ANODE DISC 70 MM

Function and technical context

This 70 mm disc anode acts as active cathodic protection for the hull, shafts, propellers and submerged metal structures of the vessel, sacrificing itself electrochemically to prevent galvanic corrosion from damaging the most expensive components of the propulsion assembly and hull. It works within the passive anti-corrosion protection system, being the element that absorbs the degradation caused by the difference in electrical potential between different metals in contact with salt or brackish water. Its absence or depletion leaves materials such as bronze, stainless steel or aluminum exposed to accelerated deterioration that can compromise tail shafts, flanges, horns and hull surfaces in a few weeks of sailing.

When to replace this part?

The clearest symptom that the disc anode has completed its useful life is the visible reduction in its mass: when it has lost between 50% and 70% of its initial volume, it must be replaced without delay, since it loses protective effectiveness exponentially from that point on. It is recommended that the anodes be inspected and replaced at least once a season, or more frequently if the boat remains in areas of high electrical conductivity in the water, such as marinas with high traffic or waters with high salinity. Changing the anode preventively at each grounding is the most economical practice to avoid galvanic corrosion in high-cost parts such as shafts or propellers.