Clear Chill Iron Rolls or better known as Definite Chill Iron Rolls have white and super-hard working surfaces, made of graphite-free cast iron. Cast iron is manufactured from eutectic carbide and austentite, which impart the quality of extra hardness and make the resultant metal alloy perfectly resistant to any kind of wear and tear.
Beneath this white iron layer, the innermost and the narrow shaft regions of the rolls are made from iron, of hard gray appearance but the iron content of the transition area between the white and gray iron layers is spotted with patches of other colors.
The white cast iron is much harder and stronger than the gray part of the chilled iron rolls; hence it is more resistant to excessive mechanical stresses and all kinds of wear out, that the surface area may need to undergo during the functioning of these rolls. The extreme compressive power of this cast iron is maintained even at very high temperatures, as it happens in case of hot rolling mills.
If a fine surface finish is required, these lownickel chilled rolls can meet the demand. Rolls for hoop and skelp mills must be chosen with particular regard for strength and hardness, primarily so the rolls will match the roughing, intermediate, and finishing stands.
Clear Chill Iron Rolls of higher alloy level are capable of functioning well in two, three or four high mills, which are manufactured from top quality ferrous and non-ferrous sheets and narrow bands or sections of these metal alloys. These Chill Iron Rolls are highly beneficial in manufacturing the well-finished stand of the rod; these are also used in light section mills and in constant hot strip mills of various sizes or of earlier designs.
The Indefinite Chilled Rolls are manufactured by casting of the iron; however their shapes and sizes are adjusted whereas the iron is in casting and molding stage, meaning once the molted iron has not totally coagulated to make the forged iron rolls.