Auto parts electrophoretic painting line EDP KTL

The electrophoretic coating process, better known as E-coat, consists of the immersion of parts in a water-based solution containing a paint emulsion. Once the pieces have been immersed, an electrical current is applied, this generates a chemical reaction that causes the paint to adhere to the surface. A uniform layer is formed in the piece since the parts to be painted remain isolated, which prevents them from acquiring a greater thickness of paint.

Widely used in the general engineering sector to apply primer or protective coatings, electrophoretic coating, electropainting, electrodeposition, electrophoretic deposition (EPD), or e-coating, are all titles for a process which applies a thin, durable, and corrosion-resistant epoxy resin coating to metal components.

There are numerous benefits to electrocoating, including cost efficiencies, line productivity and environmental advantages. The cost efficiencies in electrocoat are higher transfer efficiency, precise film-build control, and low manpower requirements. Increased line productivity in electrocoat is due to faster line speeds, dense racking of parts, non-uniform line loading, and reduced human fatigue or error.

The environmental advantages are no- or low-VOC and HAPs products, heavy metal-free products, reduced exposure of workers to hazardous materials, reduced fire hazards, and minimum waste discharge.

Clean the surface
Oil, dirty and other residue that may prevent the adhesion of the e-coat. Therefore, the surface needs to be cleaned properly before going any further. The type of cleaning solution used will vary based on the type of metal. For iron and steel, an inorganic phosphate solution is usually preferred. For silver and gold, alkaline cleaners are very common.
An ultrasonic cleaner is the perfect tool for this job. This tank uses mechanical vibrations to create soundwaves in water or cleaning solution. When metal objects are placed in the solution, the bubbles created by the soundwaves will clean even those hard-to-reach places.

Rinse
Once the item is completely free of all dirt and scratches, it should be rinsed in distilled water and neutralizer. This will help remove any residue caused by the chemicals used in the cleaning procedure. This step should be repeated a few times to ensure that the item is free from any impurities. That way, you’ll have a better chance for successful adhesion during the e-coating process.

Wetting agent dip
Some E-coat manufacturers recommend a wetting agent dip in the tank immediately before the E-coat tank. This is typically to prevent bubbles from adhering to the parts as they go into the e-coat tank. Any bubble attached to the part surface will prevent E-coat deposition and will cause a paint defect in the finished part.

E-coating solution
When you’re completely sure that the item has been thoroughly cleaned, it’s time to submerge it in the e-coating solution. The chemicals used in the solution will depend on a few things, such as the type of metal that the item is made of.
Make sure that the entire item is submerged. This will ensure an even coating on every inch of the item, including those crevices that are difficult to reach. Electrical currents running through the solution will result in a chemical reaction that fuses the coating to the metal surface.

Cure the coating
Once the item is removed from the e-coating solution, it’s baked in the oven. This results in the hardening of the coating to ensure durability, and also creates a glossy finish. The temperature at which the item should be cured will depend on the chemistry of the e-coating solution that was used.