Background
The building that this NMR facility is housed in is over 40 years old and has only 1 elevator. Recently, that elevator died in a non-repairable fashion. New, custom parts are being fabricated to rebuild it, but the elevator will be down for over a month.
The NMR facility is in the basement, and there are no windows or other access to the ground floor besides stairs.
The first week, we bumped a liquid nitrogen dewar down the stairs. This required several large, strong helpers, none of whom wanted to do it again.
The safety officer rejected the suggestion of running a rubber hose down the steps.
The solution is to purchase a 30 foot long cryoline, and run it through a hole in the facility ceiling. Once cooled down, the line transfers pretty efficiently. We estimate that we are only losing 20% or so above normal. This is helped by storing the line in a -80 freezer overnight before use. We run liquid turning to gas nitrogen through the line until liquid comes out. Then we stop the transfer, insert the line into the magnet or dewar, and turn it back on. This way, we are not blowing liquid out of the magnets. This also clears out the line.
Some pictures:
This shows the hole in the ceiling. The dewar is sitting in the research lab above.
This shows the hose coming down and going across the lab.
This looks back at the hatch and the widebore 300. Yes, the hose is non-magnetic. We checked before getting the hose close to the magnet.
Looking across the lab to a dewar fill.
We didn't want the hose just dangling from the magnet, so we draped it across a chair and a ladder.