Hi all,
I'm humbled by the amount of support shared in public and private over the
past few days. There's a general consensus that back pressure is much too
high while filling my magnets since we installed helium recovery. Many of
you offered suggestions and optimizations to help address it, which will
inform my setup and procedures going forward. I'll try to summarize the
discussion's main takeaways. Apologies for anything not mentioned, there's
just too much detail contained in these messages to do it all justice.
-The "usual" fill procedure everyone knows comes from before the days of
helium recovery. The transition to having it can mean adjusting your routine.
-Helium collection apparatus puts additional back pressure on the magnet. This
is generally inversely proportional to the receiving volume for helium exhaust.
Pressures from bag collection systems are seemingly less harsh than those with
medium pressure storage tanks/cylinders. Check valves in line with exhaust
also increase pressure.
-Pressure within magnet relieves slowly over may minutes rather than a few
seconds. Pulling the stinger "hot" from magnet at end of fill can agitate the
system due to larger pressure differential to atmosphere. Beneficial to slow
down transfer rate and let magnet settle somewhat first. How you approach that
would depend on your fill equipment.
-There are several strategies for tracking fill progress. The ones beyond the
liquid level meter require some setup. Nothing difficult, just a matter of
preparation and record keeping. Pressure gauge directly on magnet exhaust
port. Pressure within header line. Stored pressure within bag/cylinders/MPT's.
There's a lot of room for creativity on this subject.
Kind regards,
Luke
Luke Fulton, PhD
CHEM BLDG R003
NMR Core Facility Director
Unit 3060
COR2E & Department of Chemistry
55 N Eagleville Road
University of Connecticut
Storrs, CT 06279
email: fko24003_at_uconn.edu
(alias): luke.fulton_at_uconn.edu
mobile: (603) 953-5275
Office: (860) 486-4069
________________________________
> From: main_at_ammrl.groups.io on behalf of gregory.wylie via groups.io
> Sent: Monday, April 21, 2025 9:01 AM
> To: main_at_ammrl.groups.io
> Subject: Re: [AMMRL] Quench narrowly avoided? Filling small magnets connected to helium recovery
Hello
There have been lots of good ideas presented already but I would like to throw
out a couple more.
One in the pictures you posted the main flow during a fill would be directly
into the side of the tee. Personally I would redo the tee so the main flow
would go straight and the boil-off gas would be on the side.
Second, make sure that you don't have a restriction somewhere else in the
system. I have seen at least 2 times where a company set up a tank in front
of the pump/compressor and they took the 2 in main line to 1/4 in inlet of
this tank. These incidents were on medium pressure systems. So boil-off
will not be an issue but a fill would definitely be an issue!
Good luck.
Greg
Gregory P. Wylie, Ph.D
NMR Facility Manager
Texas A&M University
Department of Chemistry #3255
580 Ross St.
College Station, TX 77843-3255
gpwylie_at_tamu.edu
979.458.0705 (voice)
979.845.4719 (fax)
706.206.0007 (cell)
http://nmr.tamu.edu
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#2261): https://urldefense.com/v3/__https://ammrl.groups=
.io/g/main/message/2261__;!!PvDODwlR4mBZyAb0!RiEGtkbdiaZLzQEb6YOkgvEksPRMQ3=
k60TTgi9_uS5jpQ_XIVio862h8UTWsOY3qnBenR7IfrWBD36gtt_LIikWiQKxe$
Mute This Topic: https://urldefense.com/v3/__https://groups.io/mt/112337799=
/7559972__;!!PvDODwlR4mBZyAb0!RiEGtkbdiaZLzQEb6YOkgvEksPRMQ3k60TTgi9_uS5jpQ=
_XIVio862h8UTWsOY3qnBenR7IfrWBD36gtt_LIiu_eAIVa$
Group Owner: main+owner_at_ammrl.groups.io
-=-=-=-=-=-=-=-=-=-=-=-
Received on Tue Apr 22 2025 - 09:35:25 MST