Analysis of Stresses in Bar Cropping
Expansion of the use of metal forming operations has resulted in an increasing demand for high quality billets. Cropping, because of the lower material wastage, compared with traditional machining operations, can result in much reduced costs for billet production. An understanding of the mechanics of cropping is therefore of primary interest. Analysis of the process is complicated by its unstable nature, with boundary conditions and internal stresses progressively changing until fracture occurs. However, a number of attempts have been made to analyse the stresses which warrant consideration.
The present paper examines critically some of these analytical attempts with the aim of assessing their practical usefulness and contribution to the overall understanding of the cropping process0.
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