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Nathaniel Jennings
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Research Paper DESIGN EVALUATION USING FINITE ELEMENT ANALYSIS FOR MACHINE FRAME TO MEET COMPLIANCE FOR STRUCTURAL INTEGRITY 1 Swapnil Killedar, 2 Prof. Sanjay Deodas, 3 Swapnil S.

1 Research Paper DESIGN EVALUATION USING FINITE ELEMENT ANALYSIS FOR MACHINE FRAME TO MEET COMPLIANCE FOR STRUCTURAL INTEGRITY 1 Swapnil Killedar, 2 Prof. Sanjay Deodas, 3 Swapnil S. Kulkarni Address for Correspondence 1 M.E. (Design) 2 nd yr, 2 P.G. Coordinator, Heat & Power, D.Y. Patil College of Engineering, Akurdi, Pune 3 Director-Able Technologies India Pvt. Ltd., Pune, India ABSTRACT: Machine Frames are normally cast or fabricated with the new trend pointing to assembly using extrusions with fasteners. For most production applications of machine tool structures, (gray cast iron) metal castings remain the primary choice because of cost, ease of sourcing, good damping with relatively high strength, good machinability and well-established and consistently achievable manufacturing and processing requirements. However, fabrications are normally the preferred choice for low volume production of large structures, Although the more robust construction for SPM prefers fabricated sections of square tubes. For this work, the base Frame of `Pressing SPM is being designed as a fabricated structure followed by Finite Element Modeling and Analysis to verify its strength under the given working conditions. The SPM is modeled using commercial software and all the specification was accordingly followed the relevant drawing standard. The geometry of machine is modeled using competent software CATIA V5 R18 software. The FE model is prepared with the help of hypermesh software while doing so square tubes are mesh with the 2D Quad element &solid partis mesh with Second order 10 noded tetra elements. The attempt is to identify alternatives i.e. Diagonal, Parabolic, Trapezoidal, Cast machine etc. for sufficing the task while recommending the best solution to the given problem. Offering structural strength while incorporating simplicity in design and process of development shall be the objective of the work. The thesis would be validated with analogy for the raw material test piece to be tested in a laboratory. A three point bending test on test specimen is done on UTM and result is compared with FEA result of the specimen. INTRODUCTION: For most production applications of machine tool structures, (gray cast iron) metal castings remain the primary choice because of cost, ease of sourcing, good damping with relatively high strength, good machinability and well-established and consistently achievable manufacturing and processing requirements. However, fabrications are normally the preferred choice for low volume production of large structures, due mainly to the high up-front molding costs and the difficulties in process control inherent in very large castings. On the other hand, with increasing emphasis on high speed machining, hard turning, and better and consistent machining accuracies, structural rigidity, thermal stability and vibration damping are becoming major design considerations for alternative solutions The machine tool industry is required to evolve variants that are powerful, efficient, and accurate while being cheaper and technologically superior over its predecessors. This poses a challenge to the Design Engineer while he tries to address the problems while maintaining the ground guidelines of the entire machine tool and thus influence its characteristics and also the performance. At present, the existing base of the machine is being reviewed in the context of its suitability for the given range of applications/variants. Besides, compliance to any recent corporate or regulatory norms need to be reviewed. In the broad sense, design of structure consists of two parts. The first parts deals with determination of forces at any point(or) of given structure and second part deals with the selection and design of suitable section to resist these forces so that the stresses and formation developed in the structure due to these forces are within permissible limits. The first part is termed as structural analysis and the second as proportioning or dimensioning of members. The term structural implies not only civil engineering structure such as bridges and buildings, but also naval, aeronautical mechanical structures such as ship hulls, aircraft bodies etc. Before any analysis, we shall require the entire details of the structure, loading and functional properties. To proportion a structure, we must first know how it will behave under loading. Therefore, process of analysis and design form integral part of design. Therefore, the intended purpose of any analysis is to know how the structure responds to a particular loading and thereby evaluate stresses and deformation. The purpose of structure analysis is to determine the reaction, internal forces such as axial, shear, bending and torsional deformations at any point of given structure caused by the applied loads and forces. LITERATURE REVIEW: B. Li, J. Hong, Z. Wang, W. Wu, Y. Chen. [2] This paper attempts to develop a simple and practical procedure for the optimal design of machine tool bed. In this research, a simplified model is first defined to characterize the bed structure. The load bearing topology of the bed structure is then identified to represent the optimal layout of the inner stiffener plates. Subsequently, detailed sizing optimization is conducted by using a novel criterion which describes the best solution in terms of weight distribution of both the outer supporting panels and inner stiffener plates. Finally, calculation results are elaborated to demonstrate the effectiveness of the proposed method. David Thévenet, Mohamad Fathi Ghanameh, AbderrahimZeghloul. [3] The tubular joints, frequently employed in the offshore industry, are submitted to stresses resulting from elementary loadings: tension/compression, in-plane bending and out-of-plane bending. This work concerns the analysis of the recommendations commonly used for the fatigue design of welded joints submitted to combined loadings. Particularly, it deals with the fatigue behaviour of T-joints submitted to deviatedbending: first, a finite element analysis was developed and a post-processing based on the structural stress approach, as proposed by the International Institute of Welding (IIW). Then,

