Helium Flow-Meters...Solved

Richard Shoemaker (rshoe@wwitch.unl.edu)
Tue, 16 Jan 96 17:06:48 CST

Dear All:

Again..THANKS for _all_ of the helpful info, and thanks
especially to Andy Rous for doing my thinking for me...I guess
too much football hype damages brain cells 8-).

The confusion, as I started to analyze all of the _tons_ of
responses I got, was what range I needed for my flow meter for
liquid Helium. About half specified 0-50 CC/Hr (which is the
approx. range of the Dwyer meters on my VXR/Gemini magnet leg),
and the rest indicated 0-1 SCFH as the range. Andy pointed out that
the 0-50 CC/Hr is calibrated in CCs of liquid volume. If I would have
thought about it for a few minutes, I'd realize that if the boiloff of my
Varian magnets were 4 cc/hr of GAS, I would never have to do a
helium fill <grin>.

Several respondents indicated that their gauges read 0-1 SCFH, and
they work well, and Andy did the rough calculation to confirm the
conclusion that the 0-50 CC/Hr is liquid volume.

The BEST deal is directly from Dwyer...

The part number os VFA-1, and sells for $19.40 each.

If you want Stainless-Steel fittings it's: VFA-1-SS (between $20 and $30),

and one with a variable valve is VFA-1-SSV (I wouldn't want a valve,
lest an ignorant person close the valve, and overpressurize the dewar 8-(
for $32.90.

FYI: Dwyer Instruments
P.O Box 373
Michigan City, IN 46361
(219) 879-8000 (sales)
(219) 872-9057 (FAX)

ALSO, MR-Resources sells the VFA-1-SS for $43.00, in case Dwyer is
out of stock, and you're in a hurry. I went the cheap route, and ordered
4 of the flowmeters wo/ hardware directly from Dwyer.

Thanks again for the assistance.

Rich Shoemaker

---
Richard Shoemaker, Ph.D.                        Phone--(402) 472-6255
Instrumentation Director, Chemistry             FAX----         -6964
Research Associate Professor, Chemistry
University of Nebraska-Lincoln   
URL:  http://wwitch.unl.edu/nmrlab.html