Prediction of Billet Fracture at Two-High Screw Rolling Piercing

Two-high screw piercing of steel 50 billets was performed at feed angles 15 and 18 degrees. Piercing stopped 10–12 mm distance from the rear end billet. Axial fracture registered degrees angle in front mandrel nose, while no observed angle. for similar parameters simulated using DEFORM finite element analysis software, several criteria were used prediction. Ayada criterion ineffective, as evidenced by comparison with experimental data. The normalized Cockcroft–Latham effective prediction only axial zone. Results this study showed that most technique is construction a dependence “accumulated strain–stiffness coefficient tension” along trajectory point movement.