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Pittsburg Tank and Ecodur 201S: Water Tower Coating

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Concrete silo-style water towers are less common than the bulbous ones that commonly stand beside small towns in North America. When and if they develop leaks, a typical solution to the problem is to line them with steel and apply a conventional epoxy coating. In this case, a water tower in Pickle Lake, Ontario, Canada, had a long history of leakages. A steel lining had been inserted but, unfortunately, the liner’s support on the concrete base had been wood which eventually rotted, stressing the welds to the point of failure when corrosion inevitably took its toll, causing the tank to leak.
 
Problem
A permanent leak prevention solution plan had involved welding steel patches and blowing in liquid concrete and sand to provide a supportive base. But what was finally needed was a highly robust corrosion protection coating solution that could withstand natural movement associated with temperature fluctuations. Conventional epoxy coatings typically micro-crack with expansion and contraction of steel, allowing moisture and corrosive elements to attack the steel it was supposed to protect.
 
All work on the tower was very difficult because of height involved at the top and the lack of access at the base of the tank itself. Applicators had to be winched down. Heat also had to be applied inside the tank to warm it and dispel moisture. Given that Ecodur 201S has excellent fire retardant qualities, this was not an issue as would have been the case with most conventional solvent-based epoxies as excess heat only creates water vapor with this natural product.
 
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Solution
The steel tank was duly prepped with Ecodur 201S chosen to provide a robust, flexible, long term solution with a coating that was also rated for safe contact with potable water, the NSF 61 rating. Ecodur 201S also had the additional advantages of being VOC-free with no solvents used either in the content, application itself, or post application clean-up and spray equipment maintenance.
Ecodur also noted for being a one pass treatment and its ability to re-bond to itself indefinitely for those all-important touch-ups and possible longer term maintenance treatments.
 
The lowest ambient temperate at one point during the application was a very chilly 20F and Ecodur’s outstanding winter performance characteristics meant that this did not prevent or compromise the procedure. There are few conventional epoxy coatings that can be applied at such low temperatures.

 
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Application Results
At various stages, the coating was stopped to replenish supplies. Again, because of Ecodur’s infinite ability to re-bond, downtimes did not compromise the integrity of the entire coating. The client commented very favorably on this as well as the lack of odor, adjustable cure rates and relative ease of application. The tank was rapidly returned to service within hours of completion and no further leaks have been reported.
 
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For more information on how our coating products can help you, please contact Pittsburg Tank & Tower Group (below) or us at: info@castagra.com

Contractor: Pittsburg Tank & Tower Group
Patrick Heltsley pheltsley@watertank.com
Don Johnston djohnston@watertank.com