Problem Solving Forum
September 16 - September 20, 2019
What factors would justify coating stainless steel in water or wastewater service? What standards and methods apply?
Nicole de Varennes of IRISNDT on
September 17, 2019:
I've been a bit confused about this myself, as typ ...read more I've been a bit confused about this myself, as typically the process for material selection, in order of mild to aggressive conditions, would be as follows: carbon steel, coated carbon steel, stainless, high alloys (with rubber linings and fiberglass where applicable). If the stainless is not suitable for the service conditions, I don't see why, with the extra cost, it would be the material selected. I do agree that isolating stainless from dissimilar metals is required. But coating stainless for corrosion resistance does not make sense to me.
Jeff Kim of Sherwin-Williams on
September 16, 2019:
You should coat SS if it will be exposed to severe ...read more You should coat SS if it will be exposed to severe immersion service. You should also coat SS to isolate from other types of metals to prevent galvanic corrosion. Other reasons like color-coding may dictate coating as well. Prepare SS for coating per SSPC-SP16.