Cast iron rolls

Cold-hardened cast iron rolls

It has a high surface hardness (55-85HSD) and good core toughness, and is used for precision rolling of wire rods and sections

Ductile iron rolls

This type of roll material has a relatively high content of nickel-molybdenum alloy. Its matrix structure is composed of acicular bainite matrix, spherical graphite and carbides. The hardness increases with the increase of carbide content. The cast rolls have good impact toughness, and the resistance to hot cracking can be significantly improved after heat treatment. Meanwhile, the hardness difference within the working layer of the roller body is small, the wear resistance is high, and the toughness and strength are matched. It is mainly used in continuous rolling mills for section steel, hot rolling mills for pipes, rolling of bar and wire rods, medium rolling, pre-finishing rolling and finishing rolling mills. Moreover, its wear resistance and crack resistance are superior to those of cold-hardened cast iron, and it is often used in cold-rolled support rolls

Centrifugal composite high-chromium cast iron rolls

The outer layer is made of high-chromium cast iron (Cr11-20%) and the inner layer is made of cast steel. The wear resistance is increased by 30%, and the hardness can reach 60-95HSD. It is suitable for the rear frame of hot rolling, the pre-finishing rolling of cold rolling and the working rolls of tropical continuous rolling mills. After a domestic steel plant used this material, the roll replacement cycle was extended to 800 tons.