Hi Jason,

On our LASER fluorination line we have an Edwards DiffStak charged with
Fomblin oil, running at 50% input voltage via a Variac controller to prevent
the Fomblin from decomposing.  This is backed up by an Edwards E2M5,
specially degreased and filled with Fomblin rotary oil.  Edwards provided us
with the E2M5 pre-cleaned and ready for Fomblin oil, but I'm unsure if in
these days of RV3s if such a thing is still available.  Our pump maintenance
company simple degrease the pump with solvent for Fomblin use.

If I remember correctly, there are different grades of oil for diffs and
rotary pumps, but I'd need to check back a few years.  The diff oil is 5
years old and going strong.  We get about 5E-6mbar (Penning gauge)

Oh, if you accidentally chuck ClF3 down the system, nothing will get hurt
apart from any pirani heads.  The filaments, err, dissolve.


----- Original Message -----
From: "Jason Newton" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, January 30, 2001 5:00 PM
Subject: [ISOGEOCHEM] pumps and fluorination lines

> As Steve has suggested, we're probably going to order an oil diff pump
> backed by a rotary for our new laser fluorination line. However, the main
> worry is contamination of the oil and the prospect of changing oil which
> contaminated with F. What kind of oils are people using, and how often are
> the oil changes? Someone on this list once mentioned the possibility of
> Fomblin oils - can these be used with regular rotary pumps?
> cheers,
> Jason
> *********************************
> Dr. Jason Newton
> University of California Santa Cruz
> Department of Earth Sciences
> Santa Cruz
> CA 95064
> email: [log in to unmask]
> Tel: +1  (831) 459 5751
> Fax: +1  (831) 459 3074