Effect of roll-groove profile on tube deformation in single-stand mandrel rolling

摘要

The effect of the roll-groove profile on the cross-sectional shape of the tube at the exit of the roll-bite and on the distribution of pressure acting on the tube surface was investigated through rolling experiments with a single-stand model mill and calculations using the rigid-plastic FEM. The roll-groove profile was evaluated with the D{sub}R -θdiagram, where D{sub}R=(R -R{sub}G)/R{sub}G andθis the angle from the groove center, R is the distance from the pass center to the roll surface atθand R{sub}G is the distance from the pass center to the groove center. The results are as follows. (1) When D{sub}R at the roll flange is small, the flange diameter and peripheral length along the inner surface of the tube decrease and thickness at the tube flange increases. (2) Elongation mainly depends on D{sub}R at the groove center. (3) When D{sub}R at the roll flange is small, the pressure acting on the tube surface contacting with the roll flange increases.