. They heat the oil as rapidly as possible in a short space and using the smallest heater possible. This exposes the oil to excessively high temperatures that results in oil degradation, varnish. This is the thing a purifier should be removing, instead of causing. The filter included with the dehydrator does nothing to remove this degraded oil, because it is below the range of normal filtration.

While a vacuum dehydrator is a great dehydrator, it is a bit of a stretch to call it a purifier. Maybe it would be better to call it a water removal system, or dewatering system. We at Isopur and my friends in the lubrication industry, who also make purifiers, Kleentek, Oilkleen and others, use electrostatic systems to remove submicron contamination, including varnish, to produce pure oil. We also use dewatering systems like yours, as well as, coalescers and drying filters when necessary to remove water from oil. In the case of EHC systems, the oil specific gravity is often greater than one, so a coalescer is out of the question. These electrostatic systems use different methods to use eletrostatics to remove particles that cannot be done using standard filtration but the result is the same, purification of oil. This is something a dewatering machine cannot do.