Research On Heat Transfer And Structure Optimization Of Roller During Twin-roll Steel Strip Casting

Twin-roll casting strip process studied by countries around the world in the last twodecades for its advantages, such as its short process, low energy consumption and higherstructure property of material and so on. However, there are still many challenges to dealwith, for example the complex boundary of periodic heat transfer between casting rollersand molten pool, the structure of the casting rollers and the optimal cooling way undergood quality of the strips and good organizational performance, accurate mathematicalmodel of rolling process, the optimum heat roller and the material of roller with higherfatigue life, casting roller semi-solid production of the flow of liquid and solid phasecomposition, the electric control system with high control precision, etc. Therefore, thisarticle will focus on some of these issues. In this paper, the main work and research resultsare as follows.(1)Through analyzing the heat transfer mechanism of roll casting process and thecharacteristics of solidification, considering the initial position of solidification andcasting slab thickness, and combining crystallization roller thermal equilibrium, this paperproposes a new general research method on studying about the thermal boundary of theheat roller contact surface. This method can get instantaneous heat flux of the rollersurface contact, and the accuracy of instantaneous heat flux is verified by simulation andexperiment. And this method have great significance to the double roller rolling theoryresearch.(2)A two-dimensional coupled thermal-mechanical FEM theory of the casting roll isestablished. The temperature field and thermal stress field of roller are studied with thefinite element analysis by secondary development of Marc software. With this method, itgets influence law of casting roll temperature field, thermal stress field considering the rollsleeve material, casting speed, cooling water velocity, the angle between the cooling waterhole, water hole from the roll surface distance, layer thickness. The paper get the mutualinfluence between the structural parameters of the relationship, and to determine thereasonable range of parameters. (3)The effect of temperature field of casting roll with the casting process parametersis preliminarily to determine by orthogonal test method. Then by improving the structureof waterway and the way of watering of the casting roll, the cooling intensity and thecooling efficiency is increasing, roll surface temperature is uniform. The flow of water issimulated by FLUENT software, and finally required and reasonable construction ofcasting roller is proposed.