hindustan aeronautics limited overhual division, bangalore

Project Report

on

“DESIGN OPTIMIZATION OF TOOL REQUIREMENT FOR

FATIGUE STRENGTH IN HAWK-MK132 AIRCRAFT”

Submitted by

J.B RAVI KIRAN 1NH14ME408

MOLAKA KALYAN 1NH14ME412

DINU KRISHNAN 1NH11ME013

In partial fulfillment of

BACHELOR OF ENGINEERING

IN

MECHANICAL ENGINEERING INTERNAL GUIDE: EXTERNAL GUIDE:

Mrs.RESMY.J.DEVAN Mr.RAJA NAIK

Asst. Professor Quality Manager, Department of Mechanical Engineering, Hawk Quality Dept,

N.H.C.E, Bangalore. Overhaul division, H.A.L,

Bangalore.

Project work carried out at

Hindustan Aeronautics Limited Overhual Division, Bangalore-560017

DEPARTMENT OF MECHANICAL ENGINEERING

NEW HORIZON COLLEGE OF ENGINEERING BANGALORE-560 103

2016-17

NEW HORIZON COLLEGE OF ENGINEERING

DEPARTMENT OF MECHANICAL ENGINEERING

CERTIFICATE

It is certified that the project entitled "Design Optimization of Tool

Requirement for Fatigue Strength in Hawk-Mk132 Aircraft” is a

bonafide work carried out by J.B.RAVI KIRAN (1NH14ME408), MOLAKA

KALYAN (1NH14ME412) and DINU KRISHNAN (1NH11ME013) for the partial

fulfillment for award of degree of Bachelor of Engineering in Mechanical

Engineering of New Horizon College of Engineering, Bangalore during the year

2016-2017. It is further certified that all corrections/suggestions indicated for internal

assessment has been incorporated in the report deposited in the department library.

The Project has been approved as it satisfies the academic requirements in respect of

Project Work prescribed for the Bachelor of Engineering degree.

Signature of the guide

Signature of the HOD

Signature of the Principal Mrs RESMY.J.DEVAN Dr. M S GANESHA PRASAD Dr MANJUNATHA

Asst. Professor, Dean-Students Affairs & HOD-ME, Principal,

Dept. of Mechanical Engineering. Dept. of Mechanical Engineering. NHCE.

External Examiner(s) Signature with Date

1.

2.

DECLARATION

I hereby declare that the entire work embodied in this dissertation has been carried

out by our group and no part of it has been submitted for any degree of any institution

previously.

Date: Signature of the student

Place: Bangalore

CERTIFICATE

This is to certify that the above declaration made by the candidate is correct to the

best of my knowledge and belief.

Place: Bangalore RESMY J DEVAN

Date: Asst Professor

Department of Mechanical Engg,

N.H.C.E, Bangalore.

J.B.RAVI KIRAN 1NH14ME408

MOLAKA KALYAN 1NH14ME412

DINU KRISHNAN 1NH11ME013

ACKNOWLEDGEMENTS

I thank the Lord Almighty for showering His blessings on me.

It is indeed a great pleasure to recall the people who have helped me in carrying

out this project. Naming all the people who have helped me in achieving this goal would

be impossible, yet I attempt to thank a selected few who have helped me in diverse ways.

I wish to express my sincere gratitude to Dr. Manjunatha, Principal, NHCE,

Bangalore, for providing me with facilities to carry out this project.

I wish to express my sincere gratitude to Dr. M S Ganesha Prasad, NHCE,

Dean-Students Affairs & Head of Department, Mechanical Engg., for his constant

encouragement and cooperation.

I wish to express my sincere gratitude to my teacher and guide RESMY J

DEVAN, Professor in the Department of Mechanical Engg., NHCE, for his valuable

suggestions, guidance, care & attention shown during the planning, conduction stages of

this project work.

I express my sincere thanks to project coordinators, all the staff members and non-

teaching staff of Department of Mechanical Engg., for the kind cooperation extended by

them.

I thank my parents for their support and encouragement throughout the course of

my studies.

