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CHAPTER- 1
INTRODUCTION
1.1 Introduction of VECV
VE Commercial Vehicles Limited is a joint venture between the Volvo Group (Volvo) and
Eicher Motors Limited (EML). It is a partnership that brings together Global leadership in
technology, quality, safety and environmental care, along with the deep knowledge and
understanding of the Indian Commercial Vehicle (CV) market. VE Commercial Vehicles
Limited. (VECV) owes its inception to the compelling intent of driving modernization in
commercial transportation, in India and other developing markets.
1.1.1 Key points
 VE Commercial Vehicles Limited (VECV) is a joint venture between the Volvo
Group and Eicher Motors Limited, and is headquartered at New Delhi. This joint
venture came into effect in July 2008.
 ETB, completed 31 years of operations in India in the month of June 2017. The first
Eicher truck was rolled out from its manufacturing plant in Pithampur, Madhya
Pradesh in 1986 and over the past 29 years, the products have got endorsement from
happy customers of over 6,14,000 vehicles.
 Eicher 12-69 seater buses have a growing presence in the LMD school bus ,staff and
route-permit segments. ETB has also made strong inroads into heavy-duty trucks
segment of 16T-49T with their "VE" series of Fuel Efficient heavy-duty trucks, and
the next generation Eicher Pro Series of heavy Duty Trucks.
 The state-of-the-art plant in Pithampur has top line manufacturing processes which
includes cab weld shop with robotic welding, CED paint shop, integrated testing
facilities, 100% hot test facility for engines and a lean and scalable manufacturing set
up. It offers superior paint finish and deliver quality much superior to what we see in
contemporary trucks in India. The top coat paint finish is superior in terms of gloss,
distinctness of image and corrosion resistance.

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 Volvo Trucks in India is the first truck manufacturer to introduce the European
design, high performance trucks with the latest technologies. To provide an all-round
solution Volvo Trucks in India pioneered the Driver Training concept in commercial
vehicles segment. Today, there are over 30,000 drivers trained by Volvo, operating
Volvo vehicles across the country for private as well as public transports. When it
comes to maintaining a Volvo Truck as a true Volvo, Genuine Volvo Parts helps the
truck retains its original properties throughout its lifetime. Complementing the trucks,
Volvo Trucks offers a wide range of Service Agreements to help customers plan the
maintenance.
 Eicher Engineering Components (EEC) is the automotive component division of
VECV. Established in 1992, EEC has grown to become one of the largest and most
well reputed gear manufacturers in India. Not only does EEC meet all the automotive
component requirements of Eicher Trucks and Buses, it also manufactures differential
gears, transmission gears and shafts for a large domestic and global clientele, both in
the OEM and spare-parts segments. Besides, EEC also supplies gear boxes to
industrial, agricultural and other segments in the United States and Canada. EEC has
four manufacturing plants, one at Thane (Maharashtra) and two at Dewas (Madhya
Pradesh) manufacturing the complete range of gears, and one at Pithampur (Madhya
Pradesh) manufacturing gear boxes. It is continuously developing new products and
upgrading its technology, while increasing operational efficiency, to make sure that it
gets the best products to the market at the most competitive rates.
 The Plant in Dewas, Madhya Pradesh houses technologically advanced machines and
equipment which includes a battery of Mitsubishi CNC Hobbing machines, fellow
shaping machines, Reishauer Gear Grinder RZ400, Shaving Cutter Re-sharpening
machine from Gleason Hurth, state-of-the-art Continuous Gas Carburising Furnace
(from Aichelin) - fully PLC controlled with robotics for Press Quenching and PLC
Controlled Sealed Quench Furnaces (with hot oil quenching for reduced distortions).
Ground breaking ceremony of the proposed second unit at Dewas took place in
January 2012.
 VECV has an employee base of 11000+ employees.

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1.1.2 VECV overview
 Eicher Trucks and Buses
Eicher Trucks and Buses (ETB) are present in the L/MD segment with a strong presence in the
5T-12T truck segment. Eicher new Pro series trucks and buses promise to deliver best-in-class
fuel efficiency, higher loading capacity and superior uptime.
Figure 1.1 Eicher trucks and busses
 Volvo Trucks India
Volvo Trucks in India is synonymous with the mining and the construction industries. Volvo
Trucks in India is the first truck manufacturer to introduce the European design, high performance
trucks with the latest technologies.
Figure 1.2 Volvo Trucks India

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 Eicher Engineering Components
EEC is the automotive component division of VECV. EEC came into existence in 1992 and has
become an established player in its segment of manufacturing Power-train components
(Differential Gears, Transmission Gears & Shafts) and Gear Boxes.
Figure 1.3 Eicher engineering components
 VE Powertrain
Commemorating successful completion of five years of partnership between Volvo Group and
Eicher Motors in, VE Commercial Vehicles Limited announced start of commercial production at
the technologically most advanced engine manufacturing plant in India in July 2013.
Figure 1.4 VE powertrain

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1.1.3 Market share
Figure 1.5 Market share
Figure 1.6 VECV sales trend

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1.2 Business areas of VECV
Eicher Motors Limited comprises of the automotive businesses of the Eicher Group. The
business activities of the company are carried out by its constituent Business Units, each
covering a product category as described below.
Table 1.1 Bussiness Area of VECV
Business Area Products
VE Commercial Vehicles Ltd - Eicher Trucks & Buses, Volvo Trucks,
Gears & Shafts
Motorcycles - Royal Enfield
1.3 Vision and Mission
1.3.1 Vision
To be recognised as the industry leader driving modernization in commercial transportation
in India and the developing world.
1.3.2 Mission
VECV aims to continuously improve transportation efficiency in India and developing
markets, thereby reducing logistics costs for goods and people – leading to higher enablement
of specialisation in manufacturing, agriculture and services, thereby increasing the nation's
economic activity and productivity.
 We choose to do this in a sustainable manner by having the safest, most durable and
efficient products in the market.

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 We care for our customers holistically by offering not just trucks and buses, but also
the best service and soft products to enable him to be most profitable.
 We work with the driver community to enhance their productivity and overall
working environment.
 We ensure a level of quality and innovation that will continue to set standards in the
commercial transportation industry.

