Sub roll hot-rolled and cold roll roller two.
Commonly used in cold roll work roll materials have 9Cr, 9Cr2, 9Crv, 8CrMoV and so on, cold roll quenching requirements of the surface hardness for the HS45 ~ 105.
Materials commonly used in hot-rolling roll has 55Mn2, 55Cr, 60CrMnMo, 60SiMnMo and so on, hot-rolled billet roller used in the open, thick, steel processing and so on. It to bear a powerful rolling force, dramatic effects of wear and thermal fatigue, and hot-rolled at high temperature roller job, and permit the diameter of the workload units wear, so do not require surface hardness, and wishes only to have a high strength, toughness and heat resistance. Hot Roller only the overall normalizing or quenching, the surface hardness HB190 ~ 270.