Investigation of coil-break formation during uncoiling of fully annealed low carbon steel sheet using FE simulation
Document Type
Article
Publication Date
2-1-2021
Abstract
A 3D finite element (FE) model is developed for evaluating the formation of coil breaks during uncoiling of full-annealed low carbon steel sheets. The model consists of a 2-lap coil measuring 600 mm in inner core diameter and 300 mm in coil width with an initial sheet thickness of 1.5 mm. The forward coil tension TF is increased from 31 N/mm to 176 N/mm, and the change in true strains (LE11) and stress distributions (S11) along the longitudinal direction on the top surface of the sheets is recorded. The simulation results showed that there are six highly concentrated LE11 zones i.e. zones A (narrow bands of tensile strains or coil break) and B (islands of compressive strains) formed across the top surface of the sheet. The periodical elastic-plastic deformation is evidenced by the formation of both zones resulting from the localised plastic deformation and the incomplete unbending. The LE11 distribution is uneven across each zone. Although tensile LE11 is obtained in both the middle and edge portions of zones A, the values are compressive in the middle and tensile in the edge portions of zones B. The overall strain value of the sheets increased with increasing TF resulting in decrease in tensile LE11 peak heights in zones A and increase in strain difference between the middle and the edge portions in zones B. The degree of coil-break became more severe with increase in LE11 peak heights as demonstrated in the edge portion of zones B with increase in TF. In the sensitivity analysis using a refined mesh model for T-F = 166 N/mm, only the strain values in the edge portions of zones B increased due to the increase in amount of edge curling resulting from the transverse contraction of the sheet under the high TF. With an Anti-Coil-Break (ACB) roll, the amount of edge curling reduced and the amount of tensile LE11 in the edge portions of zones B is successfully reduced by 30%. However, ACB failed to decrease LE11 peak heights in other zones despite using higher applied load.
Keywords
Coil break, Low carbon steel sheet, Finite element simulation, Cold rolled coil, Edge break
Divisions
mechanical
Funders
Universiti Malaya (RF026A-2018)
Publication Title
Engineering Failure Analysis
Volume
120
Publisher
Pergamon-Elsevier Science Ltd
Publisher Location
THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND