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CONTENTS

1. INTRODUCTION4

2. DESCRIPTION OF THE COMPANY!2.1) "#$a%n #' %he (#mpany) !

2.2) *&+%#ry #' %he (#mpany,

2.3) -a&n Area ab#u% %he (#mpany,

2.4) Number #' S%a'' and .&+%r&bu%n #' En&neer+,

2.5) un$%n+ #' -e$han&$a1 En&neer+ &n %he (#mpany7

2.6) &+n 3 -&++n #' NTES)7

2.7) 5ran&za%na1 S%ru$%ure #' %he (#mpany)))))))))))))6

3) MANUFACTURING STEPS 6

3.1 8npu%+ #' %he a$%#ry))))))))))))))6

3.2)Pr#$e++e+ 3 -a$h&ne+)))))6

3.3)Pr#du$%n 1#)))))))))))))))))))))))))

4) PRODUCTION TECHNIQUES USED IN THE ORGANIZATION)))))))2

4.1) -a%er&a1 Rem#;a1 Pr#$e++e+ )))))))) 2

4.1.1) (u%%&n))))))))))))))))))))))))ue1 ?a+ (u%%&n))))!

b) 5p%&$a1 5=y>ue1 ?a+ (u%%&n!

4.1.1.3) Shear&n!

4.1.1.4) Sa&n)))))),

4.1.2) -&11&n))))))))))))))))))))))7

4.1.3) Turn&n)))))))))))))))))))))))20

4.1.4) .r&11&n)))))))))))))))))))))))))2ith approval of !uality

management manager, projects start in &'#(.

Bremanufacturing chief determines the necessary materials and informs warehouse official chief

about them. "t the same time, these inputs of the plant which are used in the certain project are

tested in !uality assurance department. :asically, all materials are inspected after each production

unit by !uality management system. >arehouse chief founds re!uired materials and gives them

presand blasting part of the plant. "nd then these materials are taken premanufacturing chief

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responsibility. +utting and drilling processes are made in these +'+ and '+ based machines.

:esides radial drilling machines, *3 saws, band saws, optical shearing plate machine are used

depending on materials characteristics and machining properties and sensitivity. "dditionally,

+hief divides and distributes materials in shares among workbenches taking into their activities. I

will give detailed information about each process and each property of these machines later on.

(heared and drilled materials are marked these cutting and drilling workbench. ?arking consists

of project number, pose number and foreman name that will take the materials and assemble with

his team. :esides grinding process has a part in premanufacture hole because of removing burr

on the steel plate or fin on a casting material causing of cutting and drilling process.

Blant manager distributes the duty to appropriate teams with respect to their !ualifications. "fter

these processes, marked work pieces are being distributed to area of each foreman team.?anufacturing chief now takes the responsibility of the work from premanufacturer. )e watches

closely the products and their processes. "s seen above that Erganizational structure of this

procedure is !uite hierarchical.

In manufacturing holes, there are 16 team and their welding units. #aken materials are pre

assembled by each team. "nd then !uality control management controls each this preassembled

unit. 'ecessary measurements and observations are done by !uality controllers who work both in

the name of &'#( and +ooperation +ompany. +ontrolled work piece assembled with various

welding techni!ues being mentioned later on. "lso I will mention about the control techni!ues of

welded materials under their own title. Drinding, welding, annealing, assembling, some drilling

and cutting operations go on in these holes.

=inally, manufactured parts of some cement factory or mechanical e!uipments of the construction

area given the sand blasting machine generally. If the product dimensions are much higher than

machine, it is subjected to hand sandblasting process. (maller or the same size spherical steel

grains are used in final shotblasting corresponding with presand blasting process. (ome errors

of the material appear after blasting. :urrs and fins of the materials are cleaned after these

procedures by grinding and emery.

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4. 0-(3&T(N TEN8&ES &SE3 N TE

(-/AN9AT(N

4.1. Material -emo:al 0rocesses

In material removal processes, a sharp cutting tool is used to mechanically remove material to

achieve the desired geometry. #his process is also called machining. "s in all organizations,

machining is very important manufacturing process in &'#(, since almost all materials re!uire

machining at some stage of their production.

#he three principal machining processes are turning, drilling and milling. #he other machining

operations include shaping, planing, broaching and sawing. #he machining processes used in the

organization areA sawing, reaming, shaping, grinding, milling, drilling and related hole makingprocesses, turning, boring and related processes.

?achining is a manufacturing process in which a sharp cutting tool is used to cut away material

to leave the desired part shape. #he predominant cutting action in machining involves shear

deformations of the work material to form a chipF as the chip is removed, a new surface is

e;posed. ?achining is most fre!uently applied to shape metals.

4.1.1 utting

+utting processes are separated in different types.

4.1.1.1. 0lasma Arc utting

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#he plasma arc process has always been seen as an alternative to the o;yfuel process. In this part

of the series the process fundamentals are described with emphasis being placed on the operating

features and the advantages of the many process variants.

0rocess Fundamentals

#he basic principle is that the arc formed between the electrode and the work piece is constricted

by a fine bore, copper nozzle. #his increases the temperature and velocity of the plasma

emanating from the nozzle. #he temperature of the plasma is in e;cess of 2 G+ and the

velocity can approach the speed of sound. >hen used for cutting, the plasma gas flow is

increased so that the deeply penetrating plasma jet cuts through the material and molten material

is removed in the efflu; plasma.#he process differs from the o;yfuel process in that the plasma process operates by using the arc

to melt the metal whereas in the o;yfuel process, the o;ygen o;idises the metal and the heat

from the e;othermic reaction melts the metal. #hus, unlike the o;yfuel process, the plasma

process can be applied to cutting metals which form refractory o;ides such as stainless steel,

aluminum, cast iron and nonferrous alloys.

0o7er source

#he power source re!uired for the plasma arc process must have a drooping characteristic and a

high voltage. "lthough the operating voltage to sustain the plasma is typically 7 to 6*, the

open circuit voltage needed to initiate the arc can be up to %* $+.

En initiation, the pilot arc is formed within the body of the torch between the electrode and the

nozzle. =or cutting, the arc must be transferred to the workpiece in the socalled HtransferredH arc

mode. #he electrode has a negative polarity and the workpiece a positive polarity so that the

majority of the arc energy appro;imately two thirds4 is used for cutting.

/as com!osition

In the conventional system using a tungsten electrode, the plasma is inert, formed using argon, or

argon)2, or nitrogen. )owever, o;idizing gases, such as air or o;ygen, can be used but the

electrode must be copper with hafnium.

