Cryo Tour

Cryo is where is spend most of my time here, so I thought I’d give a bit of tour of the place. The Cryo facility is about a 2-5 minute walk from the elevated station, depending on weather, and is the closest building, after the heavy machine shop/ vehicle maintenance facility.

Cryo is the grey part of the building. The wood attachment is the Balloon Infaltion Facility, or BIF, which is used by Meteorology and NOAA. You can see the big silver doors to the right, where the balloons are brought outside after being filled with helium from my part of the building.

The first thing to do when walking into cryo is to tag in. This is a safety thing, so that if there is an accident that requires one of the emergency response teams, they know how many people are inside. 

There are similar boards at many of the facilities on station. After getting tagged in, stop by the cryo office, right next to the board. 

Then on to the important parts of the cryo facility, the three bays that contain almost all of the cryo equipment.

The liquid nitrogen plant (white), storage tank (steel),  transfer dewar (grey)

Liquid nitrogen (LN) is used for a couple of different things on station. The main use is in the liquid nitrogen cold trap I use to condense gaseous helium into the liquid heium dewars. It is also used by Aurora, a small camera which observers aurora (which I’m sure comes as a big surprise. They use it to keep the viewing window clear of frost. Occasionally medical will also request a small amount of liquid nitrogen. There is also the possibility of using some LN for burgers and ice cream.

The room with the LN plant also contains an assortment of LN and He dewars, as well as a lot of spare parts and tools.

The next bay over is almost completely occupied by the three liquid helium dewars, Alvin, Simon, and Theodore. It also contains the compressors that run the cold-heads, which maintain temperatures of ~4K inside the dewars.

Simon, Theo and Alvin

Simon, Theo and Alvin's compressors (grey), sitting on top of a couple of chillers,
which are an emergency back-up. 

The last bay in the cryo facility contains the gaseous helium half-rack tanks.

12 tanks of gaseous helium. The top of the rack is useful for storing things like a
sail, a TV/VCR, and lots of extra LN transfer dewars

Most years the back-bay also contains two huge liquid helium transfer dewars, from which helium would be transferred into Alvin, Simon, and Theo throughout the winter. This year we don’t have them, so I set up an unused fuel bladder to capture the helium which is vented during dewar fills for BICEP2. So far it has worked quite well, and I’ve filled one of the half-rack tanks with recaptured helium.    

Hanging out on the bouncy castle after a fill.