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CHAPTER-2
EICHER ENGINEERING COMPONENTS
2.1 About EEC
EEC is the automotive component division of VECV. EEC came into existence in 1992 and
has become an established player in its segment of manufacturing Power-train components
(Differential Gears, Transmission Gears & Shafts) and Gear Boxes.
Established in - Unit 1 - 2006 (taken over by Eicher); Unit 2 - 2012 (Greenfield facility)
Production Capacity - Gears & Shafts - 250,000 nos. p.m., Crown Wheels & Pinions - 16,000
sets p.m., Straight Bevels - 25,000 nos. p.m.
2.1.1 In House Product
Crown wheel Pinion, Speed Gears, Straight Bevel, and Transmission Shaft.
2.1.2 Outsourced Product
Aluminum Castings, Fabricated & Painted Parts, Fabricated Axle Housing, Forged Parts,
Forged Toughened & Machined Parts, Investment Castings, Precision Complex Shaped
Machined Castings, Precision Machined Castings, Precision Turned Forged Components,
Pressed & Welded Differential Cover, Proprietary Parts, Shift Cover Assembly, Slip
Differentials.
2.1.3 Gear Box Assembly
Axle Tube Assembly, Double Gearbox, Drop Axle, Rear Axle Assembly, Right Angle Bevel
Gearbox (Ratio - 1.79:1), Bevel Gear Drive Gearbox, Coniflex Bevel Shifter Gearbox, Gear
Assembly, Parallel Axis Gearbox, Tractor Transmission, Triple Gearbox, Worm Gearbox
(Ratio - 05:1-20:1), Worm Gearbox (Ratio - 10:1), Worm Gearbox (Ratio - 25:1-50:1)

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2.2 Gear manufacturing
Gear manufacturing refers to the making of gears. Gears can be manufactured by a variety of
processes, including casting, forging, extrusion, powder metallurgy, and blanking. As a
general rule, however, machining is applied to achieve the final dimensions, shape and
surface finish in the gear. The initial operations that produce a semi finishing part ready for
gear machining as referred to as blanking operations, the starting product in gear machining
is called a gear blank.
2.2.1 Selection of materials
The gear material should have the following properties:
 High tensile strength to prevent failure against static loads
 High endurance strength to withstand dynamic loads
 Low coefficient of friction
 Good manufacturability
2.3 Gear manufacturing processes
2.3.1 Gear forming
In gear form cutting, the cutting edge of the cutting tool has a shape identical with the shape
of the space between the gear teeth. Two machining operations, milling and broaching can be
employed to form cut gear teeth.
2.3.2 Form milling
In form milling, the cutter called a form cutter travels axially along the length of the gear
tooth at the appropriate depth to produce the gear tooth. After each tooth is cut, the cutter is
withdrawn, the gear blank is rotated, and the cutter proceeds to cut another tooth. The process
continues until all teeth are cut.
2.3.3 Broaching
Broaching can also be used to produce gear teeth and is particularly applicable to internal
teeth. The process is rapid and produces fine surface finish with high dimensional accuracy.

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However, because broaches are expensive and a separate broach is required for each size of
gear, this method is suitable mainly for high-quality production.
2.4 Gear generation
In gear generation, the tooth flanks are obtained as an outline of the subsequent positions of
the cutter, which resembles in shape the mating gear in the gear pair. There are two
machining processes employed shaping and milling. There are several modifications of these
processes for different cutting tool used.
2.4.1 Gear hobbing
Gear hobbing is a machining process in which gear teeth are progressively generated by a
series of cuts with a helical cutting tool. All motions in hobbing are rotary, and the hob and
gear blank rotate continuously as in two gears meshing until all teeth are cut.
2.5 Casting
Casting is a manufacturing process in which a liquid material is usually poured into a mold,
which contains a hollow cavity of the desired shape, and then allowed to solidify. The
solidified part is also known as a casting, which is ejected or broken out of the mold to
complete the process. Casting materials are usually metals or various cold setting materials
that cure after mixing two or more components together; examples
are epoxy, concrete, plaster and clay. Casting is most often used for making complex shapes
that would be otherwise difficult or uneconomical to make by other methods.
Figure 2.1 Casting process

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2.5.1 Types of casting
2.5.1.1 Metal casting
In metalworking, metal is heated until it becomes liquid and is then poured into a mold. The
mold is a hollow cavity that includes the desired shape, but the mold also
includes runners and risers that enable the metal to fill the mold. The mold and the metal are
then cooled until the metal solidifies. The solidified part (the casting) is then recovered from
the mold. Subsequent operations remove excess material caused by the casting process (such
as the runners and risers).
2.5.1.2 Plaster, concrete, or plastic resin
Plaster and other chemical curing materials such as concrete and plastic resin may be cast
using single-use waste molds as noted above, multiple-use 'piece' molds, or molds made of
small rigid pieces or of flexible material such as latex rubber (which is in turn supported by
an exterior mold). When casting plaster or concrete, the material surface is flat and lacks
transparency. Often topical treatments are applied to the surface. For example, painting and
etching can be used in a way that gives the appearance of metal or stone. Alternatively, the
material is altered in its initial casting process and may contain coloured sand so as to give an
appearance of stone. By casting concrete, rather than plaster, it is possible to create
sculptures, fountains, or seating for outdoor use. A simulation of high-quality marble may be
made using certain chemically-set plastic resins (for example epoxy or polyester which
are thermosetting polymers) with powdered stone added for coloration, often with multiple
colors worked in. The latter is a common means of making washstands, washstand tops and
shower stalls, with the skilled working of multiple colors resulting in simulated staining
patterns as is often found in natural marble or travertine.
2.6 Fettling
Raw castings often contain irregularities caused by seams and imperfections in the molds, as
well as access ports for pouring material into the molds. The process of cutting, grinding,
shaving or sanding away these unwanted bits is called "fettling". In modern times robotic
processes have been developed to perform some of the more repetitive parts of the fettling
process, but historically fettlers carried out this arduous work manually, and often in
conditions dangerous to their health. Fettling can add significantly to the cost of the resulting

