DESIGN AND FABRICATION OF ROLLING MACHINE WITH SPLINES
A dissertation submitted in partial fulfillment for the award of
the degree of
BACHELOR OF ENGINEERING
in
MECHANICAL ENGINEERING
Submitted by
ABDUL SALAM.A92509144001
KADER BATCHA.A92509144021
Under the Guidance of
Asst. Prof. D. PALANISAMY M.E
DEPARTMENT OF MECHANICAL ENGINEERING
ANNA UNIVERSITY OF TECHNOLOGY TIRUCHIRAPPALLI
TIRUCHIRAPPALLI – 620 024
April-2012
M.A.R. COLLEGE OF ENGINEERING AND TECHNOLOGY
Viralimalai - 621316
BONAFIDE CERTIFICATE
This is to certify that this is the bonafide of DESIGN AND
FABRICATION PROJECT carried out by ABDUL SALAM.A and KADAR BATCHA
.A Reg. No 92509144001 & 92509144021 in VI semester/ III year
during 2011 – 2012.
HEAD OF THE DEPARTMENTINTERNAL GUIDE
PROJECT CO – ORDINATOR
Submitted for the university practical examination held on
Internal Examiner External Examiner
ACKNOWLEDGEMENT
First of all we thank our god for his Shower of blessings and
his Divine help which enables us to complete the project
successfully.
We are extremely thankful to our parents for enlightening us by
providing professional education and for their prayerful support
that makes us to complete the project.
We extend our sincere thanks to Alhaj Er. A. Mohamed Yunus B.E.,
M.Sc., (Engg.) Founder & Chairman, M.A.R College of Engineering
and Technology, Viralimalai, for offering the means of attaining
our most cherished goal and Environment
We extend our deepest gratitude to Principal Dr A. Edgar Ruskin
Frank Ph.D, M.A.R College of Engineering & Technology,
Viralimalai for giving us permission to do the project work
successfully,
We are grateful to express our profound thanks to S.SOMASUNDARAM
M.E, Head of Department, M.A.R College of Engineering &
Technology, Viralimalai, who has been a source of encouragement and
moral strength throughout our study period.
It gives immense pleasure to extend my sincere and heartfelt
gratitude to project guide Mr.D.PALANISAMY M.E, Assistant Professor
for his untiring, valuable and timely suggestion in dispensable
situation during the period of study.
Also heartfelt thanks to our friends, Teaching and Non Teaching
Staff members who helped us to finish the project work
successfully.
TABLE OF CONTENTS
CHAPTER NO.TITLE PAGE NO
ABSTRACT 6
LIST OF TABLE 7
LIST OF FIGURES 8
1. INTRODUCTION
1.1 . GENERAL 9
1.2 DEFINITIONS 10
1.3 TYPE OF ROLLING 12
1.3.1 Hot rolling 12
1.3.3 Cold rolling 13
1.4 TYPES OF ROLLING PROCESS 14
1.4.1 Roll bending 14
1.3.2 Roll forming 15
1.3.3 Flat rolling 15
1.3.4 Foil rolling 16
1.3.5 Ring rolling 17
1.3.6 Structural shape rolling 18
1.3.7 Controlled rolling 18
2. LITERATURE REVIEW 19
2.1 Forces and geometrical relationships in rolling19
2.2 Terminology24
2.3 Products27
2.4 Rolls28
2.5 Rolling mills30
2.5.1 Modern Rolling Mill30
2.6 DESIGN CALCULATION31
2.6.1 Dimension Of The Rolling Components312.7 Fabrication Of
Rolling Machine33
2.7.1 Machining Operations34
2.8 FURTHER OPERATION35
2.9 BILL OF materials36
2.10 COST ESTIMATION 37
2.10.1 Material cost 372.10.2. Machining cost38
2.10.3 Over heads
2.10.4 Total cost 38
3.CONCLUSION
4.REFERENCES
ABSTRACT
Rolling is the process in which the metal and alloys are
plastically deformed into semi-finished or finished condition, by
passing these between circular or contoured rotating cylinder
(rolls).the metals is drawn into the opening between the rolls by
frictional force s between the metal and the roll surface. In
deforming metal between rolls, the workpiece is subjected to high
compressive force from the squeezing action of rolls.
