在950/800大型轧机上轧制40号槽钢的常规孔型系统采用9孔成型,其中两个孔在950开坯机,1～3孔在第一架三辊800轧机上,第4～6孔在第二架三辊800轧机上,而第7孔在850精轧机架上。3～6号孔是半闭式的(可控制的)。在用此孔型系统轧制40号槽钢时,不能保证形成具有稳定槽缘高度的槽钢。在通过开口孔2和4时,轧件处于三辊800轧机上水平辊中, In the 950/800 large rolling mill on the 40th channel conventional hole system using 9 hole molding, of which two holes in the 950 open blanks, 1 to 3 holes in the first three-roll 800 mill, the first 4 ~ Six holes are on the second three-roll 800 mill, while the seventh hole is on the 850 finishing mill stand. The holes 3 to 6 are semi-closed (controllable). When channel 40 is rolled with this hole system, it is not guaranteed that a channel with a stable groove height will be formed. While passing through the openings 2 and 4, the rolling stock is in a horizontal roll on a three-roller 800 mill,