Research of the cutting process of rolled section steel on rail-beam and large-size rolling mills

Abstract

The aim of the work is to study the conditions of cutting the last bar of the measured length and the remaining rolled product under conditions of unstable rolling length, which are realized as a result of fluctuations in the sizes of the blanks and the temperature regime of rolling.
The roll is cut into bars of the same measured length according to the order, but fluc-tuations in the length of the roll result in the last bar being either longer or shorter.
If the bar is increased, then the amount of the remainder may be too large and, in order not to lose suitable rolled product and not to transfer the remainder to waste, the last bar and the remainder are cut into two bars of normal length.
The work shows that the amount of the remainder, starting from which it is necessary to cut into two bars of normal length, is determined by economic feasibility, which is more ex-pensive – a bar of measured length and a remainder or two bars of normal length.
An expression is given for obtaining the residual value depending on the size of the bar of the measured length, the cost coefficients of the bars of the normal length and waste. For the conditions of rolling the channel 24 on the mill 800, the remainder value is 0.86 m.
It is shown that to ensure maximum profit depending on the remainder value, the last bar of the measured length can be cut in the following ways: into a bar of the measured length and the remainder, into two bars of the normal length or into a bar of the measured length and a bar of the normal length.