What is Galvanic Corrosion?
Water is a substance of a certain conductivity. When the salt and minerals in the water increase, the conductivity of the water increases indirectly. Therefore, the metal parts under water form a closed system transmission circuit among themselves due to the conductivity of the water.
Each metal has a different electron structure, potential, strength and hardness. While some metals are easy to give electrons, some metals are very difficult to give electrons. Metals that give easy electrons are considered soft. G
• Electrical leakage on the boat,
• The problem with the grounding system of the coastal connection,
• Grounding system error on the boat,
• Metal deposits in the seabed in the area,
• Surrounding metal scaffolding or marina systems,
• Electrical leakage in neighbouring boats,
• The body of the adjacent boats is made of metal or aluminium,
• The salinity level of seawater; may or accelerate galvanic corrosion.
Structures of Metals
The anode or cathode of metals underwater causes galvanic corrosion. Therefore, knowing the structure of metals will ensure that the necessary protections are made. Metals that are anodes give easy electrons and are easily corroded. We can call them soft metals. Such metals are used as anode for protection purposes in boats. He names them tutya. They are usually made of metals such as aluminum and zinc.
How many volts provide protection?
Every metal under water is activated at a certain voltage level. If the handles are installed for protection, the handles cannot provide protection in the form of a voltage that is contrary to the potential voltage of the handles. In this case, instead of holding, other metals, shafts, propellers, transmissions, tails, etc. under the boat cause the corrosion to drop.
For example, a handle made of zinc provides protection for transmissions between 0.9 and 1.1 Volt under water. When the runaway voltage rises and goes down, they can't provide protection.
What is a galvanic insulator?
Nowadays it is a product that is given as standard on many expensive boats but some brands still do not standard. They are used to protect boats against galvanic corrosion. The boats are fitted with a galvanic insulator on the grounding line of the charging cable from the beach. Leakage currents in the coastal tension, which are usually DC currents, are a tool that prevents them. Because the most important causes of galvanic corrosion in boats are charging electricity from the beach.
Leakage currents in long-term coastal cables will also accelerate the flow under water and accelerate the interaction of metals. Corrosion will occur as a result.
Therefore, it is recommended to use galvanic isalics for all boats that receive electricity from the beach.