Magnitogorsk Iron & Steel Works (Magnitogorsk, Russia):

Prokhorov S. V., Chief Metallurgist
Kazakov A. S., Leading Specialist, kazakov.as@mmk.ru
Yurechko D. V., Head of Laboratory
Moshkunov V. V., Engineer Technologist
Filippov A. V., Engineer Technologist

Usage of rational cooling in the secondary cooling area is required for provision of stable technological process of steel casting and quality improvement of internal structure in continuously cast billet. Parameters of designed and pilot procedure of secondary cooling for 08Yu steel are presented, as well as relationship between torque variations and billet cooling intensity for different variants of pulling speed. The developed equations show that rize of total torque on roll drives occurs after achieving certain level of cooling intensity. In order to confirm the obtained relationships, several melts of low-alloy steel 17G1S-U have been cast into slabs with 2,320 mm width. The results of comparison of two collections of values of actual and calculated torque on driven rolls of continuous caster are analyzed. The presented data allow to testify that both collections can be estimated as belonging to one general aggregate. Therefore, obtained relationships can be used for calculation of required cooling intensity in order to achieve minimal torque for stable process of billet contunuous casting with acceptable precision. The conducted investigations have shown that usage of intensive cooling in the secondary cooling area leads to deacrease of buckling of billet surface, of crack propagation and allows to prevent urgent downtimes of the continuous caster due to retarding of billet pulling.