High Speed Steel Rolls (HSS)
HSS rolls have high hardness and good wear resistance at high temperature. These rolls are manufactured by Centrifugal Casting(CC) method and the roll core is filled with spheroidal graphite cast iron.The adequate chemical composition control and proper heat treatment ensures the hardness of roll working layer to reach as high as 80-85HSC. Uniformly distributed complex carbides of Vanadium,Tungsten,Niobium and Molybdenum in the martensitic matrix ensures uniform hardness of working layer and uniform wear out in the roll passes.These types of rolls are used for finishing stands to increase productivity and improve surface quality of rolled piece.
Table.1 Chemical Composition %
Table.2 Prosperities & Application
|HSS||30-45||75-95||￠300~700||800`15000||Finishing work rolls for hot strip mills and bar mills;|
|S-HSS||30-45||75-98||Roughing work rolls for hot strip mills; work rolls and intermediate rolls for cold strip mills|