Welding P-No. 45 to P-No. 8 Pipe Material - QC Concerns?

[Tferrari]

Could anyone please chime in on some of the considerations when welding P-No. 45 to P-No. 8 pipe material?

I would like to know a bit about the considerations for cracking, weld chemistry concerns, or other applicable QA/QC items to help control the welding process during field installation.

This material will be in low pressure service as part of a water treatment facility whose primary material is UNS S31803 Gr. 2205 duplex material (if you were wondering about the service conditions).

Thank you in advance.

 

[metengr]

Your main consideration for joining an austenitic stainless steel to a nickel-base alloy will be filler metal selection (Inconel filler metal) and monitoring interpass temperature during welding to ensure optimum corrosion resistance for the austenitic stainless steel. By the way, the duplex stainless steel, 2205 is considered a P-No 10H, Gr 1.

 

[Tferrari]

Metengr - thanks for your reply.

My comment with the Gr. 2205 material was just to give other members a flavor of the majority alloy for this particular facility and an indication of the corrosive service conditions.

The WPS I'm looking at lists the following filler metals for P-No. 8 to P-No 45: ERNiCrMo-4/ERNiCrMo-3, ERNiCr-3/ERNiCrMo-10.

This is not the particular WPS that will be used during site-installation, but it was the WPS used to fabricate the majority of the piping in the modules. I am just reviewing this in anticipation for what to expect when it comes time to install this equipment.

Would you have any other information you could pass along or any reference material you could direct me to?

Thanks.

 

[metengr]

I would suggest the articles below for dissimilar metal welds, which this combination falls under;

http://www.nickelinstitute.org/en/T...delinesforWeldingDissimilarMetals_14018_.aspx

http://www.imoa.info/_files/stainless_steel/IMOA_Shop_Sheet_104.pdf

https://mti.memberclicks.net/assets...- guides for dissimilar metal welding dmw.pdf

 

[stanweld]

What P45 alloy are you joining? Hastelloy G? Alloy 800? Alloy 825, Alloy 20? We have extensively used the ERNiCrMo-X fillers that you have listed.