An approach to the optimal design of rolling passes

A technique for optimising the design of preforms and of intermediate dies in multi-stage processes, involving selection of major shape parameters by backward computation and design of detail by forward computation, previously applied to design of preforms for forging, was applied to process design in section rolling. This required another level of optimisation in which four of the most common sequences used in production of square sections were included. It was shown that a square/oval/square sequence minimised transverse variation of strain (a condition likely to minimise inhomogeneity of structure and properties and residual stress), and a draft, or general, design was produced. Comparison with a published experimental investigation of section rolling appears to confirm the results of computation.