introduction to casting defects

7/21/2019 Introduction to casting defects

http://slidepdf.com/reader/full/introduction-to-casting-defects 1/234

ITC



Some basics - you had in Foundry

Sand casting.Sand castin

g.Steps:

» 1.Mechanical Drawing of the part

» 2. Making pattern- about pattern material.

» 3.Making cores- if needed

» .!reparing drag and cope. "Setting the core# positioning etc.$

» %.&emo'al of pattern

» ()ssembling cope and drag

» *.!ouring- factors# method# etc.» +.,asting remo'ed

» .rimming etc.

» 1/. &0)D F& S4!M05

ITC



1.Mechanical Drawing of the part

2. Making pattern- about pattern

material.

3.Making cores- if needed

.!reparing drag and cope.

"Setting the core# positioning etc.$

%.&emo'al of pattern

()ssembling cope and drag

*.!ouring- factors# method# etc.

+.,asting remo'ed

Some basics you had

in Foundry

1

4a

32

5b 6 8&9 10

5a4b

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,)S456,)S456 F75D)M05)8SF75D)M05)8S

9asically in'ol'es

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45F8705,0 S4=0# S)!0# 754F&M4 F 0 6&)45S F&M0D#

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• ii. )llow it to cool 0) &)5SF0& D7&456 S84D4F4,)45

• iii. &emo'e from the mold 45F8705,0 F 0 !0 F M78D M)0&4)8

•

SIMILARITY WITH POURING CAKE MIX INTO A PAN SIMILARITY WITH POURING CAKE MIX INTO A PAN

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(CASTING OF PLASTICS & CERAMICS - DIFFERENT)

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<nowledge of certain fundamental relationships

is essential to produce good Auality economic

castings

his knowledge helps in establishing propertechniAues for mould design and casting practice.

,astings must be free from defects# must meet the

reAuired strength# dimensional accuracy# surfacefinish

ITC


http://slidepdf.com/reader/full/introduction-to-casting-defects 7/234 utline of production steps in a typical sand casting operation

- pattern making

- ,ore making

- 6ating system

Moulding

Sand Mould

Melting !ouring casting eat reat ,lean 4nspect

Furnaces Solidification Shakeout )ddl. eat reatment

Defects# pressure tightness# dimensions

ITC



)D;)5)60S F ,)S456 !&,0SS• !rocess is cheap

• More suitable for mass production

• Most suitable for manufacturingcompleBCcomplicatedCintricate shaped products.

• 8arge parts weighing se'eral tonnes and also smallcomponents weighing a few grams can be cast.

• 5o limitation on the sie of component.

• Directional properties absent in castings. ,omponents withuniform properties as well as with 'arying properties atdifferent locations can be cast.

• 9y use of cores# sa'ing in machining of holes achie'ed.• 4nternal stresses are relie'ed during solidification in many

types of castings.

• 0'en some materials which cannot be made by otherprocesses made by castingE eg. !hosphor-9rone.

5 4 .

, ) 8 4 , 7 .

ITC



D4S)D;)5)60S

• ,ast product properties inferior in many

cases when compared with other

manufacturing processes.

• 0le'ated temperature working in

castings# as material has to be melted.

• hin section limitations eBist.

•For number of components 'ery small#casting not preferred.

5 4 .

, ) 8 4 , 7 .

ITC



SIGNIFICANT FACTORS-

•TYPE OF METAL,

•THERMAL PROPERTIES OF BOTH THE METAL

AND MOULD,

• GEOMETRIC RELATIONSHIP BETWEEN THE

VOLUME AND SURFACE AREA ,AND

•SHAPE OF MOULD.

ITC



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• 0S0 0;05S 6&0)8 45F8705,0

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Latent heat of

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FOR PURE METALS FOR PURE METALS ::

At the mould walls, metal cools ap!dl"# $oducessol!d!%!ed skin or shell "thickness depends oncomposition# mould temperature# mould sie and

shape etc$• &hese o% e'u!a(ed stuctue#

• Ga!)s *ow oppos!te to heat ta)s%e thou*h the mould

• &hese ae colum)a *a!)s

• +!!)* %oce o% the heat ta)s%e !s educed awa" %omthe mould walls a)d loc.!)* at the a(!s pee)ts %uthe*owth



Solidified structures of metal -Solidified structures of metal -

solidified in a sAuare mouldsolidified in a sAuare mould

/a$. !ure metal

"b$. Solid solution

"c$. :hen thermal gradient is absentwithin solidifying metal

De+el$2%e*! $( " 2e(ee !e7!ueDe+el$2%e*! $( " 2e(ee !e7!ue

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"b$. eAuiaBed dendritic

"c$. eAuiaBed nondendritic



Sie and distribution of the o'erall grain structure throughout

a casting depends on rate ? direction of heat flow

"6rain sie influences strength# ductility# properties along

different directions etc.$

,5;0,45- TEMPERATURE GRADIENTS DUE TO

DIFFERNCES IN THE DENSITY OF MOLTEN METAL AT DIFFERENT

TEMPERATURES WITHIN THE FLUID - S&568 0FF0,S

0 6&)45 S4=0. ITC



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!) the da* hal% o% %las.

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mould, oll da* oe,

appl" pat!)* sa)d, place

the cope hal% o% patte)

a)d %las., am a)d st!.eo%% e(cess sa)d

4# Sepaate %las.s, emoe

patte)s, cut spue, set

coe !) place, close %las.

5# Now a%te clamp!)*,ead" %o pou!)*#

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volume

References - !" Te#t $hapter %&' $hastains !oundry manual ol *, +oogle

• E?/>1 - /Fee3e P$i*! R"!i$1 S!eel

@.;<5-. ;.8

The constants are from experiments and

are empirical



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• 1 A 2 A 4

•1 A 3 A 3

• 1 A 4 A 4

• 1 A 4 A 6



• $ -cp)o$ )' $o% )$ C.a'a)$ :). a 1 A 8 A 6ra)o o pro!o %ro'' capur )$ . ru$$r'/'! o< ro,pac ca')$'

• . Co$)$u)/ E*ua)o$ )' ')!p#)<)% :). .u' o< ra)o' a' . ;#oc)/ )' )$;r'#/propor)o$a# b:$ a$/ 2 a%ac$ ra)o;a#u' ) A L *ua' o a$ )$cra' )$;#oc)/ :.)# a L A *ua' o a %rop )$;#oc)/

• La!)$ar F#o: )' .ar%r o co$ro# a a .).;#oc)/ .a$ a r#a);#/ #o:r ;#oc)/

• C.a'a)$' Vo# 2 .a' !uc. !or !a.!a)ca#-pr'')o$' a$% ca#cu#a)o$'



PURE METALS PURE METALS -

a'e clearly defined meltingCfreeing point#

solidifies at a constant temperature.

0gE )l - ((//,#

Fe - 1%3*/,#

and :- 31//,.

ITC



Solidified structures of metal -Solidified structures of metal -

solidified in a sAuare mouldsolidified in a sAuare mould

/a$. !ure metal

"b$. Solid solution

"c$. :hen thermal gradient is absentwithin solidifying metal

De+el$2%e*! $( " 2e(ee !e7!ueDe+el$2%e*! $( " 2e(ee !e7!ue

- "! " $$l %$ul )"ll.- "! " $$l %$ul )"ll.

A hill 3$*e l$#e !$ !he )"ll "*

!he* " $lu%*" 3$*e ")"5 ($%

!he %$ul

Thee 6"#i !52e# $( "#! #!u!ue#-

"a$. ,olumnar dendritic

"b$. eAuiaBed dendritic

"c$. eAuiaBed nondendritic



S&7,7&0FOR PURE METALS FOR PURE METALS ::

At the mould walls, metal cools ap!dl"# $oducessol!d!%!ed skin or shell "thickness depends on composition# mould

temperature# mould sie and shape etc$

• &hese ae o% e'u!a(ed stuctue#

• Ga!)s *ow oppos!te to heat ta)s%e thou*h the mould

• &hese ae colum)a *a!)s

• +!!)* %oce o% the heat ta)s%e !s educed awa" %omthe mould walls a)d loc.!)* at the a(!s pee)ts %uthe*owth

ITC



Sie and distribution of the o'erall grain structure throughout

a casting depends on rate ? direction of heat flow

"6rain sie influences strength# ductility# properties along

different directions etc.$

,5;0,45- TEMPERATURE GRADIENTS DUE TO

DIFFERNCES IN THE DENSITY OF MOLTEN METAL AT DIFFERENT

TEMPERATURES WITHIN THE FLUID - S&568 0FF0,S

0 6&)45 S4=0.ITC



F& )88SE

• Allo"s sol!d!%" oe a a)*e o% tempeatues

• 6e*!)s whe) temp# dops elow l!'u!dous, completedwhe) !t eaches sol!dous#

• 7!th!) th!s tempeatue a)*e, mushy ! "#s$y state/Stuctue as !) %!*ue8

• I))e 9o)e ca) e e(te)ded thou*hout " add!)* acatal"st#- sod!um, !smuth, tellu!um, 1*

/or by eliminating thermal gradient# i.e. eliminatingcon'ection. "0Bpts in space to see the effect of lack ofgra'ity in eliminating con'ection$

(!%!%sh '%'!$* +!,$h- !#*h%s $!%%. $%!/*0. %#*h'%'!$% '%1%/"s u!m *m"s$. %$*)

ITC



S84D4F4,)45 4M0S84D4F4,)45 4M0

During solidification# thin solidified

skin begins to form at the cool mouldwalls.

hickness increases with time. ITC



,;&45;HS &780solidification time "t$ is a function of 'olume of

the casting and its surface area

t J , " 'olumeC surface area $2

, is a constant Kdepends on mould material# metalproperties including latent heat# temperatureL

) large sphere solidifies and cools at a much slower rate

than a small diameter sphere. "0g- potatoes# one big andITC

Solidification time for 'arious shapesSolidification time for 'arious sha

pesEE



Solidification time for 'arious shapesSolidification time for 'arious shapesEE

0gE hree pieces cast with the S)M0 'olume# but different shapes.

