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Design and analysis of a portable friction stir welding machine
Available online at www.sciencedirect.com
ScienceDirect Materials Today: Proceedings 5 (2018) 19340–19348
www.materialstoday.com/proceedings
ICMPC_2018
Design and analysis of a portable friction stir welding machine R. Rohith Renisha, Arun Pranesh Mb,*, K. Logesha a
Assistant Professor, Department of Mechanical Engineering,Veltech Dr.RR & Dr.SR University, Chennai, India. Assistant Professor, Department of Mechanical Engineering, Kathir College of Engineering, Coimbatore, India.
b
Abstract Friction stir welding is a mechanism to combine two solid metals without melting. This technique is much preferred for its flexibility, energy efficient, and also environment friendly as it results in high quality welding with low shrinkage. But these machines are giant and also consume more power. In order to address this problem, a portable friction stir welding machine has been designed and analysed. In this study, a machine has been designed to weld plates of 2mm thickness at low power consumption. This could be very much beneficial for the onsite welding processes and also to weld materials of less thickness. The design was done in four stages and the fourth stage was finally analysed for 2 tonne load and the plots are also shown in results and discussion for stress, displacement, strain and factor of safety. The analysis of overall factor of safety of the portable friction stir welding machine shows that all the components are safe except the transverse drive with a Factor of safety 1.431e001 which is considered to be safe because the applied load is double to that of the required load. The Structural static analysis also was successfully completed using Solid Works by applying 2 tonne load and the results of various parameters such as stress, displacement, strain were plotted and tabulated. © 2018 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of Materials Processing and characterization. Keywords: Portable FSW machine; Stress and strain analysis; 2mm plate;
1. Introduction Friction stir welding is a solid state welding process that is used to join metals like aluminium, nickel, titanium etc, just by the heat that is produced by the rotating tool[1]. This welding was invented by W.Thomas and E Nicholas at The Welding Institute in UK at 1991[1,2]. The term friction welding has been existing for more than 100 years and it is commonly used for joining rod or pipe shaped materials. *Corresponding author. Tel.: +919003660194 E-mail address: [email protected] 2214-7853 © 2018 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of Materials Processing and characterization.
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
19341
Nomenclature FOS Factor of Safety FSW Friction stir welding N Newton m metre
In this case ,the materials are bought in contact with one another causing friction resulting in heat generation when both the materials are pushed against one another with an external force[7]. But in the case of Friction stir welding, it makes use of a non consumable rotating tool to generate frictional heat over the work piece[4,5,8]. The major use of friction stir welding could be said that it is used to join even dissimilar materials, including enhanced mechanical properties, at low cost and without any filler material[6,11]. The currently available FSW machines are Column based machines thus they have constrain in the portability and operations during machining. They are not easy to dismantle and are not portable for onsite welding. Friction welding machines are generally similar to lathe and drill. The first friction welding machines are modified forms of these machine tools. Friction welding machines are allmechanized machines. Joining and releasing of parts, turning of capillary produced due to accumulation after welding are automatically accomplished. The main functions in friction welding are joining, compressing and releasing of parts, rotation and friction under pressure, braking, accumulation and meticulous adjustments of required processing times. Sample joining apparatus needs to have certain rigidity, must resist increased moments, and must eliminate vibrations and leaks. Especially, possible vibrations during welding process need to be taken into account while designing the friction welding machine. In addition to vibrations, other radial and axial forces have to be accounted for. Therefore, joining apparatus has to have a design which will counter compressing forces. Thus a machine is to be designed in a modular approach so that there will be less constrains and could be portable. Friction welding is very commonly used in automotive industries as well as in aeronautical industries [10-12] as it allows to join high strength alluminium alloys such as 7000 and 2000series and also other metals which are found difficult to be joint by the conventional joining process[11-14]. 