Sri Lanka Air Force Base- Katunayaka

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  • ACKNOWLEDGEMENTS

    It was a great opportunity to me for completing my industrial training in one of Sri Lankas

    most important establishments such as Sri Lanka Air Force which is South Asias one and only

    establishment overhauling helicopters. It was even more enthusiastic to work with a group of very

    highly skilled professionals, who were very friendly from the commencement of my training session.

    First of all I must thank Industrial Training and Career Guidance Unit (ITCGU) of faculty of

    Engineering, University of Peradeniya and National Apprentice and Industrial Training Authority

    (NAITA) for conducting the training program and allowing us to get the required industrial exposure

    for achieving challenges which should overcome by engineers in the industrial environment.

    Then I offer my sincere thanks to the Commanding Officer of Mechanical Transport Repair and

    Overhaul Wing (MTR&OW) Group Captain Eng. Senarathna who was in-charge of us during the

    training session and to Squadron Leader Eng N.S. Dikkumburage, Flight Lieutenant Eng. Chamila

    Mallawarachchi, Squadran Leader Eng. Chamila Kahadakoralage who were in-charge of the training

    session and also to Squadron Leader Eng. G.G.I.D. Viraj who was in-charge of workshop Engineer.

    I must further thank, all workers who were at Air Craft Engineering wing, General Engineering

    Wing, Mechanical Transport Repair & Overhaul Wing for helping me without any hostility to improve

    my knowledge. Actually it was a strange experience for me at the beginning of the training period and

    I could spend valuable and pleasurably 11 weeks with aid of all the personnel who has given the

    support and the assistance in completing my industrial training session.

