Development of Controlled Rolling and Controlled Cooling Technology in China
my country is rich in niobium, vanadium, titanium and rare earth resources, and has broad prospects for the development of microalloy controlled rolling and controlled cooling technologies. In the past ten years, especially since the Sixth Five-Year Plan period, controlled rolling and controlled cooling technology has made considerable progress in my country. At present, the annual production of controlled rolling and controlled cooling has just exceeded 1 million tons, involving more than 20 types of steel, and has been applied to shipbuilding, oil and natural gas pipelines, boilers and pressure vessels, steel sheet piles, automobiles, and threads. Steel bars, wire ropes, bearings and geological pipes, etc. Among them, plates account for about 40%, rods and wires account for about 60%, and pipes and profiles account for a small proportion. The current application of controlled rolling and controlled cooling technology in industrial test and production is shown in Table 1-1. The effects obtained by the controlled rolling and controlled cooling process in the domestic mills in the comprehensive performance of the outline products are listed in Table 2.1 and 2.2.
Shanghai Steel's 2350mm two-high-four-high medium plate rolling mill and Wuhan Iron and Steel's 2800mm two-high-four-high medium plate rolling mill adopt a two-stage controlled rolling process to produce 09MnNb and 16MnNb steel DH360N grade ship plates that meet the requirements of Lloyd's ship regulations; The 2300mm three-high-four-high medium plate rolling mill of the No. 3 plant adopts a hybrid controlled rolling process combined with post-rolling controlled cooling to produce container steel plates whose performance reaches the physical water products of similar foreign products. The 1700mm hot tandem mill of Wuhan Iron and Steel Hot Rolling Plant adopts Type I and Type II controlled rolling processes, or combined with controlled cooling after rolling, to develop X60 and X65 grades of niobium-containing microalloy steel coils with a thickness of 7~12mm that meet the requirements of API-5L standards . The medium plate rolling mill of Taigang No. 5 Rolling Plant adopts the controlled rolling process, which solves the problems of low aging impact value of 20g steel and low yield strength of 16Mng steel, and improves the qualified rate of hot rolling performance by more than 15%; Wuhan Iron and Steel Rolling Plant adopts the controlled rolling process , The qualified rate of hot rolling performance of 4C ship plate has been improved by more than 38%. The 2300mm three-roll Lauter-type medium plate rolling mill in Handan Iron and Steel Plant adopts IB-type controlled rolling process. After rolling, water curtain cooling improves the comprehensive performance of A2F and 20g medium plate. Pass rate.