鋼模液面渦電流量測系統發展

The Development of Eddy Current Detection System Steel for Mold Level in a Steel Mill

陳重楣(C.M. Chen) ； 高振隆(C.L. Kao) ； 林宏達(H.T. Lin)

《鑛冶：中國鑛冶工程學會會刊》 50卷4期 (2006/12) Pp. 173-177

https://doi.org/10.30069/MM.200612_50(4).0013

摘要

因渦電流方法精確度比γ射線法高，在連續澆鑄控制上普受歡迎。首先理論分析差異型感測線圈電磁場及感應電壓，建立訊號特徵及規範。然後依此發展電路。電路功能包含高功率正弦波產生器、差異訊號放大、帶通濾波、均方根值計算、位準電壓設定、模振訊號濾除、對數放大。校正試片用電磁特性與鋼液相近之304不銹鋼片。由校正數據及澆鑄前兩個量測範圍確認值，電腦計算出液面高度並傳給閥門控制器。自啓鑄至澆鑄結束，液面浮動可控制在±3mm以內。

關鍵字

鋼 ； 連鑄 ； 模液面 ； 量測 ； 渦電流

並列摘要

The eddy-current type mold level detector, other than γ-ray, is becoming popular in steel continuous casting, due to its higher accuracy. Firstly, the theoretical electromagnetic fields and force s of a differential-coils sensor were analyzed to establish a distance measurement scheme. Then, an electronic circuit was built, accordingly. The functions of the electronic circuit included sinusoidal current generation, differential amplification, band-pass filtering, root-mean-square measurement, offset adjustment, mold oscillation signal ejection and logarithm amplification. The calibration specimen used was a piece of 304 stainless steel plate whose electromagnetic properties are very similar to those of molten steel. With the calibration data and two range-checking values taken just prior to each casting, a computer calculated the mold levels from the measuring values and transmitted them to the valve controller. It worked effectively through the entire casting sequence. The level turbulence could be reduced within the acceptable range of ±3mm, which is not obtainable by γ-ray method.

並列關鍵字

Steel ； Continuous casting ； Mold level ； Measurement ； Eddy current