METHOD OF PRODUCTION OF ROLLED SHEETS Russian patent published in 2006 - IPC C21D8/02 B21B1/46 

FIELD: metallurgy; production of rolled sheets for manufacture of electrically welded straight-seam tubes of larger diameter.

SUBSTANCE: proposed method includes melting of steel, alloying, ladle treatment, teeming steel into ingots or continuously cast blanks; as a result, steel of definite composition is obtained at ratio of [Manganese] x [Niobium] = (2.5-3.5) 10^-2. After teeming, ingots are rolled into slabs and are cooled down; continuously cast blanks are cooled down and are subjected to preliminary and final deformation to required sizes of rolled sheets (final deformation is completed in preset temperature range). Heat treatment of rolled sheets is proposed as version. Heat treatment is performed at definite mode and is followed by cooling to surrounding temperature.

EFFECT: enhanced efficiency; enhanced strength characteristics and cold resistance of metal; enhanced corrosion resistance.

3 cl, 1 ex