Epoxy powder coating facilities is just one example of the many different industrial coating systems we can install on your site. td finishing often get asked to support a client with their specialist coating needs. Several of our recent installations have included a fusion bonded epoxy (FBE) coating system. FBE coating is a protective coating of thermoset polymer, typically applied between 250 to 500µm.
Fusion Bonded Epoxy Coating
Whilst not a new technology, vast improvements have been made in this type of coating, since its introduction in the 1960’s. Thicker than a standard powder coating, this finish provides high chemical and abrasion resistance. It is a premium choice where performance of coating is key. In order to guarantee optimal coating is achieved, td finishing has developed many specialist systems. These systems have ensured consistent, high-quality production output.
How does fusion bonding epoxy work?
In a typical FBE system, the material substrate is heated to between 180-250°C. When the coating is applied, the high temperature causes the resin and hardener to react with heat, flow into a liquid and then harden. This is caused by a process of chemical cross-linking, known as fusion bonding. The product is then post cured in a second oven, running between 180 and 200°C.
For the FBE coating process, first the substrate is cleaned and prepared in the spray or dip pre-treatment system. It is then placed into a combined drying and preheat oven. This oven is used to raise the product temperature to the powders exacting requirements. Once pre-heated to the desired temperature, the component passes to the application area. This can take the form of an automated system, manual spray booth or where required, a fluidised bed dip tank. The pre-heat temperature, cooling rates and transfer times between these two stages, along with the powder application, are critical to achieving a high-quality FBE finish.
Curing FBE in a Powder Curing Oven
Where the FBE coating is a stand-alone coating, the components are post cured following powder application. However, when an additional decorative coating is to be applied, the substrate is first allowed to cool. Then, a more conventional polyester powder coating is applied. The components are then transferred to a curing oven between 180-200°C, with a variable dwell time. This time is dependant on the substrate material thickness.
Fusion Bonded Epoxy Powder Coating Facilities
In two recently delivered fusion bonded epoxy powder coating facilities, the clients required very different products be coated, with an FBE coating. The first plant for mild steel tanks required a 3-stage pre-treatment system, with Demin water rinse. As well as drying and curing ovens. The second system was utilised for the coating of large copper busbars. It involved an indexing conveyor, indexing pre-heat oven, automatic drop-section, FBE fluidised-bed dip-tank and a post-curing oven with automated pneumatically powered doors.
Power and Free Conveyor Systems
Both systems required very specific and variable control parameters, which varied across the entire product range. td finishing chose, in this case, to utilise power & free (P&F) conveyor systems. Power & free allows for more complicated, precision control of coating processes – as opposed to a traditional monorail conveyor. All while minimising the footprint requirements of the facility. For sheet heating and curing, the P&F system allows for the processing of 2mm to 12mm sheets, within the same system. For the busbars, it was possible to transfer the flightbar to an automated drop section and into the fluidised bed within a very specific time limit. This ensures the products could be transported into the fluidised bed, and agitated within the specified time limits.
Contact Us Today
Not sure how to achieve your finishing requirements? To find out more about investing in powder coating facilities for your business, head to our website today. Or, you can call 0121 520 8884 or email email@example.com to speak to a member of our helpful and friendly team.
If you have found this blog helpful, you may wish to read our previous blog on Powder Curing Oven Installations.