Composite Cycle Frame Manufacturing Methods Project

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ACKNOWLEDGEMENT

I would like to take this chance for thanking my research facilitator, friends & family for support they provided & their belief in me as well as guidance they provided without which I would have never been able to do this research.



DECLARATION

I, (), would like to declare that all contents included in this thesis/dissertation stand for my individual work without any aid, & this thesis/dissertation has not been submitted for any examination at academic as well as professional level previously. It is also representing my very own views & not essentially which are associated with university.

Signature:

ACKNOWLEDGEMENT2

DECLARATION3

INTRODUCTION6

Problem definitions8

Bicycle frame and composite laminates8

Three testing methods11

STRUCTURE REQUIREMENTS14

The Bicycle Frame14

Bicycle Frame Design15

The manufacture of the Bicycle Fram18

The welded frame18

Frames with lugged joints19

Carbon fibre frames with lugged joints19

Single piece or monocoque carbon fibre frames20

Painting the bicycle frame22

MANUFACTURING PROCESS24

Bladder & Foam Core Molding24

Resin Transfer (RTM) & Filament Wound construction26

Closed molding27

Finishing and testing27

Whether these are done-in-house or outsourced28

Machining Type28

ASSEMBLY30

Materials30

Top tube30

Head tube31

Down tube31

Seat tube31

Seat stays31

Chain stays31

Joining frame tubes of carbon fiber bicycle32

Lug construction33

Fillet brazing33

TIG-Welding33

Bonding construction34

Monocoque molding (one-piece construction)34

Parts to construct the Assembly -'in house' or 'outsourced' or 'bought34

Construction and assembly35

Design35

Analysis36

Tooling36

Materials37

Layup process37

Secondary operations37

Finishing38

COSTING AND CALCULATION39

Factors to be taken into consideration40

Process of Manufacturing the Bicycle Frame41

Costing42

Analysis of costs44

Costing the components47

Fixed production costs48

Other costs48

Analysis48

SELECTION OF LOGISTICAL50

The Logistics of the Carbon-Fibre Bike's Frame50

Demand forecasting/planning50

Logistics communications53

Material handling54

Order processing55

Packaging56

Packing57

Warehousing packaging57

Parts and service support58

Transportation58

EVALUATION OF QUALITY AND CORROSION60

The options available for corrosion resistance for the components60

Evaluation of quality of assurance throughout the cycle frame project63

PAINTING70

RECOMMENDATIONS73

Manufacturing and product development73

Frame design74

Process design75

Material lay-up76

Future developments77

CONCLUSION78

REFERENCES80

INTRODUCTION

Composite materials which are composed of reinforced fibers and plastics matrix have high strength-to-weight and stiffness-to-weight ratios. They have unique advantages over monolithic materials, such as high strength, high stiffness, long fatigue life, low density, corrosion resistance, wear resistance, and environmental stability. Due to above characteristics, the laminated fiber-reinforced composite materials such as carbon/epoxy or glass/polyester composites are widely applied in aircraft, aerospace, military, automotive, marine, and sports structures.

The bicycles are popular sports equipments or traffic tools. The frame of the bicycle is the main structure to support the external loads. Traditional materials of the bicycle frame are the steel or aluminum alloy. For the purpose of reducing weight, the carbon/epoxy composite materials are now widely used to make the bicycle frames. An example of the carbon/epoxy bicycle frame only weights 1.36 kg, which is much less than the 5 kg weight of the corresponding steel frame.

In the design process of the bicycle, the structural analysis of the frame or other parts is a very important stage. With the aid of theoretical or numerical calculations, the strength and stiffness of the bicycle structures can be predicted and modified to the optimal design before the manufacture of the prototype and commercial products. The finite element method is one of the numerical calculations applied in various physical problems. It usually plays a major role to calculate the stress and deformation of the structures.

In 1986, the finite element method was applied in the design of the steel and aluminum bicycle ...