LOAD ESTIMATION FOR SHAPING A CIRCULAR TUBE INTO A SQUARE SECTION BY ROLLING

In this work, equations are derived to predict the rolling load and torque in shaping a circular tube into one with a square section by rolling based on the concept of plastic bending and unbending of the tube wall. The derived relationships are validated against experimental and numerical results. The experimental study for the shaping process by rolling is carried out using a specially designed laboratory rolling mill having 90° V-grooved rolls. The rolling load and torque are measured using a specially designed and calibrated load cells. The numerical results are obtained using finite element simulation. The rolling load and torque obtained analytically, experimentally and numerically are compared. Comparison of results shows fair agreement among the three techniques which validates the developed equations. The effect of lubrication conditions and roll opening on the rolling load and torque are also investigated.