UNIVERSITY OF GAZİANTEP

FACULTY OF ENGINEERING

DEPARTMENT OF MECHANICAL ENGINEERING

ME 299

ENGINEERING PRACTICE PROGRAMME

NAME:Mustafa

SURNAME:Cigal

NUMEBER:200961089

ABOUT ÇILTUĞ

Çiltuğ was established on May 15th, 1971 in Gaziantep as a collective company and

became a joint stock company as of April 1st, 1976. Development and modernization

procedures of the company were completed in 1977, developed and became group of

companies since 1980.

Our Heavy Machinery and Steel Structure factory established on 10,000 sqm.

Covered area and 7,000 sqm. outdoor area

Our Wind Tower and Accessories Construction factory is established on 5,000 sqm.

Covered area 32,000 sqm. outdoor area

Both of these workshops are located across the road from each those are within the 1st

Industrial Zone of Gaziantep city in South-East of Turkey where 220km away from

Iskenderun Sea port and 280 km away from Mersin Seaport with conjunction of TEM

motorway.

All workshop fabrication and erection works are achieved by our well-experienced

technical personnel under the international Quality Management Systems ISO 9001:2008

certified by RWTÜV / TÜV CERT.

In addition to this standard, our technical team is equipped with EN ISO 3834-2 Fusion

Welding of Metallic Materials Management Quality Requirements System and qualified

with EN 1090-2 (DIN 18800-7) Technical requirements for the execution of steel

structures system. However, all procedures, preparations are going on for Health &

Safety Equipment Certifications with ISO 14001:2004&OHSAS 18001:2007. Both of

our workshop engineers are certified for the NDT Tests Level-2 under the EN473

Standards by independent and accredited authorities. All welders have test certificates

under the EN287 Standards.

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1.MAIN ACTIVITIES OF ÇILTUĞ

Hydro mechanical Equipments for Dam, Energy and Hydro Electrical Power Plants

such as:

• Penstocks, Radial and Stoplog Gates, Sliding Gates

• Butterfly Valves and Conical Valves

• Trashrack and Trashrack Cleaning Machines

Electro mechanical Equipments for Dam, Energy and Hydro Electrical Power Plants

such as:

• Spiral Case & Stay Rings

• Draft Tubes

• Pelton Distributors

• Kaplan Distributors and accessories

• Turbine Inlet pipes

• Turbine Housing

• Generator Stator Frames

Fabrication and Erection of Wind Towers up to 100 meters,

Steel Constructions and Erection works for Thermal Power Plants and Petrochemical

Industries,

Turn-key Civil and Contracting Works,

Fabrication and Erection Works for Heavy Steel Structures such as Pressurized

Vessels,

Petroleum Storage Tanks,

Fabrication and Erection Works for Transport and Cement Industries

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INTRODUCTİON

I have done my summer practice in Çiltuğ Ağır Makine sanayi and in savcılı düküm. I

went çiltuğ ağır makine sanayi for 15 days and I went savcılı döküm for 5 days. I started

ME299 Engineering practice program on 2012 june 18th. and finished on 2012 july 10th.

The aim of this summer practice is to got used to the student to the work environment

and we imrove the relations with workers ,engeneers and etc. to convenience after

graduate.the other purposes are to see work life of engineers and observe engineers-workers

mowing with them and how they are approaching problems

Second Year Summer Practice Programme (ME 299) covers the following topics:

a. Foundry work

b. Welding and heat treatment

c. Chip removal processes such as turning, milling, drilling, grinding, etc.

d. Press work and hot/cold working processes

e. Special purpose machines and processes

I worked at the project of spiral case (picture 10) of francis dam. Schedule of this project is:

Spiral case

1Material Procurement

2 Approval of material certificates by Çiltuğ

3 Approval of welding procedures by customer

Stay ring Manufacturing

4 Plasma arc Cutting

5 Flange Segments Assembly and Welding

6 Flanges Machining

7 Vanes Machining (cnc borwering)

8 Checking of vanes with templates

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9 Assembly

10 Welding

11 Dimenional Control After Welding

12 Grinding And Cleaning

13 NDT Before Heat Treatment by Ciltug

14 NDT Before Heat Treatment by customer

15 Heat Treatment of Stay vanes + Stay Ring

16 NDT After Heat Treatment

Spiral Case Manufacturing

17 Cutting

18 Bending

19 Preassembly

SC Main Assembly

20Main Assembly

21 Main Welding

22 NDT after assembly by Ciltug

23 NDT after assembly by customer

24 Main Machining and Drilling

25 Dimensional Check

26 Hydrostatic test

27 Sandblasting and Painting

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28 Submission of Quality files

29 Packing and Shipment

SPİRAL CASE

In a hydroturbine, a housing designed to provide uniform water intake around the entire

circumference of the distributor, that is, to permit all the guide vanes to be held in an axially

symmetrical position. The cross section of a spiral case narrows at a constant rate

downstream. Hydroelectric power plants operating under heads greater than 50–60 m use steel

spiral cases with circular cross sections that shroud the stator almost completely. Spiral cases

(picture 1) used with lower heads are made of reinforced concrete; they shroud approximately

225° of the stator’s circumference, and their cross sections are T-shaped. Unlike other

hydroturbine settings, for example, open settings, spiral cases make it possible to locate a

major part of the turbine mechanism outside of the water, which improves the turbine’s

operating conditions.

1 MATERIAL PROCUREMENT

Project which sended by costumer ,examining. prepared a list of material which needed

fo project. required materials in the list supplied(plate, nut, seal, screw,washer,threaded rod…

2 APPROVAL OF MATERİAL CERTİFİCATES BY COSTUMER

Materials standards are checked.

