This document provides a summary of the author's summer training project at Hindustan Aeronautics Limited (HAL) Korwa. It discusses HAL and HAL Korwa, the facilities at HAL Korwa including manufacturing equipment, products manufactured including avionics systems for aircraft, and services provided like repairs and spare parts supply. It then describes in detail the jig boring machine and electric discharge machining (EDM) processes used at HAL Korwa for precision manufacturing of components.

1. A REPORT ON INDUSTRIAL TRAINING
IN
MANUFAUCTURING SHOP
AT
HINDUSTAN AERONAUTICS LIMITED
KORWA
SUBMITTED TO SUBMITTED BY
Er. AWADHESH KUMAR PRASHUN JAISWAL
MECHANICAL ENGINEERING Roll No:213449
DEPARTMENT B.Tech 4th year (ME)

2. 1
ACKNOWLEDGEMENT
It gives us an immense pleasure to present the report of the Project undertaken by me during summer
training. We owe special debt of gratitude to N. K. NISHAD Manager (Training) at Hindustan
Aeronautics Limited, KORWA for his constant support and guidance throughout the course of my
work. His sincerity, thoroughness and perseverance have been a constant source of inspiration for us.
It is only his cognizant efforts that our endeavours have seen light of the day.
We also take the opportunity to acknowledge the contribution of all the staff members at HAL
KORWA for their full support and assistance during the development of the project.

3. 2
CONTENTS
1. INTRODUCTION TO HAL
2. ABOUT HAL KORWA
3. FACILITY
4. PRODUCTS BY HAL
5. PRODUCTS BY HAL KORWA
6. REPAIR ,MAJOR SERVICING, SUPPLY OF SPARES
7. MANUFACTURING SHOP
 Jig Boring
 Electric Discharge Machine
 Wire Cut EDM Machine

4. 3
INTRODUCTION TO HAL
HAL was established as Hindustan Aircraft in Bangalore in 1940 by Seth Walchand Hirachand to
produce military aircraft for the Royal Indian Air Force. The initiative was actively encouraged by
the Kingdom of Mysore, especially by the Diwan, Sir Mirza Ismail and it also had financial help
from the Indian Government. Mysore was favoured because of the availability of cheap electricity.
The organisation and equipment for the factory at Bangalore was set up by William D. Pawley of the
Intercontinental Aircraft Corporation of New York, an exporter of American aircraft to the region.
Pawley managed to obtain a large number of machine-tools and equipment from the United States.
The Indian Government bought a one-third stake in the company and by April 1941 as it believed
this to be a strategic imperative. The decision by the government was primarily motivated to boost
British military hardware supplies in Asia to counter the increasing threat posed by Imperial Japan
during Second World War. The Kingdom of Mysore supplied two directors, Air Marshal John
Higgins was resident director. The first aircraft built was a Harlow PC-5[3] On 2 April 1942, the
government announced that the company had been nationalised when it had bought out the stakes of
Seth Walchand Hirachand and other promoters so that it could act freely. The Mysore Kingdom
refused to sell its stake in the company but yielded the management control over to the Indian
Government.
In 1943 the Bangalore factory was handed over to the United States Army Air Forces but still using
Hindustan Aircraft management. The factory expanded rapidly and became the centre for major
overhaul and repairs of American aircraft and was known as the 84th Air Depot. The first aircraft to
be overhauled was a Consolidated PBY Catalina followed by every type of aircraft operated in India
and Burma. When returned to Indian control two-years later the factory had become one of the
largest overhaul and repair organisations in the East. In the post war reorganization the company
built railway carriages as an interim activity.

