MONEL 400 to SS304 Welding 1

[ak1965]

We need to weld a 1/2" Monel-400 piping with a 1/2" SS-304 Valve.

Can some one suggest proper filler wire or a WPS to carry out this Butt weld joint.

Service temperature is 35 Deg C. & service pressure is 300 kg/cm.2

 

[rustbuster]

I would use ENiCrFe2 (Inconel 182) and ENiCrFe-2 (Inco-A)

 

[ak1965]

Thanks Rustbuster


While using Inconel 182, will its higher iron content cause dilution problem in weld pool?

I mean SS 304 and Monel has diffrence of Fe content!

Please comment.

 

[MikeMet]

Special Metals own literature recommend using Inco 82 or Inco 625. I would prefer the Inco 625 which also has higher strength that Inco 82

 

[stanweld]

ak1965,
I think you are confusing the iron dilution problem when using E/ERNiCu-7 alloy weld filler metal when diluted with iron from the 304 ss.

 

[ak1965]

stanweld


I did not confuse rather wished to clarify as there is a difference of Fe contents in SS304 and Monel 400.

 

[stanweld]

Iron dilution is not a factor when welding the dissimilar alloys with the filler metals recommended above.

 

[tab1999]

Seems like I remember some cracking issues from joining Monel to 304 in pipe welds?

" There is no Shortcut to anyplace worth going "

 

[stanweld]

tab1999;

Hot cracking is a very real possibility when welding with Monel welding filler metal. Even when welding with appropriate Nickel base filler metals or Nickel filler metals. hot cracking in the Monel HAZ can be a problem due to the large liquidus to solidus temperature range of Monel (even when properly cleaned).

Cracking in the HAZ of Monel castings is a greater possibility. Depending on the melting practice used for the Monel casting it may prove unweldable.