International Journal of Engineering Trends and Technology (IJETT) – Volume2 Issue 1 Number2–Aug 2011
Study Of Three Speed Gear Box
Mr. ASHOKKUMAAR.A
Department of Mechanical Engineering,
Bharath institute of science and technology, Bharath University,
Chennai-600073,Tamilnadu
INTRODUCTION:
A machine consists of a power source and a power transmission system, which provides
controlled application of the power. Merriam-Webster defines transmission as an assembly of parts
including the speed-changing gears and the propeller shaft by which the power is transmitted from an
engine to a live axle. Often transmission refers simply to the gearbox that uses gears and gear trains to
provide speed and torque conversions from a rotating power source to another device.Most modern
gearboxes are used to increase torque while reducing the speed of a prime mover output shaft (e.g. a
motor crankshaft). This means that the output shaft of a gearbox will rotate at a slower rate than the input
shaft, and this reduction in speed will produce a mechanical advantage, causing an increase in torque. A
gearbox can be set up to do the opposite and provide an increase in shaft speed with a reduction of torque.
Some of the simplest gearboxes merely change the physical direction in which power is transmitted.
diagram of three speed gear box
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Specification
The gear box having involute six spur gear which maximum speed are 150 or minimum
speed is 300.to given structure formula we calculate the arrangement of gear and calculate
progression ratio is 2.236 ad different speed are 300,671&1500. Driver has 20 numbers of teeth
and pitch circle diameter of 30 mm. Driven gear is having 120 numbers of teeth and pitch circle
diameter 150 mm, both shafts is parallel to each other. The gear arrangement structural formula
is z=p1(x1)p2(x2)p3(x3)=3(1)1(3). The driver gear is manually rotated which leads to the
rotation of driven gearand when we shift the liver left and right wee got three different speed.
Components used in the fabrication of design in three speed gear box
a) Gears
b) Bearings
c) Shaft
d) Washer
e) Nuts and Bolts
f) Base, Handle, Column, liver
Gear
A gear is a rotating machine part having cut teeth, or cogs, which mesh with another
toothed part in order to transmit torque. Two or more gears working in tandem are called a
transmission and can produce a mechanical advantage through a gear ratio and thus may be
considered a simple machine. A gear or more correctly a "gear wheel" is a rotating machine part
having cut teeth which meshwith another toothed part in order to transmit torque. Two or more
gears working in tandem are called a transmission and can produce a mechanical
advantage through a gear ratio and thus may be considered a simple machine. Geared devices can
change the speed, torque, and direction of a power source. The most common situation is for a
gear to mesh with another gear; however a gear can also mesh a non-rotating toothed part, called
a rack, thereby producing translation instead of rotation.
When two gears of unequal number of teeth are combined a mechanical advantage is produced,
with both the rotational speeds and the torques of the two gears differing in a simple relationship.
In transmissions which offer multiple gear ratios, such as bicycles and cars, the term gear, as
in first gear, refers to a gear ratio rather than an actual physical gear. The term is used to describe
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similar devices even when gear ratio is continuous rather than discrete, or when the device does
not actually contain any gears, as in a continuously variable transmission.
Nomenclature of Gear
Types of Gears
1.Spur Gears
Spur gears are by far the most common type of gear and with the exceptions of the "cog" the type
of gear that has been around the longest. Spur gears have teeth that run perpendicular to the face of the
gear.
Spur gears or straight-cut gears are the simplest type of gear. They consist of a cylinder or disk
with the teeth projectingradically, and although they are not straight-sided in form, the edge of each tooth
is straight and aligned parallel to the axis of rotation. These gears can be meshed together correctly only if
they are fitted to parallel shafts.
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Spur gear
2. Helical Gears
Helical gears are very similar to spur gears except the teeth are not perpendicular to the face. The
teeth are at an angle to the face giving helical gears more tooth contact in the same area. Helical or "dry
fixed" gears offer a refinement over spur gears. The leading edges of the teeth are not parallel to the axis
of rotation, but are set at an angle. Since the gear is curved, this angling causes the tooth shape to be a
segment of a helix. Helical gears can be meshed in parallel or crossed orientations. The angled teeth
engage more gradually than do spur gear teeth causing them to run more smoothly and quietly.
The angled teeth engage more gradually than do spur gear teeth causing them to run more
smoothly and quietly.
