Analysis of the Thermal Contraction of Wide-Thick Continuously Cast Slab and the Weighted Average Method to Design a Roll Gap

A three-dimensional (3D) thermo-mechanical coupling model is established to describe the uneven solidification and thermal contraction behavior during the process of continuous casting of wide-thick slabs. To improve the accuracy of the simulated results, the thermal and mechanical material properties are calculated with the weighted average phase fraction method, and the boundary conditions is derived from the actual measured water flux distribution. The predicted heat transfer results are verified with the measured shell thickness and surface temperature. With this model, the non-uniform heat transfer and thermal contraction behavior under different casting conditions are investigated. Finally, a weighted average method to design the roll gap is proposed and implemented into practical production. The results from the plant after the roll gap optimization indicate that the internal quality of the wide-thick slab is dramatically improved and that the casting operation is more stable.