DESIGN AND FABRICATION OF WELDING FIXTURE

FOR I.C.F BOGIE FRAME

A PROJECT REPORT

Submitted by

R.PERUMAL 41407114030

N.R.SARAVANAN 41407114038

S.SUBBURAJ 41407114045

N.ASHWIN 41407114007

In partial fulfillment for the award of the degree

Of

BACHELOR OF ENGINEERING

In

MECHANICAL ENGINEERING

PRINCE SHRI VENKATESHWARA PADMAVATHY ENGINEERING COLLEGE

PONMAR, CHENNAI – 48

ANNA UNIVERSITY :: CHENNAI 600 025

APRIL 2011

ANNA UNIVERSITY : CHENNAI 600 025

BONAFIDE CERTIFICATE

Certified that this project report “DESIGN AND FABRICATION OF

WELDING FIXTURE FOR I.C.F BOGIE FRAME ” is the bonafide work of

“ R.PERUMAL (41407114030) ” who carried out the project work under my

supervision .

SIGNATURE SIGNATURE

Mr.B.Brucelee,M.E. Mr.A.Baskar,M.E.,MBA,(PhD)

ASSISTANT PROFESSOR ASSISTANT PROFESSOR

HEAD OF THE DEPARTMENT SUPERVISOR

DEPARTMENT OF MECHANICAL DEPARTMENT OF MECHANICAL

ENGINEERING ENGINEERING

PRINCE SHRI VENKATESHWARA PRINCE SHRI VENKATESHWARA

PADAMAVATHY ENGINEERING PADMAVATHY ENGINEERING

COLLEGE COLLEGE

CHENNAI - 48 CHENNAI - 48

SUBMITTED FOR PROJECT VIVA HELD ON _________________

INTERNAL EXAMINER EXTERNAL EXAMINER

ACKNOWLEDGEMENT

We express our deep gratitude to our honorable chairman

Dr.K.VASUDEVAN M.A.B.Ed.PhD., for rendering the technical staffs in

completing this project.

We convey our sincere gratitude to honorable principal

Dr.T.SOUNDERARAJAN M.Tech.PhD., for his moral support .

Special thanks to our project coordinator Mr.B.BRUCELEE, M.E., for

the help and support rendered to us .

We sincerely our project guide Mr.A.BASKAR,M.E.,MBA,(PhD) for

his constant encouragement and technical guidance . His inspirational and moral

support have been inestimable in increasing our knowledge .

We also express our deep gratitude to all other faculty members for their

moral support rendered to us.

Our sincere thanks to Mr.P.ETRAJ , Chief Instructor , Locoworks ,

for giving us constant encouragement and perceptive advice. He has been a

constant source of inspiration.

My special gratitude for Mr.P.R.SATHYAPAUL , Senior Section

engineer , Coach Repair Shop, Locoworks , for having guided us in every sense ,

especially in obtaining various results in the design process.

We would like to express our sincere gratitude to family members for

their loving support and encouragement. Many thanks to our friends for the support

and considerations rendered to us while doing project.

TABLE OF CONTENTS

CHAPTER NO. TITLE PAGE NO.

