Weld metal diluted

[GemmellG]

Using window weld to replace damaged tube. Tube is SA210A1 with inconel 625 overlay. When using the window weld technique the root pass is in reverse i.e. the back side of the root is on the exterior of the tube there is no access to argon purge so using I625 filler is not an option. Used ER70S-6 expecting to get dilution from the existing overlay. All the mechanical testing (tensile & bends) all passed. Conducted some hardness test on the root pass there are a couple of reading in the mid 300 brinnel I would expect this from the bimetallic dilution. Can any one comment if there is a concern.

 

[metengr]

There should be no concern regarding the conditions you described above. There is little one can do regarding dilution on the back side of a window weld repair.