Antaike Highlights: Zinc Consuming Fields-Part One Shipbuilding

When discussing downstream applications of zinc, we will first think about industries such as construction, home appliances and automobiles. However, amid a recovery in the global shipbuilding sector and accelerated advancement of green shipping, the marine segment is becoming a noteworthy zinc-consuming market.

Based on vessel anti-corrosion systems, we have recently systematically reviewed zinc usage in marine applications, demand drivers and relevant revisions of industry standards, and found out that zinc consumed in shipbuilding is not merely a matter of raw material usage, but closely tied to factors like hull anti-corrosion solutions, vessel structural design and ship delivery schedules.

1.       Where is zinc used in ships?

Zinc is mainly deployed in three scenarios within the shipbuilding industry. First, zinc alloy sacrificial anodes are adopted for the cathodic protection of ship hulls. Second, zinc-rich primers, shop primers and similar products serve as anti-corrosion purposes for steel plates and compartments onboard vessels. Third, hot-dip galvanizing is applied locally to fasteners, fittings and other components for surface corrosion protection, of which the first part has the closest linkage to ships, and its demand for zinc is also the largest.

2.       Categories of zinc sacrificial anodes

2.1 GB/T 4950-2021 “Zinc Alloy Sacrificial Anode”

GB/T 4950-2021 is the current applicable product standard for zinc alloy sacrificial anodes, which was issued on August 20, 2021 and implemented on March 1, 2022. It supersedes GB/T 4950-2002 and GB/T 4951-2007. The standard specifies the classification, types, specifications, technical requirements, test methods and inspection rules for zinc alloy sacrificial anodes. Its core is to regulate the performance indicators of anode products, rather than the quantity of anodes configured for individual vessels.

2.2 GB/T 4948-2025 “Aluminum Alloy Sacrificial Anode”

GB/T 4948-2002 is a long-standing classic standard serving the field of cathodic protection for ships and marine engineering, which was issued on August 29, 2002 and implemented on January 1, 2003. It should be noted that this standard was officially superseded by GB/T 4948-2025 “Aluminum Alloy Sacrificial Anodes” on August 1, 2025.

3.       Forecast of zinc usage in shipping industry

Zinc consumption in the shipping industry cannot be simply estimated as "number of vessels multiplied by quantity of anodes per vessel". A more rational calculation chain is as follows: the wetted surface area (WSA) is derived from deadweight tonnage or displacement, and the actual consumption of zinc anodes is subsequently calculated by combining the anode consumption rate, utilization factor and safety factor.

4.       Boost to zinc consumption by the “delivery wave” during the high prosperity cycle of the shipbuilding industry

The shipbuilding industry is a typical large-cycle sector. Currently, China’s shipbuilding industry is in a high-prosperity phase marked by the dual overlay of “surging newbuild output” and the “green shipping vessel replacement wave”. The stimulus to zinc consumption is generated via two channels: accelerated delivery schedules and higher zinc loading per vessel. In terms of zinc consumption structure, sacrificial anodes are not the sole beneficiaries in this cycle, while zinc-rich primers and shop primers will also benefit concurrently from the concentrated shipbuilding boom.

According to data released by the China Association of the National Shipbuilding Industry (CANSI), China’s ship completions reached 53.69 million deadweight tons (DWT), new orders stood at 107.82 million DWT, and the orderbook amounted to 274.42 million DWT throughout 2025.

Table 1 Prosperity indices of China’s shipbuilding industry

Based on our rough estimates (excluding replacements or dry-docking maintenance of existing vessels and zinc-rich coatings), zinc consumption for sacrificial anodes fitted on China’s new ship completions is approximately 5,500–9,800 during 2022-2025. If replacements or dry-docking maintenance for in-service vessels are included, the actual consumption will be significantly higher than the estimated figure.

Chart 1 The amount of zinc used for sacrificial anodes in new ships

From the perspective of industrial cycles, the ship industry will embrace a concentrated deliveries of ships following the elevated orderbook. Over the next two to three years, as high-value-added vessels are completed in batches, procurement for anode installation and zinc-rich coating applications in the mid-to-late construction phase of newbuilds is expected to expand concurrently, which will make shipbuilding a more elastic source of marginal growth in zinc demand.

(If you have any queries about the news, please contact Shelley via Email: xiexuhang@antaike.com, or phone: +86-10-63978092, ext. 8223)