If the temperature of workpiece is 450 °C, the
rolling force decreases from 4.5 to 1.2 kN. This indicates that when the size of rollers is large, their temperatures
would have appreciable effect on the reduction of rolling load. However, it is clear that the effects of rolling
reduction and workpiece temperature on the reduction of rolling load are larger than that of roller temperature,
which can be seen easily from the change of colours.