2. Materials and Methodology Friction welding is more preferred than any other conventional welding method because metals can be joined at temperatures lower than their melting[9] point and also with very less time duration. Basically for designing a friction stir welding machine there are some basic components that is much necessary that it cannot be compromised with any other components. The work is started up by designing a base plate which must have enough thickness and strength to tolerate the compression force during welding. The spindle which is attached to the horizontal beam or guide rods must be able to withstand enough pressure by the opposing force. The horizontal movement in the X as well as Y directions are to be arrested and also it is necessary to keep the plates intact so that the gap between the plates in minimum[3]. Friction welding of metals having different thermal and mechanical properties causes asymmetrical deformations. Steels with lower strength can be more easily joined with a large parameter range. In this work the conceptual designs have been made with the help of Solid Works. These designs are also analysed by giving an initial load of 2 tonne. The basic movement in this kind of application is the rotational movement causing friction. Relatively high overhead cost is balanced with higher production rate and requirement of low labour. Process has several dimensions and hardware could easily be adjusted. 3. Result and Discussion 3.1 Conceptual Design - Stage 1 In stage 1, the design is made in such a way that there would be proper distribution of force that acts on the beams during machine operations. This design consists of a base over which the columns have been placed. These columns are movable with the help of the screw rods. To make the opposing force distributed the motor holder was fixed on the simply supported beam and the vertical beams and simply supported beam was connected using V-grooves. So
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R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
that the force will not stress more on the screw rod and the distribution of load will be equal. Hence the analysis has been made over these columns and the beam to make sure that it could resist the opposing force. Figure 1 (a-f) shows all the components that are required for FSW machining. In final design the base is designed with screw rods for longitudinal drive. Screw rods are used so that the longitudinal movement will not be affected due to vibration. The results after analysis show that the stress acting upon the machine is transferred to the beam through the spindle as it experiences an opposing force during welding. The maximum load is assumed to be 2 tonne acting on the machine which is almost double the required load. The readings from the analysis are plotted in table 1. a)
b)
Base of the machine for mounting the work-piece
Screw rod for longitudinal drive
c)
d) Displacement is high in this region
Stress is more at these points
e)
f)
Strain is more at this point
Fig 1. Stage 1 a) Conceptual design b) Conceptual design with base c) Stress plot d) Displacement Plot e) Strain Plot f) Plot for Factor of Safety
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
19343
Table: 1 Analysis results for the stage 1 2 tonne
Applied Load Min
Max
Stress(vonmises) (N/m^2)
247.5
59691360.0
Displacement URES (m)
1.1017e-009
6.273e-005
Strain
8.585e-010
2.389e-004
FOS
4.64
3.2 Conceptual Design - Stage 2 The fig 2 (a) shows the 2nd stage design of portable friction stir welding machine. This design was done to reduce the manufacturing cost and make an efficient portable machine. But the design was complicated for manufacturing and assembly, while designing the assembling and disassembling of the machine was not considered, resulting which the screw rod of transverse drive and longitudinal drive over lapped each other. The manufactured product of this design could weigh around 200kgs which is more than what was expected. The problem of over lapping of screw rod and complexity in manufacturing and assembly was rectified in fig 2(b). Some of the unnecessary components from 2(a) were removed in this case. This design also could not satisfy the requirement of portability due to the materials thickness and also will result in too much of cost. The weight of machine could result in around 120kgs which is also too heavy. Many possible ways to optimize and reduce the weight was tried but this could weaken the machine. This led to stage 2 (c) where the arrangements of the machine were varied and also reducing the components weight without loosing its strength. In fig 2(c), the height of the machine was reduced and the thickness of sheet for the body of machine was reduced in order to reduce the total weight of the machine. There were few other arrangements that were made for the machine to reduce the weight but it still became worse and made the machine very weak. So an alternative way to reduce the machine’s weight is to be found. This method too many screw rods as well as guide rods were put in for the horizontal and vertical movements . It was a failure design since the full load acts over the screw rod through the spindle. So the next stage was tried to bring up the design with minimum screw rods. Table 2 shows the static analysis values for 2 tonne load for stage 2 design of fig 2(c). The plots for stress, displacement, strain and factor of safety of the machine are shown in fig 2(d), 2(e), 2(f), 2(g) a)
b)
c)
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R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
d)
e) Maximum stress
Maximum Displacement
f)
g) Maximum Strain
