Bowing of Cold-rolled Strips by Multi-slitting

The relation between the cross sectional configurations of cold-rolled thin strips and the diameters of bowed strips after slitting has been investigated. When a cold-rolled strip is multi-slitted, an edge-rippled of a center-buckled strip will bow in its plane by the widthwise variation both in elastic strain and in plastic strain. The diameters of bowing due to both effects can be calculated by the equations (6), (11) in edge-rippled strips, and (10), (12) in center-buckeld strips respectively. These results have been ascertained by the slitting experiment of some cold-rolled strips

Curling of Cold-rolled Strips

The effect of cold rolling conditions upon residual stress of strip and diameter of curled coils have been investigated. If tension is relieved after rolling, cold-rolled thin strips will curl to the upper work-roll side, when the upper work-roll has a slight offset to the rolling direction from the line of centers of the lower work-roll and two back-up rolls, when the upper work roll is a little smaller in diameter than the lower-roll, and when the passline of the strips leans to the upper roll side at the exit. These results, obtained from calculations based on the residual stress distribution reported by Baker, Ricksecker and Baldwin, have been proved by the rolling experiment using a Sendzimir 20-high mill