10/9/2011

1

Special CastingSpecial Casting

By  S K Mondal

Shell MouldingThe sand is mixed with a thermosetting resin isallowed to come in contact with a heated metal pattern(2000C).A ki ( h ll) f b f d d l iA skin (shell) of about 3.5 mm of sand and plasticmixture adhere to the pattern.Then the shell is removed from the pattern.The cope and drag shells are kept in a flask withnecessary backup material and the molten metal ispoured into the mold.

Can produce complex parts.

A good surface finish and good size tolerance

reduce the need for machining.g

Materials can be cast: CI, Al and Cu alloys.

Shell moulding process

Molding Sand in Shell MoldingThe molding sand is a mixture of fine grained quartz sand

and powdered bakelite.

Cold coating and Hot coating methods are used forCold coating and Hot coating methods are used for

coating the sand grains with bakelite.

Cold coating: quartz sand is poured into the mixer and

then the solution of powdered bakelite in acetone and

ethyl aldehyde are added. (mixture is 92% quartz sand,

5% bakelite, 3% ethylaldehyde )Contd…

Hot coating: the mixture is heated to 150oC– 180oC prior

to loading the sand. In the course of sand mixing, the

soluble phenol formaldehyde resin is added. The mixer is

allowed to cool up to 80 – 90o C. Hot coting gives better

properties to the mixtures than cold method.

10/9/2011

2

AdvantagesDimensional accuracy.

Smoother surface finish. (Due to finer size grain used)

Very thin sections can be cast.y

Very small amount of sand is needed.

LimitationsExpensive pattern

Small size casting only.

Highly complicated shapes cannot be obtained.

More sophisticated equipment is needed for handling

the shell moldings.

ApplicationsCylinders and cylinder heads for air‐ cooled IC

engines

Automobile transmission parts.

Piston rings

IES 2010Consider the following advantages of shell mould casting:

1. Close dimensional tolerance.2. Good surface finish.3. Low cost.4. Easier.Which of these are correct?(a) 1, 2 and 3 only  (b) 2, 3 and 4 only(c) 1, 2 and 4 only  (d) 1, 2, 3 and 4

IES‐1996Consider the following ingredients used inmoulding:

1. Dry silica sand2.Clay2.Clay3.Phenol formaldehyde4.Sodium silicateThose used for shell mould casting include(a) 1, 2 and 4 (b) 2, 3 and 4(c) 1and 3 (d) 1, 2, 3 and 4

IES‐2005In shell moulding, how can the shell thickness be accurately maintained?

(a) By controlling the time during which the pattern is in contact with mould      

(b) By controlling the time during which the pattern is heated

(c) By maintaining the temperature of the pattern in the range of 175oC – 380oC

(d) By the type of binder used

10/9/2011

3

IES‐2006Shell moulding can be used for:(a) Producing milling cutters(b) Making gold ornaments(c) Producing heavy and thick walled casting(c) Producing heavy and thick walled casting(d) Producing thin casting

IES 2007

Which of the following are employed in shellmoulding?1. Resin binder 2. Metal pattern 3. Heating coilsSelect the correct answer using the code givenbelow:(a) 1 and 2 only (b) 1 and 3 only(c) 2 and 3 only (d) 1, 2 and 3

IAS‐2007The mould in shell moulding process is made up

of which of the following?

(a) Gypsum + setting agents(a) Gypsum + setting agents

(b) Green sand + clay

(c) Sodium silicate + dried sand

(d) Dried silica + phenolic resin

IAS‐1999Match List I (Moulding Process) with List II (BindingAgent) and select the correct answer using the codesgiven below the lists:

List I List IIA. Green sand 1. SilicateB. Core sand 2. OrganicC. Shell moulding 3. ClayD. CO2 process 4. Plaster of Paris

5. PlasticCodes:A B C D A B C D(a) 3 2 5 1 (b) 3 2 4 1(c) 2 3 5 4 (d) 2 3 4 5

Investment CastingInvestment casting process or lost wax processBasic steps:1. Produce expendable wax, plastic, or polystyrene patterns.2. Assemble these patterns onto a gating system3 Investing or covering the pattern assembly with refractory3. Investing or covering the pattern assembly with refractoryslurry

4.Melting the pattern assembly to remove the pattern material5. Firing the mould to remove the last traces of the patternmaterial

6.Pouring molten metal7. Knockout, cutoff and finishing.