Fig 2 Stage 2 a) Conceptual Design 2 i b) Conceptual Design 2 ii d) Stress plot for 2 iii `
c) Conceptual Design 2 iii
e) Displacement Plot for 2 iii f) Strain Plot for 2 iii g) Plot for Factor of Safety for 2 iii
Table: 2 Analysis results for the stage 2 Applied Load
Stress(vonmises) (N/m^2)
2 tonne Min
Max
35.1
24106094
Displacement URES (m)
1.00e-033
4.936e-005
Strain
1.122e-009
1.415e-004
FOS
11.73
3.3 Conceptual Design – Stage 3 In this phase the design was changed due to the restriction in the vertical and longitudinal movement in the machine. This machine was carefully designed by considering all the problems that caused in previous stages of design. In order to reduce the weight of the machine two plates were bolt together to give more strength where ever necessary. This design is made with plates so that it will be easy to assemble and disassemble. Fig 3(a-e) shows the design of stage 3, where it has a screw rod for the horizontal movement supported by 2 guide rods. But in this design the load acting on the spindle will transfer it to the column as there isn’t much support for the column at the bottom. This design could be considered safe when compared to that of the previous 2 stages but still it has its own drawbacks.
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
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a)
b)
c) Maximum Displacement
Maximum stress
d)
e) Maximum Strain
Fig 3. Stage 3 a) Conceptual design b) Stress plot c) Displacement Plot d) Strain Plot e) Plot for Factor of Safety
Table 3 shows the static analysis values for 2 tonne load for stage 3 design. And the plots for stress, displacement, strain and factor of safety of the machine are shown in figures 3(b), 3(c), 3(d), 3(e).
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R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
Table: 3 Analysis results for the stage 3 2 tonne
Applied Load Min
Max
Stress(vonmises) (N/m^2)
0.0
23652790
Displacement URES (m)
1.000e-033
5.050e-006
0.000e+0000
2.056e-004
Strain FOS
11.63
These analysis result show that the design is safe but still it has to be designed for a fully automatic operation thus moving on to next stage of design. 3.4 Conceptual Design – Stage 4 The fig 4(a-e) shows the typical deign of the Conceptual Design–Stage 4. The previous design was safe and satisfied all the requirements that needed for a friction stir welding process. But it is necessary to make this machine automatic so limit switches are to be added. Transverse, longitudinal and vertical movements are constructed properly so that there could be no problem during machining. In this stage the screw rods are eliminated and are replace with rail guide. The overall construction of the machine is made sure that the assembling and disassembling of the machine is done easily and also it will be easier for replacing any defected or worn-out parts in future without any difficulty as shown in below Table 4. a)
b)
c) Maximum stress
Maximum Displacement
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
d)
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e) Maximum Strain
Fig 4. Stage 4 a) Conceptual design b) Stress plot c) Displacement Plot d) Strain Plot e) Plot for Factor of Safety Table: 4 Analysis results for the final stage 4 2 tonne
Applied Load Min
Max
Stress(vonmises) (N/m^2)
0
1149069952
Displacement URES (m)
1.00e-030
8.264e-001
Strain
0.00e+00
4.646e-003
FOS
1.431e-001
4. Conclusion The design developed at the fourth stage would be much preferred as it satisfies all the conditions when compared to that of the other 3 stages. The following observations were made in the static analysis plots for stress, displacement, strain and factor of safety at the fourth stage. a) In stress plot the regions with high stress value were analysed and seemed to be safe. b) In displacement plot the motor hold seem to have high deflection so it has to be optimized and corrected. c) In strain plot the transverse drive rod have a high value at a point where the motor hold is sliding through thus the transverse drive is also to be optimized. d) In the analysis of the overall factor of safety of the portable friction stir welding machine show that all the parts are safe expect the transverse drive with a factor of safety of 1.431e-001 which is safe because the applied load is double the required load. The Structural static analysis also was successfully completed using Solid Works by applying 2 tonne load and the results of various parameters like stress, displacement, strain are plotted and tabulated. 5. References [1] Gurunath Shindea, Sameer Gajghate , Dr.P.S.Dabeer , Dr.C.Y. Seemikeri , Low Cost Friction Stir Welding: A Review, Materials Today: Proceedings 4 (2017) pp 8901–8910 [2] W.M. Thomas, E.D. Nicholas, J.C. Needham, M.G. Much, P. Temple-Smith, C.J. Dawas, Friction stir butt welding, GB Patent No. 9125978.8, International patent application No. PCT/GB92/02203,(1991). [3] L.V. Kamble, S.N. Soman, P.K. Brahmankar, Understanding the Fixture Design for friction stir welding research experiments, Materials Today: Proceedings 4 (2017) pp 1277–1284 [4] Fujii, H., Cui, L., Maeda, M., Nogi, K. Effect of tool shape on mechanical properties and microstructure of friction stir welded aluminum alloys., Materials Science and Engineering (2006) A419, 25–31.
