Stainless corrosion
Stainless corrosion
(OP)
I have a solid "stem" made from 316 stainless. The part has almost been eaten away from the inside (again, it's not hollow). It's used in commercial water application. What could attack the steel that badly? Elemental analysis does show a small % of sulphur (0.3 - 3.0 depending on the specific spot). I have not been told the time frame this was in service.





RE: Stainless corrosion
Could you post a picture of the stem?
Could you post the conditions that the stem sees?
RE: Stainless corrosion
RE: Stainless corrosion
I would suggest you Google MIC damage in stainless steel for more information and conditions that can cause this damage.
RE: Stainless corrosion
Another possibility if the water has high chlorides and the stem sat there under stagnant conditions it could literally dissolve, as in your case.
Try to get the properties of the water so a little analysis of your problem could be made and suggestions to mitigate same.
In the mean time I would not go back with SS under the same conditions as seen by this part.
RE: Stainless corrosion
There have only been 2 failures in 2 years like this though. I have no idea what the number in service are. Any idea why one may be more susceptible than another of the "same" composition?
RE: Stainless corrosion
This is crevice corrosion, doesn't really matter if it was driven by microbes, simple Cl level (doubt it), or some funky water additive.
Water temperature, conductivity, oxygen content, tight crevices, lots of food for microbes.... this list could go on. A few small changes in the environment and I can change the corrosion rate by 1000x.
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Plymouth Tube
RE: Stainless corrosion
RE: Stainless corrosion