METHOD FOR PRODUCTION OF HOT-ROLLED PLATE WITH HIGH COLD RESISTANCE FOR PRODUCTION OF ELECTRIC-WELDED PIPES AND WELDED STRUCTURES Russian patent published in 2020 - IPC B21B1/22 C21D8/02 

FIELD: physics.

SUBSTANCE: invention relates to the field of production of flat rolled products, mainly with thickness of up to 40 mm, with high cold resistance for production of electric-welded pipes and welded structures at reversible plate mill. Proposed method comprises billet heating above temperature of Ac₃, fractional deformation and cooling in controlled accelerated cooling unit. Prior to deformation blank is heated to temperature not less than 20 °C and not more than 70 °C above temperature of niobium carbonitrides in steel dissolution, with total heating time of not less than 0.9 min per 1 mm of thickness of blank and duration of exposure t = 1 ÷ 2.2 h. Preliminary stage of rolling is performed with minimum degree of deformation per pass ε_i, arranged with mathematical expression.

EFFECT: invention enables to obtain articles with high and stable values of impact viscosity and a portion of the viscous component in the fracture of samples at low temperatures.

3 cl, 1 dwg, 9 tbl