roughness-width cutoff[′rəf·nəs ¦width ′kəd‚ȯf]
in metalworking, the surface layer of billets or semifinished products that is to be removed in subsequent treatment. This cutoff allowance is necessary because of imprecision in the shape and size of the billets, high surface roughness, and because of various defects of the surface, such as a decarbonized top layer and scale.
The roughness-width cutoff value depends on how the billet is produced—that is, whether it is cast, stamped, or rolled—and on how it is to be further treated. Reducing this value is one of the most important goals in metalworking, since such a reduction leads to savings in materials and to a decrease in the labor intensiveness and cost of subsequent treatment.