In metalworking rolling is a metal forming process in which
metal stock is passed through a pair of rolls. Rolling is
classified according to the temperature of the metal rolled. If the
temperature of the metal is above its recrystallization
temperature, then the process is termed as hot rolling. If the
temperature of the metal is below its recrystallization
temperature, the process is termed as cold rolling. In terms of
usage, hot rolling processes more tonnage than any other
manufacturing process and cold rolling processes the most tonnage
out of all cold working processes.
Project is based on the need for rolling the sheet metal with
splines design This design and fabrication purpose of rolling and
designing the sheet metal.
OUR PROJECT HAVE THE FOLLOWING OBJECTIVES:
This rolling machine is used to roll the sheet metals with
splines and to improve the strength of the sheet metals. Rolling
machine is device which used for rolling the sheet metal. The sheet
metals can be easily rolled. Even an unskilled technician can use
them,With these features, we sincerely hope that our project serve
as a valuable project. Welcome the correction, comments based on
our project.
LIST OF TABLE
NO DESCRIPTION PAGE NO
Table 1 Bill of materials 36
Table 2 Material cost 37
Table 3 Machining cost 38
LIST OF FIGURES
N0 DESCRIPTION PAGE NO
Fig 1 Rolling Machine 10
Fig 2 Process Of Rolling Machine 11
Fig 3 Rolled Strips. 11
Fig 4 A Coil Of Hot-Rolled Steel 12
Fig 5 Process Of Rolling 14
Fig 6 Roll Forming 15
Fig 7 A Schematic Of Ring Rolling 16
Fig 8 Cross-Sections Of Continuously Rolled Structural
Shapes Showing The Change Induced By Each
Rolling Mill. 18
1. INTRODUCTION
1.1. GENERAL
Steel is initially produced in 20 cm thick slabs. Steel in this
form is usually processed
further before being sold to customers. This generally involves
rolling it into thinner
sheets (and sometimes forming it into tubes). This steel is now
conveniently shaped, but is
prone to rusting so for applications where it is exposed to the
weather it is often galvanized
(and sometimes painted as well) to prevent corrosion.
Step 1 - Hot Rolling
In the hot rolling process, slabs are reheated and fed into the
rough rolling mill where it is reduced from 210mm to 25mm
thickness. The thin sheets are then wound onto spools to
make 'coils' of rolled steel.
Step 2 - Cold Rolling
Hot rolled coils are welded into continuous sheets, and the iron
oxides that have formed in
hot rolling removed with hydrochloric acid:
Fe2O3⋅xH2O + 6HCl → 2FeCl3 + (x+3)H2O
The sheets are then oiled to prevent further corrosion and
rolled. This rolling further
reduces the thickness of the sheets and gives them a smoother
surface.
Step 3 - Galvanising
Hot alkali solutions are used to remove the remaining grease,
then the steel is treated with
acid to clean and etch the surface. The steel is repeatedly
heated and cooled to strengthen
it and then galvanised by dipping it in zinc. The steel can then
be used as is for roofing, or
further processed.
Step 4 - Paint Coating
The steel is again cleaned and then coated with primer. Solvent
in the primer is evaporated by a hot air jet and the paint baked
on. Finish coat is then applied, baked and
cured on top of the primer coating. Different grades of
finishing paint are used for
different applications.
1.2 DEFINITIONS
Definition of Rolling : The process of plastically deforming
metal by passing it between rolls. Rolling is the most widely used
forming process, which provides high production and close control
of final product. The metal is subjected to high compressive
stresses as a result of the friction between the rolls and the
Rolling process metal surface.
SHEET METAL ROLLING MACHINE:
fig 1 rolling MACHINE.
