Industrial Report

Report Writing

Industrial Visit to

Diesel Locomotive Shed

Haldirams

Maruti Suzuki India Limited

Tool Research and Training Center

Submitted by:

Abhishek Chhonkar (603/MP/09)

Deepanshu Bansal (621/MP/09)

Diesel Locomotive Shed

Acknowledgement

Our sincere thanks to the Diesel shed, Shakurbasti for providing the

invigorating experience. The way this colossal shed is run and managed

clearly shows the tremendous growth of the Indian manufacturing Sector

through the years.

We are also thankful to Mr. Pradeep Khanna, our faculty member for

organizing this crucial industrial visit. The entire experience of making this

report was fostering not only in intellectual, rational, academic facets but

also in practical and realistic facets.

Table of Contents

1. Maintenance of Diesel Locos

2. Stripping and Overhauling

3. Classification of Locomotives

1) WDS4

2) WDM2

4. Throttle Operation

5. Cooling

6. Lubrication

7. Transmission

8. Governor

9. Turbocharger

10. Braking System

1) Vacuum Brake

2) Air Brake

LOCOMOTIVES

A locomotive is a railway Vehicle that provides the motive power for a train. The word

originates from the Latin loco - "from a place", ablative of locus, "place" + Medieval Latin

motivus, "causing motion".

A locomotive has no payload capacity of its own, and its sole purpose is to move the train along

the tracks. In contrast, some trains have self-propelled payload-carrying vehicles. These are not

normally considered locomotives, and may be referred to as multiple units, motor coaches or

railcars. The use of these self-propelled vehicles is increasingly common for passenger trains

but very rare for freight . Vehicles which provide motive power to haul an unpowered train, but

are not generally considered locomotives because they have payload space or are rarely

detached from their trains, are known as power cars. Traditionally, locomotives pull trains from

the front. Increasingly common is push-pull operation, where a locomotive pulls the train in one

direction and pushes it in the other, and is optionally controlled from a control cab at the

opposite end of the train.

DIESEL SHED SHAKURBASTI

Diesel shed, Shakurbasti was established on 5th of April 1955 for preventive

maintenance of diesel locomotives. The shed at Shakurbasti has total area of 41141 sq. m but a

covered area of 15417 sq. m .It is a pioneer WDS4 shed of Indian Railways. It is the the oldest

maintenance shed in India. The first WDS-4A ('Indraprastha', #19057) is homed here but is due

to be decommissioned soon and sent to the NRM for preservation. This shed had some (16)

WDM-2 locos for a brief period, before they were sent on to Tughlakabad, Ludhiana, and

Bhagat-ki-Kothi sheds.

Bahamukhi” Diesel Shed, Shakurbasti of Northern Railway celebrated its Golden Jubilee

recently; it is making all efforts to keep up with the times with innovations and technological

development. From its humble beginnings in 1955, the Diesel Shed has evolved to become the

premier shed for diesel-hydraulic locomotives over Indian Railways. Showing its commitment

towards quality and environmental management, the Diesel Shed has acquired ISO 9001: 2000

and ISO 4001:1996certifications. This shed has also been entrusted with the maintenance of

140T Gottwald Cranes (Break-down Cranes). It is a matter of pride to state that it is the first

shed to successfully carry out trials on dual-fuel (CNG&HSD) on the DEMU. M/s IGL has

commissioned a CNG filling station inside the Railway premises, it is for the first time that a CNG

filling station has been erected on Railway premises.

The various Workshops/Production Units of the zone worked steadily towards better

maintenance practices during the year.

MAINTENANCE OF DIESEL LOCOS

Maintenance schedules:

The locos come here for maintenance according to the following schedule:

W5- schedule : After 2 months

Yearly schedule: After 3 years

A loco coming here passes through a number of inspections and safety tests

1. The fuel is drained out and the fuel system is checked.

2. Then some safety items like wooden blocks are placed below the loco’s wheels.

3. After that various parts of the loco electrical and mechanical systems are checked and

inspected manually and automatically (semi-automatic).

4. The lab parameters are verified for each loco and after that they are marked right or

wrong.

A new repair bay has been recently installed which can hold 6 locos at a time for repair,

maintenance & cleaning.

The general life span of a loco is 32-36 yrs and it needs around 4lts of fuel to run 1km.

Diesel locomotives can be viewed as an assembly of sub-systems. Whenever a sub assembly

requires maintenance attention which cannot be done on site or is time consuming, then it is

replaced with an operational unit. The removed unit is repaired, tested in a separate place and

kept ready for next repair needs. This is called Unit Exchange (UE) repair system and is widely

practiced in Indian Railways.

The UE systems are required during maintenance for the following cases:

a) Scheduled overhauling needs of the shed

b) Scheduled maintenance needs of the shop

c) Non-scheduled maintenance needs arising out of line failures

d) Non-scheduled maintenance needs identified during periodic maintenance

Stripping and overhauling:

Engine being overhauled

A sub-assembly sectioning is done and the various parts are checked for any repairs or defects

Pump section: Seal kits are changed. Levels of the consumables are checked. Proper

lubrication of the various parts is done.

Power pack (Engine): The dimensions of the connecting rods are checked for proper

clearance. The surface of the cam shaft is checked for any irregularities.

Cylinder Heads: Carbon deposits on valves are cleaned by dipping them in tanks. This is a

manual cleaning process. The valve seats are inserted in cylindrical head holes. Liquid nitrogen

is used to shrink fit these valves.

Engine Cylinders

CLASSIFICATION OF THE LOCOMOTIVES

(TYPES OF LOCOS)

Locos, except for older steam ones, have classification codes that identify them. This code is of the form

'[gauge][power][load][series][subtype][suffix]'

In this the first item, '[gauge]', is a single letter identifying the gauge the loco runs on:

1. W = Broad Gauge 2. Y = Meter Gauge 3. Z = Narrow Gauge (2' 6")

4. N = Narrow Gauge (2')

The second item, '[power]', is one or two letters identifying the power source:

5. D = Diesel 6. C = DC traction 7. A = AC traction 8. CA = Dual-power AC/DC traction 9. B = Battery electric(rare)

The third item, '[load]', is a single letter identifying the kind of load the loco is normally used for:

10. M = Mixed Traffic 11. P = Passenger 12. G = Goods 13. S = Shunting 14. L = Light Duty (Light Passenger?) (no longer in use) 15. U = Multiple Unit (EMU / DEMU) 16. R = Railcar (see below)

The fourth item, '[series]', is a digit identifying the model of the loco. Until recently, this series number was simply assigned chronologically as new models of locos were introduced.

There are basically two types of diesel engines used in locomotives which are preventive

maintained here:

1 WDS4

2 WDM2

A comparison between the two engines is given in the table below.

WDS4 WDM2

Light Duty Heavy duty

6-cylinder,700 HP,24V DC starting battery,450 RPM, mechanical governor

16 cylinder, 2400 HP,72 V DC starting

battery,1000 RPM, electrical governor

For Shunting purpose(mainly) For transporting freight & passengers

1. WDS4

The transmission of the engine is diesel-hydraulic. Initially only 10 no’s WDS4 locos were

imported from Germany. Initially holding capacity was for 50 no’s till 1987 and further

expansion of shed was done for holding of 100 locos in 1992 and the shed now has a total

holding capacity of 108 locos. Since the shed came into existence it has given different services

of WDS4 locos like passenger services in local areas, pilot, departmental, shunting within Delhi

and adjacent areas.