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product, and designers of molds seek to minimize it through the shape of the mold, the
material being cast, and sometimes by including decorative elements.
2.7 Casting process simulation
Casting process simulation uses numerical methods to calculate cast component quality
considering mold filling, solidification and cooling, and provides a quantitative prediction of
casting mechanical properties, thermal stresses and distortion. Simulation accurately
describes a cast component‟s quality up-front before production starts. The casting rigging
can be designed with respect to the required component properties. This has benefits beyond
a reduction in pre-production sampling, as the precise layout of the complete casting system
also leads to energy, material, and tooling savings.
The software supports the user in component design, the determination of melting practice
and casting methoding through to pattern and mold making, heat treatment, and finishing.
This saves costs along the entire casting manufacturing route. Casting process simulation was
initially developed at universities starting from the early '70s, mainly in Europe and in the
U.S., and is regarded as the most important innovation in casting technology over the last 50
years. Since the late '80s, commercial programs (such as AutoCAST and are available which
make it possible for foundries to gain new insight into what is happening inside the mold or
die during the casting process.
2.8 Forging
Forging is a manufacturing process involving the shaping of metal using
localized compressive forces. The blows are delivered with a hammer (often a power
hammer) or a die. Forging is often classified according to the temperature at which it is
performed: cold forging (a type of cold working), warm forging, or hot forging (a type of hot
working). For the latter two, the metal is heated, usually in a forge. Forged parts can range in
weight from less than a kilogram to hundreds of metric tons.[1][2]
Forging has been done
by smiths for millennia; the traditional products were kitchenware, hardware, hand
tools, edged weapons, cymbals, and jewellery. Since the Industrial Revolution, forged parts
are widely used in mechanisms and machines wherever a component requires high strength;
such forgings usually require further processing (such as machining) to achieve a finished
part. Today, forging is a major worldwide industry.

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Figure 2.2 Forged part
2.8.1 Types of Forging
2.8.1.1 Temperature
All of the following forging processes can be performed at various temperatures; however,
they are generally classified by whether the metal temperature is above or below the
recrystallization temperature. If the temperature is above the material's recrystallization
temperature it is deemed hot forging; if the temperature is below the material's
recrystallization temperature but above 30% of the recrystallization temperature (on an
absolute scale) it is deemed warm forging; if below 30% of the recrystallization temperature
(usually room temperature) then it is deemed cold forging. The main advantage of hot forging
is that it can be done more quickly and precisely, and as the metal is deformed work
hardening effects are negated by the recrystallization process. Cold forging typically results
in work hardening of the piece.
2.8.1.2 Drop forging
Drop forging is a forging process where a hammer is raised and then "dropped" onto the
workpiece to deform it according to the shape of the die. There are two types of drop forging:

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open-die drop forging and closed-die drop forging. As the names imply, the difference is in
the shape of the die, with the former not fully enclosing the workpiece, while the latter does.
Figure 2.3 Drop forging
2.8.1.3 Press forging
Press forging works by slowly applying a continuous pressure or force, which differs from
the near-instantaneous impact of drop-hammer forging. The amount of time the dies are in
contact with the workpiece is measured in seconds (as compared to the milliseconds of drop-
hammer forges). The press forging operation can be done either cold or hot.
The main advantage of press forging, as compared to drop-hammer forging, is its ability to
deform the complete workpiece. Drop-hammer forging usually only deforms the surfaces of
the work piece in contact with the hammer and anvil; the interior of the workpiece will stay
relatively undeformed. Another advantage to the process includes the knowledge of the new
part's strain rate. By controlling the compression rate of the press forging operation, the
internal strain can be controlled.
There are a few disadvantages to this process, most stemming from the workpiece being in
contact with the dies for such an extended period of time. The operation is a time-consuming
process due to the amount and length of steps. The workpiece will cool faster because the
dies are in contact with workpiece; the dies facilitate drastically more heat transfer than the

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surrounding atmosphere. As the workpiece cools it becomes stronger and less ductile, which
may induce cracking if deformation continues. Therefore, heated dies are usually used to
reduce heat loss, promote surface flow, and enable the production of finer details and closer
tolerances. The workpiece may also need to be reheated.
When done in high productivity, press forging is more economical than hammer forging. The
operation also creates closer tolerances. In hammer forging a lot of the work is absorbed by
the machinery; when in press forging, the greater percentage of work is used in the work
piece. Another advantage is that the operation can be used to create any size part because
there is no limit to the size of the press forging machine. New press forging techniques have
been able to create a higher degree of mechanical and orientation integrity.
2.8.1.4 Automatic hot forging
The automatic hot forging process involves feeding mill-length steel bars (typically 7 m
(23 ft) long) into one end of the machine at room temperature and hot forged products emerge
from the other end. This all occurs rapidly; small parts can be made at a rate of 180 parts per
minute (ppm) and larger can be
up to 18 cm (7.1 in) in diameter. The main advantages to this process are its high output rate
and ability to accept low-cost materials. Little labour is required to operate the machinery.
There is no flash produced so material savings are between 20 and 30% over conventional
forging. The final product is a consistent 1,050 °C (1,920 °F) so air cooling will result in a
part that is still easily machinable (the advantage being the lack of annealing required after
forging). Tolerances are usually ±0.3 mm (0.012 in), surfaces are clean, and draft angles are
0.5 to 1°. Tool life is nearly double that of conventional forging because contact times are on
the order of 0.06-second. The downside is that this process is only feasible on smaller
symmetric parts and cost; the initial investment can be over $10 million, so large quantities
are required to justify this process.
The process starts by heating the bar to 1,200 to 1,300 °C (2,190 to 2,370 °F) in less than 60
seconds using high-power induction coils. It is then descaled with rollers, sheared into blanks,
and transferred through several successive forming stages, during which it is upset,
preformed, final forged, and pierced (if necessary).

