Analysis and prediction of fishtail during V-H hot rolling process

Abstract

The fishtail in head and tail of the slabs was studied during V-H hot rolling process. With the application of ANSYS/LS-DYNA, simulation analysis was used to research this process. The various factors which have a great influence on fishtail shapes were analysed, such as initial width, initial thickness, radius of the edger roll and horizontal roll, edging draught, horizontal reduction rate, and friction coefficient of the surface. Then the curves that can describe the shapes were obtained. After a certain time of self-learning, the optimized curves were given out. At last, through the fitting of the simulation test results, the math models for the area of fishtail defect changing with the presented factors were received. The experimental results show that the accuracy of the prediction for the fishtail shapes is more than 95%. With the application of the prediction for the fishtail shapes and the area of the fishtail defect, the loss rate of the slab is decreased by about 0.1%.

Keywords

fishtail / finite element / defect area / mathematical modeling

References

[1] XiongS-w, LiuX-h, WangG-d, ZhangQiang. Slab edging draught technology in roughing trains of hot strip mills and methods for improvement crop loss [J]. Iron and Steel, 1994, 29(12): 75-79

[2] KobayashicSMetal forming and the finite-element method [J], 1989, Oxford, Oxford University Press: 83-85

[3] NikaidoH. Development of slab sizing press for heavy width reduction in hot strip mills [J]. ISIJ, 1992, 17(4): 412-417

[4] OkadoM. Newlight on behavior of width of edge of head and tail of slabs in hot strip rolling mills [J]. ISIJ, 1981, 67(15): 2516-2525

[5] AnjamiN, BastiA. Investigation of rolls size effects on hot ring rolling process by coupled thermo-mechanical 3D-FEA [J]. Journal of Materials Processing Technology, 2010, 210(10): 1364-137

[6] JahangardyY, ForouzanM R, RostamipourM, DolatabadiA S. Determining structural defects in hot strip rolling mills by analyzing rolling force fluctuations [J]. Steel Research International, 2012, 29(4): 107-110

[7] ChenS W, LiuH M, PengY, SunJ L. Strip layer method for simulation of the three-dimensional deformations of large cylindrical shell rolling [J]. International Journal of Mechanical Sciences, 2013, 77: 113-120

[8] ZhangS-h, ZhaoD-w, WangX-nan. Influence of yield-to-tensile strength ratio (YT) on failure assessment of defect-free and corroded X70 steel pipeline [J]. Journal of Central South University, 2014, 21(2): 460-465

[9] LiuW-b, KangY-l, CuiL-kai. Parameter optimization of short stroke control model on 2250 hot strip mill of Qian’an steel company [J]. Steel Rolling, 2010, 27(1): 51-54

[10] LucaG, ElisabettaC, ClaudioG. Investigation of the fishtail defect in ring rolling by a FEM approach [C]. 40th Annual North American Manufacturing Research Conference, 2012, South Bend, NAMRC40: 104-111

[11] DuX-z, YangQ, LuCheng. Optimization of short stroke control curve in hot strip mill by FEM modeling [J]. Advanced Materials Research, 2010, 83/84/85/86: 106-112

[12] HeoS-c, SeoY-h, KuT-w, KangB-soo. A study on thick plate forming using flexible forming process and its application to a simply curved plate [J]. The International Journal of Advanced Manufacturing Technology, 2010, 51(1/2/3/4): 103-115

[13] TanS-b, LiL, LiuJ-chang. Research on the gap setting model of short stroke control system in hot edge rolling [C]. Chinese Control and Decision Conference, 20114126-4128

[14] ForouzanM D R, SalehiI, Adibi-SedehA H. A comparative study of slab deformation under heavy width reduction by sizing press and vertical rolling using FE analysis [J]. Journal of Materials Processing Technology, 2009728-736

[15] ZhaoD-w, FangQ, LiC-ming. Derivation of plastic specific work rate for equal area yield criterion and its application to rolling [J]. Journal of Iron and Steel Research, International, 2010, 17(4): 34-28

[16] RenR, ZhangX-p, DuX-zhong. FEM simulation of the slab edge rolling in unsteady rolling stage [J]. Applied Mechanics and Materials, 2012, 152/153/154: 297-300

[17] LiuH-q, ZhangF, YinS, LiXin. Study and application of ssc model on hot rolling wide strip mill [J]. Advanced Materials Research, 2012, 572: 131-136

[18] DuX-z, YangQ, LuCheng. Optimization of short stroke control preset for automatic width control of hot rolling mill [J]. Journal of Iron and Steel Research International, 2010, 17(6): 16-20

[19] MeiR-b, LiC-s, LiuX-hua. Heat transfer coefficient prediction by FEM in the hot strip rolling [J]. Advanced Materials Research, 2012, 415/416/417: 1391-1394

[20] WangW, LiuX J, LiuK. FEM analysis on multibody interaction process in three body friction geometry with rough surface [J]. Tribology, 2012, 6(2): 59-66

[21] YuanG-m, WangJ, XiaoH, LiM-lei. Research on online model of vertical rolling force in hot strip roughing trains [J]. Advanced Materials Research, 2011, 145: 198-203

[22] VimalanathanS, MearsL, LiC-ming. Finite element simulation of ring rolling process [J]. SAE International, 2010, 1: 270-280