3 APPROVAL OF WELDİNG PROCEDURES BY COSTUMER

Welding type is selected according to the standards

STAY RING MANUFACTURİNG

Stay ring (picture 2).

4 PLASMA ARC CUTTING

We entered the dimension of stay ring to plasma arc cutting (picture 3). And sheet was cut.

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4.1 Plasma cutting 

Plasma cutting is a process that is used to cut steel and other metals of different

thicknesses (or sometimes other materials) using a plasma torch. In this process, an inert gas

(in some units, compressed air) is blown at high speed out of a nozzle; at the same time an

electrical arc is formed through that gas from the nozzle to the surface being cut, turning some

of that gas to plasma. The plasma is sufficiently hot to melt the metal being cut and moves

sufficiently fast to blow molten metal away from the cut.

4.2 CNC cutting methods

CNC tables allow a computer to control the torch head producing clean sharp cuts.

Modern CNC plasma equipment is capable of multi-axis cutting of thick material, allowing

opportunities for complex welding seams that are not possible otherwise. For thinner material,

plasma cutting is being progressively replaced bylaser cutting, due mainly to the laser cutter's

superior hole-cutting abilities.

A specialized use of CNC Plasma Cutters has been in the HVAC industry. Software

processes information on ductwork and creates flat patterns to be cut on the cutting table by

the plasma torch. This technology has enormously increased productivity within the industry

since its introduction in the early 1980s.

In recent years there has been even more development. Traditionally the machines'

cutting tables were horizontal, but now vertical CNC plasma cutting machines are available,

providing for a smaller footprint, increased flexibility, optimum safety and faster operation.

application of plasma cutting machine is as follow:

• auto sector – (chassis, cabins, etc…)

• auto motive fabrication

• ship building – (interior design contractors, ship contractors, etc…)

• railway – (vendor of railway)

• mining

• pharma & medical machinery6

• food processing machinery

• structure fabricators

• steel service center

• defense

• educational institutions

• earth moving (dumpers, buckets, etc…)

advantage of plasma technology:

• high cutting accuracy and contouring precision

• excellent dynamic properties

• high positioning speeds

• low vibration due to low profile design of machine and energy supply chain

• use of various processes and assemblies

• energy supply mounted on the floor

• working widths up to 6000 mm

• working lengths as per requirement

In addition we are also dealing in products like cnc plasma cutting machine, plasma

cutting machine, plasma metal cutting machine, plasma cnc cutting machine, air plasma

cutting machine, plasma arc cutting machine.

5 FLANGE SEGMENTS ASSEMBLY AND WELDING

we cut parts of flange segments with plasma arc cutting from plate . we cut 6 or 8 parts to

big flange, 3 or 4 parts to medium flange ,1 or 2 parts flange to small flange. Then this

parts combine each other and welded.

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6 FLANGE MACHINING

we turning the flanges to remove welding excess and to get right scale. And we drill

holes to screw assemmbly..

6.1 machining of metals

Machining is carried out to cut a metal part to a required shape and size. Machining

practices can have a profoun deffect on the grain structure , usefulness , and working life of a

metal part. This can be the result of distortion, notches produced by machining, and by the

disturbance of the surface while the metal is being cut. On the other hand, the composition

and cleanliness of the metal being cut is important indetermining the quality of cut and final

finish , as well as the life of the cutting machine tool.

The surface finish of a machined article determines the level of surface smoothness and

lack of notches and irregularities on the surface. In addition to the rake of the cutting tool , the

use of lubricants effects the surface finish. In the absence of the lubricants , pressure welding

of the chips is a problem , especially for softer metals such as aluminium and low carbon

steels. Pressure welding produces a built up edge which makes the surface of the part rough

and torn

6.1.1 Turning

Turning constituutes the majority of lathe work. The work usually is heldbetween

centers or in chuck, and right-hand tool is used. So that the cutting forces, resulting from

feeding the tool from right to left, tend to force the workpiece against the handstock and thus

provide better work support.

Lathes are designed solely for turning operations so that precise controll of the cutting

result in tight tolerances. The work piece is mounted on chuck, which rotates relative to the

stationary tool.

The term ‘facing’ is the producing of a flat surface as the result of the being fed across the

end of rotating workpiece as shown in 9 ang 10.facing is often used to prove the finish of

surfaces that have been parted.

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The term drilling on lathes is done with the drill held in tailstock quill and fed against a

workpiece that is rotated in chuck.

If one attempts to turn a long, slender piece between centers, the radial force exerted by

the cutting tool or the weight of the workpiece itself , may cause it to be deflected out of line.

Steady rests and follow rests, provide means for supporting such work between the headstock

and the tailstock. The steady rest is clamped to the lathe ways and three movable fingers that

are adjusted to contact the work and align it. A light cut should be taken before adjusting the

fingers to provide a smooth contact-surface area.

A steady ret also can be used in place of the tailstock as a means of the supporting the end

of long piecesi, pieces having too large an internal hole to permit using a regular dead center,

or work where the end must be open for boring. In such cases the handstock and of the work

must be held in chuck to prevent its moving longitudinally, and tool feed should be toward the

headstock.

A follow rest is bolted to the lathe carriage. It has two contact fingers that are adjusted to

bear against to workpieve , opposite the cutting tool, so as to prevent the work from deflected

away from cutting tool by the cutting force.

In çiltuğ there are lots of lathes in the materyal removal depermant. One of them is

vertical lathe (picture4) which have Ø4700/Ø8000mm-H2300mm Work Piece Dimensions.

