The Study Of Forming Parameters And Defects Control During The Synchronous Rotation Mode Ring Spinning Deformation Of Long Cylinders

Cylinders played a important role in aerospace, weapons, aviation and other fields. Traditional power spinning could not complete the overall spinning of long cylinders, the reasons was that welding segment easily lead welding deformation and localized necking. Due to the weight of long cylinders was large and only applied feed ratio at one end of the long cylinders, easily leading aroused bending deformation which could not achieve roundness, straightness, diameter precision.Against the diadvantages of traditional power spinning above, the synchronous rotary die ring spinning were adopted. Unlike the traditional spinning, the spinning applied force and auto-rotate at both ends, that was axial thrust and adaptive axial tensionin, completed the processing of the workpiece in the process of moving and rotating. By this means used very short length annular core mold (between 300-500mm in length) to complete the long cylinders overall spinning that was large-diameter, high-precision, long barrel (beyond 8m). At the same time, the spinning relied on tension to ensure the roundness and straightness, which is fare higher than traditional spinning.Based on finite element numerical simulation software Simufact, the key issues such as meshing, boundary condition and geometry model building were analyzed, the model was assumed and simplified. The Elastie-Plastic finite element theory interrelated to spinning proeess was explained, including incremental equations, virtual work equation, finite element method equation.The distribution of effective stress-strain, materials flow, the distribution of three-spinning force and defects in forming process such as wrinkling, drum-shaped, expanded diameter was investigated. The forces of the ring mold and the effects of different process parameters on the forming process were analyzed, the range of the main process parameters were determined, such as the length of the mandrel, the feed ratio, radius, angle forming.Combined the orthogonal experiment and numerical simulation, the process parameters were optimized, aiming at minimum axial spin stress and the wall thickness difference, the effections of different process parameters on synchronous rotary die ring spinning were analyzed. The optimized forming processing parameters and the order of the parameters that affect primarily and secondarily on parameters were obtained, which provides the theoretical basis for the synchronous rotary die ring spinning forming process and parameter optimization.