Fig. Investment flask‐casting procedure

10/9/2011

4

Ceramic Shell Investment CastingIn ceramic shell investment casting a ceramic shell is

built around a tree assembly by repeatedly dipping a

pattern into a slurry (refractory material such aspattern into a slurry (refractory material such as

zircon with binder).

After each dipping and stuccoing is completed, the

assembly is allowed to thoroughly dry before the next

coating is applied.

IES 20092 marks

AdvantagesTight dimensional tolerances

Excellent surface finish (1.2 to 3.0 μm )

Machining can be reduced or completelyg p y

eliminated

High melting point alloy can be cast, almost any

metal can be cast

Almost unlimited intricacy

Limitations

Costly patterns and moulds

Labour costs can be high

Limited size

10/9/2011

5

Applications

Aerospace and rocket components.

Vanes and blades for gas turbines.

Surgical instruments

IES 2011The proper sequence of investment casting steps is :(a) Slurry coating – pattern melt out‐Shakeout – Stuccocoating(b) Stucco coating – Slurry coating – Shakeout – Patternmelt out(c) Slurry coating – Stucco coating – Pattern melt out –Shakeout(d) Stucco coating – Shakeout – Slurry coating – Patternmelt out

GATE‐2006

An expendable pattern is used in(a) Slush casting(b) Squeeze casting(c) Centrifugal casting(d) Investment casting

IES‐1992The most preferred process for casting gas turbine blades is:(a) Die moulding(b) Shell moulding(b) Shell moulding(c) Investment moulding(d) Sand casting

JWM 2010Consider the following materials :1. Wax 2. Wood3. PlasticWhich of these materials can be used as pattern in investment casting process ?(a) 1, 2 and 3  (b) 1 and 2 only(c) 2 and 3 only  (d) 1 and 3 only

IES 2010Assertion (A): These investment casting is used forprecision parts such as turbine plates, sewingmachines etc.Reason (R): The investment castings have a goodsurface finish and are exact reproductions of thesurface finish and are exact reproductions of themaster pattern.(a) Both A and R are individually true and R is thecorrect explanation of A(b) Both A and R are individually true but R is NOT thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

10/9/2011

6

IES 2007Consider the following statements in respect ofinvestment castings:1. The pattern or patterns is/are not joined to a stalk orsprue also of wax to form a tree of patterns.2.The prepared moulds are placed in an oven and heatedgently to dry off the invest and melt out the bulk of wax.3.The moulds are usually poured by placing the moulds ina vacuum chamber. Which of the statements given aboveare correct?(a) 1 and 2 only (b) 1 and 3 only(c)2 and 3 only (d) 1, 2 and 3

IES‐2006Which of the following materials are used formaking patterns in investment casting method?1. Wax 2. Rubber 3. Wood 4. PlasticSelect the correct answer using the codes given below:Select the correct answer using the codes given below:(a) Only 1 and 3 (b) Only 2 and 3(c) Only 1, 2 and 4 (d) Only 2, 3 and 4

IAS‐1996Light and intricate parts with close dimensionaltolerances of the order of ± 0.005 mm areproduced by(a) Investment castingg(b) Die casting(c) Centrifugal casting(d) Shell mould casting

Permanent Mould CastingThe process in which we use a die to make thecastings is called permanent mold casting or gravitydie casting, since the metal enters the mold undergravitygravity.Some time in die‐casting we inject the molten metalwith a high pressure. When we apply pressure ininjecting the metal it is called pressure die castingprocess.Grey cast iron is used for mould material.

