ABSTRACT

Knuckle joint is one of the important components of vehicle which is used to

transmit axial tensile force. In this project static analysis of knuckle joint is done.

A knuckle joint is designed for increasing the capacity to withstand load and the

maximum bending stress of the pin. The aim of the present project is to study the

stresses in Knuckle joint using analytical method. It is proposed that instead of

mild steel pin high strength high modulus Molybdenum pin can be used for further

enhancing the capacity to withstand higher loads. The knuckle joint proposed work

is to study the behavior of pin for an applied force of 150 KN. The diameter of the

pin is proposed to be around 25 mm and the factor of safety of 2. The material of

the knuckle joint is considered as Molybdenum in order to do the stress analysis.

CAD model of knuckle is prepared in CATIA. Static analysis is done in ANSYS

by constraining the knuckle and for applied loads, the stress contour, displacement

contour, strain energy contour are obtained. These Finite Element Analysis results

are verified by comparing with analytical calculations.

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TABLE OF CONTENT

CHAPTER NO. TITLE PAGE NO.

ABSTRACT I

LIST OF TABLES IV

LIST OF FIGURES V

LIST OF SYMBOLS VI

1. INTRODUCTION 1

2. LITERATURE SURVEY 5

3. ENGINEERING DESIGN 7

3.1 Dimensions of knuckle joint 7

3.2 Methods of Failure of Knuckle Joint 9

4. MATERIAL SELECTION 13

4.1 Introduction 13

4.2 Chemical Composition 13

4.3 Physical Properties 13

4.4 Mechanical Properties 14

5. DESIGN CALCULATIONS 15

5.1 Failure of the knuckle pin in shear 15

5.2 Failure of the rod end in tension 17

5.3 Failure of the rod end in shearing 17

5.4 Failure of the rod end in crushing 18

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5.5 Failure of the forked end in tension 18

5.6 Failure of the forked end in shear 19

5.7 Failure of the forked end in crushing 19

6. MODELLING 20

6.1 Introduction 20

6.2 Modelling 22

6.3 Drafting 23

6.4 CATIA model 24

7. RESULT AND ANALYSIS 27

7.1 Analysis tool 27

7.2 Meshing method 27

7.3 Theoretical calculation 31

7.3.1 Normal stress in x-x direction 31

7.3.2 Maximum principal stress 31

7.3.3 Minimum principal stress 32

7.3.4 Maximum shear stress 32

7.3.5 Von mises theory 33

7.4 Comparison of results 33

8. CONCLUSION 34

9. REFERENCES 35

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LIST OF TABLES

TABLE NO. TITLE PAGE NO.

4.1 Chemical Composition 13

4.2 Physical Properties 13

4.3 Mechanical Properties 14

7.1 Stresses and Deformation results of

Molybdenum 31

7.2 Comparison of results 33

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LIST OF FIGURES

FIGURE NO. TITLE PAGE NO.

1.1 Knuckle joint 2

3.2 A typical knuckle joint 7

6.1 Drafting of knuckle joint 23

6.2 Fork model 24

6.3 Pin model 24

6.4 Eye model 25

6.5 Collar model 25

6.6 Tapper pin model 26

6.7 Assemble of knuckle joint 26

7.1 Meshed view of knuckle joint 28

7.2 Knuckle joint with boundary condition 28

7.3 von-mises stress 29

7.4 Maximum principal stress 29

7.5 Shear stress 30

7.6 Total deflection 30

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LIST OF SYMBOLS

P = Tensile load acting on the rod

A = Area of the pin

d = Diameter of the rod

d1 = Diameter of the pin

d2 = Outer diameter of eye

d3 = Diameter of knuckle pin head and collar

t = Thickness of single eye

t1 = Thickness of fork

t2 = Thickness of pin head

σt, = Tensile stress

τs = Shear stress

σc = crushing stress

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