Design Optimization of Tool Requirement of Fatigue Strength in HAWK MK 132 Aircraft

Dept. of Mechanical Engg., NHCE, Bangalore 2016-17

Abstract

In major industrial countries, manufacturing is considered as the most important driving

towards nation’s richness and success. But globalization and consolidation of companies

has resulted in increased competition for manufacturing plants, therefore it is essential for

the claims to their productivity to survive in the competitive market. When it comes to

improving productivity, optimum utilization of machinery and reducing rejections are the

key factors.In Hindustan Aeronautics limited, overhaul division the management

authorities have identified many thrust areas for reducing the lead time of manufacturing

of components. This has resulted in selecting the components. “Alignment pin & landing

gear pintle pin bolts remover” for the project work.Basically, Alignment pins are

manufactured for the standard sizes and the problem facing is unavailability of size

required. Where, the required size of diameter Φ4.67mm. Therefore, we are designing

alignment pin for required dimensions. Landing Gear Pintle Pin Bolts Remover is the

tool, which is designed for easy removal of landing gear & unmounting the pintle pin

located in the wing structure. The main purpose is to reduce manufacturing lead-time and

reduce man-hour rate. It also helps to reduce additional costs due to rework & it is

convenient to use.Analysis based on tools requirement for fatigue modification is carried

out. Therefore, we design & fabricate the suitable tool for respective modification as per

the requirements of the organization where the general tools are not easily accessible.

CONTENTS

CERTIFICATE

ACKNOWLEDGEMENT

DECLARATION

ABSTRACT

CONTENTS

LIST OF FIGURES

LIST OF TABLES

1. INTRODUCTION 1

1.1 HISTORY 2

1.2 FLOW CHART OF ORGANIZATION 3

1.3 BANGALORE COMPLEX 3

1.4 MIG COMPLEX 5

1.5 ACCESSORIES COMPLEX 5

1.6 DESIGN COMPLEX 6

1.7 EVOLUTION AND GROWTH OF COMPANY 7

1.8 ABOUT HAWK AIRCRAFT 8

1.9 SPECIFICATIONS 9

1.9.1 AIRCRAFT FACTS 10

2. MISSION AND VISION 13

2.1 MSSION OF THE ORGANIZATION 13

2.2 VISION 13

2.3 QUALITY POLICY 13

2.4 QUALITY OBJECTIVES 13

2.5 PRINCIPLES AND CONCEPTS OF FIXTURING FOR CNC

CONTROL

14

2.6 DEFINITION OF PROBLEM AND OBJECTIVES 15

2.6.1 DEFINITION OF PROBLEM 15

3. DETAILS OF FIXTURE 17

3.1 ALIGNMENT PIN 17

3.2 LANDING GEAR PINTLE PIN BOLTS REMOVER 18

3.2.1 LIST OF COMPONENTS 18

3.3 ENGINEERING DRAWING 20

3.3.1 ALIGNMENT PIN 20

3.3.2 LANDING GEAR PINTLE PIN BOLTS REMOVER 21

3.4 FINAL ASSEMBLY 23

4. MATERIAL SELECTION 25

4.1 MATERIAL SELECTION 25

4.1.1 ABSTRACT 25

4.1.2 GENERAL PRODUCT INFORMATION 25

4.1.3 SCOPE 25

4.1.4 CLASSIFICATION 26

4.2 REQUIREMENTS 26

4.3 MATERIAL PROPERTIES 27

4.3.1 MECHNAICAL PROPERTIES 27

4.3.2 CHEMICAL PROPERTIES 28

4.3.3 PHYSICAL PROPERTIES 28

5 DESIGN OF FIXTURES 29

5.1.1 CUTTING FORCE CALCULATIONS 29

5.1.2 DESIGN OF EXTERNAL SLEEVE 30

5.1.3 DESIGN OF INTERNAL SLEEVE 31

5.1.4 DESIGN OF SCREW ROD 32

5.2 STRESSES INDUCED IN FINAL ASSEMBLED PART 33

6 JUSTIFICATIONS AND DIMENSIONS 34

6.1.1 JUSTIFICATION OF ALIGNMENT PIN 34

6.1.2 JUSTIFICATION OF BOLTS EXTRACTOR 34

Table

No.

LIST OF TABLES

Particulars

Page

No.

Table1

Material Selection

15

Table2

Mechnaical Properties

18

Table3

Chemical Properties

28

Table4 Dimensions with tolerances 30

DESIGN OPTIMIZATION OF TOOL REQUIREMENT FOR FATIGUE STRENGTH IN HAWK MK 132 AIRCRAFT

Dept. of Mechanical Engg., NHCE, Bangalore 2016-17 Page 1

CHAPTER-1

INTRODUCTION

Hindustan aeronautics limited [HAL] a premier aerospace company in Asia is

engaged in design, development and manufacture of military and civil aircraft for over 5

decades. The product range covers basic piston engine trainer aircraft to helicopters to

sophisticated state of the art deep penetration strike aircraft.

Hindustan aeronautic limited is an organization where integrated air borne

weapons are conceived, developed, manufactured and serviced. It is one of the few

corporate giants in Asia whose capabilities span the entire range of activities from

product conception to after sale support. HAL is also involved in the manufacture and

assembly of structures required for India’s space programs.

