METHOD OF PRODUCTION OF THIN-SHEET COLD-ROLLED STEEL Russian patent published in 2009 - IPC B21B1/28 

FIELD: metallurgy.

SUBSTANCE: method is provided for increasing of consumer properties of cold-rolled steel containing 0.07…0.14 wt % of carbon, of thickness 2.0…2.5 mm with glossy finish ensured by improvement of its surface. Method includes installation in mill stands of new rolls with specified microgeometry of its barrels, rolling, annealing and pinch-pass rolling of strips. Increasing of conditioned outcome with glossy finish is provided ensured by rolling of strip is started after receiving of 1000 t of rolling with non-glossy finish at new working rolls of the latter rolling mill stand with height of microroughnesses of its barrels Ra=4.6…5.5 micrometres, and in rolls of this mill with Ra=4.0…4.5 micrometres and Ra=3.0…3.5 micrometres after rolling, correspondingly 500 t and 350…400 t of strips with non-glossy finish, annealing of rolls after rolling is implemented in bell-type furnaces with protective hydrogenous atmosphere, with acceleration of temperature of the most decelerating by heating point of roll, with launch of water-cooling at temperature 300°C, air-cooled without ventilation and with duration of isolation under bell with switch off burners during two hours, and pinch-pass rolling of annealed strips is implemented in grooved rolls with Ra≤1 micrometres.

EFFECT: increased consumer properties of cold rolled steel.

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