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2.9 Extrusion
Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is
pushed through a die of the desired cross-section. The two main advantages of this process
over other manufacturing processes are its ability to create very complex cross-sections, and
to work materials that are brittle, because the material only
encounters compressive and shear stresses. It also forms parts with an excellent surface
finish.Extrusion may be continuous (theoretically producing indefinitely long material) or
semi-continuous (producing many pieces). The extrusion process can be done with the
material hot or cold. Commonly extruded materials
include metals, polymers, ceramics, concrete, modelling clay, and foodstuffs. The products of
extrusion are generally called "extrudates".
Figure 2.4 Extrusion process
2.9.1 Types of Extrusion
2.9.1.1 Hot extrusion
Hot extrusion is a hot working process, which means it is done above the
material's recrystallization temperature to keep the material from work hardening and to
make it easier to push the material through the die. Most hot extrusions are done on
horizontal hydraulic presses that range from 230 to 11,000 metric tons (250 to 12,130 short
tons). Pressures range from 30 to 700 MPa (4,400 to 101,500 psi), therefore lubrication is
required, which can be oil or graphite for lower temperature extrusions, or glass powder for
higher temperature extrusions. The biggest disadvantage of this process is its cost for
machinery and its up keep.

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Table 2.1 Hot extrusion temperature for various metals
Material Temperature [°C (°F)]
Magnesium 350–450 (650–850)
Aluminium 350–500 (650–900)
Copper 600–1100 (1200–2000)
Steel 1200–1300 (2200–2400)
Titanium 700–1200 (1300–2100)
Nickel 1000–1200 (1900–2200)
Refractory alloys up to 2000 (4000)
2.9.1.2 Cold extrusion
Cold extrusion is done at room temperature or near room temperature. The advantages of this
over hot extrusion are the lack of oxidation, higher strength due to cold working, closer
tolerances, better surface finish, and fast extrusion speeds if the material is subject to hot
shortness.
Examples of products produced by this process are: collapsible tubes, fire
extinguisher cases, shock absorber cylinders and gear blanks.

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2.9.1.3 Warm extrusion
In March 1956, a US Patent was filed for "process for warm extrusion of metal." Patent
US3156043 A outlines that a number of important advantages can be achieved with warm
extrusion of both ferrous and non-ferrous metals and alloys if a billet to be extruded is
changed in its physical properties in response to physical forces by being heated to a
temperature below the critical melting point.[3]
Warm extrusion is done above room
temperature, but below the recrystallization temperature of the material the temperatures
ranges from 800 to 1800 °F (424 to 975 °C). It is usually used to achieve the proper balance
of required forces, ductility and final extrusion properties.
2.9.1.4 Friction extrusion
Friction extrusion was invented at The Welding Institute in the UK and patented in 1991. It
was originally intended primarily as a method for production of homogenous microstructures
and particle distributions in metal matrix composite materials. Friction extrusion differs from
conventional extrusion in that the charge (billet or other precursor) rotates relative to the
extrusion die. An extrusion force is applied so as to push the charge against the die. In
practice either the die or the charge may rotate or they may be counter-rotating. The relative
rotary motion between the charge and the die has several significant effects on the process.
First, the relative motion in the plane of rotation leads to large shear stresses, hence, plastic
deformation in the layer of charge in contact with and near the die. This plastic deformation
is dissipated by recovery and recrystallization processes leading to substantial heating of the
deforming charge. Because of the deformation heating, friction extrusion does not generally
require preheating of the charge by auxiliary means potentially resulting in a more energy
efficient process. Second, the substantial level of plastic deformation in the region of relative
rotary motion can promote solid state welding of powders or other finely divided precursors,
such as flakes and chips, effectively consolidating the charge (friction consolidation) prior to
extrusion.
2.9.1.5 Micro extrusion
Micro extrusion is a micro forming extrusion process performed at the sub millimetre range.
Like extrusion, metal is pushed through a die orifice, but the resulting product's cross section
can fit through a 1mm square. Several micro extrusion processes have been developed since
micro forming was envisioned in 1990. Forward (ram and billet move in the same direction)

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and backward (ram and billet move in the opposite direction) micro extrusion were first
introduced, with forward rod-backward cup and double cup extrusion methods developing
later. Regardless of method, one of the greatest challenges of creating a successful micro
extrusion machine is the manufacture of the die and ram. "The small size of the die and ram,
along with the stringent accuracy requirement, needs suitable manufacturing
processes."]
Additionally, as Fu and Chan pointed out in a 2013 state-of-the-art technology
review, several issues must still be resolved before micro extrusion and other micro forming
technologies can be implemented more widely, including deformation load and defects,
forming system stability, mechanical properties, and other size-related effects on
the crystallite (grain) structure and boundaries.

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CHAPTER–3
NEW PRODUCT DEVELOPMENT
3.1 Introduction
New product development (NPD) is the process of bringing a new product to the
marketplace. The product can be tangible (something physical which one can touch) or
intangible (like a service, experience, or belief), though sometimes services and other
processes are distinguished from "products." NPD requires an understanding of customer
needs and wants, the competitive environment, and the nature of the market.[2]
Cost, time and
quality are the main variables that drive customer needs. Aiming at these three
variables, companies develop continuous practices and strategies to better satisfy customer
requirements and to increase their own market share by a regular development of new
products.
3.2 Process
Table 3.1 Process Chart
Marketing product duration
Feasibility
Tooling cost
Cutting tools & Fixture
Gauge Design
Control plan
Sample Development
Production part approval process
PRODUCTION

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3.3 Marketing product duration
It is the time duration in which the product has to be developed.
3.4 Feasibility
The term “feasibility” is often used in context of product development processes. Feasibility
studies focus on five subjects: technical, economic, legal, operational and scheduling
feasibility studies. The best known field is the economic one. While in economy science there
is a standard-proceeding of “feasibility”.
In the manufacturing of gear, the feasibility of a product depends upon certain points:
 The availability of the machine for production
 The availability of time
 The cost of manufacturing
 The return on investment
3.5 Tooling cost
When you request a quote of a manufacturer they will always give you a tooling cost. The
tooling cost is a cost that is charged for the engineering / fabrication of the tool that will be
used to make your product. Typically these tools are called dies.
Dies are produced based on your 2D or 3D files of your designs and usually made from
number different types of metals.
Once made the dies are made they are inserted into large machines which will then enable
you to start production of your parts. Dies will compress, stretch, form, mold and bend
material into the desired shape. Without a die you cannot make your part.