ABSTRACT I

LIST OF FIGURES II

LIST OF SYMBOLS III

LIST OF TABLES IV

1. INTRODUCTION 1

2. LITERATURE REVIEW 2

2.1 THE BOGIE 2

2.1.1 Details About Bogie 2

2.1.2 Brief Description of Bogies 3

2.1.3 Attention of Bogie Components 4

2.2 WELDING DETAILS 5

2.2.1 Flux Cored Arc Welding 5

2.2.2 Process variables 7

2.2.3 Advantages 7

2.2.4 Disadvantages 8

2.3 BOGIE FRAME 8

2.3.1 Parts of Bogie Frame 9

2.3.2 Parts to be Welded 9

2.3.3 Welding by Existing Method 10

2.3.4 Disadvantages of Existing method 12

3. NEED OF PROJECT WORK 13

3.1 Ultimate Advantage 13

3.2 Scope of Project Work 14

3.2.1 Problem Analysis 14

3.2.2 Limitation 15

3.3 THE FIXTURE 15

3.3.1 Difference between a Fixture & a jig 16

3.3.2 Advantage of Fixture 16

3.3.3 Design Principles of fixtures 16

3.4 Materials used in Fixture 19

4. FABRICATION OF ROTARY FIXTURE 22

4.1 PROPOSED ROTARY FIXTURE 22

4.2 PARTS DESCRIPTION 22

4.3 FABRICATION PROCEDURE 24

4.4 ADVANTAGES OF PROPOSED METHOD 25

5. DESIGN CALCULATION 26

5.1 BILL OF MATERIALS 27

5.2 SPECIFICATIONS 27

5.3 DESIGN CALCULATION 27

5.3.1 Power Calculation 27

5.3.2 Diameter of Shaft 27

5.3.3 Design for Column 28

5.3.4 Design for Clamping Plate 30

5.3.5 Design for Rotating Disk 31

5.3.6 Design for Journal Bearing 32

5.3.7 Design for Shaft 34

5.3.8 Design for Gear box 35

5.3.9 Motor Specification 35

5.3.10 Speed Reduction 35

5.4 CASE STUDY 37

6. DRAWINGS AND IMAGES 39

6.1 AUTO-CAD DIAGRAM 39

6.2 PRO-E DIAGRAM 40

6.3 PHOTOGRAPHIC IMAGE 43

7. CONCLUSIONS 47

8. REFERENCES 48

ABSTRACT

The Passenger coaches of Indian railways are uniquely designed for

comfort as well as safety of the train journey. Considering the speed , safe and jerk

free operation, the coach wheels are not directly mounted on the frame of the

coach. The wheels are assembled in pairs and fixed to a sub assembly called Bogie.

Each coach is provided with two numbers of such bogies in the bottom

which are joined by welding. The vertical load of the coach is directly transmitted

to these bogies equally . As such ,the bogies are of vital in nature which also take

care of the suspension system . These bogies are manufactured in loco works to

meet their own requirements as well as for the replacements of the old damaged

ones in other railway zones.

During the fabrication of these bogies, loco works does not have a

suitable fixture for carrying out the welding operation . As such, we decided to

design and fabricate one such welding fixture for the use of loco works which will

improve the accuracy of welding and also reduces the operation time.

I

LIST OF FIGURES

FIGURE NUMBER DESCRIPTION PAGE NO.2.1 Flux Cored Arc Welding 6

2.2 Overhead Crane setup of

Existing Method

11

6.1 Welding Fixture set up in

Auto-CAD

39

6.2 Bogie Frame in Pro-E 40

6.3 Welding Fixture set up1in

Pro-E

41

6.4 Welding Fixture set up2in

Pro-E

42

6.5 Photographic Image of

Bogie Frame

43

6.6 Photographic Image 1 of

the Welding Fixture

44

6.7 Photographic Image of

Gear Setup

45

6.8 Photographic Image 2 of

the Welding Fixture

46

II

LIST OF SYMBOLS

SYMBOL EXPLANATION UNIT

T Torque N-mm

P Power KW

Fs Shear Stress N/mm2

Wcr Crippling Load KN

Wc Crushing Load KN

I Moment of Inertia mm4

M Bending Moment N-mm

Fcr Crippling Stress N/mm2

Fb Bending Stress N/mm2

β Angle of Contact Degree

K Degrees of Freedom No unit

μ Co-Efficient of Friction No unit

m Module mm

a Center Distance mm

III

LIST OF TABLES

S.No. DESCRIPTION PAGE NO.1 Parts Description 22

2 Bill of Materials 26

IV

CHAPTER - 1

1. INTRODUCTION

The theoretical aspects of practical oriented industrial training in

loco works Indian railway , Chennai helped me to acquire the additional skill

irrespective of the proceeses involved in manufacturing techniques , not

forgetting the quality to be achieved and economy of the manufacturing cost.

This expense to the shop floor gave me practical approach to the day to day

problems very much similar to a normal shop floor production .

The need for increasing productivity by reducing the unnecessary

and difficult work to weld on the side frame in coach bogie in the prescribed

position with the help of unskilled labour . It leads to motivates us to design

such that to avoid monotony to the worker by emphasizing quick method of

rotating and guiding method for welding a side frames in coach bogie.

This project work of manufacturing a “Welding Fixture ” for side

frame in coach bogie been selected with a view to provide immense

opportunity and expose to the solution of the day to day shop floor

problems.

1

CHAPTER - 2

2.LITERATURE REVIEW

2.1 THE BOGIE

2.1.1 DETAILS ABOUT BOGIE

Railway coaches and wagon are designed to carry passengers and

cargo respectively . The upper portion of coach wagon is mounted on a fabricated

structure is called bogies. The bogie consists of

1. Bogie frame

2. Bogie bolster

3. Brake

4. Brake frame wheel suspension coils

IRS BG BOGIE

In BG bogie the weight is taken at the center pivot, which is one of

the bolster through coil bolster coil springs. From here the weight is passed over to

the bogie frame by means of rocker bar and plate assembly . From bogie frame the

weight is transmitted to the auxillary spring through bogie brackets . From here the

bearing springs the weight goes to the axle box , brass , journals and wheel.

IRS MG BOGIE

In MG bogie weight is taken at the pivot top of the bolster . This

weight is transmitted to the bottom springs planks through elliptical bolster spring.

2

The swing link bolt assembly takes up this weight from the bottom springs plank

and transmits to the bogie frame .

From the frame the weight is passed over to the equalizing beam

through the coil springs kept on this beam . since the ends of the equalizing beams

are resting at the crown of the axle boxes , the box , the brass, the journal and the

wheel take up the weight .

