Re: compress your own air?

Deane D McIntyre (dmcintyr@ucalgary.ca)
Tue, 06 Apr 1999 08:57:05 -0700

leonard charles dickinson wrote:
>
> I am interested in hearing from any members who compress their own air for
> SOLIDS NMR use. Specifically we have problems on our Doty 4mm/15kHz probe
> on the ASX300 using house air: when the AMX500 user (on same air circuit)
> ejects his/her/its sample the pressure drops enough to cause spinning to droop
> and thence become unstable. As we have tried all the measures which would up
> our flow and pressure using building air, we are having to look at buying our
> own compressor. I would like to know manufacturers, costss, models, capacity
> and experiences.
>

We are considering doing the same thing. We are presently a liquids only
operation, with a AM400 and AMX500, using compressed air provided by the
university at 45 psi. Air goes through a filter to remove oil mist and solids
before use. Works reasonably well except that due to water vapour content
low temperature work is sometimes a problem.

The 400 will be upgraded to solids in the future, and we are also purchasing
a third instrument (700+)(both solids and liquid capable). I understand
that we
need compressed air (or better nitrogen) at 60 psi or so. So we are considering
either our own air compressor, or producing compressed nitrogen either
by evaporation of liquid N2 or from some sort of extraction scheme from
the air.

Any comments would be most appreciated as we are now in the process of site
planning.

We are also interested in finding a suitable UPS (230 volt) for our
instruments.

Cheers, Deane D McIntyre
NMR Mananger
Dept Biological Sciences
University of Calgary

dmcintyr@ucalgary.ca