    E.M.K.S. Edirisooriya

    Faculty of Engineering

    University of Peradeniya

  • iii

    CONTENTS

    Acknowledgements i

    Contents iii

    List of Figures v

    List of Abbreviations vi

    Chapter 1 INTRODUCTION

    1.1 Introduction to Sri Lanka Air Force 1

    1.2 SLAFs vision & mission 1

    1.3 Rank Structure 3

    1.4 Decorations & medals 3

    1.5 Sri Lanka Air force base, Katunayaka 4

    Chapter 2 DISASSEMBLY OF A DEFFENDER TDI ENGINE

    2.1 Disassembling process 8

    2.2 Important points to be considered 8

    Chapter 3 ASSEMBLY OF DEFENDER TDI ENGINE

    3.1 Assembling process 10

    3.2 Settling tappet clearance 11

    3.3 Important points to be considered 12

    Chapter 4 DISASSEMBLY OF DEFENDER TDI GEAR BOX

    4.1 Disassembling process 14

    4.2 Important points to be considered 15

    Chapter 5 ASSEMBLY OF DEFENDER TDI GEAR BOX

    5.1 Assembling process 16

    5.2 Important points to be considered 17

    Chapter 6 THE TRANSFER BOX

    6.1 Function of a transfer box 18

  • iv

    Chapter 7 LATHE MACHINES

    7.1 Main parts of lathe machine 19

    7.2 General operation of lathe machine 20

    7.3 External Threads cutting operation 21

    7.4 Important points to be consider 21

    Chapter 8 WELDING

    8.1 Metal inert gas welding (MIG) 23

    8.2 Gas welding 23

    8.3 Tungsten Inert gas welding (TIG) 24

    Chapter 9 NON DESTRUCTIVE TESTING

    9.1 Radiographic testing 26

    9.2 Magnetic particle testing 26

    9.3 Ultrasonic testing 26

    9.4 Eddy current testing 27

    9.5 Penetrate testing 27

    Chapter 10 CONCLUSIONS 28

  • v

    LIST OF FIGURES

    Figure 2.1 Cross section of a diesel V engine 8

    Figure 2.2 Cross section of a Pushrod and overhead cam engine 9

    Figure 3.1 Measuring by using a dial gauge 10

    Figure 3.2 Measuring gap of a piston ring 10

    Figure 3.3 A piston ring compressor(Ring Clamp) 11

    Figure 3.4 Adjusting tappet clearance 11

    Figure 3.5 Setting tappet clearance 12

    Figure 3.6 The Engine head 13

    Figure 4.1 The components of a gearbox 13

    Figure 4.2 Separation of the gearbox 14

    Figure 4.3 Dog teeth in a gearbox 14

    Figure 5.1 Components of the Gearbox 15

    Figure 5.2 Components of the hub 15

    Figure 6.1 Components of a transfer box 16

    Figure 6.2 Components of a transfer box 17

    Figure 7.1 Main Components of a Lathe Machine 17

    Figure 7.2 A Lathe Machine 19

    Figure 8.1 The welding process 20

    Figure 8.2 Welding process 21

    Figure 8.3 The diagram of the MIG welding 21

    Figure 8.4 The diagram of the Gas welding 22

    Figure 8.5 The diagram of the TIG welding 22

    Figure 9.1 NDT testing 23

    Figure 9.2 Ultrasonic testing 24

    Figure 9.3 Eddy current testing 25

  • vi

    LIST OF ABBREVIATIONS

    AEW AIRCRAFT ENGINEERING WING

    GEW GENERAL ENGINEERING WING

    LROW LAND ROVER OVERHAUL WING

    MTR&OW MECHANICAL TRANSPORT REPAIR & OVERHAUL WING

    SLAF SRI LANKA AIR FORCE

    TDI TURBOCHAEGED DIRECT INJECTION

  • 1

    Chapter 1 INTRODUCTION

    1.1 INTRODUCTION TO SRI LANKA AIR FORCE

    Sri Lanka Air Force has been reputed to occupy the most advanced technology and machinery

    in the country out of the three military forces operating in Sri Lanka at present. It has 16 base stations

    covering the entire island, and 3 training bases. There are 5 stations which carry out Flying Formation

    - Katunayake, Rathmalana, Higuraggoda, Anuradhapura and Vauniya. The 12 squadrons are situated at

    these 5 bases. Housing flying formations are where they carry out day to day flying activities.

    SLAF is a child of Royal Air Force in United Kingdom. Before the independence Royal Air

    Force was carrying operation in Sri Lanka. SLAF was established by an act of parliament in 1949, act

    number 41 of 1949. The exact date of the formation of the Air Force is however, taken as 3rd

    March

    1951. The first commander of the Air Force, Air Commodore G. C. Blaydon and Royal Air Force was

    appointed to command the Royal Ceylon Air Force. On 22nd

    may 1972, when Sri Lanka was declared

    a republic, the name of the Royal Ceylon Air Force was changed to the Sri Lanka Air Force.

    In our training period, the commander of the Sri Lanka Air Force is Air Chief Marshal Roshan

    Gunathilake who is a son of the former Air Commander Air Vice Marshal W.D.H.S.W Gunathilake.

    As well as Sri Lanka Air Force is dedicating for welfare activities. The objectives of those

    activities are offering support to service personnel and their families to improve their living conditions

    and morale.

    1.2 SLAFS VISION & MISSION

    1.2.1 Vision

    TO ESTABLISH AN AIR FORCE OF HIGH OPERATIONAL EFFICIENCY

    TO PRESERVE THE SOVEREIGNTY

    OF SRI LANKA

  • 2

    1.2.2 Mission

    TO PROVIDE HEAVY MAINTENANCE FACILITIES FOR

    THE AIRCRAFT OPERATIONAL FORMATIONS. FURTHER, THE RESOURCES

    AVAILABLE MAY ALSO BE USED TO UNDERTAKE COMMERCIAL PROJECTS WITH

    PRIOR

    1.2.3 Vision of DAE

    To achieve flight safety and aircraft serviceability to its

    highest standard, through improved competency and

    work perfection.

