Multi-zone electromagnetic stirring device and method for continuous casting machine crystallizer

Abstract

The invention discloses a multi-zone electromagnetic stirring device and a multi-zone electromagnetic stirring method for a continuous casting machine crystallizer, and belongs to the technical field of continuous casting equipment and the continuous casting method, and the device and the method are used for improving the electromagnetic stirring effect of the whole crystallizer area. According to the technical scheme, the invention adopts a combined structure of an upper electromagnetic stirring coil and a lower electromagnetic stirring coil, and a stirring method, so that the stirring effect of molten steel at the meniscus of the crystallizer is guaranteed, and the stirring zone of the molten steel is prolonged. The upper electromagnetic stirring coil can be started for steel types with high surface quality requirements, the lower electromagnetic stirring coil can be started for steel types with strict subcutaneous and segregation requirements, and the two groups of electromagnetic stirring coils are simultaneously started to work for the steel types with casting blank surface quality requirements and internal quality requirements. The structure of the conventional electromagnetic stirring device and the stirring method are broken through, the electromagnetic stirring metallurgical requirements of different zones of the crystallizer can be improved in a targeted mode, requirements of different steel types on equipment performances can be met, the quality of the casting blank can be effectively improved, and the economic benefits are remarkable.

Description

technical field [0001] The invention relates to an electromagnetic stirring device and method suitable for a crystallizer of a special steel bloom continuous casting machine, and belongs to the technical field of continuous casting equipment and methods. Background technique [0002] During the continuous casting process, the molten steel on the wall of the mold first crystallizes and solidifies. Due to the uneven flow field and heat transfer of the molten steel in the mold, the shell of the slab grows unevenly, and surface defects and subcutaneous slag are prone to occur. Electromagnetic stirring of the mold is an effective measure to improve the surface quality, subcutaneous slag inclusion and internal quality of the slab. The induced magnetic force generated by the electromagnetic stirring of the mold promotes the rotational movement of the molten steel core in the mold, which can evenly distribute the temperature in the mold and eliminate the influence of superheat; the ...

AI Technical Summary

Problems solved by technology

However, the traditional electromagnetic stirring of the mold of the continuous casting machine only stirs the middle and lower parts of the mold and the area of ​​the foot roll. The stirring area is lagging behind, and the meniscus of the mold has basically no induction magnetic force, which cannot effectively solve the uniform growth of the primary shell question

In order to solve the problem of uniform growth of the primary slab shell, some continuous casting machines adopt stirring at the upper end of the crystallizer. Although this method can greatly improve the uniformity of the primary slab shell of the cast slab, the length of the stirring coil is about 300-400mm, the length of the mold copper tube is 700-1000mm, the stirring area is small, there is no magnetic induction in the middle and lower part of the mold and the foot roll area, and the strong cooling process in the middle and lower part of the mold and the foot roll area still causes the billet shell to quickly The uneven growth of the slab leads to uneven subcutaneous and internal structures of the slab, and the segregation of the slab is relatively large

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