VOCATIONAL TRAINING REPORT OF SIMPLE CASTING LIMITED
İlker ALTINSOY-ME299
1. 1
GAZİANTEP ÜNİVERSİTESİ
UNIVERSITY OF GAZİANTEP
MÜHENDİSLİK FAKÜLTESİ
FACULTY OF ENGINEERING
MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ
DEPARTMENT OF MECHANICAL ENGINEERING
ME 299 YAZ STAJI PROGRAMI
ENGINEERING PRACTICE PROGRAMME
Prepared by İlker ALTINSOY
2. 2
CONTENTS
Page Number
Description of The Company……………………………………………………4
1. The Name of The Company……………………………………………..…..4
2. Contact Information of The Company……………………………..………4
3. Number of Workers and Engineers Employed at The Company………...4
4. Organization Structure of The Company……………………………….…4
5. Information About Company……………………………………………….5
Introduction…………………………………………………………………...…6
Forging Department. …………………………………………………………...7
1. Forging Process………………………………………………………..……8
1.1. Drop Forging……………………………………………………….…..8
1.2. Press Forging…………………………………………………...………9
1.3. Upset Forging…………………………………………………….……10
1.4. Roll Forging……………………………………………………………11
2. How Does Forging Department Work at ÇİMSATAŞ…………………...12
2.1. Die DesignDepartment………………………………………………..12
2.2. Die Machining Department…………………………………..….……13
2.3. Press Department………………………………………………...……13
2.4. Some of Work-Pieces Which is Forged in Forging Department……15
Foundry Department…………………………………………………………..17
1. Basic Processes………………………………………………………………18
2. Pattern Making……………………………………………………………...20
2.1. Parts of the Pattern………………………………………………….…20
2.2. Terms……………………………………………………………………22
Machining Department…………………………………………………………22
1. Machining on Lathe…………………………………………………………23
1.1. Facing……………………………………………………………………24
1.2. Drilling…………………………………………………………………..24
1.3. Boring……………………………………………………………………26
3. 3
1.4. Parting…...………………………………………………………………26
1.5. Turning…………………………………………………………..………….27
1.6. Some of Work-Pieces Which is Processedin Machining Department…..28
2. Machining on a Milling Machine……………………………………………….30
2.1. Parts of The Milling Machine………………………………………………31
3. Differences Between Milling Machine and Lathe………………………………32
4. Some Machines and Their Technical Specifications at ÇİMSATAŞ…………32
Heat Treatment Department…………………………………………………………33
1. Heat Treatment Processes at ÇİMSATAŞ……………………………………..34
1.1. Normalizing………………………………………………………………….35
1.2. Annealing…………………………………………………………………….36
1.3. Tempering……………………………………………………………………37
1.4. Cementation…………………………………………………………………39
1.5. Induction Hardening……………………………………………………….40
Conclusion……………………………………………………………………………41
Appendix A…………………………………………………………………………..42
Appendix B…………………………………………………………………………..43
Appendix C…………………………………………………………………………..44
4. 4
DESCRIPTION OF THE COMPANY
1. The Name of The Company
Cukurova Insaat Makinaları San. ve Tic. A.S.
ÇİMSATAŞ
2. Contact Informations of The Company
Address:
Mersin Tarsus Karayolu 11.Km P.K.634 33004 Mersin / Türkiye
Tel : +90(324) 221 84 00 (Pbx)
Fax : +90(324) 221 84 04 - 05
E-Mail : cimsatas@cimsatas.com
3. Number of Workers and Engineers Employed at The Company
3.1. Number of Worker : 560
3.2. Number of Engineer : 42
3.2.1. Number of Mechanical Engineer : 22
3.2.2. Number of metallurgical Engineer : 14
3.2.3. Number of Industrial Engineer : 4
3.2.4. Number of Electronic Engineer : 1
3.2.5. Number of Chemical Engineer : 1
3.3. Total Employers : 658
4. Organization Structure of The Company
Organization structure of the company is given in Appendix A.
5. 5
5. Information About Company
Part of to Cukurova Group which is one of the leading Turkish business conglomerates
within the core business areas of industry, construction, communication and information
technology, media, transport, financial services and energy.
The company is well integrated with Ferrous Foundry, Forge-shop, Machining, Heat
Treatment facilities and Heavy Duty Air Brake System production lines.
Cimsatas serves as a major supplier to local and European automotive industry,
construction machine industry and railway industry. i.e. steel castings, steel forgings and
machined parts. In response to rising demand for high quality components for the automotive
industry, the company is investing in advanced machining centers and heat treatment
facilities.
Production flexibility and management skill, short lead time, technological knowledge,
quality management systems and experience in cooperation through license and know-
how agreements are their strengths.
Green sand and no bake casting technology, close die forging technology, high speed
machining technology and machining through cad cam technology, heat treatment technology,
in addition to that finally heavy duty brake manufacturing technologies are being engaged in
Cimsatas.
Over the years, Çimsataş invested heavily and kept working with utmost devotion to
maintain the highest quality assurance standards available. The company is awarded with ISO
9001 Quality System Certificate and ISO/TS 16949 Quality Management System
Certificate given by BVQI (Bureau Veritas Quality International). In addition to that the
company continued to improve employees standard and received the certificate of OHSAS
18001 Occupational Health and Safety Assessment Series. Cimsatas is awarded with ISO
14001 Enviromental Management Certificate. Beyond this, Çimsataş strives to ensure that its
quality policies and principles are in full compliance with all international regulations and
standards.
