lubrication limits??

[upm]

Gents,
how do i know what is the lubrication physical proporties limits? i.e. VI,poir point, TAN.....etc? the oil vendor will only provide the data sheet but not the speck. Furthermore, the metal ppm in the oil is the ky as well and all vendors will set 0 ppm (Ti,Fe,Si...)
i have a problem getting high Fe,Cu in iso VG 150 synthitc oil in a recip comp., i inspected the comp. for wear but every thing was good? where the Cu,Fe coming from.? inaddition, somtimes the metal ppm is varying without doing any changes?
have you came across such a buzzle?
pls. advice
upm

 

[diamondjim]

I would expect that some of the residuals
that you are speaking of are wear particles
from the bearing and or separators. What
kind of bearing and cage is being used?

 

[electricpete]

Your first question sounds very general. Suggest you look at these two:

http://www.herguth.com/technical/PHYSFRAME.htm

http://www.noria.com/

A limit for metal particles of course depends on the equipment. Copper is present in brass often used in wearing parts (also look for trace of zinc in brass wear). Sometimes analytical ferrography will help to characterize the source of particles. If you use a commercial lab to evaluate your results they will usually help you interpret them somewhat. We use Herguth and they are great help.