Electromagnetic Stirrer for Continuous Casting Machine (EMS for CCM)
The thing which removes the major defect into metal billets.
Electromagnetic stirrer are used to stirrer fluid. EMS give real change in steel sector melting area. Electromagnetic stirring (EMS) is one of methods to improve the quality of continuously casted billet.
Under EMS impact nonmetallic inclusions are removed out of the solidification area and move to the center of the meniscus of liquid metal. Besides, high speeds of convection flows in the liquid metal avoid the remaining gases at the crystallization border and decrease therefore the number of gas bubbles under the metal shell.
This mechanism of EMS action in a mold results in a decrease of gas bubbles under the metal shell and impurities in continuously casted billet. Operation of a billet CCM was studied at Moldavsky steel-works, where an EMS stator was embedded into the mold. Influence of EMS on the quality of continuously casted billet was studied.
The influence of EMS in the mold on the billet macro structure was revealed, compared with a standard strand. The following phenomena were studied: decrease of average degree of cracks and liquation strips along the billet section, of cracks in the billet axis zone, central pore volume and border point contaminations; increase of axis liquation degree (but liquation became more distributed), decrease of carbon axis liquation coefficient in high carbon steels.
The average growth values of equiaxed crystal zone at the templates of test heats with EMS amounted for 55% at high carbon steels comparing with regular billet templates, at the middle carbon steels — 48%, at the low carbon steels — 92%. The elaborated EMS system in the mold allows improving considerably the quality of continuously casted billets.
NEEDS
Quality enhancement
Production Rate increase
New steel grade production
Production rejection reduction
ADVANTAGES
Surface and sub-surface quality enhancement
Solidification structure improvement
Central soundness enhancement
Stirrer custom design on new and existing CCM
Energy saving design