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3.6 Gauge Design
Gauges are inspection tool of rigid design, without a scale, which serves to check the
dimensions of manufacturing parts. Gauges do not indicate the actual value of the inspected
part of the component. They are used to determine whether the part is made within the
specified limit.
3.6.1 Types of Gauges
3.6.1.1 Plug Gauge
Plug gauges are simple mechanical inspection instruments used to verify compliance of
threaded or plain holes to upper and lower dimensional limits. Plug gauges are designed to
“fit” or “not fit” (e.g. Go/No-Go gauge) into holes, etc. Key specifications of limit gauges
include the gauge type, gauge function and measurement range. Plug gauges are primarily
used as a quick pass/fail test to determine if a hole diameter or thread feature lies within the
specified range of acceptance.
Figure 3.1 Plug gauge

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3.6.1.2 Height Gauge
Height gauges are electro-mechanical or mechanical metrology instruments that measure the
dimension of machined parts from a datum reference--a surface plate, for example. A height
gauge generally consists of a rigid column mounted to flat base with a measuring head that
displays height from the bottom of the base on a dial, vernier, or digital display. Key
specifications include height gauge type, measurement range, and resolution. Height gauges
are used in machining operations for inspecting finished parts.
Figure 3.2
3.6.1.3 Ring Gauge
A ring gauge, or ring gage is a cylindrical ring of a thermally stable material, often steel,
whose inside diameter is finished to gauge tolerance and is used for checking the external
diameter of a cylindrical object.
Ring gauges are used for comparative gauging as well as for checking, calibrating, or setting
of gauges or other standards. Individual ring gauges or ring gauge sets are made to variety of
tolerance grades in metric and English dimensions for master, setting, or working
applications.
There are three main types of ring gauges: go, no go, and master or setting ring gauges.
Go ring gauges provide a precision tool for production comparative gauging based on a fixed
limit. Go gauges consist of a fixed limit gauge with a gauging limit based on the plus or
minus tolerances of the inspected part. A go ring gauge's dimensions are based on the

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maximum OD tolerance of the round bar or part being gauged. A go plug gauge's dimensions
are based on the minimum ID tolerance of the hole or part being gauged. The go plug (ID)
gauge should be specified to a plus „gauge makers' tolerance from the minimum part
tolerance. The go ring (OD) gauge should be specified to a minus „gauge makers' tolerance
from the maximum part tolerance.
No-go or not-go gauges provide a precision tool for production comparative gauging based
on a fixed limit. No-go gauges consist of a fixed limit gauge with a gauging limit based on
the minimum or maximum tolerances of the inspected part. A no-go ring gauge's dimensions
are based on the minimum OD tolerance of the round bar or part being gauged. The no go
ring (OD) gauge should be specified to a plus „gauge makers' tolerance from the minimum
part tolerance.
Master and setting ring gauges includes gauge blocks, master or setting discs, and setting
rings are types of master gauges used to calibrate or set micro meters, optical comparators, or
other gauging systems. Working gauges are used in the shop for dimensional inspection and
periodically checked against a master gauge.
3.6.1.4 Snap gage
Snap gauges are simple mechanical inspection instruments used to verify that the outside
dimensions of parts are within their specified tolerances. Key specifications include features,
range, and accuracy. Snap gauges can be either fixed or adjustable devices. Fixed snap
gauges are manufactured to set measurements whereas adjustable snap gauges can be set to
measure over ranges of measurements.
Figure 3.3 Ring gauge

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3.6.1.5 Depth Gauge
Depth gauges are electro-mechanical or mechanical metrology instruments that measure the
inside lengths of holes and other machined cavities. A depth gauge generally consists of an
anvil, an indicating dial, and a probe assembly. Direct reading rules and digital readouts are
available as well. Key specifications include depth gauge type, measurement range, and
graduation, dial reading, along with a host of possible features. Depth gauges vary in their
readouts from simple direct reading tic marks to digitally displayed numerals, with
corresponding accuracy. Other depth gauges are used for measuring the tread depths of tires.
3.6.1.6 Functional Fixture Gauge
A Functional Fixture Gauge provides the means to locate the part based on part or machine
requirements. Our designs utilize geometrics, machining process information and part print
tolerance (GD&T) practices. Gauging units are applied to specific features of the part,
providing results based on criteria of a good or bad part condition according to customer
specifications.
Figure 3.4 Functional Gauge

26
3.7 Control Plan
The Control Plan is a document that describes the actions (measurements, inspections, quality
checks or monitoring of process parameters) required at each phase of a process to assure the
process outputs will conform to pre-determined requirements. In simpler terms, the Control
Plan provides the operator or inspector with the information required to properly control the
process and produce quality parts or assemblies. It should also include instructions regarding
actions taken if a non-conformance is detected. The Control Plan does not replace detailed
operator instructions. In some cases the Control Plan is used in conjunction with an
inspection sheet or checklist. The Control Plan helps assure quality is maintained in a process
in the event of employee turnover by establishing a standard for quality inspection and
process monitoring. Control Plans are living documents that should be periodically updated
as the measurement methods and controls are improved throughout the life cycle of the
product.
Figure 3.5 Control Plan
3.7.1 Why Control Plan
Developing and implementing Control Plan Methodology has several benefits. The use of
Control Plans helps reduce or eliminate waste in a process. Businesses today must reduce
waste everywhere possible. The Control Plan improves product quality by identifying the
sources of variation in a process and establishing controls to monitor them. Control Plans
focus on the product characteristics most important to the customer and the business. By
focusing on what is critical to quality during the process, you can reduce scrap, eliminate

27
costly reworks and prevent defective product from reaching the customer. When scrap and
reworks are reduced, throughput of the process is inherently improved. Manufacturing
efficiency is improved and your company‟s bottom line is impacted in a positive manner.
3.7.2 How to Develop a Control Plan
The Control Plan should be developed by a Cross Functional Team (CFT) that has an
understanding of the process being controlled or improved. By utilizing a CFT, you are
likely to identify more opportunities for improvement of the process. The Control Plan is
more than just a form to fill out. It is a plan developed by the team to control the process and
ensure the process produces quality parts that meet the customer requirements. The
information contained in the control plan can originate from several sources, including but
not limited to the following:
 Process Flow Diagram
 Design Failure Mode and Effects Analysis (DFMEA)
 Process Failure Mode and Effects Analysis (PFMEA)
 Special Characteristics Matrix
 Lessons Learned from similar parts
 Design Reviews
 Team knowledge about the process
 Field or warranty issues
Throughout the life cycle of a product, the information contained in the list above frequently
changes or the content grows. Therefore the Control Plan must be a living document,
continuously updated as new information is added. The Control Plan therefore is an integral
part of an effective product quality system.
3.7.3 Levels of Control Plan
Prior to completing the Control Plan development, the team must determine the proper level
appropriate for the process being controlled. There are three designations for a Control Plan
level based upon what point the product is at in the New Product Introduction (NPI) process.
They are as follows:

