
The state of your protective coatings is an indicator of possible future repairs for your bulk gas storage tanks.
When applied correctly, protective coatings can increase the longevity of steel assets by protecting them from corrosion damage. Most business owners or plant operators want to avoid those costly, totally preventative repairs. To avoid, corrosion damage, you must be able to identify when there is a protective coating failure.Here are 5 coating failures to watch for during your next equipment survey:
Loss of Adhesion
Loss of adhesion presents itself when the paint system does not adhere correctly to the base surface. You can tell if a coating does not adhere correctly through a pull-off test. If left untreated, the paint will flake off, revealing the unprotected base. The steel is now vulnerable to environmental concerns like corrosion. Loss of adhesion occurs when any of these factors are present:- Surface contamination
- Unsuitable primer or primer application
- Exceeding the overcoating time

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Chalking

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Blooming
Blooming is best described as a loss of gloss or dulling of the paint color. It is caused by paint not having enough time to cure before low temperatures hit. This coating failure can be easily avoided by the painting contractor by avoiding painting during rain or cold weather. If the coating has bloomed, a repaint must be issued.
Cracking
Cracking or “alligatoring” happens when the steel surface shrinks faster than the body of the paint film. This can happen when a topcoat is applied before the undercoat has dried. Cracking can also refer to “alligatoring” because the texture of the failure is similar to the skin of an alligator.
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Bridging
Bridging is the result of poor coating application. This coating failure happens when cracks or corners are not covered correctly. Gaps in application introduce a weak point for the coating, which can cause premature corrosion issues. Protective coatings should be brushed into corners and over welds.
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