NMR Folks,
New 500 and 600 systems are being installed here. Two weeks after the magnets were energized and were stabilizing, the nitrogen and helium flow rates for the 600 magnet increased dramatically (off scale) and substantial ice formed on the fins at the nitrogen exit port. This followed an apparently routine LN2 fill.
More troubling is the frost that also formed down in the center bore. It did not form at a single point but more concentrically.
The console installation engineer is now here. He observed another LN2 fill. Near the end of the fill, a "burp" sound emanated from the magnet. He said he had never heard that before.
Has anyone else ever observed frost in the bore like described above?
Has anyone had a magnet that was anything but mute?
Thanks in advance for you comments and advice!
Ed Waali
Department of Chemistry
University of Montana
Missoula, MT 59812
Received on Thu Aug 03 2006 - 10:36:20 MST