AdvantagesGood surface finish and dimensional accuracyMetal mold gives rapid cooling and fine‐grainstructureMultiple‐use molds.

DisadvantagesHigh initial mold costShape, size, and complexity are limitedMold life is very limited with high‐melting‐pointmetals such an steelmetals such an steel.Low melting point metals can be cast‐ Aluminum‐ Zinc‐ Magnesium alloys‐ Brass‐ Cast iron

10/9/2011

7

Applications

Pistons/cylinders/rods

Gears

Kitchenware

Die CastingMolten metal is injected into closed metal dies under

pressures ranging from 100 to 150 MPa.

Pressure is maintained during solidificationPressure is maintained during solidification

After which the dies separate and the casting is ejected

along with its attached sprues and runners.

Cores must be simple and retractable and take the

form of moving metal segments

Video

Die casting machines can be

Hot chamber

Cold chamber

Hot chamber machines areGood for low temperature (approx. 400°C)Faster than cold chamber machinesCycle times must be short to minimize metalcontaminationMetal starts in a heated cylinderA piston forces metal into the dieThe piston retracts, and draws metal inMetal: Lead, Tin, Zinc

Hot Chamber

10/9/2011

8

Cold chamber machines

Casts high melting point metals ( > 600°C)

High pressures used

l h d blMetal is heated in a separate crucible

Metal is ladled into a cold chamber

The metal is rapidly forced into the mold before it 

cools

Copper, Brass and Aluminium can cast.

AdvantagesExtremely smooth surfaces  (1 µm)

Excellent dimensional accuracy

Rapid production rate

Better mechanical properties compared to sand 

casting

Intricate parts possible

Minimum finishing operations

Thin sections possible

LimitationsHigh initial die cost

Limited to high‐fluidity nonferrous metals

Part size is limited

Porosity may be a problem

Some scrap in sprues, runners, and flash, but this can 

be directly recycled

ApplicationsCarburettorsAutomotive partsBathroom fixturesToys

CommonmetalsAlloys of aluminum, zinc, magnesium, and leadAlso possible with alloys of copper and tin

10/9/2011

9

IES 2011Consider the following advantages of die casting oversand casting :1. Rapidity of the process2. Smooth surface3 Strong dense metal structure3. Strong dense metal structureWhich of these advantages are correct ?(a) 1, 2 and 3(b) 1 and 2 only(c) 2 and 3 only(d) 1 and 3 only

IES‐2009Which of the following are the most suitablematerials for die casting?(a) Zinc and its alloys(b) Copper and its alloys(b) Copper and its alloys(c) Aluminium and its alloys(d) Lead and its alloys

JWM 2010Assertion (A) : In die casting method, smallthickness can be filled with liquid metal.Reason (R) : The air in die cavity trapped inside thecasting causes problems.(a) Both A and R are individually true and R is the (a) Both A and R are individually true and R is the correct explanation of A(b) Both A and R are individually true but R is not the correct explanation of A (c) A is true but R is false(d) A is false but R is true

IES‐2005Which one of the following processes produces acasting when pressure forces the molten metalinto themould cavity?(a) Shell moulding (b) Investment castingg g(c) Die casting (d) Continuous casting

IES‐2006In which of the following aremetal moulds used?(a) Greensand mould(b) Dry sand mould(c) Die casting process(c) Die casting process(d) Loammoulding

IES‐1995Assertion (A): An aluminium alloy with 11 % silicon isused for making engine pistons by die castingtechnique.Reason (R): Aluminium has low density and additionof silicon improves its fluidity and therefore itsp ycastability.(a) Both A and R are individually true and R is the correctexplanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

