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Towering achievement

How Drytec found the solution to make the Freedom Tower shine.


Wrapped around the southern curve of Manhattan Island, the New York Harbor is illuminated by two iconic beacons that project the light of freedom: the torch held aloft by the Statue of Liberty, and the gleaming spire atop the Freedom Tower, One World Trade Center. The history of each structure is known worldwide. But the techniques used to make their lights visible from afar tell another, lesser-known story that illustrates how much one element of technology has advanced during the past 30 years.

When the Statue of Liberty was renovated in preparation for its 1986 centennial, its original torch (now on display in the pedestal) was replaced by a flame sculpted of copper and overlaid in 24-karat gold. Although stationary and not an actual flame, it creates a flickering illusion by reflecting the sun’s rays during the day and strategically positioned floodlights at night.

30 years later, the One World Trade Center spire gets its glow (and the conductivity required for its use as an antenna) from a zinc coating sprayed on with a specialized application gun. You could say the team that put the finishing touches on it reached this pinnacle by implementing a solution that exceeded the gold standard.

But there’s something else that sets this spray tool apart from today’s steady barrage of headline-grabbing technology: it isn’t new. In fact, it was developed by Oerlikon Metco decades ago—and nothing created since then turned out to be capable of meeting the specifications involved in managing the geometric complexities that this project presented. In fact, the challenges defeated many more recently developed technologies.

The spire stands at 408 feet in height and 20 feet in diameter at its widest point, but its dimensions only hint at the intricacy of the structure and the coating challenge it presented. Constructed in 17 sections, each of which consists of a network of 12 interlaced pipes, its configuration includes many corners, angles, and variations in thickness. Achieving complete and uniform coverage of such a complex surface was a daunting task.


Click on the Infographic to see more facts about the One World Trade Center


Quebec-based Drytec Trans-Canada, which specializes in surface treatment and corrosion protection services, had to manage the process under strict time constraints. These were established to ensure that the zinc was applied evenly and that no part of the spire, no matter how minute, was left exposed to the elements and therefore to structural damage.

The Drytec team spent a year testing tools proposed to deliver this precision coating. The company had to get the job right the first time when working with the actual spire, so it invested many hours in choreographing and rehearsing the steps necessary to complete the work seamlessly. But while it succeeded in perfecting the human elements—the well-defined individual roles that had to be coordinated to achieve flawless teamwork—without the right tool, the secret to execution remained elusive.

“Despite our experience with other projects, we had to adapt and think as a team in order to realize this project under optimal conditions,” says Gaétán Hébert, maintenance and supply coordinator. “We knew that this project was impossible to realize with our own equipment. Therefore, we contacted Oerlikon Metco as a possible partner.”

The company’s Metco 16E wire combustion spray gun proved to be the link between envisioning and executing the coating procedure. It’s not the newest technology that Drytec tested for the project. But in this case, “new” never equated with “improved,” and that reality parallels neatly with Oerlikon’s philosophy of innovation.

“Our goal is to be the company that offers the most appropriate solution and technology for our customers,” says Andreas Bachmann, Head Communications at Oerlikon Metco. “For some challenges—including high-profile projects like the Freedom Tower—the optimal solution need not always be the latest advance, but rather the product of many years of proven reliability and experience. That’s what made the difference at the World Trade Center, and that’s what sets us apart as a company. To offer our customers new and innovative and likewise tried and true surface solutions.”

The solution won praise for its precision and efficiency as well as its prevention of future maintenance headaches: the completeness and durability of the coverage alleviated site inspectors’ fears that the coating would require touch-ups within a few years.

Photos of the tower are on display at Drytec’s offices and attract most visitors’ attention. They often express surprise on learning that the company built the spire. “We knew that this project would attract attention from around the world and that our company would be known for its innovative technologies,” Hébert says. “We are now more convinced than ever that we are able to realize projects regardless of their complexity.”

Rising above one of the world’s most recognizable skylines, the Freedom Tower is a reminder of how far we can reach when we employ ingenuity. We look up to it for inspiration as we continue to seek innovations—those still in development as well as those brought to market long ago—that deliver value to our partners and help them to rethink and redefine what is possible.

Time Picture

Have a look at the View from the Top of the One World Trade Center (©TIME)

By Randy B. Hecht

Pictures ©Fotolia, John Anderson




  2. Hari Dhungaa

    Very well described. Interesting reading.

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