Dear All
I am experiencing a problem when filling nitrogen into our Oxford 800 pumped
magnet, which has been in operation for over 21 years.
Recently, the boil-off pressure has been significantly higher than in previous
years, while the filling rate has decreased. This suggests that there may be
an ice blockage somewhere in the vent port line.
I am considering whether it is safe to use dry nitrogen gas to gently purge
the vent line in order to sublimate the ice or push out any loosened blockage.
However, I am concerned that this approach could potentially worsen the
situation if melted or dislodged ice is pushed back into the nitrogen vessel
and blocks the vent port further.
I would greatly appreciate any advice or shared experience on how to safely
diagnose and remove a possible ice blockage in the vent line.
Thank you very much for your assistance.
Best,
Tianzhi
-------------------------------------------------------------------
Tianzhi Wang, Ph. D.
NMR Manager
Sealy center for Structural Biology & Molecular Biophysics
University of Texas Medical Branch,
301 University Bvld, NMR dockside building, Rom 1.104
Galveston, TX 77555-1157
Email: tiawang_at_utmb.edu
(409)7476821 (O)
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Received on Fri Apr 03 2026 - 11:58:07 MST