Coating, Painting, and Lining Materials

More metal surfaces are protected by coating, painting, and lining than by all other methods combined. Coatings, paintings, and linings that act as a protective film to isolate the substrate from the environment exist in a number of different forms. Therefore, the selection of a proper corrosion resistance system depends on a number of factors. 

Altering the environment provides a versatile means of reducing corrosion. Typical changes in medium thatare often employed in the petroleum industry are  

An inhibitor is a substance that, when added in small concentrations to an environment, decrease the corrosion rate considerably. To be fully effective all inhibitors are required to be present above a certain minimum concentration. 

Corrosion inhibitors can be divided into different categories. Among these, the most used class in the oil industry is film-forming. The effect of a film-forming inhibitor is to establish a molecular layer just on the steel surface and then a second hydrophobic layer of aliphatic tails. Therefore water cannot 

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