3.Herringbone Gears
Herringbone gears resemble two helical gears that have been placed side by side. They
are often referred to as "double helical"
4. Bevel / Miter Gears
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Bevel gears are used mostly in situations that require power to be transmitted at right
angles (or applications that are not parallel). Bevel gears can have different angles of application
but tend to be 90°.
5. Worm gears
Worm gears are used to transmit power at 90° and where high reductions are required.
The worm resembles a thread that rides in concaved or helical teeth.
6. Internal Gears
Internal gears typically resemble inverted spur gears but are occasionally cut as helical
gears
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7. Racks
A rack is basically a straight gear used to transmit power and motion in a linear
movement.
Gear Material
Numerous nonferrous alloys, cast irons, powder-metallurgy and plastics are used in the
manufacture of gears. However steels are most commonly used because of their high strength to
weight ratio and low cost. Plastic is commonly used where cost or weight is a concern. A
properly designed plastic gear can replace steel in many cases because it has many desirable
properties, including dirt tolerance, low speed meshing, and the ability to "skip" quite well.
The module system
Countries which have adopted the metric system generally use the module system. As a
result, the term module is usually understood to mean the pitch diameter in millimeters divided
by the number of teeth. When the module is based upon inch measurements, it is known as
the English module to avoid confusion with the metric module. Module is a direct dimension,
whereas diametric pitch is an inverse dimension (like "threads per inch").
Bearing
A bearing is a device to allow constrained relative motion between two or more parts,
typically rotation or linear movement. Bearings may be classified broadly according to the
motions they allow and according to their principle of operation as well as by the directions of
applied loads they can handle.
Types of bearing
There are many types of bearings, each used for different purposes. These include ball
bearings, roller bearings, ball thrust bearings, roller thrust bearings and tapered roller thrust
bearings.
1. Ball Bearings
2. Roller Bearings
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3. Ball Thrust Bearing
4. Roller Thrust Bearing
5. Tapered Roller Bearings
Ball bearing
Ball bearings are widely used in a number of industrial applications. Extremely useful,
ball bearings are used to facilitate rolling elements for smooth radial or axial motion within a
spinning system. This type of bearing uses balls to maintain the separation between the moving
parts of the bearing. The ball bearing reduces rotational friction and support axial and radial
loads. Ball bearings reduce the amount of friction between components in a system and this helps
in the movement of heavier objects smoothly and with less effort. These ball bearings provide
smooth movement of parts or complete pieces of equipment.One of the least expensive types of
rolling element bearing is the ball bearing.
The cost of producing balls in these ball bearings is not very costly and hence ball bearings can be
found in everything from the washing machines to computers.
Features of ball bearings
1. The ball bearing system requires a thin film of lubricant for high-speed applications to reduce
friction and facilitate heat dissipation, corrosion prevention, and long bearing life.
2. The raceways and the balls both have a fine surface finish.
3. With proper lubrication, less noise, less torque and long life, all can be achieved in ball
bearings.
4. Ball bearings requireone time lubrication.
5. Ball bearings may fail due to improper lubrication, excessive temperature or if the bearing or
the raceway has been damaged.
Ball bearings assembly
All ball bearings are manufactured with four essential parts: the inner ring, the outer ring,
the rolling elements or balls, and the separator. The in-expensive ball bearings usually do not
have the separator , however this is very important and is a must in ball bearings to prevent
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rubbing contact between the bearing balls and side walls.
A ball bearing
Materials used in Making Ball Bearings
1. Stainless Steel
2. Chrome Steel
3. Ceramic
Series available in ball bearings
Manufacturers and suppliers produce ball bearings in various series:
Series 100: Extra light series
Series 200: Light series
Series 300: Medium series
Series 400: Heavy series
The size of the ball increases as the series increases and the larger size of the ball, the greater the
load carrying capacity. Most ball bearings are manufactured to meet every standards of
roundness, since any deformation can cause the moving parts to fail.
Applications of Ball Bearings
The application of ball bearings is seen.
1. Ball bearings are used in medical instruments, especially dental instrument. In dental and
medical hand tools, it is required that the pieces withstand sterilization and corrosion.
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Because of this requirement, they are made of 440 degree C stainless steel, which allows
smooth rotations at fast speeds.
2. It is said that ball bearings were very important to the German war industry during World
War II. The ball bearing factories were often a target of allied aerial bombings during war
time.
