Rolling mills have a development history spanning hundreds of years, with clear historical records tracking their technological iteration:
En 1480, Leonardo da Vinci from Italy drafted the first conceptual sketch of a rolling mill.
En 1766, British engineer J. Purnell upgraded a hand-operated lead sheet rolling mill and invented the two-high rolling mill for wrought iron bar production.
En 1779, j. Picard successfully applied steam engines to drive rolling mills, drastically boosting the production capacity and application scope of rolling equipment.
En 1783, British inventor H. Cort manufactured a water wheel driven two-high section rolling mill, which greatly accelerated the popularization of section steel rolling technology.
Por 1854, Europe launched the first steam-powered two-high reversible medium plate rolling mill.
En 1864, the United States put the first three-high Lauth medium plate rolling mill into operation.
En 1891, U.S. Steel built the world’s first four-high reversible medium plate rolling mill.
En 1897, German engineers replaced steam engines with electric motors for rolling mill driving systems and achieved stable industrial operation.
En 1910, Vítkovice Klement Gottwald Iron and Steel Company in Czechoslovakia commissioned a full set of 4500mm two-high heavy plate rolling mill.
En 1912, the Ilyich Metallurgical Plant in Zhdanov, Soviet Union, completed an identical 4500mm heavy plate rolling mill.
World War Wars Drove Breakthroughs of Extra-Wide Heavy Plate Mills
The massive military material demand during the two World Wars of the 20th century greatly accelerated rolling mill technology innovation. Double-stand, semi-continuous and fully continuous medium plate rolling mills were successively developed worldwide. After World War II, amid the Cold War arms race, the U.S., Soviet Union, Germany and Japan constructed dozens of 4100mm–5500mm extra-wide heavy plate rolling mills one after another.
Históricamente, the core motivation for major industrial nations to build ultra-wide heavy plate rolling mills was to produce oversized shipbuilding steel plates for aircraft carriers, battleships and other warships. Aircraft carrier flight decks must withstand intense impact force from landing fighter jets; battleships and cruisers require large-area armor steel plates. Longer and wider steel plates can cut down welding workload significantly. Driven by wartime military needs, the U.S., Soviet Union, Germany and Japan all invested heavily in large heavy plate rolling mill projects.
As early as 1918, to support aircraft carrier manufacturing, Lukens Steel Co.’s Coatesville Works in Pennsylvania, EE.UU, commissioned a 5230mm four-high heavy plate rolling mill—the world’s first rolling mill wider than 5 metros. This landmark equipment supplied high-quality single-piece heavy shipbuilding plates for mass production of U.S. aircraft carriers and battleships.
[Image: The world’s first 5230mm four-high heavy plate mill at Lukens Steel]
En 1922, Norfolk Naval Shipyard refitted a coal transport vessel with a flight deck and launched USS Langley (CV-1), America’s first aircraft carrier. Between 1922 y 1950, leveraging its dominant industrial strength, the U.S. built and refitted 46 fleet aircraft carriers plus over 100 escort carriers, laying a solid foundation for its WWII naval victory.
En 1935, Germany lifted WWI military restrictions and started construction of Bismarck-class battleships. The warships featured 8.4-meter tall side armor made of 320mm-thick KCn/A case-hardened steel produced by Krupp AG; total armor steel weight per vessel reached 17,450 montones.
To manufacture larger H-class super battleships, Krupp AG built a 5000mm four-high extra-wide heavy plate rolling mill at its Horde Steel Works in Dortmund in 1938, dedicated to naval steel plate supply.
For wartime military preparation, the Soviet Union commissioned a 5300mm four-high heavy plate rolling mill at Moscow’s Serp i Molot Metallurgical Plant in 1940. The mill mass-produced armor plates for tanks and warships and delivered critical support to the Great Patriotic War.
Antes 1940, Terni Steel Plant of Italy launched a 4600mm two-high heavy plate rolling mill.
