Numerical and experimental investigation on the influence of main motor rotational frequency in fine-cropping

The bar fine-cropping, the first and one of the most important metal-forming procedure, separates the work-piece into accurate products and billets. The aim of this article is to investigate the influence of different main motor rotational frequencies on a new fine-cropping system. Five different rotational frequencies are applied to both the numerical simulations and the fine-cropping experiments. The numerical and experimental results show that good agreement is achieved by combining the average stress triaxiality under different stress states: the equivalent plastic strain, the fatigue-crack propagation path analysis and the micrograph fractography observation. Additionally, the cross-section quality of cropped billets and the final cropping time is also investigated. The results show that the cross-section quality and the final cropping time of the new fine-cropping are greatly influenced by the main motor rotational frequency, especially the frequency close to 33Hz.