Liquid nitrogen dewar question

jdm61

jdm61

itinerant metal pounder
Joined
Aug 12, 2005
Messages
47,357
What kind of dewar do you need for cryo and what kind of rack/holder do you need to use?
 
You need a dewar that is rated for LN,The main thing is neck size,my 25 litre dewar has a 1-3/4" neck opening whick is fine for me as I don't do any huge knives.The smaller the neck the longer the LN will last.
I got mine off flea bay,I get it filled at my local welding supply.Half a tank costs me 30 bucks and lasts about 5-6 weeks.
As for a rack,I get 1/16" SS welding rod when I get my Ln and just suspend the blades with the rod,made a loop in one end and just hang it on the side.

Stan
 
Thatnks, Stan. I notice that the narrow neck ones seem to be designed for storing LN for longer periods of time, whereas the ones with the wider necks seem to be more for transporting things like bio samples. Do most of the dewars have the foam plug that allows you to run wire hangers up around the mouth of the bottle?
 
Yes Sir,the all have the foam plugs in the tops as they have to be able to off gas the LN,If they were sealed tight the would explode.

Stan
 
The second question I have is how do you tell how tall the internal "chamber" is? From what I can tell, once you get above the very small dewars in the 1-4 liter range, the standard cow spooge vial holder or dipper is 11 inches tall. At that as long a piece as you can fit into these containers? I have a few designs for knives that would need cryo and one of them has an overall length of around 11.5 inches and is about 2.25 wide, so I have to look at the dewars that have a larger mouth than the somewhat standard 2 inch.
 
You must log in or register to reply here.
Back
Top