These locos are having MAK- Germany six cylinders, 700hp engine, with hydraulic transmission

like L-217 imported –KPC suri transmission with the latest voith transmission type L-4r2u with

improved design and higher speed.This shed is also earning by rendering Engg. Services to

public sector undertakings having 37 locos since 1979 & carrying out all major schedules upto

periodic overhauling with total satisfaction of customers.

2. WDM2

The transmission is diesel-electric. The WDM-2A is a variant of the original WDM-2. These units

have been retro-fitted with air brakes, in addition to the original vacuum brakes. The WDM-2B

is a more recent locomotive, built with air brakes as original equipment. The WDM-2 locos have

a maximum speed of 120 km/h(75 mph), restricted to 100 km/h (62 mph) when run long hood

forward. The gear ratio is 65:18.

DIESEL-ELECTRIC LOCOMOTIVE

Arrangement and Classification

A Diesel-electric locomotive is a locomotive propelled by electric traction motors geared to the

driving axles, the power for which is supplied by one or more electric generators driven by one

or more Diesel engines located on the locomotive. When the Diesel-electric locomotive throttle

is opened the main generators are connected automatically to the traction motors and electric

power flows to the motors to move the locomotive. As the throttle is opened wider the Diesel

engines speed up, delivering more mechanical power to the main generators and thus more

electric power is generated for the traction motors. When the throttle is wide open the Diesel

engines run at their maximum speed, and the power output of the main generators regulates

itself so that the traction motors are supplied with the required horsepower up to maximum

rating for any combination of speed and train load.

A locomotive consists of one unit, or two or more units operating in multiple. When operating in

multiple, the several units are under control from one operating cab. There may be two

operating cabs on a complete locomotive, one at each end, so that the locomotive may be

operated in either direction without turning.

Undergoing a major restoration which is going well, the loco is now completely dismantled and

the frames have been cleaned. The wheels will go away for repair soon. Motion being rebuilt and

the cab and bunker are being restored.

As the diesel engine rotates the centrifugal pump, oil is forced outwards at high pressure. The

oil is forced through the blades of the fixed guide wheel and then through the blades of the

turbine wheel, which causes it to rotate and thus turn the axle and the wheels. The oil is then

pumped around the circuit repeatedly. The disposition of the guide vanes allows the torque

converter to act as a gearbox with continuously variable ratio. If the output shaft is loaded to

reduce its rotational speed, the torque applied to the shaft increases, so the power transmitted

by the torque converter remains more or less constant.

Throttle operation

The prime mover's power output is primarily determined by its rotational speed (RPM) and fuel

rate, which are regulated by a governor or similar mechanism. The governor is designed to react

to both the throttle setting, as determined by the engineer (driver), and the speed at which the

prime mover is running. Locomotive power output, and thus speed, is typically controlled by the

engineer (driver) using a stepped or "notched" throttle that produces binary-like electrical

signals corresponding to throttle position.

Traction Motor

A traction motor is a type of electric motor used to power the driving wheels of a vehicle such

as a railroad locomotive, electrical multi-unit train (such as a subway or light rail vehicle train),

a tram, or an automobile. Traditionally, these are DC series-wound motors, usually running on

approximately 600 volts.

In diesel-electric and gas turbine-electric locomotives the horsepower rating of the traction

motors is usually 81% that of the prime mover. This assumes that the electrical generator

converts 90% of the engine's output into electrical energy and the traction motors convert 90%

of this electrical energy back into mechanical energy. Calculation: 90% x 90% = 81%.

Because of the high power levels involved, traction motors are almost always cooled using

forced air.

Cooling

Like an automobile engine, the diesel engine needs to work at an optimum temperature for best

efficiency. When it starts, it is too cold and, when working, it must not be allowed to get too hot.

To keep the temperature stable, a cooling system is provided. This consists of a water-based

coolant circulating around the engine block, the coolant being kept cool by passing it through a

radiator.

The coolant is pumped round the cylinder block and the radiator by an electrically or belt

driven pump. The temperature is monitored by a thermostat and this regulates the speed of the

(electric or hydraulic) radiator fan motor to adjust the cooling rate. When starting, the coolant

isn't circulated at all. After all, you want the temperature to rise as fast as possible when

starting on a cold morning and this will not happen if you a blowing cold air into your radiator.

Some radiators are provided with shutters to help regulate the temperature in cold conditions.

Lubrication

Like an automobile engine, a diesel engine needs lubrication. In an arrangement similar to the

engine cooling system, lubricating oil is distributed around the engine to the cylinders,

crankshaft and other moving parts. There is a reservoir of oil, usually carried in the sump,

which has to be kept topped up, and a pump to keep the oil circulating evenly around the

engine. The oil gets heated by its passage around the engine and has to be kept cool, so it is

passed through a radiator during its journey. The radiator is sometimes designed as a heat

exchanger, where the oil passes through pipes encased in a water tank which is connected to the

engine cooling system.

The oil has to be filtered to remove impurities and it has to be monitored for low pressure. If oil

pressure falls to a level which could cause the engine to seize up, a "low oil pressure switch" will

shut down the engine. There is also a high pressure relief valve, to drain off excess oil back to

the sump.

Lubricant Pump Lubricant Testing

Transmissions

Like an automobile, a diesel locomotive cannot start itself directly from a stand. It will not

develop maximum power at idling speed, so it needs some form of transmission system to

multiply torque when starting. It will also be necessary to vary the power applied according to

the train weight or the line gradient. There are three methods of doing this: mechanical,

hydraulic or electric. Most diesel locomotives use electric transmission and are called "diesel-

electric" locomotives. Mechanical and hydraulic transmissions are still used but are more

common on multiple unit trains or lighter locomotives.

Reverse Transmission

Diesel-hydraulic control (Wds4)

Diesel-hydraulic locomotives use hydraulic transmission to convey the power from the diesel

engine to the wheels. On this type of locomotive, the power is transmitted to the wheels by

means of a device called a torque converter. A torque converter consists of three main parts,

two of which rotate, and one that is fixed. All three main parts are sealed in an oil-filled housing.

The inner rotating part of a torque converter is called a "centrifugal pump" (or impeller), the

outer part is called a "turbine wheel" (or driven wheel), and between them is a fixed guide

wheel. All of these parts have specially shaped blades to control the flow of oil.

The centrifugal pump is connected directly to the diesel engine, and the turbine wheel is

connected to an axle, which drives the wheels.

Governor

A governor is a device used to measure and regulate the speed of a machine, such as an engine.

A classic example is the centrifugal governor, also known as the Watt or fly-ball governor, which

uses weights mounted on spring-loaded arms to determine how fast a shaft is spinning, and

then uses proportional control to regulate the shaft sped

.

