Tube Sinking and Expanding

Abstract

In the operations of tube forming, the purpose is to change the diameter of the tube. To achieve this, the tube is drawn through a conical die (tube sinking) to decrease its diameter, or over a conical mandrel (expanding) to increase its diameter. This process is quite similar to the process of wire drawing. The analysis of this paper is an extension of a previous study of wire drawing and extrusion. An upper-bound approach to the energy consumption is utilized. The required operation stresses are computed. The maximum possible reduction in area, or maximum diametrical ratio are determined, and the optimal cone angle which will minimize the required stresses and maximize the reduction possible is evaluated.