"i$Sphere# "ii$,ube# "iii$,ylinder with height J diameter.

:hich piece solidifies the fastest

SolutionE Solidification time J , "'olumeCsurface area$2

8et 'olume J unity. As 1/um% s s#m%# t J ,C surface area2.

,ylinderE ; J Nr2

h J 2 N r3F

ie# r J "1C2 N$1C3

) J 2 Nr2 O 2Nrh J ( Nr2 J %.%.

hen# t cube J /./2+, t cylinder J /./33, t sphereJ /./3,

M%$#/ "u!%' $ *u% sh#"%' mu/' s/'%s $h% #s$%s$2

SphereE ;J C3 "N r3$ i.e. r J "3C N$1C3

)J N r2 J N "3C N$1C3 J .+

,ubeE ; J a3 ie a J 1 ) J ( a2 J (.

ITC



S&45<)60 )5D !&S4S&45<)60 )5D !&S4

M0)8S S&45<",5&),$ D7&456

S84D4F4,)45

- ,)7S0S D4M05S45)8 ,)560S

80)D456 ,05&0 8450 S&45<)60# !&S4#

,&),<456

ITC

S&45<)60 D70 E



&

&!me

0

2

3

ITC

S&45<)60 D70 E

"1$.,5&),45 F

M805 M0)8 )S 4

,8S !&4&

S84D4F4,)45

"2$ ,5&),45 F

S84D4F456 M0)8#

8)05 0) F

F7S45

"3$ ,5&),45 F

S84D4F40D M0)8D7&456 D&!

)M9405 0M!

7 F 0S0# 8)&60S S&45<)60 D7&4567 F 0S0# 8)&60S S&45<)60 D7&456

,8456 F ,)S456,8456 F ,)S456 "40M 3$ %+3"u!% m%$#/



S84D4F4,)45 ,5&),45 F& ;)&47S M0)8SS84D4F4,)45 ,5&),45 F& ;)&47S M0)8S

M0)8 ;olumetric Solidification ,ontraction

)l (.(

6rey cast 4ron 0Bpansion 2.%

,arbon Steel 2.% to 3

,opper .

Magnesium .2

=inc (.%

ITC



• $OROSI& +UE &O S;RIN<AGE O= GASESAN+ 1E&AL &OO#

RELA&E+ &O +UC&ILI&

AN+ SUR=ACE =INIS;

/+UC&ILI& V>S $OROSI& CURVES =OR

+I==EREN& 1E&ALS8- ELI1INA&ION 6 VARIOUS 1EANS

/A+E?UA&E SU$$L O= LI?UI+ 1E&AL, USE O=C;ILLS, NARRO7ING 1US; @ONE- ,)S456S79P0,0D 4SS)4, !&0SS456

ITC



!&S4 9 6)S0S!&S4 9 6)S0S

84I74D M0)8S );0 46 S879484 F&

6)S0S

D4SS8;0D 6)S0S 0>!0880D F&M

S8745 D7&456 S84D4F4,)45

"ydrogen# 5itrogen mainly$),,7M78)0 45 &0645S F 0>4S456

!&S4 & ITC



0ffect of microporosity on the ductility of Auenched and

tempered cast steel Q !orosity affects the Rpressure tightnessH of

cast pressure 'essel

D u c t i l i t y

!orosity"$

0longation

&eduction of area

/ % 1/ 1%

ITC

) SF8: F M805 M0)8 45 M78DS



F8: F M805 M0)8 45 M78DSF8: F M805 M0)8 45 M78DS4mportantE pouring basin# mould ca'ity ? riser

6)456 SS0M Design -fluid flow# heat transfer# influence of temperature gradient#

F874D F8::ithout turbulence

or with minimied turbulence

0) F8: 45F8705,0D 9 M)5 F),&S

F874D4-A chaacte!st!c elated to 'iscosity#

0S F F874D4 - 7S456 ) S!4&)8 M78D.Fluidity 4ndeB

ITC



0S F&

F874D4

7S456 ) S!4&)8

M78D.

F874D4 45D0> 4S

0 8056 F0 S84D4F40D

M0)8 45 0

S!4&)8 !)SS)60#

6&0)0& 0

8056# 6&0)0&

0 F874D4

45D0>.



$A&&ERN$A&&ERN

• 1odel o% a cast!)* co)stucted such that !t

%oms a) !mpess!o) !) mould!)* sa)d

ITC



!)0&5!)0&5

• 0st

step- $epae model /patte)8 +!%%es %om the cast!)*

+!%%ee)ces $atte) Allowa)ces#

• &o compe)sate %o metal sh!).a*e,• $o!de su%%!c!e)t metal %o mach!)!)*

• Eas!)ess !) mould!)*

• )s Shrinkage allowance# Draft allowance# Finishing allowance#

Distortion or camber allowance#Shaking or rapping allowance

ITC



M)0&4)8M)0&4)81. :D.

2. M0)8 )l# ,4# 9rass#

3. For special casting processes# !olystyrene which lea'es mould as gas when heated also used. Ty"%s- m#y

Simple-4dentical patterns

,ompleB# intricate- with number of pieces. Single or loose piece Split gated Match !late

Sweep Segmental Skeleton"frame# ribbed$# skell

9oBed 7p dd shaped etc. Sketches-- ITC



M#$%!#/ M#$%!#/ 1. :D.

/8 ,heap# easily a'ailable# light# easiness in surfacing# preser'ing "by shellac coating$# workable# ease in Toining# fabrication

/-8 Moisture effects# wear by sand abrasion# warp during forming# not f or rough use#

Must be properly driedC seasoned#

free from knots# straight grained

0gs. 9urma teak# pine wood# mahogany# Sal# Deodar# Shisham# :alnut# )pple tree

ITC



2# M0)8E

For durability# strength

0gsE )l alloys# 9rass# Mg alloys# Steel# cast 4ron for

mass production

"first# wooden pattern is made# then cast in the metal$

ype of material depends on shape# sie# number of

castings reAuired# method of moulding etc.

ITC

!0S F !)0&5S



!0S F !)0&5S

1. S45680 !40,0 !)0&5.

5 4 .

, ) 8 4 , 7 .

ITC



2. S!84 !)0&5 ": !40,0 8

5 4 .

, ) 8 4 , 7 .

ITC



2. a# &00 !40,0 S!84 !)0&5

5 4 .

, ) 8 4 , 7 .

ITC

3 8S0 !40,0 !)0&5



3. 8S0 !40,0 !)0&5

5 4 .

, ) 8 4 , 7 .

ITC



. ,!0 )5D D&)6 !)0&5

• COPE AND DRAG PARTS OF THE PATTERN MOUNTED ON SEPARATE PLATES2

• COPE HALF AND DRAG HALF MADE 4YWORKING ON DIFFERENT MOULDING

MACHINES2• THIS REDUCES THE SEPARATE COPE AND DRAG

PLATE PREPARATION2

• GENERALLY FOR HIGH SPEED MECHANISED MOULDING .

5 4 .

, ) 8 4 , 7 .

ITC



%. M), !8)0 !)0&5 B $atte) *e)eall" o% metal a)d plate ma.!)*

pat!)* l!)e metal>wood#

5 4 .

, ) 8 4 , 7 .

ITC



(. F88: 9)&D !)0&5.

=o th!) sect!o)s#

5 4 .

, ) 8 4 , 7 .

ITC

THIN PATTERN



*. 6)0D !)0&5 -

Gat!)* s"stem !s a pat o% the patte)#

5 4 .

, ) 8 4 , 7 .

ITC



+. S:00! !)0&5 Q=o la*e s!9e cast!)*s !) small )umes# &emplate o%

wood attached to a sweep used#

5 4 .

, ) 8 4 , 7 .

ITC



. S06M05)8 !)0&5 Q

=o !)*s, wheel !ms, la*e s!9e *eas#

5 4 .

, ) 8 4 , 7 .

ITC



1/. S<0805 !)0&5#-St!c.le oad used to scape the e(cess sa)d#

0g. il pipes# water pipes# pipe bends# boBes# 'al'e bodies etc#

5 4 .

, ) 8 4 , 7 .

St!c.le oad

ITC



11. S088 !)0&5

5 4 .

, ) 8 4 , 7 .

ITC



12. 9748 7! !)0&5 QAlso called la**ed up patte)s- =o aels, p!pes,

colum)s etc

5 4 .

, ) 8 4 , 7 .

ITC



13. 80F )5D &46 !)0&5 Q

=o pats to e made !) pa!s#E*: le*s o% sew!)* mach!)e, wood wo.!)* lathe,

*ade) e)ches, ha)*es %o sha%ts, ac.ets %o

lu**a*e ac.s etc#

5 4 .

, ) 8 4 , 7 .

ITC



• ype of pattern depends onE

• Shape and sie of casting#• number of castings reAuired#

• method of moulding employed#

• easiness or difficulties of the mouldingoperations#

• other factors peculiar to the casting#

5 4 .

, ) 8 4 , 7 .

ITC



,)&),0&4S4,S F

!)0&5 M)0&4)8S,)&),0&4S4, &)456

7OO+ AL S&EEL $LAS&IC CAS& IRON

M),45)9484 0 6 F 6 6

:0)& &0S4S)5,0 ! 6 0 F 0

S&056 0 6 0 6 6

:046 0 6 ! 6 !

&0!)4&)9484 0 ! 6 F 6

&0S4S)5,0 :

• CORROSION (y ,#$%!) 0 0 ! 0 !

