×
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

Joining CrMo to CS
4

Joining CrMo to CS

Joining CrMo to CS

(OP)
We are joining Cabon Steel P1 material, A106 Gr Bto CrMo P5B, 9 Cr 1 Mo.  Should we use  E-XXXX-B2L or E-XXXX-B8 or E-7018-1 elctrode.  The operating temperature is 300 to 700 deg F.  The weld will be preheated to 350 F and PWHT at 1350F.  
What would be the affect of each of the electodes with the base metal as far as:
Oxidization
Creep
corossion etc.???

Which electrode is recommended??  Reason??

RE: Joining CrMo to CS

2
The operating temperature range you have stated should not result in any appreciable creep deformation for the Cr-Mo material, and for the carbon steel you are right at the transition to time dependent effects on strength properties (creep deformation).

Regarding your weld joint, I would suggest using a B3 filler metal for the dissimilar metal weld joint. I would increase your preheat to 400 deg F, and your PWHT temperature is too high. For P-No 5 B Grade 1 material, I would use a 1300 deg F PWHT, this is below the lower transition temperature for the P-No 1 material (CS).

RE: Joining CrMo to CS

Recently we had a same case and we used B6 electrode. Considering the high temperature services the resistance of filler metal is more than the base metal P1.
In case of using E7018 as carbon steel filler metal it can not work at high temperature considering the properties of weld metal comparing to base metal which is normally wrought steel.
It is recommended to use the higher material class for joining dissimilar metals.

RE: Joining CrMo to CS

banaeian;

Quote:

In case of using E7018 as carbon steel filler metal it can not work at high temperature considering the properties of weld metal comparing to base metal which is normally wrought steel.

This is not really an accurate statement. The strength of the weld joint is limited by the strength of either of the two base metals being joined provided a weld filler metal matches either of the two base materials. In this case for the stated operating temperature, even an E7018 filler metal would be suitable for this weld joint because it matches the CS base metal that is being joined.

RE: Joining CrMo to CS

Normaly I would use an austenitical electrode with
10%Ni,18%Cr, maybe with 1-3%Mn.
The only problem is that after welding, you must use controlled cooling time. This should be such long that to not to let form martensite in the t8/5 cooling periode. In these cases martensite is public enemy no.1. But for this there are standard diagramms and you can easily choose this cooling diagramm.

http://www.heavyplate.com/heavyplate/servlet/basis.Dispatcher?Masken_NR=7305&Session_ID=25ktjzmtUeN

Good luck!

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