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And the Nobel Prize for Industrial Coatings Goes To…

red-coilIt’s the 2016 Nobel Prize season, and there’s a prize for:

  • Chemistry: Molecular Machines (sounds cool, batteries not included)
  • Physics: “…for theoretical discoveries of…” (What on earth is a theoretical discovery? Aren’t there any actual discoveries to award?)
  • Physiology: Understanding the mechanism for the degradation of cells.

There is never a Nobel Prize given for Technology. But, if there were, let’s consider some candidates in the area of factory-applied coatings for metal:

  • Automotive Coatings—dazzling finishes, robotic painting, with coatings that last a lifetime (10 years, in this case)
  • Powder Coatings—0 VOC technology, high-temperature bake, thick films (2-5 mils)
  • Aerospace Finishes—must function under demanding applications
  • Metal Furniture Coatings—no particular demand placed on the coating, other than wear resistance
  • Coil Coatings–an area near and dear to our hearts

And the Nobel Prize for Industrial Coatings goes to Continue reading →


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Accelerated Weathering: Part One

“Not this topic again,” you might say. By “this,” you probably inferred that you are about to read a few hundred words describing the difficulties of meaningfully correlating accelerated weathering to real-time performance. Rest easy; that old topic is kids’ stuff compared to understanding the meaningfulness of corrosion testing.

The performance of coil coatings over the lifetime of a product is of paramount importance. Of the markets served by prepainted metal, the building products market poses the greatest challenges. During a recent NCCA meeting, there were plenty of conversations about accelerated corrosion testing, and this got me thinking about the similarities—and distinct differences—when comparing accelerated corrosion testing and accelerated weathering. Of course, corrosion is a form of weathering, but the term “weathering” commonly refers to what happens to a product’s appearance properties (chalk, fade, gloss retention) when exposed to sunlight, heat and moisture.  On the other hand, corrosion refers to the degradation of the metal substrate.

Great progress has been made over the last 20 years to understand how to model an accelerated weathering test to better simulate the environment in which a product will be placed. We now have a better understanding of the need to duplicate the solar power distribution, the unrealistic effects of <295 nm UV wavelengths, and, most recently, the importance and necessity of coating moisture imbibition in the physio-chemical degradation of coatings. This level of understanding is mostly absent when it comes to accelerated corrosion testing.

What makes corrosion testing so difficult? Let’s start with the chemistry of corrosion versus accelerated weathering. Don’t worry; I do not intend to get into the chemistry and physics. We’ll leave that to the researchers, but it is important to know that these researchers are always striving to duplicate in an accelerated test cabinet the same chemistry that is taking place in the real world. When done effectively, new products can be introduced with an assurance that they will perform suitably in the field.

As demanding as it is to understand the degradation reactions of an organic coating during typical weathering, understanding corrosion reactions is way more convoluted! Continue reading →


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Fun Facts: Know Your Sun

The Autumnal Equinox is upon us. OK, we know that this means that there are equal amounts of daylight and nighttime. We know that winter is coming to the Northern Hemisphere and that summer is coming to the Southern Hemisphere. But there are other Fun Sun Facts worth mentioning.

At the risk of sounding like a geocentrist, it is easier to describe the movement of the Sun as if the Earth were stationary and the Sun revolved around it. On the Autumnal Equinox, the sun is directly above the equator for this day. If you were standing on the equator at the Equinox, at noon, you would see no shadows, since the sun is directly overhead. The same thing happens on the Vernal (Spring) Equinox. If you want to check this out yourself, catch a flight to Quito, Ecuador, which is right on the equator. The official name of Ecuador, by the way, is the República del Ecuador, which translates into “Republic of the Equator.”

The sun is now making its visit to the southern Hemisphere, and has been doing so since the Summer Solstice (June 22 this year), that day when the sun is as far north as it ever travels. Its “equator” that day is the 23.5°N latitude, also called the Tropic of Cancer. Six months later the sun is as far south as it goes, and—you guessed it—the “equator” on that day, the Winter Solstice (December 21), is 23.5°S latitude, the Tropic of Capricorn.

These Solstice days make for interesting times in those communities lying at or above the Arctic Circle 66°N latitude. On the Summer Solstice, they receive 24 hours of daylight; the Winter Solstice brings them 24 hours of darkness. Here is a good representation of the Sun and the Earth on the Summer Solstice.

Continue reading →


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Securing Coils for Shipping and Related Requirements

The U.S. Department of Transportation, Federal Motor Carrier Safety Administration (FMCSA) provides specific requirements regarding shipping of products, including metal coils. The complete FMCSA requirements can be found in the Code of Federal Regulations. The following provisions of the code relate to securing cargo and safe loading:

  • Shifting or Falling Cargo: FMCSA, 49CFR393.100
  • Safe Loading: FMCSA, 49CFR392.9
  • Rules for Securing Metal Coils: FMCSA, CFR393.120

It is typical for shipping companies to properly secure cargo. Carriers assume responsibility for complying with DOT regulations, and coil coaters do not accept liability for the carrier’s responsibility to properly secure loads. Some companies require their carriers to acknowledge their familiarity with the federal shipping requirements and to agree to abide by the DOT regulations.

Some companies also include signs in their facilities to make drivers aware of their responsibility to be aware of the applicable regulations. An example of such a sign in a coil coating facility follows:

Notice of U.S. Department of Transportation Shipping Regulations: Continue reading →