3. In aerospace industry, ball bearings are used on commercial, private and military aircraft ,
including gearboxes, pulleys and jet engine shafts.
4. The wheels in a skateboard contain two ball bearings in each of the four wheels.
5. Some manufacturers experimented with making balls in space on the space shuttle.
6. Applications for ball bearings include machine tools, precision spindles, radar mounts,
truck cranes and numerous others
Selection of used bearings
01. Deep groove ball bearings series 63
ISI No:-25BC03
Material: chrome steel
Boundary dimension
A: 25
B: 62
C: 17
Bearing Dimension
Shafts
A shaft is a rotating machine element which is used to transmit power from one place to
another place.
MATERIALS USED FOR SHAFTS
a) Should have high strength.
b) Should have good machinability.
c) Should have great heat treatment properties.
d) Should have high wear resistant properties.
The material used for ordinary shaft is carbon steel of grades 40C8, 45C8, 50C4 and 50C12.
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WASHER, BOLT & NUT
In the assembly we have taken two washer of mild steel, two M10 size bolts, one nut and bolt of
size M5 all made up of cast iron.
DESIGN AND CALCULATION
CALCULATION OF TEETH
The sliding block consists if three gears. For this block it is recommended that the number of teeth on
adjacent gears must differ by atleast four. This is to avoid interface of gears one shaft with the gears of the
other shaft while shifting. (Addendum circle of gears 1& 5 may foul on gear 4 while shifting the block
rightward and leftward respectively.)
(Z2 – Z5) > 4; (Z3 – Z1) > 4
Maximum reduction ray gives reduction from 300 rpm to 1500 rpm. Corresponding gears are 5 and 6.
Z5/Z6 = N6/N5 assume Z5 = 20 (driver)
20/ Z6 = 300 / 1500
Z6 = 100
Consider next ray line 1500 to 671 rpm
Z1 / Z2 = N2 / N1
Z1 / Z2 = 671 /1500
Z1 + Z2 = Z5+ Z6
Z1 + Z2 = 120
Z1 / Z2 = 0.488
Z1 = 0.488 * Z2
0.488 Z2 + Z2 = 120
1.448 Z2 = 120
Z2 = 120 / 1.448 = 82.87 = 83 (APPROX)
Z1 = 120 – 83 = 37
Next ray speed is 1500 to 1500
Z3 / Z4 = N3 / N4 = 1500 / 1500
Z3 = Z4
Z3 + Z4 = Z5 + Z6
2Z3 = 120
Z3= 60
Z4 = 60
CONDITION 1
Z3 – Z5> 4
60 – 20 > 4
40 > 4
CONDITION 2
Z3 – Z1> 4
60 – 37 > 4
23 > 4
So the conditions are getting satisfied
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Z1 = 37
Z2 = 83
Z3 = 60
Z4 = 60
Z5 = 20
Z6 = 100
CALCULATION OF MODULE
Assume power = 2.5 kw
Lowest speed is 300 rpm to obtained by the machine of gear 5 and 6. Therefore
Τ300rpm = (P * 60) / 2∏N
Τ300rpm =79.577=80kw
T = Ft6 * r6
r6 = pitch circle radius of gear 6
Therefore r6 = Z6 m / 2 = 100 m / 2 = 50 m
Now use the formula
m = (Ft / ψmM)
m2 = (Ft / ψmM)
Ft6 = T / r6
Where
Ft = tangential force on the pitch circle of the gear.
M = material constant making 80 for 15 Ni2 crl M 15
Ψm = gear transmission
Ψm = b / m = 10
m3= 1600/800=2
m=1.25=1.5(standard)
Calculate center distance of stage 1
a1 =( Z1 + Z2)m
2
= 90mm
Calculation center distance of stage 2
a2 = (Z5 + Z6) (m/2) = 90mm
LENGTH OF SHAFT
Distance between the gear and gear box wall is to be about 10 mm. Distance between the adjacent group
of gear is to be about 20 mm. Total length requirement for 2 pairs – group and 3 pair – group are to be 4b
and 7b respectively.
