×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Jobs

ASME VIII Div.1 Vs. Div.2

ASME VIII Div.1 Vs. Div.2

ASME VIII Div.1 Vs. Div.2

(OP)
Dear All,
I have to buy eleven air coolers in which the bundle is designed as per follow conditions:
-Design Pressure of 325 bars (g)
- Temperature design of 90°C
The material proposed, during the bid phase, from different Vendors is a Super Duplex Type 2507 in order to be in line with the process fluid chemical composition (recycle water with high chloride  content).
Considering the above case, I would like to ask you some questions:
1)    Could be better to design the Tube Bundle in accordance with ASME VIII Div.2 instead of Div.1?
In terms of headers thickness surely yes, but which are the negative side using the Div.2?
2)    Are there other header types which could be employed for this purpose, considering that the actual offers are based on plug and pipe types headers?
3)    Using a pipe type header can be the cleanness of tubes provided only if the bundle is one pass?
Any answer or other information on the matter would be greatly appreciated.
Thank you in advance,
Bye bye  
 

RE: ASME VIII Div.1 Vs. Div.2

Simdro,
The air cooler design code is API 661 / ISO 13706.
The reference pressure vessel code for the headers can be ASME VIII Div 2, but the design pressure / temperature doesn't justify that selection. For Super Duplex material you don't get the benefit of significant material cost saving. However, you are most likely spending a lot more on testing, inspection and certificates that you would spend on a bit of extra thickness. Do you want the U2 stamp also? Big money...I suggest you stick to Div 1 and let the various suppliers to compete against each other for the job, which will include their guarantees, instead of blaming any fault on your specification.
Cheers,
gr2vessels

RE: ASME VIII Div.1 Vs. Div.2

(OP)
Thank you for your reply gr2vessels.
I completely agree with you.

So Div.1 will be a "must" to design the bundles considering also that the equipments shall be U-Stamp!!!

Many thanks again...

RE: ASME VIII Div.1 Vs. Div.2

If I understand what you have written here correctly your design pressure is 325 bar g or approx. 4,713 psig.
If that is the case you need to look at Section VIII Div. 1 paragraph U-1(c)(2)(j). I think your design pressure has exceeded the limitations of division 1.

RE: ASME VIII Div.1 Vs. Div.2

(OP)
Hi Archimedex and thank you for reply.

You understood very well the design pressure is 325 bars (g) as I wrote on my thread.

Sincerely I did not look the Section VIII Div.1, anyway I do not agree with you on the limitations matter considering that I have already contacted several Air Cooler Manufacturers and many of them refused to quote the Equipment using Div.2 as a designed code.

Anyway I'm going to investigate about Div.1 hoping that you are in trouble more than me.

Many thanks again.

 

RE: ASME VIII Div.1 Vs. Div.2

Yes - the limitation there is 3000 psig = 206.8 barg, however, read the whole paragraph through.

Let the suppliers provide design of the headers, welded header boxes would be fine I believe, but some migh opt for billet-type headers.

 

RE: ASME VIII Div.1 Vs. Div.2

(OP)
Ok Thermmech let me read the whole para of ASME so that I will be able to reply you.

Could you help to find some technical information concerning the billet-type header?

Your feed back would be greatly appreciated.
Thanks in advance...bye  

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!


Resources