Production method of high-strength steel

Abstract

The invention discloses a production method of high-strength steel. After being subjected to hot rolling, coiling, bundling and online heat preservation, a plate blank is directly fed for cold rolling, and a high-strength steel cold-rolled plate is obtained through cold rolling; the finish rolling temperature of hot rolling is controlled to range from 880 DEG C to 950 DEG C, and the coiling temperature is controlled to range from 450 DEG C to 700 DEG C; bundled steel coils are directly transferred to a cold rolling unit through a steel coil transporting chain or a moving trolley, in the abovesteel coil transporting process, a heat preservation cover is adopted for carrying out online heat preservation or heating treatment on the steel coils, and hot rolling waste heat is utilized for directly completing annealing and tempering; and the internal temperature of the heat preservation cover ranges from 450 DEG C to 680 DEG C, the time of online heat preservation ranges from 1 h to 24 h, the steel coils are continuously warmed or cooled in the heat preservation cover, and after heat preservation is completed, the steel coils are cooled to room temperature in an air cooling manner and are fed to the cold rolling unit. According to the production method of the high-strength steel, the process mode of cover type furnace annealing commonly adopted in the prior art is omitted, and the production method has the advantages of being efficient and energy-saving and shortening the manufacturing period.

Description

technical field [0001] The invention relates to a hot rolling process, in particular to a production method of high-strength steel. Background technique [0002] With the development trend of market demand for high-strength steel "thinning and high strengthening", the strength level of high-strength steel has gradually increased from the previous tensile strength of 500-600MPa to 800-1200MPa, and a problem that plagues the cold and hot rolling process has emerged. Due to the high strength of the material, the rolling force of the cold rolling mill is too large, which cannot produce safely and stably. It is necessary to use hot coils to soften the material through the annealing process of the cold rolling bell furnace and reduce the rolling force of the cold rolling mill. [0003] However, this processing mode of softening hot coils by cold rolling bell furnace (such as figure 1 As shown), it will inevitably lead to an increase in the manufacturing cycle, a substantial incre...

AI Technical Summary

Problems solved by technology

Due to the high strength of the material, the rolling force of the cold rolling mill is too large, which cannot produce safely and stably. It is necessary to use hot coils to soften the material through the annealing process of the cold rolling bell furnace and reduce the rolling force of the cold rolling mill.

[0003] However, this processing mode of softening hot coils by cold rolling bell furnace (such as figure 1 As shown), it will inevitably lead to an increase in the manufacturing cycle, a substantial increase in production costs, and an increase in production energy consumption (gas consumption), which is not friendly to the surrounding environment

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