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Epoxy Coating on Mild Steel food equipment is peeling

Is it potentially possible that the oil from a punching operation can penetrate deep into rolled mild steel, and thus affect the adhesion of the epoxy coating in the long run? The metal is cleaned with thinners prior to application, and a primer is applied. Samples undergo a MEK Rub Test, which was fine. A few weeks later, the coating started to peel from the lids. It is critical, because the equipment is used in the food industry.

Koos Gouws
Management Consultant - Somerset West, Western Cape, South Africa
January 14, 2008

Thinners are not adequate for removing oil as they will leave a very thin layer and your paint will peel. A vapor degreaser is better, but expensive to operate and maintain and prone to serious abuse and misuse. The best alternative is an alkaline cleaner formulated to remove the particular oil and dirt. It is best to have at least 3 counterflowing rinse tanks with the last one with DI water and heated to about 140 -160 F for rapid drying.

James Watts
- Navarre, Florida
January 16, 2008