28
1. Prototype – This level Control Plan should include descriptions of the dimensions to be
measured and the material and performance tests to be completed during the prototype
build
2. Pre-Launch – This level of Control Plan should contain descriptions of the dimensions to
be measured and the material and performance tests to be completed after prototype but
prior to product launch and regular production
3. Production – This level of Control Plan should contain a comprehensive listing of the
product and process special characteristics, the process controls, measurement methods
and tests that will be performed during regular production
3.8 Production Part Approval Process
PPAP defines the approval process for new or revised parts, or parts produced from new or
significantly revised production methods. The PPAP process consists of 18 elements that
may be required for approval of production level parts. Not all of the elements are required
for every submission. There are five generally accepted PPAP submission levels. The PPAP
manual contains detailed information, guidelines and sample documents useful for
completing the process requirements. The resulting PPAP submission provides the evidence
that the supplier has met or exceeded the customer‟s requirements and the process is capable
of consistently reproducing quality parts.
3.8.1 Why Perform PPAP
The PPAP process verifies that the supplier understands all customer engineering design
specifications and requirements and that the process is capable of consistently producing
product meeting those requirements during an actual production run at the quoted production
rate. PPAP and other quality tools continue to be implemented into more industries; therefore
it is important to gain an understanding of the PPAP requirements to remain competitive as a
parts supplier.
3.8.2 When to Perform PPAP
A PPAP is required for any new part submission as well as for approval of any change to an
existing part or process. The customer may request a PPAP at any time during the product
life. This demands that the supplier must maintain a quality system that develops and
documents all of the requirements of a PPAP submission at any time.

29
3.8.3 How to Perform PPAP
The process of completing a PPAP submission is fairly complex. This detailed process is a
collection of key elements that must be completed to verify that the production process will
produce a quality product. Not all of the elements are always required for a PPAP
submission. The particular requirements of the PPAP are usually negotiated during the
quoting process.
3.8.4 PPAP Levels of Submission
The PPAP submission requirements are normally divided into five classifications or levels,
as follows:
 Level 1 – Part Submission Warrant (PSW) only submitted to the customer
 Level 2 – PSW with product samples and limited supporting data
 Level 3 – PSW with product samples and complete supporting data
 Level 4 – PSW and other requirements as defined by the customer
 Level 5 – PSW with product samples and complete supporting data available for review
at the supplier‟s manufacturing location.
3.8.5 Elements of PPAP
 Design Documentation
 Engineering Change Documentation
 Design Failure Mode and Effects Analysis
 Process Flow Diagram
 Process Failure Mode and Effects Analysis
 Measurement System Analysis Studies
 Dimensional Results
 Records of Material / Performance Tests
 Qualified Laboratory Documentation
 Appearance Approval Report
 Customer Specific Requirements

30
3.9 Production
3.9.1 Hobbing
Hobbing is a machining process for gear cutting, cutting splines, and cutting sprockets on
a hobbing machine, which is a special type of milling machine. The teeth or splines are
progressively cut into the workpiece by a series of cuts made by a cutting tool called a hob.
Compared to other gear forming processes it is relatively inexpensive but still quite accurate,
thus it is used for a broad range of parts and quantities.
It is the most widely used gear cutting process for creating spur and helical gears and more
gears are cut by hobbing than any other process as it is relatively quick and inexpensive.[3]
A type of skiving that is analogous to the hobbing of external gears can be applied to the
cutting of internal gears, which are skived with a rotary cutter (rather
than shaped or broached).
3.9.1.1 Process
Hobbing uses a hobbing machine with two skew spindles, one mounted with a blank
workpiece and the other with the hob. The angle between the hob's spindle (axis) and the
workpiece spindle varies, depending on the type of product being produced. For example, if a
spur gear is being produced, then the hob is angled equal to the helix angle of the hob; if a
helical gear is being produced then the angle must be increased by the same amount as the
helix angle of the helical gear. The two shafts are rotated at a proportional ratio, which
determines the number of teeth on the blank; for example, for a single-threaded hob if the
gear ratio is 40:1 the hob rotates 40 times to each turn of the blank, which produces 40 teeth
in the blank. If the hob has multiple threads the speed ratio must be multiplied by the number
of threads on the hob. The hob is then fed up into the workpiece until the correct tooth depth
is obtained. Finally the hob is fed through the workpiece parallel to the blank's axis of
rotation. Often multiple blanks are stacked and then cut in one operation.
For very large gears the blank can be gashed to the rough shape first to make hobbing easier.
3.9.1.2 Equipment
Hobbing machines, also known as hobbers, are fully automated machines that come in many
sizes, because they need to be able to produce anything from tiny instrument gears up to 10 ft

31
(3.0 m) diameter marine gears. Each gear hobbing machine typically consists of
a chuck and tailstock, to hold the workpiece or a spindle, a spindle on which the hob is
mounted, and a drive motor.
For a tooth profile which is a theoretical involute, the fundamental rack is straight-sided, with
sides inclined at the pressure angle of the tooth form, with flat top and bottom. The
necessary addendum correction to allow the use of small-numbered pinions can either be
obtained by suitable modification of this rack to a cycloidal form at the tips, or by hobbing at
other than the theoretical pitch circle diameter. Since the gear ratio between hob and blank is
fixed, the resulting gear will have the correct pitch on the pitch circle, but the tooth thickness
will not be equal to the space width.
Hobbing machines are characterised by the largest module or pitch diameter it can generate.
For example, a 10 in (250 mm) capacity machine can generate gears with a 10 in pitch
diameter and usually a maximum of a 10 in face width. Most hobbing machines are vertical
hobbers, which mean the blank is mounted vertically. Horizontal hobbing machines are
usually used for cutting longer workpiece; i.e. cutting splines on the end of a shaft.
Figure 3.6 CNC Hobbing machine

