Simulation And Experimental Study On Rolling Forming Of Large Ring

The radial-axial ring rolling is a complex forming process in which the ring rolling machine is simultaneously rolled in the radial direction and the axial direction of the annular blank,and is mainly used for rolling large ring parts.With the development of computer technology,a three-dimensional model of radial axial ring rolling is established in the computer according to the actual size of the ring rolling machine.Using finite element software to simulate the process of ring rolling to guide the actual production of large ring parts has become the development trend of modern ring rolling technology researchIn this paper,the finite element simulation and experimental research are combined to study the ultra-large ring radial-axial rolling technology with the finished product size of ?15600×?15000×670mm,and the research contents and results are as follows:In this paper,the static and dynamic conditions of the ring rolling are theoretically deduced in combination with the ring rolling theory,which provides a theoretical basis for the selection of finite element simulated rolling process parameters.Taking 316 stainless steel as the research object,the material model was constructed.Calculated the radial-axial rolling force under the set rolling conditions,and verified the feasibility of stable rolling on the equipment.The three-dimensional model of radial-axial ring rolling was established by SolidWorks three-dimensional drawing software and imported into Deform-3D finite element simulation software,establish a three-dimensional finite element model of thermal coupling of316 stainless steel ring fittings that meets the actual production.The variation laws of equivalent strain,temperature field and rolling force and energy parameters during radial-axial ring rolling were studied,and the effects of initial rolling temperature of ring billet,rotational speed of driving roll and feed speed of mandrel roll on rolling process were explored.Theresearch results are as follows:(1)The influence of the initial temperature of the blank and the feed speed of the core roller on the force energy parameters was studied by calculating the rolling force parameters.The influence of the initial temperature of the blank on the force energy parameters was studied,and the temperature of the selected ring members was calculated respectively to be 1000?,1100?,and 1200?,the calculated results under the selected parameters indicate that the lower the initial temperature of the blank,the greater the rolling force and rolling torque required,if the temperature is too low,it will exceed the rolling capacity of the ring rolling machine.Through the calculation of different feed rates of the mandrel roller,it is found that the larger the feed speed of the core roller,the greater the rolling force and rolling torque required.(2)The initial temperature of the blank has an important effect on the final ring forming effect.As the initial temperature of the blank increases,the equivalent strain of the ring is reduced,and the plastic strain of the ring becomes more uniform.The overall temperature of the ring increases with the increase of the initial temperature of the ring blank,the higher the initial temperature of the ring blank,the more uneven the temperature distribution.With the initial temperature of the blank increases,the radial maximum rolling force decreases and the rolling force fluctuation amplitude decreases.(3)With the angular velocity of the drive roller increases,the difference between the internal and external equivalent strain of the ring increases,and the equivalent strain distribution becomes more uneven.The greater the angular velocity of the drive roller,the more uniform the temperature distribution of the ring.With the angular velocity of the drive roller increases,the maximum rolling force experienced by the ring member decreases.(4)With the feed speed of the mandrel roller increases,the feed per revolution of the ring increases,the deformation zone penetrates the ring better,and the equivalent strain distribution of the ring is more uniform.With the feed speed of the mandrel roller increases,the heat is generated faster and is not easily transmitted to the surroundings,and the overall temperature of the ring member is increased.The greater the feed speed of the mandrel roller,the greaterthe rolling force of the mandrel roller and the lower the fluctuation of the rolling force.(5)An experimental study was carried out on a ring whose diameter was reduced to a ratio of 3:1.After rolling,the microstructure was observed to be austenite,and the grains were recrystallized after rolling.Tensile mechanical properties and impact toughness at room temperature can meet national standards and enterprise requirements.