Finite element analysis (FEA) is a computational technique used to approximate solutions to boundary value problems in engineering. It involves discretizing a physical domain into small elements and calculating field variables at specific points called nodes. Rolling simulations were conducted to analyze the effects of varying roller speed, diameter, and other parameters on stress and pressure. The optimum parameters found were a coefficient of friction of 0.45, plate feed speed of 1.5 m/s, and roller velocity of 9 rad/s, which resulted in lower residual stresses. Asymmetrical rolling was also discussed as an alternative approach with benefits like less rolling pressure but potential issues like mill vibration.

1. FEA Application OF Forming
Process
(rolling of thick plate)

2. Introduction
• Is a computer technology used to obtain approximate solutions
to boundary value problems in engineering. Simply
• relying on two methods Before the advent of the computer was
• the book ROARK IS FORMUALS
• By making traditional calculations

3. How does the program deal with problem solving?
• By specifying the item type plus some insert parameters

4. What is finite element analysis ?
a finite element analysis (FEA), is a computational technique used to obtain
approximate solutions of boundary value problems in engineering
a boundary value problem is a mathematical problem in which one or more
dependent variables must satisfy a differential equation everywhere within a
known domain of independent variables and satisfy specific conditions on
the boundary of the domain
The boundary conditions are the specified values of the field
variables (or related variables such as derivatives) on the boundaries of the
field.
Depending on the type of physical problem being analyzed

5. HOW DOES THE FINITE ELEMENT METHOD WORK?
• The volume represents the domain of a boundary value problem to
be solved .
• A node is a specific point in the finite element at which the value of
the field variable is to be explicitly calculated. Exterior nodes are
located on the boundaries of the finite element and may be used to
connect an element to adjacent finite elements.
• Nodes that do not lie on element boundaries are interior nodes and
• cannot be connected to any other element
• The values of the field variable computed at the nodes are used to
approximate the values at nonnodal points (that is, in the element
• interior) by interpolation of the nodal values

6. Finite Element and Exact Solutions
• The process of representing a physical domain with finite elements is
referred to as meshing, and the resulting set of elements is known as
the finite element mesh
• as the number of elements is increased and
• the physical dimensions of the elements are decreased, the finite
element solution changes incrementally. The incremental changes
decrease with the mesh refinement process and approach the exact
solution asymptotically
• .

7. Rolling Case study
(manipulating rolling parameters to
enhance rolling process)
By using Finite Element Analysis
ABQUS

8. The main interest of this study is to see how to
reduce contact pressure by the changing of rolling
process factors.
Problem definition:

9. PROBLEM DEFINITION
Case No
Rolls
rpm
Roll initial
velocity in
m/s
Roll
Diameter in
mm
Friction
1 30 1.037 100 0.3
2 60 1.037 150 0.3
3 120 1.037 200 0.3
4 240 1.037 250 0.3
5 320 1.037 275 0.3
6 480 1.037 300 0.3
Parameters used:
• Rolling through the one roll stand
• The two-dimensional rolling of thick plates
• The roller was modeled as rigid
• Assumed thick plate was Isotropic elasticity
• Strain hardening is described in Table 2.
• The methodology is used for this study Plane strain problem
• Element = CPE4R and Explicit Dynamic
• No rate dependence and temperature dependence are
taken into account
Reducing von-mises stresses and contact pressure by simulating rolling
process and finding optimum rolling parameters (the roller speed and the
diameter of the roller ) Parameter value
Plate dimensions 40*40*100
Reduction percent % 17.5%
Young's modulus(E) 150 GPa
Poisson's ratio 0.33
initial velocity 1.037 m/s

10. Yield Stress
(Mpa)
Plastic
Strain
168.72 0
219.33 0.1
272.02 0.2
308.53 0.3
337.37 0.4
361.58 0.5
382.65 0.6
401.42 0.7
418.42 0.8
434.01 0.9
448.45 1
PROBLEM DEFINITION

