Abstract
The length of the rolling mill line and the slab temperature change are theoretically compared between the quasi continuous type equipped with 3 rougher mills, of which the first one is reversible, and 6 finisher mills and the quasi continuous 4 passes type equipped with 2 rougher mills, of which the first is reversible, and 6 finisher mills for a mathematical model that a slab is rolled from the initial thickness 230mm to the final thickness 2.5mm.
In the quasi continuous 4 passes type, the total length in the roughing process can be shortened to about 60% compared with the case of the quasi continuous type. For a given reheating temperature, the slab temperature at the entrance of the first finisher remains much higher in the quasi continuous 4 passes type so that the reheating temperature can be reduced over 100°C. Finally, one conclusion is that the quasi continuous 4 passes type is much profitable not only for the shortness of the rolling mill line but also for the energy saving in the rolling process.
