Analysis for Stress Prediction in Hot Rolling with Different Process Parameters by Finite Element Method

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056
Volume: 04 Issue: 03 | Mar -2017 www.irjet.net p-ISSN: 2395-0072
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Analysis for Stress Prediction in Hot Rolling with Different Process
Parameters by Finite Element Method
Bashishth Kumar Kushwaha 1, B.Moharana2
1Department of Mechanical Engineering, Roorkee Engineering & Management Technology Institute, Shamli, India
2 Department of Mechanical Engineering, DR. B.B.A Government Polytechnic, Karad, (Silvassa),India
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Abstract –In hot rolling mill process the rollersissubjected
to heating and cooling cycles with different processing
parameter. This nature of heat and processing parameter
found some cracks, wear and tear in hot roller. In this work,
the study of existing process was done to find the root cause of
the cracks in roller mills. The analysis of the rolling process
was done and results obtained in terms of equivalent stress
and effective plastic strain. It has been found that mill speed
and friction coefficient are the two major factors that
significantly affect the quality of rollingproducts. Lowervalue
of friction coefficient requires that number of mill passes be
increased. Higher value of friction coefficient increases the
sticking between rollers and the incoming metal leading to
defects in steel angle bar.
Key Words: Hot Rolling, Cold Rolling, Cracks, Coefficient of
Friction, Stress, Strain
1. INTRODUCTION
The sizing press followed by horizontal rolling is more
efficient in width reduction than deformation by a heavy
edger mill followed by horizontal rolling. The finite-element
analysis results for the deformation of a slab also show
reasonable agreement with measurements from an actual
mill test, and from physical modelling experiments [1]. The
effects of process parameters such as the cooling condition
of the work-rolls, the rolling speed, and the roll metal
interfacial heat-transfer coefficient on the temperature
distributions in the work-rolls as well as in the rollingmetal.
The comparison between the model predictions and
experimental results shows the validity of the proposed
model [2]. The rapid development of computer technology
and the improvement of general finite element analysis
software, especially with the development of parallel
computing technique, it has become possible to analyzecold
strip rolling process and calculatethestripdeformation with
3-D finite element contact model of rolls and strip [3]. The
temperature of H-beam was a downward trend in the hot
rolling process, however, local temperature display rising
trend, uneven deformation of flange lead to more complex
temperature distribution, there is certain correlation
between equivalent plastic stress and temperature
distributions, increasing of equivalent plastic stress as the
temperature increases, research results can provide
theoretical basis for rolling regulations and reference of the
production of hot rolling for H-beam[4-7]. Thevertical roller
mill 3-D model established in Pro/E is importedintoADAMS
through the data interactive software Mech/pro to analyze
its stress, and then carry out the FEA of the model loaded in
ANSYS. After Comparing with the material yield limit, the
both stresses are reasonable which will meet the demand of
design. This co-simulation method provides a reliable basis
for vertical roller mill design and can alsobeappliedtoother
mechanical system design process [8]. A coupled thermo-
mechanical finite element methodcomputationonsteel pipe
rolling process, gets the residual stress and strain change
rule in the rolling process. They analyzed the influence of
roller spacing and velocityparameterson residual stressand
strain, which provides a reliable theory basis for improving
the performance of hot rolling seamless steel pipe and the
optimization of rolling technological parameters[9].The roll
cross angle, rolling press quantity, intersection position and
rolling speed can change the size of the axial force, axial
forces may float small by the pressing ratio increases, lager
by rolling speed increases, bigger by adding more far
intersection point position, This conclusions have realistic
significance in cross rolling schedule making, and provide
basis theory reducing rolling axial force [10]. The ring can
approximately maintain its round shape at the initial rolling
period, when the process is entering the medium period,the
roundness of the ring becomes worse, and it tends to be
improved at the final rolling period. A series of ring rolling
experiments were conducted. So the reliability of the finite
element model of the vertical hot ring rolling process with
measurement and control was validated [11].Theformation
of edge defects in hot strips, resulting from slab corner
cracks generated in continuous casting. They developed a
model-based concepts for the identification of such initial
slab cracks. To accomplish this task a systematic finite
element tool Deform-3D was utilized. The numerical results
clearly pointed out the significant morphological changes of
the cracks during rollingand affordvaluableindicationsfora
deeper understanding of the underlying process details[12-
14]. A two dimensional elastic plastic model was used to
simulate the cold rolling of thick strip. They found the speed
and diameter of rolls have influence on the quality of rolling
products [15]. The mechanical properties of high strength
steel and mild steel at elevated temperatures. They found
that yield strength, tensile strength and elastic modulus of
steels at elevated temperatures decreases [16]. The
investigating the mechanism of thermal crack growth while
taking into account the complex thermal and mechanical
interactions during the rolling process. They utilized the
concepts of FEM for the estimation of rolls life, from the