10/9/2011

10

IES‐1995Match List I with List II and select the correct answer taking the help of codes given below the lists:List I List II (Products) (Process of manufacture)A. Automobile piston in aluminium alloy 1. Pressure die‐castingB. Engine crankshaft in spheroidal

hi  i  G i  di igraphite iron 2. Gravity die‐castingC. Carburettor housing in aluminium alloy 3. Sand castingD. Cast titanium blades 4. Precision investment 

casting5. Shell moulding

Code: A B C D A B C D(a) 2 3 1 5 (b) 3 2 1 5(c) 2 1 3 4 (d) 4 1 2 3

IAS‐2007Consider the following statements:1. Zinc die castings have low strength.2. In the die casting process, very thin sections or complex shapes can be obtained easily.complex shapes can be obtained easily.Which of the statements given above is/are correct?(a) 1 only(b) 2 only(c) Both 1 and 2(d) Neither 1 nor 2

IAS‐1996Assertion (A): Die casting yields a product of goodaccuracy and finish.Reason (R): Low melting alloys used in diecasting.( ) B h A d R i di id ll d R i h(a) Both A and R are individually true and R is thecorrect explanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

IES 2011Consider the following statements :1. Hot chamber machine is used for casting zinc, tin andother low melting alloys.2. Cold chamber machine is used for die casting offerrous alloys3. Rapid cooling rate in die casting produces highstrength and quality in many alloys.Which of these statements are correct?(a) 1, 2 and 3 (b) 1 and 2 only(c) 2 and 3 only (d) 1 and 3 only

GATE‐2007Which of the following engineering materials isthe most suitable candidate for hot chamber diecasting?

( ) b l(a) Low carbon steel(b) Titanium(c) Copper(d) Tin

IES‐1995Assertion (A): Aluminium alloys are cast in hotchamberdie casting machine.Reason (R): Aluminium alloys require high meltingwhen compared to zinc alloys.(a) Both A and R are individually true and R is the correct(a) Both A and R are individually true and R is the correctexplanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false

(d) A is false but R is true

10/9/2011

11

Centrifugal CastingProcess: Molten metal is introduced into a rotating sand,

metal, or graphite mould, and held against the mould

wall by centrifugal force until it is solidified

A mold is set up and rotated along a vertical (rpm isA mold is set up and rotated along a vertical (rpm is

reasonable), or horizontal (200‐1000 rpm is reasonable)

axis.

The mold is coated with a refractory coating.

During cooling lower density impurities will tend to rise

towards the center of rotation.Fig. True centrifugal casting

PropertiesThe mechanical properties of centrifugally cast jobs arebetter compared to other processes, because the inclusionssuch as slag and oxides get segregated towards the centreand can be easily removed by machining. Also, thepressure acting on the metal throughout the solidificationp g gcauses the porosity to be eliminated giving rise to densemetal.No cores are required for making concentric holes in thecase of true centrifugal casting.

AdvantagesFine grained structure at the outer surface of thecasting free of gas and shrinkage cavities andporosityFormation of hollow interiors in cylinders withoutcoresCan produce a wide range of cylindrical parts,including ones of large size.Good dimensional accuracy, soundness, andcleanlinessThere is no need for gates and runners, whichincreases the casting yield, reaching almost 100 %.

LimitationsMore segregation of alloy component during pouring under

the forces of rotation

Contamination of internal surface of castings with non‐

lli i l imetallic inclusions

Inaccurate internal diameter

Shape is limited.

Spinning equipment can be expensive

Poor machinability

10/9/2011

12

Common metalsIronsteelstainless steelalloys of aluminium, copper, and nickel

GATE‐2002In centrifugal casting, the impurities are

(a) Uniformly distributed(b) Forced towards the outer surface(c) Trapped near the mean radius of the casting(d) Collected at the centre of the casting

GATE‐1993Centrifugally cast products have(a) Large grain structure with high porosity(b) Fine grain structure with high density(c) Fine grain structure with low density(c) Fine grain structure with low density(d) Segregation of slug towards the outer skin of thecasting

IES‐2008Which of the following casting processes does not/do not require central core for producing pipe?1. Sand casting process2. Die casting process3 Centrifugal casting process3. Centrifugal casting processSelect the correct answer using the code given below:(a) 1 and 2(b) 2 only(c) 2 and 3(d) 3 only