In the 6 decades, HAL has spread its wings to cover various activities in the area

of design, development, manufacture and maintenance. Today HAL has 14 productions

division/units, 7 at Bangalore and one each at Nasik, Koraput, Kanpur, Lucknow, Korwa,

Hyderabad and Barrakpore. These centers are engaged in the design and development of

combat aircraft, helicopters, aero engine, engine test beds, Aircraft communication and

navigation systems and accessories of mechanical and fuel systems and instructions.

Aviation is one of the most significant technological influences of our time and

empowers the nation strength. It is the major tool for economic development and has a

significant role in National security and International relations. No other industry is more

international than commercial aerospace. It can be seen that globalization drives in 4

areas. Market, competition, cost and government.

In India the aerospace industry is under control of Government of India under the

remit of Ministry of Civil Aviation (MOCA). The ministry is responsible for formulation

on national policies and programs for development and regulation of Civil Aviation and

for designing and implementation of scheme for orderly growth and expansion of civil air

transport. It also oversees the provision of aircraft facilities, aircraft services and carriage

of passengers and freight.



India has been fortunate to start aeronautics related activities an 1940, with the

establishment of HAL. The largest Indian aircraft manufacture in HAL (PSU) owned

aerospace related companies in South India, centered on the group of companies in

Bangalore. While HAL is mainly defence related, other local companies serve the civil

sector and are involved in the production of light aircraft structure designs, engines,

electronics and other equipment avionics/radar precision parts and materials. Many

companies are collaborating a Joint Ventures or Technology Transfers to manufacture

under license for foreign partners.



CHAPTER-2

HISTORY

Fig2.1 History

Hindustan Aeronautic Limited was founded in Dec 1940 by Shri Seth Walchand

Hirachand as Hindustan Aircraft Ltd. A private limited company and since then the

company has produced over 3300 aircrafts, 3400 aero engines, overhauled over 7700

aircrafts and 26000 engines and produced over 3700 engines.

In 1962, Aeronautic India Ltd was formed to undertake the manufacture MiG-21 aircrafts

as an agreement between Govt of India and Soviet Union (USSR). IN 1964 Hindustan

Aircraft did and Aeronautics India Ltd. After Independence, the company rededicated

itself to the design, development, manufacture and maintenance of aircrafts. During the

50 years of post-independence era, the company has contributed significantly through

vigorous R&D efforts of indigenously designing trainers, fighters, helicopters,

sophisticated airborne and ground equipment, avionics and systems.



HAL has three production complexes (Bangalore, MiG, Accessories) and Design

complex headed by a director/ Managing Director reporting to the chairman. All

complexes are further divided into production divisions and R&D centers.

FLOW CHART OF AN ORGANIZATION

Fig2.2 Organization Chart

BANGALORE COMPLEX

The Bangalore complex of HAL comprises of Aircraft Division, Foundry & Forging

Division, Overhaul Division, Aerospace Division, Industrial & marine gas turbine

Divisions.

1. Aircraft Division

The aircraft division is mainly engaged in manufacture of Jaguar Strike Aircraft,

HAWK, Advanced Jet Trainer, PTA (lakshya)

2. LCA-LSP

A LCA-LSP unit has been set up to handle LCA-Tejas production limited series

production of LCA has started.



3. Aerospace Division

The division manufactures space worthy structures like Satellite Launch Vehicle

(SLV) interstages , propellant tanks and separator mechanism for ASLV, PSLV, GSLV,

IRS and INSAT series of technologies.

4. Aero engine division

The division is involved in state of art manufacture, overhaul and maintenance of Aero

engines for Helicopters and Aircrafts.

5. Industrial Marine and Gas Turbine Division

As a part of diversification plan, industrial and marine gas turbine division has been

formed on 1st April 1998 as a part of Bangalore complex. This division manufactures,

repairs, and overhauls 501K series 3 MW aero derivative gas turbine under license from

M/S, Allison gas turbine, USA, HAL supports over 40 such engines in India used by

GAIL, OGNC and RSEB. In addition, IMGT division carries out onsite maintenance of

RB-211 engines and overhaul of 17MW Industrial Avon Engines of ONGC under

arrangement with M/S, Rolls Royce.

6. Overhaul Division

This division is involved in major servicing and overhaul of associated rotables in respect

of Kiran MK-1/MK-1A/MK-11, Jaguar and Mirage 2000 aircrafts.

7. Foundry and Forge Division

The division capabilities include precision casting, sand casting and ring forgings. The

division is also involved in the development of material and alloys for aerospace and

defense applications.

MIG COMPLEX

Nasik Division

This division was established as a manufacturing base for MiG series of aircrafts.

The division involved in repair and overhaul of Mig 21, MiG21 BIS &MiG 27.



Koraput Division

The division undertakes manufacture and overhaul of R11 and R25 series

engines and R 29B engines. The division also has excellent hot forging and precision die

casting facilities.

