On July 28, the extra-large diameter continuous pipe rolling mill project of Hengyang Valin Steel Tube (HYST) was officially commissioned. As the world’s first continuous rolling production line for seamless steel pipes with the largest diameter, the line involved a total investment of 3.07 billion yuan and took 18 months to complete.
Designed for an annual output of 800,000 tons of seamless steel pipes, the project boasts an ultimate capacity exceeding 1.2 million tons. Its product range covers outer diameters from 323.8 mm to 630 mm, wall thicknesses from 7.2 mm to 65 mm, and fixed lengths of 6–12.5 meters.
The mill is capable of manufacturing high-pressure boiler tubes, extra-large diameter process seamless tubes for large-scale petrochemical facilities, long-distance oil & gas transmission pipelines, subsea pipeline pipes, pressure vessel tubes and oil casings. It supports the supply of large-diameter high-pressure pipelines for petrochemical projects such as large integrated refining & chemical complexes, ethylene plants and hydrogenation units, and enables domestic substitution of extra-large specification petrochemical seamless steel pipes.