Cathodic protection (CP) is a technique used to prevent corrosion in metal structures by controlling the corrosion potential of the metal. It works by applying an electrical current to the metal surface to counteract the corrosion process.
CP is commonly used in a variety of industries and applications, including marine structures, pipelines, storage tanks, and industrial facilities. The technique is particularly useful for protecting metal structures in harsh environments, such as those exposed to saltwater or aggressive chemicals.
When investing in CP systems, there are some key considerations. Firstly, it is important to ensure that the CP system is suitable for the specific application and environment in which it will be used. Factors such as the size and shape of the metal structure, the surrounding environment, and the type of metal being protected all play a role in determining the most appropriate CP system.
Another important consideration is the type of CP system. There are two main types: impressed current and sacrificial anode. Impressed current systems use a direct current to counteract the corrosion process, while sacrificial anode systems rely on the corrosion of a more reactive metal (such as magnesium or aluminum) to protect the metal structure.
It is also essential to consider the type of maintenance required. Some systems require regular monitoring and maintenance, while others may be designed to be more self-sustaining.
And finally, cost considerations which involve upfront costs of installation as well as ongoing maintenance requirements. Whilst some CP systems may have higher upfront costs they can effectively be a long-term cost-effective solution by offering more durable and reliable protection against corrosion.
Cathodic protection is a critical tool for preventing corrosion in metal structures. So consider all the factors: suitability for your specific application; levels of maintenance required; and the short and long term cost of your selected protection system.
References:
- "Corrosion and cathodic protection"
- "Impressed Current Cathodic Protection Systems"
- "Sacrificial Anode Cathodic Protection Systems"