Detrimental Effects of Carbon steel contamination

[apiguy]

Does anyone know where I could find some documentation of the detrimental effects of carbon steel contamination.

The problem is that a welding contractor has welded some old rusty re-bar to our brand new SA358 254SMO material. The new welds in the material are fully austenitic and have a high nickel content.

The manfacturer of the steel says that there may be problems at the grain boundaries.

Any suggestions......... Richard Schram
Mechanical Integrity Specialist
Pharmacia Global Supply Arecibo-P. Rico
rschram@pharmacia.com

 

[joescan]

This guy will be able to help

http://www.azom.com/experts.asp?iExpertID=68

 

[rustbuster1]

You can't be serious!
If the 254SMO has been specified here to obtain its excellent resistance to pitting and crevice corrosion, it is in dire peril if carbon steel rebar is welded to it or if the surface will be covered with rust deposits from corrosion of iron contamination.
Maybe you don't need the 254SMO in the first place?? There's a ton of information on this and how harmful it can be - depending on the environment - at the NiDi web site at

http://www.nidi.org

 

[apiguy]

Rustbuster1,

If you only knew what I go through on a normal day here. Lot's of things to throw a wrench in the works daily. It really keeps an inspector on his toes......wouldn't trade it for nothin'! Richard Schram
Mechanical Integrity Specialist
Pharmacia Global Supply Arecibo-P. Rico
rschram@pharmacia.com

 

[mcguire]

Richard
Any carbon steel in contact with the stainless surface will destroy the protective film at the point of contact and render it un-stainless. To estimate how bad the damage is in your case, approximate the iron contamination to an equivalent concentration of ferris chloride at the same temperature. This is a relatively easy corrosive medium to look up data on and will be worse than your iron contamination, so you get a little safety factor.

 

[apiguy]

Thanks guys,

I was needing some printed information to give to a contractor as "proof" he had to perform additional work that was not in his original bid. I now have quite a bit of information to justify my request.. Richard Schram
Mechanical Integrity Specialist
Pharmacia Global Supply Arecibo-P. Rico
rschram@pharmacia.com