TAP HOLE OPENER FOR BLAST FURNACE

PURPOSE:To enable safe and efficient hole opening operation by controlling the letting out speed of a consumable oxygen lance and the position of the lance with respect to a tap hole in the stage of straightening and letting out the lance and opening the tap hole. CONSTITUTION:The consumable oxygen lance 12 wound on a take-up drum 14 is straightened by a straightening and letting out device 15 and is let out to the tap hole 17. The tap hole is opened while oxygen is fed thereto. a swiveling arm 21 lifts a lance letting out device 13 freely turnably by means of a lifting rod 22 and is freely turnably driven by an air motor 25. The swiveling arm 21 is made freely turnable by a clutch mechanism 26 with a resetter when the swiveling arm 21 turns from the standby position to a position ready for hole opening. The force from a pressing force applying device 27 is exerted to the arm 21 through a tension wire 28 so that the arm is directed at all times toward the tap hole 17. The swiveling arm 21 turns toward the tap hole 17 when the melting speed increases so as to exceed the letting out speed of the lance 12. The rate of the air to be supplied to the air motor for driving the letting out roller is then changed to decrease the letting out speed of the lance 12.