What does Fusion Bonded Epoxy (FBE) mean?
Fusion Bonded Epoxies are thermosetting epoxy powders designed principally as a corrosion protection coating for pipelines, pipe fittings, support steelworks and, more generally, steel parts that require a high level of corrosion protection.
Fusion Bonded Epoxy coatings are therefore classified as protective coatings. The name is derived from the method of application and the cross-linking of resin as distinct from traditional paint systems. Fusion Bonded Epoxy coatings are more often referred to as FBE coatings in the industry.
FBE was first made commercially available in the 1960’s and, as you would expect, there has been some significant development over the years. Today, FBE coatings can be designed as a single layer application or as part of a multi-layer coating system. The properties of the various forms of FBE can also be modified to be adaptive to use; coating on fittings, parts, girth-welds, pipe bodies and internal surfaces.
The most important components of fusion bonded epoxy coatings are:
- Curing Agent
- Extenders and Fillers
The resin and curing agent bind together and can be viewed as the bedrock on which the FBE coating system is built. The extenders and fillers provide the various unique properties of the FBE coating and the pigment is the finish colour.
Traditionally FBE’s are applied by either fluid-bed dip or electrostatic spray/floc spray methods to heated steel parts, normally with an object temperature of 180oc – 250oc. The FBE powder then melts and becomes a viscous liquid that flows onto the metal surface and, through the application of the heat, it cross-links, becoming hard normally at around 93oc (sometimes called the glass transition point or Tg point).
The cross-linking process once complete cannot be reversed, once cured the FBE will never be able to return to the powder state. Where there are areas of the parts such as raised flange faces that are not required to be coated then it’s vitally important that the coating applicator understand this at the outset and masking is applied to prevent the coating being applied.
FBE Coating at Northpoint
Northpoint offers FBE coatings in Aqua/Green, Red and Blue with either Drinking Water Inspectorate (DWI) Approvals or Water Regulations Advisory Scheme (WRAS) Approvals for customers who supply pipework and fittings to the Water Treatment and Supply industry. The coatings meet the relevant requirements of EN 598 for chemical resistance pH 3 – 13 meaning the coating will not be adversely affected by disinfection prior to first use.
Northpoint has over 40 years of experience in FBE application and can provide professional assistance with pre-qualification, Project Quality Plans (PQP’s) and Inspection Test Plans (ITP’s). The finished coating can be provided with a document package that includes an ISO 10204 Document of Compliance signed off by NACE III and II Coatings Inspectors. Northpoint has also held ISO 9001 Accreditation for over 20 years continuously, a testament to Northpoint’s continued commitment to Quality Management and consistency of FBE coating supply.
Blog Author – Philip Dawson, Technical Advisor