Key Technology Research Of Multi-layer Stepping Aluminum Wheel Continuous Heat Treatment Production Line

Multi-layer stepping aluminum wheel continuous heat treatment production line has become an advanced emerging equipment in the aluminum wheel industry due to its beautiful design,high furnace temperature uniformity,low consumption and high efficiency,and high intelligence,and will have a good development trend.However,there is still a large room of the study for improvement in the temperature uniformity of its solid solution furnace,and the quenching deformation control of the workpiece.Therefore,it is necessary to conduct research on the key technology of the heat treatment production line.With the support of the National Intelligent Manufacturing Project,this paper analyzed the flow field and temperature field of the solid solution furnace,the stress-strain curve of the workpiece during quenching,and the flow field of the quenching tank by using numerical simulation.Based on the simulation results,optimization schemes were proposed to guide the actual design.Aiming at the problems that the temperature uniformity of multi-layer super-large furnace is difficult to guarantee,numerical simulation was used to research the hot-air circulation system of solid solution furnace,and two optimization schemes were proposed.By analyzing the flow field and temperature field simulation results of two optimization schemes,a better optimization scheme was selected.The shape,size and other influencing factors of the deflector of the optimization scheme were further optimized.and the finally optimization scheme results to show:one inlet and one arc plate were added to the draft plate near the second and third layer wheels respectively,and when the two circular arc baffles were respectively 100 mm and 150 mm,the flow field in the furnace was compared uniform,and the uniformity of temperature of each layer of the heating zone was better.Based on the above research,different circulating air volume parameters were selected,and the effect of each circulating air volume on the flow field and temperature field of the solid solution furnace was analyzed by numerical simulation.The results show that:considering the process requirements,safety,economy and other factors,the relatively better circulating flow is designed in such a way that two fans were used at the near furnace door area of the furnace,the integrated air volume were 90000 m~3/h,and the central part of the furnace is single、large fan,the air volume was 72000 m~3/h.Finally,The rationality of the scheme was verified by experiments.Finally,the design of the hot air circulation system was guided,and the requirement of furnace temperature uniformity±3℃was achieved.Aiming at large stress and deformation of the workpiece in conventional quenching tank,numerical simulation was used to research the circulation system of quenching tank.The temperature and stress/strain coupling model of the workpiece during quenching of the initial design quenching tank is simulated and analyzed,and the workpiece temperature and stress/strain curves were obtained.The optimization scheme of the quenching tank was based on the quenching medium stirring intensity and flow field uniformity.the design of the number of nozzles,side nozzle angle,nozzle height,nozzle flow rate and other factors were further optimized based on the above research.The final design of the quenching tank was to increase the nozzle both at the bottom and side of the workpiece,when the number of side nozzle was 25,the nozzle inclination angle is 45°,the nozzle flow rate is 7m/s,the groups number of bottom nozzle was 5,the nozzle is 30°to the wheel center line,and the nozzle flow rate is 3m/s,which can not only ensure the abundance of the quenching medium,but also ensure the uniform flow field in the effective quenching zone.The rationality of the scheme was verified by experiments.Finally,the design of the quenching tank circulation system was guided.After inspection,the workpiece processed by the heat treatment production line realized less distortion,and the mechanical properties and microstructure properties meet the design requirements.