2.1.2 BRIEF DESCRIPTION OF BOGIES

The bogies being manufactured by ICF and RCF which have been

accepted as standards on the Indian railways all welded light weight construction .

the axle in these bogies with their self aligning spherical roller bearing mounted

inside the cast steel axle box are rigidly guided by telescopis dashpots and axle

guide assembly. Helical springs working in parallel with dashpots/hydraulic shock

absorber are used for both primary and secondary suspension . The coach body is

supported on two pairs of helical springs supported on a two side bearer located

1600mm apart on a floating bolster which in turn , rests on two pairs of helical

springs supported on asprings plank swung from the bogies frame. The side bearer

consists metal slides (wearing piece & bronze piece) Immersed in oil bath , well

protected from oil dust ingression . no weight is transferred through the bogie pivot

which is located in the center of the bolster . The pivot acts merely as a center of

rotation and serves to transmit acceleration and retardation forces and incorporates

a resilient silent bloc bush , which isolates noise from the track and offers a certain

amount of constraint for noising of the bogies. To floating bolster is secured in the

longitudinal direction to the bogies frame by means of two anchor links with silent

3

block bushing located diagonally opposite to each other and transmit draw and

breaking forces between the bogie and body.

Rigid wheel base – 2896 mm

Wheel diameter(New ) - 915mm

Wheel diameter(Old ) - 813mm

2.1.3 ATTENTION OF BOGIE COMPONENETS

The following attention should be paid to bogie components during POH before

reassembling them.

1. The bogie frame should be checked thoroughly after cleaning for any

possible cracks particularly at places where the bolster suspension brackets

are welded and at the welding joints of top and the bottom flanges of side

frame . Normally squareness and alignment of dashpots does not require

checking .

2. Dismantle the bogie frame from bogie assembly and place it upside down

with the guides up on a suitable stand . In the modified axle box

arrangement, a guide closing plate to be welded.

3. The misalignment of the axle box guides should be measured with reference

to the bolster spring suspension(BSS) bracket.

4. Center punch marks should be made at the center of each BSS brackets and

the measurements taken.

5. The wear on the bush bolster suspension brackets should also be limited to

0.5mm and changed when worn beyond this limit.

4

2.2 WELDING DETAILS

2.2.1 FLUX CORED ARC WELDING

Flux-cored arc welding (FCAW or FCA) is a semi-automatic or

automatic arc welding process. FCAW requires a continuously-fed consumable

tubular electrode containing a flux and a constant-voltage or, less commonly, a

constant-current welding power supply. An externally supplied shielding gas is

sometimes used, but often the flux itself is relied upon to generate the necessary

protection from the atmosphere. The process is widely used in construction

because of its high welding speed and portability. FCAW was first developed in

the early 1950s as an alternative to shielded metal arc welding (SMAW). The

advantage of FCAW over SMAW is that the use of the stick electrodes used in

SMAW is unnecessary. This helped FCAW to overcome many of the restrictions

associated with SMAW.

TYPES OF FCAW

One type of FCAW requires no shielding gas. This is made possible by

the flux core in the tubular consumable electrode. However, this core contains

more than just flux, it also contains various ingredients that when exposed to the

high temperatures of welding generate a shielding gas for protecting the arc. This

type of FCAW is attractive because it is portable and generally has good

penetration into the base metal. Also, windy conditions need not be considered.

Some disadvantages are that this process can produce excessive, noxious smoke

(making it difficult to see the weld pool); under some conditions it can produce

5

welds with inferior mechanical properties; the slag is often difficult and time-

consuming to remove; and operator skill can be a major factor.

Fig.2.1 Flux Cored Arc Welding

Another type of FCAW uses a shielding gas that must be supplied by an

external supply. This is known informally as "dual shield" welding. This type of

FCAW was developed primarily for welding structural steels. In fact, since it uses

both a flux-cored electrode and an external shielding gas, one might say that it is a

combination of gas metal (GMAW) and flux-cored arc welding (FCAW). This

particular style of FCAW is preferable for welding thicker and out-of-position

6

metals. The slag created by the flux is also easy to remove. The main advantages of

this process is that in a closed shop environment, it generally produces welds of

better and more consistent mechanical properties, with fewer weld defects than

either the SMAW or GMAW processes. In practice it also allows a higher

production rate, since the operator does not need to stop periodically to fetch a new

electrode, as is the case in SMAW. However, like GMAW, it cannot be used in a

windy environment as the loss of the shielding gas from air flow will produce

visible porosity (small craters) on the surface of the weld.

2.2.2 PROCESS VARIABLES

Wire feed speed (and current)

Arc voltage

Electrode extension

Travel speed and angle

Electrode angles

Electrode wire type

Shielding gas composition (if required) Note: FCAW wires that don't

require a shielding gas commonly emit fumes that are extremely toxic;

these require adequate ventilation or the use of a sealed mask that will

provide the welder with fresh air.

