Monitoring and analysis of local mould thermal behaviour in continuous casting of round billets

Abstract A thermocouple based thermal monitoring system, employing a specially designed heat flux sensor to measure temperature and heat flux simultaneously, has been developed for the mould of a round billet caster. Based on the measured data, mould temperature and heat flux distributions are analszed for a wide range of casting conditions. The results show that the heat flux profiles along the mould length and around the mould circumference are frequently variable, especially in the area 70–110 mm below the meniscus where heat flux is much higher and more sensitive to operational parameters such as pouring temperature, casting speed, carbon content and mould powder. The local temperature and heat flux responses are also studied in abnormal heat transfer conditions, i.e.scale. Finally, through analysing the fluctuations of heat flux measurements, an optimised thermocouple layout is proposed. The experimental and analytical results lay the foundation for an intelligent mould with online detection of defects, adjustment of operational parameters, optimisation of the monitoring system and even prediction of abnormal heat transfer.

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