The rolling machine without splines in various industries.
fig.2 process of rolling machine
fig 3 rolled strips.
Finished rolled sheet metals
1.3 TYPE OF ROLLING
1.3.1 Hot rolling
Fig 4. A Coil of Hot-Rolled Steel
Hot rolling is a metalworking process that occurs above the
recrystallization temperature of the material. After the grains
deform during processing, they recrystallize, which maintains an
equiaxed microstructure and prevents the metal from work hardening.
The starting material is usually large pieces of metal, like
semi-finished casting products, such as slabs, blooms, and billets.
If these products came from a continuous casting operation the
products are usually fed directly into the rolling mills at the
proper temperature. In smaller operations the material starts at
room temperature and must be heated. This is done in a gas- or
oil-fired soaking pit for larger work pieces and for smaller work
pieces induction heating is used. As the material is worked the
temperature must be monitored to make sure it remains above the
recrystallization temperature. To maintain a safety factor a
finishing temperature is defined above the recrystallization
temperature; this is usually 50 to 100 °C (90 to 180 °F) above the
recrystallization temperature. If the temperature does drop below
this temperature the material must be re-heated before more hot
rolling.
Hot rolled metals generally have little directionality in their
mechanical properties and deformation induced residual stresses.
However, in certain instances non-metallic inclusions will impart
some directionality and work pieces less than 20 mm
(0.79 in) thick often have some directional properties. Also,
non-uniformed cooling will induce a lot of residual stresses, which
usually occurs in shapes that have a non-uniform cross-section,
such as I-beams and H-beams. While the finished product is of good
quality, the surface is covered in mill scale, which is an oxide
that forms at high-temperatures. It is usually removed via pickling
or the smooth clean surface process, which reveals a smooth
surface. Dimensional tolerances are usually 2 to 5% of the overall
dimension.
Hot rolled mild steel seems to have a wider tolerance for amount
of included carbon than cold rolled, making it a bit more
problematic to use as a blacksmith. Also for similar metals, hot
rolled seems to typically be more costly.
Hot rolling is used mainly to produce sheet metal or simple
cross sections, such as rail tracks.
1.3.2 Cold rolling
Cold rolling occurs with the metal below its recrystallization
temperature (usually at room temperature), which increases the
strength via strain hardening up to 20%. It also improves the
surface finish and holds tighter tolerances. Commonly cold-rolled
products include sheets, strips, bars, and rods; these products are
usually smaller than the same products that are hot rolled. Because
of the smaller size of the work pieces and their greater strength,
as compared to hot rolled stock, four-high or cluster mills are
used. Cold rolling cannot reduce the thickness of a work piece as
much as hot rolling in a single pass.
Cold-rolled sheets and strips come in various conditions:
full-hard, half-hard, quarter-hard, and skin-rolled. Full-hard
rolling reduces the thickness by 50%, while the others involve less
of a reduction. Skin-rolling, also known as a skin-pass, involves
the least amount of reduction: 0.5-1%. It is used to produce a
smooth surface, a uniform thickness, and reduce the yield point
phenomenon (by preventing Lüders bands from forming in later
processing). It locks dislocations at the surface and thereby
reduces the possibility of formation of Lüders bands. To avoid the
formation of Lüders bands it is necessary to create substantial
density of unpinned dislocations in ferrite matrix. It is also used
to breakup the spangles in galvanized steel. Skin-rolled stock is
usually used in subsequent cold-working processes where good
ductility is required.
Other shapes can be cold-rolled if the cross-section is
relatively uniform and the transverse dimension is relatively
small. Cold rolling shapes requires a series of shaping operations,
usually along the lines of sizing, breakdown, roughing,
semi-roughing, semi-finishing, and finishing.
If processed by a blacksmith, the smoother, more consistent, and
lower levels of carbon encapsulated in the steel makes it easier to
process, but at the cost of being more expensive
1.3 TYPES OF ROLLING PROCESS :
1.3.1Roll bending
fig 5. Roll bending
Roll bending produces a cylindrical shaped product from plate or
steel metal.