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#he plasma gas flow is critical and must be set according to the current level and the nozzle bore

diameter. If the gas flow is too low for the current level, or the current level too high for the

nozzle bore diameter, the arc will break down forming two arcs in series, electrode to nozzle and

nozzle to workpiece. #he effect of Hdouble arcingH is usually catastrophic with the nozzle melting.

ut ;ualit"

#he !uality of the plasma cut edge is similar to that achieved with the o;yfuel process. )owever,

as the plasma process cuts by melting, a characteristic feature is the greater degree of melting

towards the top of the metal resulting in top edge rounding, poor edge s!uareness or a bevel on

the cut edge. "s these limitations are associated with the degree of constriction of the arc, several

torch designs are available to improve arc constriction to produce more uniform heating at the top

and bottom of the cut.

4.1.1.2 N (*"Fuel /as utting

In these machines the plates being formed are sheared by computer based machines. :asically,

plate beds to worktable and controlled by the workers. ?achine switch is opened and o;ygen, gas

valves are regulated according to their pressure. #his pressure, cutting speed and nozzle table isgiven in the appendi; +'+'+ cutting machines. +utting system is chosen in kind of o;ygen or

plasma. #he nozzles that are specific for all cut materials are attached. "fter this procedure,

relevant cutting program that is used opened in the computer and cutting process starts from

chosen reference point. #his program is written by engineers in the disk and given to relevant

workers. #hickness of the sheared plate determines the flame and speed of nozzle. In plasma

cutting, thinner material than 7 mm is cut by plasma. &sing plasma is much economic and

reliable but plasma nozzles have higher cost than o;ygen. =or this reason, once this nozzle is

damaged, it is hard to change. >ith o;ygen, these machines cut the plates with thickness up to

2 mm. +r'i alloying, aluminum, cast iron and +u can not be cut by o;ygen0 propane and

plasma type of shearing is applied for this type of plates.

4.1.1., (!tical (*"Fuel /as 0late utting Machine

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#his machine has the same principle with the +'+ plate shearing machine but different based.

Battern of the plate is drawn by the engineering department and given to relevant workers in

different to disk in the +'+. #his 2 dimensional pattern are put the stationary black table and one

sensor that has capability to distinct white and black. #his sensor follows the shape of patterns,

and nozzles cut the plates have the same shape. #hese machines older than +'+ based machine

but it is more fle;ible than +'+. "nd it is usually used in more comple; details.

4.1.1., Shearing

(hearing is the mechanical cutting of materials without the formation of chips by placing the

sheet between two edges of the shearing tools. If the blades are straight, the process is calledshearing, but if the blade geometry is curved, as in the edges of punches and dies, the process

have special names, such as blanking, piercing, notching and trimming. "ll of these are basically

shearing operations.

" simple type of shearing process is that the punch descends against the work piece then the

metal is first deformed plastically into the die. :ecause the clearance between the two tools is

only 7 to 1 of the thickness of the metal being cut, the deformation is highly localized. #he

punch penetrates into the metal, the material flows into the die, and the opposite surface bulgesslightly. >hen penetration reaches about 17 to 6 of thickness of the metal, the amount

depending upon the material ductility and strength, the applied stress e;ceeds the shear stress and

the metal suddenly shears or ruptures through the remainder of its thickness.

:ecause of the normal inhomogeneities in a metal and the possibility of nonuniform clearance

between the shear blades, the final shearing does not occur uniformly. =racture and tearing start at

the weakest points and proceed progressively and intermittently to the ne;t stronger locations.

#he result is a rough and ragged sheared edge.If the punch and die have proper clearance and are maintained in good condition, sheared edges

may be produced that are sufficiently smooth to use without further finishing. #he !uality of the

sheared edge can be further improved if the strip stock is clamped firmly against the die from

above, the punch and die are maintained with proper clearance and alignment, and the movement

of the piece through the die is restrained by an opposing plunger or rubber die cushion applying

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pressure from below the work piece. #hese measures cause the shearing to take place uniformly

around the edge rather than randomly at the weakest points. #he major processing parameters in

shearing are the shape and materials for the punch and die, the speed of punching, lubrication and

the clearance between the punch and die.

4.1.1.4. Sa7ing

(awing is a basic machining process in which chips are produced by a succession of small cutting

edges, or teeth, arranged in a narrow line on a saw JbladeK. ach tooth forms a chip progressively

as it passes through the work piece, and the chip is contained within the space between two

successive teeth until these pass from the work. :ecause sections of considerable size can besevered from the work piece with the removal of only a small amount of the material in the form

of chips, sawing is the most economical of the basic machining processes with respect to the

waste of material and power consumption, and in many cases with respect to labor. In recent

years vast improvements have been made in saw blades and sawing machines, resulting in

improved accuracy and precision of the process.

Sa7ing machine in &NTES

+ircular saw and band saw are belonging to this group in &'#(. #hese saws can have different

kind of cutting shape. In these workbenches, hydraulics, air pressure and progress speed must be

arranged. Bipes, I& beam and profiles are cut to desired length in these machines. :and saws can

cut larger materials than circle saws. In the band saws, ma;imum 621 mm dimensions

materials are cut, where as in the circular saw machine ma;imum %77mm dimensionalmaterials are being cut. $isadvantage of the band saw is slower than the circular one. )orizontal

cutting saw machine cuts the angle bracket because of its fast and reliability.

4.1.2 Milling

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?illing is a machining operation in which a workpart is fed past a rotating cylindrical tool with

multiple cutting edges in rare cases, a too with one cutting edge, called a flycutter, is used4. #he

a;is of rotation of the cutting tool is perpendicular to the direction of feed. #his orientation

between the tool a;is and the fees direction is one of the features that distinguish milling from

drilling. In drilling, the cutting tool is fed in a direction parallel to its a;is of rotation. #he cutting

tool in milling is called a milling cutter and the cutting edges are called teeth. #he machine tool

that traditionally performs this operation is a milling machine.

#he geometric form created by milling is a plane surface. Ether work geometries can be created

either by means of the cutter path or the cutter shape. Ewing to the variety of shapes possible and

its high production rates, milling is one of the most versatile and widely used machining

operations.

?illing is an interrupted cutting operationF the teeth of the milling cutter enter and e;it the work

during each revolution. #his interrupted cutting action subjects the teeth to a cycle of impact

force and thermal shock on every rotation. #he tool material and cutter geometry must be

designed to withstand these conditions.

T"!es of milling o!erations

#here are two basic types of milling operationsF

a) peripheral milling

b) face milling

0eri!heral milling

In peripheral milling, also called plain milling, the a;is of the tool is parallel to the surface being

machined, and the operation is performed by cutting edges on the outside periphery of the cutter.

