In addition to the residue of oil on the surface of the workpiece, there are foreign bodies such as rust and oxide, which will seriously affect the adhesion performance, decorative performance and corrosion resistance of the coating after painting. Thoroughly removing these foreign bodies is a necessary condition to ensure good painting. For cold plate or galvanized plate without rust, only degreasing and oil removal clean can ensure the quality of coating, so we generally use alkaline degreasing agent for treatment; However, for rusted workpieces or hot plates, rust and oxide need to be removed, in this case, we can use mechanical rust removal or pickling rust removal, according to the production efficiency, steel parts requirements and environmental requirements to choose the appropriate rust removal method, pickling rust removal method is generally suitable for steel and metal materials with tensile strength requirements less than 1000MPa, such as rust removal of high-strength fasteners. Shot peening can be used instead of pickling. In addition, for some galvanized plates with fingerprint film resistance, the fingerprint film resistance may affect the coating adhesion. The fingerprint film resistance can not be removed by alkaline degreaser, and pickling is also needed.
Post time: Oct-24-2023