• SWELLING ! 0 0 0 0

0- 0Bcellent 6- 6ood F-fair# !- !oor

ITC



Functions of pattern

• Moulding the 6ating system

• 0stablishing a parting 8ine#

• Making ,ores#• Minimising casting Defects#

• !ro'iding 0conomy in moulding

• thers# as needed



M78D456 S)5D

• 6ranular particles from the breakdown of rocks by frost# wind# heat and water currents

• ,ompleB ,omposition in different places

• )t bottom and banks of ri'ers

• - mainly silica "+( to /$ )lumina " to + $

4ron oBide "2 to %$ with oBides of i# Mn# ,a. etc#

ITC



5)7&)8 S)5D , called 6reen sand. nly water as binder can maintain water for long time

S504, S)5D#- /1$6&005 and "2$D& types

"1$ )rtificial sand by miBing clay free sand# binder"water and bentonite$

,ontains 5ew silica sand 2% ld sand */

bentonite 1.%moisture 3 to 3.%

/28 New 05D Old F4D

e)to)!te a)d mo!stue #5 D each

ITC



D& S)5D- for moulding large castings. Moulds of green sand dried and baked with 'enting done. )dd- cow dung# horse manure etc.

8)M S)5D- miBture of clay and sand milled with water to thin plastic paste. Mould made on soft bricks. he mould dried 'ery slowly before cast. For large regular shapes-drums# chemical pans etc.

F),456 S)5D- used directly with surface of pattern comes in contact with molten metal must ha'e high strength# refractoriness.

Silica sand and clay without used sand- plumbago powder# ,eylon lead# or graphite used. 8ayer of 2/ to 3/ mm thick---

#u$ 567 $ 587 ,h/% mu/' s#'

ITC



9),<456 S)5D- old used moulding sand called floor sand black in colour. 7sed to fill mould at back of facing layer. :eak in bonding strength

SS0M S)5D- used in machine moulding to fill whole of f lask. Strength# premealibility and refractoriness high

!)&456 S)5D- used for separating boBes from adhering# free from clay

,&0 S)5D- for making cores. Silica sand with core oil "linseed oil# rosin# light mineral oil# binders etc$

S!0,4)84S0D S)5DS - like ,2 sand# Shell sand# etc for special applications

Mould washers- slurry of fine ceramic grains applied on mould surface to minimie fusing

ITC

)b t M78D456 S)5D



)bout M78D456 S)5D

1. 5)7&)8 S)5D2. S504, S)5D.- 6&005 and D&

3. D& S)5D

. 8)M S)5D

%. F),456 S)5D(. 9),<456 S)5D

*. SS0M S)5D

+. !)&456 S)5D

. ,&0 S)5D1/. S!0,4)84S0D S)5DS

11. Mould washers

ITC

M78D456 S)5D !&!0&40S



M78D456 S)5D- !&!0&40S

• 6reen Strength- )deAuate strength after miBing# andplasticity for handling

• Dry Strength- )fter pouring molten metal# adTacent surface

loses water content. Dries. Dry sand must ha'e enough

strength to resist erosion• ot Strength- Strength at ele'ated temperature after

e'aporation of moisture

• !ermeability- !ermeable or porous to permit gases to escape.

)bility of sand moulds to allow the escape of gases

ITC



• hermal stability- &apid eBpansion of sand surface atmould-metal interface. May crack. &esults in defect calledS,)9

• &efractoriness- )bility of sand to withstand hightemperature

• Flowability- )bility to flow ? fill narrow portions aroundpattern

• Surface finish- )bility to produce good surface finish incasting

• ,ollapsibility- )llow easy remo'al of casting from mould

• &eclamation- Should be reusable and reclaimable

ITC



F7&5),0S



F7&5),0S

!roper selection depends onE

• Compos!t!o) a)d melt!)* po!)t o% allo" to e cast• Co)tol o% atmosphe!c co)tam!)at!o)

• Capac!t" a)d ate o% melt!)* e'u!ed

• E)!o)me)tal co)s!deat!o)s- )o!se, pollut!o)

• $owe suppl", aa!la!l!t", cost o% %uels• Eco)om!c co)s!deat!o)s-!)!t!al cost, opeat!)* cost,

ma!)te)a)ce cost etc#

,7!8)S "U %/ # ;0&4,)8# 46 &)0S8

080,&4, F7&5),0S

45D7,45 F7&5),0S

ITC



F75D&40S

• =om Lat!) wod- u'%!% "meaning melting ? pouring$

• !attern ? Mould making- automated# computer integrated

facilities- ,)DC,)M

• Melting# controlling composition ? impurities# pouring-

7se of con'eyors# automated handling# shakeout#

cleaning# heat treatment# inspection# etc.

ITC



CUPOLA



8 CRGE ,,E, 7ONR7,

UN7ER GRVI

EE, FLO OF O G,E,OVING UR7,

CONINUOU, IN OERION

Vr)ca# '# '.## #)$% :). <)r

br)c='Ba' o$ <our '# co#u!$'

)$% %oor' )$ . ba' p#a o

r!o; r')%u a . $% o< !#

)r b#a' .rou. u/r' $u!br o$

')(>

.rou. c.ar)$ %oor co= p))ro$ 'crap & #)! 'o$ c.ar%

Co#% & o b#a' cupo#a'

TOWER FURNACE



O EL LUINIU

& a##o/'

3 !a)$ 'c)o$'

c.ar)$ #;aor

!#)$ u$) .o#%)$

<ur$ac C/#)$%r)ca#

roar/ u$)>

uo!a)c co$ro#'

Gra abo; bur$r'

'uppor' 'o#)% c.ar

o#$ c.ar ru$'

%o:$



REVERBERATORY FURNACE

S%"ll u*i!# /01 ($ %el!i* *$* (e$u# %e!"l#, l"e /"6$u! <T1

; T "2"i!5 !$ %el! i$*

AIR FURNACE4

O*e !52e $( RB- !$ %el! "#! i$* ($ $ll %ill $ll#, %"lle"6le "#!i*#,

; T "2"i!5 K Ch"e $u! $( $*!"! )i!h (uel, le## #ul2hu "6#$6e,

l$* %el!i* !i%e e*"6le# $*!$l $( $%2$#i!i$*, l"e #i3e #"2

h"*le.

Lu%2 $"l, 2ul+ei#e (uel, $il u#e !$ (ie. S$li $"l 6u*! i* " "!e



The Sand Casting Process



he most commonly used ,asting !rocess# in the entire,asting 4ndustry.

• ,onceptE he top and the bottom of the mold form theflask. Vholds the whole thing together.V he cope and thedrag.

•)n impression de'ice# in the middle of the flask assembly#called the pattern.

• he sand around the pattern is called the# holding medium.

• hese are the basic# uni'ersal casting components# which canbe applied to all ,asting and Molding !rocesses.

• he mold maker uses the pattern to make the impression inthe holding medium# the sand# then sets the pattern aside#closes the cope and drag# to complete the flask# and formsthe mold# fills that 'oid with a molten material which couldbe almost anything.

ITC



ITC



Casting a component



ITC

1!ddle suppot %o a !.e ac. o) pul!c ta!)s#



• MaterialE%3% aluminum.

• !rocessE Sand casting.• ,asting SupplierE DentManufacturing# 4nc.#5orthampton# !ennsyl'ania.

• his 2-lb casting replaced fourstainless steel fittings# eliminatingthe need for se'eral nut and boltassemblies.

• he +.% B *.% B 3.%-in. component isdesigned to hold 1.2%-in. steel pipehandrails on a bike rack.

• he foundry polishes and clearanodies the casting for a long-lasting finish# which pro'ides acleaner appearance whencompared to the pre'ious assembly.

• he casting eliminates the need formultiple parts# reducingmanufacturing time and o'erallcost.

ITC

)ir scoop that directs air flow for an agricultural



combine#

MaterialE+/-%%-/( ductile iron.

• !rocessESand casting.

• ,asting SupplierE 5eenah Foundry,o.# 5eenah# :isconsin.

• riginally manufactured as a

stamping and weldment# this 2%-lbcomponent was con'erted to aductile iron casting at a / costreduction. !ictured is the casting"r$ and the pre'iousstampingCweldment "l$.

• he cast component# whichmeasures 21/ B (/ B (2/ mm#

afforded the customer a simplerdesign# eliminating the need forcapital resources and manpowerfor eBtensi'e stamping and weldingeAuipment.

ITC

orAue arm bracket for the after-market automoti'e



industry.

• MaterialE+/-%%-/( ductile iron.

• !rocessE Sand casting.

• ,asting SupplierE Farrar ,orp.#5orwich# <ansas.

• ,on'erted from a fabricated steelassembly# the casting sa'ed thecustomer WCpart due to reducedgrinding and no assembly time forthe component "pre'iously +-1/hours per bracket$.

• Fully machined by the foundry# thecasting achie'es tighterdimensional tolerances than thefabrication and has eBperiencedero returns due to failure in the

field.• 7sing rapid prototyping# the

foundry was able to deli'er sampleparts for appro'al within one weekfrom design deli'ery.

