RECTANGULAR ANODE 147x65x22

Function and technical context

The rectangular sacrificial anodes act as cathodic protection on the hull, shafts, propellers and submerged metal structures of the vessel, attracting electrolytic corrosion towards their own mass and thus preserving the most valuable components. This 147x65x22 mm rectangular anode is made of zinc alloy, the reference material for boats in salt and brackish water, where the difference in electrochemical potential between different metals can destroy critical parts in a matter of months. Its function within the galvanic protection system is to act as a sacrificial electrode, being consumed in a controlled manner so that the rest of the metal structure remains intact. The absence or depletion of this component directly exposes the base metal of the hull, rudder blade, thru-hull or propeller to accelerated and irreversible corrosion.

When to replace this part?

The clearest symptom that the rectangular anode has completed its cycle is a mass loss of more than 50% compared to its initial size: when the zinc block presents a visible reduction, irregular surface or is practically consumed, the cathodic protection is no longer effective. The inspection of the sacrificial anodes should be carried out at least once a season, preferably at the annual winter beaching, although in waters with high conductivity or vessels with greater electrical activity on board a semi-annual inspection may be necessary. Replacing the anode preventively before it is completely depleted is the most economical measure to avoid damage due to galvanic corrosion to structural or propulsion elements, the repair of which can be considerably more expensive.