32
3.9.1.3 Hob
The hob is a cutting tool used to cut the teeth into the workpiece. It is cylindrical in shape
with helical cutting teeth. These teeth have grooves that run the length of the hob, which aid
in cutting and chip removal. There are also special hobs designed for special gears such as the
spline and sprocket gears.
The cross-sectional shape of the hob teeth are almost the same shape as teeth of a rack
gear that would be used with the finished product. There are slight changes to the shape for
generating purposes, such as extending the hob's tooth length to create a clearance in the
gear's roots. Each hob tooth is relieved on the back side to reduce friction.
Most hobs are single-thread hobs, but double-, and triple-thread hobs increase production
rates. The downside is that they are not as accurate as single-thread hobs. Depending on type
of gear teeth to be cut, there are custom made hobs and general purpose hobs. Custom made
hobs are different from other hobs as they are suited to make gears with modified tooth
profile. The tooth profile is modified to add strength and reduce size and gear noise.
Figure 3.7 Hob Cutter

33
This list outlines types of hobs:
 Roller chain sprocket hobs
 Worm wheel hobs
 Spline hobs
 Chamfer hobs
 Spur and helical gear hobs
 Straight side spline hobs
 Involute spline hobs
 Serration hobs
 Semi topping gear hobs
Figure 3.8 Hob Nomenclature
3.9.1.4 Uses
Hobbing is used to make the following types of finished gears:
 Cycloid gears
 Helical gears
 Involute gears
 Splines
 Sprockets
 Spur gears
 Worm gears

34
3.9.2 Gear Shaping
Gear shaping is a machining process for creating teeth on a gear using a cutter. Gear shaping
is a convenient and versatile method of gear cutting. It involves continuous, same-plane
rotational cutting of gear.
The types of cutters used for gear shaping can be grouped into four categories: disk, hub,
shank, and helical cutters. The cutters are essentially gears that are used to form the teeth.
This method of gear cutting is based on the principle that any two gears will mesh if they are
of the same pitch, proper helix angle, and proper tooth depth and thickness.
3.9.2.1 Process characteristics
By using a gear-shaped corresponding cutter that is rotated (in relation to a blank gear)
produces the gear teeth. The cutters that are rotated are timed with the workpiece. This
process produces internal gears, external gears, and integral gear-pinion arrangements.
3.9.2.2 Setup and equipment
The machine used for gear shaping generally consists of a base, column spindle, and an arbor.
The gear cutter is mounted on the spindle, and the gear blank is mounted on the arbor. The
cutter reciprocates up and down while the workpiece is gradually fed into the cutter. At the
end of each cutting rotation, the spindle is retracted slightly to discourage any more cutting
into the new cut teeth of the gear.
Figure 3.9 Shaping Machine

35
3.9.3 Gear Shaving
Gear shaving is a finishing operation that removes small amounts of metal from the flanks of
gear teeth. Gear shaving may correct small errors in tooth spacing, helix angle, tooth profile
and concentricity. Shaving improves the finish on tooth surfaces and can eliminate tooth end
load concentration, reduce gear noise and increase load carrying capacity. The shaving
process can improve the quality and precision of a hobbed gear of 3 classes.
In the automotive industry, the vast majority of gears used in gearboxes are suitable for gear
shaving. The productivity of a gear shaving machine is much higher compared to a gear
grinding machine. The gear shaving operation is composed by the simultaneous rotation of
workpiece and cutter as a pair of gears with crossed axes. The crossed
axes generate a reciprocal sliding action between the flank, gear tooth and the cutter teeth.
3.9.4 Gear Teeth Grinding
Grinding is a very accurate method and is, though relatively expensive, more widely used for
finishing teeth of different type and size of gears of hard material or hardened surfaces. The
properly formed and dressed wheel finishes the gear teeth flanks by fine machining or
abrading action of the fine abrasives. Like gear milling, gear grinding is also done on two
principles
 Forming
 Generation, which is more productive and accurate

36
CHAPTER-4
HEAT TREATMENT
4.1 Introduction
Heat treatment is a critical and complex element in the manufacturing of gears that greatly
impacts how each will perform in transmitting power or carrying motion to other components
in an assembly. Heat treatments optimize the performance and extend the life of gears in
service by altering their chemical, metallurgical, and physical properties. These properties are
determined by considering the gear‟s geometry, power transmission requirements, stresses at
different points within a gear under load, load cycling rates, material type, mating part
designs, and other operating conditions. Heat treatments improve physical properties such as
surface hardness, which imparts wear resistance to prevent tooth and bearing surfaces from
simply wearing out. Heat treatments also improve a gear‟s fatigue life by generating
subsurface compressive stresses to prevent pitting and deformation from high contact stresses
on gear teeth. These same compressive stresses prevent fatigue failures in gear roots from
cyclic tooth bending. Physical properties such as surface hardness, core hardness, case depth,
ductility, strength, wear resistance and compressive stress profiles can vary greatly
depending on the type of heat treatment applied. For any given type of heat treatment the
results can be tailored by modifying process parameters such as heating source, temperatures,
cycle times, atmospheres, quench media, and tempering cycles to meet specific application
requirements.
In all cases, gear design engineers understand that heat treatments play a complex and vital
role in both the ease of manufacturing and the performance of the gears they make. Today,
many options exist for the heat treatment of gears. Proper selection and design of the heat
treatment process can greatly affect performance, ease of manufacture, and economics of a
component. This paper will focus on a variety of different processes and highlight some
benefits and disadvantages of each.

