| 摘要 |
<p>PURPOSE:To obtain with a high accuracy a wall thickness and an outside diameter of a tube stock by controlling a rolling condition of a following material in at least final two stands for finish, based on a measured value of a preceding material. CONSTITUTION:Before rolling a following tube stock, a rolling load distribution and a roll gap distribution are derived with regard to finish roll stands 37, 38, based on a signal related to a rolling load and a roll gap of the time of preceding rolling, which have been inputted from load cells 7, 8 and selsyns 17, 18. Also, an outside diameter DB of a mandrel bar 2 to be used in the next time, and roll holiber sizes RI, SI are derived, and they are inputted to an arithmetic and control unit 4. When rolling the following tube stock, the arithmetic and control unit 4 derives a roll gap and the number of revolution of the svel related to the finish roll stands 37, 38, and executes a control so as to obtain a target value. In this way, the wall thickness and the outside diameter can be obtained with a high accuracy.</p> |
