Rolled Rings

Ring rolling is a specialised type of hot rolling that increases the diameter of a ring.  The starting material is a thick-walled ring. This piece is placed on an idler roll, while another roll presses the ring from the outside.  As rolling occurs the wall thickness decreases as the diameter increases.  The rings may be shaped to form various cross-sectional shapes.  The resulting grain flow is circumferential, which gives better mechanical properties.