En 1941, to expand its aggressive warfare, Japan imported massive industrial equipment from Germany: a 14,000-ton free forging hydraulic press and a steam-driven 5280mm four-high extra-wide heavy plate mill manufactured by DEMAG. The complete set was installed at Japan Steel Works Muroran Plant to speed up aircraft carrier and super battleship construction. Its one-piece cast housing weighed 230 montones, capable of rolling steel plates up to 350mm thick.
Starting in 1937 at No.3 Dry Dock of Kure Naval Arsenal, Japan built Yamato-class super battleships. The side armor adopted 410mm Vickers hardened steel processed by ten-thousand-ton hydraulic forging presses. The front armor of main gun turrets reached an extreme thickness of 650mm, with total armor steel per warship hitting 22,895 montones, contabilidad de 33% of its standard displacement.
During this period, the UK, France, Czechoslovakia, Spain and other countries also put multiple heavy plate rolling mills into operation, triggering a global boom in aircraft carrier and capital ship construction—an important prelude to the Atlantic and Pacific naval battles of World War II.
Three Global Construction Booms of Heavy Plate Rolling Mills Post-WWII
After World War II, driven by growth in machinery manufacturing, construcción naval, bridge engineering, construcción, high-pressure vessels and large-diameter oil & gas pipelines, the world witnessed three major booms in heavy plate rolling mill investment and construction.
The First Boom: United States
In the late Korean War, the U.S. reversed its post-WWII policy of halting large aircraft carrier construction. En 1952, to build Forrestal-class supercarriers, a 5335mm heavy plate rolling mill was commissioned at Gary Steel Works in Indiana.
Around the 1960s, the U.S. newly built 16 medium plate rolling mills dominated by 160-inch (4064mm) two-high + four-high double-stand configurations, incluido:
1 unit of over 5-meter extra-wide mill,
7 sets of 4064mm mills,
4 sets of 3-meter class mills,
4 sets of medium plate mills below 3 metros.
1 unit of over 5-meter extra-wide mill,
7 sets of 4064mm mills,
4 sets of 3-meter class mills,
4 sets of medium plate mills below 3 metros.
Además, 8 existing rolling mills received full modernization upgrades: 1 ultra-wide mill over 5m, 2 units of 4064mm mills, 3 units of 3m-class mills and 2 units of 2m-class mills. Multiple outdated three-high Lauth mills were phased out. Within a decade, America’s medium plate manufacturing system underwent a comprehensive upgrade with surging output.
Por 1957, U.S. medium plate annual output exceeded 10 million tons with rapidly expanding product grades: high-strength ship plate, high-toughness submarine steel, weather-resistant bridge plate and X80 steel for large-diameter longitudinal submerged arc welded (LSAW) tubería, fueling long-distance pipeline infrastructure development. Between 1961 y 1969, 8 new LSAW pipe production lines with pipe diameters ranging 406–1219mm were completed.
During this era, the U.S. commissioned 7 super aircraft carriers successively, laying a solid material foundation for its Cold War global naval deployment.
To accelerate naval modernization, the Soviet Union reassembled and commissioned a seized German 5000mm heavy plate mill at Nizhny Tagil Steel Works in 1946. En 1984, a brand-new 5000mm four-high heavy plate mill was launched at Izhorskiye Steel Plant, specially designed for aircraft carrier and large naval vessel heavy plate production.
En 1962, Dunkirk Steel Plant of France built a standalone 4320mm single-stand rolling mill. During technical revamp in 1984, a new 5000mm finishing mill was added to form a 4320mm + 5000mm double-stand mill line, which went live in 1985 to supply steel plates for Charles de Gaulle-class aircraft carriers.
En 1970, Dillingen Steel Works in Germany constructed a 4300mm finishing mill with reserved space for a roughing mill. During expansion in 1985, a DEMAG-manufactured 5500mm roughing mill was installed. Due to excessive size gap between roughing and finishing stands, the original 4300mm finishing mill was replaced with a 4800mm unit, forming a matched 5500mm roughing + 4800mm finishing double-stand rolling line, with supporting finishing lines fully modified accordingly.