IES‐2009Which one of the following casting processes is

best suited to make bigger size hollow

symmetrical pipes?y p p

(a) Die casting

(b) Investment casting

(c) Shell moulding

(d) Centrifugal casting

IES 2007Which one of the following is the correctstatement?In a centrifugal casting method(a) No core is used(a) No core is used(b) Core may be made of any metal(c) Core is made of sand(d) Core is made of ferrous metal

10/9/2011

13

IES‐1998Poor machinability of centrifugally cast iron pipe is due to(a) Chilling(b) Segregation(b) Segregation(c) Dense structure(d) High mould rotation speed

IES‐2009Which of the following are the most likelycharacteristics in centrifugal casting?(a) Fine grain size and high porosity(b) Coarse grain size and high porosity(b) Coarse grain size and high porosity(c) Fine grain size and high density(d) Coarse grain size and high density

IES 2007Match List I with List II and select the correct answer using the code given below the Lists:List I List II(Casting Process) (Principle)A. Die casting 1.The metal solidifies in a rotating mouldB. Investment casting 2.The pattern cluster is repeatedly dipped 

into a ceramic slurry and dusted with frefractory

C. Shell moulding 3. Molten metal is forced by pressure into a metallic mould

D. Centrifugal casting 4. After cooling, the invest is removed from the Casting by pressure jetting or vibratory cleaning

Code:A B C D A B C D(a) 2 1 3 4 (b) 3 4 2 1(c) 2 4 3 1 (c)  3 1 2 4

IES‐2000Match List I (Process) with List II (Products/materials) and select the correct answer using the codes given below the Lists:List I  List IIA. Die casting  1. Phenol formaldehydeB. Shell molding  2. C.I. pipesC. CO2 molding  3. Non‐ferrous alloysD. Centrifugal casting  4. Sodium silicate

Codes:A B  C  D  A  B  C  D(a)  1  3  4  2  (b)  3  1  4  2(c)  3  1  2  4  (d)  1  3  2  4

IAS‐2004Match List‐I (Name of the Process) with List‐II (Advantage) and select the correct answer using the codes given below the lists:List‐I List‐II(Name of the Process) (Advantage)A. Sand Casting 1. Large cylindrical parts with good qualityB C i   ld  i E ll  di i l    d  fB. Ceramic mold casting 2.Excellent dimensional accuracy and surface

finishC. Die casting 3. Intricate shapes and close tolerance partsD. Centrifugal casting 4. Almost any metal is cast and there if no limit to

size, shape and weight5. Good dimensional accuracy, finish and lowporosity

Codes:A  B  C  D A  B  C  D(a)  2  3  5  1 (b) 4  1 2 3

(c)  2  1  5  3  (d) 4 3 2 1

Semi‐centrifugal CastingCentrifugal force assists the flow of metal from a

central reservoir to the extremities of a rotating

symmetrical mold, which may be either expendable ory , y p

multiple‐use

Rotational speeds are lower than for true centrifugal

casting

Cores can be used to increase the complexity of the

product.

10/9/2011

14

Fig. Semi‐centrifugal casting

IAS‐2003Assertion (A): Semi‐centrifugal casting process issimilar to true centrifugal casting except that thecentral core is used in it to form inner surface.Reason (R): In semi‐centrifugal casting process theaxis of spin is always verticalp y(a) Both A and R are individually true and R is the correctexplanation of A(b) Both A and R are individually true but R is not thecorrect explanation of A(c) A is true but R is false(d) A is false but R is true

CentrifugingUses centrifuging action to force the metal from a central

pouring reservoir into separate mold cavities that are

offset from the axis of rotation.

Low speed

May used to assist in the pouring of investment casting

trees.

