Fusion Bonded Epoxy (FBE)
Definition - What does Fusion Bonded Epoxy (FBE) mean?
Fusion bonded epoxy (FBE) coating is a powder coating broadly used to provide protection to pipelines, steel pipes and a wide range of piping bonds. FBE coatings are thermoset polymers by nature.
In the coating nomenclature, fusion bonded epoxy coatings are classified as protective coatings. Its name was derived from its application methods and the cross-linking of resin that is distinct from traditional paint.
FBE is also known as fusion bond epoxy coating.
Corrosionpedia explains Fusion Bonded Epoxy (FBE)
FBE was first introduced in the 1960s and it has gone through significant developments since then. At present, different forms of FBE coatings are manufactured to suit various needs. It can be multi-layered or stand alone, and may possess different properties to suit application of coating on parts like fittings, girth welds, pipe bodies and internal surfaces.
The important components of the powder coating include:
- Curing agent or hardener
- Extenders and fillers
- Color pigments
The hardener and resin combine as the bond or binder. The curing agent acts to form the reaction, while pigments, fillers and extenders give off the desired properties. Normally, the hardener components and resin in FBE dry powder stay inactive under normal storage situations. At usual temperatures for coating, ranging from 180°-250°C, the powder contents melt and turn to a liquid state. The liquid form of FBE will flow onto the metallic surface and soon transform to its solid form through element cross-linking facilitated by heat. The process involved in this is termed "fusion bonding." The cross-linking that occurs in the chemicals cannot be reversed in this case. Once the curing happens, the coating is not capable of going back to its original state. Subjecting the coating to further heating will not make the coating melt, so it is known as a thermoset type of coating. During the fusion bond epoxy process, the following occurs:
- The surface of the pipe is cleaned and exposed to heat.
- Epoxy powder is applied onto the surface of the pipe electrostatically.
- The FBE powder undergoes melting onto the pipe surface and dries quickly in controlled and uniformed thickness.