perspective of thermal fatigue. Their work described the
methodology of predicting thermal fatigue crack growth
using innovative modelling techniques and they highlights
the importance to the operating conditions [17]. The
accuracy of the FE model was analysed through a dual
comparison by geometrical and by physical aspects. The
effectiveness of a new numerical subroutine was tested by a
comparison with experimental values acquired from an
industrial plant tool wear, the author characterized the
extent of the tool wear by wear depth. Twenty points were
used to measure tool wear depth with different area
reduction, forming angle, and stretching angle [18].There
was good agreement between experimental results and the
simulation in terms of wear and rolling friction under
different operating conditions. The analysis of disc-disc
interaction has been presented by using FEM technique.
However this work gives rise to thoughts about possible
applications in various fields [19]. The finite element model
for the prediction of the steady-state thermo-mechanical
behaviour of the roll-strip system and of roll life in hot strip
rolling. The model was comprised of basic finite-element
models, which are incorporated into an iterative-solution
procedure to deal with the interdependence between the
thermo-mechanical behavior of the strip and that of the
work roll. However, the model addressed only a part of roll
wear–related problems, leaving the rest for future works
[20]. They used finite element analysis technique to
investigate behavior of rolls related to bending, shifting and
levelling. The effective utilization of these methods, leads
improvisation of the flatness in the cold rolled sheet. Apart
from the profile of sheet, the shape was also significantly
affected by the vibrations developed in mill housing [21].
The developed procedure for the simulation of the hot
rolling process. They stated that rolling is a 3D process but
using the generalized plane strain method, the real 3D
problem can be solved using a 2D Finite Element Model,
saving an important computing time [22]. FEM software are
able to describe the kinetics of recrystallization during the
process, taking into consideration grain size refinementand
grain growth. By incorporating suchmathematical models,it
is possible to predict the formation process as a whole,
including the final microstructure obtained for the forged
part, allowing process optimization that focusesona higher-
quality final product [23]. They developed a computer
system to detect shape defects in the rolled product and
determined the degree of deformation of metal at thedesign
stage, which allows the initial plans to approximate the final
design as closely as possible. So this system is very helpful
for future researchers, would make it possible to avoid
having to perform a large number of costly and time-
consuming commercial trials and to predict the defects
might be formed in the rolled product [24].The variation of
the blade cross-section, the deformation stress and strain of
the work-piece keep changing during therollingprocessand
the conventional rolling theory is no longer valid. The
complexity and diversity of the blade cross-section
determine it impossible to establish a universal theoretical
model for the rolling process [25].Finite element method is
reliable and versatile analytical method that avoids bold
hypothesis, which are ofteninvolvedintheclassical methods
such as the slab method or the energy method [26].
(a)
(b)
(c)