ACCESSORIES COMPLEX

Hyderabad Division

These divisions undertake production and servicing of avionics, Air Route Surveillance

Radar (ARSR), Precision Approach Radar (PSR), and assembly of components and sub

systems for IAF/ ARMY/ NAVY/ COAST GUARD/ SPACE and other civil applications.

Transport Aircraft Division-Kanpur

The division manufactures HPT-32 and DORNIER 228 aircrafts. The division is

supported by R&D center.

Luck now Division

The division is involved in manufacturing of mechanical and hydro-mechanical

accessories, fuel system and instrument accessories for the complete range of aircrafts

produced in HAL.

Korwa Division

The capabilities of this division covers the manufacture, repair and maintenance of

Advanced Avionics Systems for military aircraft of Eastern Origin covering inertial

navigational systems, head up displays, weapon aiming computers, combined map

electronic display, laser ranger and marked target seeker, integrated navigation and

sighting complex.

DESIGN COMPLEX

1. Helicopter Division

The division currently undertakes manufacture, repair and maintenance of Chetak

(Aloutte 111) and Cheetah (Lama SA 3158) helicopters. The division is also engaged in



series production of Multi role, Multi mission, and Medium weight Class helicopter

named Advanced Light Helicopter (ALH) (DHRUV).

2. Maintenance repair and overhaul division

Hindustan Aeronautics Limited (HAL) is looking at setting up a maintainance, repair and

overhaul (MRO) facility to leverage its Bangalore airport asset which is now closed to

commercial aircraft. The division will facilitate overhauling of air craft, manufacturing of

spare parts and engine assemblies.

3. Barrackpore Division

The present factory of Hindustan Aeronautics Limited (HAL), Barrackpore is engaged

with overhauling and repairing of small aircrafts. The factory is also a agency for civil

customer aircrafts. The factory is well supported with ground support/handling

equipment, test rig etc.,

4. Aircraft Research &Development Center

It mainly involves in development of Aircraft Design, Prototype Manufacturing, and

Extensive Testing Facilities and Design & development of Intermediate Jet Trainer&

Light combat aircrafts.

5. Rotary Wing Research and Development Center

It mainly involves in development of Design task for civil and military

Helicopters, Design Development & testing analysis of structure/transmission system&

integration of engine/avionics, Design development of DHRUV, ALH, LCH.

6. Composite Manufacturing Division

Composite shop is equipped with bonding fixtures and balancing aids. Composite shop is

equipped with facilities for lay-up composites and autoclave for curing fabricated

components. For manufacturing the various gears and component gear shapers, gear

hobbers.



CHAPTER-3

Evolution and growth of the company

Fig3.1 Growth of the Company



CHAPTER-4

ABOUT HAWK AIRCRAFT

PROJECTS

Over the last six decades, HAL has grown progressively into an integrated

aerospace organization with the indigenous design and development of Advanced Light

Helicopter, IJT and LCA (Tejas).

The ongoing major projects and programmes include ALH, IJT, LCA and Pilot less target

aircraft, SU-30MK1, and HAWK Advanced Jet trainer.

Hawk Mk 132 Aircraft

The British Aerospace Hawk is a light-attack and trainer similar to the Alpha Jet,

M.B.326, AMX, F-5 Freedom Fighter. Through a continuing update and modernization

program, the 20-year old Hawk is still known as one of the world’s best advanced trainers

and light-attack aircraft.

With the crew of two, if features low-mounted, swept-back wings that are tapered

with curved tips. One turbofan engine is located inside the body, with semicircular air

intakes alongside the body forward of the wing roots and a single exhaust. The top line of

the fuselage curves up from the pointed nose to incorporate the long clear cockpit canopy

then slopes down to the jet pipe, giving a humped appearance, with slighting-swept

vertical and horizontal tail surfaces. The maximum level speed of the Hawk is over 1000

km/h and the aircraft can attain supersonic speed (M1.2) in a dive.

In the current RAF training program, The Hawk T1is the first jet aircraft that a student

pilot will fly. An advanced and very successful trainer, Hawk is used to teach operational

tactics, air-to-air and air-to-ground firing, air combat and low-level operating procedures.

Fig 4.1 Hawk MK 132 Aircraft Fig4.2 Different Views of Hawk Aircraft



SPECIFICATION

Table 1: Specification

Country of origin UK

Builder British aerospace

Role Light attack trainer

Similar Aircraft Alpha Jet,M.B.326, AMX,F-5 Freedom Fighter

Wing span 31 ft. (9.42m)

Length 39 ft. (11.94 m)

Height 3.98 m (13 ft. 1 in)

Empty Weight 4,480 kg (9,880 lb.)

