Analysis of tube-spinning processes by the upper-bound stream-function method

Abstract

Trapezoidal and spherical velocity fields using the stream function are suggested in tube spinning. In this paper the basic mechanisms of tube spinning are explained. A search is made for the optimum roller oblique angle in terms of process parameters, such as the feed rate, the ratio of the wall thickness reduction and the friction factor. The acquired total power consumption is optimized by the Flexible Tolerance Method which is used for minimizing the multi-variable non-linear function with constraint conditions. Thus the total power consumption required in deformation and the related tangential forces are obtained using the upper-bound stream-function method. The results show that the trapezoid velocity field using the stream function provides the best agreement with the results of model-material experiment.