Turbocharger

In internal combustion engines a turbocharger is a turbine-driven, forced-induction compressor

powered by the engine's exhaust gas.A turbocharger consists of a turbine and a compressor

linked by a shared axle. The turbine inlet receives exhaust gases from the engine causing the

turbine wheel to rotate. This rotation drives the compressor, compressing ambient air and

delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater

amount of the air entering the cylinder. In some instances, compressed air is routed through an

intercooler which cools the air before introduction to the intake manifold, as the reduced

density of hot air will cause a loss in power gained through turbocharging. The objective of a

turbocharger is; to improve upon the size-to-output efficiency of an engine by solving one of its

cardinal limitations

Turbocharger

Intercooler

An intercooler is used to cool the air entering the engine, hence increasing volumetric efficiency.

Intercooler

Dual braking system

These days dual braking systems involved in the locos like in wdm2

1 Vacuum brake

2 Air brake

Many locos these days have Dual Braking systems (both vacuum as well as air brakes). Vacuum

brakes were the older system, where vacuum is used for braking. However, this suffers from the

disadvantage that is not easy to detect leaks in the brake pipes. Air braking systems, on the

other hand, need to maintain a constant pressure in the pipes. Thus, any leak will be easily

detectable due to the sound (hiss) of the leaking air.

There are multiple options for braking. The most common ones, of course, are the A9 and the

SA9. These are levers in the WDM2 control stand as shown in the below image.

As is obvious, the train brake is for stopping the entire train, whereas the loco brake only gets

applied to the loco. Applying the loco brakes with an entire train behind it, when in motion, is

quite dangerous since it can cause banging and even derailment; the inertia of the coaches

behind would result in their banging into the slowed-down loco causing great harm.

Expressor (Combined compressor and exhauster) unit which produces the vacuum for the train

brakes as well as compressed air.

When the loco is started up, the brake pressure gauge should show 5 kg / sq.cm. Only then is

enough pressure built up throughout the brake pipe (connected across all the coaches) to

enable effective braking. The pressure is built up using a compressor. This also means that once

the loco is cranked up, the pilot needs to wait until the appropriate brake pressure is built up.

Further, if there is a (substantial) leak, the required pressure would fail to build up.

To brake, the pilot simply pulls the appropriate lever (train or loco) one notch at a time. As soon

as that is done, the brake pressure falls down.

Haldirams

Table of Contents

1. About Haldirams

2. Equipment and Machines Used

i. Rotary Head Extruder for Tedhe Medhe type snacks

ii. Potato Peeler Machine

iii. Potato Slicer

iv. Spice Coating Machine

v. Automatic Frying Machine

vi. Automatic Packaging Machine

ABOUT HALDIRAM’S

The Past

Haldiram’s began as a tiny shop in Bikaner, the land as famed for its saviouries as for its leather-

faced pipe players and fierce warriors. By 1982, Haldiram’s had set up shop in Delhi and the

capital had begun to stop by and take note of the saviours and sweets. It was word of mouth that

grew the business manifold over the next decade till Haldiram’s came to stand for a food

company that was synonymous with taste, hygiene and innovation.

USA was the first market we started exporting to, thanks to large indian population there. we

begun with about 15 products, all savouries, because they are favourite with Indians.

What began as a small town enterprise in india is today a global phenomenon. Haldiram is a way

of life for Indians no matter which country they live in. and the countries they live in are also

fast developing a penchant for these products.

The Present

Today,Haldiram’s is a 4 million dollar brand that,is a familiar sight on shelves across the USA,UK

and the Mddle East.Non Resident Indians carry back packets of Haldiram’s along with the

farewellls and nostalgia.And it is tha namethat they look for as they scan shops for familiar

scents and sights.

For over sixty years now,we have been unifying the palate of India.It has not been the simplest

of tasks; India speaks different tongues and has different taste buds to match.

However,today,we are a name that has become synonymous with taste and quality not only

within India but the world over.

Today Haldiram’s occupies considerable shelf space at prominent supermarkets the world

over.Tesco,Sommerfield and Carrefore.From traditionalIndian sweets and savouries to the more

international chips,cookies,nuts and sherbets,our products are fast capturing the imagination of

people making it possible for us to aim for deep penetrations in the Middle East,East Europe and

parts of North America.

EQUIPMENT AND MACHINES USED

1. Rotary Head Extruder for Tedhe Medhe type snacks

Description:

This Process is unique because every piece is varied in length and diameter

giving a homemade effect the texture of the product is very distinct. After it is

fried the product is crunchy in bite

Material is fed from the hopper.

Rotary head die with single/double cutter for cutting long/short size pieces

Power requirement is 18 HP.

Capacity 50-60 Kg per hour.

Floor space 6ft x 2 ft

2. Potato Peeler Machine

Description: This machine removes the skin from potatoes/peanuts(boiled), washed potatoes are

poured into the drum of the potato peeler from the top, the inner of the drum is coated

with abrasive carborundum, as the base of the drum rotates the potatoes strike against

the abrasive inner wall which removes the skin, this processing requires minor flow of

water through a pipe to remove the skin from the walls, the peeled potatoes are

removed from the side of the drum through a gate

MODEL 1 : PP14

Capacity : 7 Kg

Motor : ½ HP

Material : SS 304

3. Potato Slicer

Description: This is a self pressing type model; the potatoes are fed from the top of the machine. This

machine comes with three basic cutters, Plain chips, ripple chips, potato shreddings /

laccha / sully and French fries. Available in two models 250 kg per hr/400 kg per hr

model.

Model : PS250

Capacity : 250 Kg

Motor : ½ HP

Material : SS 304

4. Spice coating mixer

Description: Masala Mixing drum for Kurkure type snacks, Potato chips etc

Description:

This is specially designed to apply seasoning to fried product in uniform manner.

Capacity 10-15 Kg per batch of 8 min.

Motor Requirement 1 HP,3 Phase.

All Contact Part SS 304

Floor Space 3’*3’

5. Automatic Frying Systems

Description: Automatic Frying Systems Automatic Continuous frying systems available in different

models ranging from 80 kg per hr to 400 kg per hr, It is a direct fired system, it can use

diesel/LPG/Natural gas as fuel, the product is fed from one end and it comes out fried

from the other end by a conveyor system. It is deep fryer with submerged conveyor, It

can fry the following products o Namkeen (Indian savories)

Various pulses

Green pea snacks

Pellets

Extruded snacks

Coated peanuts, peanuts

6. Automatic Packaging Machine

Conveyer Speed: 5-8 m.min

Pouch Length: 5’’ – 30’’

Power Required: 220 VAC 50 Hz

Motor: 0.25/0.5HP single phase 220 VAC

Maruti Suzuki India Limited

ABSTRACT

In the following report we will be studying the growth of Maruti Suzuki India Limited and its contribution to the automobile industry in India. The report elucidates the methods adopted for product excellence, operational efficiency and customer intimacy and various production practices involved in the manufacturing of the vehicles.

ACKNOWLEDGEMENT

We want to take this opportunity to thank Mr. Pradeep Khanna for making

this trip to Maruti Suzuki India Limited possible and for accompanying us

on this trip and also solving our various queries.