2.2.3 ADVANTAGE

FCAW may be an "all-position" process with the right filler metals (the

consumable electrode).

7

No shielding gas needed making it suitable for outdoor welding and/or

windy conditions.

A high-deposition rate process (speed at which the filler metal is applied) in

the 1G/1F/2F.

Some "high-speed" (e.g., automotive applications)

Less precleaning of metal required.

Metallurgical benefits from the flux such as the weld metal being protected

initially from external factors until the flux is chipped away.

2.2.4 DISADVANTAGES

Melted Contact Tip – happens when the electrode actually contacts the base

metal, thereby fusing the two.

Irregular wire feed – typically a mechanical problem.

Porosity – the gases (specifically those from the flux-core) don’t escape the

welded area before the metal hardens, leaving holes in the welded metal.

More costly filler material/wire as compared to GMAW.

Less suitable for applications that require painting, such as automotive body

works.

2.3. BOGIE FRAME

Bogie frame sustain the whole coach body weight and rest on axle box coil

springs. In each coach two bogie frame is placed, one in front and other in rear. It

8

acts as a housing for wheels, brakes, batteries, brake frame, bolster, brake cylinder

and various auxiliaries.

The bogie bolster weight and auxiliaries weight are transmitted over to the

bogie frame by corresponding links. By which bogie frame is a very important in

coach.

2.3.1 PARTS OF BOGIE FRAME

Side frame

Transom

Head stock

Longitudinal

Web

Channel

Rib

2.3.2 PARTS TO BE WELDED

Wire rope brackets

Transom brackets

B.S.B(Bolster Suspension Brackets)

Anchor link bracket

Brake cylinder fixing brackets

9

2.3.3 WELDING BY EXISTING METHOD

At present the bogie frame is being rotated with the help of six men and a

bridge crane nearly eight times to carry out continuous run weld.The various steps

which are involved in the rotation of bogie frame are given below :

After the tag welding of top and bottom piece along with ribs and webs, the

bogie frame is carried to fixture, which is stationary.

The bogie frame welding is carried through continuous run weld at one side.

Then the bogie frame is taken out with the help of bridge crane and placed

down.The bogie frame is rotated with the help of bridge crane and placed in

the fixture.

After fixing continuous run welding is carried out.

The bogie frame is then moved in vertical position by using bridge crane.

The welding is carried out in the channels, outer webs and ribs.

10

Fig 2.2 Overhead Crane setup of Existing Method

11

2.3.4 DISADVANTAGES OF EXISTING METHOD :

Inventory cost is more.

Machining cost is more.

Idle time of worker is increased.

Accident prone.

Decreased productivity.

Fatigue to labour.

Labour cost is more.

Fixing cost is more.

Waiting for crane, so time is lost.

Welding accuracy is lost.

Need of skilled labours.

12

CHAPTER - 3

3. NEED OF PROJECT WORK

There is a new innovation made if there is a need. The need is due to

disadvantages of the existing method. The disadvantages in the manufacture of

bogies made us to undertake brainstorming analyses and find an optimal design

and fabrication for rotation of bogie frame.

Bogie frame is one of the main parts in the coach, there must not be any kind

of problems incurred in its manufacturing and functioning during welding and

smaller process also.

The ultimate aim of our project is to provide Loco Works with a rotary

fixture which cannot be seen in either ICF or Carriage Works.

3.1.ULTIMATE ADVANTAGE

Production rate is increased.

Time taken for production is reduced.

Cost of manufacturing is reduced.

Worker idle time is reduced.

Worker motivation is increased.

13

3.2 SCOPE OF THE PROJECT WORK

Present and future scenarios are dealing with reduced time, reduced cost, reduced

in number of labour and complexity. As our project has taken into account the

present scenarios and it has risen up with a best solution to overcome the problems

faced by existing method. The project has got a wider scope, as it is user friendly

and and doesnot involve much cost.

This project deals with the design and fabrication of welding fixture of

bogie frame using worm wheel mechanism. The fixture is used in all types of

industries wherever there is need for increase in production when the heavy object

is to be tilted and welded.

The project will enumerate various problems and various parameters

identification and analysis using problem solving technique. Brainstorming and

arriving at a comprehensive design of the fixture. The calculation and cost analysis

of the fixture is done.

This fixture considerably decreases the inaccuracy in welding and increases

the production rate which in return will reduce the fatigue.

3.2.1 PROBLEM ANALYSIS

In this existing method, no fixture is used for welding of side frame in coach

bogie. Every time a crane is used to turn it. Since side frame is in ‘I’ in cross

section if it has to be run welded 4times and the best position for welding is down

hand welding and the workpiece mount be at 60* so it has to be in turned on swing

by 60* on turn it upside down. In the current method the work piece is placed on a

14

V-block like stand and no fixture is used in holding it to a position and frame is

fixed to position by its own weight.

