Liquid Nitrogen Filling Procedure
What You'll Need
- Liquid Nitrogen Tank, 100L capacity
- Pair of Heavy Gloves
- Two adjustable wrenches (at least 1" max)
- Swagelok adapter fitting
Procedure
- Take the 100L liquid nitrogen tank from the Ice and Nitrogen room on the 4th floor down to the two liquid nitrogen tanks in the loading dock
- Go to the sign-out list, and mark that you are taking 100L (or however much is needed) from the tanks, being sure to fill in the date, what you are taking it for (Instructional), and your name.
- Remove the dispenser faucet from the tank.
- Connect the short adapter fitting to the hose attached to the large Airgas tank.
- Connect the hose with adapter to the dispenser nozzle, tightening with your fingers and then with the wrench, until it is securely attached.
- Open and uncap the gas phase valve
- Open the dispenser valve
- Check one more time to make sure that all the valves are open and uncapped.
- Turn the dial of the liquid nitrogen container to "Open", allowing nitrogen to flow from the tanks into our smaller, more portable tank.
- Watch the amount that is in the liquid nitrogen tank.
- When it is as 100L (or close to it), shut off the dial of the main tank by twisting it clockwise, closing off the flow of liquid nitrogen into the tank.
- Close off the dispenser valve.
- Close off and cap the gas phase valve.
Use your wrenches to remove the connection between the tanks. There will be a small but non-dangerous pressure build up in the hose. Be ready for a little POP!
- Remove the adapter fitting from the hose.
- Reattach the dispenser faucet securely with the wrenches.
- Store the hose, and then bring the liquid nitrogen tank back upstairs.
Concerns
Always make sure that the gas phase valve is open and uncapped when you are filling the liquid nitrogen tank. Never stand in the path of the venting gas phase valve. That is sending out almost pure nitrogen. You will not know if you are breathing too much nitrogen, and unconsciousness could result. Always wear gloves when working with the liquid nitrogen. Closed-toe shoes and long sleeves are also required. Do not attempt to fill a liquid nitrogen container until you have been shown how.