Abstract: Error estimation, double mesh as well as fore-and-aft process program are applied in the rigid-viscous-plastic finite element simulation of tube unsteady extrusion. By error estimation, element can be reasonably divided. The double mesh includes analytical mesh and material mesh. The former is used in the finite element analysis, while the latter is used in the record of distortion history. The fore-and-aft process program is used in the input and output of data and computer mapping. In the results, analytical mesh, distorted material mesh and strain contours are mapped by computer.

Key words: finite element method, forming, extrusion, error estimation, double mesh.