Improvement of the technology for the production of high-quality thick-plate products from microalloyed pipe steels based on the application of the effective technological compensation methodology

Large-diameter pipes are one of the most popular types of metal products consumed by the Russian fuel and energy complex. To meet the needs of PJSC Gazprom and other energy companies, high-quality thick plates from microalloyed pipe steels (MAPS) are required. It is known that the level of properties of such products is preliminarily formed and successively changed at the stages of smelting and continuous casting of MAPS and further - in the processes of heating, rolling and cooling of heavy-plate products. It is shown that “MAPS - thick plates” is a complex technological system in which a multifactorial process of sequential accumulation of the required quality indicators of intermediate and finished products is implemented. To improve this system, the concept of effective compensatory impact has been formulated and a special toolkit for scientific analysis and solution of technological problems has been developed - the methodology of effective technological compensation. A complex of mathematical and physical models has been describe to determine effective compensatory technological influences in the “MAPS - thick plates” system. The technological parameters of the production of heavy-plate products have been calculated to compensate for the targeted reduction in the content of alloying elements in MAPS of strength classes K56-K65. A method of searching for resource-saving compensating modes of plate rolling of continuously cast slabs from MAPS with surface cracks has been developed. The choice of compensating modes of asymmetric deformation of continuously cast slabs with a temperature gradient along the thickness is theoretically substantiated. The concept of intensifying the deformation effect on the central layers of metal in the production of thick plates from continuously cast slabs with an increased level of axial chemical heterogeneity has been expanded.