T"!es of !eri!heral milling+

Slab millingA

#he basic form of peripheral millingF the cutter width e;tends beyond the workpiece on both

sides.

SlottingA

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(lotting is also called slot milling. #he width of the cutter is less than the workpiece width,

creating a slot in the work. >hen the cutter is very thin, this operation can be used to mill narrow

slots or cut a workpart in two, called saw milling.

Side millingA

#he cutter machines the side of the workpiece.

Straddle millingA

#he same as side milling, only cutting takes place on both sides of the work.

In peripheral milling, the rotation direction of the cutter distinguishes two forms of millingA up

milling and down milling. In up milling, also called conventional milling, the direction of motion

of the cutter teeth is opposite the feed direction when the teeth cut into the work. It is milling

Lagainst the feedM. In down milling, also called climb milling, the direction of cutter motion is the

same as the feed direction when the teeth cut the work. It is milling Lwith the feedM.

#he relative geometries of these two forms of milling result in differences in their cutting actions.

In up milling, the chip formed by each cutter tooth starts out very thin and increases in thickness

during the sweep of the cutter. In down milling, each chip starts out thick and reduces in

thickness throughout the cut. #he length of a chip in down milling is less than in up milling. #his

means that the cutter is engaged in the work for less time per volume of material cut, and this

tends to increase tool life in down milling.

#he cutting force direction is tangential to the periphery of the cutter for the teeth that are

engaged in the work. In up milling, this has a tendency to lift the workpart as the cutter teeth e;it

the material. In down milling this cutter force direction is downward, tending to hold the work

against the milling machine table.

Face milling

In face milling, the a;is of the cutter is perpendicular to the surface being milled , and machining

is performed by cutting edges on both end and outside periphery of the cutter. "s in peripheral

milling, various forms of face milling e;istA

a) +onventional face millingA #he diameter of the cutter is greater than the workpart

width, so that the cutter overhangs the work on both sides.

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b4 Bartial face millingA #he cutter overhangs the work on only one side.

c4 nd millingA #he cutter diameter is less than the work width, so a slot is cut into the

part.

d4 Brofile millingA #his is a form of end milling in which the outside periphery of a flat

part is cut.

e4 Bocket millingA Bocket milling is another form of end milling, this is used to mill

shadow pockets into the flat parts.

g4 (urface contouringA " ballnose cutter is fed back and forth across the work along a

curvilinear path at close intervals to create a threedimensional surface form. #he same basic

cutter control is re!uired to machine the contours of molds and dies, in which case operations is

called die sinking.

4.1., Turning

#urning is a machining process in which a single point tool removes materials from the surface of

a rotating cylindrical workpieceF the tool is fed linearly in a direction parallel to the a;is of

rotation. #urning is traditionally carried out on a machine tool called a lathe, which provides

power to turn the part at a given rotational speed and to feed the tool at a specified rate and depth

of cut.

utting onditions in Turning &TTN/ 0-N0LE

A #he arbor can be made to revolve in either direction , but the tool will only cut in one

direction so the arbor must be checked to see that the direction is correct for the tool used. #here

are two cutting principlesA

&p milling is the most common .In this method the work moves in the opposite direction to the

rotation of the cutter. #his produces the least chattering and the better surface.

+limb milling is used only where necessary. #he work and tool move in the same direction.

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#he rotational speed in turning is related to the desired cutting speed at the surface of the

cylindrical workpiece by the e!uationA

/otational speed rev0min4A '

+utting speed m0min4A v

Eriginal diameter m4A $o

' N v 0 $o

#he turning operation reduces the diameter of the work from $o to final diameter $f. #he change

in diameter is determined by the depth of cut dA

$o O $f N 2d

#he feed in turning is generally e;pressed in mm0rev. #his feed can be converted to a linear travel

rate in mm0min by the formulaA

frN 'f

>here fr N feed rate mm0min4 and f N feed mm0rev4.

#he time to machine from one of a cylindrical workpart to the other is given by

#m N @0 fr

where #m N time of actual machiningminutes4F and @ N length of the cylindrical workpart, mm.

"s a practical matter, a small distance is usually added to the length at the beginning and end ofthe workpiece to allow for approach and over travel of the tool.

#he volumetric rate of material removal can be most conveniently determined by the following

e!uationA

?// N vfd

>here ?// N material removal rate mm30min4. In using this e!uation, the units for f are

e;pressed simply as mm, in effect neglecting the rotational character of turning. "lso, care must

be e;ercised to assure that the units for speed are consistent with those for f and d.

(!erations -elated to Turning

" variety of other machining operations can be performed on a lathe in addition to

turningF these include the followingA

a) Facing+#he tool is feed radially into the rotating work on one end to create a flat

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surface on one end.

b) Ta!er turningA Instead of feeding the tool parallel to the a;is of rotation of the work,

the tool is fed at an angle, thus creating a tapered cylinder or conical shape.

c) ontour turningA Instead of feeding the tool along a straight line parallel to the a;isof rotation as in turning, the tool follows a contour that is other than straight, thus creating a

contoured form in the turned part.

d) Form turningA In this operation, sometimes called forming, the tool has a shape that

is imparted to the work by plunging the tool radially into the work.

e) hamfering+#he cutting edge of the tool is used to cut an angle on the corner of the

cylinder, forming what is called a LchamferM.

f) utoff+#he tool is fed radially into the rotating work at some location along its length

to cut off the end of the part. #his operation is sometimes referred to as parting.

g) Threading+" pointed tool is fed linearly across the outside surface of the rotating

workpart in a direction parallel to the a;is of rotation at a large effective feed rate, thus creating

threads in the cylinder.

h) oring+" singlepoint tool is fed linearly, parallel to the a;is of rotation, on the inside

diameter of an e;isting hole in the part.

i) 3rilling+$rilling can be performed on a lathe by feeding the drill into the rotating

work along its a;is. /eaming can be performed in a similar way.

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bit. nurling is performed by a knurling tool, consisting of two hardened forming rolls, each

mounted between centers. #he forming rolls have the desired knurling pattern on their surfaces.

Stages of 3rilling (!eration in a Lathe

" lathe can be used to drill holes accurately concentric with the centerline of a cylindrical

part. =irst, a drill chuck is installed into the tailstock. It must be seen that that the tang on the back

of the drill chuck seats properly in the tailstock. #he jaws of the chuck are withdrawn and the

chuck is tapped in place with a soft hammer. #he saddle is moved forward to make room for the

tailstock. #he tailstock is moved into position, and it is locked in place otherwise it will slide

backward while drilling4. :efore starting the machine, spindle is turned by hand. #he saddle is

moved forward, so it could interfere with the rotation of the lathe chuck. "lways center drill mustbe used to start the hole. +utting fluid should be used with the center drill. It has shallow flutes

for added stiffness4 and doesnHt cut as easily as a drill bit.