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The plant is based in Mersin by the coast of the Mediterranean, which has largest port in south
of Turkey.
The company has 4 main department as Machining, Foundry, Forging, Heat-Treatmant.
Figure-1
INTRODUCTION
Mechanical Engineering is the most comprehensive one of all engineering
professions.A mechanical engineering internship is the best option to acquire hands-on
experience after graduation, or even during your course work. in today's conditions
experience is very essential to employers when hiring candidate employees, so it often
becomes a standart for chosen as an engineer. Summer practices provides good opportunities
to make students see the application areas of the theoretical knowledge in industry.
The aim of this summer practice is to be informed of various types of manufacturing
processes for example machining, casting, forging, heat treatment, and etc.
I have completed my summer practice in ÇİMSATAŞ. I have been there for four weeks
from 24/08/2012 till 21/09/2012. During this time I had chance to observe machining with
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different kind of lathe and milling machine, modeling, sand casting, mechanical sand
reclamation, CAM, CAD, and simulation programs, grinding, mechanical presses, crack
control, tav-temper machines, cementation, tension test, toughness test etc. I also learn how to
use different types of measuring tools. Additionally, I could see how employers work and how
the company run by managers and engineers.
FORGING DEPARTMENT
Figure-2
Forging is a manufacturing process involving the shaping of metal using localized
compressive forces. Forging is often classified according to the temperature at which it is
performed: "cold", "warm", or "hot" forging. Forged parts can range in weight from less than
a kilogram to 580 metric tons. Forged parts usually require further processing to achieve a
finished part.
In modern times, industrial forging is done either with presses or with hammers
powered by compressed air, electricity, hydraulics or steam. These hammers may have
reciprocating weights in the thousands of pounds. Smaller power hammers, 500 lb (230 kg) or
less reciprocating weight, and hydraulic presses are common in art smithies as well. Some
8. 8
steam hammers remain in use, but they became obsolete with the availability of the other,
more convenient, power sources.
Forging can produce a piece that is stronger than an equivalent cast or machined part.
As the metal is shaped dur ing the forging process, its internal grain deforms to follow the
general shape of the part. As a result, the grain is continuous throughout the part, giving rise
to a piece with improved strength characteristics.
Some metals may be forged cold, but iron and steel are almost always hot forged. Hot
forging prevents the work hardening that would result from cold forging, which would
increase the difficulty of performing secondary machining operations on the piece. Also,
while work hardening may be desirable in some circumstances, other methods of hardening
the piece, such as heat treating, are generally more economical and more controllable.
There are many different kinds of forging processes available, however they can be grouped
into three main classes:
Drawn out: length increases, cross-section decreases
Upset: length decreases, cross-section increases
Squeezed in closed compression dies: produces multidirectional flow
Common forging processes include: roll forging, swaging, cogging, open-die forging,
impression-die forging, press forging, automatic hot forging and upsetting.
1. Forging Process
1.1. Drop Forging
Drop forging is a metal shaping process, the metal to be formed is first heated then shaped by
forcing it into the contours of a die, this force can be in excess of 2000 tons. The drop forging
process can be performed with the material at various temperatures;
Hot Forging
During hot forging the metals are heated to above their recrystallization temperature.
The main benefit of this hot forging is that work hardening is prevented due to the
recrystallization of the metal as it begins to cool.
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Cold Forging
Cold Forging is generally performed with metal at room temperature below the the
recrystallization temperature. Cold forging typically work hardens the metal.
There are two types of drop forging, open die and closed die.
Open die drop forging requires the operator to position the work piece while it is impacted by
the ram. The die attached to the ram is usually flat or of a simple contour, most of the shaping
is achieved by the operator physically positioning the work piece before each stroke of the
ram. There are also special dies which can be used to cut the metal, form holes or notches.
Figure-3
1.2. Press Forging
In forging, a mechanical forging press can also be used. A mechanical forging press stores
energy in a motor-driven flywheel. This energy drives a ram through another mechanical
device, most often a crank. The ram is significantly lighter than the hammer used in other
applications.
The ram used in a mechanical forging press is slower than a hammer and manipulates the
metal by squeezing it. Mechanical forging presses may have a force as large as 12,000
tons. Although the mechanical forging press is huge, it cannot forge as complicated or
large pieces as the hammers can.
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Press forging achieves more uniform internal structure due to
transmitting deformation to the interior layers of the worpiece. This effect is particularly
important when large shafts or other thick parts are forged.
Another form of forging press is the hydraulic forging press. These presses use high-
pressure fluid and are slower than hammers by a factor of about 100. The hydraulic
forging press is used for complex die forging. Presses with a force of 50,000 tons are used
for forging large airplane parts. There are also larger hydraulic presses with a force of
78,000 tons available.
,
Figure-4
1.3. Upset Forging
Performed on bar stock, upset forging decreases the length of the stock and increases its
cross-section. High pressures deform the metal and force material into a designated area of
the bar. The material is shaped into tools such as bolts, pinions, drill rods, and other objects
where high strength is a necessity. Upset forging refines the mechanical properties by re-
orienting the grain flow to the shape of the tool. The result is a component which is inherently
stronger than that which has been cast, welded, or machined.