37
4.2 Pre Hardening
Several heat treatments can be performed before or during the gear manufacturing process to
prepare the part for manufacturing. In many cases these steps are essential to the manufacture
of a quality gear.
4.2.1 Annealing
Annealing is primarily intended to soften the part and to improve its machinability. There are
several annealing processes, all of which involve heating to and holding at a suitable
temperature followed by cooling a specific rate usually through a critical range of
temperatures. Processes used for gears include: full or supercritical annealing where a gear
blank is heated 90-180°C (160-325°F) above the upper critical temperature (Ac3) of the steel
and then slow cooled in the furnace to around 315ºC (600ºF); inter critical annealing where
the gear is heated to a temperature between the upper and lower critical temperature (Ac1)
and then rapidly cooled; and subcritical annealing, where gears are heated to 10-38°C (50-
100°F) below the lower critical temperature followed by a slow cool in the furnace.
4.2.2 Normalizing
Normalizing plays a significant role in the control of dimensional variation during hardening
and case hardening. Normalizing is a process that involves heating the gear above the upper
critical temperature and then cooling at a rate equivalent to that of still air to relieve residual
stresses in the gear blank and for dimensional stability in subsequent heat treatment
processes. In a thermal sense, normalizing is simply austenitizing. In a microstructural sense,
normalizing is intended to produce a more homogenous microstructure. A normalized part is
very machinable, but harder than an annealed part.
4.2.3 Stress Relief
Stress relief, as its name implies, is intended to relieve internal stresses created in the gear as
a consequence of its manufacture. It is recommended for intricate shapes, especially if
aggressive machining methods are used or when large amounts of stock are being removed.
Stress relief involves heating to a temperature below the lower critical temperature, holding
long enough to fully soak the part then cooling slowly enough, usually in air, to minimize the
development of new residual stresses.

38
4.3 Heat treating
Heat treating is a group of industrial and metalworking processes used to alter the physical,
and sometimes chemical, properties of a material. The most common application
is metallurgical. Heat treatments are also used in the manufacture of many other materials,
such as glass. Heat treatment involves the use of heating or chilling, normally to extreme
temperatures, to achieve a desired result such as hardening or softening of a
material precipitation strengthening, tempering, normalizing and quenching. It is noteworthy
that while the term heat treatment applies only to processes where the heating and cooling are
done for the specific purpose of altering properties intentionally, heating and cooling often
occur incidentally during other manufacturing processes such as hot forming or welding.
4.3.1 Quenching
Quenching is the rapid cooling of a workpiece in water, oil or air to obtain certain material
properties. A type of heat treating, quenching prevents undesired low-temperature processes,
such as phase transformations, from occurring. It does this by reducing the window of
time during which these undesired reactions are both thermodynamically favorable, and
kinetically accessible; for instance, quenching can reduce the crystal grain size of both
metallic and plastic materials, increasing their hardness.
4.3.2 Quench hardening
Quench hardening is a mechanical process in which steel and cast iron alloys are
strengthened and hardened. These metals consist of ferrous metals and alloys. This is done by
heating the material to a certain temperature, depending on the material. This produces a
harder material by either surface hardening or through-hardening varying on the rate at which
the material is cooled. The material is then often tempered to reduce the brittleness that may
increase from the quench hardening process. Items that may be quenched include gears,
shafts, and wear blocks.
4.3.2.1 Purpose
Before hardening, cast steels and iron are of a uniform and lamellar (or
layered) pearlitic grain structure. This is a mixture of ferrite and cementite formed when steel
or cast iron are manufactured and cooled at a slow rate. Pearlite is not an ideal material for
many common applications of steel alloys as it is quite soft. By heating pearlite past its

39
eutectoid transition temperature of 727 °C and then rapidly cooling, some of the material‟s
crystal structure can be transformed into a much harder structure known as martensite. Steels
with this martensitic structure are often used in applications when the workpiece must be
highly resistant to deformation, such as the cutting edge of blades. This is very efficient.
4.3.2.2 Process
The process of twining is a progression, beginning with heating the sample. Most materials
are heated to between 815 and 900 °C (1,500 to 1,650 °F), with careful attention paid to
keeping temperatures throughout the workpiece uniform. Minimizing uneven heating and
overheating is key to imparting desired material properties.
The second step in the quenching process is soaking. Work pieces can be soaked in air (air
furnace), a liquid bath, or a vacuum. The recommended time allocation in salt or lead baths is
up to 6 minutes. Soaking times can range a little higher within a vacuum. As in the heating
step, it is important that the temperature throughout the sample remains as uniform as
possible during soaking.
Once the workpiece has finished soaking, it moves on to the cooling step. During this step,
the part is submerged into some kind of quenching fluid; different quenching fluids can have
a significant effect on the final characteristics of a quenched part. Water is one of the most
efficient quenching media where maximum hardness is desired, but there is a small chance
that it may cause distortion and tiny cracking. When hardness can be sacrificed, mineral oils
are often used. These oil based fluids often oxidize and form a sludge during quenching,
which consequently lowers the efficiency of the process. The quenching velocity (cooling
rate) of oil is much less than water. Intermediate rates between water and oil can be obtained
with a purpose formulated quenching, a substance with an inverse solubility which therefore
deposits on the object to slow the rate of cooling.
Quenching can also be accomplished using inert gases, such as nitrogen and noble gasses.
Nitrogen is commonly used at greater than atmospheric pressure ranging up to 20 bar
absolute. Helium is also used because its thermal capacity is greater than nitrogen.
Alternatively argon can be used; however, its density requires significantly more energy to
move, and its thermal capacity is less than the alternatives. To minimize distortion in the
workpiece, long cylindrical workpieces are quenched vertically; flat work pieces are

40
quenched on edge; and thick sections should enter the bath first. To prevent steam bubbles
the bath is agitated.
Often, after quenching, an iron or steel alloy will be excessively hard and brittle due to an
overabundance of martensite. In these cases, another heat treatment technique known
as tempering is performed on the quenched material in order to increase
the toughness of iron-based alloys. Tempering is usually performed after hardening, to reduce
some of the excess hardness, and is done by heating the metal to some temperature below
the critical point for a certain period of time, then allowing it to cool in still air.
Figure 4.1 Seal Quenched Furnace

41
CHAPTER-5
CONCLUSION
Two months industrial attachment with Volvo Eicher Commercial Vehicles has been one of
the most interesting, productive and instructive experience in my life. Through this training,
we have gained new insight and more comprehensive understanding about the real industrial
working condition and practice; it also improved my soft and functional skills. All these
valuable experiences and knowledge‟s that we have gained were not only acquired through
the direct involvement in task but also through other aspects of training such as: work
observation, interaction with colleagues, supervisors and other people related to the field. We
are sure that industrial training program has achieved its primary objectives. As result of this
training we are more confident to build our future career.

42
REFERENCES
 www.wikipedia.org
 www.vecv.in
 www.eicherworld.com
 Engineering Metrology – R.K. Jain
 Production Technology – R.K. Jain

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