Goal

Many metal objects that are manufactured need to be finished with an attractive coat of paint. This finish is available in an endless variety of colours and gloss levels. A commonly used method of applying these finishes is powdercoating. In many cases, an initial electrocoating treatment can ensure the required protection against corrosion. (See “Electrocoating of metal parts”)

Applications

Types of metal: iron, cast iron, steel, stainless steel, aluminium, zamac (zinc, aluminium, magnesium, copper), etc.
Products: car parts, truck parts, electrical appliances, frames, various metal constructions, etc.

Method

Powder coating is achieved using automatic spraying machines and spray pistols to apply powder paint to the product electrostatically. This is done in large spray chambers into which specific support tools bring the products on a transport system. This then involves several process stages:

Pre-treatment: power wash in a spray tunnel
Iron phosphating: optional, if iron products still need an anti-corrosion layer
Electrostatic application of the powder coating using automatic spraying machines
Baking on the powder layer in an oven
Cooling off
Quality control
Packing

The powders used are based on epoxy and/or polyester, and exist in virtually all colours and gloss levels. The correct quality of powder is selected depending on the part’s function. Powdercoating is an extremely environmentally safe painting technique because it uses recovery and recycling systems to ensure that no harmful substances are released into the environment.