The act of upset forging breaks up the cast structure of the material, aligns the grain flow,
and eliminates weaknesses in the material, such as microshrinkage, gas porosity, and areas of
low density. Rods, pinions, bolts, and other components created through upset forging exhibit
better levels of strength and soundness. Upset forged components resist deformation and
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breakage during use. These characteristics make them ideal for applications where high
performance is a must.
Figure-5
1.4. Roll forging
Roll forging is a process where round or flat bar stock is reduced in thickness and
increased in length. Roll forging is performed using two cylindrical or semi-cylindrical rolls,
each containing one or more shaped grooves. A heated bar is inserted into the rolls and when
it hits a stop the rolls rotate and the bar is progressively shaped as it is rolled through the
machine. The piece is then transferred to the next set of grooves or turned around and
reinserted into the same grooves. This continues until the desired shape and size is achieved.
The advantage of this process is there is no flash and it imparts a favorable grain structure
into the work-piece.
Figure-6
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2. How Does Forging Department Work at ÇİMSATAŞ
Figure-7
ÇİMSATAŞ is only use mechanical press forging to produce work-pieces. High quality
steel forgings are manufactured on production lines composed of induction billet heaters,
mechanical and hydraulic presses. Forge Shop production capacity is 20.000 tons per year.
There are 3 main department in the forging department at ÇİMSATAŞ. Those are die
design, die machining and press.
2.1. Die Design Department
Design department responsible to evaluate proficiencies of the offers which is brought
to company from customers. They start with decide to if they can be capable of realize the
offer with benefit. They calculate the total job time, material costs, worker fee etc. and
they propose their counter-offer. If the customer agreed about the proposal, design
Department will draw the work-pieces’ die on Auto-CAD after that the work-piece
designed by using Catia. Finally, they simulate their die by using simulation programme
which is called Deform-3D to see if there is any failure or crack with the die. If everything
is decent, drawings send to the die making Department.
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2.2. Die Machining Department
All of the dies which is used for forging operations are hard work steels. Die materials are
different from each other according to the work-pieces dimensions and presses which is going
to use when forging.
Ignot materials are processed to dies on Universal or CNC lathe machine and milling
machine. Dies are basically classified as pre-shape and finish. After dies get smoothed and
assembled they send to the presses according to weekly forging schedule.
Figure-8
2.3. Press Department
Figure-9
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When dies are completed at die machining Department dies are sent to the press
Department. Dies are get placed in a press machine and heat them up to 200-250 ˚C to avoid
cracks and failures.
There are 4 different product lines at ÇİMSATAŞ. Those are 1600TP-2500TP and two
of 4500TP. Each of the product line has trimming press by its own. Shear force that is needed
at trim press is less than forging press therefore trim presses are smaller than the other presses
in Figure-8 you can find the tonnage of the presses below. With the induction heater, which is
in each of the production lines, ingots are heated approximately up to 1200 ˚C. Heated ingots
are get formed by the closed dies which is assembled to mechanical presses. Finally, work-
pieces’ burrs cleaned by trimming presses.
After Pressing process, work-pieces are waited until it gets cool down. Eventually,
work-pieces are grinding according to the customers will.
Presses Tonnage Trimming Tonnage
1600 TP 320 TP
2500 TP 400 TP
1st 4500 TP 500 TP
2nd 4500 TP 630 TP
Figure-10
15. 15
2.4. Some of Work-Pieces Which is Forged in Forging Department
Figure-11
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FOUNDRY DEPARTMENT
Figure-13
Sand casting, also known as sand molded casting, is a metal casting process characterized by
using sand as the mold material. The term "sand casting" can also refer to an object produced via
the sand casting process. Sand castings are produced in specialized factories called foundries. Over
70% of all metal castings are produced via a sand casting process.
Sand casting is relatively cheap and sufficiently refractory even for steel foundry use. In addition to
the sand, a suitable bonding agent (usually clay) is mixed or occurs with the sand. The mixture is
moistened, typically with water, but sometimes with other substances, to develop strength and
plasticity of the clay and to make the aggregate suitable for molding. The sand is typically
contained in a system of frames or mold boxes known a flask. The mold cavities and gate
system are created by compacting the sand around models, or patterns, or carved directly into the
sand.
Steel and nodular ıron casting facility is equipped with induction melting furnaces,
moulding sand preperation system,automotic moulding lines, resin bonded sand molding line,core
making
lines and heat treatment. Foundry production capacity is 10.000 tons per year at ÇİMSATAŞ.
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1. Basic Processes
There are six steps in this processes.
Mold-making - The first step in the sand casting process is to create the mold for the casting.
In an expendable mold process, this step must be performed for each casting. A sand mold is
formed by packing sand into each half of the mold. The sand is packed around the pattern,
which is a replica of the external shape of the casting. When the pattern is removed, the
cavity that will form the casting remains. Any internal features of the casting that cannot be
formed by the pattern are formed by separate cores which are made of sand prior to the
formation of the mold. Further details on mold-making will be described in the next section.
