Smart questions
Smart answers
Smart people
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Member Login




Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • 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.
Jobs from Indeed

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.

gpape (Mechanical) (OP)
1 Jun 05 15:10
Does anyone have any comments or history with these materials used for large, thick (14") ASME tube sheets?  Design 350 PSI @ 500°F - MDMT (-)20°F? I am interested in the toughness and the best material I can get.
Helpful Member!  metengr (Materials)
1 Jun 05 15:26
We have SA 350 LF2 forgings for our older high pressure and low pressure feedwater heater tubesheets. No problems to speak of - it is a very common forging material.

Today, I would probably recommend going with SA-765 Grade II only because it applies directly to carbon and low alloy steel forgings for use in heat exchanger and feedwater heater components, like tubesheets.
stanweld (Materials)
1 Jun 05 15:57
SA-350 LF1 and LF2 has a long history in both the petrochemical and power industries in similar thickness and thicker tubesheet applications. The primary differences between the two specs are SA-350 LF2 is made to fine grain melting practice and impact testing is required while fine grain melting and impact testing is optional for SA-765. There is also a subtle difference in impact test location for your thickness.
metengr (Materials)
1 Jun 05 16:11
Stanweld;
Impact tests are required in ASME SA 765 - Table 3. The purchaser can recommend other test temperatures as optional but you need to conduct impact tests. For Grade II the impact test requirement is 12 ft-lbs at -50 deg F.

gpape (Mechanical) (OP)
1 Jun 05 16:28
Thanks metengr!  You have stated the same evidence that I had originally come up with. The only draw back that I can see, is the addition of Ni, Cr, Mo, V, Al & Cu to the chemical analysis. I do understand that this makes it tougher and more weldable that LF2. I also am happy with the required testing, since I have required even more tests than SA 765 requires when I bought SA 350 LF2.
stanweld (Materials)
1 Jun 05 16:48
metengr,
Oops, misread 6.1. Going senile.
metengr (Materials)
1 Jun 05 16:54
Stan;
Been there and have done that many times. Time for a beer!
unclesyd (Materials)
1 Jun 05 17:52
stanweld

I call that a "senior moment" and it seems to happening more frequently.

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