ANODE SHAFT 30 mm.

Function and technical context

The 30 mm shaft anode acts as a sacrificial element in the boat's cathodic protection system, being located directly above the tail shaft to intercept galvanic corrosion before it reaches higher value metal components such as the shaft itself, the propeller or the horns. Its operating principle is based on the electrochemical potential difference: being a more electropositive metal than stainless steel or bronze, the anode preferentially oxidizes, thus protecting the structural integrity of the propulsion shaft. Without adequate cathodic protection, the tail shaft can suffer from pitting corrosion or accelerated galvanic corrosion, compromising stuffing box tightness and transmission efficiency. The CMC-30 reference is specifically sized for 30 mm diameter shafts, guaranteeing firm electrical contact and a homogeneous distribution of protection throughout the area exposed to water.

When to replace this part?

The clearest sign that the shaft anode has reached the end of its useful life is a reduction in its mass by over 50%, indicating that it no longer offers sufficient protection; At that point, its immediate replacement is essential. As a general preventive criterion, shaft anodes should be inspected at least once per nautical season and replaced at each annual beaching, regardless of their visual condition, especially in salt or brackish water areas where corrosion is more aggressive. Renewing the anode preventively at each seasonal tune-up is the most economical measure to avoid costly damage to the propulsion shaft, propeller or stuffing box.

Compatibility