METHOD TO PRODUCE THIN-SHEET COLD-ROLLED STEEL Russian patent published in 2010 - IPC B21B1/28 

FIELD: process engineering.

SUBSTANCE: method comprises cold rolling, thermal treatment and temper rolling of 0.6…2.2 mm-thick steel strips containing 0.10…0.15 percent by weight of carbon and 0.05…0.17 percent of weight of silicon. Standardised-hardness products are produced by subjecting strips to annealing in single-stack furnaces with hydrogen protective atmosphere at 680° C measured by stand thermocouple and temperature at lagging point of 650°C and with dead melting at 450°…550°C for 6 hours and subsequent dead melting under single-stack with shut-off burners for 2…6 hours depending upon strip thickness. Water cooling is started at 300°…380°C depending upon strip thickness. Unsqueezing is performed at 150°…140°C at lagging point depending upon required metal surface finish. Temper rolling is performed with reduction of 0.7 to 1.5 % depending upon strip thickness.

EFFECT: production of strip steel with required strength properties.

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