ITC

D40 ,)S456



D40 ,)S456

GRAVI& SE1I $ER1ANEN& 1OUL+& !0&M)505 M78D

,8D ,)M90& ,)M90&

"0)456 ,)M90&$

7S4D0 0 M),4504506&)8 :4 0 M),450

ITC



!0&M)505 M78D& 6&);4 D40 ,)S456

HM0)884, M78DS 7S0D - M78D

:4S)5D 0M!0&)7&0

@5 0>0&5)8 !&0SS7&0 )!!840D#

@D&S)4, !&0SS7&0 9 &4S0&456

@8)M! 98),<C,&0 48 )!!840D D40 S7&F),0S

F& 0)S &0M;)8

@F)S ,5D7,45 &)!4D ,8456

ITC

• $OIN&S



• - ;0& ,8S0 80&)5,0 ,)S456S#

• M&0 S&056# 80SS !&7S

• - 900& S7&F),0 F454S ,M!)&0D

• S)5D ,)S456

• - S7&F),0 F&00 F&M S)5D

• - D05S4 0);

• - M&0 D4M05S45)8 ),,7&), - /./( /.3 MM

• - D40S 80SS ,S8 )5 !&0SS7&0 D40 ,)S456 D40S

• - 6D F& !&0SS7&0 46 ;0SS08S

• - 80SS ,8456 ,&),<S• - 80SS S<488

• - 6D F& 8)&60 I7)5440S

ITC

- !45S



58 F& SM)88 )5DM0D47M S4=0 ,)S456S

F& 55 F0&&7S# M)458

8)&60 I7)54#

97 4D054,)8 !40,0S 58 !& 0856)45

S&0SS )5D S7&F),0 )&D50SS D0F0,S

9S0&;0D

,)S456 90 :4D&):5 ,)&0F788

F&M D40S

ITC

S0M4!0&M)505 D40,)S456



• D40 !&0SS7&0 ) 2/ 2/#/// )M

• !&0SS7&0 F488 S84D4F4,)45

• F& 55F0&&7S M0)8S

• F& 45&4,)0 S)!0S

• ,8S0 80&)5,0S !SS4980

• F& M)SS !&D7,45# U1/#///

ITC



F& S0M4 )5D !&0SS7&0 D40 ,)S456 S0 7!S#

0 F88:456 F),&S ) M7S) M7S

1. ) 6D D40 S0 M0,)54SM

2. M0)5S F& F&,456 M0)8

3. D0;4,0 <00! D40 )8FS !&0SS0D

. )&&)560M05 F&

)7M)4, &0M;)8 F ,&0S- 4F )5ITC

: !0S F !&0SS7&0 D40 ,)S456



,8D ,)M90& -

0)456 ,)M90& 7S4D0 0 M),450

- F& )l# Mg# ,u# )5D 46 M08456 )88S

,)M90& -

0)456 4506&)8 :4 0 )5D8456 6S0 50,< M0,)54SMS :4D08 7S0D

F& 8: M08456 )88S- =n# !b# 0tc.

)8S ;),77M D40 ,)S456 M),450S- S!),0

90:005 0 D40S )5D !)SS)60 ;),77M4S0D90F& !7&456-

S79M0&60D !87560 !0# D4&0, )4& D40,)S456 M),450S

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,05&4F76)8 ,)S456

&70-

F& 88: ,4&,78)&- !4!0S- S)!0

9 ,05&4F76)8 ),45- S!00D F

&)45 4M!&)5

,)5 90 &4=5)8 ;0&4,)8 &

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• S0M4-

• ,05&0 ,&0 F& 4550& S7&F),0-S)!0 9 M78D )5D ,&0#

M)458 5 9 ,05&&4F76)8 ),45-

0gEF8:008S

• S!00D F &)45-

(/ */ 4M0S 6&);4 F& &4=5)8 )5D45,8450D !0S

)9;0 1// F& ;0&4,)8 !0S.

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;),77M D40 ,)S456 M),450S



; ,77 , S 56 , 5 S

• SM0 )4& 05&)!!0D 45 &D45)& D40 ,)S456 M),450S• 4S !&D7,0S 98: 80S

• 45 ;),77M D40 ,)S456 !0# ;),77M !7M! ,&0)0S ;),77M

45 D40 ,);4# ) S0)8 ,7S FF 0 !4!0 ,550,45 )F0&

0;),7)456

• 4S !&0;05S F8: F M0)8 F&M D40 ;),77M !4!0• F8: F M805 I74,< )5D )7M)4,

• F454S0SE• )88 D40 ,)S456S S7S,0!4980 ,&&S45# 05,0

S79P0,0D F454S456 !0&)45S & !8)456

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D0S465 ,5S4D0&)45S



• 7S0 F &49S# 79S# 9SS0S M7S 90 &0D7,0 :046#S&05605 0 !)&# 4M!&;0 0 )!!0)&)5,0

• 4,< S0,45S M)<0 D40 0& )5D 7S 80SS05

D40 84F0

• 8)&60 S0,45S 90 ,80D M) ,)7S0 !&S4

• 0>,0SS4;0 S0,45)8 ,)560S 90 );4D0D

• );4D 75D0&,7S

• F4880S D0S4&)980 ;0& S)&! 0D60S

• D&)FS 500D0D 5 )88 ,)S456S

• 0P0,& !45S ) 9),< );4D ;4S49484 F M)&<S• F8)S 50,0SS)& # 90 &0M;0D 8)0& 9

&4MM456

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D40 M)0&4)8S



D40 M)0&4)8S

,)S456 )88S D40 M)0&4)8

45# 80)D )88 CAST STEEL WITHOUT HEAT

TREATME T

=45,# )l HEAT TREATED LOW ALLOY STEEL

,!!0& 9)S0)88S

HEAT TREATED SPECIAL ALLOY

STEEL

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+IE CAS&ING ALLOS



+IE CAS&ING ALLOS

• M)458 55-F0&&7S ,)S456S :4!&!0&40S ,M!)&)980 :4 F&6456S

=45, )88SE- :4D08 7S0D " */$- )l .1 ,u

M)> 1# Mg /. 9)8)5,0 =45,

• -- !0&M4S 8560& D40 84F0# S45,0 0M!. 4S 8:

• 6D S&056# ensile StrengthE 3// <gCcm2

• ;0& 6D F874D4# 7S 45 S0,45S !SS4980

• 7S0S7S0SE )7M9480S# 48 97&50&S# F&4D60S# &)D4# ;,M!505S# M),450 8S# FF4,0 M),450&40S

ITC

)87M4547M )88S:



• 9 ,8D ,)M90& !&,0SS-

• ,u 3 to 3.%# Si % to 11 # 9)8)5,0 )l.

• 8460S )88S# 6D ,&&S45

&0S4S)5,0# F450 6&)450D S&7,7&0D70 ,488456 0FF0,

• ensile StrengthE 12%/ to 2%// <gCcm2

• 6D M),45)9484# S7&F),0 F454S

• 7S0S7S0SE M),450 !)&S# )7M4;0#

7S0 8D )!!84)5,0S 0,.

ITC

,!!0& 9)S0D )88SE



• ,u %* to +1=n 1% to / SM)88 I7)5440SF Si# !b# Sn

• ;0& 46 05S480 S&056E 3*// to

(*//<gCcm2F

• 6D ,&&S45 &0S4S)5,0 :0)&&0S4S)5,0

• 8: F874D4# 05,0 &0D7,0D D40 84F0

• 7S0S7S0S 080,&4,)8 M),450& !)&S#

SM)8860)&S# M)&450# )7M4;0 )5D )4&

,&)F F4456S# )&D:)&0S

ITC

M)650S47M 9)S0D )88S:• 8460S 45 D40 ,)S456# !&D7,45 ,S S8468



8460S 45 D40 ,)S456# !&D7,45 ,S S846846# )lE =nE /.% MnE /.% SiE /.%# ,uE/.3&0M)45456 Mg.

• 7S0S7S0SE 45 )4&,&)F 45D7S&# M& ? 4S&7M05 !)&S#!&)980 8S# 7S0 8D )!!84)5,0S

80)D ? 45 9)S0D )88S

• 8ead baseE +/ !b ? in base *% tin#

antimony# copper

• 84M40D )!!84,)45S.84M40D )!!84,)45S. 846 D7 90)&456S# 9)0&!)&S# >-&) S408DS# 8: ,S P0:0880&# 55-,&&S4;0 )!!84,)45S

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• !&D7,45 F )88 :008S

• M0D F !&D7,45 COUN&ER

$RESSURE +IE CAS&ING

•

• The manufacturing process commenceswith the smelting of pure aluminium

ingots in a 5-ton basin type furnace.

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ITC



• The furnace is a dry sole type furnace whosefunction is to smelt the primary rawmaterial, and reprocess alloy scrapsconsisting of:- wheels used in destructive

testing by the quality control department,and the risers and gates removed from thewheels following the casting process. Fromthe dry sole furnace, the molten aluminiumis transferred to the alloy induction furnacesvia a feed channel to enable the miing andsmelting of the elements required in thepreparation of the alloy ! "l#i $.

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• " spectrometer equipped quality control laboratory isused during the process of alloy preparation to ensurethe composition of the alloy meets the required

specification during this stage of the preparationprocess. #pectrometer analysis sampling is also appliedrandomly to finished wheels.

