The answer is simple, because there are many factors that can alter the cathodic protection and situates our boats into corrosion.
But…before starting… Do we really know what is cathodic protection?
The truth is that there is a lot of info on the Internet, however, many concepts are mixed and it´s not very clear what we do when we cathodically protect our boats… it is talk about electrolysis, anodes, galvanic couples … a tangle of information but, do we really know what we do when adding sacrificial anodes to our boats? Do we know what an anode is?
We will be clarifying these concepts in different entrances on this blog.
cathodic protection
The basis of cathodic protection is simple: To place the metal we want to protect into the immunity zone. Under this apparent simple idea, there are hidden quite complex concepts. Unlike paintings, which generally functions as a barrier and hinders oxidation, cathodic protection seeks to eliminate the tendency to corrosion. «Trend» is the key word here because cathodic protection works based on thermodynamics.
Potential is the parameter which indicates whether the metal tends to rust or not. Therefore, checking this parameter, it is possible to verify that our boat is in the immunity zone where no corrosion occurs. Potential is influenced by many factors, such as temperature, composition of the structure to be protected, impurities, the presence of electrons, protons, or different species, hence, many factors are involved. Any factor that was not taken into account during the design of protection, it can vary the potential and can initiate the boat into corrosion.
So, why not control this parameter on boats in order to verify that our boat´s cathodic protection is the appropriate one and in case of deviation, we could be able to correct the problem before it has any consequence?
That is the philosophy of IDN • Naval Research and Development´s devices.
How do we measure potential? Thanks to our control probe, it is possible to monitor the status of corrosion protection and ensure that everything works properly. If a deviation in cathodic protection occurs, it can be detected in real time giving to the owner of the ship a way to avoid any further consequences. Early detection produces great savings; no doubt about that. Instead of replacing completely the engine´s tail, you just need to replace an anode, a wire with an insulation fault or repair an electrical connection. There is a remarkable difference in reducing costs and avoid unpleasant surprises that keep us away from sailing during the few days that we have to enjoy it.
Most boats spend much time in port where they are subjected to the action of other vessels or to the port itself, but …what happens if a corrosion problem occurs when we are not in the boat? The answer is…NOTHING; IDN devices will send an SMS alarm to your phone so you can check your boat and correct the problem before any mayor consequence happens. Furthermore, if the problem comes from the port´s mains, you can solve it by clicking in your cell phone to “disconnect” the ship from port´s mains.
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