Study On Cavity Type Design Of New Type Billet Continuous Casting Mould

As the core component of the continuous casting equipment,the crystallizer undertakes the task of solidifying and forming liquid steel.A reasonable shape of the cavity can reduce the stress strain in the mold shell in the mold,and plays an important role in improving the quality of the slab.In this paper,different solidification and shrinkage laws of different steels in the crystallizer were studied,and a new billet mold suitable for pouring different steels was developed.Combined the solidification shrinkage characteristics with deformation mechanism of the shell,setup the finite element model for mold casting with a 150 mm x 150 mm billet.Study the slab temperature field and deformation law under different drawing speed and the steel grade in the form of heat transfer coefficient converted into heat flux boundary to solve the heat flow density.Get the slab temperature field in the crystallizer distributions and the rule of the shell solidification shrinkage.On the one hand,a three-dimensional finite element model of copper tube is established to simulate the temperature field of copper tube under different steel and pull speed.On the other hand,establish finite element model of copper plate deformation.Thermal analysis result as the initial condition is added to the copper plate model to get the crystallizer copper tube deformation law.All of this can provide certain reference for the design of the mold cavity shape.Combined the influence factors of solidification shrinkage of casting billet with the analysis of the deformation rule of copper pipe and slab,create the function expressions of transverse and longitudinal center curves of the crystallizer.The curvature of the curves in the transverse and longitudinal centers is continuous change,which improves the non-uniform deformation.The cross section boundary curve is transformed from the upper convex shape to the lower jaw line to satisfy the contraction of the corner of the blank shell faster than the surface center.The longitudinal center curve is designed by different steel shrinkage rules,and it is modified by adjusting the taper function in the corner to make the cavity better suitable for the shrinkage of the casting billet.Finally,the rationality of the new cavity shape was verified from the taper and strain rate.