The new sectional water tank required a regulation 31 approved tank lining suitable for water for the public supply. The externals also required an anti corrosion coating that would both protect the steel structure and provide an aesthetically pleasing finish.
As the panels were delivered to site having already been blasted and a holding primer applied it was first necessary to thoroughly abrade the existing primer to ensure adhesion of the new tank lining. This was done using powered orbital sanders.
Following preparation the tank internals were thoroughly vacuumed to remove debris and contaminants in order to ensure excellent adhesion of the new tank lining.
To ensure full thickness of the tank lining on angles and edges where coatings pull thin a heavy stripe coat of Sikaguard 62 was first applied. This was followed by a full coat and subsequent stripe coat and full coat if contrasting colour as per good coating practice.
Once cured the tank lining was tested for pin holing using a DC holiday spark tester. Where found these were marked with chalk prior to touching in using the same epoxy material.
The tank externals once prepared received a heavy stripe coat of a surface tolerant epoxy mastic to all angles, edges, nuts and bolts. This was followed by the application of a full coat of the same material.
To ensure an aesthetically pleasing a UV stable polyurethane top coat was applied (again with a stripe coat).
A particular challenge with this project was the fact that the works had to take place during winter months. To ensure the correct climatic conditions for coating application the entire structure was enclosed with sheeting and heated with indirect oil fired heaters.