Powder Coating Application

Powder coating application consists of three main steps.

Cleaning and pretreatment
Powder coating application
Baking
Cleaning and pretreatment

In order to get perfect results from the painting process, the part to be painted must be cleaned and pre-treated. There are various methods used in parts cleaning. While acidic cleaners work well for inorganic impurities, alkaline cleaners are more suitable for organic impurities. Degreasing chemicals are used for other organic impurities.

Phosphating is usually required after this cleaning process. However, passing through chromic acid solution gives better results for aluminum profiles used for architectural applications.

Paint Application

Powder coating is applied by means of an electrostatic gun. There are two types of guns for this purpose, corona and tribo. In the Corona type gun, while the powder leaves the gun, it is electrostatically charged negatively thanks to a high voltage electrode at the tip of the gun. Since the part to be painted is grounded, the electrostatically charged paint easily adheres to the part. However, sometimes the Faraday effect may occur in very indented and protruding parts and the entrance of dust into hollow areas may be problematic. In these cases, tribo type guns are used. In this type of gun, the paint is loaded with positive load only by friction without applying high voltage.

Baking

The powder coated part is put in baking. At this stage, the part is exposed to the time and temperature given in the properties of the paint. Paint cures at this temperature after melting and forming a smooth surface. At the end of this period, the painting process is completed after the part is taken out of the oven. Powder Coating products generally cure at 200 degrees in 10 minutes. However, the 10-minute period mentioned here starts after the piece reaches 200 degrees.