A mechanical model of cold rolling of foil is coupled with a sophisticated tribological model. The tribological model treats the “mixed” lubrication regime of practical interest, in which there is “real” contact between the roll and strip as well as pressurized oil between the surfaces. The variation of oil film thickness and contact ratio in the bite is found by considering flattening of asperities on the foil and the build-up of hydrodynamic pressure through the bite. The boundary friction coefficient for the contact areas is taken from strip drawing tests under similar tribological conditions. Theoretical results confirm that roll load and forward slip decrease with increasing rolling speed due to the decrease in contact ratio and friction. The predictions of the model are verified using mill trials under industrial conditions. For both thin strip and foil, the load predicted by the model has reasonable agreement with the measurements. For rolling of foil, forward slip is overestimated. This is greatly improved if a variation of friction through the bite is considered.
Issue Section:
Technical Papers
Topics:
Film thickness,
Friction,
Lubrication,
Pressure,
Stress,
Strips,
Tribology,
Deformation,
Shapes,
Shear stress
1.
Fleck
, N. A.
, Johnson
, K. L.
, Mear
, M. E.
, and Zhang
, L. C.
, 1992
, “Cold Rolling of Foil
,” Proc. Instn. Mech. Engrs
, 206
, pp. 119
–131
.2.
Johnson, K. L., 1985, Contact Mechanics, Cambridge University Press, Cambridge, UK.
3.
Dixon, A. E., and Yuen, W. Y. D., 1995, “A Computationally Fast Method to Model Thin Strip Rolling,” Proc. Computational Techniques and Application Conference, pp. 239–246.
4.
Gratacos
, P.
, Montmittonet
, P.
, Fromholz
, P.
, and Chenot
, J. L.
, 1992
, “A Plane-Strain Elastic Finite-Element Model for Cold Rolling of Thin Strip
,” Int. J. Mech. Sci.
, 34
, pp. 195
–210
.5.
Le
, H. R.
, and Sutcliffe
, M. P. F.
, 2001
, “A Robust Model for Rolling of Thin Strip and Foil
,” Int. J. Mech. Sci.
, 43
, pp. 1405
–1419
.6.
Sutcliffe
, M. P. F.
, and Johnson
, K. L.
, 1990
, “Lubrication in Cold Strip Rolling in the “Mixed” Regime
,” Proc. Instn Mech Engrs.
, 204
, pp. 249
–261
.7.
Sheu
, S.
, and Wilson
, W. R. D.
, 1994
, “Mixed Lubrication of Strip Rolling
,” STLE Tribol. Trans.
, 37
, pp. 483
–493
.8.
Lin
, H. S.
, Marsault
, N.
, Wilson
, W. R. D.
, 1998
, “A Mixed Lubrication Model for Cold Strip Rolling: Part I—Theoretical
,” Tribol. Trans.
, 41
, pp. 317
–326
.9.
Marsault, N., Montmitonnet, P., Deneuville, P., and Gratacos, P., 1998, “A Model of Mixed Lubrication for Cold Rolling of Strip,” Proc. NUMIFORM 98, Twente University, Netherlands, A. A. Balkema (Rotterdam), pp. 715–720.
10.
Schey
, J. A.
, 1983
, “Surface Roughness Effects in Metalworking Lubrication
,” Lubr. Eng.
, 39
, pp. 376
–382
.11.
Sutcliffe
, M. P. F.
, 1988
, “Surface Asperity Deformation in Metal Forming Processes
,” Int. J. Mech. Sci.
, 30
, pp. 847
–868
.12.
Wilson
, W. R. D.
, and Sheu
, S.
, 1988
, “Real Area of Contact and Boundary Friction in Metal Forming
,” Int. J. Mech. Sci.
, 30
, pp. 475
–489
.13.
Sutcliffe
, M. P. F.
, and Johnson
, K. L.
, 1990
, “Experimental Measurements of Lubricant Film Thickness in Cold Strip Rolling
,” Proc. Instn Mech Engrs
, 204
, pp. 263
–273
.14.
Tabary
, P. E.
, Sutcliffe
, M. P. F.
, Porral
, F.
, and Deneuville
, P.