The mold-making time includes positioning the pattern, packing the sand, and removing the
pattern. The mold-making time is affected by the size of the part, the number of cores, and
the type of sand mold. If the mold type requires heating or baking time, the mold-making
time is substantially increased. Also, lubrication is often applied to the surfaces of the mold
cavity in order to facilitate removal of the casting. The use of a lubricant also improves the
flow the metal and can improve the surface finish of the casting. The lubricant that is used is
chosen based upon the sand and molten metal temperature.
Clamping - Once the mold has been made, it must be prepared for the molten metal to be
poured. The surface of the mold cavity is first lubricated to facilitate the removal of the
casting. Then, the cores are positioned and the mold halves are closed and securely clamped
together. It is essential that the mold halves remain securely closed to prevent the loss of any
material.
Pouring - The molten metal is maintained at a set temperature in a furnace. After the mold
has been clamped, the molten metal can be ladled from its holding container in the furnace
and poured into the mold. The pouring can be performed manually or by an automated
machine. Enough molten metal must be poured to fill the entire cavity and all channels in
the mold. The filling time is very short in order to prevent early solidification of any one
part of the metal.
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At ÇİMSATAŞ the molten metal is followed by a form which is called “Ergitme Takip Formu”
with this document which material has been added to the molten metal, what is it going to use for,
temperature measurements, are known and registered. This form is given in Appendix B.
Cooling - The molten metal that is poured into the mold will begin to cool and solidify once
it enters the cavity. When the entire cavity is filled and the molten metal solidifies, the final
shape of the casting is formed. The mold can not be opened until the cooling time has
elapsed. The desired cooling time can be estimated based upon the wall thickness of the
casting and the temperature of the metal. Most of the possible defects that can occur are a
result of the solidification process. If some of the molten metal cools too quickly, the part
may exhibit shrinkage, cracks, or incomplete sections. Preventative measures can be taken
in designing both the part and the mold and will be explored in later sections.
Removal - After the predetermined solidification time has passed, the sand mold can simply
be broken, and the casting removed. This step, sometimes called shakeout, is typically
performed by a vibrating machine that shakes the sand and casting out of the flask. Once
removed, the casting will likely have some sand and oxide layers adhered to the surface.
Shot blasting is sometimes used to remove any remaining sand, especially from internal
surfaces, and reduce the surface roughness.
Trimming - During cooling, the material from the channels in the mold solidifies attached to
the part. This excess material must be trimmed from the casting either manually via cutting
or sawing, or using a trimming press. The time required to trim the excess material can be
estimated from the size of the casting's envelope. A larger casting will require a longer
trimming time. The scrap material that results from this trimming is either discarded or
reused in the sand casting process. However, the scrap material may need to be
reconditioned to the proper chemical composition before it can be combined with non-
recycled metal and reused.
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Figure-14
2. Pattern Making
The making of patterns, called patternmaking (sometimes styled pattern-making or pattern
making), is a skilled trade that is related to the trades oftool and die making and moldmaking, but
also often incorporates elements of fine woodworking. Patternmakers (sometimes styled pattern-
makers orpattern makers) learn their skills through apprenticeships and trade schools over many
years of experience. Although an engineer may help to design the pattern, it is usually a
patternmaker who executes the design.
2.1. Parts of the Pattern
Figure-15
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The cavity in the sand is formed by using a pattern (an approximate duplicate of the real part),
which are typically made out of wood, sometimes metal. The cavity is contained in an aggregate
housed in a box called the flask. Core is a sand shape inserted into the mold to produce the internal
features of the part such as holes or internal passages. Cores are placed in the cavity to form holes
of the desired shapes. Core print is the region added to the pattern, core, or mold that is used to
locate and support the core within the mold. A riser is an extra void created in the mold to contain
excessive molten material. The purpose of this is feed the molten metal to the mold cavity as the
molten metal solidifies and shrinks, and thereby prevents voids in the main casting.
Figure-16
In a two-part mold, which is typical of sand castings, the upper half, including the top half of
the pattern, flask, and core is called cope and the lower half is called drag. The parting line or the
parting surface is line or surface that separates the cope and drag. The drag is first filled partially
with sand, and the core print, the cores, and the gating system are placed near the parting line. The
cope is then assembled to the drag, and the sand is poured on the cope half, covering the pattern,
core and the gating system. The sand is compacted by vibration and mechanical means. Next, the
cope is removed from the drag, and the pattern is carefully removed. The object is to remove the
pattern without breaking the mold cavity. This is facilitated by designing a draft, a slight angular
offset from the vertical to the vertical surfaces of the pattern. This is usually a minimum of 1° or 1.5
mm (0.060 in), whichever is greater. The rougher the surface of the pattern, the more the draft to be
provided.
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2.2. Terms
Pattern – an exact replica of the object you want to cast. It is made of an easy to work
material (often wood). The pattern is used to make molds for casting.
Pouring Cup – basically a funnel that provides an easy target for the metal to be poured into
the mold.
Sprue – a hole where the metal enters the mold. It is ideally tapered to prevent air from
entering the casting.
Well – forms a cushion for the metal pouring through the sprue so the sand is not washed
into the casting (see the diagram under “Rules for Gating.”
Runner – a channel for the metal to get to the negative space left by the pattern.
Riser – as the casting cools it will shrink. Because the riser is larger, it will cool slower and
feed liquid metal to the shrinking casting, thus preventing a number of defects.
Gate – the place or places where the metal enters the casting.