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R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
[5] Starink, M.J., Deschamps, A., Wang, S.C, The strength of friction stir welded and friction stir processed aluminium alloys., Scripta Materialia (2008) 58, 377–382. [6] P.L. Threadgill, A.J. Leonard, H.R. Shercliff, P.J. Withers, Friction stir welding of aluminum alloys, Int. Mater. Rev. 54 (2009) 49-93. [7] Dalder E N, Pastrnak J W, Engel J, Forrest R S, Kokko E, McTernan K and Waldron D , “Bobbin-Tool Friction Stir Welding of Thick-Walled Aluminum Alloy Pressure Vessels”, Welding Journal (AWS), April (2008) pp. 40-44. [8] Buffa G, Fratini L, Merklein M and Staud D, Key Engineering Materials, Vol. 344, (2007) pp. 143-150. [9] Gianluca Buffa, Davide Campanella, Rosa Di Lorenzo , Livan Fratini and Giuseppe Ingarao, Analysis of electrical energy demands in Friction Stir Welding of aluminum alloys, Procedia Engineering 183 ( 2017 ) pp 206 – 212 [10] Lee, J.A., Carter, R.W., Ding, J. Friction Stir Welding for Aluminium Metal Matrix Composites (MMC’s). MSFC Center Director’s Discretionary Fund Final Report, Project No. 89-09, NASA/TM, MSFC – Alabama 35812. December (1999) 1–20 [11] Mishra, R.S., Ma, Z.Y. Friction stir welding and processing. Material Science and Engineering R (2005) 50, 1–78. [12] Thomas, W.M. Friction Stir Welding of Ferrous Materials: A Feasibility Study, 1st International Symposium on Friction Stirs Welding, Rockwell Science Centre, Thousand Oaks, CA, USA, June (1999) [13] Gachi, S.; Belahcene, F.; Boubenider, F. Residual stresses in AA7108 aluminium alloy sheets joined by friction stir welding. Journal of Nondestructive Testing and Evaluation (2009) 24, 301–309. [14] Thomas, W.M.; Dolby, R.E. Friction Stir Welding Developments, 6th International Conference on Trends in Welding Research, Pin Mountain – Georgia (2002)
ScienceDirect Materials Today: Proceedings 5 (2018) 19340–19348
www.materialstoday.com/proceedings
ICMPC_2018
Design and analysis of a portable friction stir welding machine R. Rohith Renisha, Arun Pranesh Mb,*, K. Logesha a
Assistant Professor, Department of Mechanical Engineering,Veltech Dr.RR & Dr.SR University, Chennai, India. Assistant Professor, Department of Mechanical Engineering, Kathir College of Engineering, Coimbatore, India.
