Groove defect by shelling at the roll - 1.7139
Groove defects arise from places broken off at the roll groove or a disc roll. The rolling stock presses itself in into these voids. In the further rolling course the raised material is pressed in again into the roll wire. In the microsection the defects look similar as pinchers. The defects are, however, restricted locally and recur in certain distances into longitudinal direction of the roll wire. The distances between the single defects are dependent on the size of the roll groove or the disc roll. The defects are scaled and have a decarburization this one isn't stronger than that one of the defect-free wire surface.
Rod wire 24,00 mm round - untreated