  • 3

    1.3 RANK STRUCTURE

    1.3.1 Commissioned Officers

    Air Chief

    Marshal Air

    Marshal Air Vice

    Marshal Air

    Commodore Group

    Captain Wing

    Commander Squadron

    Leader Flight

    Lieutenant Flying

    Officer Pilot

    Officer

    1.3.2 Other Ranks

    Warrant Officer Flight Sergeant Sergeant Corporal Leading Aircraftman

    1.4 DECORATIONS & MEDALS

    Parama Weera

    Vibushanaya

    Weerodhara Vibhushanaya

    Weera Wickrama

    Vibhushanaya

    Rana Wickrama Padakkama

    Rana Sura

    Padakkama

    Vishishta Seva Vibhushanaya

    Utthama Seva

    Padakkama

    Videsha Seva Padakkama

    Republic Of Sri

    Lanka Armed

    Services Medal -

    1972

    Sri Lanka Air Force 25th

    Anniversary medal - 1976

    Queen Elizabeth II

    Coronation

    Medal - 1953

    Ceylon Armed Services Long

    Service Medal - 1968

    Sri Lanka Armed

    Services

    Long Service

    Medal-1979

    President's Inauguration

    Medal - 1978

    50th Independence

    Anniversary

    Commemoration

    Desha Putra Sammanaya

    North & East

    Operations Medal

    Purna Bhumi Padakkama

    Vadamarachchi

    Operation Medal

    Sri Lanka Air Force 50th

    Anniversay Medal

    Riviresa Campaign

    Service Medal

    Ceylon Armed Services

    Inauduration Medal -1956

    United Nations' Service

    Medal (CONGO)

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  • 4

    1.5 SRI LANKA AIR FORCE BASE, KATUNAYAKE

    The Sri Lanka Air Force Base Katunayake,

    the largest Air Force Base in Sri Lanka , is situated in

    close proximity to the Bandaranayke International

    Airport. The Base provides administrative, logistical,

    general and civil engineering services to all lodger

    formations located within the Base. The following

    flying Squadrons are among the major lodger

    formations in the base

    No. 04 Helicopter Squadron

    No. 05 Jet Squadron

    No. 10 Fighter Ground Attack Squadron

    No. 14 Squadron

    In addition to the above flying formations the following formations are also located within the Base.

    Supply & Maintenance Depot

    Electronic & Communication

    Command Argo Unit

    Runway Maintenance Wing

    Aeronautical Engineering Wing

    General Engineering Wing

    Aircraft Spares Depot

    Air Defence Cmd & Control Center

    Hospital

    Radar Maintenance Wing

    Motor Transport Repair Operating Wing

    No 26 Regiment Wing

    Air Field Construction Wing

    No 43 Color Wing

    No 62 Intelligence Wing

    Parachute Training School

    Mechanical & Electrical Wing

    Dental Unit

    SLAF Band

    No 01 Air Defence Radar Squadron

    Special Project Unit

    Equipment Provisioning and Accounting Unit

  • 5

    A fully equipped gymnasium, a swimming pool and a cinema are among the many recreational and

    sports facilities offered by the Base for its personnel. The housing complex located within the Base

    provides accommodation to several hundred families of the AF personnel serving at the SLAF Base

    Katunayake.

  • 6

    ORGANIZATION OF SLAF

    3 O

    F 7

    CO AP &

    SU

    BASE

    COMMANDERS

    COS OF

    SQUADRONS

    CO

    AEW

    OCM

    NO 2 (HTS)

    SQUADRON

    OCM

    NO 1 (FTW)

    SQUADRON

    OCM

    NO 3 (MARI)

    SQUADRON

    OCM

    NO 14 (JET)

    SQUADRON

    OCM

    NO 11

    (UAV)

    SQUADRON

    OCM

    NO 7 (HELI)

    SQUADRON

    OCM

    NO 4 (HELI)

    SQUADRON

    OCM

    NO 9 (AHS)

    SQUADRON

    OCM

    NO 10 (KFIR)

    SQUADRON

    OCM

    NO 5 (JET)

    SQUADRON

    OCM

    NO 6 (HELI)

    SQUADRON

    OCM

    NO 8 (LTS)

    SQUADRON PILOTS

    COMMANDER OF SRI LANKA AIR FORCE

    DAE DIRECTOR OF

    AERONAUTICAL

    ENGINEERING

    CHIEF OF STAFF

    DGE DIRECTOR OF

    GENERAL

    ENGINEERING

    DOPPS DIRECTOR OF

    AIRCRAFT

    OPERATIONS

    DHS DIRECTOR

    OF HEALTH

    SERVICES

    DW DIRECTOR

    OF

    WELFARE

    DP

    DIRECTOR OF

    PLANNING

    DETE DIRECTOR OF

    ELECTRICAL &

    TELECOMMUNICATION

    ENGINEERING

    DA DIRECTOR OF

    ADMINISTRATION

    DT DIRECTOR

    OF

    TRAINING

    DCE DIRECTOR OF

    CIVIL

    ENGINEERING

    DL DIRECTOR

    OF

    LOGISTICS

    MINISTER OF DEFENSE

    PRESIDENT OF SRI LANKA

  • 7

    ORGANIZATION OF AEW

    SNCO I/C

    CIVIL

    CONTROL

    SNCO I/C

    DISCIPLIN

    ARY

    SNCO I/C

    ORDERL

    Y ROOM

    OC

    SPECIAL

    PROJECT

    WIN

    G

    WAR

    RAN

    COMMANDING OFFICER

    OC TECH

    PLANNING

    &

    CONTROL

    OC

    ADMINISTRATION

    OC

    AR &

    SS

    OC

    PSES

    OC

    AVIONICS

    OC

    LOGIST

    IC

    WO I/C

    SAFETY BAY

    WO I/C

    COMPO

    NENT

    BAY

    WO I/C

    NDT LAB

    WO I/C

    ROTOR

    BAY

    WO I/C

    AR &

    SS

    WO I/C

    SPECIAL

    PROJECT

    WO I/C

    ENGINE

    BAY

    WO I/C

    ELECTRICAL

    BAY

    WO I/C

    INSTRUMENT

    BAY

    SNCO

    I/C

    FORWA

    RD

    SNCO I/C

    ORDERLY

    ROOM

    WING

    WARRAN

    T

    OFFICER

    WO I/C

    COMPONEN

    T BAY

    WO I/C

    ROTOR

    BAY

    WO I/C

    AR & SS

    WO I/C

    TECH

    PLANNING

    & CONTROL

    WO I/C

    SPECIAL

    PROJECT

    WO I/C

    ENGINE BAY

    SNCO I/C

    FORWAR

    D SUPPLY

    UNIT

  • 8

    Chapter 2 : DISASSEMBLY OF A DEFENDER TDI ENGINE

    Figure 2.1: Cross section of a diesel V engine

    2.1 Disassembling process

    The procedure is initiated by removing the oil sump by removing purge nut sump. Next attempted the

    drain water in the cooling system, but since the drain nut system is corroded cooling becomes difficult

    and there the water in the system that was in the system without removing. Then the injector pump,

    vacuum pump, oil filter and the front cover were removed. After that the pressure plate, clutch plate,

    inlet and exhaust manifolds were removed. Then the flywheel, the tappet cover, rocker shaft, push

    rods, intor nozzles, heater plugs, valve tips, engine head and the cam followers were removed. After

    the motor is turned upside down and the crankcase oil filter end bearings and main bearings were

    removed and the pistons were removed. Next the cam shafts and the oil swans were removed.

    All components except the engine head, injection pump, oil pump, water pump and front cover washed

    using Auta and was cleaned with pressurized water components jet. Finally well dried with

    compressed air and They were oiled to prevent rusting.

    2.2 Important points to be considered

    1. Engine heads are never washed using Auta. If not the gasket will perish and sealing the engine

    head to the engine block want happen properly.

    2. As soon as the components are dried, it should be oiled to prevent the formation of rust. But

    not all need to be oiled. Finally component surfaces and surfaces with fine surface finish.

    Eg: cylinder bores, cam faces, bearing sleeves, cam rollers and crank shafts are the components

    that need to be oiled. After that the engine block was washed using Auta and was cleaned and

    dried. Finally, the cylinder bores were oiled.

  • 9

    3. Banjo bolts should not be tightened using excessive torques. If so they will fail under torsion

    4. Nuts and bolts smaller M10 tight are must always be removed using a hexagon socket.

    (Open end wrenches can be used. But tend to slip damaging the hexagonal nut or bolt. When

    this repetition, gradually impossible to be removed or secured with a key becomes.)

    Figure 2.2: Cross section of a Pushrod and overhead cam engine

  • 10

    Chapter 3: ASSEMBLY OF A DEFENDER TDI ENGINE

    3.1 Assembling process

    The assembly process began by fixing the swans. Next oil hoses main bearings and thrust bearings

    were fitted and were oiled. Then, the crankshaft is placed in place and the remaining halves of bearings

    (bearings main) is attached and bearing caps were fixed. The end-play of the crankshaft was checked

    using a dial gauge.

