Welding 9% Cr to 310s SS

[QAScott]

Hello,

I am looking for the filler metal for welding 9%Cr to 310s SS with GTAW and SMAW. The P-No. is P5B to P8. The joint will be Single Vee Groove open root.

Thanks,
QAScott

 

[Koz]

Hi QAScott,

Can you give us an ASTM spec on the 9% Cr so we can see what else is in there?
Koz

 

[kramg]

Hi
It does not really matter if this is standard 9CrMo or 9CrMo modified (P91). The power generation industry has many years of experience with dissimilar joints and have used nickel based consumables ie AWS A5.11 ENiCrFe-3 SMAW, AWS A5.14 ERNiCr-3 GTAW.

As 310 is fully austenitic there will be no problems undergoing the post weld heat treatment for the 9Cr material.

Hope that this of use

 

[unclesyd]

Koz,

ASTM SA387 G91 Cl2 U

P5B

 

[QAScott]

Thanks to everyone for the help.

Scott

 

[stanweld]

With the filler metals specified by kramg, you may wish to butter the P-5B material, PWHT then make the joint between the buttered P-5B and the type 310 SS again using the same filler metals. Buttering depth after machining should be 3/16" (5 mm).

 

[aybee]

QAScott , take care when welding P91 , there is a lot of good stuff in the other replies but remember that despite many years of being welded its not an easy material to weld . buttering is a good idea, also PWHT @1400F after buttering and the final weld.
refer to ASME SFA 5.01 for consumables dont assume that the inconel consumables are ok they can be embrittled at the PWHT. EPRI have prepared a document Guideline for Welding P(T)91 materials ..it runs to about 30pages it covers welding to ss but not 310 so I would do a lot of asking around and procedures before I jumped into the real weld
"P(T)91 should not be treated as just another CrMo steel" quote EPRI..good luck