Fusion-bonded epoxy powder coatings were first successfully developed in the United States in 1961 and subsequently applied to pipeline corrosion protection projects. Since then, they have been further developed and widely adopted in many countries.
Chinese name: Single-layer fusion-bonded epoxy powder
Developing country: United States
Development time: 1961
Use: For pipeline anti-corrosion projects
Performance
Due to its strong adhesion to the steel pipe surface, excellent resistance to chemical media corrosion, and superior temperature tolerance, as well as outstanding performance in corrosion resistance, resistance to cathodic disbondment, aging resistance, and resistance to soil stress, fusion-bonded epoxy powder coatings have a wide service temperature range (typically -30°C to 100°C). As a result, they have become one of the primary coating systems both domestically and internationally for internal and external pipeline corrosion protection. However, because the coating is relatively thin (0.3–0.5 mm), it has poor resistance to impacts from sharp objects and is easily damaged upon impact. Therefore, it is not suitable for rocky terrain but is well-suited for most soil environments and directional drilling applications through cohesive soils.
Structure
Fusion-bonded epoxy powder coating, abbreviated as FBE, features a single-coat film structure for its outer coating.
Apply coating
During application, the surface of the steel pipe exterior shall be blast-cleaned (or shot-peened) to reach the Sa2.5 grade specified in GB/T 8923. The anchor profile depth on the steel pipe surface should be within the range of 40 to 100 μm. Furthermore, the temperature of the steel pipe exterior immediately before epoxy powder coating must be monitored and kept within the range recommended by the powder manufacturer, but it must not exceed 275℃.
Repair
When defects are discovered on FBE pipelines, first remove all rust spots, flakes, cracks, dirt, other impurities, and loose coatings from the defective area. Then, grind the defective area to create a rough surface, thoroughly clean away any dust using a dry cloth or brush, and apply a localized repair using a two-component liquid epoxy resin coating.
