Numerical Simulation Research On Continuous Drive Friction Welding Process Of Small Sleeve Of Blast Furnace Tuyere

The small sleeve of blast furnace tuyere is the key equipment of the iron making blast furnace air inlet system,which is manufactured by T2 copper processing.It is an important device to ensure the normal production of iron making blast furnace.There are defects such as sand inclusion in the overall casting process of the tuyere sleeve,which cannot meet the requirements for use.At present,MIG automatic welding is mostly used,with many welding defects and high scrap rate.Therefore,continuously drive friction welding is used to weld the small sleeve of blast furnace tuyere.When the small sleeve of blast furnace tuyere is welded by continuous drive friction welding process,there is no need to clean the surface of the welding workpiece in advance.The production difficulty is reduced and the welding defects in the welding process are reduced.The scrap rate of small sleeve of blast furnace tuyere is reduced,which is of great significance for enterprises to obtain good welding joint and reduce production cost.Firstly,based on the basic theory of heat transfer and elastic-plastic theory of T2 copper,the thermodynamic analytical model and temperature field mathematical model of continuous drive friction welding for small sleeve of blast furnace tuyere are established.The two-dimensional geometric model and material model of small sleeve of blast furnace tuyere are established in DEFORM software.The material model is the T2 copper Johnson-Cook material model,which also considers the change of the material's thermal properties with temperature.The contact and boundary condition settings and meshing of the geometric model were carried out.Secondly,the transition time of friction state in the process of continuous drive friction welding of blast furnace tuyere is analyzed.The space and time distribution of temperature field and the simulation results of stress field and strain field in the welding process are analyzed.The results show that the temperature of tuyere small sleeve of blast furnace increases continuously in the initial stage of welding.After the loading is stable,the temperature of tuyere small sleeve of blast furnace is stable at about 850?,and the temperature begins to decrease gradually after entering the upsetting stage.The equivalent stress at the beginning of the blast furnace tuyere was relatively evenly distributed.As the welding process progressed,the equivalent stress gradually showed a difference,and a large stress concentration area appeared.The stress concentration area gradually expands,and then the equivalent stress distribution tends to stabilize.Entering the upsetting stage,the equivalent stress first increases sharply,then gradually decreases to zero.Then,in view of the important process parameters such as rotation speed,friction pressure and upset pressure,the established models of continuous drive friction welding for small sleeve of blast furnace tuyere are simulated and analyzed.The effects of these process parameters on the flash appearance,maximum temperature,axial shortening and torque of small sleeve of blast furnace tuyere were studied.The results show that with the increase of these process parameters,the flash,maximum temperature,axial shortening and torque formed during the continuous drive friction welding of the small sleeve of blast furnace tuyere are gradually increased,and the time for the torque increase is gradually advanced.When the process parameters are too large,it will affect the appearance and welding quality of the welded joint,which will increase the difficulty of later joint processing.Finally,combined with the basic theory of fluid solid coupling in continuous drive friction welding,the three-dimensional model of continuous drive friction welding for small sleeve of blast furnace tuyere is established.The mesh generation and related parameters were set in fluent software,and the flow velocity of the material on the welding interface was analyzed.The results show that:with the welding process going on,the flow velocity of material on the welding interface of small sleeve of blast furnace tuyere increases gradually.The flow velocity and flow range reach the maximum value at 8 seconds,and then decrease gradually.