Pretreatment refers to the process of thoroughly cleaning the scale, rust, grease, dust, and other dirt on the surface of the workpiece before coating, so as to ensure a firm bonding between the coating and the surface of the object to be coated, strong adhesion, and uniform coating layer, thereby achieving high-quality products, extending the product's service life, and improving the decorative properties of the coating.
Before coating, the cleaning process of removing various oil stains (such as lubricating oil, emulsion, grease, sweat stains, etc.), oxide skin, rust, and dust on the surface of the coated object to make the coated surface clean is an essential process in the pretreatment process before coating; The type of chemical pretreatment (or conversion film treatment) or mechanical processing pretreatment (such as shot blasting, sandblasting, etc.) to be performed on the clean coated surface (whether or not) depends on the substrate and surface condition of the coating, and the coating process requirements.
Chemical pre-treatment (wet): spray pre-treatment, tank immersion pre-treatment
Mechanical pre-treatment (dry): shot blasting pre-treatment, sandblasting pre-treatment