5. 4
After India gained independence in 1947, the management of the company was passed over to the
Government of India.Hindustan Aeronautics Limited (HAL) was formed on 1 October 1964 when
Hindustan Aircraft Limited joined the consortium formed in June by the IAF Aircraft Manufacturing
Depot, Kanpur (at the time manufacturing HS.748 under license) and the group recently set up to
manufacture Mig-21 under license (with its new factories planned in Koraput, Nasik and
Hyderabad). Though HAL was not used actively for developing newer models of fighter jets, the
company has played a crucial role in modernization of the Indian Air Force. In 1957 company
started manufacturing Bristol Siddeley Orpheusjet engines under license at new factory located in
Bangalore.
ABOUT HAL KORWA
Welcome to the Avionics Division, Korwa of Hindustan Aeronautics Limited. Avionics Division
Korwa was established in the year 1982, to take up the production of Display Attack Ranging and
Inertial Navigation (DARIN) system for Jaguar International aircraft for Indian Air Force. Since,
1987 Korwa Division has also been manufacturing and supplying similar avionic systems for MiG-
27 aircraft to IAF. All the facilities required for manufacture of such advanced airborne avionic
systems are available under one roof. The Division of HAL, has been built in a pollution free
environment sprawling over approximately 1 million sq.mts. of lush green area including complete
amenities for a residential complex. The total covered area for manufacturing is around 38000 sq.
mts. The Division has got a highly skilled work force of approximately 1100 including 200 highly
qualified engineers.

6. 5
FACILITY
For the manufacture of advanced avionic systems, Korwa Division has well equipped laboratories,
modern test facilities and advanced high accuracy automatic production equipment and machines as
mentioned
High precision of CNC Machining Centres, Lathes, Milling machines
High precision Jig Borers & Jig Grinders
CNC Tool & Cutter Grinder, EDM, Electron Beam Welding machines
Precision Tool Room/Process Shop with Heat Treatment and Plating facilities.
Optical Component fabrication facilities
Automatic Test Equipment for testing of Electronic modules
Laser Trimming & Dynamic Balancing of Gyroscopes
General Purpose ATE for Repair & Testing of Multilayer PCBs having VLSI/Hybrid components
Super Clean and Controlled environment rooms (upto Class 100)

7. 6
PRODUCTS BY HAL
 Su 30 MKI - Twin-seater, Multi-role, Long range Fighter / Bomber / Air Superiority Aircraft
 MiG-27 M - Single-seater Tactical Fighter / Bomber with variable sweep wings
 MiG-21 VARIANTS - Single-seater Front line Tactical Interceptor / Fighter Aircraft
 METALLIC DROP TANKS - The Division manufactures different types of metallic drop
(Jettisonable) tanks with capacity of 490 and 800 litres
 UNDERCARRIAGE - The Division has facilities and expertise in the manufacture and
overhaul of Undercarriages of both MiG-27M and MiG-21 variants. The landing gears are of
a conventional tricycle type and consist of one steerable Nose wheel leg and two Main wheel
legs to roll the aircraft in motion, on the ground, during take-off run and landing run. The
Landing Gear legs have Pneumatic shock absorbers.
 EJECTION SEAT - The Ejection Seat is installed to provide safe escape to the Pilot from
the Aircraft while catapuling is effected with the help of a combined Ejection Gun. The
Division has the facilities and expertise in the manufacture and overhaul of ejection seats for
both MiG-27M and MiG-21 variants.