6.1.2 Drilling

In manufacturing, it is probable that more holes are produced than any other shape; and

a large proportion of these are made by drilling. Consequently; drilling is a very important

process. Although drilling appears to be a relative simple process, certain aspects of it cause

considerable difficulty. Most drilling is done with a tool having two cutting edges. These

edges are at the end of a relatively flexible tool. Cutting action takes place inside the

workpiece. Friction results in heat that is additional to that due to chip formation. The counter

flow of the chip makes lubrication and cooling difficulties.

Most common type of drills are twist drills. These have three basic parts; body, point

and the shank. The body contains two or more spiral or helical grooves called flutes separated

by lands. A two fluted drill is the conventional type used for originating and drilling holes.

Some with either interior or external oil channels are used principally for enlarging holes

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previously made. Both have greater productivity and improved finish than two fluted drills.

Other drills with various flute angles are available to give improved drilling to special

materials and alloys.

7 VANES MACHINING (WITH CNC BORHWERG)

we processed vanes in cnc borhrweg (picture 5). we translate dimensiond of vanes to

machine understood language. necessery coordinats determined to adjust tool and tool path.

7.1 CNC

Numerical control (NC) refers to the automation of machine tools that are operated by

abstractly programmed commands encoded on a storage medium, as opposed to controlled

manually via handwheels or levers, or mechanically automated via cams alone. The first NC

machines were built in the 1940s and 1950s, based on existing tools that were modified with

motors that moved the controls to follow points fed into the system on punched tape. These

early servomechanisms were rapidly augmented with analog and digital computers, creating

the modern computer numerical control (CNC) machine tools that have revolutionized the

machining processes.

In modern CNC systems, end-to-end component design is highly automated using

computer-aided design (CAD) and computer-aided manufacturing (CAM) programs. The

programs produce a computer file that is interpreted to extract the commands needed to

operate a particular machine via a postprocessor, and then loaded into the CNC machines for

production. Since any particular component might require the use of a number of different

tools-drills, saws, etc., modern machines often combine multiple tools into a single "cell". In

other cases, a number of different machines are used with an external controller and human or

robotic operators that move the component from machine to machine. In either case, the

complex series of steps needed to produce any part is highly automated and produces a part

that closely matches the original CAD design.

7.2 Portable Horizontal Boring and Milling Machine (Bohrwerk)

To make repair or production . Suitable for sites and faraway areas Portable Horizontal

Boring and Milling Machine (Bohrwerk).This machine is perfect for construction sites,

faraway production areas , any case of broken equipments that can not moveable

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positions ,you can make repair your exist holes on your machine or you can open completly

new holes . Very practic and basic operating machine .

8 CHECKING OF VANES WITH TEMPLATES

we made templates acording to vane sızes. And then we check the vane with this

templates.And then we processed other vanes.

9 ASSEMBLY

We combined flanş and vanes to make Stay ring .We use dye panetration test after

assembly (picture 6) to locate surface-breaking defects in material and in welding.

9.1 Dye panetration test

Inspection with a penetrating dye is used for nonmagnetic materials. The part is first

sprayed with a red coloured dye which penetrates in defects. Next, the oil is washed from the

surface leaving the residue in defects. Finally, a white coating is sprayed over the surfaces the

oil in the defects gradually oozes out on the white surface delineating them.

10 WELDING

We use arc welding.

10. Welding

Welding is the localised union of metals by fusion , diffusion or surface alloying ,

accompolished by applying heat and/or pressure with or without a filler material . It is a

joining process as well as forming process. As a forming process it competes with casting ,

working and machining ; and as a joining process it competes with riveting , bolting and other

mechanical methods. Inwelding , however, the parts are held together by inter atomic forces.

Brazing and Soldering processes are variants of welding in which the filler material has a

lower melting point than the base metals , and the joint is secured by the adhesion of molten

brazing or soldering alloy while the base metals remain in solid state. If the melting

temperature of the filler material is above 450°C, the process is called brazing whereas if it is

below 450°C the process is called soldering.

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10.1 arc welding

These processes use a welding power supply to create and maintain an electric arc

between an electrode and the base material to melt 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 sometimes protected by some type of inert or semi-inert gas, known as

a shielding gas, and filler material is sometimes used as well.

10.1.1 Electroslag Welding

Electroslag Welding (ESW) deposits the weld metal into the weld cavity between the two

plates to be joined. This space is enclosed by water cooled copper dams or shoes to prevent

molten slag from running off. The weld metal is produced from a filler wire that forms an

initial arc with the workpiece until a sufficient pool of liquid metal is formed to use the

electrical resistance of the molten slag.

This process requires special equipment used primarily for horizontal welds of very large

plates up to 36 inches or more by welding them in one pass as in large machinery and nuclear

reactor vessels.

There are also variations of ESW where shielding is provided by an appropriate gas and a

continuous arc is used to provide weld metal. These are termed Electrogas Welding or EGW

machines.

10.1.2 Fluxed-Core Arc-Welding

Click to view larger JPEG. Fluxed-Core Arc-Welding (FCAW) uses a

tubular electrode filled with flux that is much less brittle than the coatings on

SMAW electrodes while preserving most of its potential alloying benefits.

The emissive fluxes used shield the weld arc from surrounding air, or

shielding gases are used and nonemissive fluxes are employed. The higher

weld-metal deposition rate of FCAW over GMAW (Gas Metal Arc Welding)

has led to its popularity in joining relatively heavy sections of 1" or thicker.

Another major advantage of FCAW is the ease with which specific weld-

metal alloy chemistries can be developed. The process is also easily automated,

especially with the new robotic systems.

