EFFECT OF NONSTEADY CONTINUOUS-STEEL-CASTING REGIMES ON THE QUALITY OF SEMIFINISHED PRODUCTS AND FLAT-ROLLED PRODUCTS

摘要

Given the continually tightening requirements on the quality of steel and the saturation of the market with metal products, one of the main problems facing steelmakers is reducing production costs by significantly improving the quality of the continuous-cast semifinished product. Researchers and engineers have recently turned their attention to nonsteady (transient) processes in the continuous casting of steel [1-3]. All of the transient processes in the casting operation can be divided into standard and nonstandard transients. Among the former are the processes stipulated by the specifications, such as starting up the caster, ending the casting operation, and replacing the submersible nozzles and tundishes to cast slabs of certain lengths. Among the latter are processes connected with emergencies or other unforeseen situations: destruction of the refractory channel for the steel (the stopper, metering nozzle, and submersible nozzle) or a change in its initial dimensions; failure of components of the continuous caster (the mold oscillation mechanism, the mechanisms that raise, lower, and secure the tundish, the ingot withdrawal system, etc.) [4].