If imitation is the sincerest form of flattery, then residents of Bolingbrook, Illinois, can take satisfaction when they see the identical purple fluoropolymer finish coat from Tnemec that is standard on all of the Village’s water tanks being used by neighboring communities. “The Purple Haze fluoropolymer finish coat makes these water tanks really stand out,” acknowledged Erik Otten, a sales representative with Taylor Coating Sales. “And since the Village of Bolingbrook standardized Purple Haze for all of its potable water tanks, several surrounding towns have decided to coat their tanks with the same color and coating system.”
HydroFlon was specified on exterior steel for its long-term color and gloss retention and outstanding resistance to ultraviolet (UV) light degradation. “The project’s applicator realized such a bright color would require a coating system with the highest level of performance or the color would quickly fade,” Otten recalled. “The applicator worked with the owner and convinced them that HydroFlon was the best choice as the finish instead of applying a full clear coat.”
The repainting projects consisted of the complete removal and replacement of the existing coatings. Exterior steel and interior non-immersion steel were prepared in accordance SSPC-SP6/NACE No. 3 Commercial Blast Cleaning, while interior steel used for immersion service was prepared in accordance with SSPC-SP10/NACE No. 2 Near-White Blast Cleaning.
Exterior steel received a primer coat of 91-H2O Hydro-Zinc, a zinc-rich aromatic urethane; an intermediate coat of Series 73 Endura-Shield, an aliphatic acrylic polyurethane; and a finish coat of HydroFlon. The interior lining system consisted of Series 91-H2O Hydro-Zinc and two coats of Series 20 Pota-Pox, a polyamide epoxy, which is certified in accordance with ANSI/NSF Std. 61 for use in potable water.
Otten added that blasting was unnecessary on one tank that had been coated with a Tnemec polyurethane coating 15 years earlier. “That tank received one coat of Series 73 Endura-Shield in a 10 percent lighter pigment than the finish coat,” Otten explained. “They also used a version of HydroFlon that was low in volatile organic compounds (VOCs).”
The Village of Bolingbrook shares the cost of repainting water towers with the Illinois-American Water Company. The Village covers the cost of the advanced fluoropolymer finish and adding its name and logo on the tanks.