P-22 to Carbon Dissimilar weld.
P-22 to Carbon Dissimilar weld.
(OP)
We have a dissimilar weld to make,P-22(2-1/4) to carbon steel.Suggested was to butter carbon with P-11(1-1/4) then weld to P-22.Is that correct?It sounded like a downgrade.If you qualified procedure could you weld P-22 direct to carbon.





RE: P-22 to Carbon Dissimilar weld.
Good day
Gerald Austin
Iuka, Mississippi
http://www.weldinginspectionsvcs.com
RE: P-22 to Carbon Dissimilar weld.
RE: P-22 to Carbon Dissimilar weld.
The client specs is finally binding but we need to understand if there is a technical reason for his asking for the buttering. If you qualify a PQR meeting all the spec requirements welding P22 to cs directly you would be within code but there are hardly any tests you would be carrying out for the creep properties, I don't exactly remember now, maybe tommorow I can reply exactly the reason for your clients asking for this buttering. There is a reason for that.
Thanks and regards
Sayee Prasad R
Ph: 0097143968906
Mob: 00971507682668
End of all knowledge is the attainment of immortality!
RE: P-22 to Carbon Dissimilar weld.
The problem is the PWHT. If the dissimilar weld is heattreated at the P22 required temperature you could impair the properties of the CS.
The solution would be : butter the P22 with P11 filler , PWHT , weld the CS to the P11 butter layer and PWHT at a lower temperature.
RE: P-22 to Carbon Dissimilar weld.
RE: P-22 to Carbon Dissimilar weld.
Buttering with CS or C-1/2 Mo , i.s.o. 1 1/4 Cr-1/2 Mo is not adviced because again the PWHT at P22 required temperature could impair the CS or C-1/2Mo filler metal properties.
RE: P-22 to Carbon Dissimilar weld.
Thanks and regards
Sayee Prasad R
Ph: 0097143968906
Mob: 00971507682668
End of all knowledge is the attainment of immortality!
RE: P-22 to Carbon Dissimilar weld.
As can be seen, one of the most important things for VAWELDER to know is what codes/specifications he is working to and what is allowed.
RE: P-22 to Carbon Dissimilar weld.
Preheat 400
Final PWHT 1250F 2 hours
Per ASME IX you need to have PQRs to cover your WPS so be careful.
In my opinion buttering is not necessary. WHat is the thickness? If you are working to B31.1 and the weld is less than .500 thick you can delete the PWHT requirement (if you qualify it that way)
Section 1 allows exemtion if less than 4" nominal diam, less than 5/8" thick and I think less than .15 carbon. hmm better check that out though(im quoting from memory) its in the material pwht charts some other factors too but its all in there.
Write back and tell us what the outcome was.....
Steve
RE: P-22 to Carbon Dissimilar weld.
RE: P-22 to Carbon Dissimilar weld.
Thanks and regards
Sayee Prasad R
Ph: 0097143968906
Mob: 00971507682668
End of all knowledge is the attainment of immortality!
RE: P-22 to Carbon Dissimilar weld.
This embrittlement is some how simulated in a step cooling test.
RE: P-22 to Carbon Dissimilar weld.
Thanks and regards
Sayee Prasad R
Ph: 0097143968906
Mob: 00971507682668
End of all knowledge is the attainment of immortality!