Skim Bob – a small hollow above the runner that acts to skim off floating dross, sand and
debris so it does not enter the casting.
Flask – a box that contains the mold. Usually it is composed of two parts like two picture
frames that fit together.
MACHINING DEPARTMENT
Figure-17
Machining is any of various processes in which a piece of raw material is cut into a
desired final shape and size by a controlled material-removal process. The main job of
machining department is facing, drilling, boring, parting, turning, peripheral milling, face
milling processes on work-pieces according to customers’ demands. Work-pieces may come
23. 23
either from foundry or forging departments. Then it comes to machining department. This
department is the final step for almost all work-pieces. Machine shop is equipped with high-
tech CNC and conventional machine tools. According to customer demand forged and casted
parts are machined and delivered as finished components.
There are five types of machines in machining department at ÇİMSATAŞ. Those are
lathes, milling machines, drilling machines, and grinding machines. Majority of the lathes in
machining department is twin turret lathes and also they mostly have twin palette milling
machines.
1. Machining on a Lathe
A lathe is a machine tool which rotates the work-piece on its axis to perform various
operations such as cutting, knurling, drilling, or deformation with tools that are applied to the
work-piece to create an object which has symmetry about an axis of rotation.
Universal Lathe Machines: The most useful and easy one, it is very appropriate for
non-serial operations. The lathe is switched on and the chuck is rotated. And since the
table which fixed the byte can be moved in the vertical direction, and the right-and-left
direction by operating some handles.
.
Figure-18 Figure-19
CNC Lathe Machines: CNC stands for “Computer Numerical Control”. The computer
loaded with the needed software and picture leads the operation. It is very appropriate
for serial operations and they are programmed with G and M codes. t makes all the
24. 24
required operations by itself. Once it is adjusted and calibrated, it repeats the same
processes on identical parts.
Vertical Lathe Machines: It is used to operate on the very heavy parts. These parts
rotate around a vertical pressure better than the others.
Figure-20
1.1. Facing
Facing is usually the first and an essential process on a machining centre, using a face-
milling cutter, on any work-piece, because many a time, the work-piece is obtained through a
“rough” casting process. The advantage of a cast part is that a work-piece with slightly
oversize dimensions is made available, usually requiring very little machining. Facing is the
process of removing metal from the end of a work-piece to produce a flat surface. Most often,
the work-piece is cylindrical, but using a four-jaw chuck you can face rectangular or odd-
shaped work to form cubes and other non-cylindrical shapes. And also by using vise any
shape of work-pieces can be processed.
1.2. Drilling
The tailstock of a lathe can be used for drilling, with the aid of a drill chuck attachment.
The drill chuck has a morse taper shaft which can be push into the shaft of the tailstock,
locking it in position.
25. 25
The usual starting point for drilling with a center lathe is to use a countersink bit. This is
used to drill slightly into the material and creates a starting point for other drills that are going
to be used. Attempting to drill with a traditional drill bit without countersinking first will lead
to the drill bit slipping straight away. It is not possible to drill a hole successfully or safely
with out using a center drill first.
If a large diameter hole is needed then a small hole is drilled first (eg. 4mm dia). Then the
hole is enlarged approximately 2mm at a time. Trying to drill a large diameter hole in one go
will inevitably lead to the drill bit over heating and then jamming in the material. This is
potentially dangerous.
When drilling, it is very important to use soluble oil as a coolant. This should be
constantly fed onto the drill bit to keep it cool. This will help prevent jamming and over-
heating. Over-heating will blunt the drill bit quickly.
Figure-21
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1.3. Boring
Boring on a lathe, like boring on a mill, is defined as the enlarging of a existing hole. This
hole can either be drilled, cast, forged, or molded.. As with mill boring the need is usually
based upon tolerance and/or finish requirements.
Most boring is accomplished with a boring bar mounted in the tool post.
Mounting the holder and boring tool bar with cutter bit on the tool post and revolving the
work-piece.
Mounting the work-piece in a fixed position to the carriage and revolving the boring tool
bar and cutter bit in a chuck attached to the headstock spindle. (This is a special process
and not used in most machine shops).
Boring is necessary in many cases to produce accurate holes. Drilled holes are seldom
straight due to imperfections in the material which cause drills to move out of alignment.
Therefore, where accuracy is important, drilled holes are usually made undersize and then
bored or reamed to the proper dimensions. Boring is also useful in truing large holes in
flat material.
Figure-22
1.4. Parting
Parting uses a blade-like cutting tool plunged directly into the work-piece to cut off the
work-piece at a specific length. It is normally used to remove the finished end of a work-piece
from the bar stock that is clamped in the chuck. Other uses include things such as cutting the
head off a bolt.
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A parting tool is deeper and narrower than a turning tool. It is designed for making narrow
grooves and for cutting off parts. When a parting tool is installed, ensure that it hangs over the
tool holder enough that the the holder will clear the work-piece.
With the tip of the tool just beyond the surface of the work-piece, turn on the lathe. Slowly
advance the cross-slide crank until the tool starts cutting into the metal. Keep advancing the
tool until you get a steady chip curling off the work-piece and then try to maintain this cutting
speed.
