Sacrificial Anodes & Cathodic Protection

Complete Cathodic Protection Solutions from China

Every steel structure exposed to seawater needs cathodic protection. Whether it is a ship hull sitting in port, an FPSO unit stationed offshore for 25 years, or a wind farm monopile driven into the seabed, corrosion will attack unprotected steel at rates of 0.1–0.3 mm per year. Sacrificial anodes are the first line of defense — and as a dedicated sacrificial anode supplier, hicool delivers the right anodes with the right classification certificates, on time and at competitive pricing.

Our manufacturing partner is one of China's top sacrificial anode producers, established in 2006, with 17 years of continuous production experience. The factory operates 8 natural gas melting furnaces, maintains over 1,000 mold sets in stock, and runs an in-house chemical analysis lab and electrochemical performance lab — enabling daily output of 25 tons (aluminum) and 30 tons (zinc), totaling 6,000 metric tons per year.

Why Source Sacrificial Anodes Through hicool?

• Full classification coverage. DNV type approval (aluminum and zinc), BV form recognized certificate, CCS, LR, and ABS quality certificates. Every shipment includes material test certificates with chemical composition analysis and electrochemical performance data.
• Fast delivery. Small batch orders ship within 1–2 working days from existing mold inventory. Standard production orders deliver in 7–15 days. Large project quantities (100+ tons) are routine.
• In-house quality assurance. Chemical analysis lab (composition per GB/ASTM standards) and electrochemical performance lab (potential, capacity, dissolution rate, contact resistance). No dependence on external labs — full traceability from raw material to finished anode.
• Competitive pricing. Direct from manufacturer with no middleman markup. Combined with lower Chinese production costs, expect 30–50% savings versus European anode suppliers at equivalent quality and certification levels.
• Third-party inspection welcome. Classification society surveyors (DNV, BV, LR, CCS) regularly attend production. Buyer-appointed inspectors are accommodated at no additional charge.

When to Use Sacrificial Anodes vs. ICCP

Sacrificial anodes are passive cathodic protection — they corrode preferentially to protect the steel structure, requiring no external power source. They are the standard solution for commercial ship hulls, rudders, propellers, ballast tanks, and medium-sized offshore structures. Maintenance is straightforward: replace consumed anodes during scheduled drydocking.

ICCP (Impressed Current Cathodic Protection) is an active system using an external power supply to drive current through inert anodes (typically MMO or platinized titanium). ICCP is recommended for large vessels over 200m LOA, FPSOs, and complex offshore structures where sacrificial anodes alone cannot provide adequate current distribution across the entire wetted surface. Many large projects use a hybrid approach — ICCP for primary protection with sacrificial anodes as backup in critical or hard-to-reach areas.

The governing design standard for marine cathodic protection is DNV-RP-B401 (Cathodic Protection Design), supplemented by NACE SP0176 for fixed offshore structures and ISO 15589-2 for offshore pipelines.

Anode Alloy Selection — Zinc vs. Aluminum

Zinc alloy anodes are the traditional workhorse for ship hull protection. They offer stable, predictable electrochemical performance in normal seawater temperatures (below 50°C) and have been the default choice in commercial shipbuilding for decades. Key standards include US-MIL-A-18001J, ASTM B418-73 Type I and Type II, and GB/T4950-2002. Zinc anodes are typically used on vessel hulls, rudders, propeller shafts, and port infrastructure.

Aluminum alloy anodes offer approximately 3× higher electrochemical capacity (2,500+ Ah/kg vs. 780 Ah/kg for zinc), meaning significantly less anode weight is required for equivalent protection. This makes aluminum the preferred material for offshore platforms, deep-water structures, and subsea pipelines where weight and space are critical. Aluminum anodes also perform better in buried (mud zone) environments. Standards include GB/T4948-2002, DNV-RP-B401, NORSOK, PL742 (Greece), Impalloy III (France), and Galvalum III (USA).

High-temperature zinc anodes are specially formulated for environments above 50°C — such as heat exchangers, central cooling water systems, and diesel engine jacket water coolers — where standard zinc anodes suffer intergranular corrosion and rapid capacity loss. These anodes hold specific DNV type approval for high-temperature applications.

Applications We Serve

• Newbuild shipyards — hull cathodic protection, ballast tank anodes, sea chest anodes
• Ship repair and drydocking — anode replacement surveys to class requirements
• Offshore platforms and jackets — splash zone and submerged zone protection
• FPSO/FSO units — full cathodic protection anode packages including ICCP
• Port and harbor infrastructure — steel piles, sheet piling, jetty structures
• Cooling water systems — heat exchanger tube sheets, condenser water boxes
• Offshore wind — monopile and transition piece anodes
• Subsea pipelines — bracelet anodes per DNV-RP-F103

Standards Compliance

• Aluminum anodes: GB/T4948-2002, DNV-RP-B401, NORSOK, PL742, Impalloy III, Galvalum III
• Zinc anodes: GB/T4950-2002, US-MIL-A-18001J(1983), ASTM B418-73 Type I & II
• Management systems: ISO 9001 / ISO 14001 / ISO 45001
• Design reference: DNV-RP-B401, NACE SP0176, ISO 15589-2