ANALYTICAL CALCULATIONS OF SOLIDIFICATION AND COOLING PROCESSES IN LARGE-TONNAGE COMMERCIAL INGOTS. REPORT 2. THERMAL CONDITIONS OF INGOT IN HEAT–TECHNOLOGICAL PROCESSING CHAIN FROM CASTING TO FEEDING TO A ROLLING MILL

The article is devoted to the development of the analytical design procedure of solidifi cation and cooling of large-tonnage bloom ingot. As the analysis result of the reference model and the received solutions, a universal way has been worked out to calculate the mode of solidifi cation and cooling of ingot in the industrial conditions from the casting to charging into the cell of soaking-pit furnace. The satisfactory matching with the results of the industrial experiment has been shown when using the analytical nomogram-graphical method of the calculation. The way of calculation allows defi ning the total time of ingot solidifi cation and the surface temperature in the process of solidifi cation, condition of crystallization front in a set moment of time, duration of cooling of the overheated melt and other parameters. When using the analytical and nomogram-graphical method of the calculation, the preparation technology of industrial bloom ingot to the heat has been improved, as well as corrected the operating heating mode of ingot with the increased heat content (liquid kernel), which has been tested and implemented in industrial conditions. Realization of the mode has shown the heating time reduction of ingots and the decrease of fuel rate.

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