"lways it should be drilled past the beginning of the taper to create a funnel to guide the bit in. "t

most one or two drill diameters of material should be taken before backing off, clearing the chips,

and applying cutting fluid. If the drill bit s!ueaks, solvent is applied more often. #he drill chuck

can be removed from the tailstock by drawing back the drill chuck as far as it will easily go, then

about a !uarter turn more. " pin will press the chuck out of the collet.

4.1.4. 3rilling

It is basically the production or enlarging of holes by the relative motion of a cutting tool and the

work piece that produce chips. #he cutting tool, the work piece or both may rotate with the tool

generally being fed. (everal methods of drilling e;ist, including conventional, deephole and small

hole drilling. >hile drilling is fast and economical, its cutting action is difficult and inefficient.

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+utting speed varies from a ma;imum at the periphery of the tool to zero at the center of the tool,

thus varying the load on the cutting edges. :oth chip rejection and flow of the cutting fluid are

restricted in drilling. In addition, the production of small, deep holes can create problems with

respect to the necessary rigidity of the tools.

+utting tools for drilling are rotary end cutting tools having one or more cutting lips and one

or more helical or straight flutes for the passage of the chips and the admission of the cutting fluid.

#he most common are helical fluted twist drills with various shanks and tip geometries. Ether types

include halfround, coolanthole, spade and inde; able insert drills. (ocalled pivot drills are used

for small holes. Dun drills, pressurecoolant drills and trepanning tools are used e;tensively for

precision and deep hole operations.

$rilling is a comple; threedimensional cutting operation with conditions varying along the

entire cutting edge. >hile the outer edge of the drill produces chips by shearing, work piecematerial under the chisel edge of the tool is subject to more severe deformation, thus re!uiring

greater thrust forces. +hip thickness, which varies with the feed rate, also has a major influence on

the chip formation. Increasing the feed, in turn the chip thickness, minimizes the possibility of the

flute clogging from coiled chips. ?a;imum feed, however, is limited by the structural strength of

the drill and the capacity of the machine.

$rilling has little effect on the physical properties of the work piece. #here is a thin layer of

highly stressed material around the drilled hole, which is often removed, the surfaces may be more

susceptible to corrosion. +lamping of work pieces for drilling may also result in distortion.

#he accuracy of any hole produced by drilling depends upon many factors, like the type of

the drilling process, the work piece, the tool and the machine used, operating parameters and the

rigidity of the setup. "ccuracy is also dependent upon the sharpness and the geometry of the drill

point.

$rilling is a machining operation used to create a round hole in a workpart. In contrast with

boring that can only be used to enlarge an e;isting hole. $rilling is usually performed with a

rotating cylindrical tool which has two cutting edges on its working end. #he tool is called a drill

or drill bit. #he rotating drill feeds into the stationary workpart to form a hole whose diameter is

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e!ual to the drill diameter. $rilling is customarily performed on a drill press, although other

machine tools can also perform this operation.

utting conditions in drilling

#he cutting speed in a drilling operation is the surface speed at the outside diameter of the drill. It

is specified in this way for convenience, even tough nearly all of the cutting is actually performed

at lower speeds closer to the a;is of rotation. #o set the desired cutting speed in drilling, it is

necessary to determine the rotational speed of the drill for its diameter. @etting ' represents the

spindle rev0min

' N v 0 $

>here vN cutting speed, mm0minF and $ N the drill diameter, mm. In some drilling operations,

the workpiece is rotated about a stationary tool, but the same formula applies.

=eed f in drilling is specified in mm0rev. /ecommended feeds are roughly proportional to drill

diameterF higher feeds are used with larger diameter drills. (ince there are two cutting edges at

the drill point, the uncut chip thickness chip load4 taken by each cutting edges is half the feed.

=eed can be converted to feed rate using the same e!uation as for turningA

frN 'f

>here frN feed rate, mm0min.

$rilled holes are either through holes or blind holes. In through holes, the drill e;its the oppositeside of the workF in blind holes, it does not. #he machining time re!uired to drill a through hole

can be determined by the following formula.

#m N t P "40fr

where #m N machiningdrilling4 time, minF frN feed rate, mm0minF and " N an approach

allowance that accounts for the drill point angle, representing the distance the drill must feed into

the work before reaching full diameter. #his allowance is given by

"N .7 $ tan8/2)

where " N approach allowance, mmF and N drill point angle.

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In a blind hole, hole depth d is defined as the distance from the work surface to the LpointM of the

hole. :y this definition, the drill point angle allowance does not affect the time to drill the hole.

#hus for a drill hole, machining time is given by

#m N d0 fr

#he rate of the metal removal in drilling is determined as the product of the drill cross

sectional area and the feed rateA

?// N $2fr0%

#his e!uation is valid only after the drill reaches full diameter and e;cludes the initial approach

of the drill into the work.

(!erations related to drilling

(everal operations are related to drilling. ?ost of the operations follow drillingF a hole must be

made first by drilling, and then the hole is modified by one of the other operations. +entering and

spotfacing are e;ceptions to this rule. "ll of the operations use rotating tools.

a) /eamingA /eaming is used to slightly enlarge a hole, to provide a better tolerance

on its diameter, and to improve its surface finish. #he tool is called a reamer, and it usually has

straight flutes.b) #appingA #his operation is performed by a tap and is used to provide internal

screw threads on an e;isting hole.

c) +ounterboringA +ounterboring provides a stepped hole, in which a larger diameter

follows a smaller diameter partially into the hole. " counterbored hole is used to seat bolt heads

into a hole so the heads do not produce above the surface.

d) +ountersinkingA #his is similar to counterboring, e;cept that the step in the hole is

coneshaped for flat head screws and bolts.

e) +enteringA "lso called centerdrilling, this operation drills a starting hole to

accurately establish its location for subse!uent drilling. #he tool is called a centerdrilling.

(potfacingA (potfacing is similar to milling. It is used to provide a flat machined surface on the

workpart in a localized area.

