Protect your valuable investment with a complete Corrosion Survey to ensure that your vessel’s cathodic protection system is working properly.

This survey is conducted with the vessel in the water. We will measure the electrical voltage on all below the water-line metal parts and fittings to ensure that all equipment is properly bonded and has sufficient cathodic protection from Galvanic Corrosion.  The vessel is also tested for Stray Current corrosion which can come from the vessel’s own electrical system, from the dock where the vessel is berthed, or even from nearby vessels.

All dissimilar metals corrode in saltwater, due to Galvanic Corrosion, but this corrosion of a vessel’s metal parts can be controlled through the employment of sacrificial anodes such as “zincs”.  Likely places to place such anodes would include shafts, rudders, outdrives, engines and trim tabs.  These anodes, in order to protect your vessel’s metal parts, must then be properly connected to a complete bonding system that runs throughout the vessel.  All metal fittings and machinery, including but not limited to, all thru hulls, engines, propulsion gear, generators, batteries, pumps, fuel tanks with respective fill valves and vents, shafts, and basically all metal located below the water line need to be connected to, or be part of,  the vessel’s cathodic bonding system.

If two dissimilar metals in an electrolyte (Galvanic Corrosion) creates a low voltage DC current that can wreck unprotected metals in a matter of months, what would happen when a direct 12 volt current from your battery finds its way into your bilges and comes in contact with metal?  The resulting corrosion is called “Stray Current Corrosion” and can completely destroy a piece of metal in a matter of days or even hours!  Stray Current is the reason that DC wires should always be well above bilge water levels.  (AC wires must also be kept well away from the bilges.  Although they don’t normally cause corrosion, AC wires in water pose a dangerous shock hazard.)

Voltage values, bonding issues, condition of sacrificial anodes, and other observations will be documented with recommendations provided.