Weld overlay for steam corrosion
Weld overlay for steam corrosion
(OP)
Dear Experts,
We have a carbon steel "Tee" joint in steam service experiencing rapid metal loss. We suspect FAC. I did some research on this forum and found P11 or P22 would be a good substitute to reduce the metal loss. Somebody in our group suggesting weld overlay. I am looking for some advice if it will work? Thanks.
We have a carbon steel "Tee" joint in steam service experiencing rapid metal loss. We suspect FAC. I did some research on this forum and found P11 or P22 would be a good substitute to reduce the metal loss. Somebody in our group suggesting weld overlay. I am looking for some advice if it will work? Thanks.





RE: Weld overlay for steam corrosion
The problem with weld overlay is that you will be chasing the FAC damage around the Tee section. The weld overlay with 1.25% Cr-1/2% Mo could be used as a short term fix. Ultimately you will be chasing the FAC damage to another location on the Tee.
RE: Weld overlay for steam corrosion
But don't delay, this is how people get killed. And now you know that there is a risk.
If you weld overlay continue the overlay well beyond the last visible point of attack. Per Metengr's caution, you will just move the erosion down stream. If the length through the T that shows damage is 24" long you need to go at least that far beyond the area.
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Plymouth Tube
RE: Weld overlay for steam corrosion
RE: Weld overlay for steam corrosion
2. You need to go well beyond the areas of obvious attack.
A. You need to protect the areas where the attack is slower and not obvious yet.
B. The transition from the overlay to the regular will cause some local turbulence which might lead to some localized attack.
This will be an ongoing inspection issue. You need to be prepared for that.
Replacing the T is the best route.
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Plymouth Tube