ANODE OGIVE ORVEA 81

Function and technical context

The Orvea 81 ogive anode is a cathodic protection element designed to be mounted on the tip of the ogive or bow cone of propellers and drive shafts on boats with outboard or inboard propulsion. Its main function is to act as a sacrificial anode, attracting electrolytic corrosion and protecting itself instead of the higher-value metal components of the transmission, such as the propeller shaft, propeller or the ogive itself. It works within the galvanic protection system of the shaft line, a critical system in any vessel that operates in salt or brackish water, where electrolytic corrosion acts especially aggressively on aluminum and bronze alloys. If this anode is completely consumed without being replaced in time, corrosion directly attacks the structural components of the transmission, causing irreversible damage to the shaft, propeller or hub, with the consequent high repair cost.

When to replace this part?

Sacrificial anodes should be inspected at least once a season and replaced when they have lost approximately 50% of their mass, without waiting until they are completely consumed. The symptoms of a depleted anode are visible: very reduced surface area, porous or fragmented appearance and, in advanced cases, the appearance of corrosion pits on the nose or adjacent shaft. It is recommended to replace the Orvea 81 ogive anode preventively at each annual grounding, since the cost of this component is minimal compared to repairing a shaft or propeller damaged by galvanic corrosion.