Research On Hot Backward Extrusion Process Of Copper Tube For H Section Steel Conticaster Crystallizer

With the development of the national economy,the demand for H profiles and other profiles has increased substantially.Shaped blank continuous casting can greatly improve production efficiency and reduce energy loss,and has become the main production mode of profile materials in recent years.The demand of high quality mould copper tube for billet continuous casting is also increasing.The hot extrusion process is used to produce the mould copper tube in the blank continuous casting.The irregular shape and blank size lead to the complexity of the metal flow law in the process of hot backward extrusion.Therefore,to reduce or avoid the uneven port of the extrusion parts becomes an important proposition in the manufacturing process of the mould copper tube.It has important theoretical significance and practical reference value for reducing mechanical cutting quantity,improving material utilization rate and reducing product cost in the later period.In this paper,starting from the material properties,the hot compression test was carried out to test the mechanical properties of the copper chromium alloy used in H continuous casting mould copper chromium alloy by Gleeble test machine.The flow stress model of the chromium copper alloy was obtained by fitting the experimental data.Secondly,the hot backward extrusion process parameters of H continuous casting mould copper tube are determined,and the thermal backward extrusion simulation model is established under the Deform software environment.By analyzing the velocity-travel,stress-travel and the metal flow line in the process,the metal flow law in the process of hot backward extrusion is revealed.Then the optimal parameters of the punch are determined,which provides a theoretical basis for reducing or eliminating the blank of the workpiece in the initial stage of the thermal backward extrusion,improving the mechanical properties of the forming workpiece and the service life of the die.Finally,the influence of different punch shapes and blank sizes on the metal flow during hot backward extrusion is studied.In order to reduce the port irregularity of extrusion parts,the hot extrusion process of continuous casting mould copper tube for H steel was optimized by means of simulation and experiment.Establish the best process flow and blank structure.