Abstract
The article presents the results of a study of the process of double-support plastic bending of rod blanks of round cross-section. The process of deformation of a round workpiece, which was located on two fixed supports, and was deformed by a punch with a cylindrical working surface, was considered. The punch was located in the middle between the supports and moved perpendicular to the longitudinal axis of the original undeformed workpiece. Based on the analysis of the geometric parameters of the double support bending process, the dependence of the displacement h of the working tool on the bending angle α was established. To generalize the results obtained and the possibility of their use in a wide range of workpiece and tool sizes, dimensionless parameters were introduced and the dependence of the relative movement of the punch on the bending angle was obtained. Using the finite element method (DEFORM-3D software package), a computer simulation of the process of two-support bending of round rod blanks was performed. When modeling the bending process, grade 40C2A steel, which is used in the manufacture of spring terminals for rail fastenings, was considered as the material of the bent workpiece. The hardening curve used in the calculations was constructed based on the results of tensile tests. Based on the modeling results, patterns of changes in the deformation force and cross-sectional shape at various stages of deformation were established. Experimental studies of the double-support bending process were carried out on an IR 5082-100 testing machine. The discrepancy between theoretical and experimental data will not exceed 5-7%.
Keywords:
plastic bending, rod blank, double-support bending, bending angle, tool stroke, finite element method, deformation force, deformation force, stress state