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Selection of common roll material

1. Selection of work roll material

Front roughing work roll (R1) : The front roughing work roll must be of strong toughness, wear resistance and heat crack resistance. The hardness ranges from HS40 to 55. Generally, roll made of 60CrNiMo cast steel is selected.

After roughing work roll (R2) : After roughing work roll requires the use of a material with good crack resistance. Semi - steel, high - chromium steel, high - speed steel material.

Front work roll for finishing (F1-4) : High temperature and heavy load of front work roll for finishing. Casting semi - steel and high - chromium centrifugal cast iron and other materials are generally selected. The high chromium centrifugal cast iron has higher wear resistance and heat crack resistance on the roll surface, and can suppress the spot and blemish on the roll surface.

After finishing roll (F5-7) : After finishing roll is used in the final stage of rolling and has a very important influence on product quality and surface condition. Roll performance is mainly high hardness, wear resistance, indentation, spalling resistance and heat crack resistance, the general selection of unlimited cold cast iron (ordinary, improved) and other materials.

2. Selection of supporting roller and vertical roller materials

Both rough and finishing supporting rolls require good thermal cracking resistance, wear resistance, fatigue resistance and high strength. In terms of material, composite cast steel, alloy forged steel (Cr3, Cr5) and other materials are generally selected.