When it comes to extending the service life of metal structures and components, an industrial painter considers three important factors: the corrosivity of the environment; the most suitable metal coatings; the most effective surface preparation techniques.
Because proper surface preparation is a fundamental factor in maintaining the appearance, performance and durability of coating systems, this post looks at the most important things business professionals should know about cleaning rusted and corroded surfaces.
Prepping Metal for Paint
Unprepared metal surfaces deliver an unsatisfactory substrate for painting, even if they’re in good condition. That’s because the level of surface preparation affects the adhesion of coatings to substrates along with their long-term performance.
To achieve the best results, a professional industrial painter typically uses different metal preparation methods, including:
Surface cleaning is often considered an essential first step prior to mechanical preparation. That is because some surface prep methods may simply spread certain contaminants over the surface rather than removing them.
If contaminants like oil, grease, dirt, soluble salts, loose rust and even moisture droplets become trapped under the new paint film, they will affect the adhesion and cause blistering or premature detachment of metal coatings from substrates.
According to industrial painters, proprietary solutions (e.g. mild-detergent or bleach solutions) deliver one of the most effective methods for cleaning painted surfaces. Additionally, acidic solutions and alkaline cleaners can be used for cleaning metal surfaces affected by rust or corrosion.
It’s important to note, however, that these solutions can pose a potential hazard to the environment and human health when improperly used, handled, stored, or disposed of.
Water blasting is another important preliminary step in cleaning metal surfaces before coating application or other surface prepping methods, such as abrasive blasting. Delivering a safe, effective and environmentally friendly cleaning method, water blasting is suitable for cleaning various metal components, including storage tanks, vessels, boilers, silos as well as concrete structures.
When done properly, abrasive blasting thoroughly cleans surfaces by removing fouling, salts, old paint, rust and corrosion. Additionally, this surface prep method creates a surface profile that promotes adhesion of protective primer coatings to metal substrates.
Depending on the overall surface condition and the profile required for the application of metal coatings, an industrial painter can use a variety of blasting media, such as aluminum oxide, crushed glass grit, glass beads, silicon carbide, plastic abrasive, steel grit, steel shot, and pumice. After abrasive blasting is completed, the surface must be thoroughly cleaned in order to remove any traces of dust and debris before painting commences.
Once metal surfaces are completely clean and dry, the industrial painter applies corrosion-inhibiting primers that are compatible with both the substrate material and the finish coat. Coating metal structures and components with the right primer will provide an effective barrier against a wide range of environmental factors, including moisture, water, salt air, acid condensation, and acid rain.
Thanks to new advances in paint technology, paint and coating manufacturers now provide a wide variety of water-based metal coatings that have excellent corrosion resistance, particularly when applied over zinc primers. Besides being easy to use, these paints are low in VOCs, which makes them less harmful to the environment and human health.
If you’re looking for the best industrial painting services that can protect and enhance the integrity of your metal structures and components, Performance Painting Contractors is ready to help you make the most of your painting project. Please contact our team today to learn more about our services or to require a free painting estimate.