Thus the length of the shaft is obtained as
L = 30 + 10 + 4b + 20 + 7b + 20 + 7b + 10 + 30
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L=220
Calculate pitch circle diameter (d)
d = Zm
for gear 1 (d1) = Z1 * m =55.5
for gear 2 (d2) = Z2 * m =124.5
for gear 3 (d3) = Z3 * m =90
for gear 4 (d4) = Z4 * m =90
for gear 5 (d5) = Z5 * m =30
for gear 6 (d6 = Z6* m = 150
Calculate Tip diameter (da)
da = (Z + 2f0)m
f0 = 1 for full length(from design book)
for gear 1 (da1) = (Z1 + 2f0) m =58.5
for gear 2 (da2) =(Z2 + 2f0)m =127.5
for gear 3 (da3) = (Z3 + 2f0)m=93
for gear 4 (da4) = (Z4 + 2f0)m=93
for gear 5 (da5) = (Z5+ 2f0)m=33
for gear 6 (da6) = (Z6 + 2f0)m=153
Calculate root diameter (df)
df = (Z- 2f0)m – 2C
C = bottom clearance = 0.625
For gear 1 (df1) = (Z1 – 2f0)m – 2C=51.87
For gear 2 (df2) = (Z2 – 2f0)m – 2C=120.87
For gear 3 (df3) = (Z3 – 2f0)m – 2C=86.37
For gear 4 (df4) = (Z4 – 2f0)m – 2C=86.37
For gear 5 (df5) = (Z5 – 2f0)m – 2C=26.37
For gear 6 (df6) = (Z6 – 2f0)m – 2C=146.37
Shaft diameter calculation
Pressure angle(α)=20
Fn=ft/cosα
Fn=1135.12mm
Bm=fn*l =62.431Nm2
4
Tc=√Bm2+t62
Tc=101.47
16*Tc
∏ds3<40
ds3 =12919.56
ds =23.47=25(standard)
Bearing selection
 Series 63
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
ISI number 25BC03
D = 62
d = 25
r=2
B = 17
Bearing selection:
Inner diameter
Outer
in mm
diameter
Thickness
in mm
Basic load rating
Static
in mm
designation
Dynamic (C)
(Co)
25
62
17
1040
1660
SKF6305
DEEP GROOVE BALL BEARING
BASIC MACHINING OPERATION WHICH IS DONE ON LATHE MACHINE
Turning
Turning is the process whereby a single point cutting tool is parallel to the surface. It can
be done manually in a traditional form of lathe which frequently requires continuous supervision
by the operator or by using a computer controlled and automated lathe. This type of machine tool
is referred to as having computer numerical control, better known as CNC and is commonly used
with many other types of machine tool besides the lathe.
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When turning, a piece of material (wood, metal, plastic, or stone) is rotated and a cutting
tool is traversed along 2 axes of motion to produce precise diameters and depths. Turning can be
either on the outside of the cylinder or on the inside (also known as boring) to produce tubular
components to various geometries. Although now quite rare early lathes could even be used to
produce complex geometric figures even the platonic solids although until the advent of CNC it
had become unusual to use one for this purpose for the last three quarters of the twentieth century.
It is said that the lathe is the only machine tool that can reproduce itself.
Turning Operation
This operation is one of the most basic machining processes. That is, the part is rotated while a
single point cutting tool is moved parallel to the axis ofrotation. Turning can be done on the
external surface of the part as well as internally (boring). The starting material is generally a work
piece generated by
other processes such as casting, forging, extrusion, or drawing. It involves moving the cutting
tool at right angles to the axis of rotation of rotating work piece.
Turning operation
Facing
It is part of the turning process. It involves moving the cutting tool at right angles to the
axis of rotation of the rotating work piece. This can be performed by the operation of the crossslide, if one is fitted, as distinct from the longitudinal feed (turning). It is frequently the first
operation performed in the production of the work piece, and often the last- hence the phrase
"ending up".
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Facing operation
Grooving
Grooving is like parting, except that grooves are cut to a specific depth by a form tool
instead of severing a completed/part-complete component from the stock. Grooving can be
performed on internal and external surfaces, as well as on the face of the part (face grooving or
trepanning).
Grooving operation
Drilling
Drilling is used to remove material from the inside of a workpiece. This process utilizes
standard drill bits held stationary in the tail stock or tool turret of the lathe.
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Gear cutting Processes



1.1 Broaching
1.2 Hobbing
1.3 Machining
Broaching
`
For very large gears or splines, a vertical broach is used. It consists of a vertical rail that
carries a single tooth cutter formed to create the tooth shape. A rotary table and a Y axis are the
customary axes available. Some machines will cut to a depth on the Y axis and index the rotary
table automatically. The largest gears are produced on these machines.
