In the continuous casting (CC) process, it is technically of great importance to measure accurately the level of molten steel in the mold and to keep the level constant, because this results in the more stable casting operation and the improved casting quality.
The development has been made on an eddy-current CC mold level meter based on the method of a positive feedback amplification. This new non-contact level meter is capable of measuring the molten steel level without the influence of the mold powder. An accuracy of the level meter is ±1mm under a quick response. Moreover, aΔdifferential type of the detecting coil has been developed from a theoretical analysis of the electro-magnetic field of the level meter. This type of the level meter is more stable against an influence of the environmental condition, such as a position of the mold wall. By using the differential type, a small sized level detector of which diameter of 30 mm is realized and it can be applied to a billet casting with a smaller cross-section.
The eddy-current type mold level meter is in use not only at NKK's Keihin and FukuyamaΔWorks, but also abroad, to improve the CC technology.
