One of the common reasons for the need for periodic repair and maintenance in a facility is when epoxy coatings failure occurs. Facility managers are pressed to allocate the needed budget and tolerate the amount of work disruption required to repair the coatings failure, because of the negative effects in the facility if the polyurea failure is not rectified as soon as possible.
Epoxy coatings failure occurs for many reasons, foremost among them is the coating system’s constant interaction with various elements in the surroundings. Understanding the major causes of coating failure leads to better choices of coatings material, more careful surface preparation and application, ultimately reducing the occurrence of disruptive coatings failures in the facility.
Coatings Failure Due to the Elements
The natural and constantly interacting forces of sun, air, and water are the most frequent causes of failure in facilities. Sunlight can breakdown the chemical composition of the coatings, and daily exposure to the sun’s rays combined with chemical deterioration can lead to coatings failures. The careful selection of ultraviolet-resistant epoxy coatings products can withstand the sun’s onslaught far longer than ordinary coatings material.
The presence of water, even in small quantities, is also another cause of premature coatings failure. Concrete surfaces are particularly vulnerable because they retain water much longer, and damp areas can never be totally dried out. Water interaction with high humidity also produces moisture that causes coatings to fail after some time.
Some facilities are always submerged in water, wherein standard coatings will simply fail. The solution? A new breed of solvent-free coatings whose epoxy formulation actually repels water, ideal for underwater structures.
Coatings Failure from Surface Particles
Slightly lesser in frequency than elemental causes, particulate matters are also one of the major causes of coatings failure in facilities. If surfaces are not properly prepared or cleaned prior to coating application, the presence of dust, dirt, grease and other foreign particles hinder the epoxy coatings from totally bonding with the surface to be coated. The lesser adhesion of the applied coatings increases the possibility of premature coatings failure.
In steel surfaces, the presence of nearly-invisible salt deposits often remain despite surface sandblasting, attacking the metal surface underneath the epoxy coatings, causing irreversible corrosion and eventual failure. Surface preparation through hydro blasting can remove these residual particles.
Other Causes of Coatings Failure
Solvents sometimes help in dissolving foreign particles in epoxy coatings, but the downside to using solvents in epoxy coatings is that they can often result in surface ridges in coated surfaces where there are thick coatings. If the coated surface dried too quickly, trapped solvents underneath will form these ridges and cause the topcoat to fail. The only solution is to use solvent-free epoxy coatings.
Other causes of failure are the inherent brittleness of phenolic coatings that crack when surfaces move, expand, or contract. When coatings crack, they open the surface to corrosion and moisture damages. To solve brittleness, the epoxy coatings product must have good elongation properties. Porous epoxy coatings, on the other hand, lead to blistering because water or chemicals are freely absorbed by the coatings. Knowledge of non-porous coatings and their application can help lessen the risk of failure.