Many asset owners may not understand the different options available within thin film urethane technology. If they use a common specification database, their specifiers might be accustomed to cutting and pasting requirements from similar past projects into new specification documents. Will these specifiers look at the chemistry being used and ask whether options are available? Maybe not. In some cases, projects may be specified by applicators leaning toward the lowest-cost option rather than the most durable atmospheric system.
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Urethane chemistry is very broad in scope with many nuances, some that can benefit industrial asset owners more than others; however, all urethane systems have a place in the market. The purpose of this article is to provide information, particularly to owners of carbon steel assets — both fixed in place and rolling stock — so they can ask the right questions when specifying upcoming projects.
Types of Urethane
“Urethane” is a very general term. It can be a catalyzed alkyd enamel, a true polyester urethane or some formulation in between. Acrylic, fillers, pigments, polyester and solvents are all considerations when identifying the best urethane for a project.
Most urethanes specified today are acrylic-modified urethanes. Acrylic urethanes are similar to what is used to protect the surface of your car or truck. Imagine chloride-laden cooling water drifting over your vehicle. The heavy minerals would likely scratch and damage its sheen. While acrylic urethanes have their place, a true polyester will perform better on surfaces exposed to the harsh chemicals most commonly found in plants, refineries and well sites. Polyester urethanes are much harder and more chemical-resistant and will hold up longer in aggressive environments.
Cost and Efficiency
Labor is always the most expensive component of an industrial project, so it’s important to use products that will last. Critical applications where owners need longevity and durability require higher-quality urethane products. Catalyzed enamels and acrylic urethanes typically won’t last in environments where there is aggressive chemical exposure, high abrasion or severe UV exposure. Specifying a more durable urethane product can extend the repaint schedule two to three years or longer.
Color control is also critical. Without reliable batch consistency, color can fluctuate wildly and cause issues. Paint manufacturers save money by allowing a wider color variance between batches of paint. Many manufacturers allow a 2 to 3 Delta E variance between batches of urethane. The human eye can typically distinguish anything over 1 Delta E. By working with a company that has tight control over batch color consistency, customers can save money. As an example, a project may use components built in different locations throughout North America. When these components are assembled color variance is common. Correcting that variance can cost the owner significant, unbudgeted money.
Another potential color issue is the quality of pigment in the urethane. Many of the industrial acrylic urethanes used in the market today utilize industrial pigments, which are cheaper, but certain colors such as red and yellow will start to fade within six months. Urethanes that use automotive pigments will last longer and not fade as quickly, thereby extending the repaint schedule and saving the asset owner money.
Specifying the proper urethane technology for a project is critical to the overall appearance and longevity of an asset. An owner who works as part of a team with manufacturing and application can be assured a successful project that will last for many years.