| 摘要 |
PURPOSE:To control waving due to web buckling favorably by rolling under the condition that the backward factor of flange exceeds the backward factor of web when rolling a material to be rolled at the time of execution of active rolling-down from the outside of the flange of the material to be rolled. CONSTITUTION:In the case the shrinkage of width dimension of web is increased, bulging, i.e., partial thickening is generated at both ends of web and these parts show especially high elongation percentage at the point of time of rolling with horizontal rolls. The unbalance of elongation between both end parts of web and the flange part and the unbalance of elongation between both end parts of web and other parts are generated. The deterioration of elongation balance is reduced by rolling under the condition that the backward factor of flange that is shown with the formula I is made larger than the backward factor of web that is shown with the formula II. In this way, waving due to web buckling is favorably controlled, the range preventing from buckling is extended and the rolling of H-shape steel with the wide range of size is possible by setting up roll once. |