3.2.2 LIMITATIONS

To turn the work piece, crane is involved which may be in need to other

parts of the shop.

It takes more time for turning the side frame each time using crane.

More risk is involved when overhead cranes are used to rise and turn the

workpiece.

Once the welding is started on the side frame, handling it using crane is

difficult.

Hence to overcome the above limitations we have suggested, designed,

manufactured and implemented a “ WELDING FIXTURE” which helps coach in

coach bogie side frame welding.

3.3 THE FIXTURE

A fixture may be defined as a device which holds and locate a workpiece

during an inspection or for a manufacturing operation. The fixture does not guide

the tool. In construction the fixture comprises different standards or specially

designed work holding devices which are clamped on the machine table to haold

the work in position . The tools set at the required position on the work by using

gauges or by manual adjustment.

15

3.3.1 DIFFERENCE BETWEEN THE FIXTURE AND A JIG

Fixture holds and positions the work but does not guide the tool, whereas a

jig holds, locates and guides the tool

Fixture are generally heavier in construction and are bolted rigidly on the

machine table, whereas the jigs are made lighter for quicker handling and

clamping with the table is often unnecessary.

The fixture are employed for holding work in milling, grinding, planning or

turning operation whereas the jigs are used for holding the tool and guiding

the tool particularly in drilling, reaming or tapping operations.

3.3.2 ADVANTAGES OF FIXTURE

Increases productivity.

Enable production of identical work.

Reduce operator fatigue.

Enable semi skilled labour to perform task.

Increases machining accuracy.

Cost reduction

3.3.3 DESIGN PRINCIPLES OF FIXTURES:

Before planning of the toll, compare the cost of production of the work with

the present tools with the expected cost of production using the tool to be

made and see that the cost of building is not excess of expected gain.

Before laying out the fixture decide the outline points and outline a clamping

arrangement.

16

Make all clamping and binding devices as quick acting as possible.

In selecting locating points, see that these component part of the machine

can be located from the corresponding points and surfaces.

Make the fixture “tool proof” so that no work in other hand the required job

cannot be inserted.

Locate the clamps so that they will be in the best position to resist the

presence of the cutting tool when at work.

Make if possible, all clamps integrated part of fixture.

Avoid complicated clamping which are fixable to weak or get out of order.

Place all clamps as nearly as possible opposite to some bearing parts of work

to avoid impinging.

Carry out all unnecessary metal, making the tools as lighter as possible ,

consistent with rigidity and stiffness.

Rounded all corners.

Provide handle whenever these will make the handling of the fixture more

convenient.

Make if possible all the locating points visible to the operator when placing

the work in position.

LOCATING ELEMENT

These Position the workpiece accurately with respect to tool setting or tool

guiding elements in fixture.

17

CLAMPING ELEMENTS

These hold the work piece securely in located position during operation.

TOOL SETTING ELEMENT

This aid in setting the tool in correct position with respect to workpiece.

PROPERTIES

Fool proofing

Clearance

Rigidity

Safety

Economical

FOOL PROOFING

It is defined as the incorporation of design in the fixture , which prevents

wrong loading of workpiece in fixture. This is provided by a fool proofing pin.

CLEARANCE

It is provided for two reason to allow any variation in component sizes. To

allow any hard movements so that the workpiece can easily be placed in the

fixture.

RIGIDITY

Fixture must be rigid enough to withstand all vibration while machining.

18

SAFETY

Sharp corner must be avoided.

Slight surfaces must be cleared.

Bolts and nuts should not protrude on the outside.

ECONOMICAL

The fixture should be rigid and light in weight. It should also be very economical

in cost.

3.4 MATERIALS USED IN FIXTURE

This is mainly used for cutting tools. These can hold be oiled as air

hardened to 64-66 R.C.18% tungsten and also contains 4.3% chromium , 1.7%

vanadium and smaller quantities of carbon,molybdenum etc.

CARBON STEELS

This can be used for standard cutting tools .They contain 0.85% carbon

0.5% to 0.8% manganese and a small quantity of silicon. These can be water

hardened to 62.63 hardness . These can be used for drill bushes, locators and other

parts , which are subjected top wear and need to be hardened.

MILD STEEL

It is used for most of the parts in the jigs and fixture . Mild steel

contains less than 0.3% of carbon and 0.1% to 0.8% of manganese steel En 32 falls

in this category . This can be case hardened to 56RC free cutting steels caontains

less than 0.15% carbon and cannot be hardened . Generally all parts, which require

19

no hardening , are made of mild steel because it is cheapest material available

among the steels.

NYLON AND FIBRE

These are used as soft lining for clamps top denting of damage to

workpiece due to clamping pressure . Nylon or fibre pads are screwed or struck to

mild steel clamps.

CAST IRON

Used for odd shapes to save machining and laborious fabrication, cast

iron usage requires a pattern for casting . Pattern cost should be compared with

cost of machining and fabrication . Cast iron contains 2 to 2.5% carbons . It can

withstand vibrations well and it is suitable for bases and bodies if milling fixtures .

