Corrosion, the gradual degradation occurring due to a metal or metal alloy’s reaction with its surroundings, is akin to natural calamities such as earthquakes and floods in its potential for harm.
Metal corrosion can lead to costly and hazardous damage to various structures, from vehicles and appliances to bridges and public edifices. Unlike other natural disasters, however, we have established emerging methods to curb and avert corrosion, safeguarding people, assets, and the environment.
Factors in Corrosion Prevention
Several elements play a role in pinpointing the specific issue or solution for corrosion control, including:
- Environmental factors like soil resistivity, humidity, and saltwater exposure.
- The nature of the product being processed, handled, or transported.
- Desired longevity of the structure or component.
- Closeness to sources of corrosion.
Despite the complexity of these factors and the usual certainty of metal oxidation, corrosion is manageable through established and efficient techniques such as
- Material Selection and Design
- Protective Coatings
- Monitoring and Inspection
- Cathodic Protection
- Chemical Inhibitors
- Comprehensive Corrosion Management.
Selecting and Designing Materials
It’s crucial to consider corrosion prevention during the material selection phase of design, which can prevent various failures. The decision-making process involves considering factors like corrosion resistance, availability and cost of materials, mechanical properties, maintenance, compatibility, life expectancy, reliability, and aesthetics.
Proper system design, integral to material choice, should consider construction parameters, geometry for adequate drainage, electrical isolation of different metals, sealing of crevices, corrosion allowance, operational lifespan, and maintenance needs.
Advanced materials in material science, such as ceramics, high-performance metals, electronic materials, composites, polymers, and biomaterials, offer enhanced performance through engineered properties and specialized processing.
Protective Coatings
“50% of all corrosion costs are preventable,
with roughly 85% of these specific to protective coatings.”
Research by NACE International, now known as AMPP, indicates that around half of all corrosion-related expenses are preventable, with protective coatings playing a significant role. These coatings act as barriers against corrosion, wear, and moisture. Depending on the requirements, they can be applied in various ways, such as spraying, welding, plating, or manual application.
Materials in protective coatings include epoxies, polyurethanes, and other polymers for organic coatings and metals like zinc, aluminum, and chromium for inorganic layers. The application process typically involves three steps: a primer, a complete coating, and a sealant.
Monitoring and Corrosion Inspection
Inspections ensure that protective coatings are correctly applied, minimizing corrosion risks. This field focuses on corrosion control, application and inspection of paint, project management, and quality assurance. It involves assessing a structure’s current and potential future state, as well as its repair and rehabilitation needs. Effective coating inspection can result in significant corrosion cost savings industry-wide.
Cathodic Protection (CP)
CP is a method used to control metal surface corrosion by making it a cathode in an electrochemical cell. This can be done by introducing a current from an external source to polarize the surface negatively, protecting and extending the asset’s life.
CP systems are used for various metal-based structures, including pipelines, storage tanks, and concrete structures with metal reinforcement. Galvanized steel components are also protected using a zinc coating in another CP approach.
Chemical Inhibitors
Corrosion inhibitors reduce the rate of metal corrosion in a given environment by slowing down the chemical reaction. These inhibitors are added in small quantities to environments like acids, cooling waters, and steam, continuously or intermittently.
Inhibitors are a cost-effective alternative to more expensive materials. They can be used internally in carbon steel pipes and vessels and for protecting reinforced steel bars in concrete.
Corrosion Management
Preventing corrosion and minimizing its costs requires more than technology; it necessitates a proactive corrosion management strategy. According to a NACE study, the most successful companies in reducing corrosion impact integrate technical corrosion management plans into their overall systems, reaching every organizational level.
Engaging all employees in corrosion management ensures the implementation of strategies throughout the lifecycle of a product or facility, leading to significant long-term cost savings.
Where To Start?
For a comprehensive inspection of metal corrosion or inquiries about corrosion management, contact Elite 360 Construction. Our expertise ensures effective prevention and management of corrosion, safeguarding your assets.