A Unified Velocity Field for Analysis of Flat Rolling Process

Amjadian, P.; Haghighat, H.

doi:10.22060/mej.2017.12585.5374

A Unified Velocity Field for Analysis of Flat Rolling Process

Document Type : Research Article

Authors

Mechanical Engineering Department, Razi University, Kermanshah, Iran

10.22060/mej.2017.12585.5374

Abstract

The subject of this paper is analysis of the flat rolling process by upper bound method.
In this analysis the arc of contact has been replaced by a chord and the inlet and outlet shear boundaries
of the deformation zone have been assumed as arbitrarily exponential curves. A unified kinematically
admissible velocity field has been proposed that permits the possible formation of internal defects. By
minimizing the required total power with respect to the neutral point position and the shape of the inlet
and outlet shear boundaries, the rolling torque has been determined. The velocity components obtained
from the upper bound method have been compared with the FE simulation. The analytical results have
been showed a good agreement between the upper bound data and the FE results. A criterion has been
presented to predict the occurrence of the split ends and central bursts defects during flat rolling process.
Comparison of analytically developed approach for rolling torque and internal defects with published
theoretical and experimental data have been showed a good agreement. Finally, the effects of process
parameters on the safe and unsafe zones sizes have been investigated. It is shown that with increasing of
the friction factor, the safe zone size is decreased.

Highlights

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Keywords

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