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Corrosion in SS304 tank used for potassium permanganate solution

2007

I am a process engineer working in a Fasteners industry. We are using potassium permanganate ⇦this on eBay or Amazon [affil links] and sodium hydroxide solution for descaling of fasteners. We are using SS 304 material for constructing the tank. I am noticing corrosion as taken place at the bottom of the tanks as tiny holes. This is happening only at the bottom and not the side walls. I am maintaining a temperature of 75 °C.

Can anyone give me suggestions for overcome the above issue.

Thanks in advance,

B.K. Nair
process engineer - Cochin, Kerala, India

How are you heating the tank?

James Watts
- Navarre, Florida
2007

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2007

Pit corrosion is characteristic of anodic side of a corrosion cell.

Try grounding the entire tank, and/or look for possible stray currents such as something attached to or contacting the tank that is connected to or close to a source of electric current. If found, insulate it from the tank. Or remove it. Lok for steel rake leaning on the tank, etc.

Don Baudrand
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [on Amazon or AbeBooks affil links]
           and "Plating ABS Plastics" [on Amazon or eBay or AbeBooks affil links])

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2007

I have had a Stainless tank containing an anodising dye perforated on the bottom.
The cause was attributed to dropped parts (probably brass) setting up a galvanic corrosion cell.

Geoff Smith
Hampshire, England