    Figure 3.1: Measuring by using a dial guage

    The final game is usually set to 7 min. After the gap of piston rings were measured. This as is done by

    inserting a ring into the hole, pushing the piston and then measure the gap using thicknesses gauges.

    The process was repeated three rings. (the gap for the compression ring should be 0.6mm, whereas for

    compression and rings should be 0.4 mm.)

    Figure 3.2: Measuring gap of a piston ring

    Then, the piston rings inserted into the pistons using a circlip plier. Next pistons inserted into the hole

    using a clamp ring and piston were pushed into place using a hammer and a wooden pole. Then

  • 11

    bearings were inserted head and covered it attached. The carrying handle is rotated after setting each

    piston in order to ensure that there are no obstructions and the crank rotates continuously.

    Figure 3.3: A piston ring compressor (Ring Clamp)

    Then the camshaft is mounted and the feed pump and vacuum pumps fixed. Then the bell was

    attached. After that the gears were set and the timing belt was overlooked and so tense using suitable

    matrix tensioner .Then the cover was fixed and the damper pulley, pulley fan, power steering pump

    pulley attached. Then the wheel set and twice crankshaft is rotated to ensure obstructions. After

    absence of ant oil filter and drain cap were fixed. Next the cam followers were fixed. Then the motor

    head and push rods were inserted. After noticed that the rocker was placed correctly and was fixed.

    The game Valves set to 0.2 mm using the 'nine method'. After the cover pusher respite unit, injection

    pump, injectors and glow plugs were fixed. Finally the inlet and exhaust manifolds were fixed.

    Figure 3.4: Adjusting tappet clearance

    3.2 Settling tappet clearance

    First rocker arm adjuster adjuster is loosened completely. Next decreased to almost touch the valve

    end. Then the valve tip and 0.2 mm thickness gauge is placed over the valve was placed to tip. After

    the adjuster is reduced to gauge. Finally touched firmly held probe adjuster closed place by tightening

    the screw.

  • 12

    Figure 3.5: Setting tappet clearance

    The Nine methods

    This method is used only for the defender TDI engine. The process involve four steps.

    1. Turn the crank and observe the valves to see which valve is rising.

    2. Turn the crank continuously until the rising valve stops its motion(At the beginning of the

    Dwell of the valve cam)

    3. If the valve is the nth valve then tappet clearance is set to the (9-n)th valve.

    4. Tappet clearance is set as mentioned above

    3.3 Important points to be considered

    When tightening bolts a torque wrench should be used(Specially in fixing the flywheel,

    connecting rods and the engine head)

    1. A torque of 40 Nm is used for flywheels.

    2. A torque of about 40 Nm is used for the connecting rods.

  • 13

    At the top of the engine; Initially all nuts are tightened with a torque of 40 Nm. Next whole nut is

    rotated by 60 0 .After all nuts are rotated once again by the two central rows 60

    0.Finally nuts is further

    rotated by other 20 0(This is done in order to ensure that the nuts are tightened to the proper torque). If

    not at times due to the presence of rust etc. the actual torque may be less than the value set in the

    torque wrench.

    Figure 3.6: The Engine head

    3. When fastening the nuts of the connecting rods and the engine head a diagonal pattern ( Nuts

    are tightened alternatively, starting at the middle and progressing to the ends.)should be used in

    order to prevent distortion.(The reverse of the pattern must be used in removing the nuts)

  • 14

    Chapter 4 DISASSEMBLY OF DEFENDER TDI GEAR BOX

    4.1 Disassembling process

    Figure 4.1 : The components of a gearbox

    First the transfer case is removed from the gearbox. Then the gear selector switch and four-wheel drive

    was removed. Then the bush in the gearbox is removed by heating using an oxyacetylene cutter and

    lever out of position using two types levers. After that the accommodation and the gear assembly was

    taken retired out. Next shaft top, main shaft, lay shaft and idler wheel removed. Then reverse forks

    hubs. Next withdrew from the security rings, brushes, O-rings, needle bearings and tapered roller

    bearings possible were removed and the main shaft It was taken to the hydraulic pressure. Bearing

    larger tapered roller was not removed and the gears were eliminated one after the other. Next to dogs

    and retaining springs are eliminated.

