圆坯连铸机电磁搅拌磁场特性研究

Research on magnetic field characteristic of electromagnetic stirrer for round caster

采用CST-11A型数字特斯拉计、扭矩仪测量对某圆坯连铸机结晶器与末端电磁搅拌的磁场、电磁扭矩进行测试研究,研究了磁感应强度和扭矩与电流、频率的变化规律及磁场的空间分布特点。研究表明:电磁力与磁感应强度的平方成正比关系,频率和磁感应强度成反比关系。结晶器内磁感应强度轴向最大位置在距结晶器上口900 mm位置,向两侧陡降;径向分布不均匀,由搅拌器内表面向中心逐渐减小;高频率的磁场经结晶器铜管后衰减更大。结晶器、末端电磁搅拌的电磁扭矩随着电流强度和频率的增加而增大,频率对结晶器电磁扭矩影响较电流影响更为平缓,而末端电磁扭矩与频率的变化趋势受频率范围影响,研究结果对合理制定及优化电磁搅拌工艺参数提供了理论依据。

The magnetic field and twisting moment of mold electromagnetic stirrer（M-EMS）、final electromagnetic stirrer（F-EMS） for round billet were measured by CST-11 A Digital Tesla meter and Torque Meter. The magnetic field distribution of direction in the mold was summarized. The relations of magnetic field and twisting moment with current and frequency were analyzed. The results showed that the electromagnetic force is proportional to the square of magnetic flux density, the frequency is inversely related to magnetic flux density; maximum magnetic flux density along axis of mold appears at 900 mm away from the upper, and then fall dramatically in both sides; distribution of magnetic flux density unevenly distributes along radius of mold,gradually decreases from the inner surface to the center; high frequency passed through mold attenuates more. Twisting moment of both M-EMS and F-EMS increases with current and frequency; twisting moment of M-EMS increases with frequency more slowly than current; the relation between twisting moment of F-EMS and frequency is affected by the range of frequency.The resultes provided the theoretical basis for formulating and optimizing the reasonable technological parameters.