Hobbing
Hobbing is a method by which a hob is used to cut teeth into a blank. The cutter and gear
blank are rotated at the same time to transfer the profile of the hob onto the gear blank. The hob
must make one revolution to create each tooth of the gear. Used very often for all sizes of
production runs, but works best for medium to high.
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Shaping
The old method of gear cutting is mounting a gear blank in a shaper and using a tool
shaped in the profile of the tooth to be cut. This method also works for cutting internal
splines.Another is a pinion-shaped cutter that is used in a gear shaper machine. It is basically
when a cutter that looks similar to a gear cuts a gear blank. The cutter and the blank must have a
rotating axis parallel to each other. This process works well for low and high production runs.
Welding
Welding is a fabrication or sculpturalprocess that joins materials, usually metals or
thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding
a filler material to form a pool of molten material that cools to become a strong joint, with
pressure sometimes used in conjunction with heat, or by itself, to produce the weld. This is in
contrast with soldering and brazing, which involve melting a lower-melting-point material
between the workpieces to form a bond between them, without melting the workpieces.
Many different energy sources can be used for welding, including a gas flame, an electric arc, a
laser, an electron beam, friction, and ultrasound. While often an industrial process, welding may
be performed in many different environments, including open air, under water and in outer space.
Welding is a potentially hazardous undertaking and precautions are required to avoid burns,
electric shock, vision damage, inhalation of poisonous gases and fumes, and exposure to intense
ultraviolet radiation.
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Types of Welding
Arc Welding
Arc welding is a type of welding that uses a welding power supply to create an electric
arc between an electrode and the base material to melt the metals at the welding point. They can
use either direct (DC) or alternating (AC) current, and consumable or non-consumable electrodes.
The welding region is usually protected by some type of shielding gas, vapor, and/or slag.
Gas metal arc welding
Gas metal arc welding (GMAW), sometimes referred to by its subtypes metal inert gas
(MIG) welding or metal active gas (MAG) welding, is a semi-automatic or automatic arc welding
process in which a continuous and consumable wireelectrode and a shielding gas are fed through
a welding gun. A constant voltage, direct current power source is most commonly used with
GMAW, but constant current systems, as well as alternating current, can be used. There are four
primary methods of metal transfer in GMAW, called globular, short-circuiting, spray, and pulsedspray,
each
of
which
has
distinct
properties
and
corresponding
advantages
and
limitations.Originally developed for welding aluminum and other non-ferrous materials in the
1940s, GMAW was soon applied to steels because it allowed for lower welding time compared to
other welding processes. The cost of inert gas limited its use in steels until several years later,
when the use of semi-inert gases such as carbon dioxide became common. Further developments
during the 1950s and 1960s gave the process more versatility and as a result, it became a highly
used industrial process. Today, GMAW is the most common industrial welding process, preferred
for its versatility, speed and the relative ease of adapting the process to robotic automation. The
automobile industry in particular uses GMAW welding almost exclusively. Unlike welding
processes that do not employ a shielding gas, such as shielded metal arc welding, it is rarely used
outdoors or in other areas of air volatility.
Gas tungsten arc welding
Gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding, is an arc
welding process that uses a nonconsumabletungstenelectrode to produce the weld. The weld area
is protected from atmospheric contamination by a shielding gas (usually an inert gas such as
argon), and a filler metal is normally used, though some welds, known as autogenous welds, do
not require it. A constant-currentwelding power supply
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ELECTRIC-ARC CUTTING
Electric-arc cutting is a method of melting or oxidizing metal by applying heat from an
electric arc to the work-metal surface along a line of cut. Because of the extremely high
temperature developed, the electric arc can be used to cut any metal that conducts electricity.
Modifications of the basic process include the use of compressed gases to cause rapid oxidation
(or to prevent oxidation) of the work metal, thus incorporating some aspects of gas cutting.
Electric-arc cutting includes several processes, of which the following are of commercial
importance: air-carbon arc cutting, oxygen arc cutting, plasma arc cutting, and the exo-process.
Other, seldom-used processes, which largely have been superseded by the aforementioned, are
briefly described in the last section of this article. Electric arc cutting can be used on ferrous and
nonferrous metals for rough severing, such as removing risers or scrap cutting, as well as for
more closely controlled operations. Each process has particular capabilities and limitations.