We are also grateful to the professionals at Maruti Suzuki India Limited for

helping us get acquainted with the various manufacturing processes in the

industry.

TABLE OF CONTENTS

1. Introduction 2. MSIL’s Principal Objectives

3. MSIL’s Competitive Strengths

4. MSIL’s Supply Chain

5. Sales networkq

6. Marketing

7. Suzuki Quality Management System

7.1 Quality Improvement Initiatives

7.2 Kaizen

8. Maruti Production System (MPS)

9. Lean Manufacturing 10. Just in Time (JIT)

11. Manufacturing Process

11.1 Blanking and Pressing Shop

11.2 Weld Shop

11.3 Paint Shop

11.4 Assembly Shop

11.5 Machine and engine shops

11.6 Inspection

12. Preventive Maintenance

13. Conservation of energy

14. Research and Development 15. Conclusion

1. Introduction

Maruti Udyog Limited (MUL) was the result of the joint venture created in February 1981

between Japan's Suzuki Motor Company and the Indian Government when the latter decided to

produce small, economical cars for the masses. The intention of the venture was to produce a

'people's car'. It was on December 14, 1983 that MUL launched the first Maruti vehicle - the

Marti 800 priced at Rs. 47,500.

In late1980s, Suzuki increased its equity stake in MUL from 26% to 40% and further to 50% in

1992, converting Maruti into a non-government company. On 17 September 2007, Maruti

Udyog was renamed to Maruti Suzuki India Limited (MSIL). The company's headquarters

remain in Gurgaon, near Delhi. It is now a leading four-wheeler automobile manufacturer in

South Asia.

Maruti Suzuki has two manufacturing facilities in India, one in Gurgaon and the other in

Manesar, North India.

Gurgaon Facility The plant at Udyog Vihar, Gurgaon is spread over 1203364 square meters covering 396957

square meter area. This plant has 3 fully integrated production facilities with flexible assembly

lines. While these three plants have a total installed capacity of 350,000 cars per year, several

productivity improvements have enabled the company to manufacture nearly 650,000 cars per

year at the Gurgaon facilities. In fact on an average, one vehicle rolls out of the factory every 21

seconds and the plant has already rolled out over 6.5 million vehicles till date. The entire facility

is equipped with more than 150 robots, out of which 71 have been developed in-house. More

than 50 per cent of our shop floor employees have been trained in Japan.

Manesar Facility It is rated high among Suzuki's best plants worldwide and the plant was inaugurated in

February 2007. The plant has several in-built systems and mechanisms to ensure that cars

being manufactured here are of good quality. There is a high degree of automation and robotic

control in the press shop, weld shop and paint shop to carry on manufacturing work with acute

precision and high quality. In particular, areas where manual operations are hazardous or

unsafe have been equipped with robots. The plant is designed to be flexible: diverse car models

can be made here conveniently owing to automatic tool changers, centralized weld control

system and numerical control machines that ensure high quality. The open layout and

ergonomic design make work convenient and improve productivity.

The plant at Manesar is the company's fourth car assembly plant and has started with an initial

capacity of 100,000 cars per year. This will be scaled up to 300,000 cars per year. A total

investment of Rs 2,500 crore will be made in this car plant by 2010.

In March 2007, Maruti Suzuki India Limited crossed cumulative export figure of 4,50000

vehicles since its first export in 1986. It has exported vehicles to over 100 countries in 5

continents with 65% of total exports to the highly sophisticated and demanding European

Markets.

2. MSIL’s Principal Objectives

As the leading player in the small car segment of the Indian market, they have the following

principal objectives:

• To expand the size of the Indian market for small cars by strengthening and expanding the

dealer network and making automobile financing available at competitive rates

• To strengthen their leadership position in the small car segment of the Indian market

• To continue to benchmark themselves against improving global manufacturing, marketing and

other practices and standards, strive to increase customer satisfaction through quality products

and new initiatives, and promote the financial strength of their sale network.

3. MSIL’s Competitive Strengths

• Expertise in small car technology: As a subsidiary of Suzuki, they have access to globally

respected technology in the small car segment. They have the advantage of Suzuki’s expertise in

all aspects of small car technology and design, with respect to their products, manufacturing

processes and business practices, the development of their supply chain and the training of

personnel.

• Extensive product portfolio: They are the major manufacturer of cars in segment A

(priced below Rs.300,000). The Maruti 800 has been the largest selling car in India for several

years, and still continues to have the very high sales volumes. They also manufacturer three

distinct models, the Zen, the Alto and the WagonR, in segment B (priced between Rs. 300,000

and Rs.500,000). Their dominance in segment A and extensive product range in segment B

enables them to offer the customer a wider choice in the small car segment than any of their

competitors.

• Quality products: In November 2001, MSIL was one of the first automobile manufacturers

in the world to receive the ISO 9001:2000 certification. They benchmark their products against

international quality standards. They export their products to approximately 70 countries,

which are manufactured using the same assembly line as that for the domestic market.

• Extensive sales and service network: MSIL has the largest network of dealers and

service centers amongst car manufacturers in India In addition to the distribution of cars, their

dealership network is a critical resource in their efforts to provide customers with a “one-stop

shop” for automobiles and automobile related products and services such as automobile

finance, automobile insurance, Maruti certified pre-owned cars available for purchase, and

leasing and fleet management, in order to promote customer loyalty.

• Brand strength: MSIL is present in the Indian market for almost 24 years and have built the

brand on the basis of the values of trust and reliability In 2000, 2001 and 2002, J.D.Power Asia

Pacific, Inc. ranked MSIL the No. 1 in the India Customer Satisfaction Index, which assesses

customer satisfaction with product quality and dealer service. NFO Automotive’s 2002 Total

Customer Satisfaction Survey ranked Maruti products as No. 1 in the “Economy”, “Premium

Compact” and “Entry Midsize” segments respectively, for 2002.

• Integrated manufacturing facility: Their manufacturing facility consists of fully

integrated plants with flexible assembly lines located at Gurgaon. The facilities have advanced

engineering capability and each plant is upgraded on an ongoing basis to improve productivity

and quality. They are one of the most efficient among the vehicle manufacturing facilities of

Suzuki’s subsidiaries outside Japan in terms of productivity measured as the ratio of number of

vehicles produced to number of employees.

• Strong vendor base and higher rates of localization: In order to improve quality and

generate economies of scale, MSIL has reduced the number of vendors of components in India

from 370 as of March 31, 2000 to about 100 as in 2005. As of the same date, they had strategic

equity interests through joint venture agreements in their vendors, who together supply a

substantial portion of the purchases of components. A number of their vendors are their

dedicated suppliers in that they account for a majority of their turnover. Vendors located within

a radius of 100 kilometers from the facilities supply the majority of the components. The

production systems of their vendors are generally aligned to their needs for a reliable and

timely supply of components that meet the required quality standards. This has enabled MSIL to

increase the proportion of locally sourced, lower cost components in their models, a concept

refer to as localization.

4. MSIL’s Supply Chain

MSIL’s inputs primarily comprise raw materials and purchased components. Only a small

amount of raw material and components consumed are imported and a much larger portion is

purchased from the sources within India.