2 fatigue tests were conducted on T-joints submitted to deviated-bending. Comparisons between experimental and numerical results showed that this kind of recommendations is not systematically conservative. Thus, an alternative approach based on structural stresses and taking into account the multiaxial stress state in the weld toe was developed in order to complete the recommendations for the fatigue design of tubular welded joints. Daisuke kono, Takahiro Inagaki et al [4] proposes a 3D stiffness model of a machine tool support using contact stiffness. The stiffness in each direction is assumed to be determined by the contact stiffness at the interfaces and the bulk stiffnesses of the supports and the floor. The contact stiffness model proposed by Shimizu et al. is expanded to determine the contact stiffness in the normal and tangential directions of an interface. In the proposed model, the contact stiffness is obtained by multiplying the unit contact stiffness by the real contact area. The contact stiffness of concrete is experimentally investigated to estimate the stiffness between machine tool supports and the floor, and it was observed to be the primary determinant of the stiffness of interfaces between metal and concrete. Moreover, the unit contact stiffness of concrete is discovered to be less than 1/10 of those of the metals that were used for the study. The natural frequency and vibration mode shape of a model machine tool bed are also experimentally measured and used to verify the proposed stiffness model. The comparison of the results obtained from the two procedures shows that the natural frequency and vibration mode shape of a machine tool bed can be predicted using the proposed stiffness model. Yanjun Xiao et al. [5] the author mainly introduces the solid modeling and assembly simulation of the shear sheet machine based on PRO/E. A design platform used for entity parametric modeling and assembly of the shear-sheet machine is introduced based on Pro/Engineer software. Using parametric modeling, researchers established each parts of shearsheet machine. Using module assembly of Pro/Engineer software and setting constraints, author finished the mechanism general assembly and simulation analysis. The result shows that assembly and simulation analysis can shorten the design and manufacturing cycles of new products, and reduce costs in research. M. Dundu [6] the author investigates the behaviors of base connections, fabricated from cold-formed channels and hot-rolled angle cleats. This investigation is part of an extensive research to develop portal s made out of single cold-formed steel channels. The use of bolted angle cleats allows for a simple connection to be developed, which can result in significant cost savings within the steel construction industry. Stiffer angle cleats are used to prevent premature failing of the base connections. The base connections are subjected to four loading configurations and these are dependent on the eccentricity of the load. In base connections where cold-formed angle cleats were used, failure of the bases was largely caused by premature deformation of the angle cleats. Base connections with hot-rolled angle cleats were so stiff that failure occurred in the column channels instead of the angle cleats. A significant amount of bearing distortion was observed in the heavily loaded flange. A simple formula is suggested to design these bases. T Katayama et al. [7] The author in this paper trying to construct the CAE system to predict the stiffness of structure in SMC compression moulding. Sheet moulding compound (SMC) product have some ribs to improve the stiffness of structure, so because of the ribs, fibre distribution and orientation in rib change, and the expected stiffness of product cannot be obtained. In these cases, while it is needed to change die design, it cost greatly to do so. Therefore CAE system to improve the efficiency of the die design is needed. By the way, stiffness of SMC product in compression moulding is influenced by the moulding condition, especially material flow. However material flow of SMC is complex and unsteady. In ribs, it is difficult to predict material flow, fibre distribution, fibre orientation and so on. Therefore it is useful to apply the database that can express these factors simply. In this paper author investigated the mechanical properties in the rib parts of SMC product. From the result, Author constructed the method of estimating the Young's modulus in the rib part in consideration of heterogeneity as fibre orientation, fibre distribution and resin rich part. Consequently, in predicting the Young's modulus in the rib part author get good agreement with the values by experiment and the system. METHODOLOGY: Figure 1: Basic steps FEA OF EXISTING MACHINE FRAME [5] Creation of Geometry The SPM is modeled using commercial software and all the specification was accordingly followed the relevant drawing standard. The table geometry was shown in figure 2The geometry of machine is modeled using competent software CATIA V5 R18 software. Figure 2: CAD Model Existing machine Meshing details: [1] Mesh generation is a process of dividing the structure continuum into a number of discrete parts or finite elements. The finer mesh, the better the results but

