Latest Developments of a New Technology HSS Work Roll for Later Stands (F4-F7) in Hot Strip Mill Finishing Trains

摘要

In early 1990's High speed steel rolls (HSS) were introduced for use in Hot Strip Mills (HSM). High chrome steel, high chrome iron and ICDP rolls (ICDP) were replaced by HSS gradually, because of their superior wear resistance and smooth roll surface during rolling. In the late 1990's enhanced ICDP that contains MC carbides (vanadium carbide, niobium carbide), started to be used in HSM finishing trains. Enhanced ICDP naturally has better wear resistance than conventional ICDP. Ever since higher wear resistant types have been developed however, their wear resistance has been limited to only 1.2 to 1.5 times conventional ICDP. Although HSS rolls have much higher (4 to 5 times) wear resistance, because of their inferior sticking and crack resistance properties, they are difficult to apply in later stands, especially in the final 2-3 stands. There is still high demand for a better performance roll for this application.