Engine One Rolls-Royce/Turbomeca Adour Mk 151 turbofan of

5200lb

Maximum speed 0.84 Mach (1,028 km/h, 638 mph) at altitude

Range 2,520 km (1,360 NM, 1,565 mi)

Service ceiling Hawk T1

One 30 mm Aden cannon pack and

Up to 5600 lb of under wing stores (rockets, bombs and

Missiles)

Armament T1 A- in addition has inboard pylons for

Sidewinder AIM-9 air to air missiles.



AIRCRAFT FACTS

The Hawk Advanced Jet trainer is a new aircraft, which has encapsulated 30 years

of experience with new systems to provide state-of-the-art training for the 21st century.

Principal features

Three, full color, Active matrix Liquid Crystal Displays, each controlled by soft

keys, and each able to display the full range of navigation, sensor, weapons and

systems data

Cockpit lighting fully compatible with the use of Night Vision Goggles, for

enhanced situational awareness during night operations

Head-up Display featuring symbology compatible with front line combat aircraft

types.

Hands-On-Throttle-And–Stick (HOTAS) controls with moding and switching

fully representative of front line combat aircraft types.

Inertial Navigation /Global positioning system for enhanced navigation weapon

aiming accuracy.

Health and usage monitoring system guaranteeing 10000 hours fatigue Life.

Rolls Royce/Turbomeca Adour Mk.951 turbofan engine (6500lb) with Full

Authority Digital Engine Control, with an impressive 4000 hours TBO (time

between overhaul).

Enhanced systems on the aircraft also include: -

An upgraded Electrical system, with power provided by a 25kVA generator

An Auxiliary Power Unit to provide electrical power and avionic cooling air

whilst the aircraft is on the ground. The APU also provides engine start and

engine re-light capability in flight.

An On –Board Oxygen generation system



Traffic Collision Avoidance System Ground proximity warning system

Digital Moving map

Auto pilot

Air to Air Refueling capability using a fully-detachable, fixed position probe

mounted ahead of the wind shield

Embedded weapons and sensor simulation allowing cost effective training to be

carried out on systems and tactics used on 4th

and 5th

generation front line aircraft.

Technical Data/Performance (indicative)

Length overall-40ft 7in(12.43m)

Wing span (with missiles)-32ft 7 in (9.94m)

Wing area-179.64sq ft (16.69 sq m)

Height overall -13ft 1 in (3.98m)

Basic Mass Empty -9792lb (4440 kg)

Maximum Take of weight -2069lb(9100kg)

Maximum level speed (at sea level)-555KCAS(.84M)

Maximum Dive speed-Mach 1.2

Maximum Load factors-+8g to -4g: +6g to -3g

Power plant-Rolls Royce/Turbomeca Adour Mk.951 turbofan engine with full

Authority Digital Engine Control, rated at 6500lb

Capability

Equipped with a moderately swept wing has a combat flap setting and ample reserves of

power from the Adour engine, the hawk is able to demonstrate exceptional flying



characteristics. The aircraft has an excellent turn rate in both clean and loaded

configurations and an impressive climb rate.

Throughout its flight envelope the Hawk demonstrates stable, carefree handling

characteristics with no control difficulties and therefore provides an exceptionally safe

training environments for pilots. The aircraft is equipped with the latest cockpit displays

and sensors and is able to demonstrate air to air and air to ground combat and tactical

formation flying and perform extended missions through the use of an air to air refueling

probe. Consequently, the Hawk is an ideal platform for the introduction of student pilots

in the Advanced Fast Jet phase of conversion.

The Hawk has tandem seats, with full controls available in the front cockpit. Duplication

of essentials controls with appropriate override facilities is provided in the rear cockpit,

for example store jettison, landing gear and flaps. Internal lighting is provided for

instruments displays, and general cockpit illumination. Cockpit lighting, instruments, and

displays are compatible with the use of night vision goggles (NVG).



CHAPTER-5

MISSION AND VISION

MISSION OF THE ORGANISATION

“To become a globally competitive aerospace industry, while working as an instrument

for achieving self-reliance in design, manufacture and maintenance of aerospace

equipment, civil transport aircraft helicopter and missiles and diversifying to related

areas, managing the business on commercial lines in a climate of growing professional

competence.”

VISION

“To make HAL a dynamic, vibrant value based learning organization with human

resources exceptionally skilled, highly motivated and committed to meet the current and

future challenges. This will be driven by core values of the company fully embedded in

the culture of the organization.”

QUALITY POLICY

To provide quality product and service to international standard resulting in total

customer satisfaction and to strive for continual improvement.

QUALITY OBJECTIVES

Conformance to approve specification/systems

Product review and improvement

To remain competitive in international market

To provide leadership to effect attitudinal changes in human resource

Customer training

Systematic selection of supplies.