8. 7
 CANOPY -The Division manufactures and overhauls canopies of MiG-21 variants and MiG-
27M Aircraft.
 FLEXIBLE RUBBER FUEL TANKS - The Division manufactures and supplies all types of
Rubber Fuel Tanks required for MiG-21 Variants. The Rubber Fuel Tanks are provided with
special protection coating against Ozone/heat and adverse climatic conditions.
 PRECISION COMPONENTS- The Division also produces precision components like: total
gamut of Blades ranging from Compressor Rotors and Stators to Turbine Blades and Nozzle
Guide Vanes, intricate Cored Magnesium Alloy Gear Casings, Compressor and Turbine Discs
and Shafts, JIS class-l/DlN 5 Spur, Helical Gears and DIN 6 straight and Hypoid / Spiral
Bevel Gears ranging from module 1 to 6.
 HYDRAULIC SYSTEM AND POWER CONTROL- Hydraulic Pumps, Accumulators,
Actuators, Electro-selectors, Bootstrap Reservoirs and various types of valves
 ENVIRONMENTAL CONTROL SYSTEM- Cold Air Unit, Water Extractors, Non
Return Valves and Venturies
 ENGINE FUEL CONTROL SYSTEM- Fuel after Burner regulator and distributor, Main
Fuel Distributor, Regulator and After Burner Pump, Plunger Pumps, Fuel Metering Device
 INSTRUMENTS- Electrical Indicators, Fuel quantity and flow metering instruments, Flight
instruments, Sensors and Switches
 ELECTRICAL POWER GENERATION AND CONTROL SYSTEM-AC/DC
Generator, Control and Protection Units, AC and DC Master Box, Inverters, Transformer
Rectifier Unit, Actuators
 UNDERCARRIAGE, WHEELS AND BRAKES -Main and Nose Undercarriage, Main
and Nose Wheel, Brake System LRUs
 TEST RIGS -Dedicated Test Rigs, custom-built Fuel/Hydraulic Test Rigs and Electrical
Test Rigs

9. 8
PRODUCTS BY HAL KORWA
Currently korwa Division is manufacturing the Navigation, Ranging, Display and Attack Systems for
both jaguar and MiG-27 aircraft.
Brief details of the avionic system are as under:
Jaguar avionics
Jaguar avionicsInternational Navigation System
Stabilized Inertial Platform with Dry-tuned Gyroscopes and Accelerometers
Digital Nav-Attack Computer
Interface Unit and Cockpit Control Panels
Head-Up Display & Weapon Aiming Computer (HUDWAC)
Microprocessor based head-up Display & Sighting System
Scan and Cursive modes of display
Weapon Aiming Computations in Reversionary modes in the event of failure of INS Computer
Combined Map and Electronic Display (COMED)
Head Down Navigation & Map Display
Soft key Selectable Display Modes
Integrated with INS and HUDWAC on MIL-STD 1553B Digital Data bus
Flight Data Recorder (FDR)
Crash protected Flight Data Recording System with Data Acquisition unit
Simultaneous recording of Data and Audio tracks
Recording Duration of 90 minutes in endless loop
Laser Ranger and Marked Target Seeker (LRMTS)
Operates both in Ranging and Target Seeking modes
Target Range Computation
Neodymium Doped YAG Laser
Autostabliser System (AUTOSTAB)
Computer Based System for Control of Tailplane, Rudder and Spoiler Movements
Incorporate BITE Facility

10. 9
MiG-27M Avionics
MiG-27M AvionicsIntegrated Navigation And sighting Complex (44 LK System)
Inertial Navigation System
Centralized Digital Computer
Radio and Doppler Navigation
Stabilised Sight
Air Data Computer
Laser Ranging System
Flight Data Recorder (UZL TESTER)
Recording Duration of 3 Hours
Crash Protected Recording System
Records 38 Analogue and 32 Discrete Parameters

11. 10
REPAIRS, MAJOR SERVICING, SUPPLY OF SPARES
This Division undertakes the repair and overhaul of the airborne avionic systems of Jaguar, MiG-27
and Mirage-2000 aircraft throughout the lifecycle of the product.
The Division also provides the comprehensive customer services and support to Indian Air Force
(IAF). The broad spectrum of customer services provided by the division comprises of the following.
Supply of spares to Indian Air Force
Quick response and fast turnaround servicing of avionic systems and LRUs
Regular workshops both at in-house training school and at Air Force bases to the IAF personnel
Updation of the avionic systems to cater to the needs of the customers for the induction of new
armaments and weapon systems.
Design, manufacture and supply of the computer based dedicated, special to Type test Equipment to
IAF.
Apart from the above, Korwa division provides similar services to other customers e.g. indian Navy,
Army and other defence organisations for the products akin to our production range.

