Corrosion Protection of Structures
Corrosion protection of bridges, high-rise structures, offshore platforms, oil storage facilities, ship deck superstructures and other engineering structures exposed to aggressive environments is an important part of the industrial operation and maintenance of metal structures.
Direct irreversible metal losses caused by corrosion can amount to up to 10% of the total quantity of metal produced.
The company specializes in corrosion protection of structures and equipment exposed to aggressive environments, including alkalis, acids and other chemicals.
For structures and equipment operating at elevated temperatures, heat-resistant coatings with heat resistance up to 450 °C are also used.
Corrosion protection work includes several main stages.
1. Selection of the Protective Coating System
The coating system must provide the required level of protection, taking into account the operating conditions of the structure.
The coating system and required dry film thickness are selected according to the type and intensity of environmental exposure.
The selection of an appropriate coating system should provide an optimum balance between application cost and service life. An unsuitable or excessively economical system may result in premature coating failure and additional maintenance costs.
2. Shot Blasting and Sandblasting
Shot blasting or sandblasting, followed by degreasing and dust removal, makes it possible to:
- remove mill scale, rust, old paint and other contaminants from the surface;
- provide the required surface roughness and other surface characteristics;
- prepare the surface for subsequent painting, application of protective coatings or rubber lining;
- strengthen the surface layer of the structure.
3. Application of Protective Coatings
Protective coatings are applied to the internal and external surfaces of metal and concrete structures and facilities.
Particular attention is paid to joints, connections and structural details, as these areas are especially susceptible to corrosion.
Before applying the protective coating, the surface is thoroughly cleaned of contaminants to ensure strong and durable adhesion between the coating and the substrate.
When repairing existing structures, surface preparation is particularly important. The surface is:
- cleaned;
- freed from dust;
- degreased;
- primed;
- coated with the specified protective coating system.
Proper completion of all preparation and application stages helps maximize the service life of both the protective coating and the metal or concrete structure.
4. Quality Control of Protective Coatings
To achieve an effective and durable corrosion protection system, quality control at every stage of the coating process is essential — from inspection of materials and equipment to final acceptance of the completed coating.
Inspection and measuring equipment is used to monitor key parameters, including:
- measurement of dry film thickness (DFT);
- monitoring of application conditions — air temperature, surface temperature, relative humidity and dew point;
- assessment of coating adhesion to the substrate using the cross-cut test;
- measurement of prepared surface roughness;
- inspection of surface dust contamination before coating application.