Most Common Industrial Coating Types and Their Applications
Industrial coatings are critical to protecting different types of industrial coatings from mechanical, chemical, and environmental degradation. Without this protection, assets often start to break down or corrode or even become unsalvageable.
An industrial coating may be defined as a specialised capable of protecting various substrates. These coatings come with different physical and chemical properties such as corrosion resistance, protection from UV exposure, and more. However, it is important to note that no coating can provide all the protection required by a structure. This is why a comprehensive coating system usually comprises of one or more coating types to protect the substrate from all the physical, chemical, and galvanic factors. To choose the best-suited coating system for their service location, must understand different coatings types and how they can form a total protective coating system by working together.
Here, we will discuss the advantages as well as tradeoffs of common coating types such as polyurethanes, zinc-rich primers, epoxies, and others.
Epoxy Coatings:
The typical components of these coatings are an epoxy base and a curing agent. By manipulating these two components, it is possible to achieve a wide variety of coating properties. For example, phenolic epoxy coatings have excellent chemical resistance. On the other hand, epoxy polyamide coatings offer great resistance to moisture. As a result of this versatility, depending on the application requirements, epoxies are extremely effective as an intermediate coat, primer, or even a topcoat.
The most noteworthy limitation of epoxy coatings is their moderate to poor performance when exposed to sunlight. This is why epoxies are used mostly in submerged or interior applications.
Polyurethanes:
If abrasion resistance and durability are your key considerations, polyurethane coating can be a good option. Aliphatic polyurethanes are well-suited to exterior environments because they perform well in sunlight and provide excellent colour retention. However, aromatic polyurethanes tend to weather and chalk when exposed to sunlight. This is why they are used mostly in submerged conditions.
Though polyurethane is preferred for its versatility, it contains isocyanate (-NCO), which is a carcinogen. Also, this type of coating is more expensive compared to epoxies and its application requires protective equipment and skilled workers.
Inorganic and Organic Zinc-Rich:
Zinc-rich coatings contain high loadings of zinc dust and protect steel surfaces by providing galvanic protection. The coating itself gets corroded but protects the steel surface beneath it. Compared to organic zinc-rich coatings, the inorganic variant provides better abrasion resistance and galvanic protection. However, inorganic zinc-rich coatings require a lot more surface preparation. Both these variants adhere well to the steel surface and perform well when used as a multicoat system’s primer.
One serious drawback of zinc-rich coatings is their low resistance to alkali and acids. Also, in most applications, these coatings must have a topcoat.
Alkyd Coatings:
Though not as effective as epoxies and polyurethanes, alkyds have good damage resistance properties against moisture. By adjusting its components, it is possible to create custom coating systems capable of withstanding a variety of conditions. As this type of coating needs to be permeable to oxygen, it has a longer drying time compared to other coatings. The chemical curing reaction can be accelerated by applying heat.
At Coating Management Solutions, we offer specialised support for all your industrial coating-related requirements. Please contact us today to build an effective coating system as per your needs.