A Sacrificial Anode Corrodes First to Protect Boat Metals An introduction to sacrificial anodes: A sacrificial anode can be defined as a disposable metal that is attached to the underwater or underground metals to prevent them from corroding. The term sacrificial is used because this anode corrodes first, thus sacrificing itself. In the marine industry, where underwater metals and other structures such as barges and tanks are constantly exposed to caustic sea water, the significance of these anodes comes into play. Know how anodes function: The principle on which these anodes function is very simple. When two dissimilar metals come into contact under water, there is a naturally occurring current of electricity that passes between these two metals. Owing to this, the metal that is more active corrodes owing to this constant electric current. Now, let’s bring an anode into the picture. This anode is made of a material that is most active among the metals in question. Since this is now the most active metal in the circuit, it will corrode first, saving the other metals from the adverse effects of corrosion. Zinc anodes are among the most commonly used by mariners. In fact that’s precisely why they are simply referred to as boat zincs. Precautions to be taken: However, as the sacrificial anode starts to corrode, it reduces in size. Once the anode has reached a particular size, it needs to be replaced with a new unit. This will ensure that the corrosion protection cycle carries on uninterrupted. If your anode has corroded and you fail to replace it, there is no safety barrier between sea water and your expensive boat metals. Hence, carrying out periodic checks about the efficacy of boat zincs is extremely important. This task can be carried out by a diver, or you can do it yourself provided you have the right experience in diving underwater. Choosing the most appropriate product: Today, a number of boat and vessel owners prefer to shop online for boat zincs. By purchasing directly from an authorized distributor, it is easier for you to avail competitive prices on your anodes. In addition to zinc, magnesium and aluminum anodes are also used. By seeking the professional advice of an anode manufacturer or dealer, you can determine the anode that best suits your requirements. Once the magnesium, aluminum or zinc anodes reach around 40% to 50% of their original size, you know it’s time to replace them. The use of sacrificial anodes assumes significance in systems where a naturally occurring static charge is created owing to free flowing liquids. This static charge usually occurs in a watercraft,
sea water, and pipelines. You can protect different types of structures such as marine boats and vessels, barges, tanks, dams, pipelines, and even underground metallic structures. Interestingly, there is a wide variety of anodes meant to be installed on different parts of a marine vessel to prevent it from corrosion.
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