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10.1.3 Gas Metal-Arc Welding

Click to view larger JPEG. Gas Metal-Arc Welding (GMAW), also called Metal Inert Gas

(MIG) welding, shields the weld zone with an external gas such as argon, helium, carbon

dioxide, or gas mixtures. Deoxidizers present in the electrode can completely prevent

oxidation in the weld puddle, making multiple weld layers possible at the joint.

GMAW is a relatively simple, versatile, and economical welding apparatus to use. This is

due to the factor of 2 welding productivity over SMAW processes. In addition, the

temperatures involved in GMAW are relatively low and are therefore suitable for thin sheet

and sections less than ¼ inch.

GMAW may be easily automated, and lends itself readily to robotic methods. It has

virtually replaced SMAW in present-day welding operations in manufacturing plants.

10.1.4 Gas Tungsten-Arc Welding

Click to view larger JPEG. Gas Tungsten-Arc Welding (GTAW), also known as

Tungsten Inert Gas or TIG welding, uses tungsten electrodes as one pole of the arc to generate

the heat required. The gas is usually argon, helium, or a mixture of the two. A filler wire

provides the molten material if necessary.

The GTAW process is especially suited to thin materials producing welds of excellent

quality and surface finish. Filler wire is usually selected to be similar in composition to the

materials being welded.

Atomic Hydrogen Welding (AHW) is similar and uses an arc between two tungsten or

carbon electrodes in a shielding atmosphere of hydrogen. Therefore, the work piece is not part

of the electrical circuit.

10.1.5 Plasma Arc Welding

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Click to view larger JPEG. Plasma Arc Welding (PAW) uses electrodes and ionized

gases to generate an extremely hot plasma jet aimed at the weld area. The higher energy

concentration is useful for deeper and narrower welds and increased welding speed.

10.1.6 Shielded-Metal Arc Welding

Click to view larger JPEG. Shielded-Metal Arc Welding (SMAW) is one of the oldest,

simplest, and most versatile arc welding processes. The arc is generated by touching the tip of

a coated electrode to the workpiece and withdrawing it quickly to an appropriate distance to

maintain the arc. The heat generated melts a portion of the electrode tip, its coating, and the

base metal in the immediate area. The weld forms out of the alloy of these materials as they

solidify in the weld area. Slag formed to protect the weld against forming oxides, nitrides, and

inclusions must be removed after each pass to ensure a good weld.

The SMAW process has the advantage of being relatively simple, only requiring a power

supply, power cables, and electrode holder. It is commonly used in construction, shipbuilding,

and pipeline work, especially in remote locations.

10.1.7 Submerged Arc Welding

Click to view larger JPEG. Submerged Arc Welding (SAW) shields the weld arc using a

granular flux fed into the weld zone forming a thick layer that completely covers the molten

zone and prevents spatter and sparks. It also acts as a thermal insulator, permitting deeper heat

penetration.

The process is obviously limited to welding in a horizontal position and is widely used for

relatively high speed sheet or plate steel welding in either automatic or semiautomatic

configurations. The flux can be recovered, treated, and reused.

Submerged Arc Welding provides very high welding productivity….4-10 times as much as

the Shielded Metal Arc Welding process.

11 DIMENSIONAL CONTROL AFTER WELDING

We control the dimension’s of parts after welding to whether or not expansion of the

part after welding.

12 GRINDING AND CLEANING14

We used to grinding finish workpieces which must show high surface quality (e.g., low

surface roughness) and high accuracy of shape and dimension. As the accuracy in dimensions

in grinding is on the order of 0.000025mm, in most applications it tends to be a finishing

operation and removes comparatively little metal, about 0.25 to 0.50mm depth. However,

there are some roughing applications in which grinding removals high volumes of metal quite

rapidly. Thus grinding is a diverse field.

12.1 Grinding

Grinding is a finishing process used to improve surface finish, abrade hard materials, and

tighten the tolerance on flat and cylindrical surfaces by removing a small amount of material.

Information in this section is organized according to the subcategory links in the menu bar to

the left.

In grinding, an abrasive material rubs against the metal part and removes tiny pieces of

material. The abrasive material is typically on the surface of a wheel or belt and abrades

material in a way similar to sanding. On a microscopic scale, the chip formation in grinding is

the same as that found in other machining processes. The abrasive action of grinding

generates excessive heat so that flooding of the cutting area with fluid is necessary.

Reasons for grinding are:

1. The material is too hard to be machined economically. (The material may have been

hardened in order to produce a low-wear finish, such as that in a bearing raceway.)

2. Tolerances required preclude machining. Grinding can produce flatness tolerances of

less than ±0.0025 mm (±0.0001 in) on a 127 x 127 mm (5 x 5 in) steel surface if the

surface is adequately supported.

3. Machining removes excessive materia

13 NDT BEFORE HEAT TREATMENT BY ÇILTUĞ

We used to NDT test to examine the crack and othet defects in metal without breaking

the material before heat treatment .

13.1 Non Destructive Testing(NDT)

NDT is carried out to examine cracks and other defects in a metal without breaking the

material. They are very useful for detecting such things as cracks in weldments etc. The most

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basic NDT examination is that carried out by the naked eye to observe any surface features.

However, for interior examinations various techniques are available.

We used ;

-magnetic test(mt)

-ultrasonic test(ut)

-visual test(vt)

13.1.1 Magnetic Particle Testing (MT)

Magnetic particle testing is accomplished by inducing a magnetic field in a

ferromagnetic material and then dusting the surface with iron particles. The surface will

produce magnetic poles and distort the magnetic field in such a way that the iron particles are

attracted and concentrated making defects on the surface of the material visible.