Raw Material Suppliers

The raw materials used in the manufacturing process primarily comprise steel coils and paints.

In recent years, MSIL is increasingly trying to localize the purchases of steel coils with a view to

reduce cost. Earlier MSIL used to follow the tender system for the purchase of steel. Under this

system, specifications were advertised and accept the lowest price offered by a supplier who

could meet the specifications. In 2001 MSIL moved to the quotation system which gives them

the flexibility to renegotiate the prices once an offer is submitted. Standard purchase orders are

issued covering a period of six months for purchase of steel from foreign suppliers for Indian

supplier the period extends up to one year. At MSIL the role of the vendors has gradually

evolved from tactical to strategically where the vendors work in close coordination with MSIL to

meet our long-term goals in terms of:

• component development;

• quality;

• delivery

• cost control.

In order to improve quality and generate economies of scale, MSIL has reduced the number of

vendors of components in India from 370 as of March 31, 2000 to about 100 as in 2005. In case

of repair and replacements, costs of defective components supplied are borne by the vendor.

Delivery by Vendors

MSIL has a delivery instruction system that provides details of the component requirements for

every 15 days, across the different variants of the various models, to the vendors. Vendors are

linked to the MSIL through the Internet-based information network, which maintains online

information regarding order status and delivery instructions. These has helped in reducing both

inventory levels and lead times required for the supply of various components and sub-

assemblies, and enable the vendors to more efficiently plan and dispatch their products.

Vendors located within a radius of 100 kilometers from the manufacturing facility supply the

majority of the components. This has enabled the vendors to eliminate packaging and supply

components directly to the assembly line.

Reduction of Vendor Costs

In some of the major vendors MSIL has implemented the MPS, which focuses on the elimination

of wasteful activities in its manufacturing processes. Vendors are helped in areas such as

improving their productivity, reducing the number of their components that are rejected,

reducing materials handling, improving their yield from materials, and reducing their

inventories. This helps reduce their costs of production, and also reduces the costs of the

components required.

Vendor Quality Control

Quality management system such as ISO 9000/ QS 9000 forms the basis for producing a quality

product. To assist small and medium vendors in achieving ISO 9000 certification, in 1995 MSIL

adopted a cluster approach wherein vendors are grouped together, are trained in quality

management and are assisted in obtaining ISO 9000 certification. This cluster approach was

extended to helping vendors attain QS 9000 certification. Periodic vendor quality system audits

are conduct in order to ensure that quality standards are sustained.

Imported components

Imported components are mainly purchase from Suzuki.

5. Sales network

Dealers

MSIL has the largest network of dealers amongst car manufacturers in India. As of March 31,

2003, dealers had employed more than 3,500 sales executives. Sales network is linked with the

MSIL through the secure extranet-based information network. The sales of spares, accessories

and Automobile-related services such as insurance and finance serve as additional sources of

revenue for the dealers. The availability of these related products and services at sales outlets

also helps to attract customers to the outlets and promotes sales of the cars.

Agreements with our dealers

MSIL dealers provide services to customers such as pre-delivery inspection of vehicles, sales of

cars, after sales service, supply of spare parts and other services that promote sales of cars

within the territory for which they are appointed. Dealers are required to maintain their outlets

in accordance with the specifications and employ well-trained sales staff. Agreements with the

dealers are usually of five years. These agreements are generally renewable for successive

terms of three years, by mutual agreement.

Enhancing dealer performance

The performance of the dealers is followed and improvements are suggested frequently. In

order to assist the dealers in enhancing their performance and capabilities, MSIL has introduced

a concept of “Balanced Scorecard”. Using this tool, the performance of a dealership in several

areas of operations, including sales, service, spares and accessories, financial management and

management systems is measured. Dealers who perform well on the “Balanced Scorecard” are

reward with a cash payment at the end of the fiscal year. The “Balanced Scorecard” serves as an

effective incentive for dealers to enhance their performance.

After-sales Service Network

There are more than 400 Maruti dealer workshops and more than 1,500 Maruti Authorized

Service Stations, or MASSs, covering more than 900 cities in India. In addition, 24-hour mobile

service is also offered under the brand “Maruti On-road Service”. As a benchmark for dealers

with respect to service quality and infrastructure facilities, MSIL has launched service stations

under the brand “Maruti Service Masters, or MSMs. MSIL also has service stations on highways

in India under the brand “Express Service Stations”. To promote sales of spare parts and the

availability of high quality, reliable spare parts for its products, spares are sold under the brand

name “Maruti Genuine Parts”, or MGP. These are distributed through the dealer network and

through the authorized sellers of the spare parts. Many of the MASSs are at remote locations

where MSIL do not have dealers. In order to increase the penetration, in terms of sales volumes,

of its products in these remote areas, some of the MASSs are integrate into the sales process in

order to increase sales of the cars and related products and services such as spares and

accessories, insurance and financing.

6. Marketing

Maruti’s marketing objective is to continually offer the customer new products and services

that:

• Reduce the customer’s cost of ownership of our cars

• Anticipate and address the customer’s needs and preferences in all aspects and stages of car

ownership

MSIL has been aggressively cutting prices of its models since the beginning of the year. The

rationale behind the price cuts is the focus on offering new upgraded vehicles at a low price.

7. Suzuki Quality Management System

Based on a method adopted by Suzuki at its manufacturing facilities, the quality of a vehicle

dispatched from their facility is measured through a quality index audit on a daily basis. The

quality index is a relative measure of quality based on evaluation of vehicles selected at random

on a daily basis.

7.1 Quality Improvement Initiatives

For quality control Maruti had recently introduced:

• Tracking surveys and direct customer contact in order to better understand customer

satisfaction levels and customers’ problems.

• Full-time task forces for improvement in initial quality study problems and departmental

cross-functional teams to work on defined problems with challenging targets.

• Quality gates at various stages in order to raise alarms for correction and immediate action on

defects;

• Fool-proofing, or Pokayoke in Japanese, which comprises checks conducted in order to

prevent defects arising from human error during the manufacturing process; A real-time

feedback system, cross-linked with overall targets.

• The “Pica Pica” system, which aligns the sequence of components and vehicles in order to

prevent incorrect fitting of components.

7.2 Kaizen

Maruti had adopted the Japanese management concept of Kaizen, or continuous improvement.

The Kaizen activities had resulted in the improvement of the in-house capabilities. For example,

they had manufactured 25 multi-axis robots and 16 multi-spot welders. Group discussions

among employees in different departments are conducted on a monthly basis in order to discuss

and resolve problems relating to their areas of operation, an activity referred as quality circle

activity. Based on the belief that individuals contribute to improvement in growth, there has

been a suggestion scheme in which they promote participation of all employees at all levels. The

average number of suggestions made per employee has improved by approximately 35% in

fiscal 2004, when suggestion received were more than 80,000, as compared to fiscal 2002. Some

of the other improvements as a result of the Kaizen process have been increased automation

through automated material transport system.

