Hi,
Has any one out there had any problems (or heard of any), welding Inconel 82 filler, onto 2.25/1.0 CrMo - as a cladding. Specifically cracking at the fusion zone between the two. We have welded 6mm of Inconel 82 by SAW strip, onto a CrMo tubesheet, which was inspected before shipment, after 2 weeks it was inspected again at the clients shop and found to be cracked along the boundary between the 2 alloys.
Any bright ideas would be helpful.
No bright ideas here. I have only GTAW the Inconel to P-5 mat'l as an overlay, and never had any problems.
Have you qualified the procedure as a corrosion resistant overlay? How may passes are required for the SAW strip to complete the 6mm overlay? What base metal preheat / postheat did you use?
Hi,
My client has qualified the WPS with the correct Pre heat and PWHT (as per code). There are 2-3 passes to be completed on the job which will be very carefully monitored during fabrication. The 6mm is the finished,machined thickness so they may put up to 10mm on.
Acess Special Metals Co.'s site. They're the manufacturers and owners of the brand "Inconel" and of course know their product better than anybody else.
You'll find plenty of information at
www.specialmetals.com/documents/joining
If the information contained there is insufficient, you can always give them a call and ask personally.
Giovanni S. Crisi
Sao Paulo - Brazil
Hi,
Thanks for that, I'm about to call their UK welding engineer and see if he can help
I'm thinking along the same lines as Bill. What is the tubesheet thickness and what preheat temperature was used for the welding? It is also possible to get "ductility dip cracking" in the Alloy 82 dilution zone due to low melting point elements (phosphorous and sulfer) in the base metal. Look at base metal chemistry for P and S content, calculate the dilution level based on average depth of cladding penetration into tubesheet divided by thickness from cladding surface to fusion line (or run chemical analysis on a cladding deposit sample removed from the cracked area and compare to chemistry for the bare strip material).
Hi,
The previous unit (on which the cracking problems were evident) was "supposed to" to be welded with 200C preheat and ASME Code PWHT.
It is possible that it wasn't.. So we will take on board your advice and also make sure that the next job is tightly supervised. The tubesheet is 250mm thick.
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