Does anyone know if additives have to be activated via temperature, use, pressure etc., for oils such as Tellus ? In other words, do these oils ( with additives ) change their properties - permanantly - as a result of temp change, use, pressure etc. ?

Regards

Pat

Some can - for example some VI improvers change shape in different temperatures. Tellus - like virtually every oil in the market has additives - what in particular are you trying to find out about the tellus range?

Thanks for the reply astrixstar.

We are using a mechansim which runs free during forced rotation ( very little friction ) but locks up once still ( very high local friction ). The rpm is very low and never exceeds approx 25 rpm. The problem we have is that the performacne characterisitcs have change within a few hours of use. We are certain that it is not the physical material but more to do with the oil characteristics. We are currently using Tellus 37 and have also tried Tellus 100 ( not the S or T types at this stage ) - both ok to start with but then the performance drops off. Starting temp is approx ambient - 20 deg or so and can raise to 50 deg C at peak althuogh temp is up and down with intermittant use etc., We are wondering if the oil perhaps lays down a film after use and if the additives become active and affects performance in other ways. There is nothing physically observable other than a change in performance. We change the oil to fresh and it all happens again. Best wishes. Pat

Hi Pat, you can monitor the consumption of additives by using the ICP and comparing the additive levels with the new oil, the additives do react and the chemical is used and locked up in a form the ICP can not "See" so you can tell as the additive package is used, this can appliy to any fluid and the labs can monitor user the "Ruler" system