A new process including upsetting, backward extrusion of cupshaped, forward extrusion with piercing , reaming and sizing was proposed for axle sleeve that has multiple inner steps and high precision requirements, and the process had been used in real production. Furthermore, the reasons of defects, such as under filling of fillet, the situation that the web could not be completely pierced and the crack appeared at the bottom during in the development of this novel process were analyzed. The corresponding solutions were put forward as follows. The fillet was fully filled by increasing 2 mm in length at the top of part. By using FEM the web could be completely pierced by improving press load of backward extrusion process. The crack defect location was founded by setting tracking points in the numerical simulation; therefore, the crack defect was completely resolved.
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