Extrusion of axi-symmetric tubes from hollow and solid circular billets:: a generalised slab method of analysis and some experiments

To analyse the mechanics of extrusion of an axi-symmetric tube starting from either a hollow or a solid circular billet, a generalised analytical approach based on the slab method of analysis is developed for a somewhat general case of tube extrusion through a general profile-shaped die and over a general profile-shaped mandrel. The results of mean extrusion pressures obtained from the theoretical analysis for the various die–mandrel combinations are compared with the experimental investigation carried out on a model material and with the work of other authors. These show reasonably good agreements.