ANODE SHAFT 45 mm.

Function and technical context

The shaft anode is the sacrificial element responsible for protecting the tail shaft of a vessel against galvanic corrosion produced by the electrolytic action of sea or brackish water. This component is mounted directly on the propulsion shaft, acting as the negative pole of the galvanic cell and degrading itself to preserve more noble metals such as bronze, stainless steel or aluminum of the shaft and propeller. Without proper cathodic protection, the shaft is exposed to accelerated corrosion that can cause pitting, structural weakening and, in severe cases, breakage while underway. The CMC45EURO model is designed for 45 mm diameter shafts, with a zinc formulation suitable for salt and brackish water in accordance with European cathodic protection standards.

When to replace this part?

Shaft anodes must be inspected at least at the beginning and end of each sailing season, and replaced when they have lost approximately 50% of their mass, since below that threshold the cathodic protection capacity drops significantly. The clearest symptoms of a depleted or missing anode are the appearance of pitting or surface erosion on the propulsion shaft, visible corrosion on the horn mounts or the propeller, and in advanced cases, abnormal vibrations due to deterioration of the shaft. Replacing the anode preventively when beaching the boat is the most economical measure to avoid replacing the entire shaft or damaging the horn, considerably more expensive operations.