Metal finishing Q&As since 1989

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How thick should powder coating be for pad-mounted transformers?

We are specifying pad mounted Power Transformers for shipyard applications on the Gulf of Mexico. The go by specification we have calls for: All ferrous metal surfaces shall be thoroughly cleaned after fabrication and given a chemical rust inhibitive treatment. An iron phosphate coating shall be applied to enhance adhesion of the powder paint. After all surface preparation is completed, the equipment shall be dried of all remaining liquids before the paint is applied. A polyester powder paint shall be applied to a thickness of 1.5-2.0 mils. After application is completed, the equipment shall be cured in a curing oven for a time and temperature as required by the paint manufacturer to liquefy the powder and bond the paint to the iron phosphate coating. The Transformer shall then be coated with a two-part catalyzed urethane enamel with 1 mil nominal dry thickness. Is this adequate?

Charles Aeby
Engineering of ship yard systems - Charlotte, North Carolina
2003

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Can you give any indication of the dimension of fins to be applied to casing of transformer? Or do you use radiators for cooling?

Dr. Norbert Seyfert
surface development - Olpe, Germany
2003