12. 11
MANUFACTURING SHOP
JIG BORING MACHINE
• Jig borers are vertical boring machines with high precision bearings.
• It was developed primarily for accurately locating and producing holes in precise locations.
They are also called precision co-ordinate measuring machines. It’s used for making
numerous holes necessary for jigs, fixtures, gauges and other precision parts.
• The most important tool used in jig borers is: single- point boring bar. Other tools like drills,
reamers, and counter borers are also used.
• Very important tool before age of computer-controlled machining centers.
• Jig boring is used to accurately enlarge existing holes and make their diameters highly
accurate. Jig boring is used for holes that need to have diameter and total runout controlled to
a high degree. Typically, a part has holes machined on regular equipment and then the part is
transferred to a dedicated jig boring machine for final operations on the especially accurate
holes.
• Jig boring can also maintain high accuracy between multiple holes or holes and surfaces.
Tolerances can be held readily within ±.005 mm (±0.0002 inches). Dedicated jig boring
machines are designed to machine holes with the tightest tolerances possible with a machine
tool.
• When designing a part with holes, it is important to determine what holes must be jig bored.
The reason for this is that jig boring requires extra time and attention. Jig boring can therefore
have a big impact on the lead time of a part. A cross section of a hole being jig bored is
shown below.

13. 12
• Standard boring can be carried out on a mill fitted with a boring head or on a lathe. Boring is
accurate on a lathe since a lathe is dedicated to solids of revolution (axially symmetric parts).

14. 13
DESCRIPTION:
 A jig borer is built lower to the floor & is much more rigid and of highly accurate
construction.
 On the base of it a saddle is supported which move in and out from the operator to the
column. A table is provided to supplement the saddle movement which can move to right or
left.
 Third position adjustment is achieved by the movement of a massive column which support
the spindle housing which is capable of moving up and down the column ways.
 The spindle moves inside the quill, and the quill moves up-down inside housing, thus giving
Telescopic mechanism.
 For purpose of high accuracy & precision, the spindle, quill and housing are manufactured
under careful conditions. The spindle and spindle bearing are constructed with very high
accuracy.
 To minimise the errors due to thermal expansion, the housing is made of Invar Cast Iron.
 Driving mechanism provides speeds ranging from 30 to 1500 r.p.m. so that best cutting speed
is there for each size holes.
 It is very important for the proper use of jig borer that it is kept in a temperature controlled
room.
 In jig boring only soft material up to a certain hardness can be machined like aluminium,
brass and steel.
Single point boring tool consist of a round shaft with one insert pocket designed to reach into a part hole
or cavity to remove internal stock in one or several machine passes.

15. 14
Advantages of boring over reaming: Better finish is obtained. Boring can be done for all sizes while
in reamers only standard sizes available. Reamer have a tendency to run away from central axis
hence reamers do not give excellent surface finish.
COMPARISON OF BORING ON A BORING MACHINE AND LATHE
LATHE JIG BORER
For a normal boring operation on a
lathe, the work revolves mounted in the
chuck or on the faceplate, and the
single-point boring tool is set to cut and
feed.
For the corresponding operation on a jig-borer, the work
is stationary on the machine table, while the single-point
boring tool revolves and is fed.

16. 15
On a lathe, however, it would mean
loosening and resetting the work, a
longer and more difficult job.
The table of the jig-borer can be moved by accurate feed
screws in two directions at right angles, the position of a
hole can be located on the feed screw micro meter
collars. The positions of other holes can be obtained by
using end gauges against stops.
ELECTRIC DISCHARGE MACHINE (EDM)
 EDM is a thermo electrical material removal process, in which the tool electrode shape is
formed as mirror image on work piece surface.
 The machine tool holds an electrode, which advances into the work material and produces a
high frequency series of electrical spark discharges.
 The EDM phenomenon can be divided into three stages namely application of adequate
electrical energy, dielectric breakdown, sparking and expulsions (erosion) of work material.
 The control of erosion of the material is achieved by rapidly recurring spark discharges
produced between the electrode and work piece.
 Localised extreme rise in temperature of 10,000
o
C leads to material removal due to instant
vaporization of the material as well as due to melting. However, the heat affected zone is
limited to only 2 – 4 μm of the spark crater as there is not enough time for the heat to diffuse
towards work piece.
 The metal removal rates and surface finish are controlled by the frequency and intensity of
the spark. With high sparking frequencies the spark erosion gives substantial metal removal
rates. It has been found that high frequency and low amperage settings give the best surface
finish.
 The higher amount of erosion occurs at the positive electrode, therefore, to have maximum
material removal from work piece and have minimum wear on tool, the tool is made cathode
and work piece as anode.
 Material removal depends on mainly thermal properties of the work material rather than its
strength, hardness etc.

