Abstract
Since silicon steel is used in a laminated form, thickness profile in the width and the rolling directions should be accurately controlled. It is well known that the phenomenon of edge drop is one of very serious problems in cold rolling of silicon steel. In order to determine one of the better methods for reducing edge drop, a computer simulation was carried out in this study under various rolling conditions. It was found that the better way to reduce edge drop was to use a tapered work roll. A table was given for the optimal taper crown depending upon the diameter of work roll and the width of strip. The optimal condition was applied for actual cold rolling of silicon steel. As a result, edge drop was significantly alleviated.
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Abbreviations
- A ij :
-
Influence coefficient due to bending [Fig. 5]
- B :
-
Width of strip [Fig. 12]
- c :
-
Friction coefficient between WR (work roll) and BUR (back-up roll)
- D ij :
-
Flattening at center of the ith element when unit load is applied at center of the jth element [equation (13), Fig. 5]
- d(i) :
-
Flattening between WR and strip at the ith element [Eq.(12)]
- E :
-
Young's modulus of roll
- E w :
-
Young's modulus of WR [Eq. (13)]
- i, j :
-
Element index [Fig. 4]
- K s :
-
Spring constant between WR and BUR [equation (11)]
- L bw :
-
Relative rigid displacement between WR and BUR [Eq. (5)]
- ld :
-
Contact length between WR and strip [Eq. (13)]
- N :
-
Number of elements [Fig. 4]
- P i :
-
Rolling force between WR and strip at the ith element [Eq. (1), Fig. 4]
- Q i :
-
Contact pressure between WR and BUR at the ith element [Eq.(1), Fig. 4]
- P b :
-
Reaction force in the y-direction at BUR bearing [Eq. (3), Fig. 4]
- R b :
-
Reaction force in the z-direction at BUR bearing [Eq. (4), Fig. 4]
- R cb :
-
Crown of BUR [Eq. (11)]
- R cw :
-
Crown of WR [Eq.(11)]
- S i :
-
Contact pressure between WR and IMR of SRB (support roller bearing) at the ith element [equation (1), Fig. 4]
- Y by :
-
Deformation of BUR in the y-direction [Eq.(7)]
- Y bz :
-
Deformation of BUR in the z-direction [Eq.(8)]
- Y ws :
-
Dispacement at contact point between WR and strip
- Y wy :
-
Deformation of WR in the y-direction [Eq. (5)]
- Y wz :
-
Deformation of WR in the z-direction (Eq. (5)]
- Y bθ (i) :
-
Displacement of BUR in theθ i -direction [Eq. (10)]
- Y wθ (i) :
-
Displacement of WR in theθ i -direction [Eq. (9)]
- θ i :
-
The applied angle of contact pressureQ i [Eq. (1), Fig. 4]
- β i :
-
The applied angle of contact pressureS i [Eq. (1), Fig. 4]
- v :
-
Poisson's ratio [Eq. (11)]
- Δx :
-
Length increment in the x-direction
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Han, S.Y., Kim, J.T., Lee, Y.H. et al. Improvement on edge drop in cold rolling of silicon steel. KSME Journal 5, 108–114 (1991). https://doi.org/10.1007/BF02953609
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DOI: https://doi.org/10.1007/BF02953609