, 1996
, “Measurements of Friction in Cold Metal Rolling
,” ASME J. Tribol.
, 118
, pp. 629
–636
.15.
Le
, H. R.
, and Sutcliffe
, M. P. F.
, 2000
, “A Two-Wavelength Model of Surface Flattening in Cold-Metal Rolling With Mixed Lubrication
,” STLE Tribol. Trans.
, 43
, No. 4
, pp. 595
–602
.16.
Le
, H. R.
, and Sutcliffe
, M. P. F.
, 2001
, “A Semi-Empirical Friction Model for Cold Metal Rolling
,” STLE Tribol. Trans.
, 44
, No. 2
, pp. 284
–290
.17.
Keife
, H.
, and Ionsater
, T.
, 1997
, “Influence of Rolling Speed Upon Friction in Cold Rolling of Foils
,” ASME J. Tribol.
, 119
, pp. 349
–357
.18.
Fleck
, N. A.
, and Johnson
, K. L.
, 1987
, “Towards a New Theory of Cold Rolling Thin Foil
,” Int. J. Mech. Sci.
, 29
, pp. 507
–524
.19.
Sutcliffe, M. P. F., and Montmitonnet, P., 1999, “A Coupled Tribology and Mechanical Model for Thin Foil Rolling in the Mixed Lubrication Regime,” Proceedings of the 3rd Conference on Modeling of Metal Rolling Processes, 13–15 December, London, The Chameleon Press Ltd., pp. 187–196.
20.
Sutcliffe, M. P. F., and Montmitonnet, P., 2001, “Numerical Modeling of Lubricated Foil Rolling,” Revue de Metallurgie, pp. 435–442.
21.
Montmitonnet
, P.
, Delamare
, F.
, and Rizoulie`res
, B.
, 2000
, “Transfer Layer and Friction in Cold Metal Strip Rolling Processes
,” Wear
, 245
, No. 1–2
, pp. 125
–135
.22.
Briscoe
, B. J.
, Scruton
, B.
, and Willis
, F. R.
, 1973
, “The Shear Strength of Thin Lubricant Films
,” Proc. R. Soc. London, Ser. A
, A333
, pp. 99
–114
.23.
Bair
, S.
, and Winer
, W. O.
, 1982
, “Some Observations in High Pressure Rheology of Lubricants
,” ASME J. Lubr. Technol.
, 104
, pp. 357
–364
.24.
Evans
, C. R.
, and Johnson
, K. L.
, 1986
, “The Rheological Properties of Elastohydrodynamic Lubricants
,” Proc. Instn Mech Engrs
, 200C
, pp. 303
–312
.25.
Eyring
, H.
, 1936
, “Viscosity, Plasticity and Diffusion as Examples of Reaction Rates
,” J. Chem. Phys.
, 4
, pp. 283
–291
.26.
Sutcliffe
, M. P. F.
, 1991
, “Measurements of the Rheological Properties of a Kerosene Metal-Rolling Lubricant
,” Proc. Inst. Mech. Engrs.
, B205
, pp. 215
–219
.27.
Christensen
, H.
, 1970
, “Stochastic Models for Hydrodynamic Lubrication of Rough Surfaces
,” Proc. Instn Mech Engrs
, 104
, Pt. 1, pp. 1013
–1022
.28.
Patir
, N.
, and Cheng
, H. S.
, 1978
, “An Average Flow Model for Determining Effects of Three-Dimensional Roughness on Partial Hydrodynamic Lubrication
,” ASME J. Lubr. Technol.
, 100
, pp. 12
–17
.29.
Korzekwa
, D. A.
, 1992
, “Surface Asperity Deformation During Sheet Forming
,” Int. J. Mech. Sci.
, 34
, No. 7
, pp. 521
–539
.30.
Sutcliffe
, M. P. F.
, 1999
, “Flattening of Random Rough Surfaces in Metal Forming Processes
,” ASME J. Tribol.
, 12
, pp. 433
–440
.31.
Wilson, W. R. D., and Walowit, J. A., 1972, “An Isothermal Hydrodynamic Lubrication Theory for Strip Rolling With Front and Back Tension,” Proc. 1971 Tribology Convention, I. Mech. E., London, pp. 164–172.
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