17. 16
Functions of the Dielectric are as follows:
 Insulation: One important function of the dielectric is to insulate the work piece from the
electrode. The disruptive discharge (a sudden large increase in current through an insulating
medium resulting from failure of the medium to withstand an applied electric field) must take
place across a spark gap which is as narrow as possible. In this way efficiency and accuracy
are improved.
 Ionization: After the impulse the spark path must be de-ionized quickly so that the next
discharge can be made. The dielectric ought to constrict the spark path as much as possible,
so that high energy density is achieved, which increases discharge efficiency at the same
time.
 Cooling: The spark has a temperature of 8,000-12,000° C when it punctures the work piece
and so the dielectric must cool both the electrode and the work piece. Overheating of the
electrode must be avoided, so that excessively high electrode wear cannot occur. It must be
possible for the metal gases which develop during spark erosion to condense in the liquid.
ADVANTAGES
1. EDM has no contact and no cutting force process, and therefore does not makes direct contact
between tool electrode and the work material. This eliminates the chances of mechanical
stress, chatter and vibration problems, as is prominent in traditional machining.
2. No complicated fixtures are needed for holding the job.
3. Material of any hardness can be cut.
4. High accuracy and good surface finish are possible.
5. Intricate-shaped cavities can be cut with modest tooling costs.
6. Holes completed in one “pass”
7. The EDM process is burr-free.
8. Thin fragile sections such as webs or fins can be easily machined without deforming the part.
DISADVANTAGES

18. 17
1. Electrode wear takes place during the EDM operation when the electrode (i.e. the tool) gets
eroded due to the sparking action.
2. Limited to electrically conductive materials.
3. Slow process, particularly if good surface finish and high accuracy are required
4. Dielectric vapour can be dangerous.
5. Tool life is limited.
6. There is a possibility of taper and overcut in EDM.
CHARACTERISTICS OF EDM:
PARAMETERS VALUES
Spark gap 0.005 mm - .125 mm
Spark frequency 100-500 KHz
Peak voltage
across gap
30-250 V
MRR 5000 mm3/min.
Dielectric fluid EDM synthetic hydrocarbon
Tool material Do not know ( maybe copper )
Wire Cut Electric Discharge Machining
The Wire Electric Discharge Machining (WEDM) is a variation of EDM and is commonly known as
wire-cut EDM or wire cutting. In this process, a thin metallic wire is fed on-to the work piece, which
is submerged in a tank of dielectric fluid such as de-ionized water. This process can also cut plates as
thick as 300mm and is used for making punches, tools and dies from hard metals that are difficult to
machine with other methods. The wire, which is constantly fed from a spool, is held between upper
and lower diamond guides. The guides are usually CNC-controlled and move in the x–y plane. The
wire-cut EDM is every useful used for cutting very intricate and delicate shapes.
 In the wire-cut EDM process, deionized water is commonly used as the dielectric fluid.
 Wires made of brass are generally preferred with diameter between 0.02 and 0.30 mm.
 The deionized water helps in flushing away the debris from the cutting zone. The flushing
also helps to determine the feed rates to be given for different thickness of the materials. The
schematic of wire cut EDM is shown in Figure.