b
Abstract Friction stir welding is a mechanism to combine two solid metals without melting. This technique is much preferred for its flexibility, energy efficient, and also environment friendly as it results in high quality welding with low shrinkage. But these machines are giant and also consume more power. In order to address this problem, a portable friction stir welding machine has been designed and analysed. In this study, a machine has been designed to weld plates of 2mm thickness at low power consumption. This could be very much beneficial for the onsite welding processes and also to weld materials of less thickness. The design was done in four stages and the fourth stage was finally analysed for 2 tonne load and the plots are also shown in results and discussion for stress, displacement, strain and factor of safety. The analysis of overall factor of safety of the portable friction stir welding machine shows that all the components are safe except the transverse drive with a Factor of safety 1.431e001 which is considered to be safe because the applied load is double to that of the required load. The Structural static analysis also was successfully completed using Solid Works by applying 2 tonne load and the results of various parameters such as stress, displacement, strain were plotted and tabulated. © 2018 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of Materials Processing and characterization. Keywords: Portable FSW machine; Stress and strain analysis; 2mm plate;
1. Introduction Friction stir welding is a solid state welding process that is used to join metals like aluminium, nickel, titanium etc, just by the heat that is produced by the rotating tool[1]. This welding was invented by W.Thomas and E Nicholas at The Welding Institute in UK at 1991[1,2]. The term friction welding has been existing for more than 100 years and it is commonly used for joining rod or pipe shaped materials. *Corresponding author. Tel.: +919003660194 E-mail address: [email protected] 2214-7853 © 2018 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of Materials Processing and characterization.
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
19341
Nomenclature FOS Factor of Safety FSW Friction stir welding N Newton m metre
In this case ,the materials are bought in contact with one another causing friction resulting in heat generation when both the materials are pushed against one another with an external force[7]. But in the case of Friction stir welding, it makes use of a non consumable rotating tool to generate frictional heat over the work piece[4,5,8]. The major use of friction stir welding could be said that it is used to join even dissimilar materials, including enhanced mechanical properties, at low cost and without any filler material[6,11]. The currently available FSW machines are Column based machines thus they have constrain in the portability and operations during machining. They are not easy to dismantle and are not portable for onsite welding. Friction welding machines are generally similar to lathe and drill. The first friction welding machines are modified forms of these machine tools. Friction welding machines are allmechanized machines. Joining and releasing of parts, turning of capillary produced due to accumulation after welding are automatically accomplished. The main functions in friction welding are joining, compressing and releasing of parts, rotation and friction under pressure, braking, accumulation and meticulous adjustments of required processing times. Sample joining apparatus needs to have certain rigidity, must resist increased moments, and must eliminate vibrations and leaks. Especially, possible vibrations during welding process need to be taken into account while designing the friction welding machine. In addition to vibrations, other radial and axial forces have to be accounted for. Therefore, joining apparatus has to have a design which will counter compressing forces. Thus a machine is to be designed in a modular approach so that there will be less constrains and could be portable. Friction welding is very commonly used in automotive industries as well as in aeronautical industries [10-12] as it allows to join high strength alluminium alloys such as 7000 and 2000series and also other metals which are found difficult to be joint by the conventional joining process[11-14]. 2. Materials and Methodology Friction welding is more preferred than any other conventional welding method because metals can be joined at temperatures lower than their melting[9] point and also with very less time duration. Basically for designing a friction stir welding machine there are some basic components that is much necessary that it cannot be compromised with any other components. The work is started up by designing a base plate which must have enough thickness and strength to tolerate the compression force during welding. The spindle which is attached to the horizontal beam or guide rods must be able to withstand enough pressure by the opposing force. The horizontal movement in the X as well as Y directions are to be arrested and also it is necessary to keep the plates intact so that the gap between the plates in minimum[3]. Friction welding of metals having different thermal and mechanical properties causes asymmetrical deformations. Steels with lower strength can be more easily joined with a large parameter range. In this work the conceptual designs have been made with the help of Solid Works. These designs are also analysed by giving an initial load of 2 tonne. The basic movement in this kind of application is the rotational movement causing friction. Relatively high overhead cost is balanced with higher production rate and requirement of low labour. Process has several dimensions and hardware could easily be adjusted. 3. Result and Discussion 3.1 Conceptual Design - Stage 1 In stage 1, the design is made in such a way that there would be proper distribution of force that acts on the beams during machine operations. This design consists of a base over which the columns have been placed. These columns are movable with the help of the screw rods. To make the opposing force distributed the motor holder was fixed on the simply supported beam and the vertical beams and simply supported beam was connected using V-grooves. So
