| With the rapid development of science and technology,continuous casting technology has become increasingly mature.The production of copper billets by horizontal continuous casting has become the mainstream in the copper strip industry.The slab produced by horizontal continuous casting method has good quality,less investment in production equipment,low cost and high production efficiency.With the continuous cold rolling process,the short process,high-precision and high-performance preparation and processing of copper sheet and strip can be r ealized.At present,with the rapid development of the copper strip market in China,higher requirements have been put forward for product quality and qualification rate.However,the defects of horizontal continuous casting billet of copper strip and the stability of process parameters have become the main technical difficulties affecting product quality.The mold is an important part of the horizontal continuous casting production line,which plays a key role in controlling the surface quality and internal defects of the slab,and directly affects the final product quality.In this paper,the horizontal continuous casting mold of copper strip slab is taken as the research object for modeling and simulation research.The influence rules and internal mechani sms of cooling water parameters,casting process parameters,graphite mold performance and structural parameters on the temperature field of each wall,slab temperature field and microstructure field in the mold are analyzed.The improvement scheme of mold structure and process parameters is proposed,which effectively improves the quality of copper strip horizontal continuous casting slab and product qualification rate.The main work of this paper is as follows:Firstly,1:1 modeling was carried out accord ing to the structural parameters of the mold at the production site,and the finite element model of the horizontal continuous casting process was accurately established.The "dual field" synchronous coupling simulation analysis was carried out on the cooling water flow field and the slab temperature field in the mold through the FLUENT function module in ANSYS.The influence of the pressure change of the cooling water inlet and outlet on the temperature field of each contact surface in the mold and the sla b temperature field was compared.Secondly,by adjusting the diameter of the water inlet at the lower end of the copper sleeve,the cooling strength of the lower surface of the slab is improved,and the grain of the slab is refined;By designing the groove structure at the edge of the graphite plate,the uniformity of the temperature distribution on the slab surface is improved,the bending radian of the slab crystal line is reduced,and the surface segregation is reduced.Then the influence of casting spee d change on the solidification behavior of horizontal continuous casting slab was studied,and the changing laws of temperature field,liquid cavity depth,cooling rate,etc.in the mold under different casting speed conditions were revealed,and the evolu tion rules of slab surface and section structure under different casting speed were analyzed based on industrial experiments.Finally,through numerical simulation and industrial production experiments,the influence of different graphite mold materials an d physical parameters on the quality of the slab was investigated,and the influence of different graphite mold density,thermal conductivity,etc.on the interface heat transfer coefficient and the slab temperature field was revealed.The research content of this paper includes finite element theoretical simulation analysis and production field test verification.The research results are helpful to further understand the heat exchange process and interaction between the cooling copper sleeve inside the mold and the billet in the copper slab horizontal continuous casting process,and can provide some reference for the selection and optimization of process parameters in the actual production process. |
PDF Full Text Request