Self lubricating properties of cast iron make are suitable for machine slides and

guide ways.

PHOSPHER BRONZE

When screw operated clamps is worn out the screw as well as the nuts

needs to be replaced . Generally screw are longer and costlier than nuts . So nuts

are made or phosphor which has tensile strength . As phosphor bronze is softer

than mild steel it wear out before the mating screw without causing much wear of

the steel screw .

Phosphor bronze nut bushes can be replaced periodically and thus , the

life of the steel screw can be prolonged . Nuts for lead screws of most of the

machine tools are made of phosphor bronze.

20

HIGH TENSILE STEELS

Used mainly for fasteners such as high tensile screw these contain 0.4

to 0.6 to 1% Manganese . These can be oil hardened to 45 to 50 RC.

21

CHAPTER – 4

4. FABRICATION OF ROTARY FIXTURE

4.1 PROPOSED ROTARY FIXTURE

In order to avoid the disadvantages of existing method we have designed a

fixture which has greater advantage when compared to the existing method.

The proposed method consists of well suited rotary fixture that is capable of

rotating the bogie frame and guides the same for operation to be performed.

During this all the necessary design calculation is taken care. Even though we

have got various method of operation, fixture is capable of rotating the bogie

frame comfortably. The main advantage of selected fixture is that it is workers

friendly and at the same time it saves the money and increase the productivity.

4.2 PARTS DESCRIPTION

The various assembly components in the rotating fixture are

SNo Parts Description

1 Base plate This is the lower most part, which form the base and the

entire components rest on it.

2 Pillar This is column pair which rest on the base plate. A standard

ISM”I” channel is used of length 1135mm.

22

3 Supporting

plate

This is a additional plate, which is generally provided

inorder to place housing arrangement about it.

4 Bearing

housing

It is just like a stand for placement on it.

5 Shaft It is just like a roller or rod in bearing which rotate the

rotating disc through the motor drive.

6 Rotating disc This is one rotating part which rotates the rotating disc

through motor drive.

7 Clamping

plate

This is a U type channel to clamp the bogie frame according

to the position.

8 Bolt(HL) HL bolts, which are used in worm wheel are used to sustain

the partial.

9 Worm wheel This has a diameter of 800 mm and number of teeth is 46.

10 Gear box It is used to reduce the speed according to the requirements.

It transmits the power to the worm wheel through worm.

11 Motor This is a 7.5 hp motor with a rated speed of 1445 rpm.

23

4.3 FABRICATION PROCEDURE

The various steps involved in fabrication are

Initially the entire sub components are made during assembly.

All the components are first applied with chalk powder and the centre point

is marked using scriber,measuring tape,divider,try square etc.,

Place the two pillar on the top of the base plate at the centre position

between according to the distance by using welding.

Take the supporting plate amd tag weld it over the pillar.

The whole assembly 0f housing and journal bearing is placed at the centre

of supporting plate through tag weld.

Now take a rotating disc and tag weld to the shaftin either one supporting

place on either disc through tag weld.

Apply grease in the bearing and then insert the shaft with the disc.

Place the work wheel at the right end of other side of the shaft through tag

weld.

To provide the table arrangement according to the position for sustaining

the worm wheel and gear box and to the motor arrangement.

Worm is fixed to the worm wheel.

Worm is mounted on the shaft through key and keyway arrangement

tightly.

24

Gear box connects to the sprocket wheel through the small shaft.

Sprocket wheel connects the pinion through standard drive.

Pinion attach to the motor shaft through the key and keyway arrangement.

Paint the fixture and this completes our fabrication procedures successfully.

4.4 ADVANTAGES OF PROPOSED METHOD

Semi skilled labour can do the work.

Idle time of the worker is reduced.

Reduced fatigue.

Increased productivity.

Once after fixing there is no use of bridge crane.

Setting and fixing time is reduced.

Welding accuracy is obtained.

Maintenance cost is low.

Less labour cost as less labour is involved.

25

CHAPTER – 5

5. DESIGN CALCULATION

5.1 BILL OF MATERIALS

S.No Parts Nos Volume (cm3)

Weight (kgs)

Cost(Rs)

1 Base plate 2 65550 514.57 16466.24

2 Pillar 2 19058 149.68 4789.76

3 Supporting plate 2 9000 70.65 226.8

4 Bearing housing 2 869.227 6.82 226.08

5 Journal bearing 4 9047.78 71.02 6000

6 Shaft 2 7539.82 59.19 2130.4

7 Rotating disc 2 11128.78 87.36 3144.96

8 Bolt (HL) 7 400

9 Clamping plate 2 1200 94.2 3014.4

10 Worm and worm wheel arrangement

1 250 4500

11 Gear box 1 7500

12 Shaft 1 861.123 8.759 121.67

13 Chain drive 1 1000

14 Motor 1 14000

15 Bolt small 10 250

16 TOTAL 62771.03

265.2SPECIFICATIONS

Material : Mild steel

Density : 7.85 g/cc

Total mass of the bogie frame = 800 Kg

5.3DESIGN CALCULATION

5.3.1 POWER CALCULATION

Torque(T) = W*R

Where ,W = weight of the bogie frame in N.