    Figure 4.2 :Separation of the gearbox

  • 15

    4.2 Important points to be considered

    1. When removing the bush, care should be taken not to damage the edges.(If the edges get

    damaged the oil seals at the ends of the bush will get turn off)

    2. After removal of the components, dog teeth of the hubs and gears should be checked. If that

    have disappeared and have been rounded pointy teeth, the wheel or the axle has to be replaced.

    If not want to participate adequately gears. Also the tip of the gear teeth should be checked for

    cracks or fractures. If a crack or a broken gear wheel is located, should be replaced

    Figure 4.3: Dog teeth in a gearbox

  • 16

    Chapter 5 ASSEMBLY OF A DEFENDER TDI GEARBOX

    Figure 5.1: Components of the Gearbox

    5.1 Assembling process

    First retaining springs are fixed to the hub and the struts (tooth struts / Dogs) held in a person place.

    While all three keys simultaneously pressed into the sleeve is inserted into position by another. Both

    hubs were assembled similarly. Next sprockets cones brass, bronze and slippers cone centers are

    arranged in order in the splined shaft and the components were Locke in place with security rings

    when needed. Then the completed main shaft was placed in the holder and the other hub was inserted

    onto the shaft. Next the forks of that hub was fixed. Then the reverse ideal wheel was mounted on the

    shaft and the link slides in and out of position fixed. After the shaft holding the forks fixed in position

    after placing the upper shaft forks. Next remained place and the lay shaft was fixed. Then the gear

    assembly was inserted into the housing properly and the screws were tightened. After the oil seal,

    guides, and the bell were fixed. Finally the gear selector was fixed and coupling speed checked.

    Figure 5.2: Components of the hub

  • 17

    5.2 Important points to be considered

    1. Care must be taken in setting the tapered roller bearings in the middle, and in the end. They

    never be beaten. Should be placed using a hydraulic press. Even in the process, the force must

    be applied with intense care. (Applying pressure should be stopped if you feel an obstruction

    to waive force. If bearing damage.)

    2. It should be clear that the two fork slots and slot the shifter idle must be aligned before

    inserting the set of gears in the housing. (If not certain gears may not engage)

  • 18

    Chapter 6 THE TRANSFER BOX

    Figure 6.1 : Components of a transfer box

    The transfer case is connected to the transmission and the front and real axles per unit means of shafts.

    This also known as "gearbox transfer", Transfer Case "," Jockey box "or" T-box ")

    6.1 Function of a transfer box

    1. Power transmission is received and sends it to the front and rear axles. This can be done either

    by gears or chain drivers. In some transfer cases operating mode can be switched between "four

    wheels" and "two-wheel drive "through a shifter, while others are operated using switches. The

    guy who left is not selectable transfer boxes (box Defender transfer is selectable transfer box

    with a driven gear shifter,)

    2. In the transfer path boxes synchronize the rotation difference between the front and rear

    wheels. This necessary when front and rear types rotate at different speeds because of the

    difference in tire sizes. (In simple terms transfer boxes act as central differential gear)

    3. In off-road vehicles, transfer boxes acts as differential locks.

    Figure 6.2 : Components of a transfer box

  • 19

    Chapter 7 LATHE MACHINES

    Around a power driven, general purpose machine tool used for production of the cylindrical work

    piece. As the metal piece to be machined is rotated on the lathe, a single tool cutting point is advanced

    radially into the work piece a specified depth and longitudinally moved along the axis of the work

    piece, the removal of metal in the form of chips. Both inside and outside surfaces can be machined on

    a lathe. By using attachments and accessories, other operations such as drilling, boring, and the conical

    shape and angle of rotation, screw thread persecution, knurling, milling, grinding and polishing can be

    done.

    Figure 7.1: Main Components of a Lathe Machine

    7.1 Main parts of lathe machine

    1. Headstock

    The head is attached on the left side of the bed, which is formed by the spindle drive gear and

    shift levers. Three jaw chuck jaws and four plate are most commonly used to hold or clamp the

    work piece to be cut.

    2. Tailstock

    The counterpoint is on the right side of the bed. It can be locked in any position along the bed

    of the lathe tailstock clamp. It can be used to support long work piece during the cutting

    process. Counterpoint spindle is used to receive the deadlock, which provides support for the

    far right of the work.