8. Maruti Production System (MPS)

MPS is a systematic approach to eliminate Muri's (inconveniences if any for shop floor employees) Mudas (all forms of wastages) and Muras (inconsistencies in quality) from the system so that cost, quality, productivity and safety are under control. Under the Maruti Production System (MPS), derived from the Suzuki Production System, Maruti engineers captured all aspects of operation on video and scrutinized each process to identify wastage. Together with workers on the shop floor, layouts were altered, innovative equipment and processes were introduced and operations relentlessly made lean and efficient.

According to MPS, there are eight types of wastages in any process namely, Idle Time Inventory Over Production Production Defects Unnecessary man movement Unnecessary material movement Unnecessary inspection Unnecessary processing

However, if every employee tries to do the job right the first time, wastages due to unnecessary

inspection and processing are eliminated from the system and it is a cost effective approach.

9. Lean Manufacturing Lean Manufacturing is the optimal way of producing goods through the removal of waste and

implementing flow or smoothness of work.

The concept of Lean Manufacturing was adopted by their parent company Suzuki Motor

Corporation (SMC). Lean Manufacturing ushered a new era in the world of manufacturing. As

opposed to the mass manufacturing approach lean manufacturing is all about high quality and

high flexibility. As a philosophy Lean Manufacturing is widely acclaimed for its focus on

eliminating wastes of all kinds.

10. Just in Time (JIT)

JIT is an inventory strategy implemented to improve the return on investment of a business by

reducing in-process inventory and its associated carrying costs where everything from

procurement of raw material to dispatching of final product is done just at the time of

requirement.

This means that stock levels of raw materials, components, work in progress and finished goods

can be kept to a minimum. This requires a carefully planned scheduling and flow of resources

through the production process. Modern manufacturing firms use sophisticated production

scheduling software to plan production for each period of time, which includes ordering the

correct stock. Information is exchanged with suppliers and customers through EDI (Electronic

Data Interchange) to help ensure that every detail is correct.

11. Manufacturing Process

The manufacturing process at Maruti facility is depicted below:

Fig 1: Arrangement of various facilities in Maruti Suzuki Plant

Each of the shops had a product type of layout. In this type of layout machines are arranged in

order of sequence of operation. Product Layout is suited for mass or continuous production and

its advantage are that the cost per product is less and work in progress inventory is less.

Utilities

Maruti do not have to rely on outside sources of power as they have a 60-megawatt gas turbine

captive power plant, which has multi-fuel capability. They also have our own reverse osmosis

water treatment plant and effluent and sewage treatment plant.

11.1 Blanking and Pressing Shop Blanking is the operation of punching, cutting, or shearing a piece out of stock to a

predetermined shape and size by die cutting the outside shape of a part for the next operation

such as pressing, drawing and forming.

Pressing is the process of giving blanks required shapes with dies and presses.

Fig 2: Steel coils converted into steel sheets.

The press shop has five transfer presses and two blanking lines. In the press shop, steel coils are

cut to the required size and panels are prepared by pressing them between various die sets such

as doors, roofs and bonnet. An anti-rust coat is applied at this stage.

This plant uses 400 tonne presses to press the blanked sheets. There are six passages with a

capacity ranging from 1000-4000 tonnes. The plant is capable of producing pressed sheets for

all the ten models manufactured by Maruti Udyog Ltd.

They have in-house capability and the necessary technical knowledge for the design and

manufacture of medium-size press dies.

11.2 Weld Shop

Spot welding is a type of resistance welding, which is a method of welding two or more metal sheets together without using any filler material by applying pressure and heat to the area to be welded. It is used to weld various sheet metal products. Typically the sheets are in the 0.5-3.0 mm thickness range. The process uses two shaped copper alloy electrodes to concentrate welding current into a small "spot" and to simultaneously clamp the sheets together. Forcing a large current through the spot will melt the metal and form the weld. The attractive feature of spot welding is a lot of energy can be delivered to the spot in a very short time (ten to one

hundred milliseconds). That permits the welding to occur without excessive heating to the rest of the sheet.

Fig 3: Spot Welding

There are three welding shops with 122 six-axis robots and 25 in-house manufactured two-to-

four axis robots. In this shop, various press metal components manufactured in the previous

stage are spot-welded together to form the body shell. Various parts such as the floor panel, side

panel, doors and bonnet are sub assembled in this shop. Subsequently, the assembled parts

undergo final welding. The welded body is sent to

the paint shop through a conveyor.

Fig 4: Different car parts are welded Fig 5: Weld Shop

11.3 Paint Shop

There are three paint shops, within one of which the final outer body is fully painted by robots.

In the paint shop, the body undergoes various pre-treatment and electro deposition painting

processes to provide a high corrosion resistance to the body. The car body is given an

intermediate or primer coat before applying the storing topcoat paint. The intermediate and the

final coat are applied by using automatic electrostatic spray-painting machines and robots,

followed by a baking process.

Due to the risk of inhaling poisonous fumes in the Paint Shop no one is permitted inside the

shop without proper safety equipment. The paint shop consumes about 7 hours because the

conveyor is a few kilometres long. At the end of the paint shop the painted shell is taken to the

assembly shop.

Fig 6:

1st coat of paint to make 2nd and 3rd coat of paint Final inspection of the

it stain and rust proof on the vehicle body. painted vehicle.

11.4 Assembly Shop

Maruti has highly flexible assembly lines, which can simultaneously handle a large number of

variants as well as adapt to sequence changes. The painted bodies proceed for final assembly in

three stages. Doors are covered with coverings to prevent scratches on painted car body. The

first stage is the trim line wherein various components such as roof head lining, windshield

glass and interior trim components are fitted. Thereafter, the car is transferred to an overhead

conveyor, the chassis line, wherein components such as the engine, gearbox and front and rear

axles are assembled on the underbody. The vehicle is then lowered to the final line on its own

wheels and here components and parts such as seats, the steering wheel and the battery are

fitted. These are done manually and the painted car moves on a conveyor belt at ground level. At

each work station parts being assembled come on a line perpendicular to the conveyer. The

conveyor is raised to appropriate heights for the workers’ comfort to increase their efficiency.

The completely assembled vehicle finally rolls out of the assembly lines to the final inspection

stages.

11.5 Machine and engine shops The various raw materials for engine components are machined using automatic machining

centres and these machined parts are assembled together to make engines. Assembling and

testing of engines takes place at engine shops and precision machining of engine components is

carried out in the machine shops.

Fig 7: Engine assembled from different components

11.6 Inspection

Sample inspection is done i.e. in a lot only a few samples are inspected. Following tests are done

to inspect the manufactured car:

i) shower test ii) headlight test iii) brakes test iv) speed test v) test drive on test track

Shower testing is done by spraying water from all sides to check for leakages. For checking

wheel’s speed the car is raised above the ground and then is operated at different speeds and on

different gears. The car is driven on a test track which consists of different terrains to check

performance of car under different conditions.

Fig 8: Inspecting brakes Fig 9: Emission Checks

If any defect is found, then all cars up to the last cleared car are checked again for defects and

remedial actions are taken. The cars are then parked in the final vehicle parking area before

dispatching.

