Design of roll profile in shape rolling of an irregular angle bar by the modified butterfly method

The roll profile of an angle bar is generally designed by the butterfly method however, the design of the roll profile of an irregular angle bar requires a special rule to take a tapered leg or a protrusion on the leg into account. For this purpose, the butterfly method has been modified in this study to design the roll profile for an irregular angle bar by introducing the equivalent leg thickness. The thickness of the tapered leg or the leg with the protrusion is changed into the equivalent leg thickness to calculate the thickness and length of the leg for the next pass. Shape rolling processes for inverted and unequal angle bars are designed by the proposed method, and its effectiveness is verified by FE-simulation and experiments using plasticine. In addition, the design method is applied to the shape rolling of more complicated irregular angle bar, such as an automotive door hinge. The cross-sectional shapes at each pass are compared with those obtained from the experiment using steel. The results of FE-simulation and experiment show that the proposed design method effectively designs the roll profile for an irregular angle bar, leading to accurate shape and dimensions in the final product within the allowable tolerance of ± 0.4 mm in thickness and ± 1.5 mm in length. Therefore, the proposed design method can be widely used to design roll profiles for variously shaped angle bars in industrial fields.

[1]  Taylan Altan,et al.  Metal Forming : Fundamentals and Applications , 1983 .

[2]  Akio Segawa,et al.  Rolling-deformation characteristics of clad materials determined by model experiment and numerical simulation: experimental rolling tests using plasticine , 1995 .

[3]  Andrzej Milenin,et al.  Numerical modelling of the metal flow and stock bending during the rolling of unequal angle bar , 2006 .

[4]  H. Riegger,et al.  Roll pass design by interactive graphic computing , 1985 .

[5]  W. Robson.  British Steel Corporation , 1973 .

[6]  Hyungjun Kim,et al.  A new free surface scheme for analysis of plastic deformation in shape rolling , 2000 .

[7]  Zygmunt Wusatowski,et al.  Fundamentals of rolling , 1969 .

[8]  Youngseog Lee,et al.  Prediction Model of the Exit Cross Sectional Shape in Round-Oval-Round Pass Rolling , 2001 .

[9]  Junji Kihara,et al.  Roll pass evaluation for hot shape rolling processes , 1991 .

[10]  Kazutake Komori.  Simulation of Deformation and Temperature in Multipass Three-Roll Rolling. , 1996 .

[11]  Youngseog Lee.  Effect of Rolling Speed on the Exit Cross Sectional Shape in Rod Rolling Process , 2007 .

[12]  Willibald Trinks,et al.  Roll pass design , 1930 .

[13]  Naksoo Kim,et al.  A study of the rolling of I-section beams , 1994 .

[14]  Hamid Reza Koofigar,et al.  Unified gauge-tension control in cold rolling mills: A robust regulation technique , 2011 .

[15]  Zygmunt Wusatowski,et al.  CHAPTER 3 – FUNDAMENTALS OF ROLLING PROCESSES , 1969 .

[16]  S. I. Oh,et al.  Application of Three Dimensional Finite Element Analysis to Shape Rolling Processes , 1990 .

[17]  Andrzej Milenin,et al.  Simulation of metal forming during multi-pass rolling of shape bars , 2004 .

[18]  Kazutake Komori,et al.  Simulation of deformation and temperature in multi-pass caliber rolling , 1997 .

[19]  Kazutake Komori.  Simulation of deformation and temperature in multi-pass three-roll rolling , 1999 .

[20]  The mathematical modelling of thermo-mechanical processing of steel during multi-pass shape rolling , 2005 .

[21]  Yong-Taek Im,et al.  Three-dimensional finite element analysis of non-isothermal shape rolling , 2002 .

[22]  Kozo Osakada,et al.  Finite element simulation of three‐dimensional deformation in shape rolling , 1990 .