Can anyone point to the the major causes of water not seperation out from Turbine Lube. oils once the oil is in service for a long time. Is it the oxidation products that play a role in this or is it the degradation of the base stocks? Is there any way I can get hold of Base stocks for commercially available Lube oils? Thank you.

The recent (Dec 1, 2004) LubeTips newsletter had a blurb about oil demulsibility which also referenced and linked an article in one of the Noria Magazines. If you dont receive LubeTips you might subscribe it provides some interesting insight.

It is quite common for old lube oils to fail water separability test. How big of a concern it is? Well, it depends on the systems’ operational conditions, oil sump size (residing time of oil contaminated with water before it is pumped back into the system), and the rate of water ingression. If water ingression is relatively low (generated mostly by condensation and not coming from leaky coolers), than a low-flow off-line cellulose fiber filtration system hooked on the individual sump would keep the oil dry, and keep cleanliness in check. In addition, it is important to test oil frequently, which will enable you to detect presence of water as early as possible. At that point, a vacuum dehydrator comes pretty handy.

Certainly, you can buy base stock oil, but the question is – what for? There are no additives in it that are essential for R&O oils. Blending additives is a delicate process. You may not be able to achieve their proper balance, if adding them to you oil in your plant.