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High Emissivity, Corrosion resistant coating

I need to coat a transformer enclosure. The enclosure will be constructed of approximately 22 ga sheet steel. UL requires a corrosive resistant finish. The industry currently uses Galvanized plating to achieve the non-corrosive property, but what I have found is that the emissivity of the Galvanized finish is terrible, overheating the transformers.

The enclosure in question sells for less than $10.00, so the coating should be in line, relative to the cost /resale.

Ideally the coating would be applied prior to the bending process, so durability is preferred, but not critial as the box is a behind the scenes component. A spraying of the coating post bending, though not ideal, may be acceptable.

Thank you very much for any help you may be able to offer.

Regards,

Steve Towne
AMS Company - Riverside, RI
2004

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2004

Pre-painted coil is indeed an inexpensive solution, Steve, but the corrosion resistance will not even begin to compare with galvanizing. Is this for interior or exterior exposure?

More expensive, but perhaps ideal, would be to make the enclosure from pre-galvanized, prepainted coil.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Ted, The exposure is indoors and outdoors, prepainted galv sheet may work, but what about the emissivity, would it be very good?

Steve Towne
- Riverside, RI
2004

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I'm not the right guy to ask since I haven't worked with that parameter since school, which was a long time ago. But a quick 15 minute refresher leads me to believe that the surface emissivity depends on the material of the surface rather than the galvanizing that lies behind it.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004