ACHRNEWS

Technology Takes On Corrosion Challenge

April 29, 2005
The island of Guam in the Western Pacific Ocean has significance to that generation which fought in World War II and to those subsequent generations via history books and high school exams.

Ceded by Spain to the United States in 1898, it was captured by the Japanese in 1941 and retaken three years later. The famous Battle of Guam started in July 1944 with an American troop landing and ended in August 1944 with an Allied victory.

Today Guam is supported by tourism and the presence of U.S. military bases. The increasing importance of air conditioning on such bases in the years following the war resulted in a situation that required some new solutions and new technologies.

Battling Rust

Salt-air corrosion was creating the need to replace air conditioning coils every 10 to 18 months. So the U.S. Navy tried coils coated with a product called Technicoat 10-1â„¢. Overall, 1,100 such coated coils were installed at the base housing of Agana Naval Air Station.

According to the coating manufacturer, those coils remained in service for more than 12 years, and only then because the condensing units themselves - not the coils - were crumbling away.

TechniCoat 10-1 is described as "a proprietary epoxy-modified phenolic dip coating. It is an anti-corrosion coating described and custom-engineered specifically for HVACR coils."

TechniCoat Inc. was formed in 1970 in Fort Worth, Texas, to provide metal-finishing services. In 1972, the company decided to tackle the Navy's need for a better coating for coils in salt-air atmospheres. The result was TechniCoat 10-1 and, according to the company literature, the firm soon "had to abandon all other services and products to keep up with the demand for 10-1."

In 1990 the company joined forces with Aero-Marine Engineering and relocated to Bryson, Texas, some 70 miles northwest of Fort Worth.

According to AME-Technicoat's Kevin Burton, "All coils are dip-coated in a total immersion vat process and then heat-cured. No ‘flow coating' is ever done.

The result is a high-density, thin-film coating which can be applied to louvered fins without bridging. It creates a surface so smooth and free of microporosity, that it provides exceptional sheeting action."

Such sheeting action "means less fouling, easier cleaning, and prevention of microbiological contaminants," he said.

Burton added, "The epoxy modification of the phenolic eliminates the brittleness normally associated with straight phenolic coats and provides the flexibility needed to withstand the expansion and contraction of normal coil operation. It also creates a tougher coating which can better resist shipping and installation damage."

The coating technology means that OEMs can send coils to AME/TechniCoat for coating "in the flat" and then bend them into the required shapes after coating, according to Burton.

He noted that the process "does not lend itself to field applications; coatings must be applied at our plant."

He said that independent testing by OEMs and a research lab has demonstrated that the "K-factor of TechniCoat 10-1 is so close to that of aluminum that it has practically no effect on the efficiency of a coil."

For more information, visit www.ame-technicoat.com.

Publication date: 05/02/2005