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4.1.5. oring

:oring is similar to turning. It uses a singlepoint tool against a rotating workpart. #he difference is

that boring is performed on the inside diameter of an e;isting hole rather than the outside diameter

of an e;isting cylinder. In effect, boring is an internal turning operation. ?achine tools used toperform boring operations are called boring machines. Ene might e;cept that boring machines

would have features in common with turning machinesF indeed as previously indicated, lathes are

sometimes used to accomplish boring. :oring always involves the enlarging of an e;isting

hole, which may have been made by a drill or may be the result of a core in a casting. +oncentricity

is an important attribute of bored holes. "nd so another important purpose of boring may be to

make the hole concentric with the a;is of rotation of the work piece and thus correct any

eccentricity that may have resulted from the drillMs having drifted off the center line.

:oring can be made on horizontal, vertical or angular machines as long as the machine

design provides the inherent rigidity and accuracy to produce the tolerances re!uired. +onsiderable

boring is done on the various types of lathes and also performed on some drilling machines.

"pplications of boring can be divided into heavy cutting and precision operations. )eavy boring is

generally done on large horizontal and vertical boring machines. Brecision boring is performed on

machines specially designed for this purpose. #hese machines generally take relatively light cuts,

maintain close tolerances and often capable of high production rates. Eperations often performed

with precision boring in the same cycle include facing, turning and grooving. ?achines are

sometimes arranged for accurate milling operations.

>hen boring is done in a lathe, the work usually is held in a chuck or on a faceplate. )oles

may be bored straight, tapered, or to irregular contours. :oring is essentially internal turning while

feeding the tool parallel to the rotation a;is of the work piece.

:oring always involves the enlarging of an e;isting hole, which may have been made by a

drill or may be the result of a core in a casting. +oncentricity is an important attribute of bored

holes. "nd so another important purpose of boring may be to make the hole concentric with the a;isof rotation of the work piece and thus correct any eccentricity that may have resulted from the

drillMs having drifted off the center line.

:oring can be made on horizontal, vertical or angular machines as long as the machine

design provides the inherent rigidity and accuracy to produce the tolerances re!uired. +onsiderable

boring is done on the various types of lathes and also performed on some drilling machines.

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"pplications of boring can be divided into heavy cutting and precision operations. )eavy boring is

generally done on large horizontal and vertical boring machines. Brecision boring is performed on

machines specially designed for this purpose. #hese machines generally take relatively light cuts,

maintain close tolerances and often capable of high production rates. Eperations often performed

with precision boring in the same cycle include facing, turning and grooving. ?achines are

sometimes arranged for accurate milling operations.

>hen boring is done in a lathe, the work usually is held in a chuck or on a faceplate. )oles

may be bored straight, tapered, or to irregular contours. :oring is essentially internal turning while

feeding the tool parallel to the rotation a;is of the work piece.

4.1.#. /rinding

#he grinding process is used to produce a high surface finish with a close tolerance and for

machining hard materials. #he process is a variation of polishing using abrasive materials held

together by an adhesive generally in the form of a solid wheel. #he wheel is rotated at high

speeds and the circumferential surface of the rotating wheel is brought into contact with the

material being machined.

#he reasons for grinding are removal of surplus material, production of high !uality

surface finishes and machining very hard materials

#he two main abrasives used for grinding wheels are aluminum E;ide for use on materials

with a high tensile strength4 and silicon +arbide for use on materials with a low tensile strength4.

#he grinding wheel variables includingA abrasive material, bonding material, abrasive

particle size etc are selected depending onA re!uired surface finish, metal removal rate, material,

wheel speed etc.

#here are different types of grinding machines as shown below.

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#he surface grinder is used in the tool room for the production of accurate flat surfaces.

#his machine has a similar layout to the horizontal milling machine but only removes small

thicknesses of material on the grinding passes.

#he cylindrical grinding machine is use to generate cylindrical surfaces and is similar to a

centre lathe in appearance. #he main difference is that the tool is replaced by a rotating grinding

wheel.

#he centreless grinding machine is for pure cylindrical prism shapes which do not re!uired

mounting. #he workpieces are fed through two parallel rotating wheelsA a conventional grinding

wheel and a rubberized regulating wheel. #he regulating wheel is inclined at a slight angle to

facilitate a;ial movement.

Drinding is a materialremoval process in which abrasive particles are contained in a bonded

grinding wheel that operates at very high surface speeds. #he grinding wheel is usually disk

shaped, and is precisely balanced for high rotational speeds.

Drinding can be likened to the milling process. +utting occurs on either the periphery or the face

of the grinding wheel, similar to peripheral milling and face milling. Beripheral grinding is much

more common than face grinding. #he rotating grinding wheel consists of many cutting teeth the

abrasive particles4, and the work is fed relative to the wheel to accomplish material removal.

The /rinding 6heel

" grinding wheel consists of abrasive particles and bonding material. #he bonding material holds

the particles in place and establishes the shape and structure of the wheel. #hese two ingredients,and the way they are fabricated, determine the parameters of the grinding wheel, which areA

1) "brasive material

2) Drain size

3) :onding material

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4) >heel grade

5) >heel structure

#hese parameters are analogous to the material and geometry of a conventional cutting tool. #o

achieve the desired performance in a given application, each of the parameters must be carefullyselected.

#he amount of chip removal for each grinding wheel is as followsF

1st sidefacemm4

2ndsidefacemm4

1stgrinding wheel ,1%7 ,18

2ndgrinding wheel ,1% ,1%

3rd grinding wheel ,5 ,5

/rinding (!erations and /rinding Machines

Drinding is traditionally used to finish parts whose geometries have already been created by other

operations. "ccordingly, grinding machines have been developed to grind plain flat surfaces,

e;ternal and internal cylinders and contour shapes such as threads. #he contour shapes are often

created by special formed wheels that have the opposite of the desired contour to be imparted to

the work. Drinding is also used in tool rooms to form the geometries on cutting tools. In addition

to these traditional uses, applications of grinding are e;panding to include more highmaterial

removal operations. Eur discussion of operations and machines in this section includes the

following typesA

1) surface grinding

2) cylindrical grinding

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3) centerless grinding

4) creep feed grinding

Surface /rinding

(urface grinding is normally used to grind plain flat surfaces. It is performed using either the

periphery of the grinding wheel or the flat face of the wheel. (ince the work is normally held in a

horizontal orientation, peripheral grinding is performed by rotating the wheel about a horizontal

a;is and face grinding is performed by rotating the wheel about a vertical a;is. In either case, the

relative motion of the workpart is achieved by reciprocating the work past the wheel or rotating

it. #hese possible combinations of wheel orientations and workpart motions yield the four types

Ef the four types, the horizontal spindle machine with reciprocating worktable is the mostcommon. Drinding is accomplished by reciprocating the work longitudinally under the wheel at a

very small depth and by feeding the wheel transversely into the work a certain distance between

strokes.

