DESIGN & ANALYSIS OF CONNECTING ROD OF FORMING AND CUTTING DIE PILLAR STATION OF VACUUM FORMING MACHINE

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2 Research Paper ISSN Vol. 3, No. 3, July, IJMERR. All Rights Reserved DESIGN & ANALYSIS OF CONNECTING ROD OF FORMING AND CUTTING DIE PILLAR STATION OF VACUUM FORMING MACHINE C P Gaikwad 1 * and S D Kalpande 2 *Corresponding Author: C P Gaikwad chetangaikwad99@gmail.com The objective of this work is to design and analyze the performance of connecting rod, through a simple experimental model of Forming and Cutting Die Station of Vacuum Forming Machine. A connecting rod is a machine member subjected to alternating direct compressive and tensile forces, compressive forces are generally more in connecting rods so it is considered for its prime safety. A parametric mathematical model of connecting rod is modeled using Pro-E Wildfire 4.0 Software and its Static Structural Analysis is carried on Ansys v-11.0 Workbench. FEA of connecting rod is done using C50 as its base material to determine its von-mises stress, Max shear Stress, Total Deformation and Alternating stress to cycles graph. Also the Stiffness of connecting rod is calculated. Keywords: Connecting rod, Vaccum forming, Ansys, FEA, Compressive, Design INTRODUCTION In its simplest form the Vacuum forming process consists essentially of inserting a thermoplastic sheet in a cold state into the forming clamp area, heating it to the desired temperature either with just a surface heater or with twin heaters and then raising a mould from below. The trapped air is evacuated with the assistance of a vacuum system and once cooled a reverse air supply is activated to release the plastic part from the mould. (5) The connecting rod is used in thermoforming machine is to transmit forces and motion from motor through gearbox and crankshaft to bottom plate of the machine to have its motion to carry out its process of forming cum cutting off plastic sheets. EXPERIMENTAL SETUP Forming and Cutting Die Pillar Station Vaccum forming machine is used to form the plastic parts to desired shape. In this Figure1 there is a top and bottom plate within which the forming cum cutting die is placed between the two plates. The Vacuum System is used to form the plastic by means of high vacuum 1 Mechanical Engineering Department, MET Institute of Engineering & Research, Nasik, India. 2 Mechanical Engineering, MET Institute of Engineering & Research, Nasik, India. 103

3 pressure as well as high pressure air from top also for equal distribution of wall thickness of plastic. Before this station there is heating station to preheat the sheet which is to be formed and after heating station this forming cum cutting station is placed.figure:1 show the Experimental setup of forming cum cutting die pillar station. The various parts of the Die pillar stations are as follows: 1) Top plate, 2) Bottom plate, 3) Shaft, 4) Crank, 5) Connecting rod, 6) Bearings, 7) Die Pillars, 8) Gear box and 9) Motor. Out of all these parts we are designing the Connecting rod which is an important part in transmitting motion Table 1: Vacuum Forming Machine Specifications Machine Specifications Die Size Cutting Force No: of cycles Forming Process Heaters capacity Material to be Formed & Cut Thickness Range 1010 mm x 300 mm 50 tons = KN 40 cycles/min Vaccum forming 55 KW PVC,PET,HIPS,ABS mm The I- cross-section of connecting rod is shown Figure 2: Standard Dimensions of I-Section (3) DESIGN OF CONNECTING ROD A connecting rod is a machine member which is subjected to alternating direct compressive and tensile forces. Since the compressive force are much higher than tensile forces. Therefore, the crossection of connecting rod is designed as a strut and Euler s Formula is used. (R S Khurmi and J K Gupta, 2005). Figure 1: Forming & Cutting Die Pillar Station of Vacuum Forming Machine Let, B= Width of I-section, mm. H= Height of I-section, mm. A= Area of I-section, mm 2. k XX = Radius of gyration of section about X-axis. FOS = Factor of Safety. r = Length of Crank, mm. l = Length of connecting rod, mm. W B = Buckling Load, N. A = Area of Section, mm 2. A = 2 (4t x t) = 11 t 2, mm

4 Moment of Inertia about X-X, I X-X = BH 3 12 = 419 t 4 mm 4 12 Moment of Inertia about Y-Y, I Y-Y = HB 3 12 = 131 t 4 12 Connecting rod is considered like both ends hinged for buckling about X-axis and Both ends fixed for buckling about Y-axis Connecting rod should be equally strong in buckling about both axis. In order to have connecting rod equally strong in both axis. It should satisfy the following conditions, I X-X = 4 I Y-Y. In actual practice, I X-X is kept slightly less than 4 I Y-Y. It is usually taken between 3 and 3.5 and connecting rod is designed for buckling about I X-X. I X-X = 3.2 I Y-Y Since the ratio is in between 3 to 3.5, therefore the I-section chosen is quite satisfactory. Basically the force acting is KN on each connecting rod. Generally Factor of safety is taken between 5 and 6. So Selected Factor of Safety is 5. Therefore, Bucking Load = F x FOS = x 5 = KN Radius of gyration of section about X-axis k XX = I X-X /A = 1.78 t. Length of Crank, r = Die opening size /2 = 164 / 2 = 82 mm Length of Connecting rod, l = 500 mm. According to Rankine s Formula W B (about X-axis) = c.a 1 + a ( l/k xx ) x 10 3 = 350 x11 t x 10 3 = 11 t (1/7500) (600/ 1.78 t) 2 t t t = 0 t 2 = ± ((348.36) 2 + (4 x ) 2 t 2 = or (Taking +ve sign) t = 19 mm Thus Dimensions of connecting rod are Thickness of flange and web of section = 19 mm Width of the section, B = 4 t = 76 mm Height of the section, H = 5 t = 95 mm Depth near Big End, H 1 = 1.25 H = 119 mm Depth near the small end, H 2 = 0.9 H = 86 mm Parameters Table 2: Parameters Values Length of connecting rod Outer Dia. of Crank end Inner Dia. of Crank end Outer Dia. of Small end Inner Dia. of Small end Values 600 mm 280 mm 240 mm 150 mm 120 mm 105

METHODOLOGY Modeling of Connecting Rod Connecting rod is modeled on Pro-E Wildfire 4.0 software. The Mathematical Model is imported to ansys software is shown in Figure 3.

