ADVANCED CORROSION PROTECTION TECHNOLOGIES
AETC works with the U.S. government and commercial entities on implementing radical innovations in corrosion protection. The cost of fighting corrosion in the U.S. alone constitutes up to $1 trillion per year. Much of that cost could be reduced through better management and application of innovative corrosion protection technologies. AETC is pleased to offer two categories of technologies in corrosion protection. One is based on sacrificial anodes in subterranean and submarine installations, and on impressed-current cathodic protection. The second depends on anti-corrosive paints. Our specialty paint portfolio is based on chrome-free zinc-rich primers, which could be applied to metal surfaces with a minimum surface preparation level of SP3. That differentiates AETC from the rest of the market of paints and coatings, in which an excessive SP10 level of surface preparation is needed. On top of epoxy primers, AETC offers an innovative line of polyurethane-based top coats recognized for their durability and resistance to exposure to the elements. Besides the stable polyurethane formula, we carry a number of innovative pigments, some of which are based on spherical graphite and other conductive materials. The application of those pigments to the top coat drastically improves EMI shielding properties. AETC paints and coatings have been, and are currently being, tested at critical, industrial, and federal installations, including those in the most extreme geographies in terms of corrosive environments.
At AETC, we develop solutions for protecting metallic assets from corrosion through two main areas of technology: product/process design and accelerated testing/simulation.
Metal corrosion is detrimental to a multitude of industries, and the maintenance of metal systems therefore incurs tremendous annual costs. In fact, industry segment analysts estimate the United States spends up to $1 trillion annually to protect metallic assets from corrosion. The cost typically boils down to spending at least 2-3% of what has already been paid for the asset’s initial installation, as coatings or paints used on the metal objects would need to be reapplied or the installations may need to be replaced altogether. The need for corrosion protection increases the overall capital cost of an operation as well as its complexity; luckily, AETC is coming out with innovative solutions which would reduce the cost associated with maintaining anti-corrosive environments for our customers’ metal assets and systems.
AETC has designed and manufactured a variety of anti-corrosion paints with customers’ needs in mind, using various materials and chemical processes to ensure comprehensive protection of metal surfaces.
Zinc-Rich Epoxy Primer Paint
Firstly, AETC developed a zinc-rich epoxy primer to be applied directly on the metal’s surface as an undercoat before the application of the finishing layer of paint. The pigment of the primer ranges from nano-size to single-micron particles of zinc, which we are able to spheroidize using proprietary machinery. By spheroidizing the particles, we achieve a high packing density of zinc, which in turn results in more complete coverage of the surface and therefore better corrosion protection. We use zinc in anti-corrosion systems because it preferentially dissolves upon attack by corrosive elements instead of compromising steel or aluminum substrate without dissolving the metal to which it is applied. Our zinc coatings do not use chromate or other environmentally harmful chemicals.
Furthermore, the epoxy we use is a two-component system known to adhere to surfaces without the need for sandblasting preparation, which would require the object in need of anti-corrosion protection to be taken out of operation for several days; this would be not only costly and complex, but potentially disruptive in the operation of critical infrastructures.
Not only does the epoxy treatment bypass the need for sandblasting preparation, it is also applicable when anti-corrosion paint requires special types of surface preparation before application, often referred to as near-white metal surface prep, or SP-10 surface finish. If a given coating does not require SP-10 prep, its system may run interruption-free, and it would only need mechanical cleaning of the surface with power tools, followed by solvent degreasing before paint application.
AETC has developed these coatings. Our surface prep requirement ranges from SP-3 to SP-6, as we hardly ever require SP-10 prep, but our coatings are much more stable than a number of commercially-available counterparts that require the costly SP-10 prep.
Ultimately, we have invented a primer paint that is reliable, cost-efficient, and eliminates the need for complex, costly, and time-consuming surface preparation measures.
Polyurethane Top Coat
We created a variety of paints and coatings that can be used as top coats, typically applied as the second layer, on top of the zinc epoxy primer. These coatings are composed of layers of polyurethanes and specialty pigment-filled polyurethanes, which are not only aesthetically pleasing, but are also equipped with functional properties such as UV and scratch resistance, and sometimes with increased conductivity for engineered EMI protection as well as serving to protect assets during lightning strike-shielding.
Graphite-Filled Paint Formula
We also carry a range of graphite-filled formulas with rich black and grey colors. These coatings can divert heat from operating machinery, driving it into a bussbar which works as a conduit for removing heat from operating motors.
Galvanic Protection by the Method of Impressed Current
At AETC, we boast our expertise in battery technology. However, we found a way to apply battery technology concepts to create a paint that provides galvanic protection by the method of impressed current– a method similar to that used in our batteries, but instead the electrodes are several hundred yards apart rather than right next to each other.
Firstly, this technology requires an external power supply– this could be located in a shed or some such building on a company’s property, and would be running unmanned and with the lights off year-round to save costs. From this power supply, you would run two cables that serve as the electrodes. The negative terminal would run to the building or other metal asset being protected, attached to the underground metal infrastructure of the building. The other electrode, the positive terminal, is typically placed several hundred yards away, planted into a borehole. This electrode is made of light-weight titanium and coated with manganese dioxide, or other battery-grade active materials.
