Aluminum Tank Anode Featuring a Bent Rod Insert

Galvanic corrosion is a significant concern for the internal steel structure of a ship’s ballast water tank when exposed to seawater. When protective coatings degrade or fail, the most effective method to prevent corrosion in these tanks is through the application of sacrificial anodes.


The ship’s ballast water tank is prone to galvanic corrosion, particularly its internal steel structure submerged in seawater. To combat corrosion in the ballast tank, especially when coatings degrade or fail, sacrificial anodes are essential.

The prevalent anode type used for cathodic protection in vessel tank systems is the aluminum tank anode with a double cranked rod core. This anode variant is suitable for both new vessels and as replacements for old vessel anodes.

Quality Substrate Material
Crafted from high-purity alloys with reduced iron content, our aluminum tank anode is engineered to comply with the GS EP COR 201 standard.

Element GALVALUM III DNV-RP-B401-2011 GS EP COR 201
Zinc (Zn) 2.0% ~ 6.0% 2.5% ~ 5.75% 4.75% ~ 5.75%
Indium (In) 0.01% ~ 0.02% 0.015% ~ 0.04% 0.015% ~ 0.02%
Silicon (Si) 0.08% ~ 0.2% 0.12% max. 0.06% ~ 0.12%
Iron (Fe) 0.13% max. 0.09% max. 0.12% max.
Copper (Cu) 0.006% max. 0.003% max. 0.003% max.
Cadmium (Cd) 0.002% max. 0.002% max.
Total Impurities 0.1% max. 0.1% max. 0.1% max.
Aluminum (Al) Remainder Remainder Remainder


Low Driving Voltage
The aluminum tank anode maintains stable performance in seawater and electrolytes with chloride ions due to its operating potential being controlled within the range of -1.05 to -1.10 volts compared to the saturated calomel electrode (SCE).

Technical Measurement Performance
Open Circuit Voltage (-V) 1.10 min.
Closed Circuit Voltage (-V) 1.05 min.
Current Capacity 1135 A.h/lbs (2500 A.h/kg)
Current Efficiency 90% min.
Consumption Rate 7.6 lbs/A·y (3.4 kg/A·y)


Much Lighter in Weight
Compared to zinc, the aluminum tank anode has a lower density, which makes it lighter and more manageable during installation.

Strict Quality Control
Our aluminum tank anode adheres to the rigorous guidelines of ISO 9001:2015 standards, guaranteeing that it is produced, examined, and evaluated with meticulous procedures to uphold exceptional quality.

Customized Configurations
Drawing from more than five decades of manufacturing expertise, Keeper Anodes offers tailored customization of anode shapes, dimensions, and lifespan to align with your unique requirements upon request.