5 METHODOLOGY Modeling of Connecting Rod Connecting rod is modeled on Pro-E Wildfire 4.0 software. The Mathematical Model is imported to ansys software is shown in Figure 3. Steps to Model Connecting Rod Open Pro-E Wildfire 4.0 software enter into sketching plane section draw the sketch of Connecting rod with help of various sketching commands and 3D modeling commands in modeling the connecting rod. Once the Mathematical model is prepared and exported to iges format and imported to Ansys v 11.0 software for analysis purpose. Steps Involved in FEA Meshing Basically in Ansys v 11.0 software it automatically selects the type of mesh. In this case Tetrahedral element is selected for its analysis. For analysis the element size selected is 3mm with fine mesh. Figure 4: Meshed Mathematical Model of Connecting Rod Figure 3: Mathematical Model of Connecting Rod Statistics Nodes Elements Properties The material properties given in below table are entered in Engineering Data with name as Structural Steel. Finite Element Analysis In this study, the connecting rod is designed for compressive yield strength.in this study of FEA of connecting rod the allowable compressive yield strength is compared with Ansys Von- Mises stress. Basically the analysis is in Static Structural Analysis module. Table 3: Material Properties Material Properties of C50 Young s Modulus 2.1e+005 MPa Poisson s Ratio 0.3 Density 7.85e-006 kg/mm³ Yield Strength 350 MPa Tensile Ultimate Strength 700 MPa 106

Constraint Two constraints are used in this analysis Displacement Constraint: In both the FE models one end, i.e., the crank end of the connecting rod was fixed and the other end was not allowed to rotate about y and x- axis but free to rotate about z-axis.

6 Constraint Two constraints are used in this analysis Displacement Constraint: In both the FE models one end, i.e., the crank end of the connecting rod was fixed and the other end was not allowed to rotate about y and x- axis but free to rotate about z-axis. Also the pin end or the small end is allowed to move freely in transnational direction (in x-y-z) Load Constraint: In the FE models no external force is acting on the big end but on the small end KN of compressive force is applied in the y-direction whereas there is no external force in the x and z direction. (Ramanpreet Singh, 2013). Results Once the individual attachment is done for viewing different results select each attachment for viewing individual results. RESULTS AND DISCUSSION Figure 6: Von-mises Stress for Connecting Rod Figure 5: Loads & Boundary Conditions for Connecting Rod (4) Figure 7: Maximum Shear Stress for Crankshaft Figure 8: Deformation of Connecting Rod Analysis When all loads and displacement are applied analysis would be last step. Select the option called Solve. The software starts analyzing automatically and finally solves the problem. 107

7 Table 4: Material Properties Yield Strength 350 N/mm 2 Theoretical FOS 5 Allowable Stress 70 N/mm 2 Ansys Stress N/mm 2 Working FOS 5.5 The allowable stress is 70 N/mm 2 and FOS is 5. But the Ansys results in Von-Mises stress is N/mm 2 and Working FOS is 5.5. From Analysis we can conform that the design of connecting rod is safe. While from deformation analysis we can see that deformation is maximum at small end and also stress is maximum at small end. Figure 9: Alternating Stresses Table 5 shows the graph of Alternating Stress v/s cycles indicate the life of connecting rod. It shows that connecting rod will have a life span of about 3.16 e+6 cycles. Result for stiffness of connecting rod is as follows Weight of connecting rod : kg Deformation : mm Stiffness = Weight/ Deformation, (3) = Kg/mm CONCLUSION The working factor of safety is nearer to theoretical factor of safety.the Ansys Vonmisses stress is N/mm 2 is nearer to allowable stress value. Hence it seems design of connecting rod is safe. Connecting rod will have a life span of about 3.16 e+6 cycles. And stiffness is about Kg/mm. REFERENCES 1. B Anusha (2013), Comparison of Materials for Two Wheeler Connecting Rod Using Ansys, IJETT, Vol. 4, No. 9. Table 5: Alternating Stress v/s Cycles Cycles Alternating Stress MPa e e e FormechVacuumGuide.pdf 3. K Sudershn Kumar (2012), Modelling and Analysis of Two Wheeler Connecting Rod, IJMER, Vol. 2, No R S Khurmi and J K Gupta (2005), A Textbook of Machine Design, Eurasia Publishing House.. 5. Ramanpreet Singh (2013), Stress Analysis of Orthotropic and Isotropic Connecting Rod Using Finite Element Method, IJMERR, Vol. 2, No

Analysis of Crank End of Connecting Rod using Finite Element Method

Analysis of Crank End of Connecting Rod using Finite Element Method Mohammad Umair Zaki Faculty of Mechanical Engineering Noida International University Greater Noida, India e-mail-umairzaki@yahoo.com