CHAPTER-6

Principles and concepts of fixturing for CNC

machining centers

1. N.C. MACHINING CENTERS

An N.C. Machining centre has the ability to encompass many machine tools into one.

With this fact in mind the obvious extension of this newfound capability is to design and

build fixtures that will allow as many of these different operations to be performed in the

least number of setups. How N.C. affects the design of fixtures may be derived from the

principle of operation of these machines.

Briefly, an N.C. machine is positioned by accurate ball screws coupled to servo motors.

Feedback systems attached to these ball screws can measure the exact position to within

one tenth of one thousand of an inch (.0001). Therefore, the accuracy of machined part is

not reliant upon the operator but in the machine tool, the cutters and the fixture.

In N.C machining, the part remains fixed while positioning and motion is carried out

by the tool. The only purpose of fixture in N.C machining is to locate accurately and hold

the part rigid while the cutting tool is engaged in the work piece.

There are two types of machining centers which need to be categorized, one having a

horizontal spindle and a rotating work table, the other a vertical spindle. Both types of

machines incorporate automatic tool changing.



2. FIXTURE DESIGNING FOR NC

Programming NC machines in many cases is accomplished using the computer but it has

not yet become a reality in fixture design although successful implementation of

CAD/CAM systems have produced automated drafting, process planning, scheduling and

part design. Fixture designing for conventional machine relies on a thorough knowledge

of basic machining practice, previous hands-on experience and familiarity with machine

tools. Tooling up an NC machine with regard to fixtures requires the tool designer’s

normal requirements together with teamwork on the part of the process planner,

programmer and tool designer. Each must know what the other has in mind and before

final plans are made a sequence of events should be formulated as outlined in the

following procedure.

1. The process planner decides the basic method of manufacture and writes his process

sheets accordingly.

2. The NC parts programmer reviews these plans and indicates the size of material

required, pre-machined surfaces, stock allowances and his tooling requirements.

3. A basic layout of the proposed fixture is given to the tool designer by the programmer

which may show the locating surfaces, part clamping regions, clearance areas required,

and location of the fixture with respect to the machine tool. The tool designer should have

reference material showing the physical elements of the machine such as slide travels and

limits



CHAPTER-7

DEFINITION OF PROBLEM AND OBJECTIVES

DEFINITION OF PROBLEM

• Wear and Tear of the bolts were occurring due to the removal of bolts for the slot

allotted for pintle pin, because of which rework and re-drilling of those holes are

to be made in order to lock the pintle pin for landing gears.

• This rework takes a lot of human effort and the additional cost because of this

rework is much. Removal of bolts through hammer and knock punch takes a

minimum of 4 days and the diameter for these bolts are increased because of this

operation.

Fig7.1 Landing gear



Objectives

• We analyzed the problems faced during the removal of the bolts in the landing

gear pintle pin and we are designing and fabricating a small hand tool (Tool

extractor) through which these bolts are removed with ease without causing

damage.

• Because of which there would not be any rework has to be carried out further and

thereby reducing human effort and additional cost required for reworking thus

increasing efficiency and reducing manufacturing lead time.

• Apart from MOD 2459, Longeron requires Alignment pin for the size 4.67mm is

required for alignment of axis for drill jig on an inclined surface.



CHAPTER-8

DETAILS OF ALIGNMENT PIN

Fig8.1 ALIGNMENT PIN



CHAPTER-9

DETAILS OF LANDING GEAR PINTLE BOLTS REMOVER

LIST OF COMPONENTS

1. EXTERNAL SLEEVE

2. INTERNAL SLEEVE

3. SCREW ROD

4. FLANGE

5. SPACER

1. EXTERNAL SLEEVE

It is located in the external part of the tool. It supports the internal sleeve for

removing the bolts of the pintle pin.

Fig 9.1 External sleeve



2. INTERNAL SLEEVE

This is located inside the external sleeve. It slides in inside part of the external

sleeve and bolts are extracted through the tightening of this part.

Fig 9.2 Internal Sleeve

3. SCREW ROD

This part contains threaded portion of 92mm length from the free end and moves

inside the internal sleeve. This has the reverse nut mechanism through which the

bolts are removed.

Fig 9.3 Screw Rod



4. FLANGE

It is the part that supports the screw rod and in turn the internal sleeve. It acts as a load

bearing member and supports the sleeve the sleeve and screw rod.

Fig 9.4 Flange

6. SPACER Spacers are unthreaded sleeves that fit over bolts or screw to maintain space between

components.

