Experimental study on accelerometer-based ladle slag detection in continuous casting process

Abstract

The share of continuous casting method is increased day by day among steel production methods. In continuous casting plants, steel production is carried out using BOF (basic oxygen furnace) or EAF (electric arc furnace). During the journey of the liquid steel through whole steelmaking stages, the carryover ladle slag can turn into one of the most detrimental element in casters. It is known that a carryover ladle slag consists of mainly oxides such as CaO, SiO2, Al2O3, and MgO. Carryover slag has to be kept under control otherwise one can end up with negative results. With the development of sensor technology, the detection of carryover ladle slag becomes possible at the end of heats. The main advantage of the sensor type is early detection over a human-controlled system. A few seconds can make a big difference on safety, quality, yield, castability, and cost when the casting sequence lengthens due to the amount of slag. Nowadays, steel production via BOF which is performed with very low profit margins makes it important to solve this problem. Especially steelmaking produced by BOF, the detection methods of carryover slag are human controlled, electromagnetic based, ultrasonic based, image processing based, acoustic based, and vibration based. In this study, it is seen that the vibration-based detection system has many advantages over others when considering investment cost, product quality, castability, and accuracy. The scope of the study aimed to design a vibration-based carryover slag detection system on BOF steel production line. The designed detection system has an accelerometer, data processor, and controller system. After the experimental study, the cost, the product quality, and the productivity analyses were performed for the condition of use and non-use of the vibration-based detection system. At the end of this study, it is seen that the vibration-based carryover slag detection system is affordable and feasible.