Surfaces

Corrosion protection in metallurgical and chemical operations is crucial for ensuring the long-term durability of equipment, operational safety, and reducing maintenance costs. In these demanding environments, materials are exposed to high temperatures, aggressive chemicals, moisture, and mechanical wear, which accelerate corrosion processes.

Main Types of Corrosive Influences:

Chemical corrosion – Caused by the action of aggressive chemicals (acids, alkalis, salts).
Electrochemical corrosion – Occurs in the presence of an electrolyte (e.g., moisture, water).
High-temperature oxidation and sulfidation – Typical in metallurgical operations.
Atmospheric corrosion – Mainly in cases of poor ventilation and high humidity.

Methods of Corrosion Protection:

Selection of Suitable Materials
- Stainless steels – Resistant to oxidation and chemical corrosion.
- Titanium, Hastelloy, Inconel – Used in extremely corrosive environments (e.g., in the chemical industry).
- Plastics and composites – Suitable for some chemicals and lower temperatures.
Surface Treatments and Protective Coatings
- Galvanic coating – Zinc (galvanizing), nickel, chromium.
- Metallization – Spraying metal layers (e.g., Zn, Al).
- Coatings – Epoxy, polyurethane, bitumen, or fluoroplastic paints.
- Ceramic and glass coatings – Highly resistant to acids and heat.
Cathodic and Anodic Protection
- Cathodic protection – Using sacrificial anodes (e.g., Zn, Mg) or external current.
- Anodic protection – Controlled passivation of the material surface (e.g., for aluminum or stainless steels).
Design Measures
- Suitable equipment design for liquid and condensate drainage.
- Protection of welds and joints.
- Good access to surfaces for maintenance.

Specific Requirements:

Metallurgical operations: High-temperature protection, resistance to oxidation, and mechanical stress.
Chemical operations: Resistance to a wide range of chemicals, gas and liquid diffusion.