Development of the elongation-control mill and its application to flat-wire rolling --development of elongation-control rolling I

摘要

A novel continuous tandem rolling technique, elongation-control rolling, is proposed. The aim is to control the elongation or the lateral spread of a workpiece during rolling to achieve size-free rolling, a rolling technique usable with a workpiece of any size. The elongation is controlled by interstand force, which varies widely from tensile to compressive. A prototype five-stand mill was constructed. Flat-wire rolling experiments were conducted using commercially pure round aluminum bars. Interstand forces were generated by changing the roll speed ratio of the stands. The limits of interstand force to achieve stable rolling operation were clarified. The tension limit is due to the slipping of rolls on the workpiece, while the compression limit is due to the buckling of the workpiece between stands. It has been clarified that elongation of the workpiece can be controlled to be a great degree. Compressive interstand force decreases the elongation and increases the lateral spread.