Fig 10: Handover the vehicles for sales and dispatch

12. Preventive Maintenance Preventive maintenance is a schedule of planned maintenance actions aimed at the prevention

of breakdowns and failures. The primary goal of preventive maintenance is to prevent the

failure of equipment before it actually occurs. It is designed to preserve and enhance equipment

reliability by replacing worn components before they actually fail. Preventive maintenance

activities include equipment checks, partial or complete overhauls at specified periods, oil

changes, lubrication and so on. In addition, workers can record equipment deterioration so they

know to replace or repair worn parts before they cause system failure. Recent technological

advances in tools for inspection and diagnosis have enabled even more accurate and effective

equipment maintenance. The ideal preventive maintenance program would prevent all

equipment failure before it occurs.

Long-term benefits of preventive maintenance include:

Improved system reliability. Decreased cost of replacement. Decreased system downtime. Better spares inventory management.

13. Conservation of energy

Maruti had followed the three principles of “Reduce, Reuse and Recycle” for conserving energy.

Between fiscal 1997 and fiscal 2004, they had reduced the consumption of electricity measured

as the ratio of kilowatt hours of power consumed to the number of vehicles produced, by

approximately 35%. This was achieved by using energy saving lights and natural light, and also

the efficient usage of other electrical appliances, thus reducing wastage. In the same period,

reducing the consumption of water, measured as the ratio of the volume of water consumed to

the number of vehicles manufactured, by approximately 70%. This is achieved through the

recycling of wastewater in their water treatment plant and effluent and sewage treatment plant.

14. Research and Development

R&D activities of Maruti have the twin objectives of reducing product costs by developing

capabilities of local vendors and becoming a regional R&D hub for all Suzuki operations. The

company has adopted a ‘focused model cost reduction’ technique. Maruti has been continuously

engaging in Value Analysis/Value Engineering (VA/VE) activities across its operations. Some

areas in which MSIL carry out research and development is localization and development of

components, cost reduction measures such as

VA/VE, development of alternate fuel (CNG and LPG) vehicles, performance- benchmarking to

certain parameters such as noise, ride handling and braking and development of power-steering

for certain models. MSIL regularly upgrade its models and also launch variants by adding

features developed through research and development. All this has resulted in significant

reduction in the investment required for the modifications.

15. Conclusion

The industrial visit to Maruti Suzuki India Limited was very informative and gave us a fair idea

of the steps involved in the manufacturing of a car. It was very impressive to see the amount of

automation being used in the industry. It showed us how production, maintenance, inspection,

inventory control, demand forecasting all operated simultaneously and with high efficiency. It

was heartening to see practical application of a lot of our course content. To sum up we can say

that the trip improved our knowledge and helped us to understand the working of a large-scale

production unit.

Tool Room and Training Centre

ACKNOWLEDGEMENT

We want to take this opportunity to thank Mr. Pradeep Khanna for making this trip to Tool

Room and Training Center possible and for accompanying us on this trip and also solving our

various queries.

We are also grateful to the professionals at TRTC for helping us get acquainted with the various

manufacturing processes in the industry.

INTRODUCTION

Tool Room & Training Centre, Delhi was established in 1976 with Technical and Financial

Assistance of Govt. of Denmark with Govt. of Delhi. In short span of two decades the Centre has

emerged a pioneer in its efforts to create an indigenous technical base suitable to the industry.

The Centre concentrate on two vital fields i.e. Training of Technical hands & Manufactures of

sophisticated Tools and in each tangible results have been achieved by the Centre.

The Tool Room Training Centre (TRTC) is situated in the Wazirpur Industrial Area Covering an

area of approximately 3.5 Acres.

They started with short term courses but now have expanded to a larger extent. They guarantee

100% placements through college.

In today’s date the courses include: short term courses, CADCAM, Advanced-Working in tool

room (highly skilled). Courses may be fortnightly, monthly or yearly. i.e.

1. Design & Manufacture of Tools & Dies, Gauges, Jigs & Fixtures

2. Undertaking Project Assignment

3. Free Consultancy in the field of Product Development, Product Manufacturing, Tooling & Setting of projects

4. Processing of Plastic & Sheet metal Components

5. Training of Tool Designers, Tool Makers, Tool Room Machine Operator & Tool Fitters

6. Providing training on CAD/CAM & Computer Application

They are in the process of changing their name to DITE (Delhi Institute of Technical

Engineering) in the year 2008.

TRTC is divided into two Departments viz. Training and Production departments. They have

CNC and other specialized machines for training.

We were assisted by Mr Singhal( Production officer ), Mr Sharda( Training officer ), Mr

Seghal(Dy.Manager (TMT)) and Mr R.D Sharma(Asstt. Manager (TMT)).

At the starting we were given an introduction of the different courses offered for M-Tech ( 2

years AUTOCAD) and for Training (4 years for Post Graduate for tool design and 1 year

Advanced course for ITI students). Short term courses included Tool Making and Mould Making.

We were divided into two groups of 13 each. Our group was escorted by Mr Singhal towards the

Production department.

Cylindrical Grinding Machine

We were shown a Cylindrical Grinding Machine. It is a machine tool used for producing very fine

finishes or making very light cuts, using an abrasive wheel as the cutting device. This wheel can

be made up of various sizes and types of stones, diamonds or of inorganic materials. Cylindrical

grinders are a class of grinding machines used on the work pieces that are symmetrical about

an axis of rotation (e.g. cylindrical).

It is basically a Lathe machine, the only difference being that, in Cylindrical grinding only the

surface is grinded.

It can be used for both internal and external grinding i.e internal grinding is done for holes and

external grinding may be used for surface grinding purposes. Very fine surface finish is obtained

which is an advantage over Lathe machine.

Usually, the work piece is held between centers or chucked and rotated against a faster spinning

grinding wheel.

Here, both the job as well as the work piece rotate about there respective axis. Accuracy as well

as surface finish are characteristics of the work pieces grinded using Cylindrical grinding

machine. Accuracy of about 5 microns is obtained in cylindrical machine.

Surface grinder

We were shown a Surface grinding machine which makes use of a magnetic bed for placing the

work piece steadily. A Surface grinder is a machine tool used to provide precision ground

surfaces, either to a critical size or for the surface finish. The magnetic field of the bed changes

its polarity by just pulling and pushing a lever. Magnetic bed used is to facilitate the holding of

the job, as clamps or vices cannot be used.

Grinding wheel rotates and the job moves left and right on the press of a button. Wheel is made

up of aluminium oxide for softer metals and of silicon carbide for harder metals.

Diamond dresser is used to re sharpen the rotating wheel surface. This is done to get a new

surface of aluminium or silicon carbide for grinding.

Milling machine We visited the Milling section used for precision work. A Milling machine is a machine tool

used for the complex shaping of metal and other solid materials by removing material using a

multipoint cutting tool.

Types of milling machines:

1. Plain milling machine 2. Universal milling machine 3. Omniversal milling machine 4. Plano miller 5. Vertical milling machine

Its basic form is that of a rotating cutter or endmill which rotates about the spindle axis (similar

to a drill), and a movable table to which the workpiece is affixed. Machine’s accuracy is high

within 20 micron accuracy. Here Vice is used for holding the job to be milled. The job is fixed

and the cutter rotates in clockwise direction. The table can be moved in 3 directions.

