SUPPLEMENTARY TOOLS TO MEASURE AND UNDERSTAND THE FLOW IN THE CONTINUOUS CASTING MOULD

For the production of clean steel it is important to control the flow in the mould. A lot of modelling workhas already been done to study the flow behaviour in the mould. Measurements in the continuous castingmould are necessary to validate the modelling work, especially when multiphase flow is studied or whenelectromagnetic flow control systems are incorporated. For a few years, two measuring principles have beenused to study the flow behaviour at the meniscus in the mould at Corus IJmuiden No.2 BOS. The mainmethod is a simple flow measuring device, which consists of a refractory tube sealed at the bottom and fixedat a pivoting point at the top. The tube is submerged in the liquid steel in the mould. Measuring the resultinginclination angle reveals the flow direction and gives a measure of the velocity. In this way the effect of castingparameters on flow behaviour can be studied, such as the effect of the submersion depth of the SEN, the Arflowon the shrouding system (between the tundish and mould) and the change from double roll to single rollflow in the mould. Also, measurements are done with the ‘nail board’ method giving a snapshot of the flowdirection at multiple locations in the meniscus. An electromagnetic sensor was used to measure the multiphaseflow condition in the SEN. In this paper results of these measurements are shown and examples are comparedwith CFD calculations. A better understanding of the effect of casting parameters on the flow pattern in themould was obtained using these supplementary tools