ANODO POPA DISCO Ø 150 (ZN)

Function and technical context

The aft anode in 150 mm diameter disc format is a cathodic protection element designed to safeguard the hull stern, tail shaft, propeller and submerged metal components against galvanic corrosion. Made of high-purity zinc, it acts as a sacrificial metal: being electrochemically less noble than the stainless steel, bronze or aluminum from which the propulsion elements are made, the anode preferentially corrodes, protecting the most valuable structural parts. Its circular and flat geometry – disc format – facilitates installation on flat transom surfaces and transom plates, offering a uniform contact surface that guarantees optimal electrical conductivity with the hull or the structure it protects. Without adequate cathodic protection, galvanic corrosion can deteriorate the propeller shaft, the stern brackets, the engine tail body or the hull itself in critical areas, leading to high-cost grounding repairs.

When to replace this anode?

The clearest indicator that the zinc anode has reached its useful life is a reduction in mass of more than 50%: when the disc shows visible wear, a badly eroded irregular surface or has lost half or more of its volume, it should be replaced immediately. The standard recommendation in nautical is to inspect and renew the zinc anodes at least once per nautical season, preferably during the winter stranding, although in waters with high conductivity or in installations with eddy currents it may be necessary to replace them every six months. Replacing the anode preventively at each annual tune-up is the most economical measure to avoid corrosion damage to propulsion parts and aft structure that can involve repairs costing several thousand euros.

Compatibility table