| 摘要 |
<p>PURPOSE:To prevent the generation of heat scratch by lowering a rolling speed and changing the load distribution of motors to increase an interstand tension and return the rolling speed to its original speed when the temperature of a steel strip at the outlet side of a mill reaches a prescribed high temperature zone. CONSTITUTION:The temperature TA of a steel strip in rolling is measured by a thermometer 2 provided to the outlet of a mill 1, and is sent to an operation circuit 3. The difference between the measured temperature TA and a set temperature TO, safe from scratch and fixed separately depending on the materials of strips, is operated by the circuit 3 and is sent to a decision circuit 4. The rolling is continued when TA is lower than TO, and its speed is increased because TA is safe from the heat scratch; but when TA becomes higher than TO, the presence of danger from generating heat scratch is decided, and its result is sent to a rolling-condition control circuit 5, to lower the rolling speed and to increase the load distribution of motors and the interstand tension. Thereafter, the rolling speed is returned to the original one. By this mechanism, the generation of heat scratch is prevented and the production efficiency is improved.</p> |