19342
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
that the force will not stress more on the screw rod and the distribution of load will be equal. Hence the analysis has been made over these columns and the beam to make sure that it could resist the opposing force. Figure 1 (a-f) shows all the components that are required for FSW machining. In final design the base is designed with screw rods for longitudinal drive. Screw rods are used so that the longitudinal movement will not be affected due to vibration. The results after analysis show that the stress acting upon the machine is transferred to the beam through the spindle as it experiences an opposing force during welding. The maximum load is assumed to be 2 tonne acting on the machine which is almost double the required load. The readings from the analysis are plotted in table 1. a)
b)
Base of the machine for mounting the work-piece
Screw rod for longitudinal drive
c)
d) Displacement is high in this region
Stress is more at these points
e)
f)
Strain is more at this point
Fig 1. Stage 1 a) Conceptual design b) Conceptual design with base c) Stress plot d) Displacement Plot e) Strain Plot f) Plot for Factor of Safety
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
19343
Table: 1 Analysis results for the stage 1 2 tonne
Applied Load Min
Max
Stress(vonmises) (N/m^2)
247.5
59691360.0
Displacement URES (m)
1.1017e-009
6.273e-005
Strain
8.585e-010
2.389e-004
FOS
4.64
3.2 Conceptual Design - Stage 2 The fig 2 (a) shows the 2nd stage design of portable friction stir welding machine. This design was done to reduce the manufacturing cost and make an efficient portable machine. But the design was complicated for manufacturing and assembly, while designing the assembling and disassembling of the machine was not considered, resulting which the screw rod of transverse drive and longitudinal drive over lapped each other. The manufactured product of this design could weigh around 200kgs which is more than what was expected. The problem of over lapping of screw rod and complexity in manufacturing and assembly was rectified in fig 2(b). Some of the unnecessary components from 2(a) were removed in this case. This design also could not satisfy the requirement of portability due to the materials thickness and also will result in too much of cost. The weight of machine could result in around 120kgs which is also too heavy. Many possible ways to optimize and reduce the weight was tried but this could weaken the machine. This led to stage 2 (c) where the arrangements of the machine were varied and also reducing the components weight without loosing its strength. In fig 2(c), the height of the machine was reduced and the thickness of sheet for the body of machine was reduced in order to reduce the total weight of the machine. There were few other arrangements that were made for the machine to reduce the weight but it still became worse and made the machine very weak. So an alternative way to reduce the machine’s weight is to be found. This method too many screw rods as well as guide rods were put in for the horizontal and vertical movements . It was a failure design since the full load acts over the screw rod through the spindle. So the next stage was tried to bring up the design with minimum screw rods. Table 2 shows the static analysis values for 2 tonne load for stage 2 design of fig 2(c). The plots for stress, displacement, strain and factor of safety of the machine are shown in fig 2(d), 2(e), 2(f), 2(g) a)
b)
c)
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R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
d)
e) Maximum stress
Maximum Displacement
f)
g) Maximum Strain
Fig 2 Stage 2 a) Conceptual Design 2 i b) Conceptual Design 2 ii d) Stress plot for 2 iii `
c) Conceptual Design 2 iii
e) Displacement Plot for 2 iii f) Strain Plot for 2 iii g) Plot for Factor of Safety for 2 iii
Table: 2 Analysis results for the stage 2 Applied Load
Stress(vonmises) (N/m^2)
2 tonne Min
Max
35.1
24106094
Displacement URES (m)
1.00e-033
4.936e-005
Strain
1.122e-009
1.415e-004
FOS
11.73
3.3 Conceptual Design – Stage 3 In this phase the design was changed due to the restriction in the vertical and longitudinal movement in the machine. This machine was carefully designed by considering all the problems that caused in previous stages of design. In order to reduce the weight of the machine two plates were bolt together to give more strength where ever necessary. This design is made with plates so that it will be easy to assemble and disassemble. Fig 3(a-e) shows the design of stage 3, where it has a screw rod for the horizontal movement supported by 2 guide rods. But in this design the load acting on the spindle will transfer it to the column as there isn’t much support for the column at the bottom. This design could be considered safe when compared to that of the previous 2 stages but still it has its own drawbacks.
