MANUFACTURING METHOD OF LOW-CARBON COLD-ROLLED STEEL SHEETS Russian patent published in 2013 - IPC C21D8/04 B21B1/22 C21D9/48 

FIELD: metallurgy.

SUBSTANCE: according to the proposed method, coils of structural steel is subject to annealing with heating at the speed of 65-80°C/hour after cold rolling without any intermediate exposures to the temperature of 700°C as per a test-bench thermocouple with exposure at that temperature during the period of time of which the temperature at the point located at 1/2 of the coiling thickness of lower coil reaches 690°C and equals to 10-25 hours depending on weight of lower coil in the charge; when heating is finished, coils are subject to cooling under the heating hood during the period time, which comprises 0.25-0.6 of the exposure duration at the temperature of 700°C as per the test-bench thermocouple; then, the heating hood is removed and coils are cooled down to the temperature of 110°C in the area of charge of coils, which is delayed as to cooling process, and temper rolling is performed on working rolls with initial roughness Ra 2.0-3.5 mcm at the reduction value ε_T.R. of 0.9±0.1%.

EFFECT: improving use properties of low-carbon cold-rolled steel grade 08YuR, which meets customer requirements.

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