    3. Bed

    The bed is a heavy, rugged casting made to support the working parts of the lathe. On its top

    section are machined ways that guide and align the major parts of the lathe.

  • 20

    4. Lathe carriage

    Around the truck carrying the cutter (tool post) and precisely controls the movement is parallel

    to the ways called turning straight or right angle to form, called front. The car mount has three

    main parts, the compound rest, and an apron.

    5. Face Plate

    A faceplate is used to drive a lathe dog which in turn is firmly attached to the work piece.

    Contains more open slots or grooves in T so that the bolts or screws T can be used to secure the

    work piece to the face plate. Many types of work that can not be kept in baboons may

    conveniently be machined when mounted on the faceplate.

    6. Three jaw universal Chuck

    A three jaw chuck work holding cylindrical or hexagonal. The three jaws move together to

    bring the work in the center. Two sets of interchangeable jaws are provided. These are called

    inside and outside jaws.

    7. Four Jaw independent Chuck

    The four-jaw independent chuck is used to hold most of the work for which a mandrel is

    required. The jaws of hardened steel are reversible and sustain work of different sizes and

    shapes. Each jaw can be moved independently of the others so that the work pieces can be

    delivered accurately to run. A four-jaw independent chuck has several circular grooves around

    the face of the body. The jaws can be approximately centered by adjusting the jaws to these

    slots. The work piece is then inserted and tightened jaws enough to hold the job instead.

    Reverse the tool, tighten finger tight only, and make it until it touches the work piece. Rotate

    the dish by hand to locate the high or low point of the work piece. Adjust the jaws until the

    work piece runs true. If more precision is required, using a test indicator.

    7.2 General Operation of Lathe Machine

    Turning Operation : Turning operation is used to reduce the diameter of a cylindrical work piece. A

    single cutting tool removes the material from a rotating work piece to generate a

    cylindrical shape.

    Facing operation : Tool is fed radially inward direction and facing the work piece. Normal facing is

    done from outer edge to the center of the work piece.

    Taper Turning : The diameter of a work piece changes uniformly from one end to other.

  • 21

    Chamfering : Cutting edge cuts an angle on the corner of the cylinder forming a chamfer.

    Figure 7.2: A Lathe Machine

    7.3 External Threads cutting operation

    First, the cutting of the thread is mounted on the tool post at right angles to the work that was aligned

    correctly using a screw cut meter. Then a slow turn had to be selected so that the need for sufficient to

    reverse or remove the cross slide and turn off the machine at the end of the thread time. The work

    piece is turned required outer diameter and a beveled edge was machined on the free end of the work

    piece. Each thread was cut in several steps. The depth of cut can not be great if you can not overload

    the motor may fall or tip the tool. Turn back or remove the cross slide at the end of each cut, the motor

    is reversed to bring the tool to the starting position. The tool is adjusted to a new cutting depth by

    using reading hand wheel cross slide. Lastly, cleaning the cut thread profile he was done and cleaned

    up the thread.

    7.4 Important points to be considered

    1. The cutting depth should be adjusted around 1mm per one step

    2. After the cutting outline of the threads, it should be checked whether the cut is on desired pitch

    by using a thread pitch gauge.

    3. When the tool reaches the end of the cut quickly tool is turned to away from the work piece

    using the cross slide crank.

  • 22

    Chapter 8 WELDING

    Figure 8.1 : The welding proces

    Figure 8.2 Welding process

    WELDING

    PROCESS

    Fusion welding

    process

    Gas welding

    Oxy acetylene

    Oxy hydrojen

    Arc welding

    Unshielded arc Inert gas shield

    arc

    MIG welding

    TIG welding

    Atomic hydrogen arc

    Submerged arc

    Other processes

    Pressure welding process

    Black smith's forge welding

    Electric Resistance

    welding

    Spot welding

    Projection welding

    Seam welding

    Butt welding

    Flash Butt welding

    Cold pressure welding

    Friction welding

  • 23

    8.1 Metal Inert Gas Welding (MIG)

    First the machine was turned on and the CO2 cylinder valve was opened. Next metal strips are held in

    place with a little space between them. The ends were then labeled. Finally he completed welding

    accordingly

    Figure 8.3:A diagram of MIG welding

    8.2 Gas welding

    First the oxygen cylinder valve and acetylene cylinders opened and the gas in the cylinders were

