Types of Anti Corrosion Coating

 This chapter covers general information about the main types of coatings currently available for use and the composition of coatings. It aims to provide basic information on coatings and is not a comprehensive guide to the selection of Anti Corrosion Coating. 

  • Products for application in new buildings and;

  • Friendly products for maintenance and repair, including both major renovations and on-board maintenance (OBM).

The types of Anti Corrosion Coating used for OBM are often single-pack products as this avoids difficulties in measuring and mixing two-pack products, although two-pack products are sometimes less available from paint manufacturers. Repairs made by service ship crews are rarely successful in the long run because of difficulties in producing sufficiently high quality surfaces. 


In general, paints are either targeted for specific vessel parts and specific functions for optimal performance, or universal coatings are available for all areas where performance is compromised. In all cases, there is a balance between cost, performance and maintenance. For example, Anti Corrosion Coating applied to the exterior of a home requires a different performance than the corrosion-resistant paints used in marine ballast tanks because the corrosion stress applied to the latter is higher. Ballast tanks are more difficult to maintain due to access difficulties and therefore it is preferable to use a highly effective (and often expensive) coating to keep the steel in good condition. 

Anti Corrosion Coating

Paint composition

Paint can be described as a liquid substance that can be applied or spread on a solid surface on which it then dries or hardens to form a continuous, sticky, film. Paints basically consist of three major components and numerous derivatives that are included in small quantities. The main components are: 

  • Binder (also called vehicle, medium, resin, film or polymer)

  • Pigment and expander

  • Solvent

Only the first two of these make the final dry paint film. The solvent is only necessary for the use of paint and to help in the formation of the initial film, but not necessarily, some solvent is always 

put into practice depending on the level of ventilation.

Binders

Binders are the film-forming components of paint that determine the main properties of the coating, both physical and chemical. Paints are usually named after their binder components (e.g. epoxy paints, chlorinated rubber paints, alkyd paints, etc.). The binder forms a permanently intact film that is responsible for sticking to the surface and which contributes to the overall resistance of the coating to the environment. Binders used in the manufacture of paints fall into two classes, thermosets and thermoplastics. Once dry the thermoset coating will be chemically different from the paint in the can. Thermoset coatings are not affected by solvents once cured. 


With a thermoplastic coating, dry film and wet paint differ only in solvent content and chemically, they remain essentially the same. If the solvent originally used is coated with a thermoplastic coating, it will soften and dissolve again in that solvent.

Cross-linked (thermo set) coating

These coatings are usually supplied in two separate packs that are assembled immediately before application. In liquid paints where solvent is included, drying is considered a two-stage process. The two phases actually come together but at different rates. 


Stage 1: Evaporation removes the solvent from the film and dries the film touch. 

Stage 2: One of the following four methods, the film gradually becomes more chemically complex:

  • Reaction with oxygen in the atmosphere, called oxidation.

  • Reaction with added chemical treatment agents.

  • Reaction with water (atmospheric moisture).

  • Artificial heating.

This change in paint is known as drawing or curing. The films formed by the above methods are chemically different from the original binders and will not re-dissolve in their original solvent. These resins are especially important and their use as a binder was one of the most important advances in Anti Corrosion Coating technology.


The corrosion resistance coating prevents metal parts from damage due to humidity, salt spray, oxidation, or exposure to a range of environmental or industrial chemicals. Anti-corrosion coating provides additional metal surface protection, which serves as a barrier to prevent interaction between chemical compounds or corrosive materials. These also have an abrasion resistance bonus, non-stick efficiency, and chemical protection. This coating provides a high level of corrosion protection for industrial parts which operate in extremely corrosive environments. More information about  then Visit - http://www.protexion.in/anticorrosion-protective-coatings.php 



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