Galvanic Corrosion
Galvanic Corrosion
(OP)
For one of the Offshore project, in the skid packages, there are Instrument Junction boxed ( stainless steel) fixed to the skid structure which is of Carbon steel but painted with a coating system as below
Inorganic Zinc silicate ( primer ) for 150 microns + Epoxy High build polyamide with micaceous iron oxide for 75 microns + Acrylic polyurethance Gloss for 60 micros .
Client is asking the contractor that since the Stainless steel junction boxes is fixed to the CS painted structure, due to marine atmosphere, galvanic corrosion is bound to take place and hence suggesting to provide teflon inserts between these two parts..
Whether the above scenario is likely possible even if there is a painting system in place on the Carbon steel structure?
Thanks to clarify
Inorganic Zinc silicate ( primer ) for 150 microns + Epoxy High build polyamide with micaceous iron oxide for 75 microns + Acrylic polyurethance Gloss for 60 micros .
Client is asking the contractor that since the Stainless steel junction boxes is fixed to the CS painted structure, due to marine atmosphere, galvanic corrosion is bound to take place and hence suggesting to provide teflon inserts between these two parts..
Whether the above scenario is likely possible even if there is a painting system in place on the Carbon steel structure?
Thanks to clarify





RE: Galvanic Corrosion
Steve Jones
Corrosion Management Consultant
http://www.linkedin.com/pub/8/83b/b04
All answers are personal opinions only and are in no way connected with any employer.
RE: Galvanic Corrosion
When tightening a nut/washer in contact with a painted surface it is quite easy to damage the coating. The friction between the washer and the coated part surface created when the nut is tightened will easily shear even the toughest paint or primer.