Sacrificial anode

The mechanism of the sacrificial anode protection system is very similar to the reaction mechanism of electrochemical cells. In sacrificial anodes the protected metal is placed on the cathode side and then a more reactive metal or alloy (having a larger potential difference than the protected metal) is chosen and connected to the protected metal as an anode. Sacrificial Anodes are highly active metals that are used to prevent a less active material surface from corroding. A galvanic anode is the main component of a galvanic cathodic protection (CP) system used to protect buried or submerged metal structures from corrosion.

Sacrificial anodes generally come in three metals: magnesium, aluminum, and zinc. Magnesium has the most negative electropotential of the three (see galvanic series, right) and is more suitable for on-shore pipelines where the electrolyte (soil or water) resistivity is higher.

A sacrificial anode of aluminum will add an anodic current to the system shifting the corrosion potential of the specimen to be protected (copper) towards a value that is more negative. In general, we can say that the part of the ship to be protected against corrosion is called parent surface or cathode, whereas the more reactive material covering on the ship’s part which acts as an anode is termed as a sacrificial anode. Any time you have two different metals that are physically or electrically connected and immersed in seawater, they become a battery. Is a Zinc Anode Really Necessary? There are a lot of variables that include the overall water chemistry and the types of metals in your pool system.

When is cathodic protection needed? How sacrificial anodes work. Marine structures are predominantly made of steel.

This makes them highly susceptible to corrosion. Seawater acts as an electrolyte, which causes a transfer of electrons from the steel structure through oxidation. The earliest experiments on cathodic protection were performed with zinc anodes that had been electrically connected to copper plates immersed in seawater.

All metals immersed in an electrolyte (sea water for example) produce an electrical voltage. What do sacrificial anodes do? Anode rods generally can last about three to five years but it really depends mostly on the quality of your water and how much water travels through your water heater. This procedure is essentially the same for most if not all gas and electric water heaters.

A war is raging under your boat. High-priced running gear and outboard lower units made of aluminum, copper, and steel face galvanic corrosion. Aluminum sacrificial anode alloy generates -1. Volts In order to provide protection, the highest practicable voltage difference possible is required between the sacrificial anode and the metal to be protected.

One type of cathodic protection system is the sacrificial anode. Zinc anodes , also known as sacrificial anodes , play a key role in the maintenance of your boat. The term “zincs” has become synonymous with sacrificial anodes , being that zinc was the original material used for this purpose. These days, anodes don’t have to be “zincs. Often, non-zinc anodes are actually the better choice.

Maintenance is an important part of owning a boat an depending on your environment, your sacrificial anodes may need to be checked and replaced fairly often.

Galvanic corrosion occurs when one metal causes corrosion in another metal because of differing potential voltages. Learn more about how a Sacrificial Anode Cathodic Protection system takes advantage of this natural phenomenon to prevent corrosion in valuable metal structures. Metec have one of the largest and diverse mould selections available covering all standard weld on hull anodes as well as adaptable mould tooling ensuring we can meet any client demand for weight, shape or size as well as ensuring flexibility of core extension for compatibility to any pre-existing doubler pads. How To Replace A Sacrificial Anode How To Replace A Sacrificial Anode.

Just about every storage water heater tank has a sacrificial anode rod and if you have one at home knowing how to replace a sacrificial anode for your storage tank hot water service is a very easy and simple job. We provide satisfied customers with the highest quality sacrificial anodes on the market.