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
19345
a)
b)
c) Maximum Displacement
Maximum stress
d)
e) Maximum Strain
Fig 3. Stage 3 a) Conceptual design b) Stress plot c) Displacement Plot d) Strain Plot e) Plot for Factor of Safety
Table 3 shows the static analysis values for 2 tonne load for stage 3 design. And the plots for stress, displacement, strain and factor of safety of the machine are shown in figures 3(b), 3(c), 3(d), 3(e).
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R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
Table: 3 Analysis results for the stage 3 2 tonne
Applied Load Min
Max
Stress(vonmises) (N/m^2)
0.0
23652790
Displacement URES (m)
1.000e-033
5.050e-006
0.000e+0000
2.056e-004
Strain FOS
11.63
These analysis result show that the design is safe but still it has to be designed for a fully automatic operation thus moving on to next stage of design. 3.4 Conceptual Design – Stage 4 The fig 4(a-e) shows the typical deign of the Conceptual Design–Stage 4. The previous design was safe and satisfied all the requirements that needed for a friction stir welding process. But it is necessary to make this machine automatic so limit switches are to be added. Transverse, longitudinal and vertical movements are constructed properly so that there could be no problem during machining. In this stage the screw rods are eliminated and are replace with rail guide. The overall construction of the machine is made sure that the assembling and disassembling of the machine is done easily and also it will be easier for replacing any defected or worn-out parts in future without any difficulty as shown in below Table 4. a)
b)
c) Maximum stress
Maximum Displacement
R. Rohith Renish et al./ Materials Today: Proceedings 5 (2018) 19340–19348
d)
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e) Maximum Strain
Fig 4. Stage 4 a) Conceptual design b) Stress plot c) Displacement Plot d) Strain Plot e) Plot for Factor of Safety Table: 4 Analysis results for the final stage 4 2 tonne
Applied Load Min
Max
Stress(vonmises) (N/m^2)
0
1149069952
Displacement URES (m)
1.00e-030
8.264e-001
Strain
0.00e+00
4.646e-003
FOS
1.431e-001
4. Conclusion The design developed at the fourth stage would be much preferred as it satisfies all the conditions when compared to that of the other 3 stages. The following observations were made in the static analysis plots for stress, displacement, strain and factor of safety at the fourth stage. a) In stress plot the regions with high stress value were analysed and seemed to be safe. b) In displacement plot the motor hold seem to have high deflection so it has to be optimized and corrected. c) In strain plot the transverse drive rod have a high value at a point where the motor hold is sliding through thus the transverse drive is also to be optimized. d) In the analysis of the overall factor of safety of the portable friction stir welding machine show that all the parts are safe expect the transverse drive with a factor of safety of 1.431e-001 which is safe because the applied load is double the required load. The Structural static analysis also was successfully completed using Solid Works by applying 2 tonne load and the results of various parameters like stress, displacement, strain are plotted and tabulated. 5. References [1] Gurunath Shindea, Sameer Gajghate , Dr.P.S.Dabeer , Dr.C.Y. Seemikeri , Low Cost Friction Stir Welding: A Review, Materials Today: Proceedings 4 (2017) pp 8901–8910 [2] W.M. Thomas, E.D. Nicholas, J.C. Needham, M.G. Much, P. Temple-Smith, C.J. Dawas, Friction stir butt welding, GB Patent No. 9125978.8, International patent application No. PCT/GB92/02203,(1991). [3] L.V. Kamble, S.N. Soman, P.K. Brahmankar, Understanding the Fixture Design for friction stir welding research experiments, Materials Today: Proceedings 4 (2017) pp 1277–1284 [4] Fujii, H., Cui, L., Maeda, M., Nogi, K. Effect of tool shape on mechanical properties and microstructure of friction stir welded aluminum alloys., Materials Science and Engineering (2006) A419, 25–31.
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