Rolling fins are bead-like enhancements on the surface of
the rod wire or of the steel bar. The defects go in lengthways direction. They
can arise because of wrong adjustment of the roll groove or because of roll wear.
By an overfill of the box groove, rolled piece is pushed into the roll bite. The
defect can occur one-sided, but also by 180° transposed.
25,00 mm round - untreated