made, 2-D Quad and Second order 10 noded tetra elements was used

Material properties: The following are the material properties of

Analysis: Loading and Boundary conditions: The next step after

A Static load of 50000 N is applied gradually over the entire

element (i.e. Rigid beam element) Figure 6: Maximum displacement

boundary condition for Existing Static Analysis Displacement

Variant 4: Casting Machine Frame:[5] Figure 4: Displacement

model for cast machine Meshing details: Figure 5: Stress analysis

3 longer the analysis time. Therefore compromise between accuracy & solution speed is usually made, 2-D Quad and Second order 10 noded tetra elements was used to create mesh model. Material properties: The following are the material properties of given SPM Table 1: Material Properties for Existing Displacement Analysis: Loading and Boundary conditions: The next step after meshing is applying loading and boundary condition. A Static load of N is applied gradually over the entire machine bed through centre of gravity of entire machine by RBE2 element (i.e. Rigid beam element) Figure 6: Maximum displacement for Diagonal machine Stress analysis: Figure 3: Loading and boundary condition for Existing Static Analysis Displacement Analysis: Figure7: Maximum Stress Analysis of diagonal Variant Variant 4: Casting Machine Frame:[5] Figure 4: Displacement analysis lot for Existing machine Stress Analysis : Figure 8: CAD model for cast machine Meshing details: Figure 5: Stress analysis for Existing machine Variant 1: Diagonal Machine Frame:[5] Geometry Creation: The geometry of machine is modeled using competent software CATIA V5 R18 software Figure 9: Meshing interface for cast machine

The geometry is mesh with Second order 10 noded tetra element was used to create mesh model. Material properties: Table 2: Material properties of cast machine reading is desired.

Static Analysis: Displacement analysis: Figure 13: Displacement Analysis of test specimen: Figure 10: Displacement analysis for Cast machine Stress analysis Figure 14: Stress Analysis of test

specification shall be manufactured for testing. The input conditions shall be recreated in the lab while prototype is being tested for performance.

The test report is procured by sponsoring company.

displacement upto 0.08 and maximum stress is 242.43 MPa Among the different alternatives suggested the variant 4 i.e. casting variant has lowest stress value among all geometries i.e.62.

