| 摘要 |
<p>PURPOSE:To make the steel tube having wall thickness and the outside diameter of a target with high accuracy. CONSTITUTION:A relation of a thickness deviation signal and forward slip or a pitch diameter is set in advance, and in accordance with said relation, the advance or the pitch diameter in a control stand is corrected continuously in accordance with a thickness deviation of a skelp to be controlled, and by controlling the number of revolution of each stand in accordance with a mass flow constant theory, a wall thickness fluctuation in the longitudinal direction of a tube is controlled, a wall thickness fluctuation in the longitudinal direction of a butt welded steel tube is prevented, and the yield is improved and the steel. tube of high accuracy is obtained.</p> |