1.3.2 Roll forming
fig 6. Roll forming
Roll forming is a continuous bending operation in which a long
strip of metal (typically coiled steel) is passed through
consecutive sets of rolls, or stands, each performing only an
incremental part of the bend, until the desired cross-section
profile is obtained. Roll forming is ideal for producing parts with
long lengths or in large quantities. There are mainly 3 main
processes, 4 rollers, 3 rollers and 2 rollers, and have different
advantages according to the specifications of the plate (thickness
length and diameter) and the shapes.
Also call roll bending or plate rolling process this is used in
many fields, Exhaust pipes, Trucks brakes, Pressure Vessel Tanks
Gaz tanks, Components for airbags, Fire extinguishers, Hot water
boilers, Drawer rails, Filter housings, Fittings, Fuel filters,
Gear components, Gear selector forks, Multi diameter Shells,
Pressurized containers, Pumps' shells, Rear axles, Sink mountings,
Spinning compatible tubes, Washing drumbs.
1.3.3 Flat rolling
Flat rolling is the most basic form of rolling with the starting
and ending material having a rectangular cross-section. The
material is fed in between two rollers, called working rolls, that
rotate in opposite directions. The gap between the two rolls is
less than the thickness of the starting material, which causes it
to deform. The decrease in material thickness causes the material
to elongate. The friction at the interface between the material and
the rolls causes the material to be pushed through. The amount of
deformation possible in a single pass is limited by the friction
between the rolls; if the change in thickness is too great the
rolls just slip over the material and do not draw it in. The final
product is either sheet or plate, with the former being less than
6 mm (0.24 in) thick and the latter greater than;
however, heavy plates tend to be formed using a press, which is
termed forming, rather than rolling.[
Oftentimes the rolls are heated to assist in the workability of
the metal. Lubrication is often used to keep the workpiece from
sticking to the rolls. To fine tune the process the speed of the
rolls and the temperature of the rollers are adjusted.
1.3.4 Foil rolling
Foil rolling is a specialized type of flat rolling, specifically
used to produce foil, which is sheet metal with a thickness less
than 200 µm (0.0079 in). The rolling is done in a cluster
mill because the small thickness requires a small diameter rolls.
To reduce the need for small rolls pack rolling is used, which
rolls multiple sheets together to increase the effective starting
thickness. As the foil sheets come through the rollers, they are
trimmed and slitted with circular or razor-like knives. Trimming
refers to the edges of the foil, while slitting involves cutting it
into several sheets. Aluminum foil is the most commonly produced
product via pack rolling. This is evident from the two different
surface finishes; the shiny side is on the roll side and the dull
side is against the other sheet of foil.
1.3.5 Ring rolling
fig 7. A schematic of ring rolling
Ring rolling is a specialized type of hot rolling that increases
the diameter of a ring. The starting material is a thick-walled
ring. This workpiece is placed between two rolls an idler roll,
while another roll, called the driven roll, presses the ring from
the outside. As the rolling occurs the wall thickness decreases as
the diameter increases. The rolls may be shaped to form various
cross-sectional shapes. The resulting grain structure is
circumferential, which gives better mechanical properties.
Diameters can be as large as 8 m (26 ft) and face heights
as tall as 2 m (79 in). Common applications include
rockets, turbines, airplanes, pipes, and pressure vessels.
1.3.6 Structural shape rolling
fig 8. Cross-sections of continuously rolled structural shapes,
showing the change induced by each rolling mill.
