Dynamic superheat determination in a continuous casting machine - process, practice and benefits

There is an increasing need to accurately control the parameters associated with casting liquid steel in a continuous casting machine. One of the main parameters is superheat, which is defined as the elevated temperature of the liquid steel above its liquidus. Liquidus is defined as being the first point of freezing. Accurate measurement of this elevated temperature is required to reliably control the casting speed of the machine. and in order to reflect the conditions in the Continuous Casting mould, which is where the liquid steel actually freezes at the start of the solid product forming process. A sensor mounted close to this and continuously monitoring the temperature is the superior solution. In order to complete the superheat picture, an accurate assessment of the liquidus must be provided in conjunction with continuous temperature. The uncertainty in the liquid steel temperature and the uncertainty in the liquidus calculation has led to a situation where liquid steel is sent to be cast with excessive superheat with a resultant over use of energy and materials. Heraeus Electro-Nite (HEN) have developed CasTemp Superheat package as a means for enhancing the visualisation of dynamic Superheat during casting, and ultimately helping to improve the control of casting through optimal use of the features included in the package. An overview and early adoption of the system is given highlighting the potential benefits for controlling superheat thereby reducing energy requirements and improving the associated process control parameters.