R = centre distance in mm.

T = 7848*1182

= 9.276×106 N-mm = = 9.276 N-m

Power = (2*π*N*T)/60

= (2*π*3*9.276)/60

= 2.9 KW

5.3.2 DIAMETER OF THE SHAFT

Torque(T) = (π*p*Fs*d3)/16

Fs = shear stress

= 40N/mm2 (from PSG data book page no. 7.7)

27

T = (π*Fs*d3) /16

D = 105.7mm

From PSG data book page no. 7.20

According to R20 series standard diameter is 100 mm

Therefore diameter of shaft = 100 mm

5.3.3 DESIGN FOR COLUMN

Rankines formula for column.

Rankines formula for short column that fails by crushing the failure of the

component is due to both direct and bending(Buckling stress).

{1/{Wc}} = { 1/Wc}+{1/We}

Wcr = crippling load by rankine formula.

Wc = ultimate crushing load for the column.

= Fc x A

We = crippling load obtained by Euler’s formula

= {(Π²xexI)/L²}

L = 2xI (one end fixed and other end free)

L = 2x1135

= 2270mm.

28

I = {(BH³)-(bh³)}/12

= {(150x200³)}-{(150-10)x(200-20³)}/12

I = 31.96X106 mmˆ4

Youngs modulus(E ) = 2.1x105 N/mm².

A = (150x200)-(140x180)

= 4800 N/mm²

K = √I/A

= √31.96X104/4800.

= 81.597mm.

ULTIMATE CRUSHING LOAD

Wc = Fc xA

Fc = crushing stress

Fs = 3200kgf/cm²

Fs = 320 N/mm²

Wc = 320x4800

= 1536000N

= 1536KN

We = {P²xExI}x{L²}

29

= {P²x2x2.1x10ˆ5x31.96x10ˆ6}/2270²}

We = 12855059.66N

Wc = {1/Wc}+{1/We}

= {1/5360000}+{1/12855059.66}

Wcr = 1372058.21N

= 1372.058 KN

Crippling stress = 1372058.216/4800.

= 285N/mm².

Therefore design for column is safe.

5.3.4 DESIGN FOR CLAMPING PLATE

As we are using two clamping plate and load acting on them is 7848 N.

Distribution of load on each clamping plate will be each 3942 N.

Bending moment (M) = {WL}/8

= {3924*0.8}/8

= 392.4 N-m

= 392400 N-mm

30

MOMENT OF INERTIA

I = {bd3}/12

= {800*1503}/12

= 225×106 N-mm

Cripping stress = 1372058.216/4800

= 285 N/mm2

Cripping stress>crippling stress

5.3.5 DESIGN OF ROTATING DISC

Bending moment M = 3924*340 = 1334160 N-mm

Bending stress Fb = {M*Y}/I

Moment of inertia I = {π×(D4-d4)}/64

= {π×(6804)}/64

I = 1.0476×1010

Fb = {M*Y}/I

= {1334160×340}/{1.0476×1010}

= 0.04N/mm2

Safe bending stress Fb = 60 N-mm2

So design is safe.

31

5.3.6 DESIGN OF JOURNAL BEARING

FULL JOURNAL BEARING:

When angle of contact β= 360 known as full journal bearing

Materials = cast iron (from R.S.Khurmi and Ghupta)

Determine bearing length by choosing a ratio i/d from psg data book pg.

no. 7.31

L/D = 1.97 for railway car

L = 1.97x180

= 354.6

But length taken = 225mm

Check bearing pressure

p = W/(LxD)

p = 7848/(225x180)

= 0.1937 N/mm²

Allowable bearing pressure is 3.5 N/mm² from data book.

Therefore the value of p is safe, so the dimension of LxD is safe and

standard.

Assuming a lubricant from table 25.2 from R.S.Khurmi and Guptha

operating temperature is

32

SAE 60 to = 50c absolute viscosity z

= 0.17 Kg/ms

(1kg/ms = 1000 centipoises)

Determine the operating value (ZN/P) for assumed bearing

temperature corresponding value is table 25.3 from R.S.Khurmi and Gupta to

determine the possibility of determining fluid operation.

