Welding is a common joint type in the fabrication of structural members in aerospace, aeronautical and pressure vessel industries. Welding is highly reliable and efficient metal joining process. The thermal response of materials to a welding heat source sometimes causes mechanical problems, e.g. residual stresses and distortion and changes in mechanical properties due to changes in the microstructure. The Finite Element Method (FEM) is the most commonly used numerical technique, which provides accurate estimates of thermal parameters for this analysis. Finite Element Analysis (FEA) is a tool used especially in determining the thermal stresses and temperature distribution of the welded models, which are difficult to analyze by hand calculations. The objective of the current work is to study transient temperature in both arc welded pipe and welded plate of 304L stainless steel. The object is modeled in 3D and analyzed using FEA with an element type of SOLID70 and heat density of the moving circular area heat source is used. Knowledge of temperature distribution patterns is useful in any welding process to predict microstructure and distortion. In the current work a model has been developed to predict the thermal cycles during welding of 304L pipeline steel

1. International Journal of Research in Advanced Technology - IJORAT
Vol. 2, Issue 1, JANUARY 2016
All Rights Reserved © 2015 IJORAT 1
FINITE ELEMENT SIMULATION OF
WELDING IN
STEEL PIPES AND PLATES
Mr. S.SHEIK SULAIMAN 1
, Mr. K.KRISHNAMOORTHY 2
, Mr.R.KARTHIKEYAN.3
Assistant Professor/Mechanical Engineering, Francis Xavier Engineering College, Tirunelveli, India1
Assistant Professor/Mechanical Engineering, Francis Xavier Engineering College, Tirunelveli, India2
Assistant Professor/Mechanical Engineering, Francis Xavier Engineering College, Tirunelveli, India3
Abstract: Welding is a common joint type in the fabrication of structural members in aerospace, aeronautical and
pressure vessel industries. Welding is highly reliable and efficient metal joining process. The thermal response of
materials to a welding heat source sometimes causes mechanical problems, e.g. residual stresses and distortion and
changes in mechanical properties due to changes in the microstructure. The Finite Element Method (FEM) is the most
commonly used numerical technique, which provides accurate estimates of thermal parameters for this analysis. Finite
Element Analysis (FEA) is a tool used especially in determining the thermal stresses and temperature distribution of
the welded models, which are difficult to analyze by hand calculations. The objective of the current work is to study
transient temperature in both arc welded pipe and welded plate of 304L stainless steel. The object is modeled in 3D and
analyzed using FEA with an element type of SOLID70 and heat density of the moving circular area heat source is used.
Knowledge of temperature distribution patterns is useful in any welding process to predict microstructure and
distortion. In the current work a model has been developed to predict the thermal cycles during welding of 304L
pipeline steel
Key words: Shot Peening, Surface Texturing, Intensity, Heat Treatment
I. INTRODUCTION
The investigation of many welding problems, such as
welding residual stresses, distortion, and micro structural
modeling, requires detailed information about the thermal
history of welded components and structures. Heat sources
play in essential role in most welding processes, as well as
thermal cutting and heat treatments in determining the
thermal history. If a component is locally heated thermal
flow will take place between regions of the heating body
from locations of higher temperature to the regions of lower
temperature, i.e., from the heated spot to the rest of the
heated body. The temperature gradient at each location of
the body depends upon the cooling rate of that location in
the heated component.
During welding processes, heat can be transmitted by
conduction, convection and radiation. For welding
processes where an electric arc is used as the welding heat
source, heat conduction through the metal body is the major
mode of heat transfer and heat convection is less significant
as for as the temperature field in the welded body is
concerned. The heat flow in the welding process presents a
very complex situation, which currently defines the detailed
analysis by analytical calculations. However, this problem
can be simplified by considering conduction only (on the
basis of the limited effect of radiation) and treating the
convection by making use of an arc efficiency parameter.
The specific features of the welding process is that
heating and cooling cycles occur very rapidly resulting in
very steep temperature gradients between welded areas and
the surrounding based metal. The base metal and fixtures
can also act as highly efficient heat sinks that could
increase cooling rates further depending on the conductivity
of the metal involved. This can cause undesirable micro
structures in the weld metal and Heat Affected Zone (HAZ).
.
II. GAS METAL ARC WELDING (GMAW)
The GMAW process is a reliable process when used
with solid state argon based shielding gases. This process has
been used as either a manual or mechanical technique in a
number of applications in terms of material type, thickness
and welding positions. High deposition rate can be achieved
by a mechanical operation at which the consumable electrode
is fed continuously into the weld arc. Normally GMAW was
used aluminium and argon as the shielding gas. However, for
steels, CO2 and Ar/ CO2 mixture is widely used as cover gas.
Fig (1) Schematic diagram of GMAW