1.5. Turning
Turning is one of the most common of metal cutting operations. In turning, a work-piece
is rotated about its axis as single-point cutting tools are fed into it, shearing away unwanted
material and creating the desired part. Turning can occur on both external and internal
surfaces to produce an axially-symmetrical contoured part.
Turning is the removal of metal from the outer diameter of a rotating cylindrical work-
piece. Turning is used to reduce the diameter of the work-piece, usually to a specified
dimension, and to produce a smooth finish on the metal. Often the work-piece will be turned
so that adjacent sections have different diameters
Figure-23
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1.6. Some of Work-Pieces Which is Processed in Machining Department
Figure-24
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2. Machining on a Milling Machine
A milling machine is a machine tool used to machine solid materials. Milling machines are
often classed in two basic forms, horizontal and vertical, which refers to the orientation of the
main spindle. Milling machines can perform a vast number of operations, from simple (e.g.,
slot and keyway cutting, planning, drilling). Cutting fluid is often pumped to the cutting site
to cool and lubricate the cut and to wash away the resulting swarf. Milling is well suited and
widely used for mass production. In all cases a multiple-tooth cutter used so that metal
removal rate is high. Unquestionably, milling, than any other machining processes, produces
more flat surfaces.
Since milling provides rapid metal removal and also can produce a very good surface
finish, it is one of the most important machining processes. It is widely used for general
purpose machining in job-shops and also for tool die work.
Milling operations can be classified into three main categories:
Peripheral Milling
Face Milling
End Milling
Peripheral Milling: In peripheral (or slab) milling, the milled surface is generated by teeth
located on the periphery of the cutter body. The axis of cutter rotation is generally in a
plane parallel to the work-piece surface to be machined.
Face Milling: In face milling, the cutter is mounted on a spindle having an axis of rotation
perpendicular to the work-piece surface. The milled surface results from the action of
cutting edges located on the periphery and face of the cutter.
End Milling: The cutter in end milling generally rotates on an axis vertical to the work-
piece. It can be tilted to machine tapered surfaces. Cutting teeth are located on both the
end face of the cutter and the periphery of the cutter body.
Milling machines has two different methods to process. One of them called up milling
is also referred to as conventional milling. The direction of the cutter rotation opposes the
feed motion. For example, if the cutter rotates clockwise , the work-piece is fed to the right in
31. 31
up milling. On the other hand, second method which is down milling is also referred to as
climb milling. The direction of cutter rotation is same as the feed motion. For example, if the
cutter rotates counterclockwise , the work-piece is fed to the right in down milling.
2.1. Parts of the Milling Machine
1. Face Milling Cutter
2. Spindle
3. Spindle Head
4. Column
5. Table
6. Saddle
7. Knee
8. Base
9. Spindle Switch
10. Spindle Speed Gear Lever
11. Spindle Speed Control Lever
12. Oil Tank
13. Table Manual Wheel
14. Table Lock Bar
15. Saddle Automatic Moving Bar
16. Saddle Automatic Moving
Control Dial
17. Saddle Manual Wheel
18. Knee Manual Wheel
19. Quick Button
Figure-26
32. 32
3. Differences Between Milling Machine and Lathe
Lathes and milling machines are both used for cutting raw material, but they have very
different ways of doing so. Lathes spin the material, whereas a milling machine uses a
spinning tool for various cutting operations. To utilize either, you must know the differences
between the two and what each is capable of.
Lathes create cylindrical parts using outside and inside diameter cutting tools of
varying sizes and shapes. The material spins on a chuck while a tool cuts away material. The
tool is secured on the tool post or in the tail stock.
A milling machine spins the tool to cut material that is held stationary in a fixture or a vise.
Milling machines use cylindrical cutting tools, such as end mills and drills, to remove
material to make a finished part.
Setting up a lathe involves less precision, as the chuck itself will center the part for
cutting. When installing the chuck jaws, make sure they are equidistant from the center. This
will prevent any errors during the cutting.
To use a milling machine, you must measure the vise or fixture to make sure it is straight. To
do so, use a dial indicator on the spindle and tap the vise until it is perfectly straight.
Retighten the retention bolts and recheck for straightness, making whatever adjustments are
necessary.
4. Some Machines and Their Technical Specifications at ÇİMSATAŞ
OKUMA LR-15
Twin turret
Swing over bed 450 mm
Swing over carriage 300 mm
Swing over cross slide 250 mm
Max. turning dia/lenght 240/600 mm
Subspindle
Bartec bar feeder
Conveyer
Figure-27
33. 33
OKUMA LR-15 M
Chuck size 8 inch
Max. swing 17,71 inch
Max. turning dia 10,62 inch
X-Y-Z axis travel 6,880/12,6/5,11
inches
Rapid traverse (X/Z) 591/787 IPM
Spinsle bore 2,440
Spindle speeds 4200 RPM
Spindle motor 10 HP
SQ shank dia. 1,0 inch Figure-28
RD shank dia 1,5 inch
Mazak FH-6000
CNC control Mazatrol Fusion 640 M
Stationary Single column construction
Max RPM 10000 40HP
2 Ranges, 1 Spindles, 2 Pallets
Max. 40 tools max. length/dia/weight
14,170/5,740/26
Tool change time 1,0
Table size L:19.690 X W:19.690
Max weight of the work-piece 2200 Figure-29
X-Y-Z axis travel 31.500 Inch - 31.500 Inch - 34.700 Inch (1575 IPM)
34. 34
HEAT TREATMENT DEPARTMENT
Figure-30
Heat Treatment processes are very important and essential for automotive, railway and
construction machinery parts.Parts are heat treated with different applications such as
normalizing, carburizing and induction hardening, water/oil quenching, tempering, isothermal
annealing.
