case study:
Concrete SEWAGE TANK LINING

To ensure proper adhesion, a certified ArmorThane applicator applied a cementitious fairing coat called FlexCrete as a mechanical profile for the tank lining. Surface roughness is crucial for most tank linings to achieve adequate adhesion.

The fairing coat was allowed to naturally hydrate, and its completion was confirmed through moisture testing of the substrate using a Tramex Concrete Moisture encounter gauge, which is part of our standard quality assurance process.

We also tested and recorded climatic conditions, including relative humidity and dew point, to ensure the correct conditions for applying the tank linings. Disregarding these conditions would result in the tank lining being applied to a moist film, preventing proper adhesion and leading to premature failure.

All surfaces were primed with ArmorSeal, a damp-tolerant primer, applied using a brush and roller. This versatile primer can tolerate substrate moisture content of up to 6%, reducing the required hydration period before applying the tank lining.

Following the priming process, two coats of ArmorThane ArmorLiner were applied in contrasting colors, following the best practices for tank linings. We used wet film thickness combs to ensure the proper thickness of these coats, as part of our standard quality assurance.

After the third coat of the tank lining cured, we checked for porosity using a DC Holiday spark tester. This test involves running a high voltage/low current energized copper brush over the surface, which identifies any breaks or holidays in the tank lining through sparks and alarms. This process is commonly known as spark testing.

Even a single pinhole in the tank lining can lead to failure, as it allows aggressive agents like biogenic sulphuric acid to reach the concrete and initiate corrosion. Therefore, it is crucial to identify and address any such points of failure.