(d)
Fig:1 The structure of the material after (a) rolling at
7500C, strain 0.14, (b) rolling at 9000C, strain 0.19, (c)
rolling at 10000C, strain 0.2, (d) rolling at 13000C, strain
0.18 [27]
The investigation of the Fe28Al3Cr iron aluminide
microstructure after rolling with draught of approx. 0.2 was
performed both by optical and transmission electron
microscopy. The recrystallized grains after rollingat10000C
and 13000C are visible as shown in figure 1. The shape of
grains after rolling at 750 and 9000C does not enable any
clear interpretation. Transmission electron microscopy
provides unambiguous information about the
microstructure [27].
Transverse Section
Longitudinal Section
Fig: 2 Effect of successive hot rolling particles uniformity
in Al6063-SiC particle size= 152µm [28]
In the case of the as-cast slabs, preparedwiththeapplication
of the optimum composite preparation route, the particle
distribution was found to be similar in both longitudinal and
transverse section. Application of successive hot rolling
resulted in a uniform particle distribution with particle
alignment in the rolling direction [28] as shown in figure 2.
2. PROBLEM DESCRIPTION
In this work the effective stress and strain is carried out in
steel angle bar during hot rolling operation with optimum
process parameter for prevent the edge crack inanglebar as
shown in figure 3.
Fig 3: Edge Crack
3. RESULTS AND DISCUSSION
The effective stress and strain is carried out in steel angle
bar during hot rolling operation with optimum process
parameter for prevent the edge crack in angle bar. The
diameter of the rollers andtemperatureofthematerial were
not changed as per industry requirement. Also limit of mill
speed was taken 110 rpm.
The simulation results were obtained in the terms of
effective plastic strain and effective stress distribution. The
acceptance criteria of plastic strain is 0.5 in hot rolling [29].
So the plastic strain value exceeds this limit then it will lead
edge cracks in steel angle bar.

(a)
(b)
(c)
Fig. 4: Effective Plastic Strain Distribution in Angle Bar at N=105
rpm, µ=0.20 (b) µ=0.25 (c) µ=0.30
(a)
(b)
(c)
Fig. 5 : Effective Plastic Strain Distribution in Angle Bar at N=110
rpm, (a) µ=0.20 (b) µ=0.25 (c) µ=0.30

In this work the ingot and rollers assembly was subjected to
mill speed of 105 and 110 rpm with friction coefficient 0.20,
0.25 and 0.30. The minimum effective plastic strain was
produced 0.5892 at N=105 rpm with frictioncoefficient0.20
and maximum effective plastic strain was produced 0.8864
at N=110 rpm (µ=0.20) as shown in figure 6.
(a)
(b)
(c)
Fig. 6: Effective Stress Distribution in Angle Bar at N=105
rpm,(a) µ=0.20 (b) µ=0.25 (c) µ=0.30
(a)
(b)
(c)
Fig. 7: Effective Stress Distribution in Angle Bar at N=110 rpm, at
µ=0.20 (b) µ=0.25 (c) µ=0.30
The ingot and rollers assembly was subjected to mill speed
of 90 rpm, 95 rpm and 100 rpm with frictioncoefficient0.20,
0.25 and 0.30. The maximum effective stress was produced

598.48 MPa at N=105 rpm with friction coefficient 0.30 and
minimum effective plastic strain was produced 528.89 MPa
at N=110 rpm (µ=0.30) as shown in figure 7.
(a)
(b)
(c)
Fig. 8: Effective Plastic Strain Variation with Mill Speed at
(a) µ=0.20 (b) µ=0.25 (c) µ=0.30
The effective plastic strain variation leads to some
interesting observation. The plastic strain is increased or
decreased between mill speeds 90 to 105 rpm at all
coefficient of friction, but after mill speed 105 rpm, the
plastic strain always increased rapidly as shown in figure 8.
(a)
(b)
(c)
Fig. 9: Effective Stress Variation with Mill Speed at
µ=0.20 (b) µ=0.25 (c) µ=0.30

