Extra large diameter seamless steel pipe plant opens in Hunan

The world's first and largest diameter seamless steel pipe continuous rolling production line went into operation on Monday in Hengyang, Hunan province, marking a historic leap in China's independent manufacturing capacity for extra large diameter premium seamless steel pipes.

With a total investment of 3.07 billion yuan ($453.75 million), the production line is designed to produce 800,000 metric tons of seamless steel pipes annually.

Its products cover outer diameters ranging from 323.8 millimeters to 630 mm, with wall thickness between 7.2 mm and 65 mm.

According to Liu Jilin, deputy general manager of Hengyang Valin Steel Tube Co Ltd (HYST), the facility comprehensively serves high-end applications including large-diameter oil casing, oil and gas transmission pipelines, pressure vessel pipes, submarine pipelines, new energy equipment tubes and high-end machining tubes.

"We've overcome multiple industry-wide rolling technical challenges and mastered core processes for extreme thin-wall rolling," he said.

Equipped with an artificial intelligence-powered industrial internet control platform, the production line integrates three core systems — automated intelligent three-dimensional warehousing, an intelligent plant control center and full-process intelligent inspection equipment — enabling "one-click fully automatic pipe rolling" intelligent production.

According to Liu, the dimensional accuracy, product performance and quality stability have reached industry-leading levels.

Liu said the project was completed efficiently in just 18 months, setting a new speed record for similar production line construction.

"Upon reaching full capacity, the line is expected to generate an additional 5 billion yuan in annual sales revenue, and create over 1,000 jobs," he said.

Leveraging the full-process intelligent production line, the company will expand into high-end tube markets both at home and abroad, promoting high-quality development of the specialty steel pipe industry through digital and intelligent upgrading, he added.

Sources from Hunan Iron and Steel Group, parent company of HYST, said the project will consolidate HYST's position as the world's largest single-site seamless steel pipe production base, and help elevate China's seamless steel pipe sector into the global high-end large diameter arena.

As a core supporting project of Hunan's advanced steel materials industrial cluster, the production line is expected to further strengthen the "steel triangle" industrial layout in central and southern Hunan, extend the province's specialty steel pipe industry chain, drive the agglomeration of upstream and downstream supporting industries, and support Hunan in building itself into a national-level advanced materials industry hub.

Zhu Youfang contributed to this story.