| 摘要 |
<p>PROBLEM TO BE SOLVED: To automatically and smoothly tap molten metal even by an unskilled person without damaging a drill and causing the clogging with melt by automatically retracting the drill of a drilling machine that excavates the mud material of a tap hole for opening a runner to the outside of the tap hole at an appropriate timing after the runner is opened in the tapping of the molten metal from a melting furnace. SOLUTION: In the tapping method of molten metal M, a mud material 25 being filled into a tap hole 11 is excavated by a drill P of a drilling machine 21, and a runner is formed, thus extracting the molten metal M in a melting furnace body 3. In this case, opening speed V of the runner by the drill P of the puncher 3 is detected, the through-hole of the runner by the drill P is discriminated according to change in the detected opening speed V, and the drill P of the puncher 21 is retracted to the outside of the tap hole 11 based on a discrimination signal Q.</p> |
