| 摘要 |
PURPOSE:To manufacture a unidirectional silicon steel plate having superior surface properties by slowly cooling a silicon steel slab contg. Si, Mn and S and/or Se taken out of a heating furnace to a specified temp. or below and conveying the slab to a hot rolling mill by means of table rolls. CONSTITUTION:A silicon steel slab contg., by weight, 2.5-4.5% Si, 0.03-0.10% Mn and 0.005-0.10% in total of S and/or Se is heated in a walking beam type heating furnace until the underside of the slab is heated to >=1,270 deg.C. The heated slab is taken out of the furnace and slowly cooled at <=3 deg.C/sec cooling rate until the under-side of the slab is cooled to <=1,250 deg.C. The slowly cooled slab is conveyed to a hot rolling mill by means of table rolls. Thus, the occurrence of linear spills is prevented, and a silicon steel plate having superior surface properties can be manufactured. |
