Sacrificial Anodes
Aluminum Anode Alloy Compositions

Deep 7 Logo

The Deep7 aluminum alloy was designed as an effective, offshore alloy, for use in cold, deep water environments. The low Iron (Fe) content of the alloy ensures that it activates in lower temperatures and protects the platform or pipeline it is connected to for the designed life of the cathodic protection system.

Deep 10 Logo

The Deep10 aluminum alloy was designed as an effective, general purpose offshore alloy, for use in tropical water environments.

Aluminum Anode Chemical Composition


Alloy Type
Iron (Fe) 0.07 max 0.10 max
Silicon (Si) 0.10 max 0.10 max
Copper (Cu) 0.003 max 0.006 max
Zinc (Zn) 4.75 - 5.25 2.0 - 6.0
Indium (In) 0.015 - 0.025 0.01 - 0.05
Titanium (Ti) 0.025 max 0.025 max
Others (each) 0.02 max 0.02 max
Aluminum (Al) remainder remainder

Electrochemical Properties


Alloy Type
Open Circuit Potential (-) 1.08 V vs Ag/AgCl sw. (-) 1.08 V vs Ag/AgCl sw.
Closed Circuit Potential(1) (-) 1.05 V vs Ag/AgCl sw, (-) 1.05 V vs Ag/AgCl sw,
Seawater Capacity @25C 1100 A-Hr/lb. (2420 A-Hr/Kg.) 1100 A-Hr/lb. (2420 A-Hr/Kg.)
Seawater Capacity @ 5C 1100 A-Hr/lb. (2420 A-Hr/Kg.) Variable (2)
Seabed Mud Capacity (3) 950 A-Hr/lb (2090 A-hr/Kg.) 950 A-Hr/lb (2090 A-hr/Kg.)
Seabed Mud Capacity @ 5C 950 A-Hr/lb (2090 A-hr/Kg.) Variable (2)

Physical Properties


Alloy Type
Alloy Density 0.098 lb/in3 (2.71 gm/cm3) 0.098 lb/in3 (2.71 gm/cm3)
Cost Ratio Low Iron (Fe) Aluminum
(Al) Ingot < 0.05 Fe		 Normal Grade Al Sows
Raw Material & Conversion 1.10 1.00

Recommended Applications


Alloy Type
Offshore Structures (Platforms, Pipelines, FPS, FPSO, MODU, SPAR, Subsea Structure, Risers, Wind Turbine, etc) Any Ocean. Any Depth. Any Temperature. Any Tropical Ocean < 600 fsw (180 Msw) with mean water temperature higher than 45 F (7C).
Inshore Structures (Ports, Harbors, Jetties, Wind farms, Locks, Dams, Bridges, Piers etc.) Any Body of Water, Any Depth, Any Temperature with Chloride Ion Concentration > 12 ppt. Resistivity < 200 ohm-cm. Any Body of water < 600 fsw (180 Msw) with mean water temperature higher than 45 F (7C), Chloride Ion Concentration > 12 ppt. Resistivity < 200 ohm-cm.
Produced Water Vessels & Tanks Any produced brine < 140 F(60 C)(4). No improvement over Deep 10 alloy. Any produced brine < 140 F(60 C)(4)
Seawater Ballast Tanks Suitable for most seawater applications (5). No improvement over Deep 10 alloy. Suitable for most seawater applications (5).
1 - Recommended number to use when designing CP systems.
2 - Activation can be a problem with chemistries at extremes of specification in cold water.
3 - Recommended number to use when designing CP systems for offshore pipelines using bracelet or sub bottom anode systems.
4 - Consult a CP Specialist for guidance at elevated temperatures as performance de-rating will be needed.
5 - Exercise care with variable ballast tanks as dangerous volumes of hydrogen can be generated under certain conditions.
For additional guidance in application of these alloys, please contact Deepwater.