Development of electromagnetic stirring system at modernization ofhorizontal continuous caster

Abstract

Horizontal state of mold at continuous casting of steel in horizontal continuous casters (HCC) complicates the melt supply conditions and forming of billets, results in disturbing ofcasting process stability, in forming of zones of chemical and physical inhomogeneity, distortion of the billet geometric form, arising of longitudinal fractures, bleeding at the mold exit. A possibility to increase the quality of the billets, produced at HCCs relates to changing of conditions of the metal solidification, creation of forced melt movement, in particular, by application of electromagnetic field. To increase the casting stability andimprove quality of the billets from alloyed steels a modernization of a HCC accomplished. Within the modernization a system of electromagnetic stirring (EMS) for modernizedmold of the HCC was developed. The modernized mold for horizontal casting is equipped by a build-in two-phased stator of alternative current. The two phased EMS stator built-in into the mold shell, supplied by power from two-phased frequency convertor, developed and manufactured by “Electroprivod i silivaya electronica” LLC (Moscow). A water immersion winding is the main element of the EMS stator. The winding isolation resistance at the first stage of the water immersion stator running was more than 500 m ohm. The technology of the winding manufacturing provides a high coefficient of heat exchange between the copper wires and technical water, usedfor direct cooling. By this, high values of the winding magnetizing force is reached at a small volume that in its turn provides a wide range of stirring intensity control. The developed EMS system enables to decrease considerably the existing drawbacks of HCC.