Uneven shapes formation mechanism of heavy plate during vertical rolling

Abstract

This paper clarified the formation mechanism of the uneven shapes of a wide and heavy plate during vertical rolling (edging). Coordinate movements of material from the plate length center were constrained by both the rolled part and the to-be-rolled part during the steady edging phase. Then the higher dog-bone height and the shorter dog-bone length were formed around plate length center part, comparing to dog-bone shapes formed at plate head and plate tail. During the plate head edging phase, the main plastic deformation zone extended from the roller-plate contact zone to the plate head. Only the to-be-rolled part constrained deformation of material from the main plastic deformation zone, so it was easier for material flew into its width direction as well as its length direction than it did during the steady edging phase. Coordinate movements of the rolled material led to the width shortage around the plate head zone and increased the plate head concave shape. During the plate tail edging phase, the main plastic deformation zone extended from the roller-plate contact zone to the plate tail. Deformation constrain from the to-be rolled part disappeared gradually while that from the rolled part worked through the plate tail edging. Material of the main deformation zone flew into its width direction as well as its length direction more easily than it did during the steady edging too. Coordinate movements of the to-be rolled material increased the plate tail concave shape. The research results provided deep understanding for SSC in plate/strip edging and guidelines to develop new methods for plate/strip plan view pattern control.