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Coating/painting corroded conduit in underground spaces

I'm putting together a contract to clean up the corrosion and calcium deposits that have built up on exposed grs conduits and metal sprinkler piping that is located in some underground spaces.

The corrosion and calcium deposits are a result of water leaking and running down the walls and over the exposed conduits, etc. Often the corrosion occurs where the conduit stubs out of the concrete wall/floor.

I'm wondering what kind of products would be easy to apply, adhere to both grs conduits, metal piping and concrete - and can provide protection from future corrosion.

Thanks, Mike

Mike C [last name deleted for privacy by Editor]
engineering - Seattle, Washington, USA
2003

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Hi. Calcium deposits can be removed with products made for the purpose like Lime-Away or CLR ⇦ on eBay or Amazon [affil link] . I don't think that these mild acids would harm concrete or galvanized conduit and piping if used very judiciously. Diluted vinegar ⇦in bulk on eBay or Amazon [affil link] might work but is a bit aggressive.

If you wish to paint the galvanized runs, you will need to use a primer for the purpose.

because other paints will not stick to galvanized surfaces. Such primers ought to work on any bare steel as well. Top coat, but don't use alkyds as they saponify with galvanizing.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Ted is available for instant help
or longer-term assistance.
October 16, 2008

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