Sources of Ground Current
Our world is full of electrons. There are electrons inside the ground everywhere. They can come from local factories, for example, which have all of the electrical equipment grounded: the electrons travel into the ground with the electrical current from use of the equipment, but contrary to popular belief they don’t simply disappear– rather, they remain in the ground. Another source of electrons is lightning. When lightning strikes the ground, there is a brief influx of electrical current which leaves electrons in the ground. Yet another example is sand. In areas where sand particles are constantly moving– whether because of oil underground, hydrocarbons under the surface, or seismic planes subject to small earthquakes– the motion causes attrition between sand particles which in turn causes static electricity, and, by extension, spare electrons. So what happens to all of these billions of electrons? As they have negative charge, they look for any metal– pipelines, buildings, railways, or rebar– and if the metal is unprotected, it is attacked by electrons looking to neutralize their charge and it turns into metal salts.
For instance, a cruise ship docks at a pier in the Caribbean. While the passengers are off on land, the staff are running laundry, using lights, and in general are operating electrical machinery. Soon after the ship leaves, the pier collapses. This is because the steel rebars used to reinforce the pier were not protected, and were attacked by the electrons dumped by the ship’s electrical systems.
When we install galvanic protection systems, the building itself becomes a negatively changed electrical terminal. The coated titanium tube acts as an inexpensive sacrificial anode, and like in batteries it slowly dissolves manganese dioxide and produces tiny amount of oxygen byproduct. We designed our system in such a way that it should take up to 50 years to completely dissolve the manganese dioxide coating on the tube, and because our substrate is made of titanium we can pull the electrode out after all of the manganese has been dissolved and re-coat it for further use. Obviously, we have not been able to try this 50-year cycle yet, but our calculations demonstrate that this would be possible.
All of these findings help make corrosion protection of our clients’ assets cost significantly less than just reapplying paint. We can design a protection system for every need and calculate the right thickness and type of paint, and we can even offer our installation services and provide training on how to use the system.
After design and production, it is important that we test the quality, durability, and functions of the paints we develop. Not only do our assessments ensure the quality of our products; we also use these testing methods to design paints specific to particular clients’ needs, dependent mainly upon the weather and climate of our clients’ locations among other factors.
By going through dozens of rounds of different types of tests as part of a broader experimental program, we are able to find the set of chemicals which are optimal for resisting the effects of exposure. We offer continuous product improvement. If you are in Florida, surrounded by humidity and high temperatures, or in Alaska, exposed to snow and salt fog, and need advanced surface protection for your assets and infrastructure, or anywhere in between, reach out and we will see what we can do for you.
Though this test is apparently straightforward, it is a crucial quality check and can be one of the toughest to pass. The ASTM-referenced Scotch tape test requires simply adhering tape to the painted surface we want to test, and then peeling to tape and observing whether the paint peeled off with it. This test assures us of the product’s durability and is essential in the design of paints meant to resist extreme elements and environments without the need for touch-ups or reapplication.
We have clients located around the world, and therefore have to ensure that our products can resist a range of extreme weather conditions. Hence, we have to test our paints to ensure they can withstand the conditions of the environments they will be used in. To do this, we first turn to our group of talented statisticians and mathematicians, who work hard on responding to our customers’ specific requirements and research the climate conditions in our customers’ locations. The statisticians gather raw data on weather patterns, sometimes focusing in on areas as precise as specific villages, and then they write mathematical models to account for this data.
Next, we plug this data into a sophisticated accelerated weathering tester called the QUV Weatherometer. This machine subjects metal panels coated with our paints to abusive environmental conditions, such as intense humidity, UV light, rain, and extreme temperatures. The epoxy component of our primers makes the coats essentially pore-free, and in addition to this we may add other elements to paints that act as natural barriers should they need it in the environment in question, further protecting the metal substrates. Many commercially-available coatings, which look beautiful when freshly painted, fail our 504-hour long weathering tests– some coatings develop blisters underneath the paint, or bubbles that may burst, creating craters in the coat and therefore exposing the metal to corrosive elements. In other cases, the porosity in the paint’s composition allows for seepage of moisture, and even though the coating seems unscathed, the metal substrate beneath the paint is rusting, and this is not even noticeable until the metal has already rusted and needs repair.
If you are operating in extreme or particular weather conditions and need anti-corrosion paints tailored to your requirements, contact AETC.
For marine installations and assets located near seashores, corrosion problems intensify exponentially. This has to do with increased salt content in the windy air and salty fog coming from the water. In order to understand how a particular coating would fare under the conditions of a specific marine environment, we operate an industry-standard salt fog accelerated weather tester. We are able to load the testing chamber with dozens of coated panels, and then we subject them to exposure by mist aerosol with >5% salt content, resulting in the appearance of pitting corrosion stains and cracks in poorly-protected metal objects