| Profile rolling of seamless rings constitutes an efficient manufacturing process offering excellent material yield, energy conservation, and component production, which require a minimum of subsequent machining operations. The main objective of this investigation is to develop an analysis technique for modeling profile ring rolling. This technique provides a new design paradigm for an industry relying heavily on designer experience and cut-and-try methods. As a rapid simulation tool to aid designers in developing ring-rolling process schedules, thereby helping in reducing the design and analysis cycle time, the potential to capture the unique 3-D flow situation experienced in shape rolling of seamless rings is being explored. In this research, Upper Bound Elemental Technique (UBET) with linear velocity fields that can satisfy the kinematically admissible boundary conditions, are being proposed to model the deforming body between the roll-gap in order to reduce the execution time taken for a simulation. Since the bulk of the deformation is taken place at the roll gap while the remainder of the ring is in rigid body motion, the concentration of the analysis to the material at roll gas has not introduced a significant inaccuracy between the model and the actual deformation. Due to this focus analysis of UBET on deformation, simulations can produce acceptable results while considerably reducing the execution time.; In order to validate the UBET model, SMS Wagner-Banning Rolltech simulation tool, which is a widely used controlled simulation tool in ring rolling industry, has been used. Rolltech is based on both experimental data and analytical models limited to rectangular cross sections. Comparison of simulation results with Rolltech data has reveled that the UBET tool can produce ring dimensions, roll separation force, and temperature at an acceptable accuracy. Further comparisons of the complex ring profiles with actual flow data has shown that the simulations have produced die fill and roll force, which would observe in actual practice. |