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. Heat
treatment techniques include annealing, case hardening, precipitation
strengthening, tempering 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.
35. 35
There is a Phase diagram of an iron-carbon alloying system in Appendix C.
1. Heat Treatment Processes at ÇİMSATAŞ
1.1. Normalizing
Normalizing imparts both hardness and strength to iron and steel components. In addition,
normalizing helps reduce internal stresses (Fig. 1) induced by such operations as forging, casting,
machining, forming or welding. Normalizing also improves microstructural homogeneity and
response to heat treatment (e.g. annealing or hardening) and enhances stability by imparting a
“thermal memory” for subsequent lower-temperature processes. Parts that require maximum
toughness and those subjected to impact are often normalized
Figure-31
Normalizing is typically performed in order to:
Improve machinability
Improve dimensional stability
Modify and/or refine the grain structure
Produce a homogeneous microstructure
Reduce banding
36. 36
Improve ductility
Provide a more consistent response when hardening or case hardening
By way of example, many gear blanks are normalized prior to machining so that during
subsequent hardening or case hardening dimensional changes such as growth, shrinkage or warpage
will be better controlled.
Soak periods for normalizing are typically one hour per inch of cross-sectional area but not less
than two hours at temperature. It is important to remember that the mass of the part or the workload
can have a significant influence on the cooling rate and thus on the resulting microstructure. Thin
pieces cool faster and are harder after normalizing than thicker ones. By contrast, after furnace
cooling in an annealing process, the hardness of the thin and thicker sections are about the same.
Low-carbon steels typically do not require normalizing. If these steels are normalized, however,
no harmful effects result. Castings with relatively uniform wall thickness and section sizes are
usually annealed rather than normalized. Other castings, especially those having a complex shape or
interconnected thick and thin sections and are thus prone to high levels of residual stresses, benefit
from normalizing. The microstructure obtained by normalizing depends on the composition of the
castings (which dictates its hardenability) and the cooling rate.
1.2. Annealing
Figure-32
37. 37
Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered,
causing changes in its properties such as hardness and ductility. It is a process that produces
conditions by heating to above the critical temperature, maintaining a suitable temperature, and then
cooling. Annealing is used to induce ductility, soften material, relieve internal stresses, refine the
structure by making it homogeneous, and improve cold working properties.
In the cases of copper, steel, silver, and brass, this process is performed by substantially heating
the material (generally until glowing) for a while and allowing it to cool. Unlike ferrous metals—
which must be cooled slowly to anneal—copper, silver and brass can be cooled slowly in air or
quickly by quenching in water. In this fashion the metal is softened and prepared for further work
such as shaping, stamping, or forming.
There are three stages in the annealing process: recovery, recrystalization, and grain growth.
The first stage is recovery, and it results in softening of the metal through removal of crystal defects
(the primary type of which is the linear defect called a dislocation) and the internal stresses which
they cause. The recovery stage covers all annealing phenomena that occur before the appearance of
new strain-free grains. The second stage is recrystallization, where new strain-free grains nucleate
and grow to replace those deformed by internal stresses.If annealing is allowed to continue once
recrystallization has been completed, then grain growth (the third stage) occurs. In grain growth, the
microstructure starts to coarsen and may cause the metal to have less than satisfactory mechanical
properties.
1.3. Tempering
Figure-33
38. 38
Tempering is a process of heat treating, which is used to increase the toughness of iron-
based alloys. It is also a technique used to increase the toughness of glass. For metals, tempering is
usually performed after hardening, to reduce some of the excess hardness, and is done by heating
the metal to a much lower temperature than was used for hardening. The exact temperature
determines the amount of hardness removed, and depends on both the specific composition of the
alloy and on the desired properties in the finished product. For instance, very hard tools are often
tempered at low temperatures, while springs are tempered to much higher temperatures. In glass,
tempering is performed by heating the glass and then quickly cooling the surface, increasing the
toughness.
Tempering is a heat treatment technique applied to ferrous alloys, such as steel or cast iron, to
achieve greater toughness by decreasing the hardnessof the alloy. The reduction in hardness is
usually accompanied by an increase in ductility, thereby decreasing the brittleness of the metal.
Tempering is usually performed after quenching, which is rapid cooling of the metal to put it in its
hardest state. Tempering is accomplished by controlled heating of the quenched work-piece to a
temperature below its "lower critical temperature". This is also called the lower transformation
temperature or lower arrest (A1) temperature; the temperature at which the crystalline phases of the
alloy, called ferrite and cementite, begin combining to form a single-phase solid solution referred to
as austenite. Heating above this temperature is avoided, so as not to destroy the very-hard,
quenched microstructure, calledmartensite.
