We have been having some instability in our dewar pressure and siphon temp
on our Prodigy probe. It was recommended that we empty our LN2 dewar and
check for ice blockages.
Hoping for some quick advice. There is definitely ice inside the Dewar,
and some black oily looking crap on the bottom AND a broken silicone tube
lying on the bottom. I assume the silicone tube once connected to the fill
port dip tube. The only way to remove it is to take the top assembly off
the dewar and clip the wire that says Do Not Ever Remove. I'm trying to
dry it out by flushing it with ethanol because it will take days for the
Dewar to warm otherwise. I've been able to get most of the ice out, but
it's not removing the black oily looking crap on the bottom. There may
also be a screw or clip down there that held the silicone tube on, but it's
really difficult to see.
Any other safe drying solvents? Acetone? Methanol?
Can I take the top assembly off the Dewar?
Any other suggestions? How best to fully dry this of all solvents before
refilling with LN2?
Best
--
Ken Sharp-Knott
Department of Chemistry
NMR Facility Manager
Virginia Tech
(540)267-6502 (Cell)
(540)231-0885 (Office)
Received on Sat Aug 14 2021 - 06:01:20 MST