Numerical and experimental research of the cold upsetting-extruding of tube flanges

In this paper, the cord upsetting-extruding process of a tube flange is dis cussed in detail. Finite element method (FEM) simulation, using the program DEFORM2D, was carried out to analyze the influence of the tube dimensions and interface friction on the material flow and the cause of forming defect s. Based on the FEM simulation results, the relational curves between the f lange width and the extreme friction factors were established. The concept of a forming limit diagram for cold upsetting-extruding of a tube flange is presented. The results from the process simulation were then used in tube blank and die plan and lubricant selection. The subsequent experimental res ults showed reasonable agreement with the numerical simulation results. (C) 2001 Published by Elsevier Science B.V.