Figure-34
39. 39
Precise control of time and temperature during the tempering process is critical to achieve
the desired balance of physical properties. Low tempering temperatures may only relieve some of
the internal stresses, decreasing brittleness while maintaining a majority of the hardness. Higher
tempering temperatures tend to produce a greater reduction in the hardness, sacrificing some yield
strength and tensile strength for an increase in elasticity andplasticity. However, in some low alloy
steels, containing other elements like chromium and molybdenum, tempering at low temperatures
may produce an increase in hardness, while at higher temperatures the hardness will decrease. Many
steels with high concentrations of these alloying elements behave like precipitation hardening
alloys, which produce the opposite effects under the conditions found in quenching and tempering,
and are referred to a maraging steels.
In carbon steels, tempering alters the size and distribution of carbides in the martensite,
forming a microstructure called "tempered martensite". Tempering is also performed
on normalized steels and cast irons, to increase ductility, machinability, and impact strength. Steel
is usually tempered evenly, called "through tempering," producing a nearly uniform hardness, but it
is somethimes heated unevenly, referred to as "differential tempering," producing a variation in
hardness. In tempered glass, tempering is accomplished by creating internal stresses in
the amorphous structure, to increase both impact resistance and safety in the event of breakage.
1.4. Cementation
The cementation process is an obsolete technique for making steel by carburization of iron.
Unlike modern steelmaking, it increased the amount ofcarbon in the iron. It was apparently
developed before the 17th century. Derwentcote Steel Furnace, built in 1720, is the earliest
surviving example of a cementation furnace. Another example in the UK is the Cementation
furnace in Doncaster Street, Sheffield.
The process begins with wrought iron and charcoal. It uses one or more long
stone pots inside a furnace. Typically, in Sheffield, each was 14 feet by 4 feet and 3.5 feet deep.
Iron bars and charcoal are packed in alternating layers, with a top layer of charcoal and then
refractory matter to make the pot or "coffin" airtight. Some manufacturers used a mix of powdered
charcoal, soot and mineral salts, called cement powder. In larger works up to 16 tons of iron was
treated in each cycle.
Depending on the thickness of the iron bars, the pots were then heated from below for a week or
more. Bars were regularly examined and when the correct condition was reached the heat was
withdrawn and the pots were left until cool—usually around fourteen days. The iron had "gained" a
40. 40
little over 1% in mass from the carbon in the charcoal, and had become heterogeneous bars
of blister steel.
The bars were then shortened, bound, heated and hammered, pressed or rolled to become shear
steel. Alternatively they could be broken up and melted in a crucible using a crucible furnace with
a flux to become crucible steel or cast steel, a process devised by Benjamin Huntsman in the 1740s.
1.5. Induction Hardening
Figure-35
The most common applications are induction hardening of steel parts,
induction soldering/brazing as a means of joining metal components and induction annealing to
selectively soften an area of a steel part.
Induction heating is a non contact heating process which utilises the principle
of electromagnetic induction to produce heat inside the surface layer of a work-piece. By placing
a conductivematerial into a strong alternating magnetic field, electrical current can be made to flow
in the material thereby creating heat due to the I2R losses in the material. In magnetic materials,
further heat is generated below the curie point due to hysteresis losses. The current generated flows
predominantly in the surface layer, the depth of this layer being dictated by the frequency of the
alternating field, the surface power density, the permeability of the material, the heat time and the
diameter of the bar or material thickness. By quenching this heated layer in water, oil or
a polymer based quench the surface layer is altered to form a martensitic structure which is harder
than the base metal.
41. 41
Induction heating can produce high power densities which allow short interaction times to reach
the required temperature. This gives tight control of the heating pattern with the pattern following
the applied magnetic field quite closely and allows reduced thermal distortion and damage.
This ability can be used in hardening to produce parts with varying properties. The most
common hardening process is to produce a localised surface hardening of an area that needs wear-
resistance, while retaining the toughness of the original structure as needed elsewhere. The depth of
induction hardened patterns can be controlled through choice of induction-frequency, power-density
and interaction time.
Limits to the flexibility of the process arise from the need to produce dedicated inductors for
many applications. This is quite expensive and requires the marshalling of high current densities in
small copper inductors, which can require specialized engineering and 'copper-fitting'.
CONCLUSION
I spend twenty days in different departments at ÇİMSATAŞ. I had chance to see almost
everything about manufacturing and processing because ÇİMSATAŞ is one of the best and well
known company in Turkey on their sector. I had a big chance when I was doing my summer
practice at ÇİMSATAŞ because ÇİMSATAŞ is an integrated factory which is a few in Turkey.
In my opinion, practical knowledge and experience is way important than theoretical
knowledge and I am glad to had this experience in a factory. In every department I learned different
processes and had chance to examine machines and products. It was really important that, to find
answers to those questions which is “How does it work ?”, “How could it be machined this work-
piece ?” , “What is the material of this and why that material is more suitable for that?”.
The biggest benefit of this summer practice is to see how a factory or organization is
running. I was lucky to choose this company because there way totaly 42 engineers at ÇİMSATAŞ.
That’s why I observe every one of engineer and try to understand how they organize workers, how
they approach the cases and try to solve it. I realize that the most important role belongs to
Mechanical Engineers. In every stage, planning of production, adjusting the machines, arranging
the operations ad preparing the operation page that means almost everything in production,
determining the machine tools, time etude of operations, jobshop investments are the duties of the
office engineers.
In conclusion, that was absolutely most progressive experience in my life. When my
Professional life begins I will always remember and use the knowledge and experience that I gain
with this summer practice.