13.1.2 In ultrasonic testing (UT)

Very short ultrasonic pulse-waves with center frequencies ranging from 0.1-15 MHz and

occasionally up to 50 MHz are launched into materials to detect internal flaws or to

characterize materials. A common example is ultrasonic thickness measurement, which tests

the thickness of the test object, for example, to monitor pipework corrosion.

Ultrasonic testing is often performed on steel and other metals and alloys, though it can

also be used on concrete, wood and composites, albeit with less resolution. It is a form of non-

destructive testing used in many industries including aerospace, automotive and other

transportation sectors.

13.1.3 Visual inspection

Visual inspection is a common method of quality control, data acquisition, and data analysis.

Visual Inspection, used in maintenance of facilities, mean inspection of equipment and

structures using either or all of human senses such as vision, hearing, touch and smell. Visual

Inspection typically means inspection using raw human senses and/or any non-specialized

inspection equipment. Inspections requiring Ultrasonic, X-Ray equipment, Infra-red, etc. are

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not typically considered as Visual Inspection as these Inspection methodologies require

specialized equipment and training.

14 NDT BEFORE HEAT TREATMENT BY COSTUMER

Costumer made NDT which same as making by ciltuğ.

15 HEAT TREATMENTS OF STAY VANES + STAY

We use heat treatment to emoving the resudual stress of material so we used annealing.we

use stress relief annealing and normalizing.

15.1 Heat treatment

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.

15.1.1 Effects of time and temperature

Time-temperature transformation (TTT) diagram for steel.

Proper heat treating requires precise control over temperature, time held at a certain

temperature and cooling rate.

With the exception of stress-relieving, tempering, and aging, most heat treatments begin

by heating an alloy beyond the upper transformation (A3) temperature. The alloy will usually

be held at this temperature long enough for the heat to completely penetrate the alloy, thereby

bringing it into a complete solid solution. Since a smaller grain size usually enhances

mechanical properties, such as toughness, shear strength and tensile strength, these metals are

often heated to a temperature that is just above the upper critical temperature, in order to

prevent the grains of solution from growing too large. For instance, when steel is heated

above the upper critical temperature, small grains of austenite form. These grow larger as

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temperature is increased. When cooled very quickly, during a martensite transformation, the

austenite grain size directly affects the martensitic grain size. Larger grains have large grain-

boundaries, which serve as weak spots in the structure. The grain size is usually controlled to

reduce the probability of breakage.

The diffusion transformation is very time dependent. Cooling a metal will usually

suppress the precipitation to a much lower temperature. Austenite, for example, usually only

exists above the upper critical temperature. However, if the austenite is cooled quickly

enough, the transformation may be suppressed for hundreds of degrees below the lower

critical temperature. Such austenite is highly unstable and, if given enough time, will

precipitate into various microstructures of ferrite and cementite. The cooling rate can be used

to control the rate of grain growth or can even be used to produce partially martensitic

microstructures. However, the martensite transformation is time-independent. If the alloy is

cooled to the martensite transformation (Ms) temperature before other microstructures can

fully form, the transformation will usually occur at just under the speed of sound.

When austenite is cooled slow enough that a martensite transformation does not occur, the

austenite grain size will have an effect on the rate of nucleation, but it is generally temperature

and the rate of cooling that controls the grain size and microstructure. When austenite is

cooled extremely slow, it will form large ferrite crystals filled with spherical inclusions of

cementite. This microstructure is referred to as "sphereoidite." If cooled a little faster, then

coarse pearlite will form. Even faster, and fine pearlite will form. If cooled even faster, bainite

will form. Similarly, these microstructures will also form if cooled to a specific temperature

and then held there for a certain time.

Most non-ferrous alloys are also heated in order to form a solution. Most often, these are

then cooled very quickly to produce a martensite transformation, putting the solution into a

supersaturated state. The alloy, being in a much softer state, may then be cold worked. This

cold working increases the strength and hardness of the alloy, and the defects caused by

plastic deformation tend to speed up precipitation, increasing the hardness beyond what is

normal for the alloy. Even if not cold worked, the solutes in these alloys will usually

precipitate, although the process may take much longer. Sometimes these metals are then

heated to a temperature that is below the lower critical (A1) temperature, preventing

recrystallization, in order to speed-up the precipitation

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15.1.2 Heat Treatent Techniques

Complex heat treating schedules, or "cycles," are often devised by metallurgists to

optimize an alloy's mechanical properties. In the aerospace industry, a superalloy may

undergo five or more different heat treating operations to develop the desired properties. This

can lead to quality problems depending on the accuracy of the furnace's temperature controls

and timer

15.1.2.1 Annealing

Annealing is a rather generalized term. Annealing consists of heating a metal to a

specific temperature and then cooling at a rate that will produce a refined microstructure.

Annealing is most often used to soften a metal for cold working, to improve machinability, or

to enhance properties like electrical conductivity.

In ferrous alloys, annealing is usually accomplished by heating the metal beyond the

upper critical temperature and then cooling very slowly, resulting in the formation of pearlite.

In both pure metals and many alloys that can not be heat treated, annealing is used to remove

the hardness caused by cold working. The metal is heated to a temperature where

recrystallization can occur, thereby repairing the defects caused by plastic deformation. In

these metals, the rate of cooling will usually have little effect. Most non-ferrous alloys that are

heat-treatable are also annealed to relieve the hardness of cold working. These may be slowly

cooled to allow full precipitation of the constituents and produce a refined microstructure.