Fig 9.5 Spacer



CHAPTER-10

ENGINEERING DRAWINGS

Alignment Pin

Fig 10.1 Drawings of Alignment Pin

Landing gear Pintle pin bolts remover

1. External Sleeve

Fig 10.2 Drawings of External sleeve



2. Internal Sleeve

Fig 10.3 Drawings of Internal sleeve

3. Screw Rod

Fig 10.4 Drawings of Screw Rod



4. Flange

Fig 10.5 Drawings of External sleeve

5. Spacer

Fig 10.6 Drawings of Spacer



CHAPTER-11

MATERIAL SELECTION AND ITS PROPERTIES

MATERIAL SELECTION: Mil-s-6758

MIL SPEC ALLOY TITLE OF MATERIAL

MIL-S-6758 4130 Steel, Chrome-

Molybdenum (4130) Bars

and Reforging Stock

(Aircraft Quality)

Table 2: Material Specification

Mil-s-6758 stands for Military Specification. The Tool Fabrication is done in the material

Mil-s-6758 which is used only in defence applications. It is mostly used in aircraft

industries for tool fabrication process by performing heat treatment process to attain its

required properties.

Abstract

Specifies chrome molybdenum (4130) aircraft quality forging stock and steel bars.

Coverage includes classification, manufacturing process, cleanliness, tolerances, chemical

composition, grain size, decarburization, tolerances, mill lengths, workmanship,

hardenability, and preservation and packing.

General Product Information

Scope

This specification covers chrome-molybdenum (4130) steel bars and forging stock of

aircraft quality.

• US MILTARY Specs/Standards Publisher

• FSC 0505 Committee

•MIL S 6758 Revision A Superseded by



Classification

The Steel bars and reforging stock shall be follows:

Physical Condition: Materials shall be furnished in one of the following physical

conditions, as specified

A. As forged

B. As rolled

C. Annealed

D. Normalized

E. Normalized and tempered

F. Hardened and tempered

Surface conditions: Materials shall be furnished in one of the following surface

conditions, as specified

1. Black, as forged or rolled

2. Pickled or blast cleaned

3. Rough turned

4. Cold finished (drawn)

5. Turned ground and polished.

REQUIREMENTS

1. Material

2. Quality: The steel shall be of aircraft quality.

3. Cleanliness: When inspected magnetically in accordance with the procedures,

material shall not exceed the size and frequency rating limits specified.

4. Manufacturing Process: The steel may be melted by one of the commercially

acceptable types of melting including open hearth, basic oxygen or electric arc

furnace. The steel may be ingot cast or continuous cast into billets. When

ingot casting, sufficient discard shall be made to secure freedom from piping

and undue segregation.

5. Physical/Surface Conditions: Unless otherwise specified in the acquisition

documents, bars 1.5 inches or less in diameter or thickness shall be furnished

in conditions and bars over 1.5inches in diameter or thickness shall be

furnished in conditions.

6. Tolerances: The permissible variation in dimension of bars, produced in

conformance with this specification, shall be as specified vin AMS 2251.



7. Workmanship: Material shall be sound, of uniform quality and condition,

free from pipes, and shall not contain laps, cracks, twists, seams, or other

defects detrimental to the fabrication or performance of parts.

Material Properties

• Mechanical properties

Strength, Ductility, toughness, hardness, strength to weight ratio etc.

• Physical properties

Density, specific heat, thermal expansion, conductivity, melting point.

• Chemical properties

Oxidation, corrosion, flammability

• Manufacturing properties

Formed, casting, machined, welding

Mechanical Properties

Yield strength at 0.2% offset

Tensile strength Psi(min) Extension

under load

inches per

inch

Elongation in 2

inches

Reduction of

area percent

125000 100000 .0107 17 55

Table 3: Mechanical Properties



Chemical Properties

Table 4: Chemical Properties

Physical Properties

Density : 283 Kg/m3

Specific Gravity: 7.8 kg/m3

Specific Heat : 0.114 KJ/kg K

Melting Point : 2610˚c

Thermal Conductivity :22.3 W/m2k

Mean Coefficient of Thermal Expansion:7 per ºc

Modulus of Elasticity Tension :29 N/mm2



CHAPTER-12

DESIGN OF FIXTURE

1. CUTTING FORCE CALCULATION

The axial cutting force induced during the end mill operation is given by the formulae

Fc = Pc x f x d----- newtons

Where

Pc = 2.5 to 4 times of tensile strength of material being cut, in N/mm2

f = Feed in mm/rev

d = Depth of cut in mm

Part material details

Material: Mil -s-6758

Tensile strength = 640 N/mm2

Pc = 4 x 640 = 2560 N/mm2

Cutting parameters

Cutting speed(s) = 2000 mm/min

Depth of cut (d) = 20mm (Half of the diameter of the end mill)

