Steel components used in plumbing, water infrastructure and industrial facilities are exposed to some of Africa’s harshest operating environments, from coastal regions and industrial zones to municipal water networks and mining operations. Protecting these assets against corrosion is critical to extending service life, maintaining system reliability and reducing maintenance costs. One corrosion protection method is zinc metal coating.
Simon Norton, director of the International Zinc Association (IZA) Africa.
All images supplied by the International Zinc Association Africa
Steel structures across Africa are exposed to some of the world’s harshest operating environments, from coastal regions and industrial zones to mining operations and infrastructure projects. Protecting these assets against corrosion is critical to extending service life and reducing maintenance costs.
One corrosion protection method that continues to prove its value is zinc metal coating, a process in which molten zinc is sprayed onto a prepared steel surface to form a durable protective coating. Zinc metal coating, also called zinc thermal spraying, is achieved by feeding zinc wire into a specialised spray gun where the material is melted before being projected onto the steel substrate.
A robust barrier
Zinc metal coating provides long-lasting corrosion protection for steel infrastructure in demanding environments.
Melting can be accomplished either through combustion in an oxygen-fuel gas flame or by creating an electric arc between two zinc wires in the spray gun. Once applied, the zinc coating forms a robust barrier that protects the underlying steel from corrosion.
According to Simon Norton, director of the International Zinc Association (Africa), zinc metal coating offers several advantages for large-scale infrastructure and industrial applications. “Zinc metal coating provides long-lasting corrosion protection for steel structures that are often difficult or costly to maintain. The process is particularly valuable for infrastructure that is expected to deliver decades of reliable service under demanding environmental conditions,” explains Norton.
Large and complex steel components
Unlike some coating systems, thermally sprayed zinc coatings can be applied to large and complex steel components, making them suitable for bridges, transmission towers, industrial facilities, marine structures and mining infrastructure.
The performance of zinc metal coating is enhanced by the natural corrosion-resistant properties of zinc. Even if the coating is damaged, zinc continues to protect exposed steel through sacrificial action, helping to prevent rust from spreading.
Asset longevity and lifecycle cost management
As industries increasingly focus on asset longevity and lifecycle cost management, corrosion protection systems that minimise maintenance requirements become increasingly important. “Investing in effective corrosion protection from the outset can significantly reduce future repair and replacement costs,” adds Norton.
With its proven track record and versatility, zinc metal coating continues to play an important role in protecting steel infrastructure throughout Africa. “Zinc metal coat remains one of the most trusted technologies available for achieving this goal,” he concludes.
| About the International Zinc Association (IZA)
The IZA is the only global industry association dedicated exclusively to the interests of zinc and its users. Operating internationally and locally in Africa through the IZA Africa Desk, the IZA helps sustain the long-term global demand for zinc and its markets by promoting such key end uses as corrosion protection for steel and zinc as essential in human health and crop nutrition. IZA’s main programmes are Zinc Use Research, Sustainability & Environment, Technology & Market Development and technical Communications. In South Africa, the IZA plays a vital role in establishing the basis for the successful growth of the zinc industry by increasing awareness of zinc and its applications and benefits in key sectors and markets. |