    confirmed. Next both pressure adjusting screws (ie, oxygen and acetylene) were completely oxygen

    valves closed. Then and acetylene cylinder valve is opened needle respectively. Next acetylene torch

    was opened. the screw pressure was adjusted to obtain the desired pressure and the needle valve was

    closed. The same was repeated with the needle valve. Then oxygen needle valve acetylene opened a

    swing and ignited using a spark igniter or flame. After the oxygen needle valve was slowly opened

    until the flame oxidant obtained. Finally strips metal were marked at the extreme ends are welded

    accordingly

    Figure 8.4: A diagram of Gas welding

  • 24

    8.3 Tungsten Inert Gas Welding (TIG)

    First the tungsten electrode was checked to confirm that the tip is in good condition, Next machine

    became a cylinder valve argon opened. Then settings were chosen to adapt accordingly the material to

    be welded. Next the metal strips were kept in place with a diameter equal to the gap filler wire. After

    labels are placed on the welding was completed ends.

    Figure 8.5: A diagram of TIG welding

  • 25

    Chapter 9 NON DESTRUCTIVE TESTING

    Non-destructive testing (NDT) is a new synthetic scientific technology that is a powerful tool for

    reducing costs, improving product quality, and maintaining quality levels. It is a test that includes all

    possible methods of detection or measurement of the properties or performance capabilities of

    materials, parts, assemblies or structures, which dont impair their serviceability. There are six

    methods using in NDT lab of AEW.

    Visual testing

    Radiographic testing

    Ultrasonic testing

    Eddy current testing

    Magnetic particle testing

    Liquid penetrant testing

    Procedure of NDT.

    Inspection

    Measurement

    Monitoring

    Figure 9.1: NDT testing

  • 26

    9.1 Radiographic testing (RT)

    When rays pass through the matter, some of these rays are absorbed. The amount of absorption

    depends upon the thickness and density of the matter; therefore, the intensity of the rays emerging

    from the matter varies. The intensity of rays at the point where there is no defect is greater than that

    where defect exists. When this variation is detected, the quality of the matter can be determined.

    9.2 Magnetic particle testing

    When there exists a discontinuity in the material, magnetic force line will make a detour round the

    discontinuity. If the flaw is on or near the surface of material, some magnetic force line will run out of

    the material, and magnetic leakage field is produced. Then when you spray some magnetic particles or

    liquid on surface, the leakage field will adsorb particles and form a flaw indication. From the magnetic

    indication, flaws can be easily determined

    9.3 Ultrasonic testing

    Ultrasonic wave can enter into material, and it will be reflected at the interface between two agents.

    Ultrasonic waves are generated and accepted by probe, which is one part of the ultrasonic detector and

    includes straight probe and slope probe. The piezoelectric crystal of them is the key unit for energy

    transducer, the function of it is generating longitudinal wave and finishing conversion between

    acoustic energy and electric energy.

    Figure 9.2 Ultrasonic testing

  • 27

    9.4 Eddy current testing

    Eddy current is produced in the tested material. And for different material or in different state, the

    eddy current is different. If there lies a flaw, the eddy current field at the flaw will be different from

    that at the other place. So we can determine whether or where the flaw lies.

    Figure 9.3 Eddy current testing

    9.5 Penetrate testing

    Color liquid or fluorescent liquid suck into the out crack in the work piece. Then clear the surface of

    work piece. If you use a sorbent to suck out the liquid, the image of crack will appear

  • 28

    Chapter 10 CONCLUSIONS

    Engineering is not an easy task as a career. It is essential to have good practical knowledge and also

    experience to do the task effectively. As engineers we are responsible to do several occupations. He

    must play various characters once he is an advisor, once he is a manager, once he is a manager

    likewise an engineer should have good personality to handle everything properly. As an engineer he

    should be able to associate with every person in the site as well. He should be able to create good

    communication with each other to enhance the work in the site. And he has the ability of labor

    handling.

    The efficiency of the SLAF was incredibly high and the quality of the outputs were unmatchable any

    other production. But massive scale safety of the workers were questionable. Workers were safety

    shoes and eye protection but hardly wear hearing protection and better masks. In some arrangements

    can do to complete workers to use safety equipment.

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