ANODE SHAFT 30 MM ALUMINUM

Function and technical context

Shaft anodes are cathodic protection elements designed to be mounted directly on the tail shaft of the vessel, acting as a sacrificial metal that absorbs electrolytic corrosion before it affects the shaft, propeller or metal components of the propulsion system. Made of aluminum alloy, this anode is especially indicated for navigation in salty and brackish waters, where galvanic corrosion is more aggressive and can quickly degrade submerged metals. The 30 mm diameter guarantees a precise fit on shafts of that nominal size, ensuring direct electrical contact and effective protection of the entire submerged propulsion area. Without proper cathodic protection, the stainless steel or bronze shaft is exposed to electrolysis, which can lead to pitting, progressive erosion and, in severe cases, shaft breakage while sailing.

When to replace this part?

The clearest sign that the shaft anode needs to be replaced is when it has lost between 30% and 50% of its mass, presenting an irregular, whitish or disintegrated surface; If the anode appears intact after a season, it may indicate that it is not making correct electrical contact and the cathodic protection is null. It is recommended to inspect and replace the shaft anode at least once per nautical season, coinciding with the annual beaching, or more frequently in areas of high water conductivity or marine areas with dispersed electrical currents. Renewing the anode preventively at each stranding is the most economical measure to avoid replacing the shaft or propeller, interventions that can involve much higher costs and leave the boat immobilized.