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• %olten alloy is transferred to holding furnaces foreventual transfer to the casting machines. "fter themolten alloy has been tested for conformance tospecifications it is transported to the alloy treatment



specifications, it is transported to the alloy treatmentstation where the alloy is submitted to three procedures

performed by an automatic process control system. Thetreatment unit introduces salts into the molten alloyusing a high-speed spinner, where the alloy purificationis assisted by the use of nitrogen gas &ets. The threeprocedures to which the molten alloy is submitted are:-

∀ • 'egassing

∀ • (efining

∀ • %odifying

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These processes are intrinsic to the removal of allundesirable impurities in the molten alloy. The automationof these processes improves the product quality control,production rates and importantly minimi)es wastage byreducing the possibilities of re&ection of the finishedproduct. Following the procedures to ensure that themolten alloy conforms to precise specification, it is

transported in holding furnaces to the low pressure castingmachines. These furnaces are designed to produce castingby employing pressurised air within a range of *.+ ! .*atm., the pressuri)ation being monitored and varied by acomputeri)ed process control system according to flow

requirements

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Compute!9ed pocess tech)olo*" automat!call" co)tols the cast!)* pocess, a)d the),

at the e)d o% the 4#5 m!)ute cast!)* c"cle, cools a)d eects the wheel o)to a catche am

des!*)ed %o th!s pupose



des!*)ed %o th!s pupose#

;old!)* %u)aces co)ta!) etwee) 5-J5.* o% molte) allo" - su%%!c!e)t %o up to

appo(# 4 hous o% cast!)* opeat!o)s# 7he) the hold!)* %u)ace !s e(hausted !t !se(cha)*ed %o a %ull eplaceme)t %u)ace us!)* the ta)s%e shuttle - !llustated aoe -

w!thout !)teupt!o) to the cast!)* pocess#

;"daul!c s"stems co)tol ma)" o% the u)!tKs opeat!)* moeme)ts, a)d, due to h!*h

opeat!)* tempeatues ma)" measues hae to e ta.e) to e)ale m!)!m!9at!o) o% !s.

a)d educt!o) o% ma!)te)a)ce o% these s"stems# =o e(ample, !t !s )ecessa" %o all

h"daul!c s"stems to emplo" %!e es!sta)t %lu!ds thee" el!m!)at!)* %!e !s.# L!.ew!se,

all h"daul!c hoses hae to e metal coeed a)d !)sulated a*a!)st acc!de)tal splashes

o% molte) metal#

&he opeatos o% the Cou)te $essue Cast!)* 1ach!)es pe%om a) !)!t!al !sual

'ual!t" co)tol as the wheels ae eected %om each u)!t a)d palleted ead" %o ta)spot

to the R!se cutt!)* depatme)t#At th!s %!st sta*e !) the mach!)!)* pocess %ollow!)* cast!)*, the emoal o% the *ates

a)d !ses !s ca!ed out " automated mach!)es des!*)ed %o th!s pupose B w!th a c"cle

t!me o% 5 seco)ds pe wheel# &he CNC !se-cutt!)* u)!t pe%oms the %ollow!)*

opeat!o)s ITC



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∀ • $e-o!)* o% the ce)tal hole o% the wheel

• Remoal o% the cha))el us coespo)d!)* to the su%ace o!)ts o) the +!eKs

mo!)* pats• &!mm!)* uppe a)d lowe ed*es o% the wheel

• &he wo.!)* c"cle o% the R!se cutt!)* u)!t !s completel" automated to !mpoe oth

'ual!t" co)tol a)d poduct!o) ate pe mach!)e# All waste poducts ae collected %o

ec"cl!)* at the %ou)d"# &he mach!)e opeat!o)s ae pe%omed u)de a suct!o) hood to

emoe alum!)!um dust a)d pat!culates %om the e)!o)me)t !) po(!m!t" to th!s u)!t#

• Customa!l", a%te the mach!)!)* pocesses hae ee) completed o) the )ewl" cast

wheels, the wheels ae passed to the 'ual!t" co)tol u)!t %o e(am!)at!o) u)de a a!et"

o% )o)-destuct!e a)d destuct!e tests# 6atch sampl!)* o% the wheels ma" !)ole

ta.!)* a 0-2mm scape ta.e) us!)* a lathe, a)d u))!)* a spectomete a)al"s!s o% the

esult!)* allo" sample#ITC



• M-Ra" a)al"s!s mach!)e !) ?ual!t" co)tol depatme)t

• No)-destuct!e test!)* !s u)deta.e) us!)* ad!o*aph" pocesses# It !s commo) pact!ce %othe V1 customes to !)clude w!th!) the! co)tactual e'u!eme)ts test!)* olumes a)dt!mescales /!#e# e%oe o a%te mach!)!)*8# &he M-a" co)tol e'u!pme)t ca) e pe-set w!th!)%omat!o) %om up to 0 wheel des!*)s, a)d wheels ca) e !)spected o) a w!de a!et" o%

pos!t!o)s > a)*les /)omall" 2 pos!t!o) a!a)ts8#

• &he wheel ma)!pulato %o ha)dl!)* the wheels du!)* the !)spect!o) c"cle has 5 %ull"compute!9ed a(es a)d a olle co)e"o automat!call" po!des load!)*>u)load!)* o% themach!)e w!th the wheels %o !)spect!o)#

• &he M-Ra" u)!t ta.es 2 wheels at a t!me - o)e !) pocess o% !)spect!o) c"cle, a)d a seco)dwheel !) a hold!)*K pos!t!o)# As the test!)* mach!)e completes the automated !)spect!o) c"cle,!t s!multa)eousl" eects the !)spected wheel, puts the seco)d wheel !)to pos!t!o) %o !)spect!o)

a)d daws a)othe wheel !)to the hold!)*K pos!t!o)# &hus the pe%oma)ce !)spect!o) c"cle !se)ha)ced to !ts ma(!mum poss!!l!t"# +u!)* a) !)spect!o), the opeato mo)!tos the (-a"!ma*e o) a !ew!)* co)sole a)d has the poss!!l!t" o% ma*)!%"!)* the !ma*e o epla"!)*K the

pocess to pec!sel" !de)t!%" a)" cast!)* de%ect e(posed " th!s mach!)e#

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• he neBt stage of the Auality control process is undertaken on 6eometrical

control benches where the physical dimensions of the wheels are compared

with the specification standard using pantographs and micrometers.



• he semi- finished product# ha'ing been submitted to 'arious machining

and Auality control procedures are passed to the finishing dept. which -

dependent upon client specification - either submits the wheels through an

automated paint shop - or polishing line where a bright lacAuer finish has

been specified.

• he finished wheels are then palleted and wrapped in polyethylene film -

ready for transfer to a wheelCtyre assembly plant - prior to final shipment

to the production lines of the ;M customer

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• he palletCboB wrapping eAuipment consists of a motoried wrapping machine Q allowingpallets to be placed on a rotating turntable# and pro'iding film wrapping through thisrotation with a fiBed unit holding the polyethylene roll.



rotation with a fiBed unit holding the polyethylene roll.

• he finished wheels are stored on palletsCboBes until shipping.

•,750& !&0SS7&0 D40 ,)S456 M),450S• he casting machines ha'e e'ol'ed o'er 2% years of de'elopment and manufacturingeBperience of counter-pressure ? low pressure casting machines.

• Simplicity of design# operating con'enience and ease of maintenance are the coreattributes that produce highest le'els of egonomics and safety.

• he abo'e principles are well emphasised by the rugged 'ertical tie-bar constructionincorporating an integral holding furnace.

• he well tried and pro'en technical solutions pro'ide stability# accuracy in guiding andcontrolling the precision of the mo'ing parts# and include essential rigidity# operationaldependability and longe'ity of the machines.

• )ll machines are designed to withstand hea'y-duty ser'ice in foundries operatingcontinuous 2 hour cycles.

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;-!rocess 1. !attern "with 'ent holes$ is placed on hollow carrier

plate.

2. ) heater softens the .//3V to .//*V plastic film.

!lastic has good elasticity and high plastic deformation

i



ratio.

3. Softened film drapes o'er the pattern with 3// to

(// mm g 'acuum acting through the pattern 'entsto draw it tightly around pattern.

. Flask is placed on the film-coated pattern. Flask

walls are also a 'acuum chamber with outlet shown.

%. Flask is filled with fine# dry unbonded sand. Slight

'ibration compacts sand to maBimum bulk density.

(. Sprue cup is formed and the mold surface le'eled.

he back of the mold is co'ered with unheated plasticfilm.

*. ;acuum is applied to flask. )tmospheric pressure

then hardens the sand. :hen the 'acuum is released

on the pattern carrier plate# the mold strips easily.

+. ,ope and drag assembly form a plastic-lined ca'ity.

During pouring# molds are kept under 'acuum.. )fter cooling# the 'acuum is released and free-

flowing sand drops away lea'ing a clean casting# with

no sand lumps. Sand is cooled for reuse.

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9enefits f 7sing he ;-!rocessE

• ;ery Smooth Surface Finish



;ery Smooth Surface Finish

• 12%-1%/ &MS is the norm. ,ast surface of 2// or better# based on Th% A/umum Ass*#$ Am%!*# STD AA-C8-E59.

• 0Bcellent Dimensional )ccuracy

• ypically OC-./1/ up to 1 inch plus OC-.//2 per additional inch. ,ertain details can be heldcloser.

• OC-./1/ across the parting line.

• ,ored areas may reAuire additional tolerances.

• =ero Draft

• 0liminates the need for machining off draft to pro'ide clearance for mating parts andassembly.

• !ro'ides consistent wall thickness for weight reduction and aesthetic appeal.

• )llows for simple fiBturing for machining and inspection.

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• !attern construction becomes more accurate and efficient.

• otal tolerance range becomes more accurate and efficient.



g

• 6eometryCtolerance of part is at its simplest form. Draft does not use up

tolerance.• DesignCdrafting is less compleB. ,alculations and depictions related to draft are

eliminated.

• hin :all Sections

• :alls as low as .1// in some applications are possible.

• 0Bcellent &eproduction f Details• ;ery small features and lettering are possible.

• ,onsistent Iuality

• )ll molding is semi-automatic. ;ariable Vhuman factorV has been reduced.

• Superior Machining

• Sound metal and no hidden sand in the castings means fewer setups# reducedscrap and longer tool life.

• 8ow ooling ,osts

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• )ll patterns are made from epoBy# machined plastics# S8) or 8DM. here



)ll patterns are made from epoBy# machined plastics# S8) or 8DM. here

is no need to retool for production Auantities.

• 7nlimited !attern 8ife• !atterns are protected by plastic film during each sand molding cycle.

• 0asy &e'isions o !atterns

• 5o metal tooling to weld or mill. 6reat for prototypes.

• Short-&un !roduction ,apability

• 0Bcellent for short-run production while waiting for hard tooling. he ;-!&,0SS method can outproduce traditional prototype methods such as

plaster or in'estment castings.