11. Simulation & Analysis

12. Simulation & Analysis

13. Simulation & Analysis

14. 0
50
100
150
200
250
300
350
400
450
0 10 20 30 40 50 60 70 80
320rpm 240 rpm 480rpm
Simulation & Analysis
Arc of Contact for Different Roller speed and Contact Pressure for Case240,320,480 rpm for Constant Roller
Diameter=250mm and Friction=0.3

15. Simulation & Analysis

16. Simulation & Analysis

17. Simulation & Analysis

18. Simulation & Analysis
280
282
284
286
288
290
292
294
200 210 220 230 240 250 260 270 280 290
Simulation vs it's trendline
. Graph between Different Roller Diameter and Von-Mises Stress for Constant Roller Speed=240 rpm and Constant
Friction =0.3

19. Roll biting Problem

20.  CASE:
1. Roll diameter= 200
2. reduction= 10mm
3. length of 100 mm
4. Roll speed = 240 rpm
5. Coefficient of friction = 0.3
6. rolling through the one roll stand
7. the two-dimensional rolling of thick plates
8. The roller was modeled as rigid
Problem definition:
When simulating the rolling process with the previous condition the strip is bent from the start;
unnecessary deformation is done leading to either defecting rolls or-in this case- lead to sheet
distortion
Roll biting Problem

21. Roll biting Problem
Problem analysis:
µ>=tanα
Δh max = µ2 R
From the equation above we found that µ should be 0.316 not 0.3 or Δh max = 9mm (since µmax at cold rolling
doesn’t exceed 0.3) so; The roll biting condition won’t happen but by excessive velocity given at the start of the
process the sheet bends till the initial thickness is equal to 9 the process proceeded
Also the stress is increased a lot the other cases

22. Investigation about FEM in rolling processes in industry

23. About the company
• ESSAR Steel, Hazira is a name renowned within the Rolling Industry. It
has the most vast amount of rolling facilities in the country and the
various complexes that are involved in the Rolling process are as
follows :
• Iron Making Facility
• Hot Roll Mill
• Cold Roll

24. project analysis
The concern with cold rolling process only and intend to obtain the
influence of various parameters such as Co-efficient of friction, Plate
feed speed and Roller Velocity on outputs like Von-Mises Stress

25. Analysis assumption
• The arc of contact between the rolls and the metal is a part of a circle.
• The coefficient of friction, μ, is constant in simulation, but in actual
scenario,
• μ varies along the arc of contact.
• The metal is considered to deform plastically during rolling.
• The volume of metal is constant before and after rolling. In actual scenario,
• the volume might decrease a little bit due to close-up of pores.
• The velocity of the rolls is assumed to be constant.
• The metal only extends in the rolling direction and no extension in the
• width of the material.
• The cross sectional area normal to the rolling direction is not distorted

26. Sheet simulation model
• Based on our Initial Basic Simulation Model, the industry provided to
them this dimention
Dimension value
Length 1500 mm
Initial Sheet Thickness 5 mm
Final Sheet Thickness 4 mm
Sheet Feed Velocity 1.5 m/s
Roller Diameter 380 mm
Roller Velocity 200 MPM (20 Rad/s)
Initial Material Hardness 50-60 HRB
Post-Rolling Material Hardness 90 HRB
Post-Annealing Material Hardness
60 HRB

27. Result

28. Conclusion
the most optimum combination of parameters which would result in
an overall reduction in the residual stresses.
• Co-efficient of Friction f = 0.45
• Velocity of Plate Feed VP = 1.5 m/s
• Velocity of Roller VR = 9 rad/s

29. Asymmetrical

32. Advantages Disadvantages
a) Less rolling pressure.
b) Less rolling force.
c) Less rolling torque.
d) Better properties of the strip surface.
e) Improvement of plate shape.
a) mill vibration
b) wrinkles on the plate surface
There exist three different asymmetrical rolling
processes:
1. Produced by using different peripheral velocities with the same roll radius.
2. Using different radii with the same angular velocity.
3. Using varying coefficients of friction for the two work rolls and keeps the
peripheral velocity and roll radius the same for the two work rolls.

33. Thank you