S. G. Iron rolls are so superior in wear resistance to that of cast steel rolls that they are specially adapted for roughing and intermediate plate mills and rod or bar mill roughers. As a result of the spheroidal form of the graphite, s g iron rolls are much stronger than rolls of the clear-chill type and the gradual fall in hardness is an added advantage, as such, these rolls are particularly suitable for skelp and strip mills, also bar billet mills, and are being increasingly used for other applications.