1.3.7 Controlled rolling
Controlled rolling is a type of thermomechanical processing
which integrates controlled deformation and heat treating. The heat
which brings the workpiece above the recrystallization temperature
is also used to perform the heat treatments so that any subsequent
heat treating is unnecessary. Types of heat treatments include the
production of a fine grain structure; controlling the nature, size,
and distribution of various transformation products (such as
ferrite, austenite, pearlite, bainite, and martensite in steel)
inducing precipitation hardening and, controlling the toughness. In
order to achieve the entire process must be closely monitored and
controlled. Common variables in controlled rolling include the
starting material composition and structure, deformation levels,
temperatures at various stages, and cool-down conditions. The
benefits of controlled rolling include better mechanical properties
and energy savings.
2. LITERATURE REVIEW
2.1 Forces and geometrical relationships
in rolling :
• A metal sheet with a thickness ho enters
the rolls at the entrance plane xx with a
velocity vo.
• It passes through the roll gap and leaves
the exit plane yy with a reduced thickness
hf and at a velocity vf.
• Given that there is no increase in
width, the vertical compression of the
metal is translated into an elongation in
the rolling direction.
• Since there is no change in metal
volume at a given point per unit time
throughout the process, therefore
bhovo = bhv = bhf vf …Eq.1
Where b is the width of the sheet
v is the velocity at any thickness h intermediate between ho and
hf.
From Eq.1
Bhovo = bhf vf
Given that bo = bf
Ho = hf
Then we have
voho = vf hf
…Eq.2
When ho > hf , we then have vo < vf
The velocity of the sheet must steadily increase
from entrance to exit such that a vertical elementin the sheet
remain undistorted.
• At only one point along the surface of contact between the
roll and the
sheet, two forces act on the metal: 1) a radial force Pr and 2)
a tangential frictional force F.
• If the surface velocity of the roll vr equal to the velocity
of the sheet, this
point is called neutral point or no-slip point. For example,
point N.
• Between the entrance plane (xx) and the neutral point the
sheet is moving slower than the roll surface, and the tangential
frictional force, F, act in the direction (see Fig) to draw the
metal into the roll.
• On the exit side (yy) of the neutral point, the sheet moves
faster than the roll surface. The direction of the frictional fore
is then reversed and
oppose the delivery of the sheet from the rolls. Pr is the
radial force, with a vertical
component P (rolling load - the load with which the rolls press
against the metal).
The specific roll pressure, p, is the rolling load divided by
the contact area.
P= …Eq.3
Where, b is the width of the sheet.
Lp is the projected length of the arc of contact.
(ho-hf)(ho-hf) / 4]^1/2 = [R(ho-hf)]^2 …Eq.4
• The distribution of roll pressure along the arc of contact
shows that the pressure rises to a maximum at the neutral point and
then falls off.
• The pressure distribution does not come to a sharp peak at the
neutral
point, which indicates that the neutral point is not really a
line on the roll
surface but an area.
• The area under the curve is proportional to the rolling
load.
• The area in shade represents the force required to overcome
frictional forces between the roll and the sheet.
• The area under the dashed line AB represents the force
required to deform the metal in plane homogeneous compression.
Simplified analysis of rolling load
The main variables in rolling are:
• The roll diameter.
• The deformation resistance of the metal as influenced by
metallurgy,
temperature and strain rate.
• The friction between the rolls and the workpiece.
• The presence of the front tension and/or back tension in the
plane of the
sheet.
We consider in three conditions:
1) No friction condition
2) Normal friction condition
3) Sticky friction condition.
• Frictional force is needed to pull the metal into the rolls
and responsible for a large portion of the rolling load.
• High friction results in high rolling load, a steep friction
hill and great tendency for edge cracking.
• The friction varies from point to point along the contact arc
of the roll. However it is very difficult to measure this variation
in μ, all theory of rolling are forced to assume a constant
coefficient of friction.
• For cold-rolling with lubricants, μ ~ 0.05 – 0.10.
• For hot-rolling , μ ~ 0.2 up to sticky condition.
Problems and defects in rolled products
Defects from cast ingot before rolling
• Porosity, cavity, blow hole occurred in the cast ingot will be
closed up
during the rolling process.
