Analysis On Continuous Casting Slab Solidification Temprature Field And Force Of Bending And Straightening Process

Heat transfer and solidification of the high temperature molten steel and bending andstraightening with liquid core proceed at the same time during continuous casting process,that is temperature change and forces intercoupling affect the quality and efficiency ofcontinuous casting slab. Therefore it’s of great theoretical and practical significance onimproving production, controlling and improving the quality of slab to analyze thetemperature and force condition of slab during bending and straightening.In this paper, three-dimensional slab model of heat transfer and solidification wasestablished and time-varying thermal boundary condition was applied to each unit. Finiteelement analysis was used to simulate the three-dimensional temperature field of slabwhen passing through the crystallizer, the foot roller district and the secondary coolingzone. The curve of temperature changes over time of the characteristic point on thecross-section of slab as well as the thickness of the solidified shell was provided.There should be no longitudinal thermal conductivity for three-dimensional slabmodel before entering the crystallizer, a “virtual temperature method” was proposed tocontrol the different heat transfer status of the slab before and after entering thecrystallizer and prevent the longitudinal thermal conductivity. That is: setting a coefficientof “virtual temperature” higher than the pouring temperature to zero in setting up the curveof the thermal conductivity changing with temperature. And the temperature of slab out ofthe crystallizer was set to “virtual temperature” while the slab inside the crystallizer wasset to pouring temperature, which enabled the normal cooling heat transfer process. Thismethod made the temperature field analysis more close to the real pouring situation andthe accuracy of three-dimensional temperature field analysis was improved.In this paper, a new continuous casting machine curve was proposed and analyzed.Three-dimensional model coupled thermo-mechanical of the continuous casting slab wasestablished. Under the consideration of static pressure of the steel and gravity, the stress ofthe bending straightening process of slab was analyzed using three-dimensional finiteelement thermal-mechanical coupling analysis. The distribution law of stress, strain andstrain rate was acquired and the rationality and superiority of the new continuous casting curve was verified.