| 摘要 |
<p>PROBLEM TO BE SOLVED: To definitely detect the edge of a hot slab by positioning a detector so that the angle between the optical axis of the detector and the moving direction of a slab can become a prescribed value in the same vertical plane and detecting the radiant energy in the vertical plane. SOLUTION: Hot metal detectors HMD-1 to HMD-3 are positioned so that the angles between the optical axes 3 of the detectors and the moving direction of a slab 1 can become 40 deg.-85 deg. (preferably, 60 deg.) in the same vertical plane. As a result, the detecting error of the slab 1 can be reduced, because the emissivity of the end face 6 of the slab 1 increases because of scales falling down from the end face and the probability of the reflecting angle of the end face becoming coincident with the Brewster angle is high. When the slab 1 is transferred toward a roughening mill 10 from the downstream side, the detector HMD-1 detects the end face 6 of the slab 1 and, when the slab 1 is transferred to the upstream side through the mill 10, the detector HMD-3 detects the end face 6. When the slab 1 is transferred toward the mill 10 from the upstream side, the detector HMD-2 detects the end face 6. The detectors HMD-1 to HMD-3 transmit their output signals to a process computer, etc., and the computer controls a prescribed process.</p> |