• Longitudinal stringers of non-metallic inclusions or pearlite
banding are related to melting and solidification practices. In
severe cases, these defects can lead to laminations which
drastically reduce the strength in the thickness direction. Defects
other than cracks can result from defects introduced during the
ingot stage of production.
under high rolling forces, the rolls flatten and bend, and the
entire mill is elastically
distorted.
• Mill spring causes the thickness of the sheet exiting from the
rolling mill to be
greater than the roll gap set under no-load conditions.
• Precise thickness rolling requires the elastic constant of the
mill. Calibration
curves are needed, see Fig. (1–3 GNm-1 for screw-loaded rolling
mills, 4
GNm-1 for hydraulically loaded mills).
2.2 Terminology
• Bloom is the product of first breakdown of ingot
(cross sectional area > 230 cm2).
• Billet is the product obtained from a further reduction by hot
rolling
(cross sectional area > 40x40 mm2).
• Slab is the hot rolled ingot
(cross sectional area > 100 cm2 and with a width ≥ 2 x
thickness).
Solutions to flatness problems
• Camber and crown can be used to correct the roll deflection
(at only one
value of the roll force). Or use rolling mill equipped with
hydraulic jacks to
permit the elastic distortion of the rolls to correct
deflection.
fig 8 process of rolling
• Hot mill can be provided with facilities for crown control to
improve the control of the profile of hot strip mill.
• For example work roll bending with continuous variable crown
and pair cross
mills.
•The roll cross angle of rolls incorporated in a stand of each
rolling mill is set at a
predetermined value beforehand.
• If there is a roll cross angle that will enable a target sheet
crown to be applied
to each sheet and the roll bender load of each stand is adjusted
on-line, thereby
effecting sheet crown control.
Thickness measurement in continuous
COLD STRIP MILLS
fig. sensor rolling
• Thickness is measured by x-ray gauges while the error in the
thickness following the first tand is usually fedback to adjust the
gap sitting on the first stand.
• Gauge control in subsequent stands usually is achieved by
controlling the
strip tension through controlling the relative roll speed in
successive stands
or the coiler speed.
• Gauge control through control of strip tension has faster
response
time than control through change in roll setting.
2.3 Products:
• Plate is the product with a thickness > 6 mm.
• Sheet is the product with a thickness < 6 mm and width >
600 mm.
• Strip is the product with a thickness < 6 mm and width <
600 mm.
Mill products Further rolling steps
· Bloom Billet Slap
· Plate Sheet Strip
2.4 ROLLS :
ROLLING WITH SPLINES
2.5 ROLLING MILLS
2.6.2 DESIGN PROCEDURE
A rolling mill basically consists of
1. Rolls
2. Bearings
3. a housing for containing these parts
4. a drive (motor) for applying power to the rolls and
controlling the speed.
2.5.1 MODERN ROLLING MILL :
1. Requires very rigid
2. Construction , large motors to supply enough power (MN).
Successive stands of a large continuous mill
2.6 DESIGN CALCULATION
2.6.1 DIMENSION OF THE ROLLING COMPONENTS:
1. Length of hollow pipe = 300 mm
2. diameter of hollow pipe = 40 mm
3 MS – rod length = 300 mm
4. MS –rod diameter = 40 mm
6. Pipe rings thickness = 5 mm
2.6.2.1 SELECTION OF ROLLER
A roller is to be selected for making a rolls the sheet metal is
required diameter = 40 mm and length =300mm
2.6.2.2 SELECTION OF GEARS
We can go for the spur gears for the three rollers to transmit
the power to the rollers from the rotating handle.
FINISHED JOB
Fig. FINISHED JOB
2.7 FABRICATION OF ROLLING MACHINE
There are few types of fabrication methods are done on this
rolling machine.
They are,
1. Drilling
2. Turning
3. Grinding
4. Chamfering
5. Milling
6. Boring
7. Grooving
8. Welding
2.7.1 MACHINING OPERATIONS:
Drilling
Drilling is used to produce holes in objects. In this project
the jig plates requires the holes for making bolted assembly. Also
to fitting the bushes holes are required. These holes are done by
conventional vertical type drilling machine.