Special applications include shape cutting, grooving, gouging, and underwater cutting.
Operation on the part of the assemblies
GEAR
Facing, Taper turning, Drilling, broaching, hobbling, Gear tooth cutting of module 1.5.
SHAFT
Facing, Turning, Grooving, Drilling, 4key way sloting.
HANDLE
Facing, Turning, Drilling and internal thread cutting.
BASE & COLUMN
Drilling, Boring, Surface Grinding, Electric arc welding.
All operation has been done with specific dimension.
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COST ESTIMATION
COST OF THE STANDARD COMPONENTS
Sl.
Name of the components
Quality
Cost/piece in Rs.
Total cost in Rs.
Bearing (25 mm inner
04
122
488
No.
01
diameter)
02
Hexagonal M10 nut
04
12
48
04
M40 nut and bolt
03
02
06
TOTAL COST IN RUPEES
542
MATERIAL COST
Sl.
Name of the component
Material
Quantity
Cost in rupees
01
Gear
Mild steel
06
360
02
Shaft
Mild steel
02
140
03
Supporting plate of base
Mild steel
01
95
04
Supporting plate for column
Mild steel
02
190
06
Handle
Mild steel
01
40
07
Bed
Mild steel
01
250
08
Washer
Mild steel
02
20
09
Liver
Mild steel
01
750
No.
TOTAL COST IN RUPEES
1845
MACHINING COST
Sl.
Machine
Operation
Cost in rupees
No.
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01
Gear teeth cutting
Gear
9000
Hibbing
02
Shaft
Turning faceing
03
Spine shaft
200
4 key way spline shaft
04
Lathe (finishing)
0
Fabrication and assembly
01. Lathe
1350
Facing, turning, finishing
600
Facing, turning, grooving
750
Arc welding
300
Drilling
200
Surface finishing
150
02. Welding
03. Milling machine
04. Grinding
machine
TOTAL COST IN RUPEES
12550
TOTAL COST OF DESIGN AND FABRICATION OF THREE SPEED GEAR BOX
Sl.
Particular
Cost in rupees
01
Cost of standard component
542
02
Material cost
1845
03
Machining cost
12550
04
Transportation and allowances
900
05
Name plate and painting
200
No.
TOTAL COST IN RUPEES
16037
PART AND ASSEMBLY DRAWING
1. Nut
2. Bolt
3. Bearing
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International Journal of Engineering Trends and Technology (IJETT) – Volume2 Issue 1 Number2–Aug 2011
4. Shaft
5. Gear
6. Base support
7. Column
8. Washers
9. Assembly Drawing
Nut
Bolt
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International Journal of Engineering Trends and Technology (IJETT) – Volume2 Issue 1 Number2–Aug 2011
Bearing
spineShaft
spurGear
ISSN: 2231-5381
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International Journal of Engineering Trends and Technology (IJETT) – Volume2 Issue 1 Number2–Aug 2011
Bills of the materials:
Sl.No.
Part Description
Quantity
Material
01
Gear
06
Mild steel
02
Bearing
04
Mild steel
03
Shaft
02
Mild steel
04
Base support
01
Mild steel
Liver
01
Mild steel
07
Supporting plate
02
Mild steel
08
Nut
04
Cast iron
09
Bolt
04
Cast iron
10
Handle
01
Mild steel
11
Washer
02
Mild steel
SNAPSHOTS:
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International Journal of Engineering Trends and Technology (IJETT) – Volume2 Issue 1 Number2–Aug 2011
ISSN: 2231-5381
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International Journal of Engineering Trends and Technology (IJETT) – Volume2 Issue 1 Number2–Aug 2011
REFERENCES
1. Gitin M Maitra, (2002) ‘Hand book of gear design’second edition,
2. S.K.F Industries (1991) ‘ bearing design table’p.p 9-10
3. T.Jayachandraprabhu (2011) ‘ design of transmission elements’gear box page no:20.4
WORK PLACE ADDRESS:
01. NEW DELTA GEAR PVT. LTD.
PALLAVAN, CHENNAI- 600032
02. S.R.M. ENGINEERING WORKS
No. – 30/27, POONAMALLIEE ROAD,
EKKATTUTHANGAL, CHENNAI-600032
ISSN: 2231-5381
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