METHOD OF PRODUCTION OF THE WIDE HOT-ROLLED STRIPS MADE OUT OF THE HIGH-CARBON STEEL GRADES Russian patent published in 2006 - IPC C21D8/02 C21D9/46 

FIELD: ferrous metallurgy; methods of production of the wide hot-rolled strips.

SUBSTANCE: the invention is pertaining to the field of ferrous metallurgy, in particular, to production of the wide hot-rolled strips made out of the high-carbon steel grades with the depth no more than 5.5 mm. The technical result of the invention is assurance in the high grades carbon steel hot-rolled rolling of the isotropic evenly distributed structure of pearlite with dispersivity of no more than 4-th grade by the strict regulation of the temperature conditions of the final part of the rolling and reeling of the hot strips into the rolls depending on their final depth. The technical result is reached due to the fact, that in the known method of production of the wide hot-rolled strips made out of the high-carbon steel grades, predominantly with the carbon content of 0.62-0.75 % and the strips depth of no more than 5.5 mm, including a slab heating for the hot rolling, rolling in the rough and final continuous trains with the temperature of the end of the rolling of 700-800°C, cooling the strips by water from above and from below with the help of the sections of the shower device mounted on the collecting roller table with the subsequent reeling in a roll at the temperature of 500-600°C. According to the invention, the temperature of the end of the rolling and reeling is set depending on the final depth of the strips. At that, the temperature of the end of the rolling and the reeling is set: - for the strips depth of 5.5-4.5 mm inclusively - of no more than 750°C; - for the strips depth of less than 4.5-3.5 mm inclusively - of no more than 770°C; - for the strips depth of less than 3.5-3.0 mm inclusively - of no more than 780°C and - for the strips depth of less than 3.0 mm - of no more than 800°C. At that the temperature of the reeling depending on the strips final depth set: - for the strips depth of 5.5-4.5 mm inclusively - of no more than 560°C; - for the strips depth less than 4.5-3.5 mms inclusively - of no more than 580°C; - for the strips depth of less than 3.5 mm - of no more than 600°C.

EFFECT: the invention ensures achievement in the high grades carbon steel hot-rolled rolling of the isotropic evenly distributed structure of pearlite with dispersivity of no more than 4-th grade by the strict regulation of the temperature conditions of the final part of the rolling and reeling of the hot strips into the rolls depending on their final depth.

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