Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Nitrogen Dewer Leakage

Nitrogen Dewer Leakage

Nitrogen Dewer Leakage

We just stated using nitrogen in a selective soldering application a few months ago.
We have been getting dewar tanks that are roughly 5 feet high and 2 ft in diameter (3850 cubic feet I believe).
I have a few questions.
#1-Does the nitrogen naturally leak out of the tank when not in use? and if so where..
I know there is a pressure relief valve so I assumed it only leaks out when the pressure of the vent is exceeded..We did hear this once..scared the pants of anyone around..

We haven't gotten fully up to speed/tooled up,etc.. so there are times when it isn't used and is just sitting there for 2 weeks.
#2-Currently 1 big tank will be completely empty in 2 weeks of NO use. Does this seem right?

Our nitrogen supplier says thats normal but it just seems excessive to me.. 2 weeks and a large tank is totally empty when not even used??


RE: Nitrogen Dewer Leakage

Depends on how hot the tank gets (it's been warm in the eastern US lately, how's it been where you are?), how good the insulation is...but that is a fairly small dewar as industrial dewars go, so yeah, 2 weeks sounds about right.

If you aren't really ready to go with it yet, how about using a few K bottles, or even a cylinder trailer, for ready GN2 supply in the meantime?

RE: Nitrogen Dewer Leakage

tank/room is kept at 78 deg C constantly.
I'm just amazed it leaks out that quickly without getting used at all and without ever triggering the relief valve.

RE: Nitrogen Dewer Leakage

If it comes in a dewar, it's not leaking, it's boiling.

Mike Halloran
Pembroke Pines, FL, USA

RE: Nitrogen Dewer Leakage

78 C?!

That's pretty hot.  Might be worth considering a few more insulation blankets, though you may want to do the math (I think you are above the dimensions where critical insulation thickness needs to be considered, but don't recal off hand).

RE: Nitrogen Dewer Leakage

haha.. sorry been doing thermal testing in Celsius all week.. Room is 78 deg Fahrenheit.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close