[3dem] issues with liquid nitrogen tanks

[Xu, Chen]

Hi Kristin,

it happened at our site. Even fairly new tanks can have this too.

We came up with a relatively simple solution - to use a 230PSI pressure tank to help the two LN2 supply tanks. There is no check valve at "vert" port of supply tank so we can help to maintain reliable ~20PSI using high pressure tank. We hook two supply tanks to the system (via a not long VP pipe). This way, both tanks have the same pressure. I attached a picture here.

-Chen

________________________________________
From: 3dem <3dem-bounces at ncmir.ucsd.edu> on behalf of Parent, Kristin <kparent at msu.edu>
Sent: Tuesday, January 28, 2020 2:45 PM
To: 3dem
Subject: [3dem] issues with liquid nitrogen tanks

Hello fellow 3dem-ers,

We are experiencing quite an annoying situation with Airgas and I am wondering if other folks have had similar problems and what potential solutions are.

We have a custom manifold from Chart to deliver liquid nitrogen to our Talos Arctica that can be equipped with two 240L tanks, each with 22 psi pressure. This should help reduce the LN2 waste and be more efficient, and when our tanks are good, it really is amazing. BUT, some of the time Airgas gives us tanks that we cannot use as the pressure never builds beyond 10 psi and we have to return full tanks. They are not the nicest about this either ☹

We know the manifold is working correctly, and that it is caused by individual bad tanks. Has anyone else had crappy tanks? Do people just buy their own tanks and have them refilled instead of swapped?

Unfortunately, in Michigan Airgas is our only option, so any help would be appreciated.

Thanks in advance,
Kristin

--
Kristin N. Parent, PhD
JK Billman, Jr., MD Endowed Research Professor
Director, MSU Cryo-EM
Associate Professor of Biochemistry and Microbiology
Michigan State University
603 Wilson Rd
East Lansing, MI 48824
Phone: 517-432-8434
https://kparentlab.natsci.msu.edu/<https://nam01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fkparentlab.natsci.msu.edu%2F&data=02%7C01%7CChen.Xu%40umassmed.edu%7Ccf9530c76e6b478db46c08d7a42a9f82%7Cee9155fe2da34378a6c44405faf57b2e%7C0%7C0%7C637158375294278224&sdata=AhGxLFX2WOEk906tF1H%2FFfbosRqsF93pkDSSF8e2lAY%3D&reserved=0>
Twitter: @Phage4Lyfe

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