The paper improves the calculation methodology of metal temperature loss during hot rolling process at continuous mills. The proposed methodology can be implemented at hot strip mills with various in-line equipment arrangements within the temperature ranges appropriate for processes simulation of hot rolling, normalized rolling and Thermo-Mechanical Control Process of carbon and microalloyed steels. It provides engineering analysis of unaccounted temperature losses of feed by means of radiation and convection, which, in the first time, through the time factor, additionally accounts for strip motion speed factors, roller table length and feed length, and also length of rolls contact arc with metal. The accountability of the above mentioned factors in the various compositions depending on the rolling method increases the engineering simulation accuracy, ensures the versatility of the elaborated method with respect to different types of mills and makes the scientific novelty of the study. The equations were developed to calculate the metal temperature loss while coiling at the CoilBox unit. The equations accounts for the influence on the temperature of strip length, coiling and uncoiling speed, strip thickness, inside radius of the reeling coil, the time the feed rests being coiled. The improved model was verified based on actual data.

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In this work the developing manufacturing technology for 4mm thick plates produced of 220mm thick continuous cast slabs instead of 150mm thick slabs for mill 3200 (Metinvest Trametal SpA) is shown. The technology has been developed with the mathematical model of the rolling process. Тhe rolling technology for manufacturing of plates (4×3125×16000mm) from slabs (217×1355×780mm) has been developed. The developed technology makes it possible to reach the final rolling temperature of 826oС, which provides a good opportunity to use it for plate production in keeping with the hot, normalizing, controlled rolling technology or TMCP, and does not limit the existing grade mix. It is possible to use for production of 220mm thick slabs instead of 150mm thick slabs.

The mathematical model of hot-rolled coil rolling at the Steckel mill (Ferriera Valsider SpA) has been thoroughly investigated in the paper. There has been made a verification of the developed model to use it for the rolling technology design. The influence of the stand stiffness has also been taken into account. When simulating rolling temperature conditions, an average error was within the range from 8.27 to 9.11% at the mill 3170 and from 0.003% to-0.92% at the mill 1780. When simulating rolling force, an average error was within the range from 0.5% to 5.7% at the mill 3170 and from-4.89 to 6.59% at the mill 1780. The equation has been obtained, and the comparison of calculated stands stiffness has been made at the mill 3170 and 1780.There has been determined influence on the actual measurement of the pre-treatment temperature for the feed processing by descaler, which results in significant errors compared to the calculation results.

Тhere has been developed technology, and pilot batch of hot rolling coils (6×1500 mm, steel grade S355MC) has been produced using thermo-mechanical controlled process (TMCP) for the wide-strip rolling mill 1700. The integrated technology for TMCP coil production (steel grade S355MC) has been firstly developed for the rolling mill 1700 in accordance with EN 10149-2. Air cooling for coils to 450°C after coiling has been firstly used in the developed technology, which provides for decrease in air scale and improvement of surface quality for the customers. It is possible to manufacture rolled products up to 6×1500 mm (steel grade S355MC) in accordance with EN 10149-2 using the existing equipment without exceeding the existing process constraints during its operation and without upgrading. It is possible to further master the rolled products, which are manufactured according to the TMCP technology.