In addition to its conventional application, a grinding machine with horizontal spindle and

reciprocating table can be used to form special contoured surfaces by employing a formed

grinding wheel. Instead of feeding the wheel transversely across the work as it reciprocates, the

wheel is plungefed vertically into the work. #he shape of the formed wheel is therefore imparted

to the work surface.

Drinding machines with vertical spindles and reciprocating tables are set up so that the wheel

diameter is greater than the work width. "ccordingly, these operations can be performed without

using a transverse feed motion. Instead, grinding is accomplished by reciprocating the work past

the wheel and feeding the wheel vertically into the work to the desired dimension. #his

configuration is capable of achieving very flat surface on the work.

Ef the two types of rotary table grinding, the vertical spindle machines are more common. Ewingto the relatively large surface contact area between wheel and workpart, vertical spindlerotary

table grinding machines are capable of high metal removal rates when e!uipped with appropriate

grinding wheels.

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"lindrical /rinding

"s its name suggests, cylindrical grinding is used for rotational parts. #hese grinding operations

divide into two basic typesA

;ternal cylindrical grinding Internal cylindrical grinding

;ternal cylindrical grinding also called centertype grinding to distinguish it from centerless

grinding4 is performed much like a turning operation. #he grinding machines used for these

operations closely resemble a lathe in which the tool post has been replaced by a high speed

motor to rotate the grinding wheel. #here two types of feed motion possible, traverse feed and

plungecut. In traverse feed, the grinding wheel is fed in a direction parallel to the a;is of rotation

of the workpart. " longitudinal reciprocating motion is sometimes given to either the work or thewheel to improve surface finish. In plungecut, the grinding wheel is fed radially into the work.

;ternal cylindrical grinding is used to finish parts that have been machined to appro;imate size

and heat treated to desired hardness. Barts include a;les, crankshafts, spindles, bearings and

bushings and rolls for rolling mills. #he grinding operation produces the final size and re!uired

surface finish on these hardened parts.

enterless /rinding

+enterless grinding is an alternative process for grinding e;ternal and internal cylindrical

surfaces. "s its name suggests, the workpiece is not held between centers. #his results in a

reduction in work handling timeF hence, centerless grinding is often used for high production

work. #he setup for external centerless grindingconsists of two wheelsF the grinding wheel and

a regulating wheel. #he workparts, which may be individual short pieces or long rods are

supported by a rest blade and fed through between the two wheels. #he grinding wheel does the

cutting. #he regulating >heel rotates at much lower speeds and is inclined at a slight angle to

control through feed of the work.

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4.1.'. 0iercing and lan=ing

0iercing

Biercing is the operation of cutting internal features holes or slots4 in stock. Biercing can also be

combined with other operations such as lance and form to make a small feature such as tab4,pierce and e;trude to make an e;truded hole4. "ll these operations can be combined with

blanking.

Biercing of all the holes is best done together to ensure good holetohole tolerance and part

repeatability. )owever if the material distorts, the method described below can be done.

>hen there are large numbers of holes, in a tight pitch, there could be distortions, due to the high

amount of tension on the upper surface due to stretching and compression on the bottom surface.

#his causes the material not to lay flat. #his can be avoided0 lessened by staggering the piercing

of the holes. )oles are punched in a staggered patternF then the other holes are punched in the

alternate staggered pattern.

lan=ing

:lanking is cutting up a large sheet of stock into smaller pieces suitable for the ne;t operation in

stamping, such as drawing and forming. Eften this is combined with piercing.

:lanking can be as simple as a cookie cutter type die to produce prototype parts, or high speed

dies that run at 1P strokes per minute, running coil stock which has been slit to a specified

width.

=or production parts, the final configuration of the drawn or formed shape needs to be established

before the blank die can be builtsince the blank size and the slit width size needs to be

established precisely.

4.1.> Ta!!ing

Internal threads in work pieces can be produced by tapping. " tap is basically a threadingtool with multiple cutting teeth and they have usually three or four flutes. +hip removal can be a

significant problem during tapping because of the small clearances are involved .#he difficulty of

tapping relative to other cutting operations is that tapping is severe re!uires low cutting speeds

and it needs effective cutting fluids.

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4.2. Forming (!erations

4.2.1. ending

:ending is the plastic deformation of the metals about a linear a;is with little or no change in the

surface area by stressing the metal above its yield strength but not larger than its ultimate tensile

stress. >hen multiple bends are made simultaneously with the use of a die, the process is

sometimes called forming. #he various bend a;es can be at angles to each other, but each a;is

must be linear and independent of the others for the process to be classified as a true bending

operation. If the a;es of deformation are not linear or are not independent, the process becomes

one of drawing and0or stretching, not bending. +haracteristic of this process is stretching tensile

elongation4 imposed on the outer surface and compression on the inner surface. (ince the yieldstrength of metals in compression is somewhat higher than the yield strength in tension, the metal

on the outer side yields first, and the neutral a;is is displaced from the center of the two surfaces.

+oncerning the inner side of the bend, it is possible for the compressive forces to introduce

upsetting, which would cause the material to become longer in the direction parallel to the bend

a;is. #his effect can become !uite pronounced in the bending of thick, narrow pieces.

(till another conse!uence of the condition of combined tension and compression is the tendency

of the metal to unbend somewhat after forming, a phenomenon known as spring back. #o form adesired angle, metals must be over bent in such a way that upon spring back, the material

assumes the desired shape of the product.

4.2.1.1. Angle ending

" bar folder can be used to make angle bends up to 17 degree in sheet metal under about 1.7mm

in thickness. #he sheet of metal is inserted under the folding leaf and moved to proper position.

/aising the handle then actuates a cam, causing the leaf to clamp the sheet. =urther motion of the

handle then bends the metal to the desired angle. :ar folders are manually operated and are

usually less than %meters long.

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:ends in heavier sheet or more comple; bends in thin material are generally made on press

brakes. #hese are mechanically or hydraulically driven presses with a long, narrow bed and

relatively slow, short, adjustable strokes. #he metal is bent between interchangeable dies that are

attached to the bed and the ram. $ifferent dies can be used to produce many types of bends. #he

metal can be fed inward between successive strokes to produce various repeated bends, such as

corrugation. (eaming, embossing, punching, and other operations can also be performed by

inserting suitable dies into press brakes, but these operations can usually be done more efficiently

on other types of e!uipment when the volume is sufficient to justify their use.

4.,. ?oining 0rocesses

4.,.1. 6elding

>elding is a process in which two materials, usually metals, are permanently joined together by

coalescence, the coalescence resulting from a combination of temperature, pressure, and

metallurgical conditions. #he particular combination of temperature and pressure can range from

high temperature with no pressure to high pressure with no increase in temperature. #hus,

welding can be accomplished under a wide variety of conditions, and numerous welding

processes have been developed and are used routinely in manufacturing.