Fig. Method of casting by the centrifuging process

IES‐2000Match List I (Type of casting) with List II (Working principles) and select the correct answer using the codes given below the Lists:List I List IIA. Die casting 1. Molten metal is forced into the die 

under pressureB. Centrifugal casting 2. Axis of rotation does not coincide with 

axis of mouldC.  Centrifuging 3. Metal solidifies when mould is rotatingD. Continuous casting 4. Continuously pouring molten metal 

into mouldCodes:A B C  D A B  C D

(a)  1  3  2  4  (b)  4  3  2  1(c)  1  2  3  4  (d)  4  2  3  1

Dry Sand MoldingTo reduce gas forming materials air dried mould used.

Types:

1 Skin drying and1.Skin drying and

2.Complete mold drying

10/9/2011

15

Slush CastingSlush casting is a variation of the permanent mold processin which the metal is permitted to remain in the mold onlyuntil a shell of the desired thickness has formed.The mold is then inverted and the remaining liquid ispoured out.When the mold halves are separated, the resulting castingis a hollow shape with good surface detail but variable wallthickness.Frequently used to cast low‐melting‐temperature metalsinto ornamental objects such as candlesticks, lamp bases,and statuary.

IAS‐2004Which of the following are produced by slushcasting?(a) Hollow castings with thick walls(b) Hollow castings with thin walls(b) Hollow castings with thin walls(c) Thin castings(d) Thick castings

IES 2011The method of casting for producing ornamental piecesare:(a) Slush and gravity casting(b) Pressed and slush casting(c) Gravity and semi permanent mould casting(d) Semi permanent mould and pressed casting

Squeeze CastingProcess:1. Molten metal is poured into an open face die.2. A punch is advanced into the die, and to the metal.3 Pressure (less than forging) is applied to the punch3.Pressure (less than forging) is applied to the punchand die while the part solidifies.

4.The punch is retracted, and the part is knocked outwith an ejector pin.Overcomes problems with feeding the die, andproduces near net, highly detailed parts.

IAS‐2002Match List I (Casting Process) with List II (Applications) and select the correct answer using the codes given below the Lists:List I  List II(Casting Process)  (Applications)A. Centrifugal casting 1. CarburetorB. Squeeze casting 2. PipesC. Die Casting 3. Wheels for 

automobiles4. Gear housings

Codes:  A B C A B C(a)  2 3 1 (b)  4 1 3(c)  2 1 3 (d)  4 3 1

Single Crystal CastingThe process is effectively:1. Prepare a mold so that one end is a heated oven, and 

the other end chilled. The part should be oriented so that the cooling happens over the longest distance.C t  t l i t  th   ld2. Cast metal into the mold

3. Solidification will begin at the chill plate. These dendrites will grow towards the heated end of the part as long dendritic crystals. The part is slowly pulled out of the oven, past the chill plate.

4. Remove the solidified part.

10/9/2011

16

Creep and thermal shock resistance properties.

IES 2009

2 marks

Plaster CastingProcess: A slurry of plaster, water, and various additives isadditives is pouted over a pattern and allowed to set. Thepattern is removed and the mould is baked to removeexcess water. After pouring and solidification, the mould isbroken and the casting is removed.gAdvantage: High dimensional accuracy and smoothsurface finish, thin sections and intricate detail canproduce.Limitations: Lower‐temperature nonferrous metals only:Commonmetals: Primarily aluminium and copper

Pit MouldingThis method is used for very large castings and is done onthe foundry floor.

IES‐1996Which of the following pairs are correctly matched?1. Pit moulding ..................For large jobs.2. Investment moulding ... Lost wax process.3 Plaster moulding  Mould prepared in 3. Plaster moulding ……… Mould prepared in gypsum.(a) 1, 2 and 3 (b) 1 and 2(c) 1 and 3 (d) 2 and 3

Loam Moulding

Moulding loam is generally artificially composed of

common brick‐clay, and sharp sand.

Loammeans mud.

LoamMoulding is restricted to forms which cannot be

cast conveniently in any other process.

It is costly.