The effective stress variation also leads to some interesting
observation in hot rolling mill operation. The stress
increased and decreased throughout the rolling mill speed,
and the maximum stress was observed at 598.48 MPa at
N=105 rpm with friction coefficient 0.30 and minimum
effective plastic strain was produced 528.89 MPa at N=110
rpm (µ=0.30) as shown in figure 9.
4. CONCLUSIONS
The analysis of the rolling process was done and results
obtained in terms of equivalent stress and effective plastic
strain. The effects of the friction on the rolling of steel angle
bar were studied for friction coefficient values of 0.20 to
0.30. The simulation results indicatethatthevalueoffriction
coefficient affects the effective stress and effective plastic
strain. The minimum effective plastic strain was produced
0.5892 at N=105 rpm with friction coefficient 0.20 and
maximum effective plastic strain was produced 0.8864 at
N=110 rpm (µ=0.20), whereas the maximum effectivestress
was produced 598.48 MPa at N=105 rpm with friction
coefficient 0.30 and minimum effective plastic strain was
produced 528.89 MPa at N=110 rpm (µ=0.30).
REFERENCES
[1] Myung-Sik Chun, Ick-Tae Ahn, and Young-Hoon
Moon,“Deformation Behavior of a Slab with Width
Reduction in a Hot Mill’’JMEPEG, 2005, pp. 408-412.
[2] S. Serajzadeh,“Effects of Rolling Parameters on Work-
Roll Temperature Distribution in the Hot Rolling of
Steels’’, Int J Adv Manuf Technol, 2008, pp. 859-866.
[3] Sun Jingna, Du Fengshan and Li Xuetong,‘‘FEM
Simulation of the Roll Deformation of Six-high CVC Mill
in Cold Strip Rolling’’, International Workshop on
Modelling, Simulation and Optimization, 2008, pp. 412-
415.
[4] Xianzhang FENG, Junwei CHENG, Cai LIU, Junhui LI and
Yanmei CUI, “Simulation of Mechanics Properties in
Rolling Process for H-beam’’, International Joint
Conference on Artificial Intelligence, 2009, pp.719-722.
[5] Manoj Saini , Navneet Arora , Chandan Pandey, Husain
Mehdi, Mechanical Properties of Bimetallic Weld Joint
between SA 516 Grade 65 Carbon Steel and SS 304LFor
Steam Generator Application, International Journal of
Research in Engineering and Technology,Vol 3(7)2014,
39-42.
[6] Manoj Saini , Navneet Arora , Chandan Pandey, Husain
Mehdi, Preliminary Studies on Thermal Cycling of
Reactor Pressure Vessel Steel, International Journal of
Mechanical EngineeringVol 4 (2), 2014, 51-58.
[7] Husain Mehdi, Shwetanshu Gaurav, Teetu Kumar,
Prasoon Sharma, Mechanical Characterization of SA-
508Gr3 and SS-304L Steel Weldments, International
Journal of Advanced Production and Industrial
Engineering vol 2, issue 1, 2017, 41-46.
[8] Yazhong sun, Xuming Shao and Zuobing Chen ,“Co-
simulation Analysis of Vertical Roller Mill Device Based
on Pro/E & ADAMS & ANSYS’’, International Conference
on Electronics, Communications and Control, 2011, pp.
3621-3625.
[9] Chang.Li, Guangbing and Zhao,Xing.Han,“FiniteElement
Analysis of Hot-Rolled Seamless Pipe Rolling Process
Elastic-Plastic Deformation’’, International Conference
on Electronic&Mechanical Engineering andInformation
Technology, 2011, pp. 557-560.
[10]Xiaokai Wang, Lin Hua, Xinghui Han, Xiaoxuan Wang,
Dehui Wang & Yali Liu, “Numerical Simulation and
Experimental StudyonGeometryVariationsand Process
Control Method of Vertical Hot ring Rolling’’,
International Journal of Advance Manufacturing
Technology, 2014, pp. 389-398.
[11]Huang Chang-qing, DENG Hua, DIAO Jin-peng and HU
Xing-hua, “Numerical Simulation ofAluminumAlloyHot
Rolling using DEFORM-3D’’.International Conferenceon
Computer Science and Automation Engineering, Vol.3,
2011, pp. 378-381
[12]Alexander Kainz, Sergiu Ilie, Erik Parteder and Klaus
Zeman,‘‘From Slab Corner Cracks to Edge-DefectsinHot
Rolled Strip, Experimental and Numerical
Investigations’’, Steel Research International, Vol.79,
February, 2008, pp. 861-867.
[13]Husain Mehdi Rajan Upadhyay, Rohan Mehra, Adit,
Modal Analysis of Composite Beam Reinforced by
Aluminium-Synthetic Fibers with and without Multiple
Cracks Using ANSYS, International journal ofMechanical
Engineering, vol-4 issue-2, pp 70-80, 2014.
[14]Husain Mehdi, Anil Kumar, Arshad Mehmood, Manoj
Saini, Experimental AnalysisofMechanical Propertiesof
Composite Material ReinforcedbyAluminium-Synthetic
Fibers, International journal ofMechanical Engineering,
vol-2, issue-2, pp-59-69, 2014
[15]K. Devarajan, K. Prakash Marimuthu & Dr.AjithRamesh,
“FEM Analysis of Effect of Rolling Parameters on Cold
Rolling Process’’, International Journal of Industrial
Engineering and Management Science, Vol. 2, No.1,
March, 2012, pp. 35- 40.
[16]Ju Chen, Ben Young, M.ASCE and Brian Uy, “Behavior of
High Strength Structural Steel at Elevated
Temperatures”, Journal of Structural Engineering,2006,
pp. 1948-1954.
[17]Dr. C. Fedorciuc – Onisa1, Dr. D.C.J. Farrugia,
‘‘Investigations into Roll Thermal Fatigue in Hot
Rolling’’, International Journal Mater, 2008, pp. 363–
366.
[18]Luca Giorleo, Claudio Giardini and Elisabetta
Cretti,‘‘Validation of Hot Ring Rolling Industrial Process
3 D Simulation’’, International Journal Mater, 2013,
pp.145-152.
[19]Rachit N. Singh and Dr. A. V. Vanalkar, ‘‘Analysis ofWear
Phenomena in Sliding Contact Surfaces’’, International
Journal of Engineering Research andApplications,Vol.2,
2012, pp. 2403-2409.

