Study On Mould Taper Of Wide And Thick Slab Continuous Casting

With the development of continuous casting technology, the wide and thick slab billetquality requirements are increasingly high, people have put various efforts in improvingquality of billet, as the place of initial solidified shell, the mould is attracting more and moreattention by people naturally, and the mould taper play a key role in it.In this paper, based on the specific equipment and process parameters of wide andthick slab caster in a domestic steel factory, a two-dimensional non-steady of heat transfermathematical model of wide and thick slab continuous casting process and shrinkage ofbillet. By using the large general finite element software ANSYS, the solidification processof continuous casting slab in mold has been simulated. The temperature distribution ofbillet in solidification process in mold, shell growth, stress and strain and shrinkage hasbeen calculated in different casting speed, superheat and the slab thickness, on the basis thebest mould taper has been designed under various process parameters. By comparison withthe reality, the calculated result is accurate, indicating that the calculation modelestablished in this paper have some practical value.The calculation results show that, the casting speed has larger effects on temperaturechanges of billet in mold.Higher casting speed means higher billet temperature during themold, thinner shell and smaller shrinkage.And casting speed also has greater effect on the slabstress strain. And the slab thickness has little influence on temperature change of billet inmold during solidification.When the increased from20℃to30℃, the temperature of slabwill increase in some degree,the shell will become thinner, and Superheat has little effecton the slab stress strain and shrinkage, and the influence on the stress is larger than on thestrain.When the slab thickness increased from200mm to300mm,the slab temperaturevaries little in the mould,and the stress and strain of billet and shrinkage of billet also haslittle changes.Based on the solidification shrinkage, the reasonable mould taper has been designed.Research shows that, in general, the effects of casting speed on the mould taper is larger, ifcasting speed is larger, that smaller taper is needed, if casting speed is smaller,that larger taper is needed. The upper part of the mould needs larger taper, the lower needs smaller taper,and the upper part of mould that near meniscus taper has larger variation than the lowerpart of mould in different casting speed.The Superheat and slab thickness has little effecton the mould taper.