19. 18
The WEDM process requires lower cutting forces in material removal. Hence it is generally used
when lower residual stresses in work piece are desired (as in case of aircraft parts).
If the energy/power per pulse is relatively low (as in finishing operations), little changes in the
mechanical properties of the material are expected due to the low residual stresses. The materials
which are not stress-relieved earlier can get distorted in the machining process.
PROCESS OF MATERIAL REMOVAL IN WEDM
In the WEDM process, the motion of wire is slow. It is fed in the programmed path and material is
cut/ removed from the work piece accordingly. Electrically conductive materials are cut by the
WEDM process by the electro-thermal mechanisms. Material removal takes place by a series of
discrete discharges between the wire electrode and work piece in the presence of a dielectric fluid.
The dielectric fluid gets ionized in between the tool-electrode gap thereby creating a path for each
discharge. The area wherein discharge takes place gets heated to very high temperatures such that the
surface gets melted and removed. The cut particles (debris) get flushed away by the continuously
flowing dielectric fluid.
WEDM is a non-conventional process and is very widely used in tool steels for pattern and die
making industries. The process is also used for cutting intricate shapes in components used for the
electric and aerospace industries.
Applications of Wire-Cut EDM
 Wire EDM is used for cutting aluminium, brass, copper, carbides, graphite, steels and
titanium. The wire material varies with the application requirements. Example: for quicker
cutting action, zinc-coated brass wires are used while for more accurate applications,
molybdenum wires are used.

20. 19
 In aerospace industry, WEDM is used to manufacture parts including engine, fuel system,
and landing- gear components, as well as other high-stress, high-temperature parts.
 Virtually all commercial, scientific, and military aeronautical and aerospace hardware has
used parts manufactured partially or in whole by WEDM.
 The aerospace industry needs the WEDM process to make many of the components used in
aircraft because of the intricate shapes, tough alloys, and very tight tolerances involved.
Subsystems of wire EDM
 Power supply.
 Dielectric system.
 Wire feeding system.
 Positioning system.
The power supply and di-electric system used in WEDM is very similar to that of the
conventional EDM. The main difference lies only in the type of dielectric used. In wire cut EDM, a
moving wire electrode is used to cut complex outlines and fine details in the required work piece.
The wire is wound on a spool and is kept in constant tension. The drive system continuously delivers
the fresh wire on-to the work area. New wire is continuously exposed to the work piece hence the
wear of the wire (tool) is not the major issue in WEDM process. The wire feeding system consists of
a large spool of wire and rollers which direct the wire through the machine. The presence of metal
contact provides power to the wire and guides it further in-order to keep it straight throughout the
cutting process. The other parts are the pinch rollers which provide drive and wire tension.
Process Parameters in WEDM
The process parameters that can affect the quality of machining or cutting or drilling in WEDM
process are as follows:
 Electrical parameters: Peak current, pulse on time, pulse off time and supply voltage and
polarity.
 Non-electrical parameters: Wire speed; work feed rate, machining time, gain and rate of
flushing.
 Electrode based parameters: Material and size of the wire.
 Dielectric System: Type, viscosity, and other flow characteristics.

21. 20
CONCLUSION
The joy of flying has fascinated the human race for centuries. Defense avionics major & Navratana
PSU Hindustan Aeronautics Limited ( H A L) is in the business of building a w hole range of
aircraft , helicopters and jet trainers .Besides , the company manufactures aircraft components,
overhauls fighter planes and trains future pilot’s . its success in the design and development of light
combat aircraft Tejas and advanced light helicopter Dhruv has won admiration. HAL is the backbone
of India’s air defense and continues to occupy the strategic importance reflecting a new pace of
growth.Today the faster growing sector is the aviation sector & is likely to be a boon for the entire
job market . It deals with the manufacture, design & development of aircrafts.The project is based on
the instruments that are used in the manufacture of the various aircrafts. A deep knowledge of these
instruments is crucial in the perfect design & manufacture of the air crafts. The project will benefit
those who have interest in the instrument & will provide the reader with the deeper knowledge of the
topic.