Analysis of asymmetrical hot strip rolling by the slab method

  • Y. M. Hwang
  • G. Y. Tzou
Shaping and Forming

Abstract

Two analytical models based on the slab method are proposed to examine the behavior of sheet at the roll gap during the asymmetrical hot strip rolling process. In model I, the effect of shear stress in vertical plane at the roll gap is considered, whereas this effect is neglected in model II. Neutral points between rolls and strip, rolling pressure distributions along the contact art length of rolls, rolling forces, and rolling torques can be calculated easily by these proposed analytical models. The results including rolling pressure distributions, rolling forces, and rolling torques by both models are compared. The rolling pressure distribution predicted by model I shows that a “pressure well” develops in the cross shear region. On the other hand, no “pressure well” is predicted in model II. Furthermore, the rolling forces predicted by model I are always lower than those measured in the experiment, whereas those predicted by model II are always higher. However, the averages of the values predicted by model I and II are in fairly good agreement with the experimental data. Thus this analytical approach can offer useful knowledge in designing the pass schedules of the asymmetrical hot strip rolling processes.

Keywords

asymmetrical rolling cross shear region hot strip rolling slab method 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    D. Rusia, Improvements to Alexander’s Computer Model for Force and Torque Calculations in Strip Rolling Process,J. Mater. Shaping Technol., Vol 8, 1990, p 167–177Google Scholar
  2. 2.
    D. Rusia, Review and Evaluation of Different Methods for Force and Torque Calculation in the Strip Rolling Process,J. Mater. Shaping Technol., Vol 9, 1991, p 117–125Google Scholar
  3. 3.
    J.G. Lenard, Measurements of Friction in Cold Flat Rolling,J. Mater. Shaping Technol., Vol 9, 1991, p 171–180Google Scholar
  4. 4.
    R.B. Sims, The Calculation of Roll Force and Torque in Hot Rolling Mills,Proc. Inst. Mech. Eng., Vol 167, 1954, p 191Google Scholar
  5. 5.
    E. Orowan, The Calculation of Roll Pressure in Hot and Cold Flat Rolling,Proc. Inst. Mech. Eng., Vol 150, 1943, p 140Google Scholar
  6. 6.
    H. Shiozaki et al., The Property of Asymmetrical Hot Strip Rolling,Proc. of the 33rd Joint Conf. of JSTP, Japan Society for Technol. of Plasticity, 1982, p 9 (in Japanese)Google Scholar
  7. 7.
    H. Yamamoto et al., Effects of Friction Coefficients on Asymmetrical Strip Rolling,Proc. of the 34th Joint Conf. of JSTP, Japan Society for Technol. of Plasticity, 1983, p 149 (in Japanese)Google Scholar
  8. 8.
    H. Shiozaki et al., Experimental Results of Asymmetrical Strip Rolling,Proc. s-53 Sp. Conf. of JSTP, Japan Society for Technol. of Plasticity, 1978, p 33 (in Japanese)Google Scholar
  9. 9.
    K. Nakajama et al., An Investigation of Rolling Property by Rolling Experiment in Asymmetrical Strip Rolling,Proc. s-53 Sp. Conf. of JSTP, Japan Society for Technol. of Plasticity, 1978, p 25 (in Japanese)Google Scholar
  10. 10.
    H. Shiozaki et al., Effect of Rolling Speed Ratio on the Rolling Force, Rolling Torque, Forward Slip in Cold Strip Rolling,Proc. s-54 Sp. Conf. of JSTP, Japan Society for Technol. of Plasticity, 1979, p 391 (in Japanese)Google Scholar
  11. 11.
    T. Kawanami et al., The Simplified Model of Asymmetrical Hot Strip Rolling,Proc. s-57 Sp. Conf. of JSTP, Japan Society for Technol. of Plasticity, 1982, p 61 (in Japanese)Google Scholar
  12. 12.
    H. Shiozaki and M. Mikami, Theory of the Different Work Roll Speed Rolling Based on the Slip Line Field Solution for the Shearing Compression of a Flat Plate,J. JSTP, Vol 24 (No. 264), 1983, p 37Google Scholar
  13. 13.
    H. Shiozaki et al., Study on the Rolling with Different Speed Ratio,Proc. s-53 Sp. Conf. of JSTP, Japan Society for Technol. of Plasticity, 1978, p 37 (in Japanese)Google Scholar
  14. 14.
    Y.M. Hwang and G.Y. Tzou, An Analytical Approach to Asymmetrical Cold Strip Rolling by the Slab Method,J. Mater. Eng. Perform., Vol 2 (No. 4), 1993, p 597–606Google Scholar
  15. 15.
    L. Prandtle,Z. Math. Mech., Vol 3, 1923, p 401CrossRefGoogle Scholar
  16. 16.
    H. Shiozaki, Slip Line Field Solutions and Upper Bound Solutions for the Shearing Compression of a Flat Plate,J. JSTP, Vol 23 (No. 258), 1982, p 714Google Scholar

Copyright information

© ASM International 1995

Authors and Affiliations

  • Y. M. Hwang
    • 1
  • G. Y. Tzou
    • 1
  1. 1.Department of Mechanical EngineeringNational Sun Yat-Sen UniversityKaohsiungTaiwan, Republic of China

Personalised recommendations