• Fast urnaround

• From placement of order to sample casting in as little as two to four weeks.

ITC

,05&4F76)8 ,)S456



• po!)ts:• +e)se stuctue, clea)e, %oe!*) eleme)ts

se*e*ated /!))e su%ace8

• 1ass poduct!o) w!th less eect!o)

• Ru))es, !ses, coes ao!ded

• Impoed mecha)!cal popet!es

• Close d!me)s!o)s poss!le, less mach!)!)*

• &h!))e sect!o)s poss!le• A)" metal ca) e cast

ITC

- po!)ts:



po!)ts:

- O)l" %o c"l!)d!cal a)d a))ula pats w!th l!m!ted

a)*e o% s!9es

- ;!*h !)!t!al cost

- S.!lled laou )eeded

- &oo h!*h speed leads to su%ace cac.s- /h!*h

stesses !) the mould 8

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CENTRIFUGAL CASTING



• <nown for se'eral hundred years.

• 9ut its e'olution into a sophisticated production method for otherthan simple shapes has taken place only in this century.

• oday# 'ery high Auality castings of considerable compleBity areproduced using this techniAue.

AN OVERVIEW

ITC

• o make a centrifugal casting# molten metal is poured into aspinning mold.



• he mold may be oriented horiontally or 'ertically# depending onthe castingXs aspect ratio.

• Short# sAuare products are cast 'ertically while long tubularshapes are cast horiontally. 4n either case# centrifugal force holdsthe molten metal against the mold wall until it solidifies.

• ,arefully weighed charges ensure that Tust enough metal freeesin the mold to yield the desired wall thickness.

• 4n some cases# dissimilar alloys can be cast seAuentially to producea composite structure.

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• For copper alloy castings# moulds are usually made from carbonsteel coated with a suitable refractory mold wash.



• Molds can be costly if ordered to custom dimensions# but thelarger centrifugal foundries maintain sieable stocks of molds indiameters ranging from a few centimetres to se'eral metres.

• he inherent Auality of centrifugal castings is based on the factthat most nonmetallic impurities in castings are less dense thanthe metal itself. ,entrifugal force causes impurities "dross# oBides$

to concentrate at the castingXs inner surface. his is usuallymachined away# lea'ing only clean metal in the finished product.

• 9ecause freeing is rapid and completely directional# centrifugalcastings are inherently sound and pressure tight.

• Mechanical properties can be somewhat higher than those ofstatically cast products.

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• ,entrifugal castings are made in sies ranging fromapproBimately %/ mm to m in diameter and from a fewinches to many yards in length.

• Sie limitations# if any# are likely as not based on thefoundryXs melt shop capacity.

• Simple-shaped centrifugal castings are used for items suchas pipe flanges and 'al'e components# while compleBshapes can be cast by using cores and shaped molds.

• !ressure-retaining centrifugal castings ha'e been found to

be mechanically eAui'alent to more costly forgings andeBtrusions.

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CENTRIFUGAL CASTING - ANIMATION



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ITC

PRODUCTS9rake drum for commercial highway ,lass + trucks and trailers.



• MaterialE6ray iron.

• !rocessE ,entrifugal casting.• his +-lb brake drum is produced by casting gray

iron centrifugally into a steel shell. his shell acts asa protecti'e Tacket# resulting in superior drumstrength and allowing for the remo'al of iron in thedrum band and mounting areas normally reAuiredin a full cast brake drum.

• hrough concerted efforts between the foundry#machine shop and engineeringCtesting resources# ( lbwere remo'ed from the brake drum while pro'idingthe same performance# balance and reliability as thestandard drum. :ith the weight optimied at + lb#the drums are ideal for weight sensiti'e applicationssuch as refrigerated trailers# tankers and bulkhaulers.

•7tiliing these drums on an 1+-wheel tractorCtrailerapplication can pro'ide up to 22 lb of weightsa'ings.

ITC

9rake drum for commercial highway ,lass + trucks and trailers.

Commercia prod!cts made "#centri$!ga casting



centri$!ga casting

• 6elt uc.les, atte" lu* )uts, loc. pats, pot

metal *eas a)d mach!)e pats, ush!)*s,

medall!o)s, %!*u!)es, soue)!s, memo!al co!)sa)d pla'ues, to" a)d model pats, co)cete

e(pa)s!o) %aste)es, hadwae such as dawe

pulls a)d .)os, ha)dles, decoat!e wall sw!tch

plates etc# etc#

ITC

INTRO%UCTION



INTRO%UCTION • 4n'estment casting# often called lost waB casting# is

regarded as a precision casting process to fabricate near-

net-shaped metal parts from almost any alloy. )lthough its

history lies to a great eBtent in the production of art# the

most common use of in'estment casting in more recent

history has been the production of components reAuiring

compleB# often thin-wall castings. ) complete description of

the process is compleB. 9ut# the seAuential steps of the

in'estment casting process are as below# with emphasis oncasting from rapid prototyping patterns.

ITC

http://wtec.org/loyola/rp/fh10_01.gif



Fig: 1- Investment casting process ITC

• he in'estment casting process begins with fabrication of asacrificial pattern with the same basic geometrical shape as




p g pthe finished cast part

• !atterns are normally made of in'estment casting waB that

is inTected into a metal waB inTection die. Fabricating theinTection die is a costlier process and can reAuire se'eralmonths of lead time.

• nce a waB pattern is produced# it is assembled with otherwaB components to form a metal deli'ery system# calledthe gate and runner system. he entire waB assembly isthen dipped in a ceramic slurry# co'ered with a sand

stucco# and allowed to dry. he dipping and stuccoingprocess is repeated until a shell of Y(-+ mm "1C-3C+ in$ isapplied.

ITC




Fig. 2- Investment casting process - dewaxing ITC

• nce the ceramic has dried# the entire assembly is placed in asteam autocla'e to remo'e most of the waB.

• )ft t l i th i i t f th t k d




• )fter autocla'ing# the remaining amount of waB that soaked

into the ceramic shell is burned out in a furnace. )t this point#all of the residual pattern and gating material is remo'ed# andthe ceramic mold remains.

• he mold is then preheated to a specific temperature and filled

with molten metal# creating the metal casting. nce the castinghas cooled sufficiently# the mold shell is chipped away from thecasting.

• 5eBt# the gates and runners are cut from the casting# and final

post-processing "sandblasting# machining$ is done to finish thecasting.

(Th% CAD s/' m'%/. $h% sh%//. #' $h% "#$$%! "!'u*%' $h% :u*0C#s$ "!*%ss s s*h%m#$*#//y sh,)

ITC




Fig. 3. Investment casting process –Preheating and pouringITC

• he maTor impact rapid prototyping processes ha'e had on in'estment casting istheir ability to make high-Auality patterns "Fig. %$ without the cost and lead timesassociated with fabricating inTection mold dies.

• 4n addition# a pattern can be fabricated directly from a design engineerXs computer-




# p y g g paided design ",)D$ solid model. 5ow it is possible to fabricate a compleB pattern in

a matter of hours and pro'ide a casting in a matter of days. • 4n'estment casting is usually reAuired for fabricating compleB shapes where other

manufacturing processes are too costly and time-consuming.

• )nother ad'antage of rapid prototyping casting is the low cost of producingcastings in small lot sies.

ITC

;acuum ;essel for the power generation industry

MaterialE4nconel (2%! 4 , i

http://wtec.org/loyola/rp/fh10_05.jpg

http://wtec.org/loyola/rp/fh10_04.jpg



• !rocessE 4n'estment ,asting

• he %-lb casting is one-tenth scale of the 'acuum 'esselfor the 5ational ,ompact Stellarator 0Bperiment"5,S>$ being de'eloped by the !rinceton !lasma8aboratory and the ak &idge 5ational 8aboratory asthe neBt generation of fusion eBperiment. he scalemodel was in'estment cast to determine the feasibility ofusing a casting for a 'acuum 'essel with compleBgeometry.

• o meet the rush timeline "with the help ofbuycastings.com$# S8S rapid prototyping techniAueswere employed to make the complicated waB patternsfrom a ,)DCS8 file in 2 weeks. Solidification modelingpredicted the potential Zhot spots[ and ways to optimiethe pour parameters.

• he foundry employed a 'acuum-assist casting methodto cast the 4nconel (2% air melt alloy with a consistentwall thickness of /.1 in. he entire 'essel is assembled bywelding three eAual segments cast by the foundry.

ITC

,am clamp used to secure ambulance gurnees.

MaterialEStainless steel.! 4 t t ti



• !rocessE 4n'estment casting.

• he casting design reAuires intricate anglesand surface profiles\the dimensionalintegrity of the profile angles ha'e to beheld to ]/.//% in.Clinear in. tolerances whileheliB and spiracle angles mo'e bothhoriontally and 'ertically.

• he foundry redesigned the component to

remo'e material from the rear castingsection for weight reduction. 4n addition#the founry designed in a tapered bore formounting a bearing during assembly.

• he casting reAuires slotting at the top andbottom to align mating components. olesat the top and bottom are cast-in and siedas ready-to-tap.

ITC

Mounting bracket for medical centrifuge.

MaterialE,F3M stainless steel.



!rocessE 4n'estment casting.

• his casting pro'ides balanced#'ibration-free support to a centrifugethat turns at more than 1/// &!M.

• riginally designed as a machinedweldment# in'estment castingreduced costs by %/ and pro'idedthis precision component withdimensional repeatability and high-strength Aualities.

• o date# the customer has recei'ed+// parts without encountering

casting-related defects.

ITC

)n ice cutter used in an industrial ice machine.

MaterialE31( stainless steel.




• ,on'erted from a stainless steel fabricationconsisting of stampings# bar stack and aform rolled base# this one-piece casting has anenhanced o'erall efficiency and performance.