= (ZN/P) N

= (0.17x3)/0.1937

= 2.6319

= 3

The minimum value for bearing module at which the oil film will break is

given

3K = (ZN/P)

Bearing modules at the point of friction:

K = 7/3

= 2.3

Since calculated value for bearing characteristic no is 3 or more than 2.3,

it will operate in hydrodynamic condition

From table 25.3 clearance C/D = 0.001

33

Determine the coefficient of friction:

µ = {33/108}X{ZN/P}X{D/C}+K

From data book page no. 7.34

K = 0.002

µ = {33/10ˆ8}x3x1000+0.002

µ = 0.0029

so µ<1 the design is safe

5.3.7 DESIGN OF SHAFT

Bending moment M = W*L

M = 3924*400

=156900 Nmm

Moment of inertia I ={π*d4}/64

=4908738.521 mm^4

b =(32*Mb)/(π*100^3)

for solid shaft b = (32*1569600)/(π*1003)

B = 15.98781432 N

Safe bending stress is 60 N

So design is safe.

34

5.3.8 DESIGN OF GEAR BOX

Speed I = 20

No. of starts z = 3

Speed ratio I = z/Z

= 3*20

= 60 mm

Module m = 5 mm

Centre distance a = 180mm

5.3.9 MOTOR SPECIFICATION

Rated speed of the motor = 1440 rpm

Rated current = 11 amps

Rated voltage = 415 volts

Power = 5.5 kw or 7.5 hp

5.3.10 Speed Reduction

Step 1

Speed of Motor = 1440 rpm

Reduction of Speed From motor shaft to sprocket wheel = ½

Speed Of Sprocket Wheel = 1440/2

35

= 720 rpm

Input = 1440 rpm

Output = 720 rpm

Step 2

Speed of Sprocket wheel = 720 rpm

Reduction of Speed From sprocket wheel to worm & worm wheel = 1/20

Speed Of Worm Wheel 1 = 720/20

= 36 rpm

Input = 720 rpm

Output = 36 rpm

Step 3

Speed of Worm Wheel = 36 rpm

Reduction of Speed From worm&worm wheel 1 to worm&worm wheel 2= 1/15

Speed Of Worm Wheel 2 = 36/15

= 2.4 rpm

Input = 36 rpm

Output = 3 rpm

Thus in 3 Stages the speed is reduced from 1440 rpm to 3 rpm.

36

5.4 CASE STUDY

Labour cost per hour = Rs.50

Bogie frame per month = 60

EXISTING METHOD

1.Required man power per bogie frame is = 12 mens

2.Total man hour per month = 60*12

3.Number of man deployed = 4 to 5

4.Labour cost per month = 60*12*50*3

5.Labour cost per year = 60*12*50*3*12

TOTAL = Rs.12,96,000

PROPOSED METHOD

1.Required man hour hour per bogie frame = 7

2.Total man hour per month = 60*7

3. Number of man deployed = 1 to 2

4.Labour cost per month = 60*7*5*1*12

TOTAL = Rs.2,52,000

37

COST SAVED CALCULATION

Total cost saved = [cost of existing method]-[cost of proposed method]

=Rs.12,96,000-Rs.2,52,000

=Rs.10,44,000

TIME SAVED CALCULATION

Time saved per bogie frame = 5 hours

Time saved per month = 5*30

Time saved per year = 5*30*12

=1800 hours

38

CHAPTER – 6

6 DRAWINGS AND IMAGES

6.1 AUTO-CAD DRAWING

Fig 6.1Welding Fixture set up in Auto-CAD

39

6.2PRO-E DRAWING

Fig 6.2 Bogie Frame

40

Fig 6.3Welding Fixture Set up 1 in Pro-E

41

Fig 6.4 Welding Fixture Set up 2 in Pro-E

42

6.3PHOTOGRAPHIC IMAGE

Fig 6.5 Photgraphic Image of Bogie Frame

43

Fig 6.6 PhotoGraphic Image 1 of Welding Fixture

44

Fig 6.7 Photographic image of Gear setup

45

Fig 6.8 PhotoGraphic Image 2 of Welding Fixture

46

CHAPTER – 7

7 . CONCLUSIONS

JUSTIFICATION AND CONCLUSION :

Our designed and fabricated fixture consists of simple assembled parts

which is quite simple in design and fabricated. It has the reduced number of worker

in existing method from four to two for the proposed method.

The features of proposed method are as follows,

The total time saved is nearly three thousand six hundred hours per year.

The overall cost saved is ten lakhs ninety six thousand per year.

Productivity rate is increased.

Reduce the labour cost.

The Future Scope of this project lies in replacing the induction motor to a stepper

motor , in which the rotations would be in steps so that we could get the desired

position of welding accurately than this set up.

CONCLUSION :

The workers use this fixture very easily and effortless and all the

necessary steps are taken into consideration to ensure longer life with higher

accuracy.

47

CHAPTER – 8

8. REFERENCES

1. PSG Design Data book

2. A TextBook of Machine design by R.S.Khurmi & J.K.Gupta

3. Theory of Machines by R.S.Khurmi & J.K.Gupta

4. Strength of Materials by R.K.Bansal

5. http://en.wikipedia.org/wiki/Bogie

6. http://en.wikipedia.org/wiki/Flux_cored_arc_welding

48