Advances in Damage Resistant Coating Technology

摘要

Fusion bonded epoxy (FBE) coatings have been used on pipelines as protection against corrosion for50 years. They have been used as a stand-alone product in single layer systems and as a primer indual layer FBE and three layer polyolefin systems. Pipeline coating systems require physical propertiesthat minimize damage during transit, installation and operation. Damage to the coating leads to higherpotential corrosion sites on the metallic surface and could ultimately lead to a decrease in service life.There are several ways that have been used conventionally to attempt to make a FBE coating moreresistant to mechanical damage. In one conventional approach, the thickness of the overall coating isincreased to provide added absorption of impact and abrasion. However, as the thickness of thecoating increases, the coating has a increased tendency to crack. Another conventional approach toenhance damage resistance is to add an abrasion resistant overcoat that has a high filler loading toincrease abrasion resistance and decrease impact damage. However, higher filler loadings candramatically decrease the flexibility of the FBE coating. Yet another conventional approach to enhancedamage resistance is to use a three layer polyolefin coating system. Unfortunately, when damage doesoccur in these systems, cathodic shielding may allow corrosion to develop unchecked. This paper willpresent a novel coating system that incorporates both damage resistance and flexibility in a system thatis not subject to cathodic shielding.