A Look At Industrial Coatings and Their Applications

Various types of industrial coatings have different chemical and physical properties-- deterioration resistance, performance when exposed to UV, and so on-- however, no coating offers all the protection a structure needs. That's why properties are coated with several coating types to form an overall protective coating system, or a system offering all the chemical, physical and galvanic protection needed to safeguard the substrate from its environment.

Understanding the most common coating types-- and how they work to form a total protective coating system-- allows designers and owners to pick the system best-suited for their project.

Industrial Coating

Here, we'll explain the benefits and tradeoffs of 4 of the most typical generic coating types: Epoxies, polyurethanes, polysiloxanes, and zinc-rich primers, providing examples of how each might be used in an overall coating system.

Epoxies

Epoxy coatings generally consist of an epoxy base and a curing agent. A wide variety of coating homes can be attained by controlling either of these parts: Epoxy polyamide coatings offer great moisture resistance, epoxy mastic coatings offer exceptional film thickness, and phenolic epoxy coatings offer good chemical resistance. And due to this versatility, you'll find epoxies used as a primer, intermediate coat, or even a top coat, depending on the needs of the application.

And due to this versatility, you'll find epoxies used as a primer, intermediate coat, and even a topcoat depending upon the application's requirements.

The most significant limitation of the epoxy household of coatings is their poor performance in sunlight-- which is why epoxies are usually utilized in the interior or submerged industrial applications. You might find epoxies protecting steel inside a nuclear reactor or immersed in a wastewater treatment facility.

Abrasion-resistant

Chemical resistant

Excellent efficiency when immersed

Can quickly construct film density for enhanced abrasion resistance

It can be developed to exhibit a wide range of favorable coating properties.

Disadvantages

Chalks, when exposed to UV light.

Low flexibility

Polyurethanes

Polyurethane coatings are commonly utilized-- often as an overcoat-- in applications where toughness and abrasion resistance are essential factors to consider. Polyurethanes normally fall under two classifications: Aliphatic and fragrant. Aliphatic polyurethanes offer outstanding color retention and carry out well in sunlight, making them appropriate to exterior environments. Fragrant polyurethanes, on the other hand, better lend themselves to submerged environments-- they'll chalk and weather condition when exposed to sunshine.

Usually, polyurethanes are picked as the overcoat of a total protective coating system. For example, polyurethane might be applied as a topcoat above a zinc-rich guide and epoxy intermediate coat on a highway bridge. And even as an overcoat on the concrete walls and floors of a nuclear power plant. Other possible applications include the topside of ships, outside drainage treatment centers, or on locks and dams. Polyurethanes are flexible sufficient to be developed to handle a wide range of service environments.

Benefits

Abrasion-resistant

High gloss and color retention

Aliphatic polyurethanes perform well against weathering and UV light.

Aromatics carry out well when submerged.

Low VOC formulations available

Drawbacks

Includes isocyanate (- NCO), a hazardous carcinogen

Skilled workers and protective equipment are essential for the application.

Greater priced than epoxies

Polysiloxanes

Polysiloxane coating systems are a reasonably brand-new addition to the marketplace, only dating back to the 1990s. Polysiloxanes provide outstanding abrasion and weather condition resistance and appearance retention advantages; however, they fail to supply the flexibility and corrosion resistance industrial environments need.

Combining the advantages of epoxies with polysiloxanes-- into epoxy polysiloxane coatings-- offers industry-leading abrasion, weather condition, UV, chemical, and deterioration resistance. Although epoxy polysiloxane hybrid coatings cost more than epoxies and polyurethanes, they can be applied quickly and last longer-- offering much better long-term value for many applications.

Because of their performance and longevity, epoxy polysiloxanes have been utilized by the United States Navy to minimize its vessels' lifecycle cost. However, this coating type can be utilized in many industrial applications, including highway bridges, marine structures, wastewater treatment plants, tanks, or anywhere that requires a lasting, high-performing coating system.

Advantages

Excellent resistance to abrasions and weather condition

Allows for two-coat applications (zinc primer and polysiloxane) instead of the common three-coat application (zinc, epoxy, and polyurethane), in return cutting labor costs

Great color and gloss retention

Excellent performance when exposed to UV.

Higher optimum service (~ 200-1400 degrees) temperature level than other systems

Downsides

Touch-ups may be visible due to imperfect color-matching

Higher material costs than epoxies

More recent item-- just around considering that about the 1990s

Organic and inorganic zinc-rich

As a generic coating type, zinc-rich coatings refer to natural (i.e., including epoxy or polyurethane binders) or inorganic (i.e., including silicate binders) coatings with high loadings of zinc dust. The zinc provides galvanic protection of the steel surface area, meaning that it will wear away instead of the steel beneath it. As the zinc-rich coating corrodes, it forms a barrier between the steel and its environment.

Inorganic zinc-rich coatings tend to supply better galvanic defense and abrasion resistance than do organic zinc-rich coatings. However, they need a much greater level of surface preparation. Both variations perform well as a primer in a multicoat system, as they adhere well to the steel surface area.

Zinc-rich primers will typically be used as part of a two-coat (zinc-rich primer, polysiloxane overcoat) or three-coat (zinc-rich primer, epoxy intermediate coat, polyurethane topcoat) system. You'll find zinc utilized in a wide range of highly destructive environments, consisting of bridges, coal plants, and the topside of ships.

Benefits

Supplies both galvanic and barrier defense to steel

Abrasion-resistant

High level of durability

Drawbacks

Must be top-coated in lots of applications

Inorganic zinc-rich coatings require an extremely tidy surface before application.

Both inorganic and organic variations have a low resistance to acid and alkali.

Selecting a coating system for your application: Weighing cost and efficiency.

Industrial coating systems offer steel structures with long-term security against their environment. To do this, the coating system should be fully equipped to deal with the environmental conditions of its environment, whether that's heat, sunlight, contact with chemicals or continuous abrasions.

The dominating service environment-- in addition to elements such as expense, ease of access of the asset, anticipated labor costs, the typical life span of the coating system-- will determine which coating system is best suited for your application.

For designers or owners searching for a list of coating systems suited for their application and budget plan, calling a coating specialist like ArmoThane is a great place to start. Coating choice occurs on a case-by-case basis. ArmorThane can evaluate your application's particular needs using several systems that might work based upon our decades of experience in the industry. Contact ArmorThane today to learn which coating system will work best for your needs.