RU   EN

Anticorrosive processing of metal constructions and tanks

Anticorrosive processing of metal constructions and tanks consists of three basic stages: surface processing, a first coat and painting of a metal surface. Coupling (adhesion) of the first layer directly depends on quality of refinement of a surface. Before painting we conduct following kinds of preparation of a surface: sand-sprinkler preparation (shot-blast), the hydrojet preparation and manual mechanized preparation. Application of this or that kind of processing of a surface depends from: 
1) economic feasibility of application of a certain kind of processing of a surface for the concrete client;
2) availability of one or another restrictions on object;
3) object sites (indoors, in open space, etc.).

At sand-sprinkler preparation (shot-blast) treatment we use the compressor equipment of the Japanese production of company the “Airmann” and shot-blast complexes of German company the” Kiess”. The principle of work of this equipment is based on giving of a stream of the filtered dry abrasive (metal fraction) under a high pressure on a metal surface. Application of this method of processing is the optimal under many factors: allows to achieve complete removal of all products of corrosion from a metal surface, ensures a required roughness of a surface that creates perfect conditions for the best coupling of an anticorrosive material with a metal surface.

At hydrojet treatment the water delivery principle under a high pressure on a cleared surface is used. We use high pressure units the "Karcher". This method is sparkless and allows to perform works on the filled tanks, is more economic variant in comparison with sand-sprinkler refinement and the optimal in places where sand-sprinkler refinement is impossible because of features of the object.
The mechanised (manual) processing means surface refinement manually, by means of the manual mechanised equipment (grinding machines, brushes, scrapers, etc.). This method is the most economical.

About standards of preparation of surfaces 
These standards are used by manufacturers of paint and varnish materials, describing technology of preparation of a surface before colouring and material drawing. Most often there are three standards of preparation of a surface. Their developers are:
• The National association of engineers on corrosion problems (NACE);
• Advice on colouring of metal constructions (SSPC);
• The Swedish association of standards (Sa, St).
Originally standards on surface preparation have been developed by the Swedish institute on corrosion problems. These organisations have developed following standards of preparation of a surface

National association of engineers on corrosion problems (NACE).
• NАСЕ 1 Clearing to pure metal;
• NACE 2 Clearing to almost pure metal;
• NACE 3 Commercial clearing.

Advice on colouring (SSPC).
• SP-1 refinement by means of solvent;
• SP-2 refinement by means of manual instruments;
• SP-3 refinement by means of the mechanised instrument;
• SP-4 Thermal refinement;
• SP-5 refinement to pure metal;
• SP-6 Commercial refinement;
• SP-7 Deleting refinement;
• SP-8 Treatment;
• SP-9 refinement after sandblasting;
• SP-10 refinement to almost pure metal.
The Swedish association of standards (Sa, St).
• St 2 refinement by the manual instrument; 
• St 3 refinement by the electric instrument;
• Sa 1 Deleting refinement;
• Sa 2 Commercial refinement;
• Sa 3 refinement to pure metal.