| 摘要 |
PURPOSE:To decrease the generation of seam flaws and to improve the quality of the end faces of a stock to be rolled and the yield thereof by forming a forged layer to the end face of said stock in either or both of the sizing stage of an ingot and the adjusting stage prior to cross rolling. CONSTITUTION:The rolling force in the transverse direction may be exerted during sizing rolling in succession to casting of the steel ingot or during the shape adjustment rolling intended to eliminate the difference in the thickness deviation of the ingot prior to cross rolling of thick plate rolling and may be by continuous pressing in the respective positions in order to forge the end faces of the ingot. The required rolling force in this case is 3 times the yield stress in plane strain of the stock at the working temp., for example, about >=10 kg/mm<2> when an ordinary carbon steel is rolled down at 1,100 deg.C. The generation of the seam flaws is thus considerably decreased, by which not only the improvement of the yield in production of the thick plate but the remarkable improvement of the end face quality are made possible.
|
