| 摘要 |
<p>PURPOSE:To reduce sheet thickness deviations at a lock-on time and to improve the sheet thickness accuracy by controlling a screw position by use of a lock-on load. CONSTITUTION:From a start of rolling of a rolled stock by a rolling mill until a start of AGC, loads Pi(P1, P2-Pn) and screw positions Si(S1, S2-Sn) are measured by a load cell and a position detector at (n) points, respectively. A thickness difference hi=hi-hm between an outlet side sheet thickness hi at respective measuring points and a target sheet thickness hm are found. Screw positions are controlled by use of a controlled variable S described by the equation after the start of AGC. Where, S: controlled variable for screw position, Sn: screw position at a start of AGC, P: rolling load at controlling time, K: mill constant of the rolling mill, M: plasticity coefficient, alpha: coefficient, beta: coefficient. Hence, a sheet thickness deviation h at a lock-on time is minimized, the time necessary to make the h be zero, and the sheet thickness accuracy is improved.</p> |
