What is the minimum negative shift that cathodic protection systems must maintain?

When discussing cathodic protection systems, the requirement for a negative shift is crucial for effectively preventing corrosion on metal structures. A minimum negative shift of 200mV is established as necessary to ensure that the protected metal is adequately polarized. This level of polarization indicates that the metal is sufficiently cathodic relative to its environment, which is essential for the effective functioning of the cathodic protection system.

Achieving this 200mV shift helps to provide a robust measure of protection by ensuring that the electrochemical potential of the metal structure remains low enough to impede corrosion processes. The shift reflects the change in potential that must occur when a cathodic protection system is applied, which is vital for mitigating corrosion risks in marine environments where metal structures are exposed to electrolytic environments.

Understanding that the minimum negative shift is set at 200mV helps maintain a consistent standard across the industry, thereby facilitating effective corrosion prevention strategies in marine applications.