| 摘要 |
PURPOSE:To uniformize the erosion of a lance and to prolong the life of the lance by rotating the lance with its axis as the center. CONSTITUTION:While a lance 11 is rotated with its axis as the center by a motor 12 through gears 20 and 21, gaseous Ar 14, etc., is supplied to the lance 11 through a pipe 22, a sealing member 15 and a hole 23 and blown into the molten steel 18 in a ladle 19 from a hole 17. Besides, the upper and the lower position of the lance 11 are regulated in accordance with the level of the melt 18 by lifting a lifting carriage 16 up and down. The molten steel is violently agitated in the ascending zone of the bubbling gas formed by the gas 14 blown into the molten steel 18 and the lance 11 is eroded. However, the peripheral surface of the lance 11 is uniformly eroded by the rotation and further the bending of the lance 11 due to the buoyancy of the molten steel 18 is prevented. By such a structure, the life of the lance 11 is prolonged. |