4 The geometry is mesh with Second order 10 noded tetra element was used to create mesh model. Material properties: Table 2: Material properties of cast machine reading is desired. Typically depending on type of test and the application, an error margin or about 5-20 % could be considered close towards validating the proposed design Displacement Analysis of test specimen: Static Analysis: Displacement analysis: Figure 13: Displacement Analysis of test specimen: Figure 10: Displacement analysis for Cast machine Stress analysis Figure 14: Stress Analysis of test specimen: RESULT: Table 3: Comparison of Maximum displacement in all cases Figure 11: Stress analysis for Cast machine Experimentation & Validation A prototype, identical in feature and specification shall be manufactured for testing. The input conditions shall be recreated in the lab while prototype is being tested for performance. The loading and boundary condition would match the actual working condition. Three Points bending test is performed under the UTM with suitable fixture for the square tube. The test report is procured by sponsoring company. Figure 12: Three point bending test of square tube test piece under UTM VALIDATION The test report for square tube prototype would form basis for verifying the results with the analytical method of analysis. For validating the design of machine, a good match of the corresponding Table 4: Comparison Maximum stresses in all cases From the analysis it is found that the existing machine has maximum displacement upto 0.08 and maximum stress is MPa Among the different alternatives suggested the variant 4 i.e. casting variant has lowest stress value among all geometries i.e MPa and displacement is 0.14 As there is more cost involve in casting process and as compare to fabrication it is much complicated we suggest fabricated structure to be selected as a best possible solution As there is more suitability for sponsoring company for fabricated structure instead of casting we suggest variant 1 i.e. Diagonal machine as a best possible solution. Maximum stress in this case MPa which is much lower than calculated safe stress i.e MPa FUTURE SCOPE: Angles and c-channel should be used instead of square tube if possible, because it cost less and their availability is easy.

5 Instead of changing geometry one should change the thickness of square tube and analyze. If possible, then casting variant should be used as references model for cast machine. Different optimization technique should be used to minimize stress such as Topology, Topography, and Shape optimization. CONCLUSION: The results obtained are quite favorable which was expected. Finite element analysis is effectively utilized for addressing the conceptualization and formulation for the design stages. The stresses derived during the analysis phase normally indicate the potential solution. The iterations are carried out in the analytical phase which yields the suitable values for design parameter. The suggested variant of cast machine and diagonal machine gives satisfactory results. Out of which diagonal variant is selected as a optimum design solution by sponsoring company because of their suitability with ease of production, less manufacturing cost as compared to casting machine. The diagonal variant has low maximum stresses as compare to existing machine and it is much lower than yield stress so there life is much increased. REFERENCES: 1. Nitin S Gokhale Practical Finite Element Analysis Finite to Infinite publication, First Edition(2007),pp J. Hong, Z. Wang, W. Wu, Y. Chen, Optimal Design of Machine Tool Bed by Load Bearing Topology Identification with Weight Distribution Criterion, 45th CIRP Conference on Manufacturing Systems, Procedia CIRP 3,( 2012 ), pp David Thévenet, MohamadFathiGhanameh, AbderrahimZeghloul, Fatigue strength assessment of tubular welded joints by an alternative structural stress approach, International Journal of Fatigue 51,(2013), pp Daisuke Kono, Takahiro Inagaki, Atsushi Matsubara, IwaoYamaji, Stiffness model of machine tool supports using contact stiffness, Journal of Precision Engineering 37, (2013), pp Yanjun Xiaoa, Jinling Zhanga, Baoshuang Yaoa, Yuming Guana, Assembly and Simulation analysis of Shear-sheet Machine Based on Pro/E, International Workshop on Automobile, Power and Energy Engineering, Procedia Engineering 16, ( 2011 ),pp M. Dundu, Base connections of single cold-formed steel portal s, Journal of Constructional Steel Research 78, (2012), pp T. Katayama, M. Shinoharo, M. hakotani, A. Kitade, D.kono Development of CAE for predicting stiffness of SMC structure estimation of Young s modulus in rib part. Journal of material processing technology 119, (2001), pp

FEA and Topology Optimization of an Engine Mounting Bracket

FEA and Topology Optimization of an Engine Mounting Bracket International Journal of Current Engineering and Technology E-ISSN 2277 4106, P-ISSN 2347 5161 2016 INPRESSCO, All Rights Reserved Available at http://inpressco.com/category/ijcet Research Article Sanket