Rolling reduction control method under large liquid core pressure

Abstract

The invention discloses a rolling reduction control method under large liquid core pressure. A roller-type rolling mill is arranged at the position, with a liquid core, of the horizontal segment of a continuous casting machine, wherein a casting blank is not completely solidified at the position. The liquid core rate delta is obtained at the position of the rolling mill, and whether the liquid core rate delta is larger than 0 or not is judged. If the liquid core rate delta is larger than 0, the rolling mill conducts rolling under the large liquid core pressure on the casting blank, wherein the rolling reduction of the rolling under the large liquid core pressure is larger than or equal to the minimum rolling reduction delta H min, and the minimum rolling reduction meets the equation that delta H min=max [H*(epsilon v + epsilon l + delta), mu*S]. According to the rolling reduction control method, center porosity, segregation, internal cracks and the like of the casting blank can be removed, the quality of the casting blank is improved, and internal organization is refined; the internal quality of the rolled casting blank is remarkably improved, the density of the casting blank is improved, the linear shrinkage percentage of cooling from high temperature to room temperature is at least reduced by 1.5%, the model control is easy, and the rolling reduction control method is easy to implement.

Description

technical field [0001] The invention relates to a method for controlling metal rolling, in particular to a method for controlling the rolling reduction of liquid core under large reduction. Background technique [0002] Liquid core rolling refers to rolling when the core of the slab is liquid or semi-solid. This method uses the residual heat of continuous casting to roll the slab without cutting it. The heat loss of the slab is small, and the essence of rolling is core. The upper liquid core is squeezed back to the rear liquid cavity, and the dendrites in the crystallization area of ​​the core are broken and recrystallized. For example, in the Chinese patent literature with the authorized announcement number CN102189102, the announcement date being February 6, 2013, and the title "A method for online thickness-adjusting roll-type large-reduction liquid core rolling for continuous casting machines", in the slab continuous A large-diameter two-roll rolling mill is installed a...

AI Technical Summary

Problems solved by technology

[0003] Although for the above-mentioned large-reduction liquid core rolling method, the literature has announced the implementation of 30-90mm reduction, but it is still difficult to control the amount of rolling reduction for different thicknesses and different liquid cores.

The difficulty lies in: how to control the minimum reduction in the case of different liquid core thicknesses and different thicknesses of slabs, in order to remove central porosity, segregation, internal cracks, etc., improve the quality of slabs, and refine the internal structure

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