Stellite 6 and buttering layer - requirements

[kclim]

We're looking at performing a weld repair on a valve seat. Valve body is a Cr-Mo material. Proposed method of repair is to remove damaged Stellite 6 layer and buttering (Inconel 625) layer, and reapply buttering layer and Stellite 6.

Was wondering what the requirements for the buttering layer were, in particular how thick it needs to be. Is the thickness dictated by a maximum dilution requirement, or is there a standard thickness for a buttering layer?

Thanks

 

[metengr]

kclim;
For the Inconel butter, I would use 1/8" max deposit thickness. This is our standard to ensure adequate buffer for the Stellite 6, and we never had a problem.

 

[kclim]

metengr, thanks for your reply.

Should that read 1/8" min, rather than 1/8" max? I would've thought thinner buffer layers give rise to more problems (dilution). Also note in ASME IX QW 283 (welds with butter) that going below 3/16" buttering layer thickness, heat input (QW 409.1) becomes an essential variable. Wouldn't this complicate things?

 

[metengr]

kclim;
Sorry about the typo, you are correct, that should read 1/8" minimum. Too much travel...........