Corrosion control
Corrosion is a natural process - gradual destruction of metals is inevitable. However, corrosion can be slowed down and the life of metal structures can be prolonged by 40-50 years, which can save millions for your company.
What is corrosion control?
It is the prevention of natural destruction of metals. We applicate engineering principles and procedures to minimise corrosion to an acceptable level.
Can we eliminate corrosion completely?
Yes, we can, but it is rarely practical or economical to do so.
HOW WE DO IT?
There is a few methods to protect assets from corrosion. In practice, one or more of the following methods would be applied:
Design
Good design of equipment and fabricated steelwork eliminates the corrosion cells.
MATERIAL SELECTION
We can use materials with a high corrosion resistance to the environment. The selection is based on many factors: cost, mechanical strength, ease of production, welding, bimetallic corrosion etc
ENVIRONMENT CONTROL
We can modify the environment to reduce its corrosiveness by eliminating or neutralising the corrosive elements.
BARRIER COATINGS
We insert an insulating barrier to minimise contact between the metal and the electrolyte, which reduce the flow of corrosion currents. If it were possible to provide a perfect coating, then corrosion could be eliminated. However, it is not practical to achieve perfection due to the limitations of materials commercially available, construction practices and of course – cost.
CATHODIC PROTECTION
Cathodic protection prevents corrosion by converting all the anodic (active) sites on the metal surface to cathodic (passive) by supplying current or free electrons. An external current is usually applied via independent anodes, which are more active and corrode easier than the protected metal.
When the amount of current is properly applied, it will overcome corrosion from all the anodic areas on the pipeline/jetty/bridge and the structure will be cathodically protected.