Study On The Mould Taper Of Billet Continuous Casting

With the advancement of the casting process and the improvement of the products quality requirements, many experts and producers pay more and more attention to the optimization of the mould taper. In this study, the mould taper of 150 billets was optimized by thermal-mechanical finite element model, which was built by ANSYS. A 2D thermal-mechanical finite-element model was developed to analyze the thermal-mechanical behavior of the solidifying shell in the continuous casting of steel and a 3D thermal-mechanical finite element model was established to optimize the mould taper and the curve taper mould was further recommended.A mathematical billet thermal and solidification model was applied to compare the effect of casting speed and super heat, the results show that high speed casting result in the higher temperature at the exit of the mould, the thinner shell growth and the smaller shell shrinkage. The great impact of continuous casting speed on the stress and strain is proved .In addition, The results show that surface temperature is a bit increase, shell shrinkage has less change and the shell's thickness in casting solidification is thinner as change of superheat degree from 15℃to 25℃at the same casting speed.The result of simulating the temperature distributions and distortion of the mould shows that the temperature and the distortion of the mould hot and cold face are heighten as the increase of casting speed; the change of superheat degree from 15℃to 25℃cause higher temperature at hot face of mould, but temperature at cold face and mould distortion is almost same.The ideal taper of the mould is gotten by general consideration on both the shell shrinkage and the distortion of mould produce. The study shows that it is important in mould design to determine how the billet and mould interact. To do this, one must compare the billet dimensions with the hot distorted mould dimensions. The casting speed has significant effect on the taper of the mould. As the increase of casting speed, the mould of the same steel needs minor taper. The results show that the taper changes slightly with the change of super heat. This paper also compares the difference between center taper and corner taper of the mould, the result show that corner taper is steeper at the top of the mould, whereas the taper at the bottom of mould is little difference.