Every transformer core starts long before it reaches a factory floor. It starts at a steel mill, as a slab of electrical steel that still has to be hot-rolled, cold-rolled, annealed, and coated before it can be called grain-oriented silicon steel (GOES) — the material every transformer core is built from.
Buyers rarely ask where that steel comes from. But the mill matters: grade, thickness, and coating quality set the ceiling on a transformer’s core loss and no-load current before a single lamination is ever cut. Here’s who actually makes that steel in China, and what each producer is set up to supply.
China’s Grain-Oriented Silicon Steel Producers
As of the end of 2025, China’s total effective capacity for transformer-grade grain-oriented silicon steel (CRGO) stood at roughly 4.08 million tons, with 2025 output around 3.45 million tons and industry-wide utilization near 84.5%. High-permeability Hi-B grades made up about 77% of that output — a sign the industry keeps shifting toward higher-grade product. Add in non-oriented electrical steel and China’s combined electrical steel capacity runs to roughly 24.35 million tons a year. Below are the nine producers most relevant to transformer manufacturing.
China Baowu Steel Group Corporation Limited is the clear leader, with roughly 1.2 million tons of effective GOES capacity today and a planned expansion to about 1.64 million tons. Its Wugang base in Hubei runs the country’s largest high-end oriented line — Hi-B, ultra-thin 0.18/0.20/0.23mm gauges, laser-scribed grades — feeding core UHV transformer projects, while its Baoshan base in Shanghai covers conventional CGO plus the full Hi-B range. Baowu supplies State Grid and China Southern Power Grid’s UHV programs and major domestic transformer makers, and exports to roughly 38 countries and regions across South and Southeast Asia, the Middle East, Brazil, Europe, and North America.
Shougang Group Co., Ltd. was one of the first Chinese mills to master a full low-temperature Hi-B process, and its ultra-thin 0.18–0.23mm oriented steel capacity — about 380,000 tons across its Qian’an (Hebei) and Changzhou (Jiangsu) bases — leads the domestic field. Shougang supplies North and Northwest China’s transformer makers, including TBEA and Baoding Tianwei, and exports Hi-B grades to Turkey, the Middle East, the EU, Southeast Asia, and India, largely for wind-power step-up transformers and premium distribution units.
Angang Steel Group (Ansteel) runs the only fully integrated GOES mill in Northeast China, with 100,000 tons of effective capacity at its Bayuquan base in Yingkou, Liaoning. It produces both conventional CGO and Hi-B grades aimed mainly at the northern grid and regional distribution transformer manufacturers, with modest export volume into Russia, Mongolia, and Central Asia.
Shanxi Taigang Stainless Steel Co., Ltd. is one of a handful of Chinese mills with full in-house mastery of high-permeability oriented steel manufacturing. Its Taiyuan base, with 160,000 tons of capacity, is a steady mid-to-high-grade supply source for transformer makers across North and Northwest China, building on Baowu’s technology base to keep iterating toward higher grades.
Hunan Valin Lianyuan Iron & Steel Co., Ltd. operates Central China’s state-owned, fully integrated silicon steel base in Loudi, Hunan. Its existing 100,000-ton oriented line, capable of stable Hi-B output for mid-to-large power transformers, is running near full capacity, and a second phase targeting 200,000 tons is slated for 2027. Valin Lianyuan serves Central and South China, supplying manufacturers like XD Group and Ginlong, and is expanding into Southeast Asia and Latin America alongside China’s transformer export supply chain.
Anyang Iron & Steel Co., Ltd. brought Henan’s first fully integrated high-permeability oriented line online in 2025, with 60,000 tons of new capacity. It closes a gap in the province’s high-end silicon steel supply and mainly serves the Central Plains and North China transformer manufacturing cluster, while the company also develops export channels into Brazil and other Latin American markets and pursues North American certification.
Chongqing Wangbian Electric (Group) Co., Ltd. is Southwest China’s leading private-sector oriented steel processor, and one of the few companies in the industry that combines silicon steel processing with its own transformer manufacturing under one roof. Of its 180,000 tons of capacity, roughly 130,000 tons is Hi-B grade, split between internal consumption and external sales. Its transformer arm absorbs a meaningful share of that output directly, while the rest ships domestically to Southwest and Central China and exports to smaller transformer makers in Southeast and South Asia.
Baotou Weifeng New Material Co., Ltd. runs a large private, semi-integrated processing operation in Inner Mongolia with 150,000 tons of capacity and a self-developed continuous tunnel-type annealing furnace, giving it a technical edge in ultra-thin oriented steel. It covers the North and Northwest China transformer cluster and exports to Central Asia, Russia, and Southeast Asia, mainly supplying cost-competitive material for distribution transformers.
Henan Angang Longdu Electromagnetic New Materials Technology Co., Ltd. is a newer joint venture between Anyang Iron & Steel, Baotou Weifeng, and a local state investment platform, built specifically to produce high-end Hi-B oriented steel, with 80,000 tons of Phase 1 capacity at its Zhoukou, Henan base and a stable hot-rolled feedstock supply from Zhoukou Iron & Steel. It targets small and mid-sized transformer manufacturers across Central China, North China, and East China, including the equipment cluster around Xuji Group in Henan.
(Capacity figures reflect publicly reported industry data and can shift with ramp-up schedules and reporting periods. They’re provided for industry reference and business context only, not as certified production figures. The nine companies are listed in the order presented above for reference only — the sequence does not reflect company scale, technical strength, or industry ranking.)
A Concentrated, Fast-Moving Field
Put side by side, these nine producers span a wide range of scale and specialization. Baowu’s roughly 1.2 million tons of effective capacity is by far the largest single figure among them, covering everything from conventional CGO to the thinnest Hi-B grades used in UHV transformers. Shougang (380,000 tons), Wangbian (180,000 tons), Baotou Weifeng (150,000 tons), and Angang Longdu (80,000 tons, Phase 1) each pair sizable capacity with a specific specialty — ultra-thin gauges, integrated in-house transformer production, or a fast-ramping new joint venture. Taigang (160,000 tons), Valin Lianyuan (100,000 tons, with a further 200,000 tons planned for Phase 2), Angang (100,000 tons), and Anyang (60,000 tons) round out the group with smaller, regionally-anchored bases that keep North, Central, and Northeast China supplied.
The pattern worth watching is where new capacity is landing. Anyang’s line only started production in 2025, and Angang Longdu is a first-phase joint venture still ramping up — both signs that mid-sized Chinese steelmakers are moving into a market long dominated by the state-owned giants, while Valin Lianyuan’s planned second phase suggests the established players aren’t standing still either. For anyone tracking China’s transformer supply chain, these nine mills are the ones setting the pace on grade, capacity, and where the country’s electrical steel actually gets exported next — and on the quality of the steel that eventually ends up inside dry-type and oil-immersed transformer cores. For a closer look at what happens to that steel once it reaches a factory floor, see our guide to how we build every transformer core.
