Our E-coating process – start to finish
Following our look at the automated powder coating facility, this blog details our E-coating process from start-to-finish.
E-coating, also known as EPD or electrophoretic painting is a complete submersion process that is becoming increasingly popular due to its low cost and ability to easily coat complex or hard-to-reach areas evenly. E-coating can be used as a corrosion-resistant primer, or as a standalone process for parts that won’t be exposed to UV light, and is commonly used in the automotive sector for parts such as brackets and tow bars.
Our dedicated E-coat facility operates using a 12 stage process that includes a zinc phosphate pre-treatment and full immersion coating of the product. Similarly to our automated powder coating process, before parts can go through pre-treatment and coating, the surfaces need to be prepared through shot blasting or other methods.
Stage 1 – Degreaser
After being loaded onto the motorised track, parts are submerged in a tank of alkaline cleaner. This removes any contaminants from the surface of the product.
Stage 2 & 3 – Rinse
Parts then go through a 2 stage rinse to ensure no residue is present prior to pre-treatment.
Stage 4 – Conditioner
An activator is used prior to coating with zinc phosphate. This encourages crystal growth during the pre-treatment and helps to produce a finer phosphate finish.
Stage 5 – Pre-treatment
Zinc phosphate is then applied to the product to improve paint adherence and corrosion resistance.
Stage 6 & 7 – Rinse
A second two-stage rinse cycle is used to remove any phosphate residue.
Stags 8 – De-ionised water bath
Deionised water immersion is then used to remove any water-soluble materials from the product prior to coating.
Stage 9 – E-Coating
Once the pre-treatment process is finished, parts are ready to be coated. The parts are lowered into the electrically charged paint tank until fully submerged, causing the deposition of the e-coat paint onto the product.
Stage 10 – UF
Once E-coated, parts go through a 2 stage Ultrafiltration bath to remove any undeposited paint and collect excess to be reused.
Stage 11 – Oven curing
Similarly to the powder coating process, the coated parts then go through an oven curing process to harden the coating into a finished product.
Stage 12 – Quality check
The final stage is the quality check. Parts are examined for any visual defects with the finish, as well as the thickness of the E-coat being measured digitally to ensure adherence to the required specification. Once passed, parts are then packaged for delivery to the customer.
You can see some examples of our finished e-coating process below, or contact us today for your own personalised service.