Ferrous alloys are usually either "full annealed" or "process annealed." Full annealing

requires very slow cooling rates, in order to form coarse pearlite. In process annealing, the

cooling rate may be faster; up to, and including normalizing. The main goal of process

annealing is to produce a uniform microstructure. Non-ferrous alloys are often subjected to a

variety of annealing techniques, including "recrystallization annealing," "partial annealing,"

"full annealing," and "final annealing." Not all annealing techniques involve recrystallization,

such as stress relieving.

15.1.2.2 Normalizing

It consists of heating the steel to its hardening temperature, 50°C above its critical range,

holding it there for 10-20 minutes, and then cooling it in free still air. The normalizing

treatment refines the grain of steel which was coarsened due to forging or welding. This

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treatment is applied mainly to plain medium carbon and low alloy steels. Normalizing may

also be used to improve machinability, modify and refine cast dendritic structures.

15.1.2.3 Stress relieving annealing

Stress relieving is a technique to remove or reduce the internal stresses created in a metal.

These stresses may be caused in a number of ways, ranging from cold working to non-

uniform cooling. Stress relieving is usually accomplished by heating a metal below the lower

critical temperature and then cooling uniformly.

16 NDT AFTER HEAT TREATMENT

We used to NDT test to examine the crack and othet defects in metal without breaking

the material after heat treatment .

SPIRAL CASE MANUFACTURING

17 CUTTING

We opened the part of spiral case and we take its dimension in autocad.then we entered

the dimension of stay ring to plasma arc cutting. And sheet was cuting.

18 BENDING

We bended big part of spiral case in Hydraulic Steel Plate Bending Machine and small

part in Hydraulic Abkant Pres Machine. We use cold working.

18.1 Cold Working

The dislocations tructure of cold worked metals consists of a cellular substructure with

the cell walls composed of tight-packed tangles of dislocations . For the large plastic strains

characteristics of wire drawing and rolling, structure consists of highly elongated grains .

On macroscopic scale, the structure of severely cold-worked metal is characterized by

the development of a strong crystallographic texture the presence of preferred orientation

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causes anisotropy of mechanical properties this is of particular importance in determining the

deep-drawing properties of rolled sheet.

18.1.1 Hydraulic Steel Plate Bending Machine

Hydraulic Steel Plate Bending Machine(picture 7) is a machine for bending and

straightening metal sheets and strips.

Sheet-bending machines with a rotary bending beam are designed for cold linear bending

to produce parts of various shapes, as well as pipes on mandrels; to form flanges and closed

contours; and for straightening sheet material. A turning beam and a bending beam are

mounted on the machine frame. Bending is accomplished by rotating the bending beam. The

turning beam holds the part in place and may be positioned as required by the thickness of the

article and the bending radius. The drive of such machines may be mechanical or hydraulic.

Machines of this type are used for bending sheets 0.8–5.0 mm thick.

Rotary-roll bending machines are designed for bending and straightening parts of

boilers, high-pressure vessels, and converters, as well as pipes with diameters exceeding 300

mm. Articles are formed in such machines during the simultaneous passage of the sheet stock

between the bending rolls and its lateral bending. The rolls are usually mounted horizontally.

Machines are produced with three rolls, which may be arranged symmetrically or

asymmetrically, or with four rolls. Roll bending machines are used for cold or hot bending of

stock 1–150 mm thick (plate thickness, more than 50 mm); the speed of bending is 3–8

m/min.

18.1.2 Hydraulic Abkant Pres Machine

Hydraulic bending machine(picture 8), including brackets, table and clamping plate, the

table placed in the bracket, Workbench from the platen base and base connected by a hinge

and the clamping plate, the base of the seat shell, coil and cover, coil placed in the seat shell

depression, the depression at the top covered with a lid. used by the wire coil is energized,

power on the platen gravity, thereby clamping the sheet between the platen and the base due

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to the electromagnetic force folder hold the plate can be made into a variety of workpiece

requirements, but also on the sidewall of the workpiece to be processed.

19 PREASSEMBLY

we combine flanges and pipes.

SC Main Assembly

20 MAIN ASSEMBLY

We combine All part of spiral case(stay ring ,flanges ,pipes…) (picture 9-10)

21 MAIN WELDING

(picture 11)

22 NDT AFTER ASSEMBLY BY ÇİLTUĞ

We used to NDT test to examine the crack and othet defects in metal without breaking the

material after assembly.

23 NDT AFTER ASSEMBLY BY COSTUMER

Costumer used to NDT test to examine the crack and othet defects in metal without breaking

the material after assembly.

24 MAIN MACHINING AND DRILLING

We do main machinig to remove extra material’s with chip removal processes (picture 12).

And we hole the flange to assembly.

25 DIMENSIONAL CHECK

We chack to dimensions after all machining and main assembly.

26 HYDROSTATIC TEST 22

A hydrostatic test is a way in which pressure vessels such as pipelines, plumbing, gas

cylinders, boilers and fuel tanks can be tested for strength and leaks. The test involves filling

the vessel or pipe system with a liquid, usually water, which may be dyed to aid in visual leak

detection, and pressurization of the vessel to the specified test pressure. Pressure tightness can

be tested by shutting off the supply valve and observing whether there is a pressure loss. The

location of a leak can be visually identified more easily if the water contains a colorant.

Strength is usually tested by measuring permanent deformation of the container. Hydrostatic

testing is the most common method employed for testing pipes and pressure vessels. Using

this test helps maintain safety standards and durability of a vessel over time. Newly

manufactured pieces are initially qualified using the hydrostatic test. They are then re-

qualified at regular intervals using the proof pressure test which is also called the modified

hydrostatic test.[citation needed] Testing of pressure vessels for transport and storage of gases

is very important because such containers can explode if they fail under pressure.

