Complete Electromagnetic Stirrer (EMS) System Configurationr
Electromagnetic Stirrer (EMS) is regularly used on CCM(continuous casting machine of bloom/billet), installed in the mould, strand or final. Most EMS are installed outside or inside the mould, which depends on the conditions of your casters. You can also use Mould-EMS + Final EMS together to achieve a better metallurgical effects.
An inductive Electromagnetic Stirrer is the stator of an asynchronous motor, the rotor of which is the liquid core of the continuously cast product in CCM. This stator produces either a rotating or a traveling magnetic induction field, which induces eddy current perpendicular to magnetic field. The stirrer creates mobile magnetic fields, which penetrate into the liquid steel, and creates eddy current. The magnetic induction field and the eddy current combine to create an electro-magnetic force, which causes the stirring motion in the liquid steel.
During cooling and solidification of liquid steel, columnar dendrites are formed which are oriented along the direction of temperature gradient. This causes central segregation and inter-columnar cracking when the solid shell is subjected to tensile strains during solidification. Electro magnetic stirring of liquid steel facilitates quicker dissipation of superheat and the formation of an equi-axed structure in the cast product.
Stirring of liquid pool will improve the internal structure due to better heat transfer between solidification front and liquid metal pool. The equi-axed zone in the cast product will increase whereas the central segregation will reduce. It will also help in reduction of breakouts during operation of CCM due to better dissipation of heat.
EMS consists of coil, electric controller and cooling water system. Electrica l controller consists of remote IPC, local control cabinet (PLC/IPC) and frequency inverter cabinet. |
Complete EMS System Configuration Diagram |
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