The Second Boom: Japón
During the 1970s and 1980s, Japan’s rapid economic expansion triggered the second global medium plate rolling mill construction wave. Within just a few years, 17 four-high double-stand rolling mills wider than 4700mm were newly completed, incluido:
4 world-class maximum-spec 5500mm ultra-wide mills,
5 sets of 4700mm class mills,
1 set of 4200mm mill,
7 sets of 2–3m medium plate mills.
4 world-class maximum-spec 5500mm ultra-wide mills,
5 sets of 4700mm class mills,
1 set of 4200mm mill,
7 sets of 2–3m medium plate mills.
Japan’s annual medium plate output stood at merely over 2 million tons in the 1950s, jumping sharply to 20.3 million tons by 1974. Full modernization of its plate rolling industry boosted rapid growth across Japan’s machinery, construcción naval, automotor, home appliance, transportation and construction sectors.
The five 4700mm ship plate rolling mills each delivered an annual capacity of over 2 millones de toneladas, pushing Japan’s shipbuilding tonnage above 10 million tons and securing its position as the world’s No.1 shipbuilding nation.
De 1970 a 1976, skyrocketing global crude oil prices demanded 300,000–500,000 DWT supertankers and long-distance large-diameter oil & gas pipelines to cut transportation costs. Japan’s four major steel conglomerates constructed four top-tier 5500mm extra-wide heavy plate mills, deployed at Sumitomo Metal Kashima Works, Nippon Steel Oita Works, Kawasaki Steel Mizushima Works and NKK Kimitsu Works. These mills focused on wide steel plates for ultra-large oil tankers and LSAW pipe raw materials. Each single-stand mill achieved an annual capacity of over 1.5 millones de toneladas, turning Japan into a leading global steel exporter.
More than 30 years later, though these rolling mills are technically aging, continuous technical retrofits by Japanese steel enterprises maintain stable high-quality product performance and market reputation.
The Third Boom: Porcelana
Starting in 2003, the third worldwide medium plate rolling mill construction boom took root in China. By the end of October 2009, China had commissioned a total of 35 four-high single-stand and double-stand medium plate rolling mills ranging from 2800mm to 5500mm, with detailed breakdown as follows:
- 4 rolling mills above 5000mm width
- 9 rolling mills of 4100–4300mm width
- 6 rolling mills of 3800mm width
- 12 rolling mills of 3500mm width (incluido 3 single-stand Steckel mills)
- 4 rolling mills of 2800mm width
All 26 medium plate rolling mills put into operation before 2003 received varying degrees of technical renovation. Además, 7 more rolling mills over 5000mm width were under planned construction.
Prior to this nationwide expansion, China did not own a single heavy plate rolling mill wider than 4300mm.
Among China’s three existing 4m-class rolling mills back then:
- Angang Heavy Plate Mill imported a second-hand 4300mm single-stand four-high rolling mill from Sumitomo Metal Wakayama Works with multi-hundred-million RMB investment, which was commissioned in May 1993.
- Shanghai Pudong Steel’s production line adopted a second-hand 4250mm four-high roughing mill sourced from Thyssen Heavy Plate Works in Germany, matched with a domestically manufactured 3300mm four-high finishing mill from Erzhong (Deyang). The complete double-stand line started production in October 1991.
- Wuyang Iron and Steel’s 4200mm single-stand four-high rolling mill was fully domestically designed and manufactured after the Sino-Soviet split in the 1960s, led by the Ministry of Metallurgical Industry and First Ministry of Machine Building, with participation of Beijing General Research Institute of Iron and Steel, Deyang Erzhong, Dongfang Electric and other key manufacturers. This landmark domestic rolling mill was completed and commissioned in September 1978.