Fine grinding
It is nothing but the grinding process, which is done as smooth
with fine grains. This is done as the each plate and flanges for
good surface finish. It is done by conventional grinding
machine.
Chamfering
It is the process used to smooth the sharp edges. It is required
in the fabrication processes in order to avoid scratches made by
the parts. In this project it is used to smooth the sharp edges of
the gas cutted plates.
Welding
It is the process, which is used to join two, is more similar
materials as well as dissimilar materials. In this project it is
used to join the round flanges with the l-bow pipe to make the work
piece. This is done by arc welding machine.
Boring
Boring is the process which is used to make material removal
internally. In this project it is used to boring on the two cover
plates to hold the l-bow with flange. Through bores are also
produced on the two cover plates. This is done by using lathe.
Milling
Milling is used to machine curved surfaces. In this project the
flanges for elbow pipe and supporting blocks need curved surfaces.
This is done by using conventional milling machine.
Grooving
It is used in this project to make the groove on the both sides
of top cover plate. This is done by conventional lathe.
2.8 FURTHER OPERATIONS
· Cleaning
It is the operation to clean the all machined parts without
burrs, dust and chip formals. By meaning the parts they are
brightened and good-looking.
· Assembling
It is the operation, which deals with the assembling of various
parts produced by above operations.
2.9 BILL OF materials
Table 1
SNO
PART NAME
MATERIAL
NO.OFF
1
Hollow pipe
G.I
2
2
Rod
Mild steel
1
3
Plate
Mild steel
2
4
Spur gear
Mild steel
3
5
shaft
Mild steel
3
6
Sheet (raw material)
Galvanized iron
1
2.10 COST ESTIMATION
2.10.1 MATERIAL COST:
Table 2
S.NO
COMPONENTS
QUANTITY
COST
1
Hollow pipe
2
RS.120
2
Rod
1
RS.150
3
Plate
2
RS.50
4
Spur gear
3
RS.350
5
Job
1
Rs.75
Total
Rs. 745
2.10.2 MACHINING COST:
Table 3
S.NO
MACHINING OPERATION
COST
1
LATHE WORK
Rs. 300
2
DRILL WORK
Rs.125
3
MILLING WORK
Rs.175
4
WELDING WORK
Rs.150
5
GRINDING WORK
Rs.125
TOTAL
Rs.875
2.10.3 OVER HEADS:
MACHINING COST = Rs.875
TRANSPORTATION COST = Rs. 200
____________
TOTAL = Rs.1075
____________
2.10.4 TOTAL COST:
Material cost = Rs.745
Overheads = Rs.1075
Total = Rs.1820
2.11 Problems and defects in rolled products
Defects from cast ingot before rolling
• Porosity, cavity, blow hole occurred in the cast ingot will be
closed up
during the rolling process.
• Longitudinal stringers of non-metallic inclusions or pearlite
banding
are related to melting and solidification practices. In severe
cases, these
defects can lead to laminations which drastically reduce the
strength in the
thickness direction.
3. CONCLUSION
This report deals with the design and fabrication of Rolling
machine and the detailed drawing of the component and assembles.
The project carried out by us made an impressing task in forming
process. It is very useful in sheet metal industries for mass
production.
4. References:
• Dieter, G.E., Mechanical metallurgy, 1988, SI metric
edition,
McGraw-Hill, ISBN 0-07-100406-8.
• Edwards, L. and Endean, M., Manufacturing with materials,
1990,
Butterworth Heinemann, ISBN 0-7506-2754-9.
• Beddoes, J. and Bibbly M.J., Principles of metal
manufacturing
process, 1999, Arnold, ISBN 0-470-35241-8.
• Lecture note, 2003.
• Firth Rixson leavelets.
• Metal forming processes, Prof Manas.
• Metal forming lecture, Ass Prof. P. Srichareonchai.
38