Modern high performance paint systems are so durable that when exposed to natural weathering they may show only slight signs of deterioration. This means that new coatings being marketed have limited track records. Which creates an increased reliance on accelerated laboratory testing to evaluate performance.
Optimisation of maintenance and inspection programmes through risk analysis can be used for coating maintenance. The risk picture can be described by 1) Scenario, 2) Frequencies, and 3) Consequences, for protective coatings. A systematic approach for optimisation of the maintenance programme has been developed.
Three layer polypropylene (3LPP) pipeline coatings failed prematurely in the oilfields of Abu Dhabi in the United Arab Emirates (UAE). A failure investigation and analysis into this phenomenon was instigated. The coating disbondment has been found to be due to high residual stress concentration and adhesion loss.
Damage to coatings leads to higher potential corrosion sites on the metallic surface and could ultimately lead to a decrease in service life. This paper will present a novel coating system that incorporates both damage resistance and flexibility in a system that is not subject to cathodic shielding.
Outdoor tests and accelerated weathering experiments have been carried out to confirm the weathering performance of coating systems with ambient cure fluoro-polymer topcoats. The results showed that the protective performance of such coating systems was superior to other topcoats such as polyurethane coating.