[20]C.G. Sun, C.S. Yun, J.S. Chung, and S.M. Hwang,
‘‘Investigation of Thermomechanical Behaviorofa Work
Roll and of Roll Life’’, Metallurgical and Material
Transaction a Vol.29, 1998, pp. 2407-2424.
[21]Raju D.V, Ankur Kumar & Dr. A. Mukhopadhyay, ‘‘Finite
Element Analysis of Rolls & Mill Housing in Cold Rolling
Mill’’, ABAQUS Users, Conference, 2004, pp. 551-561.
[22]M. A. Guerrero1, J. Belzunce, M C. Betegón, J. Jorge1&
Fco. J. Vigili, ‘‘Hot rolling process simulation,Application
to UIC-60 rail rolling’’, IASME/WSEAS International
Conference on Continuum Mechanics, 2009, pp. 213-
218.
[23]Tiago C.A. Colombo, Alberto M.G. Brito, and Lirio
Schaeffer, ‘‘Numerical SimulationofThermo-mechanical
Processes Coupled with Microstructure Evolution’’,
Computing in Science & Engineering, Vol.16, 2014,
pp.10-15.
[24]E.N. Chumachenko, L.V. Logashina and S.A. Aksenov
,‘‘Simulation Modelling Of Rolling In Passes’’, Springer
Science+Business Media, Vol.50, 2006, pp. 413-418.
[25]Kong Xiang-Wei and LI Jiaand LI Bin,“Finite element
analysis of rolling process for variable cross-section
blade”, J. Cent. South Univ. 20, 2006, pp. 3431-3436.
[26]Shigeru Ogawa, Shigeru Uchida,Yosuke Miura, Kenji
Yamada, Toshiyuki Shirashi, Yoshihiro Serizawa,
Tsuyoshi Inoue, Yasumitsu Konodo, Tooru Akashi
,Shinya Hayashi Yohji Nakamura, and Toshiaki Satio,
“Progress and Prospect of Rolling Technology’’, Nippon
Steel Technical Report No. 101,November,2012,pp.95-
103.
[27] Petr kratochvil and Lvo Schindler, Condition for Hot
Rolling of Iron Aluminide, Advanced Engineering
Materials, 6(5), 2004.
[28] Mohammad A, Taha Nahed A, El-MAhallawy and
Moneeb El-Sabbagh, Behavior of Stir-Cast Al-Alloy
particulate Reinforced Metal Matrix Composite under
Successive Hot Rolling,AdvancedEngineeringMaterials,
5(11), 2003
[29]Serope Kalpakjian and Steven Schmid, “Manufacturing
Processes For Engineering Materials”, Prentice Hall of
India. 5 Edition, 2007, pp. 41.

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