'evertheless, the average person has little concept of the importance of welding as a

manufacturing process. If it were not for the use of welding, a large portion of our metal products

would have to be drastically modified, would be considerably more costly, or could not perform

as efficiently. In &'#(, such welding processes that are e;plained below are applied depending

on the desired strength, shape and time.

4.,.1.1. (*"fuel /as 6elding

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In o;yfuel gas welding, acetylene +2)24 is used as fuel. " flame is directed towards the welding

point. #he metals to be joined are melted at their joints during the process. &sually, materials are

thinner than 2mm are welded by this process. ?ostly brass, silver and copper are welded by this

methodF however iron can also be welded.

4.,.1.2. Arc 6elding

In arc welding, both the electrode and the workpiece become part of an electric circuit. #his

circuit causes an arc flow between the electrode and the work. #his arc melts metals during

welding.

4.,.1.2.1. Shielded Metal Arc 6elding @SMA6

(hielded metal arc welding is performed by striking an arc between a coatedmetal electrode and

the base metal. Ence the arc has been established, the molten metal from the tip of the electrode

flows together with the molten metal from the edges of the base metal to forma sound joint. #his

process is known as fusion. #he coating from the electrode forms a covering over

the weld deposit, shielding it from contaminationF therefore the process is called (?">.

#he main advantages of shielded metal arc welding are that high!uality welds are made rapidly

at a low cost.

It is the most common arc welding process used in &'#( because of its low cost and wide

versatility. It provided a protective atmosphere and stabilizes the arc. #hese were the main

problems of early efforts of arc welding. ?oreover, (?"> provides a protective coating to slow

the cooling of welding and prevent the o;idation. "t the same time (?"> provides very good

penetration in welding process and used most commonly in thick metal plates.

4.,.1.2.2. /as Tungsten Arc 6elding @/TA6

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#he primary difference between shielded metal arc welding and gas tungsten arc welding is the

type of shielding used. In gas tungsten arc welding, both the arc and the molten puddle are

covered by a shield of inert gas. #he shield of inert gas prevents atmospheric

contamination, thereby producing a better weld. #he primary gases used for this process are

helium, argon, or carbon dio;ide. In some instances, a mi;ture of these gases is used .

4.,.1.2.,. /as Metal Arc 6elding @/MA6

Das metal arc welding D?">4, formerly known as ?ID welding for metal inertgas4, was a

logical outgrowth of gas tungsten arc welding. #he process is similar, but the arc is now

maintained between the workpiece and an automatically fed, consumable wire electrode.

"rgon, helium, and mi;tures of the two can be used for welding virtually any metal, they areused primarily with the nonferrous metals. In welding steel, some E 2or +E2is usually added to

improve the arc stability and reduce weld spatter. #he cheaper +E2can be used alone in welding

steel, provided that a deo;idizing electrode wire is employed.

#he specific shielding gases can have considerable effect on the nature of metal transfer from the

electrode to the work and also affect the heat transfer behavior, penetration, and tendency for

undercutting weld pool e;tending laterally beneath the surface of the base metal4. (everal types

of electronic controls can be used to alter the waveform of the current. #his makes it possible to

control the mechanism of metal transfer, from drops, to spray, to shortcircuiting drops. (ome of

these variations include pulsed arc welding D?">B4, shortcircuiting arc welding D?">(4,

and spray transfer welding D?">(#4. :uried arc welding D?">:4 is another variation in

which carbon dio;iderich gas is used and the arc is buried in its own crater.

Das metal arc welding is fast and economical because there is no fre!uent changing of electrodes,

as with sticktype electrodes. In addition, there is no slag formed over the weld, the process canbe readily automated, and, if done manually, the welding head is relatively light and compact. "

reversepolarity $+ arc is generally used because of its deep penetrated, spray transfer, and

smooth welds with good profile. Brocess variables include type of current, current magnitude,

shielding gas, type of metal transfer, electrode diameter, electrode composition, electrode stickout

e;tension beyond the gun4, welding speed, welding voltage, and arc length.

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4.4. Surface Treatment and Finishing 0rocesses

4.4.1. Sand lasting

(and blasting is a method for giving glass surfaces a matt finish either for decoration or to reduce

transparency. #he method was invented in 15- by an "merican, :enjamin +. #ilghman, who is

thought to have been inspired by the effect of sand being blown against windows on the"merican prairies. +ompressed air forces the abrasive material through the nozzle of a

sandblasting gun and onto the glass surface. "lthough sand can be used, more effective abrasives

with less to;ic effects are now available. (ilicon carbide is commonly used, as is electro

corundum aluminum o;ide4. #he glass is normally placed inside a special cabinet with arm

holes, a viewing window and dust e;traction facilities.

Inputs of the plant Brofile materials, steel plates, steel pipes and machine production, rarely

casting materials4 enter presand blasting machines where in materials entering area. #here are

three sandblasting machines in here. =actory inputs are shotblasted by spherical grid grains

bigger than main sand blasting grains which are applied before painting the materials. :ut this

factory is using steel shots with same size and !uality in pre and final sand blasting. (teel plates

which will are blasted are carried with magnetic and winches to sand blasting machine area.

In &'#(, plates which have width up to 17 mm and thickness up to % mm are being blasted

in horizontal machine. #his machine has 3 mm height. Blates other than this size are blasted in

perpendicular sand blasting machine. If the perpendicular sand blasting machine is used,

hydraulic lifting apparatus are lifting plates to perpendicular position. Blates which have

thickness are less than 1 mm is bent in perpendicular position. #herefore, these plates are being

blasted also horizontal position.

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Brofiles and pipes are being preblasted after than cutting and drilling operations in horizontal

machines, generally. #hese factory inputs are carried with ceiling lifting winches and crosses to

preblasting area.

"vailable machines can not blast profile0pipe which is bigger than 7mm height0diameter and

plate which has width is more than 27 mm. #hese materials are transmitted to manufacturing

area without any blasting operations.

En the other hand, final blasting of the work piece enables the painting well by getting surface

roughness on specific values. #herefore, painting materials wear and adhere to the surface of the

work piece.

4.4.2. eat Treatment

)eat #reatment is the controlled heating and cooling of metals to alter their physical and

mechanical properties without changing the product shape. )eat treatment is sometimes done

inadvertently due to manufacturing processes that either heat or cool the metal such as welding or

forming.

