Coatings for Utility Structures

Madison Chemical pioneered the concept of using of polyurethane coatings for tubular structures over 20 years ago and has led the industry ever since. Throughout that period, our CorroCote® II Classic brand name has become so ubiquitous that applicators don’t just talk about coating poles, they talk about “CorroCoting” them.

Raising the bar on quality has been our first priority over the years. In 1993, Madison commenced a training and certification program for coating application technicians. In 1998, we developed ISO 9001-compliant Quality Assurance Documentation; over the intervening decade since then, this documentation has been adopted to some extent by virtually every major manufacturer of transmission poles in America. In 2002, Madison authored and published a Power Pole Coatings Manual™, the first and only document of its type ever prepared for this industry. Today, that manual resides in the library of almost every company involved in the fabrication, galvanizing or coating of embedded tubular structures in North America.

But that was only the beginning. Since 2000, Madison has invested over $100,000 in research specifically for the benefit of this industry. Summarizing some of our findings, a senior member of Madison’s Research and Development team wrote a comprehensive technical paper on the state of the art as it was in 2003 and presented the paper as part of the Steel Structures Painting Council annual conference that year. To view that technical paper, please click here.

This body of research has led to a broader knowledge of the complexities of surface preparation, the role of equipment maintenance, the promulgation of standardized applicator techniques and a greater ability to predict service life. Today, it is literally possible to decide on the desired service life and then design a system that will attain that lifespan. Choose from basic protection to multi-decade design life; with Madison coatings, it all a matter of choice.

However, one intransigent technical problem remained. Blasting of the zinc was the only way to get a long term result but the blasting process, by its very nature, was removing some of the newly applied zinc and potentially fracturing what remained. Also, blasting is impractical for field work on either new or existing structures.

The illusive search for a less invasive form of surface preparation met with two unexpected successes in 2007. Firstly, it was discovered that a relatively simple formula modification increased adhesion significantly, on the order or 50%, especially where conditions were less than ideal and the bond might otherwise be marginal. Secondly, and even more surprisingly, our research team developed an easy to use non hazardous and environmentally “green” surface conditioner/adhesion promoter named GalvaGrip, that worked synergistically with coating to create levels of adhesion comparable to near-white blasting on galvanized steel and to a commercial-grade sandblasting on weathering steel without doing any destructive and expensive blasting, thus enabling the user to eliminate blasting altogether!

To achieve the above mentioned results without blasting, simply apply GalvaGrip with a low pressure sprayer to the structure and allow GalvaGrip to penetrate the surface for about 20 minutes. Then rinse with a high pressure stream of tap water using a power washer and thoroughly dry prior to application of the coating. It is that simple.

Besides being cost effective, the new process is much easier to control because there are so few variables compared to blasting. Capital costs for building a blast facility are eliminated. The performance results are comparable to a white metal blast with steel grit (which has always been regarded as the “gold standard” of surface preparation).

The list of products in the table below illustrates the breadth of Madison’s offering. CorroCote II Classic® continues to this day to be a staple of the embedded pole industry. This one-coat self-priming fast-throughput product today quietly protects hundreds of thousands of poles all across North America. It has been approved for embedded structures by UL for over 30 years! Its Mix-and-Apply cousin, CorroCote ‘S”®, handles like paint, making it ideal for field touch-up and repair.

For pedestal mounted structures and the upper portion of embedded structures, there is a wealth of choice. In addition to the one coat, fast set, plural component choices, there are a number of more paint-like systems.

The two topcoats we recommend are AcrylaThane® 5200 and Tufsheen PreCatalyzed®. AcrylaThane 5200 is an aircraft grade Mix-and-Apply polymer product reinforced with NanoShield™, an additive consisting of extremely fine nano-spheres of real ceramic. If you are committed to quality longevity, look no further. Tufsheen PreCatalyzed is, as the name suggests, a ready to use alternative; just open the can, give it a stir, and put it on. It sets more slowly than AcrylaThane 5200, but the easy to use format makes it the ideal choice for field applications.