Jaja...
Esters & PAO's, ik kon er ff niet opkomen. Leuk artikeltje voor je gevonden Mark:
Generally, the reference to synthetic oil for an engine, means a lubricant is formulated
with a polyalphaolefin (PAO) base oil. PAO, which is often called synthesized hydrocarbon,
is pure and is compatible with mineral base oils. However, because the PAO
base oil does not dissolve additives effectively, it is usually formulated with an ester
co-base (usually di-ester and/or polyol ester). The additives are soluble with the ester
and the ester is soluble with the PAO. Likewise, the PAO tends to cause seal shrinkage
and the ester causes seal swelling, so the effects are offset when both base oils are
present. It is the ester that can cause problems when one changes from mineral to
synthetic. Ester base oil used alongside PAO base oil in lubricant formulation has
excellent natural detergency. In other words, it will clean up varnish on component
surfaces as a result of thermal and oxidative degradation of the lubricant. When one
switches from a typical mineral-based engine oil to a typical synthetic-based oil, the
varnish layer will be removed by the ester in the synthetic oil and become suspended.
This suspended material can rapidly clog filters and can block oil flow passageways
and lead to component starvation. The same is true for gearboxes and other industrial
machines. So think twice about switching to synthetic oils in applications where the
engine or other machine has been operating for some time with mineral oils. If you
decide to make the switch, try to clean the system before making the change, then
monitor it carefully once you start it up.
Courtesy Drew Troyer Noria Corporation
www.noria.com