Instead of a driller, a cutter is used to make the surface of the job flat. The job moves

horizontally. It is different from filing in accuracy and speed.

Jig grinding

A Jig grinding machine was shown to us which is used for grinding complex shapes and holes

where the highest degrees of accuracy and finish are required. Here the job is stationary (

clamped on the bed ) and the parazon wheel ( made from sintering process ) experiences two

types of rotating motions, one about its own axis, and other cylindrical motion about the central

axis of the work piece hole. The head of the wheel oscillates vertically too, so as to cover whole

length of the job for grinding.

It is used for both internal as well as outer surfaces, accuracy is high and thus cost is higher.

Electrical Discharge Machining

EDM refers to Electrical Discharge Machinery. The complex shapes which cannot be made

using conventional machines are made by electrodes. Basically EDM is a machining method

primarily used for hard metals or those that would be impossible to machine with traditional

techniques.

Sometimes referred to as spark machining or spark eroding, EDM is a nontraditional method

of removing material by a series of rapidly recurring electric arcing discharges between an

electrode (the cutting tool) and the workpiece, in the presence of an energetic electric field.

We were shown some complex shapes made by EDM that could have been really difficult to

make otherwise. Female or even Male parts of certain couplings may be sometimes difficult to

make due to reduced accessibility.

Graphite or Copper may be used for making the electrodes. Conventionally Hardened steels are

difficult to machine, but EDM can even machine H.S very easily.

The EDM cutting tool is guided along the desired path very close to the work but it does not

touch the piece. An arc is created due to the high voltage, due to which the material of the work

piece gets eroded away and thus a profile of the electrode is created on it gradually.

Consecutive sparks produce a series of micro-craters on the work piece and remove material

along the cutting path by melting and vaporization. The particles are washed away by the

continuously flushing dielectric fluid. The dielectric fluid also helps in the conduction of the

discharge from the electrode to the work piece. Water is best for this purpose but not used due

to its corroding property.

The electrode is made negative and the work piece as positive during the whole process.

It is a gradual process and is automatically switched off when whole impression is transferred.

A micrometer is used for this purpose. As the process continues, the micrometer moves

downward ( very slowly ), and when it reaches the bottom the machine automatically switches

off.

In this process, the current values should be adjusted accurately. Too high current does finishes

the work in short duration but reduces the surface finish. So current is generally reduced so as

to obtain a finely finished job.

Some of the disadvantages of EDM include the inability to machine non conductive materials,

the slow rate of material removal, and the additional time and cost used for creating electrodes.

Inspection Department

This section at TRTC was utilized for checking the finished jobs and then machining them as per

requirement. For this purpose a Profile Projector is used.

Magnification can be adjusted manually in a profile projector. The work piece is placed below

the lens and a highly magnified image is formed on the horizontal screen. A master is made by

enlarging on a butter paper or trace paper so as to check any irregularities present in the piece.

Then the work piece is subjected to further machining ( if possible ), and again checked under

the projector. This cycle is repeated until and unless the required dimensions of the job are

achieved.

We were shown a Height Master for measuring the diameter of holes. For that we had to first

touch the bottom of the hole with the tip of the instrument and set it to zero. Then the tip is

moved vertically upward by rotating the scale, and the movement is stopped as it touches the

top. The instrument displays the distance moved vertically on the LCD. It is basically used for

fast inspection purposes.

Another form of Height Master, connected to an external digital counter was also shown. The

purpose was same as that of the previous one but the arrangement was different.

Its demonstration was given in order to find the height of a work piece.

Rockwell Hardness Machine

Hardness is the property of a metal, which gives it the ability to resist being permanently,

deformed (bent, broken, or have its shape changed), when a load is applied. The greater the

hardness of the metal, the greater resistance it has to deformation.

The Rockwell Hardness test is a hardness measurement based on the net increase in depth of

impression as a load is applied. Hardness numbers have no units and are commonly given in the

R, L, M, E and K scales. The higher the number in each of the scales means the harder the

material. The indenter may either be a steel ball of some specified diameter for softer materials

or a spherical diamond-tipped cone of 120° angle and 0.2 mm tip radius, called Brale. The type

of indenter and the test load determine the hardness scale(A, B, C, etc).

A minor load of 10 kg is first applied, which causes an initial penetration and holds the indenter

in place. Then, the dial is set to zero and the major load is applied. Upon removal of the major

load, the depth reading is taken while the minor load is still on. The hardness number may then

be read directly from the scale.

Rockwell hardness number is the difference in depths of the indentations made by applying the

major and 10 Kg minor load, measured after removing the major load.

Note: In the above figure, Rockwell hardness number = ‘e’

CNC (Computer Numerical Control)

It was used in order to control a milling machine. There was no manual control involved. The

only section that required skill was ‘programming the CNC’ (which is done beforehand and the

work piece then moves in x, y and z directions with respect to a reference point). A cast iron

table was used for placing the job which is then clamped to it. The x, y and z values were

displayed on the monitor. Accuracy of the machine was about 20 microns.

Lathe Machine

A lathe is a machine tool which spins a block of material to perform various operations such as facing, turning, centre drilling, tapered turning, step turning, eccentric turning, grooving, form turning, external threading, knurling, parting off, chamfering, drilling, reaming, boring, internal thread cutting, trepanning, filing, spring winding, counter boring, counter sunking and undercutting using a single point cutting tool. There are basically different work holding arrangements in a lathe. The lathe shown to us had a simple three jaw chuck fitted onto its spindle. The chucks may be three jaw chuck, four jaw chuck, collet chuck, pneumatic chucks, magnetic chucks etc. Longer work pieces in a lathe, are held between centres. Centres may be a normal centre, revolving centre, tipped centre, half centre, ball centre, self driving centre or a female centre. These centres may hold the workpiece but are not able to transmit power from the spindle to the workpiece. For this purpose, Dogs are used. Mandrels play a very important role. They are basically used to keep the workpiece centred during all the operations carried on it. Suppose blanking operation has been done on a job, and it has to be taken to a milling machine for further gear cutting operation. Now as we are aware that the work is centred along the axis of the mandrel, further cutting is easily performed.

Injection Moulding

It is a manufacturing technique for making parts from thermoplastic and thermosetting plastic

in production. Injection moulding is accomplished by large machines called injection molding

machines. Molten plastic is injected at high pressure into a mould which is the inverse of the

product’s shape.

Resin enters the barrel through the hopper as shown in the figure. Colorants are added through

the hopper itself just after the addition of resin. Resin is then heated to an appropriate melting

temperature. Resin enters the mold by a reciprocating screw or a ram injector. Its reciprocating

screw mechanism is shown below.

The reciprocating screw offers the advantage of being able to inject a smaller percentage of the

total shot (amount of melted resin in the barrel). The ram injector must typically inject at least

20% of the total shot while a screw injector can inject as little as 5% of the total shot.

Essentially, the screw injector is better suited for producing smaller parts.

The mold is the part of the machine that receives the plastic and shapes it appropriately. The

mold is cooled constantly to a temperature that allows the resin to solidify and be cool to the

touch. The mold plates are held together by hydraulic or mechanical force.