• he con'ersion to casting reduced thecustomerXs annual cost by more than

W1//#///# eliminated eBtensi'e straighteningoperations due to warping in the weldingprocess# and reduced the componentXs highscrap.

• he finished cast component is supplied bythe foundry after being completely machinedto print specifications and solution-annealed.

ITC

Duck bill for :hite ,ap# 8.8.,. to seal caps on food Tars.

MaterialE31(8 stainless steel.




• ,asting SupplierE 5orthern !recision,asting ,o.# 8ake 6ene'a# :isconsin.

• riginally constructed as a three-piecestampingCweldment# the 3.-o# 3. B 3.1% B1.-in. new casting design offers lighterweight "2 reduction$# a one-piece

construction# increased strength and asmooth sanitary finish "an importantreAuirement for the food ser'ice industry$.

• he con'ersion to casting from a multi-pieceweldment resulted in a */ cost sa'ings forthe customer.

• o accommodate the thin sections of thecomponent# the foundry designed a uniAue

gating and tooling system that uses wedgegates and gating into the top of thecomponent to ensure against porosity.

ITC

) fan frame hub for 6eneral 0lectricHs ,F-(-+/, engine

for 9oeingHs **# *(* and MD-11 aircraft.

MaterialEitanium.




• his single %2-in. titanium in'estmentcasting replaced ++ stainless steel parts"from fi'e 'endors$ that werepre'iously machined and weldedtogether.

• he casting# which supports the frontfan section of the engine and ties it tothe compressor section# pro'idesimpro'ed strength and dimensionalcontrol in addition to a %% weightreduction.

• ,on'ersion to a metal casting allowed

60 to include se'eral uniAue detailsincluding bosses# flanges and a 2-in.larger o'erall diameter.

ITC

&acing car upright for Minardi Formula 1.

MaterialEitanium (2(.• !rocessE 4n'estment casting




• 5ormally manufactured 'ia machining orwelding# four of these one-piece castcomponents were manufactured 'ia rapidprototyping and in'estment casting fromdesign to deli'ery in + weeks.

• 7sing rapid prototyping with the

in'estment casting process eliminated anup-to-W%/#/// tooling cost for thesecomponents.

• he cast titanium pro'ided the samestrength\but at a reduced weight\as 1*-! steel "the other material considered$.4n addition# with no welds reAuired to

manufacture the components# they donHtreAuire any rework during use.

ITC

ousing actuator for an engine for amiltonSundstrand.

MaterialE)2/3 aluminum alloy.




• :ith wall thickness to /.12 in.# thiscasting reAuires moderate strength#good stability and resistance to stress-corrosion cracking to (//F "31(,$.

• his casting eBhibits mechanicalproperties at room temperature of 32-ksi tensile strength# 2-ksi yieldstrength and 1.% elongation# whilemaintaining a 1(-ksi tensile strengthand elongation at (//F.

• he componentXs as-cast surfacefinish meets the customerXs

reAuirements# and the in'est castingprocess reduced the customerXsfinishing and machining costs.

ITC

Spacer component for an aerospace radar system.

MaterialE1*-! steel#




• ,on'erted from a

weldment# the cast designreduced component weightand machining timereAuired.

• he 1-lb component is castnear-net-shape with erodraft and webbed walls.

ITC

) laser chassis "housing$ for an 4sraeli )ircraft4ndustries night targeting system.

MaterialE)3%* aluminum alloy.



• !rocessE 4n'estment "lost waB$ casting.

• !re'iously machined from )(/(1aluminum wrought alloy# thecomponent was redesigned forin'estment casting at a cost sa'ings of

W2%#///Cpart.• he casting achie'es mechanical

properties of 1 ksi tensile strength# 31ksi yield strength and 3 elongation inareas up to 2.% mm thick and 3+ ksitensile strength# 2+ ksi yield strengthand % elongation in areas o'er 2.%

mm thick.

ITC

,)&95-D4 >4D0 !&,0SS/S484,)0 95D0D S)5D !&,0SS$



/S484,)0 95D0D S)5D !&,0SS$

• F4&S 45 1%/s

• M4>7&0 F S)5D )5D 1.% ( SD47M S484,)0 ")S 945D0&$

• M4>7&0 !),<0D )&75D 0!)0&5# )&D050D 9 98:456 ,2

• D0;08!0D F7&0& 9 )DDD4560& ,0M4,)8S )S 945D0&S

• M)458 M)<0 ,&0S-)S 7S0 4S 45

080;)0D 0M!0&)7&0 )!!84,)45

ITC

5a2 Si2 O 2 O,2 5a2,3 O "Si2 O2$ "Silica 6el$

Formation of Silica 6el gi'es strength to the moulds



Formation of Silica 6el gi'es strength to the moulds

O !ointsE

• Drying not necessary

• 4mmediately ready for pouring

• ;ery high strength achie'ed

• Dimensional accuracy 'ery good- !oints

- ,ollapsibility poor# can be impro'ed by additi'es

- 5a2 Si2 attacks and spoils wooden pattern

ITC



,2

Funnel

,2 Moulding

Mould

ITC

D0S465 ,5S4D0&)45S



,)&0F78 ,5&8 F 8)&60 57M90& F;)&4)980S 500D0D-

• ,)&),0&4S4,S F M0)8S ? )88S,)S

• M0D F ,)S456

• M78D )5D D40 M)0&4)8S• M78D D0S465

• !&,0SS !)&)M00&S- !7&456#0M!0&)7&0#

• 6)456 SS0M• &)0 F ,8456 0tc.0tc.

ITC

• $oo cast!)* pact!ces, lac. o% co)tol o% pocess



$oo cast!)* pact!ces, lac. o% co)tol o% pocess

a!ales- +E=EC&IVE CAS&INGS

• &O AVOI+ +E=EC&S-

• 6as!c eco)om!c %actos elea)t to cast!)*opeat!o)s to e stud!ed#

• Ge)eal *u!del!)es appl!ed %o all t"pes o% cast!)*s

to e stud!ed#

ITC

,&50&S# )5680S )5D S0,45 4,<50SS

• Sharp corners# angles# fillets to be a'oided



Sharp corners# angles# fillets to be a'oided

,ause cracking and tearing during solidification• Fillet radii selection to ensure proper liAuid metal flow-

3mm to 2% mm.

oo large- 'olume large ? rate of cooling less

• 8ocation with largest circle inscribed critical.

,ooling rate less

shrinkage ca'ities ? porosities result-

,alled S!S

ITC

• LARGE =LA& AREAS &O 6E AVOI+E+-:)&!456 D70 0M!0&)7&0 6&)D405S

• )88:)5,0S F& S&45<)60 90 !&;4D0D



• )88:)5,0S F& S&45<)60 90 !&;4D0D

• !)&456 8450 90 )856 ) F8) !8)50-

6D ) ,&50&S & 0D60S F ,)S456

• D&)F 90 !&;4D0D

•!0&M4SS4980 80&)5,0S 90 7S0D

• M),45456 )88:)5,0S 90 M)D0

• &0S4D7)8 S&0SS0S 90 );4D0D

ALL THESE FOR EXPENDA4LE MOULD CASTINGS 2

ITC

• D0S465 MD4F4,)45S );4D D0F0,S-

• );4D S)&! ,&50&S



• M)45)45 754F&M ,&SS S0,45S• );4D S&45<)60 ,);440S

• 7S0 ,488S 45,&0)S0 0 &)0 F ,8456

• S)660& 450&S0,456 &0645S F&

754F&M ,&SS S0,45S

• &0D0S465 9 M)<456 !)&456 8450 S&)46

• );4D 0 7S0 F ,&0S# 4F !SS4980

• M)45)45 S0,45 4,<50SS 754F&M4

9 &0D0S465456 "in die cast products$

ITC

!&!0&40S )5D !4,)8 )!!84,)45S F



!&!0&40S )5D !4,)8 )!!84,)45S F

,)S 4&5S# 55 F0&&7S )88S etc.

&ales shall e suppl!ed

ITC

6eneral ,ost ,haracteristics of

,asting !rocesses



,asting !rocesses!&,0SS ,S !&D7,45

&)0 "pcChr$D40 0I74!M05 8)97&

S)5D 8 8 8-M ^2/

S088 8-M M- 8-M ^%/

!8)S0& 8-M M M- ^1/

45;0SM05 M- 8-M ^1///

!0&M)505M78D M M 8-M ^(/

D40 8-M ^2//

,05&4F76)8 M 8-M ^%/ ITC



THIXOTROPIC DIE

CASTI G

Some of the die-cast Toints used in the 4nsightXs aluminum

body are made using a newly de'eloped casting technologyin'ented by onda engineers# called hiBotropic Die

,asting.

hiBotropic Die ,asting uses aluminum alloy that has been ITC

owe'er# hiBotropic Die ,asting reAuires less energy for



# p g A gy

smelting "an important consideration since aluminum is moreeBpensi'e than steel$# and owes much of its strength to the

controlled formation of discrete aluminum crystals within the

metal casting.

hiBotropic casting in'ol'es 'ibratory casting of highly

thiBotropic slips of 'ery high solids loadings that are fluid only

under 'ibration# using porous or nonporous molds.

4t is Auite different from other con'entional and new methodsfor solid casting ceramics# including 'ibroforming#

'ibraforming# s$u flocculation# direct coagulation casting#

and gel casting. ITC

,asting Method and MaTor Features Differentiating !roperties of hiBotropic

,asting

,ement is not reAuired for setting

able 1. hiBotropic casting in comparison with the alternati'es.