2. International Journal of Research in Advanced Technology - IJORAT
Vol. 2, Issue 1, JANUARY 2016
All Rights Reserved © 2015 IJORAT 2
III. MODELED PIPE
The figure 4 shows welded pipe model. In this project to
model the pipe, assumed pipe dimensions are given in below
Outer diameter = 38 mm, Wall thickness = 2.3 mm and
Length = 203 mm.
Fig (2) Welded model of pipe.
IV. MODELED PLATE
The figure 5 shows welded plate model. In this project to
model the plate, assumed plate dimensions are given in below
Length = 55 mm, Width= 30 mm and Thickness= 2.3 mm.
Fig (3) welded model of plate.
V. FINITE ELEMENT MESHING OF PIPE
Fig (4) The meshed model of the pipe.
VI. FINITE ELEMENT MESHING OF PLATE
Fig (5) The finite element meshing of the plate
VII. THERMAL ANALYSIS
To calculate the heat input for arc welding
procedures, the following formula can be used
Where Q = heat input (W), V = voltage (V), I = current (A)
V=26 V, I =210 A, η= 60% and take welding speed
as 0.005 m/sec.
In this thermal analysis totally 120 load steps were
involved in the moving area circular heat source. Totally 24
seconds was consumed to complete the welding process. The
nodal temperature solutions were obtained from the thermal
analysis. Both the pipe and plate have same element type and
thermal analysis procedure. In this thermal analysis of plate
totally 30 load steps were involved in the moving area circular
heat source. Totally 6 seconds was consumed to complete the
welding process. In 3D analysis, during a time step, the
welding arc is allowed to stay at the element with constant
heat flux and then moved to next element.
If the amount of heat released is continuous from
to , then the temperature at point
at time t is the sum of the temperature increments due to series
of infinitesimal intervals
0),,,( TtzyxT 
=  










t
dt
ttatta
tta
z
tta
yvtx
c
Q
0
2
2
2
22
'
)'(4)'2)'(4(
)'(4'2)'(4
)'(
exp



generates a load-carrying pressure. This, in turn, reduces
surface wear.

3. International Journal of Research in Advanced Technology - IJORAT
Vol. 2, Issue 1, JANUARY 2016
All Rights Reserved © 2015 IJORAT 3
VIII. RESULTS AND DISCUSSION
TEMPERATURE DISTRIBUTION
Fig (6) Temperature distribution of welded pipe at 5 sec.
Fig (7) Temperature distribution of welded pipe at 5 sec.
Fig (8) Temperature distribution of welded pipe at 10 sec.
Fig (9) Temperature distribution of welded pipe at 10 sec.
Fig (10) Temperature distribution of welded pipe at 15 sec.
Fig (11) Temperature distribution of welded pipe at 15 sec.
Fig (12) Temperature distribution of welded pipe at 20 sec.
Fig (13) Temperature distribution of welded pipe at 20 sec.

4. International Journal of Research in Advanced Technology - IJORAT
Vol. 2, Issue 1, JANUARY 2016
All Rights Reserved © 2015 IJORAT 4
Fig (14) Temperature distribution of welded pipe at 24 sec.
Fig (15) Temperature distribution of welded pipe at 24 sec.
IX. TEMPERATURE HISTORY
Fig (16) Temperature history of welded pipe at node 9502.
Fig (17) Temperature history of welded pipe at node 9479.
Fig (18) Temperature history of welded pipe at node 9465.
Fig (19) Temperature history of welded pipe at node 9504.
Fig (20) Temperature history of welded pipe at node 9504 after cooling.
X. TEMPERATURE DISTRIBUTION OF PLATES

5. International Journal of Research in Advanced Technology - IJORAT
Vol. 2, Issue 1, JANUARY 2016
All Rights Reserved © 2015 IJORAT 5
Fig (21) Temperature distribution of welded plates at 2 sec.
Fig (22) Temperature distribution of welded plates at 5 sec.
Fig (23) Temperature distribution of welded plates at 3 sec.
Fig (24) Temperature history of welded plates at node 1487.
XI. CONCLUSION
Finite element method is an efficient technique in
welding simulation. Differences in physical, mechanical and
chemical properties of base metals cause non uniform
temperature distribution and heat transfer. Using a moving
heat source technique is provided to be reliable method to
simulate. Finally the results are compared with published
results.
The analysis results help us understand the
phenomena governing the welding of a joint, offering insight
on the mechanisms and mechanical aspect particular to the
welding process. Having understood the welding mechanism,
the effects of the welding can be better quantified and
therefore can be better addressed in the early stages of the
design.
ACKNOWLEDGMENT
I am using this opportunity to express my gratitude to
everyone who supported me throughout the project. I am
thankful for their aspiring guidance, invaluably constructive
criticism and friendy advice during the project work. I am
sincerely grateful to them for sharing their truthful and
illuminating views on a number of issues related to the project.
I would also like to thank to all the people who provided me
with the facilities being required and conductive conditions
for my project.
REFERENCES
[1] S.Nadimi., R.J.Khoushehmehr., B.Rohini and
A.Mostafapour.,“Investigation and Analysis of Weld
Induced Residual Stresses in Two Dissimilar Pipes
by Finite Element Modelling.” Journal of Applied
sciences 8 (6): 1014-1020, 2008.
[2] ANSYS guide, ANSYS release 10.0
[3] Xiangyang Lu and Tasnim Hassan., “Residual
Stresses in Butt and Socket Welded Joints.”
Transactions, SMiRT 16, Washington DC, August
2001.
[4] J.J.Dike., A.R.Ortega., C.H.Cadden., “Finite Element
Modeling and Validation of Residual Stresses in
304L Girth Welds.” 5th
International Conference on
Trends in Welding Research, June 1-5, 1998, Pine
Mountain, GA.
[5] Naeem Ullah Dar., Ejaz M.Qureshi., and M.M.I
Hammouda., “Analysis of Weld-induced Residual
Stresses and Distortions in Thin-walled Cylinders.”
Journal of Mechanical Science and Technology 2
(2009) 1118-1131.
[6] N.T. Nguyen., “Thermal Analysis of Welds.” ETRS
Pvt Ltd, WIT press, Australia, 2004.
[7] John.A.Goldak and Mehdi Akhlaghi.,
“Computational Welding Mechanics.” Published by
springer.