Recently, Shanxi Jianbang Group's 1.8 million tons per year dual high-speed bar expansion project, contracted by Sinosteel Equipment & Engineering Co., Ltd. (Sinosteel MECC) on EPC basis, has successfully started production. This marks the first production line in China to use the RVM330 module rolling mill for dual high-speed bar and composite plain bar, bringing a successful conclusion to the collaboration between the two parties.

China's First Dual High-speed Bar and Composite Plain Bar Production Line

In January 2022, the 1 million tons per year high-speed bar project in Shanxi Jianbang, EPC contracted by Sinosteel MECC, broke the previous highest record for key technology in a fully continuous high-speed bar rolling system by achieving a stable rolling speed of 42.75 m/s.

Building on the success of this collaboration, the two parties joined forces again, with Sinosteel MECC responsible for transforming the existing ordinary bar production line into a three-channel high-speed bar production line, capable of producing 1.8 million tons per year. The product specifications include Φ12-25mm (high-speed bar on the fast finishing block) and Φ28-40mm (bar on the intermediate finishing block), with the ability to reserve production capacity for Φ50mm premium round steel.

This marks the first dual high-speed bar and composite plain bar production line in China to use the RVM330 module rolling mill, achieving full coverage of specifications from Φ12mm to Φ40mm. This design allows for cost reduction, increased production, and efficiency through dual cutting and rolling for high-speed finishing block production while retaining the ability to produce large-diameter threaded steel on the intermediate finishing block.

Independent Advanced Technology, Cost Reduction, and Efficiency Improvement 

/ Upgraded and Optimized Full-line Production Process 

Sinosteel MECC is responsible for optimizing and adjusting the entire production process and upgrading relevant equipment. The traditional arch rolling mill was replaced with a short stress line rolling mill, and 2 sets of independently developed RVM330 module rolling mills were added to achieve hot rolling processing. The production line also includes a three-roll reducing and sizing mill to ensure the ability to produce high-quality bar products.

The project team of Sinosteel MECC used its independently developed long product rolling system technology and equipment to achieve flexible control of cooling and low-temperature rolling for large specifications, with a maximum low-temperature rolling specification of up to 36mm. The production line can meet the low-cost production of 500MPa threaded steel, with fine grain size, excellent metallographic structure, an obvious yield platform in the tensile curve, and stable product performance. The post-expansion dual high-speed bar production line has achieved upgrades and optimizations, cost reduction, and efficiency improvement, with fewer personnel involved.

RVM330 Module Rolling Mill + 45m/s Rolling
Large specifications, high-speed crop and cutting, high-speed bar on the fast finishing block system, and double-tail braking effectively ensure a maximum rolling speed of 45m/s. The use of the 330mm module rolling mill addresses the demand for low-temperature rolling of large specifications.

Significant Reduction in Alloy Content + Lowest Mn Content Nationwide
The overall process design considers low-cost production of 500MPa threaded steel while significantly reducing alloy content:
Below Φ28mm specifications, vanadium (V) and niobium (Nb) alloys are not added.
For Φ12mm specifications, manganese (Mn) content is below 0.8%.
For Φ25mm specifications, Mn content is below 1.2%, making it the lowest nationwide.

Stable and Precise Rolling + Increased Yield
The production line achieves precision negative tolerance rolling. The already commissioned single high-speed bar can control negative tolerance within 5.1%, with a yield of 103.5%, significantly reducing costs and achieving a rolling cost reduction of -20 yuan/ton, ranking among the top in the country.

Increased Direct Rolling Rate + Energy Saving
The project adopts the continuous casting billet direct rolling technology, achieving a direct rolling rate of 80%. This reduces secondary heating steps, saves energy consumption, lowers metal losses, and reduces production costs, greatly reducing carbon emissions.

Automation, Efficiency, and Fewer Personnel
The rolling line adopts a one-line, one-room control approach, concentrating all operations for greatly improved efficiency, making the production process highly automated, efficient, and requiring fewer personnel. Currently, the Jianbang dual high-speed bar production line has only 22 personnel per shift, with a total staffing of 141 for the entire dual high-speed bar production line.

The successful commissioning and record-setting innovation of the Shanxi Jianbang 1.8 million tons per year dual high-speed bar expansion project is another successful application of Sinosteel MECC's independent and efficient long product rolling system technology. This success is attributed to Sinosteel International's persistent commitment to "technology as the primary productivity" and dedication to innovation. It reflects the continuous efforts of Sinosteel MECC's vast team of technology workers who shoulder the responsibility of "showcasing the green foundation of steel." They unite, strive forward, focus on tackling challenges, play a strategic role, and contribute wisdom and strength to the high-quality development of customers and the industry.