27 SAND BLASTING AND PAINTING

27.1 Sand blasting

Sand-blasting is done by throwing practicles at higt velocity against the work. The

particle may be metallic grit, artificial or natural abrasive including sand or agricultural

products depending upon the what is to be done and the condition of the workpiece. A

primary reason for blasting is to clean surface. This may mean removing scale, rust, or burnt

sand from casting by mean of sand, stripping paint by sand-blasting from objects to be

redecorated, cleaning grease or oil from fnişhing part by means of operations. A clean,

uniform, and in many cases final surface finish is obtained by blasting.

Common way of blasting is bycompressed air which’s equipment can be used with any

type of abrassive, is easily controlled, is simple and relatively inexpensive, and gives ready

acces to inside surface.

27.2 Painting

Painting may be done by brush, knife, dip, roller, flow, tumble, silk screen, or spray

methods. Brushing is easyly done but is slow, and other methors are used for production.

Dipping demands little equipment and can be machinized easily but requires paint that films

out, stiring, and workpiece that can be immersed easily and are without pockets.

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Paint spraying is the most used method of indistrial painting because it is fast,

dependable, versatile, and uniform. It is based on the principle that a liquid stream atomizes

when it exceeds a certain speed. The most common system is to introduce the liquid into a

hight velocity stream of compressed air released through a small orifice at pressures up to

5000 psi. In still another way, the painting may be slung off the edge of a rapidly revolving

disc or bell-shaped atomizer.

A spray gun or head may be directed by hand, but continuous production many

ingenious arrangements are in use to spray pieces automatically as they pass along a

conveyor. Manual torch-up at the end of such a line is usually necessery, but the labor cost is

normally less than if each piece were sprayed complately.

Because of the toxicity and flamability of most points, painting is generally done in

segregated enclosures or boths which are well ventilated. The exhausted air is generally done

in segregated enclosures or boths which are well ventilated. The exhausted air may be washed

to removed fumes and waste.

28 SUBMISSION OF QUALITY FILE

29 PACKING AND SHIPMENT

CASTING

INTRODUCTION

Casting is a manufacturing process where a solid is melted, heated to proper temperature

(sometimes treated to modify its chemical composition), and is then poured into a cavity or

mold, which contains it in the proper shape during solidification. Thus, in a single step,

simple or complex shapes can be made from any metal that can be melted. The resulting

product can have virtually any configuration the designer desires.

In addition, the resistance to working stresses can be optimized, directional properties

can be controlled, and a pleasing appearance can be produced.

Cast parts range in size from a fraction of an inch and a fraction of an ounce (such as the

individual teeth on a zipper), to over 30 feet and many tons (such as the huge propellers and

stern frames of ocean liners). Casting has marked advantages in the production of complex 24

shapes, parts having hollow sections or internal cavities, parts that contain irregular curved

surfaces (except those made from thin sheet metal), very large parts and parts made from

metals that are difficult to machine. Because of these obvious advantages, casting is one of the

most important of the manufacturing processes.

Today, it is nearly impossible to design anything that cannot be cast by one or more of

the available casting processes. However, as in all manufacturing techniques, the best results

and economy are achieved if the designer understands the various options and tailors the

design to use the most appropriate process in the most efficient manner. The various processes

differ primarily in the mold material (whether sand, metal, or other material) and the pouring

method (gravity, vacuum, low pressure, or high pressure). All of the processes share the

requirement that the materials solidify in a manner that would maximize the properties, while

simultaneously preventing potential defects, such as shrinkage voids, gas porosity, and

trapped inclusions

1 CASTING PROCESSES

Understanding the metalcasting basics can help you design for manufacturability and

utilize processes that meet your specific requirements.

The fundamental process of metalcasting consists of five basic elements:

Molding—The mold cavity must be formed from a material that will withstand the operating

temperatures and conditions of the chosen casting process and metal.

Pouring—The molten metal is poured into the mold and travels through its passages to fill

the mold cavity.

Solidification—During the solidification process, the metal cools and becomes a solid shape.

Mold Removal—The cooled casting is removed from the mold.

Secondary Operations—The casting is trimmed, cleaned, heat-treated, machined, inspected,

painted, etc.

These five basic elements are supported by design and fabrication of the patterns and

cores for the mold, the fabrication of the mold cavity and the melting of the metal.

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Cores are a crucial element in the process of designing a mold Cores are preformed

masses of bonded sand or other material that are used to make the internal passageways of a

casting. Castings may require a single core, a complex assembly of cores or none at all. Like

castings, cores are made in a mold, called a corebox. Typically, these cores are made of sand

and may be combined with other binding materials. Metal cores are used in permanent mold

and die casting processes. Choosing the type of core used in each metalcasting will be a key

element in your project.

2 PATTERN

In casting, a pattern is a replica of the object to be cast, used to prepare the cavity into

which molten material will be poured during the casting process.

Patterns used in sand casting may be made of wood, metal, plastics or other materials.

Patterns are made to exacting standards of construction, so that they can last for a reasonable

length of time, according to the quality grade of the pattern being built, and so that they will

repeatably provide a dimensionally acceptable casting.

2.1 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 of tool and die making and

moldmaking, but also often incorporates elements of fine woodworking. Patternmakers

(sometimes styled pattern-makers or pattern 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

2.2 Materials used

Typically, materials used for pattern making are wood, metal or plastics. Wax and

Plaster of Paris are also used, but only for specialized applications. Mahogany is the most

commonly used material for patterns, primarily because it is soft, light, and easy to work. The

downside is that it wears out fast, and is prone to moisture attack. Metal patterns are more

long lasting, and do not succumb to moisture, but they are heavier and difficult to repair once

damaged.

