Effects of mandrel structure on ring rolling process for large-scale T-sectioned ring with numerical simulation

The process parameters including the mandrel structure of radial-axial ring rolling is in close relationship with the forming defects such as over-high axial spread and the folding defect in the connecting part of the big and small ring. In this paper, a 3D rigid-plastic and coupled thermal-mechanical finite-element model (FEM) of radial-axial ring rolling for large-scale T-sectioned ring was developed using commercial software of DEFORM-3D. By changing the chamfer radius of mandrel's work roll, the effects of mandrel structure on the height of axial spread which considerably affects the stability of the ring rolling process were investigated. The folding defect was also simulated. The numerical simulation results showed that with the decrement of the chamfer radius r, the metal increasingly accumulated in the big ring and the axial spread height increased. Consequently, the ring rolling process became unstable. Also, the folding angle augmented.