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Corrosion Preventing Paper for Ferrous Castings in Salt Water?

I want to ship cast iron, cast steel and machined steel parts overseas. The parts will be at sea for 5 weeks, exposed to salt water fumes during this time. The parts will then be stored for 2 months before use. Some parts will be painted after storage. I am thinking of wrapping the parts with a corrosion resistant paper to protect these parts from corrosion. The product is a single layer 'kraft' type paper impregnated with a nirite-based corrosion inhibitor. According to the paper manufacturers' literature, the corrosion preventing agent migrates from the paper to the part, putting down a protective layer on the surface. It is claimed that the paper will protect all surfaces, including recessed areas. I have no experience with this product. Can anybody comment on the potential for using this product in the conditions described? Are there any standards/test results for corrosion resistant paper wrap? Thank you.

Thomas Kemp

2006

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2006

What you're describing is a "volatile corrosion inhibitor". These things have been around for a long time and are absolutely proven to work... within limitations. As long as the part is tightly wrapped, has no cavities above a certain size / volume, and the entire package stays dry everything is fine.

You'll want to involve a packaging engineer with this project to keep from losing your shirt on corrosion claims. you need to know how big the cavities are, how much surface area is depending on the vapor phase of the inhibitor, and you'll need to be sure the over-packing is secure.

Jeff Watson
- Pearland, Texas

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V C I Plastic bags are a much better option as they offer corrosion protection from both sides of the bag surface, compared to the paper that can be used only on the inside surface.We use these regularly to ship parts overseas where transit times are more than 5 - 6 weeks. They offer the most cost efficient corrosion protection and are also versatile as it is available in sheet form ; plastic tubing rolls and custom made bags to fit all sizes and shapes.

Kiran Patel

2006