The effects of the ridge length and angle of various convex anvils on the concave shape formed at the side of a lead plate after width pressing and the bulging deformation behavior that occurs during rolling were investigated experimentally using a lead model and three-dimensional FE analysis. The control of edge-seam defects was then studied under the condition of increasing of the amount of width pressing. On the basis of the results, it is clear that the concave depth at the slab sides can

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... increased by shortening the ridge length of the convex anvils and can be controlled by adjusting the anvil angle. A rectangular shape at the sides of hot-rolled bars can be obtained by using a suitable convex shape and by subsequent bulging deformation during rolling. Therefore, edge-seam defects due to the maneuvering of wrinkles toward strip surfaces can be controlled by decreasing the amount of bulging deformation at the hot-rolled bar sides. That is, the mechanism behind the control of edge-seam defects by using convex anvils is equivalent to that of rolling a thinner rectangular slab. This technology for decreasing edge-seam defects has been applied to actual rolling equipment, and as a result, the amount of edge-seam defects has been reduced.