ANODE SHAFT 30 MM

Function and technical context

The shaft anode is the sacrificial element responsible for protecting the tail shaft of the boat against galvanic corrosion, a phenomenon that occurs when different metals come into contact in an electrolytic medium such as seawater or brackish water. This component works within the transmission line cathodic protection system, acting as an active pole that oxidizes in a controlled manner to preserve the integrity of the shaft, horn and adjacent metal components. With a diameter of 30 mm, the CMX-30 is sized to be installed directly on propulsion shafts of that size, being fixed using tightening screws that guarantee stable electrical contact. Without effective cathodic protection, the stainless steel or bronze shaft is exposed to pitting and corrosion that can compromise the tightness of the stuffing box and the alignment of the drive assembly.

When to replace this part?

The clearest sign that the shaft anode has reached the end of its useful life is a reduction in mass by more than 50%, indicating that it no longer offers sufficient protection; At this point, the shaft may begin to show superficial pitting or a dark discoloration characteristic of electrolytic corrosion. It is recommended to inspect the shaft anode at the beginning and end of each nautical season, and replace it preventively whenever it exceeds that level of wear or at least once per season in high salinity waters. Replacing the anode before it is completely depleted is the most economical measure to avoid damage to the shaft, horn and seals, which are considerably more expensive to repair or replace.