Experimental study on inclusion absorbed by the absorption bar in liquid steel

Abstract

The refractory absorption bar is inserted into the submersed nozzle by a stopper to absorb the inclusion flowing through the nozzle and increase the cleanness of liquid steel during the continuous casting process. Based on the high-temperature hot-state experiment, the influence of the groove structure of the absorption bar on the inclusion absorption rate in liquid steel is analysed. Experimental result shows that when the groove direction of the absorption bar is perpendicular to the rotating direction, the optimal groove depth is 3 mm, the maximum thickness of the absorption layer is 362.9 μm and the maximum absorption velocity is 0.19 μm s⁻¹; when the groove direction of the absorption bar is parallel to the rotating direction, the optimal groove depth is 2 mm, the maximum thickness of absorption layer is 404.3 μm and the maximum absorption velocity is 0.22 μm s⁻¹. When the groove depth is determined, the absorption rate when the groove direction of the absorption bar is parallel to the rotating direction is higher than that when the groove direction of the absorption bar is perpendicular to the rotating direction. In addition, the number of grooves on the absorption bar is positively proportional to the absorption capability. An inclusion absorption capability model is established based on the multiple regression method and the absorption capabilities of different absorption bars are evaluated. This experiment has provided significant data supporting smelting of clean steel.