)eat #reatment is often associated with increasing the strength of material, but it can also be used

to alter certain manufacturability objectives such as improve machining, improve formability,

restore ductility after a cold working operation. #hus, it is a very enabling manufacturing process

that can not only help other manufacturing process, but can also improve product performance by

increasing strength or other desirable characteristics.

(teels are particularly suitable for heat treatment, since they respond well to heat treatment andthe commercial use of steels e;ceeds that of any other material. (teels are heat treated for one of

the following reasonsA

(oftening

)ardening

?aterial modification

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In addition to this, &I beams that are constructed in &'#( can de curved or bended after the

welding because of non homogeneous heat distribution. "nd some wrong dimensions appear as a

result of these. =or this reason, with portable o;ygen welding machine, annealing and material

modification is applied these beams.

4.4.2.1. Annealing 0rocess

#he term annealing refers to a heat treatment in which a material is e;posed to an elevated

temperature for an e;tended time period and then slowly cooled. Erdinarily, annealing is carried

out to 14 relieve stressesF 24 increase softness, ductility, and toughnessF and0or 34 produce a

specific microstructure.Brocess annealing is a heat treatment that is used to negate the effects of cold work, that is, to

soften and increase the ductility of a previously strainhardened metal.

5. (M0&TE- N&ME-AL (NT-(L

"ltering the operating procedures of early '+ systems re!uired changing the hardware of the

machine tool itself. In the 18-s +'+ systems, controlled by dedicated mini or microcomputers,

were developed to enable machine tools to be readily adapted to different jobs by altering the

control program, or software. +onse!uently, +'+ machine tools are easier to operate and more

versatile than their '+ counterparts, and their programming is simpler and can be rapidly tested.

+'+ systems can be used with a wide range of machine tools such as milling machines and

lathes. (ome simulate tool movements, while others produce threedimensional views of

components.

In &'#( bending, plasma cutting and shearing machines are +'+ based. ?any are e!uipped

with graphic displays that plot the shapes of the components being machined. #echnical drawing

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workshop gives the code of the workpiece which is being drilled or cut. In contrary to '+

machines, since they have less control hardware, they are cheaper to maintain and are generally

more accurate.

#. (0E-AT(N SE8&ENES (F S(ME 0A-TS

#.1. Flag+

1 " plate is sheared in the proper dimensions with Blasma +utting ?achine.

2 Biercing is done with +'+ Bunching ?achine.

3 Drinding is done.

4 #he piece is shot blasted.

5 It is galvanized.

6 #hen it is painted.

7 "fter this the piece is sent to the furnace heat treated and dried, so the operation is

completed.

#.2. eam+

1 " plate is again cutted into three proper parts with +'+ =lame +utting ?achine.

2 #hese parts are sent to the >elded I:eam ?anufacturing @ine.

3 (urface grinding is done.

4 #he piece is shot blasted.

5 It is galvanized.

6 #hen painted.

7 #he I:eam is sent to the furnace heat treated and dried, so the production of this piece is

completed.

#.,. 6elded 0latform+

1 " plate is again cutted into twelve pieces with proper dimensions with +'+ )ydraulic+utting ?achine.

2 #hese pieces are carried to welding department and welded together with (hilded ?etal

"rc >elding ?achine.


4 #he platform is sent to shot blasting.

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5 #hen it is galvanized.

6 Bainted.

7 "fter this operation it is sent to the furnace heat treated and dried, production is completed.

#.4. ?oint 0art+

1 " plate is sheared in proper dimensions with Duillotine +utting ?achine.

2 =our drills are created by &niversal $rilling ?achine.

3 #he workpiece is bended by 8Q with "bcant )ydraulic Bress ?achineA

4 Drinding is done.

5 (hot blasting is done.

6 #he workpice is painted.

7 #hen sent to furnace heat treated and dried, so the operation is completed.

#.5. ombined eam 0latform+

1 =irst a plate is cutted into seven proper parts with Duillotine +utting ?achine.

2 #hese parts are welded together to form a @(haped construction part.

3 =our drills with 1 mm diameters are created on the seventh part.

4 #he seventh part is welded to the bottom of the short part of the @(haped construction

element with "rc >elding ?achine.


6 #hen the +ombined I:eam Blatform is sent to the (hot :lasting.

7 Dalvanization is done.

8 #he construction part is painted.

9 It is sent to the furnace and so the production of this part is completed.

'. (ST ANALBS F(- (NE (SEN 0A-T+

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FAN(L -( (0 2C,C,5

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11 Dround screw 1 1 cent12 Dround washer 1 1 cent13 Dround washer 1 1 cent1% /ivet 2 17 cent17 Draund label 2 6 cent16 +ardboard bo; 1 2,2S1- (troke keeper % 3S15 (tample 5 7S18 lectric label 1 1cent2 =ancoil filter 1 7S21 +ark 1 6cent22 +ondenser frier 1 2S23 +ondenser frier ins.tape 1 1S2% #op stick sheet 1 2S27 Internal side under ins.tape 2 8 cent26 :/IE 11 filter spring 2 6 cent2- =rontunder sheet 1 2S

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44/47

T#%a1 $#+% #' $h#+en par% &+ 46y%1

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S$a1e pr&$e2,,y%1

>. (NL&S(N

#he summer practice program has a big importance for mechanical engineering third year

students. " manufacturing company was entirely observed during this summer practice and of

some theoretical and practical knowledge about engineering drawing and production techni!ues

from the courses ? 113, ? 11%, ? 23, ? 217 and ?216 which are given in the first and

second years was improved with practical applications. "lso, an e;perience is gained in the real

working life. (tudents become more familiar with working conditions of a company.

@ots of beneficial knowledge is learned by the students. =irstly, students met with a lot of new

systems. >orking principles, production procedures and importance of these steps are learned.

#he systems of some uni!ue and modern production techni!ues such as +'+ operations were

carefully e;amined. #he production steps of special parts were e;amined and the shortest and the

most economical way are learned. #he general location of each production unit and the efficiency

of processes e;amined. #he main differences between the modern and traditional manufacturing

techni!ues are practiced. #hese new systems provide students a researching and improving view.

#he importance of engineering details was learned. #he importance of technical drawings and

graphical representation were understood. ?oreover, during this summer practice program

students improved their ?( Effice and "uto+"$ knowledge.

In conclusion, &'#( is a generally suitable company for ? 288 summer practice. ngineers

has usually good working conditions while workers have not that much. :esides, safety is

sometimes neglected by the workers. when the summer practice, four workers accident happened.

=or better efficiency, &'#( should give more attention to systematic working and planning."lso, there should be more controlling systems that are very important for decreasing operation

time of products.

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