;ibroforming Q &eAuires a cement forsetting

,ement is not reAuired for setting

;ibraforming Q &eAuires eBcess counter

ions and centrifugation for settling )ddition of organic deflocculantCbinder

and 'ibration are the only necessary

steps

4n situ flocculation Q reAuires theaddition of urea and heating to control

the p to the isoelectric point

5o urea additions# heating# control ofp# or attainment of the isoelectric point

are reAuired

4nTection moulding Q reAuired large

Auantities "1%-3/wt$ of entraining

polymer and pressuried mould feeding

nly traces "^1$ of binder are needed

and no pressure needed for filling of

moulds

Direct coagulation casting Q reAuires

control of the p through an enyme

catalysed decomposition reaction

5o enyme additions or control of p

are reAuired

6el casting Q reAuires use of a

neurotoBin to cause polymeric gelling

5o polymer additi'e or polymeriation

are reAuired ITC

hiBotropic casting is a little-known deri'ati'e of solid slip

casting# ha'ing reportedly been used in the refractories industry

in the early 1*/Xs.



Since then# the refractories industry has since largely embracedlow-cement and ultra-low-cement castables.

4t is also a suitable process for forming ceramic matriB

composites and metal-ceramic functionally gradient materials.

hiBotropic casting in'ol'es 'ibratory casting of highly

thiBotropic slips of 'ery high solids loadings that are fluid only

under 'ibration# using porous or nonporous molds.

4t is Auite different from other con'entional and new methods

for solid casting ceramics# including 'ibroforming#

'ibraforming# s$u flocculation# direct coagulation casting#and gel casting.

(Ths s '%ms$!#$%' T#/% 5)

ITC



ITC



ITC

0Tector !ump

he eTector pump is a type



of 'acuum pump. 6as isremo'ed from a container

by passing steam or water at

a high 'elocity through a

chamber that is connected

to the container. he miBing

chamber contains both the

gas from the container and

the steam or water. )t the

inlet port# the eTector pumpis connected to the

container that is being

e'acuated. ITC

• 1elt!)*



ITC

!8)S0& M78D ,)S456• For casting sil'er# gold# )l# Mg# ,u# and alloys of brass and

brone.

• !laster of !aris "6ypsum$ ",aSo.n2$ used for cope and drag



!laster of !aris "6ypsum$ ",aSo.n2$ used for cope and drag

moulding• ) Slurry of 1// parts metal casting plaster and 1(/ parts water

used.

• !laster added to water and $ ,#$%! $ "/#s$%! . T "!%1%$ *!#*0s.

;6-<67 $#/* #''%' $ "/#s$%!2 Lm% #' *%m%$ $ *$!/ %="#s• Stirred slowly to form cream !oured carefully o'er a match plate

pattern "of metal$

• Mould 'ibrated to allow plaster to fill all ca'ities.

• 4nitial setting at room temperature"setting time reduced by eitherheating or by use of terra-albaC magnesium oBide$

• !attern remo'ed

• ,ope and drag dried in o'ens at 2//- 2% ,"about 2/ hours$

• Mould sections assembledITC

O points

• +!me)s!o)al accuac" #F t #0 mm pe mm



• E(celle)t su%ace %!)!sh as )o sa)d used## No %uthemach!)!)* o *!)d!)*

• No) %eous th!) sect!o)ed !)t!cate cast!)*s made#

- points• L!m!ted to )o) %eous cast!)*s#/sulphu !) *"psum

eacts w!th %eous metals at h!*h tempeatues8

• Ve" low pemea!l!t" as metal moulds used# 1oulds

)ot pema)e)t, desto"ed whe) cast!)*s emoed#

ITC

F&=05 M0&,7& M78D456"M0&,)S !&,0SS$

• Froen Mercury used for producing precision castings



• Metal mould prepared to the shape with gates and sprue holes• !laced in cold bath and filled with acetone "to act as lubricant$

• Mercury poured into it# freees at Q2/ ,# after a few minutes"1/mins$

• Mercury !attern remo'ed and dipped in cold ceramic slurrybath.

• ) shell of 3 mm is built up. Mercury is melted and remo'ed atroom temperature.

• Shell dried and heated at high temperature to form hard

permeable shape.• Shell placed in flask- surrounded by sand-# preheated and

filled with metal.

• Solidified castings remo'ed. ITC

• =o oth %eous a)d )o) %eous cast!)*s#/melt!)*

tempeatue upto 0P5/C8



• Ve" accuate deta!ls ota!)ed !) !)t!cate shapes

• E(celle)t su%ace %!)!sh, mach!)!)* a)d clea)!)*

costs m!)!mum#

• Accuac" o% #2 mm pe mm ota!)ed#

• 4u$. *#s$+ "!*%ss *s$/y2

• C#s$+ *s$ h+h2

ITC

45S!0,45 F ,)S456S



• S0;0&)8 M0DS• ;4S7)8

• !4,)8

•- F& S7&F),0 D0F0,S• S79S7&F),0 )5D 450&5)8 D0F0,S&76 5Ds ? Ds

• !&0SS7&0 4650SS F ;)8;0S 9

S0)8456 0 !05456 )5D!&0SS7&4S456 :4 :)0&

ITC

CAS&ING +E=EC&S



S7&F),0

M0)884, !&P0,45 "$

D0F0,4;0 S7&F),0 "11$

,)560 45 D4M05S45- :)&!45,M!800 ,)S456

M4S&75# &757

,);4-

98:80S# S&45<)60

!4580S

D4S,54574

,&),<

,8D S7# ,8D ,&),<

SU6SUR=ACE

SU6SUR=ACE CAVI&

INCLUSIONS

+ISCON&INUI&

ITC

N+&s



1ethods o% test!)*

+estuct!e-

No) destuct!e-

Rad!a*aph!c

Ultaso)!c

ITC



No) +estuct!e &est!)*

w!th Ultaso)!cs

%o %law +etect!o) !) Cast!)*s,7eldme)ts, Ra!ls, =o*ed Compo)e)ts etc#

ITC



78&)S54, 0S456

ITC

7h" Ultaso)!cs Q



=law detect!o) !) metals a)d )o)metals

=law measueme)t !) e" th!c. mate!alsI)te)al a)d su%ace %laws ca) e detected

I)spect!o) costs ae elat!el" low#

Rap!d test!)* capa!l!t!es a)d pota!l!t"#

ITC

Utrasonic &a'es are simp#'i"rationa &a'es ha'ing a $re(!enc#



higher than the hearing range o$ thenorma h!man ear) &hich is t#pica#considered to "e *+)+++ c#ces persecond ,-./0The !pper end o$ the range is not &e

de1ned0 Fre(!encies higher than 2+G-. ha'e "een generated0 -o&e'er)most practica !trasonic 3a&detection is accompished &ith

$re(!encies $rom *++ 4-. to *+ 5-.)&ith 6+ 5-. !sed in materia propert#in'estigations0 Utrasonic energ# can"e !sed in materias and str!ct!res$or 3a& detection and materia

ITC

• Ultaso)!c waes ae mecha)!cal waes/!) co)tast to, %o e(ample, l!*ht o (-



a"s, wh!ch ae electoma*)et!c waes8that co)s!st o% osc!llat!o)s o !at!o)so% the atom!c o molecula pat!cles o% asusta)ce aout the e'u!l!!um

pos!t!o)s o% these pat!cles# Ultaso)!cwaes ehae esse)t!all" the same asaud!le sou)d waes# &he" ca)

popa*ate !) a) elast!c med!um, wh!ch

ca) e sol!d, l!'u!d, o *aseous, ut )ot!) a acuum#

ITC

4n solids# the particles can "a$ oscillate along the direction of soundpropagation as longitudinal wa'es# or "b$ the oscillations can be

perpendicular to the direction of sound wa'es as trans'erse wa'es.

)t surfaces and interfaces# 'arious types of elliptical or compleB

'ibrations of the particles occur.



ITC

&;EOR O= &ES&ING



ITC

1AC;INE S$ECI=ICA&IONS



1a.e:

7e!*ht:

Cal!at!o) a)*e upto mm#Cho!ce o% =e'ue)c" a)*e

$o!s!o) %o adust!)* *a!)#

+ocume)tat!o) poss!!l!t" !a p!)te L!m!tat!o):#

ITC

$oe



ITC

SCANNING &EC;NI?UES



?

• $ulse Echo method

• Sta!*ht eam method

• A)*le eam method

ITC

$ULSE EC;O 1E&;O+



ITC

I)spect!o) o%:



• Gas poos!t"

• Sla* E)tapme)t

• Cac.s

ITC



With the exception of singe g!s po"es !the #efects iste# !"e $s$!% &e#etect!'e '% $t"!sonics(

Ut"!sonic *!& #etection h!s ong 'eenthe p"efe""e# +etho# fo" non#est"$cti,etesting +!in% in &e#ing !ppic!tions(

This s!fe !cc$"!te !n# si+pe techni.$eh!s p$she# $t"!sonics to the fo"ef"ont ofinspection technoog%(

ITC

The p"ope" sc!nning !"e! fo" the &e#/



Fi"st c!c$!te the oc!tion of the so$n#'e!+ in the test +!te"i!(

Using the refracted angle, beam index point and material thickness, the V-path

and skip distance of the sound beam isfound 0

Then i#entif% the t"!ns#$ce" oc!tionson the s$"f!ce of the +!te"i!co""espon#ing to the c"o&n si#e&!!n# "oot of the &e#(

ITC



ITC



ITC

I)spect!o) o% Ra!ls



ITC



ITC

•



5ew trendE7ltrasonic Simulation - 7S4M

U&SI1 !s a use !)te%ace !)te*at!)* a

CA+ model epese)t!)* a pat u)de!)spect!o) a)d a) ultasou)d eam

model#

ITC



ITC



ITC

Ul!"#$*i #i3i* $( #%"ll (l")# )i!h

!he i#!"*e-"%2li!ue-$e!i$* /"1 u+e

introduction to casting defects

Documents