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Wax patterns are used in a casting process called investment casting. The main

advantage of wax patterns is that it can be reused multiple times. A combination of paraffin

wax, bees wax and carnauba wax is used for this purpose.

Plaster of paris is usually used in making master dies and molds, as it gains hardness

quickly, with a lot of flexibility when in the setting stage.

3 CASTING TYPES 3.1 Investment casting

The investment casting process was one of the first processes used to produce metal

castings. The process has been described as the lost wax process, precision casting and

investment casting. The latter name generally has been accepted to distinguish the present

industrial process from artistic, medical and jewelry applications.

In investment casting, patterns are produced in dies via injection molding. For the most

part, the patterns are made of wax; however, some patterns are made of plastic or polystyrene.

Because the tooling cost for individual wax patterns is high, investment casting normally is

used when high volumes are required. When cores are required, they are made of soluble wax

or ceramic materials.

The ceramic shell is built around a pattern/gating assembly by repeatedly dipping the

"tree" into a thin refractory slurry. After dipping, a refractory aggregate, such as silica, zircon

or aluminum silicate sand, is rained over the wet slurry coating. After each dipping and

stuccoing is completed, the assembly is allowed to dry thoroughly before the next coating is

applied. Thus, a shell is built up around the assembly. The required thickness of this shell is

dependent on the size of the castings and temperature of the metal to be poured. After the

ceramic shell is complete, the entire assembly is placed into an autoclave oven to melt and

remove a majority of the wax.

Some of the advantages of investment casting include excellent surface finishes, tight

dimensional tolerances, reduced or eliminated machining requirements, and the ability to cast

titanium and other superalloys.

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Rapid Prototyping (RP) most commonly is used with investment casting to produce an

actual cast part to test for form, fit and function, as well as to determine the approximate final

properties of the cast parts. RP models for investment casting are created by converting a 3-D

CAD model into an STL file. The file then is printed three-dimensionally using either

photopolymer, thermopolymer, polystyrene or other materials, depending on the RP method.

The prototype models then can be attached to a gating system and processed through typical

investment casting to produce cast prototype parts.

3.2 Sand casting manufacturer

Fundamentally, sand casting is a process where a mold is produced by shaping a

refractory material to form a cavity of a desired shape such that molten metal can be poured

into the cavity. The mold cavity needs to retain its shape until the metal has solidified and the

casting is removed. This sounds easy to accomplish, but depending on the choice of metal,

certain characteristics are demanded of the mold. As a sand casting manufacturer, Monmet

has the knowledge and experience required to produce efficient molds.

3.2.1 Green sand molding

The most common method used in sand casting manufacturing is green sand molding. In

this process, granular refractory sand is coated with a mixture of bentonite clay, water and, in

some cases, other additives. The additives help to harden and hold the mold shape to

withstand the pressures of the molten metal.

The green sand mixture is compacted through mechanical force or by hand around a

pattern to create a mold. The mechanical force needed for the sand casting process can be

induced by slinging, jolting, squeezing or by impact/impulse.

For many metal applications, green sand casting processes are the most cost-effective of

all metal forming operations; these processes readily lend themselves to automated systems

for high-volume work as well as short runs and prototype work. In the case of slinging,

manual jolt or squeeze molding to form the mold, wood or plastic pattern materials can be

used. High-pressure, high-density sand casting and molding methods almost always require

metal pattern equipment. High-pressure, high-density molding normally produces a well-

compacted mold, which yields better surface finishes, casting dimensions and tolerances. The

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properties of green sand casting are adjustable within a wide range, making it possible to use

this process with all types of green sand molding equipment and for a majority of alloys

poured. As a sand casting manufacturer, Monmet offers green sand casting services which

produce better molds.

CONCLUSİON

This summer practice was very usefull for me. I have learned lots of things that I will use

in the future and I saw many different machines. I improved my practice, by the help of the

workers in çiltuğ. I have good relations with the engineers, workers and asked some question

to them about the life after graduation and how can improve my skills. The summer practice

for junior year students depends on the analysis of production techniques and application of

school knowledge in industry

In this summer practice, I think I had useful practices on production techniques and I see

what is going on in the factory about production. And I think I got knowledge about

application of theory in practice. I think my summer practice was corresponding with the aim

of the summer practice and I worked on the scope of the summer practice.

I saw and learned what difference an engineer from a worker and how engineers work

themselves or all together, also relations between engineers and workers.

Also in summer practice I had chance to see the production and apply my knowledge to

practice. In the factory I saw all the stages of production. It was actually educational. I saw what is

going on in production. What is the production sequence? What are the operations after a half-

product or a raw material came to factory? How a part is machined? How the controls are done? I

found answers to such questions.

In Çiltuğ company has been making importand education which improves the engineers’

experience and some workers’ efficiency. I think that I have applied my theoretical knowledge on

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production and drawing, to practice. Finally, this was good experience for me before working at

any company.

Picture 1. spiral case

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Picture 2. stay ring

picture 3. Plasma arc cutting

31

picture 4. vertical lathe

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pictre 5. Cnc borhwerg

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picture 6. dye panetration of stay ring after assembly

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picture 7. Hydraulic Steel Plate Bending Machine (With Three Rolls)

picture 8 Hydraulic bending machine

35

Picture 9. main assembly

36

Picture 10. main assembly

Picture 11. main welding

37

Picture 12. main machining

38

39