Anticorrosive paints: application and operating period

Surface preparation

Metal. It is recommended to do abrasive-blast cleaning of surface up to 1 or 2 degree under GOST 9.402-2004 (Sa 2 1/2 or Sa 2 under ISO 8501-1:2007) before anticorrosive paint application. The abrasive-blast cleaning is the most effective way to prepare the surface for painting. The surface shall be free of oil, consistent lubricant and dirt, mill scale, corrosion, paints, and foreign particles, during inspection without magnifiers. Any remained contaminants shall be like slight spotted or stripy coloring. The surface shall be rough for better coating-metal adherence.

If the abrasive-blast preparation of surface is not possible, for example, in case of existing production reconstruction, manual and mechanical tools can be used to clean the surface up to 3 degree under GOST 9.402-2004 (St 3 or St 2 under ISО 8501-1:2007). In this case, the primer tolerable to surface preparation shall be applied.

Concrete. Painting of concrete shall be applied 28 days after placing. Concrete surface prepared for anticorrosive coating shall not have protruding fittings, cracks, pot-holes, popouts, overlaps, arris spalling, oil stains, dirt, and dust.

Application

Three types of anticorrosive paint application: plant painting, field painting, and mixed painting scheme, which is expected the primer application in plant and painting in building site.

Materials' technical data and overlapping time are important for every painting. For example, anticorrosive paints applied at low temperature are more preferred in building site. Fast-drying paints - in plant.

Minimum and maximum overlapping time is important for existing production repair and at mixed painting scheme. It is help to avoid interlayered contamination with salt or liquid production environment condensate, during drying, and corrosion damages.

Coating working life

Protective coatings have high operating period – more than 15 years – under ISO 12944. Durable anticorrosive paints ensure such working life of materials. The average operating time is from 5 to 15 years. And low coating usage is up to 5 years.

Materials of different type and suitable thickness provide required operating period.

One primer can be applied for non-aggressive environments. More complex coating systems are recommended to be applied for constructions exposed to aggressive climate and technology factors. Primer and finishing enamels ensure high-quality durable protection of metal/concrete against corrosion and required decorative appearance.