10/9/2011

17

IES‐1997Which one of the following pairs is not correctlymatched?(a) Aluminium alloy piston …………Pressure die casting(b) Jewellery……………………….. Lost wax process(b) Jewellery……………………….. Lost wax process(c) Large pipes ……………………..Centrifugal casting(d) Large bells ………………………Loam moulding

GATE‐1998List I List II (A) Sand casting  (1) Symmetrical and circular shapes only(B) Plaster mould casting  (2) Parts have hardened skins and soft interior(C) Shell mould casting  (3) Minimum post‐casting processing(D) Investment casting  (4) Parts have a tendency     

to warp(5) Parts have soft skin       

and hard interior(6) Suitable only for non‐

ferrous metals

GATE‐1992Match the following moulding/casting processes with the product:Moulding/Casting processes Product(A) Slush casting (P) Turbine blade(B) Shell moulding (Q) Machine tool bed(B) Shell moulding (Q) Machine tool bed(C) Dry sand moulding (R) Cylinder block(D) Centrifugal casting (S) Hollow castings 

like lamp shades(T) Rain water pipe(U) Cast iron shoe brake

GATE‐1996List I List II(A) Rivets for aircraft body  1. Forging(B) Carburettor body  2. Cold heading(C) Crankshafts  3 Aluminium‐based (C) Crankshafts  3. Aluminium‐based 

alloy(D) Nails  4. Pressure die casting

5. Investment casting

IES‐2003Match List I (Products) with List II (Casting Process) and select the correct answer using the codes given below the Lists:List I List II(Products) (Casting Process)A. Hollow statues 1. Centrifugal CastingB Dentures 2 Investment CastingB. Dentures 2. Investment CastingC. Aluminium alloy pistons 3. Slush CastingD. Rocker arms 4. Shell Moulding

5. Gravity Die CastingCodes:A  B  C  D A  B  C  D

(a)  3  2  4  5 (b)  1  3  4  5(c)  1  2  3  4 (d)  3  2  5  4

IES‐1993Match the items of List I (Equipment) with the items of List II (Process) and select the correct answer using the given codes.List I (Equipment)  List II (Process)P ‐ Hot Chamber Machine  1 CleaningP ‐ Hot Chamber Machine  1. CleaningQ ‐Muller  2. Core makingR ‐ Dielectric Baker  3. Die castingS ‐ Sand Blaster  4. Annealing

5. Sand mixing(a) P‐2, Q‐1, R‐4, S‐5  (b) P‐4, Q‐2, R‐3, S‐5(c) P‐4, Q‐5, R‐1, S‐2  (d) P‐3, Q‐5, R‐2, S‐1

10/9/2011

18

IAS‐2004Match List‐I (Name of the Casting Process) with List‐II (Process Definition) and select the correct answer using the codes given below the lists:List‐I List‐II      (Name of the Casting Process) (Process Definition)A. Die casting 1.This process involves use of a mould made of

Dried silica sand and phenolic resin mixtureB El l i    I   hi     l   l i  f d bB. Electroslag casting  2. In this process, molten metal is forced by

Pressure into a metal mouldC. Centrifugal casting  3. This process employs a consumable electrodeD. Precision casting  4. This process involves rotating a mould while the 

metal solidifies5. This process produces very smooth, highlyAccurate castings from both ferrous and nonferrous alloys

Codes:A  B  C  D A  B  C  D(a)  5  4  1  2 (b)  2  3  4  5(c)  5  3  4  2 (d)  2  4  1  5

Q. No Option

1 A2 A3 C4 A5 D

Q. No Option

13 C14 D15 D16 B17 B

Conventional Casting Process  Ch‐21

6 A7 D8 C9 B10 D11 A12 B

18 B19 D20 A21 A

Q. No Option

1 D2 C3 C4 B

Q. No Option

11 A12 A13 D14 A

Special Casting Process  Ch‐22

5 C6 A7 D8 C9 B10 D

14 A15 A16 B17 A