Member Login

Remember Me
Forgot Password?
Join Us!

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!

Join Eng-Tips
*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.

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

Circulating Vents Vs Gas Blanketing

Circulating Vents Vs Gas Blanketing


I am new to the forum. As per Appendix H, Sec H.5.2.2 , API 650, 11th Edition, internal floating roof tanks require gas blanketing if there are no peripheral circulation vents on shell and a vent in the fixed roof.

For a greenfield project, what are the pros and cons of the both the cases. One when vents are provided and hence no gas blanketing. Other when vents are not provided but gas blanketing provided.


RE: Circulating Vents Vs Gas Blanketing

With vents, and a hydrocarbon in the tank, an occasional time with the headspace air / hydrocarbon vapor mix in the Explosive/Deflagration Burn range is unavoidable.  I REALLY don't like vents.

Look at an Argon blanket for the space above the floater.  N2 blankets require a continous 'whisper' purge, and use a lot of N2 in a years time.  Just dump 2 or 3 bottles of argon from the welding supply store on top of the roof.  It is about twice as heavy as air/oxygen, and will form a 'fixed' blanket between the floater and the air.  IIRC, there is 125 ft^3 in a single cylinder of Ar.

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