Feed (f) = Cutting Speed/ Speed = 2500/1000 = 2.5mm/rev

Cutting Force (Fc):

Fc = Pc × f × d

= 2560×2.5×32.5

Fc = 208000 N/mm2



2. Design of External sleeve

1. Fixture Material details

Material: Mil-s- 6758

Density: 7.85 g/cm3

Tensile strength = 640 N/mm2

Factor of safety = n = 2.5

Allowable bending stress (σb) = Tensile strength/ Factor of Safety

= 640/2.5 = 256 N/mm2

Bending moment Mb = Force × Distance

= 208000*40

= 8.32×106 N-mm

2. Bending Equation

=

=

Where

Mb= Bending moment

I = Moment of Inertia

σb = Bending stress

y = Distance of extreme fiber from neutral axis

E = Young’s Modulus of material

R = Radius of curvature

The thickness of external sleeve

Mathematically,

=√

= √

= 3.122mm

The thickness of external sleeve is designed to 5mm.



3. Design of internal sleeve

The internal sleeve is subjected to more compression load of 2, 08,000 N-mm

The design is based on direct compression load.

Allowable compressive stress of material = 256 N/mm2

Area of tapped hole

A1 = (π×d2×n)/4

= (π×272×4 )/4

A1= 2290.2mm2

Area of drilled hole for screw rod

A2 = (π×d2×n)/4

= (π×272×2)/4

A2 = 1145.1mm2

Bearing area required to sustain the compression load

A3 = Force / Stress

=2, 08,000/256

A3 =812.5 mm2

Total area as per the design

Area = A1 + A2+ A3

= 2290.2+1145.1+812.5

= 4247.8 mm2

The actual cross section area of internal sleeve is

Aactual= 1145.1*25

= 28,627.5mm2

Hence the design is safe.

The height of internal sleeve is designed to 65mm based on the accessibility of screw

rod.



4. DESIGN OF SCREW ROD

The design of screw rod is based on the compression strength of material, since it is

subjected to compressive load due to cutting force.

1. Compressive force acting on plate Fc = 208000

2. Allowable sleeve in plate (σ) =256/mm2

3. Area required to withstand stress (A1) = Force / Allowable stress

= 208000 / 256

=812.5mm2

4. Area required to accommodate bolt head (A2)

A2= ((π×d2×n)/4

= (π×182×6)/4

= 1526.81

5. Total area required (A)

A=A1 + A2

=1526.81+812.5

=2339.3mm2 = 2340mm

2

6. The width of the plate = 300mm and design is based on configuration of the part.

To find design thickness

Load bearing area A = width x thickness

2340= 300 x t

t =2340/300

t=7.8mm

By considering the stress for accommodating the bolt

Actual thickness = 10mm




CHAPTER-13

STRESSES INDUCED IN FINAL ASSEMBLY PART

Twisting moment

Mt= Bolt head radius× Force applied by operator

= 28×2

Mt =56 N-mm.

Polar moment of inertia

J=

=

J =79020.38mm4

Radius of external sleeve

r =

=

= 17mm.

Shear stress induced

τ induced =

τ induced = 0.118 N/mm2

σy = 435 mpa (yield stress of material)

τ allowable =

=

τ allowable= 217.5mpa.

τ induced < τ allowable




CHAPTER-14

JUSTIFICATION AND DIMENSIONS

Justifications for Alignment Pin

Mod-2459 kit is suitable only for pre-cold work.

Post cold work required size & dimension has not supplied.

Hence with new size and dimensions new pin is designed and fabricated.

Justifications for Bolts Extractor

Fig14.1 Exploded View

The main parts of this tool are Flange, spacer, External & internal sleeve, screw

rod

This tool is smaller in size so it can be used in lesser work space with

effectiveness.

Rework of bolt area is reduced by using this tool.



Dimensions with Tolerances

Table 5: Dimensions with Tolerances



METHODOLOGY



GANTT CHART



CONCLUSION

Hindustan Aeronautics Limited has world class infrastructure. They deal with

manufacturing of sophisticated products with ease. Although, they don’t have competitors

in the market, they maintain quality of the product.

They follow autocratic management with certain set of rules and principles. They deal

with current ear of globalization without harming the environment.

In this project work fixture has been designed and developed for “Alignment Pin and

Landing Gear pintle pin remover” used in HAWK aircrafts. Conclusion is to overcome

this problem we are designing alignment pin of the required dimensions necessary for

modifying the aircraft. This results in reducing the manufacturing lead time & the

addition cost required for rework.

In addition to above tangible benefits, the company stands to gain many intangible

benefits which includes, reduction in waiting time of tool component, reduction in rework

and defect, employee satisfaction and enhancing the reputation of the organization.

hindustan aeronautics limited overhual division, bangalore

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