Comparison Between Glass-Fused-to-Steel & Fusion Bonded Epoxy Coated Steel

Glass-Fused-to-Steel (GFS) and Fusion-Bonded Epoxy (FBE) Coated Steel are two popular corrosion-resistant coatings used in various industries to protect steel structures from corrosion and harsh environments. While both coatings offer excellent corrosion protection, they have distinct characteristics and applications. In this comparison, we will explore the differences between Glass-Fused-to-Steel and Fusion-Bonded Epoxy Coated Steel:

1. Coating Composition:

   Glass-Fused-to-Steel (GFS): GFS is a unique combination of two materials - glass and steel. The steel substrate is coated with a layer of enamel (glass) on both sides, and then the enamel is fused to the steel substrate through a high-temperature firing process. This fusion creates a highly durable and chemically resistant bond between the glass and steel.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE is a two-part epoxy coating applied to the steel substrate through a fusion bonding process. The epoxy resin and curing agent are mixed and then applied to the heated steel surface, where they chemically react and bond to form a protective coating.

2. Corrosion Resistance:

   Glass-Fused-to-Steel (GFS): GFS provides exceptional corrosion resistance due to the impermeable glass layer, which acts as a barrier against corrosive elements. The glass enamel resists chemical attack and protects the steel substrate from corrosion caused by moisture, chemicals, and other environmental factors.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE also offers excellent corrosion protection. The epoxy coating forms a strong and durable barrier that prevents corrosive substances from reaching the steel substrate. FBE is particularly effective in protecting against soil, water, and chemical corrosion.

3. Adhesion to Steel Substrate:

   Glass-Fused-to-Steel (GFS): GFS provides superior adhesion to the steel substrate because the enamel is fused with the steel during the firing process. This fusion creates a molecular bond, ensuring long-term adhesion and preventing delamination.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings have excellent adhesion to the steel substrate when applied correctly. The fusion bonding process ensures strong adhesion and prevents the coating from peeling or flaking off the steel surface.

4. Temperature Resistance:

   Glass-Fused-to-Steel (GFS): GFS has excellent temperature resistance, making it suitable for a wide range of applications, including both high-temperature and low-temperature environments. The glass enamel can withstand temperatures ranging from -40°C to 500°C (-40°F to 932°F) without degradation.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings are limited in their temperature resistance compared to GFS. They are generally suitable for applications with operating temperatures up to 150°C (302°F). Beyond this range, the epoxy may begin to degrade and lose its protective properties.

GFS bolted tank with IC reactor

5. Impact Resistance:

   Glass-Fused-to-Steel (GFS): GFS offers excellent impact resistance due to the tough and durable nature of the glass enamel. It can withstand mechanical impacts and resist damage caused by external forces, making it ideal for applications in harsh industrial environments.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings provide good impact resistance but may be less durable than GFS when subjected to severe impacts or mechanical stress.

6. Abrasion Resistance:

   Glass-Fused-to-Steel (GFS): GFS coatings are highly abrasion-resistant, making them suitable for applications where the coated surface may come into contact with abrasive materials or conditions.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings also offer some degree of abrasion resistance, but they may not be as resilient as GFS in abrasive environments.

7. Flexibility and Coating Thickness:

   Glass-Fused-to-Steel (GFS): GFS coatings are rigid and inflexible due to the nature of the glass enamel. The coating thickness is typically uniform across the entire surface.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings can be applied with varying thicknesses, and the flexibility of the epoxy allows for some degree of conformability to irregular surfaces.

8. Installation and Maintenance:

   Glass-Fused-to-Steel (GFS): GFS coatings are factory-applied and require precision manufacturing and firing processes. Installation on-site involves bolting together the pre-fabricated steel panels. Maintenance is minimal and typically involves periodic inspections and cleaning.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings are applied on-site using specialized equipment. Surface preparation and application must be carefully executed to ensure proper adhesion. Maintenance may involve periodic inspections, touch-ups, or recoating in areas with damage or wear.

9. Applications:

   Glass-Fused-to-Steel (GFS): GFS is widely used in applications requiring long-term durability, such as water and wastewater storage tanks, biogas reactors, anaerobic digesters, and industrial storage tanks.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings are commonly used in pipeline systems for oil, gas, and water transportation, as well as in underground structures, such as pipelines and storage tanks.

10. Cost Considerations:

   Glass-Fused-to-Steel (GFS): GFS coatings are considered a premium option and may have a higher upfront cost due to the precision manufacturing and firing process. However, their long-term durability and minimal maintenance requirements can result in cost savings over the life of the structure.

   Fusion-Bonded Epoxy (FBE) Coated Steel: FBE coatings are generally more cost-effective than GFS, making them a popular choice for pipelines and underground structures. However, they may require more frequent maintenance and recoating over time.

Conclusion

In summary, both Glass-Fused-to-Steel (GFS) and Fusion-Bonded Epoxy (FBE) Coated Steel offer excellent corrosion protection for steel structures. GFS provides superior adhesion, temperature resistance, and impact resistance, making it suitable for a wide range of applications, including water storage, wastewater treatment, and industrial tanks. On the other hand, FBE coatings offer good adhesion, cost-effectiveness, and flexibility, making them suitable for pipeline systems and underground structures. The choice between GFS and FBE depends on the specific application, operating conditions, and budget considerations. Properly applied and maintained, both coatings can extend the life of steel structures and protect them from the damaging effects of corrosion.