Paint is the most commonly used coating. Paint systems usually consist of primer, intermediate coat, and finish coat.
Primers: The primer is applied directly onto the cleaned steel surface. Its purpose is to wet the surface and to provide good adhesion for subsequently applied coats with corrosion inhibition.
Intermediate coat: Intermediate coat is applied to increase the total film thickness of the system. The thicker coating, the longer life.
Finish coat: The finish coat provides the required appearance and surface resistance of the system. Depending on the conditions of exposure, it must also provide the first line of defence against weather and sunlight, open exposure, and condensation.