S i l C iSpecial Castingp g

B   S K M d lBy  S K Mondal

Shell moulding process

IES 2010IES 2010Consider the following advantages of shell 

ld  imould casting:1. Close dimensional tolerance.2. Good surface finish.3  Low cost3. Low cost.4. Easier.Whi h  f  h     ?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     Ans. (c)

IES 1996IES‐1996Consider the following ingredients used inConsider the following ingredients used inmoulding:

1. Dry silica sandy2.Clay3.Phenol formaldehyde3.Phenol formaldehyde4.Sodium silicateThose used for shell mould casting includeThose 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 Ans (c)(c) 1and 3 (d) 1, 2, 3 and 4 Ans. (c)

IES‐2005In shell moulding, how can the shell thickness g,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 h fthe range of 175oC – 380oC

(d) By the type of binder usedAns. (a)

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

Ans  (d)Ans. (d)

IES 2007IES 2007Which of the following are employed in shellmoulding?R i bi d M t l tt H ti il1. Resin binder 2. Metal pattern 3. Heating coils

Select the correct answer using the code givenbelow:below:(a) 1 and 2 only (b) 1 and 3 only(c) 2 and 3 only (d) 1, 2 and 3(c) 2 and 3 only (d) 1, 2 and 3

Ans. (d)( )

IAS 2007IAS‐2007Th ld i h ll ldi i dThe mould in shell moulding process is made up

of which of the following?

(a) Gypsum + setting agents

(b) Green sand + clay

(c) Sodium silicate + dried sand(c) Sodium silicate + dried sand

(d) Dried silica + phenolic resin

Ans. (d)

IAS 1999IAS‐1999Match List I (Moulding Process) with List II (Binding

)g g

Agent) and select the correct answer using the codesgiven below the lists:

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

5. Plastic5. ast cCodes:A B C D A B C D(a) 3 2 5 1 (b) 3 2 4 1( ) (d)(c) 2 3 5 4 (d) 2 3 4 5

Ans. (a)

Fig. Investment flask‐casting procedure

IES 20092 marks

IES 2011IES 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) h k l(d) Stucco coating – Shakeout – Slurry coating – Patternmelt out

A ( )Ans. (c)

GATE 2006GATE‐2006An expendable pattern is used in(a) Slush casting(b) Squeeze casting(c) Centrifugal castingg g(d) Investment castingAns. (d)( )

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

Ans  (c)Ans. (c)

JWM 2010JWM 2010Consider the following materials : W  1. Wax 

2. Wood3. PlasticWhich of these materials can be used as pattern in i   i    ?investment casting process ?(a) 1, 2 and 3  (b) 1 and 2 only(c) 2 and 3 only  (d) 1 and 3 only

Ans. (d)

IES 2010IES 2010Assertion (A): These investment casting is used forprecision parts such as turbine plates sewingprecision parts such as turbine plates, sewingmachines etc.Reason (R): The investment castings have a goodReason (R): The investment castings have a goodsurface finish and are exact reproductions of themaster pattern.p(a) Both A and R are individually true and R is thecorrect explanation of Ap(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 Ans. (a)

IES 2007IES 2007Consider the following statements in respect ofinvestment castings:investment 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?are correct?(a) 1 and 2 only (b) 1 and 3 only(c)2 and 3 only (d) 1 2 and 3(c)2 and 3 only (d) 1, 2 and 3

Ans. (c)

IES 2006IES‐2006Which of the following materials are used forWhich of the following materials are used formaking patterns in investment casting method?1. Wax 2. Rubber 3. Wood 4. Plastic3 4Select the correct answer using the codes given below:(a) Only 1 and 3 (b) Only 2 and 3(a) Only 1 and 3 (b) Only 2 and 3(c) Only 1, 2 and 4 (d) Only 2, 3 and 4

Ans (c)Ans. (c)

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

Ans. (a)

IES 2011IES 2011Consider the following advantages of die casting over sand

ticasting :1. Rapidity of the process2 Smooth surface2. Smooth surface3. Strong dense metal structureWhich of these advantages are correct ?g(a) 1, 2 and 3(b) 1 and 2 only(c) 2 and 3 only(d) 1 and 3 only

A (b)Ans. (b)

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

Ans. (d)

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

Ans. (b)

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

Ans. (c)( )

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

Ans. (c)

IES 1995IES‐1995Assertion (A): An aluminium alloy with 11 % silicon is( ) yused for making engine pistons by die castingtechnique.Reason (R): Aluminium has low density and additionReason (R): Aluminium has low density and additionof silicon improves its fluidity and therefore itscastability.(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 the(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 Ans. (a)

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

graphite iron 2. Gravity die‐castingC. Carburettor housing in aluminium alloy 3. Sand castingg y 3 gD. Cast titanium blades 4. Precision investment 

casting5. Shell moulding

C d A B C D A B C DCode: 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

Ans (a)Ans. (a)

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

Ans. (b)

IAS 1996IAS‐1996Assertion (A): Die casting yields a product of good( ) g y p gaccuracy and finish.Reason (R): Low melting alloys used in die

icasting.(a) Both A and R are individually true and R is thecorrect explanation of Acorrect explanation of A(b) Both A and R are individually true but R is not thecorrect explanation of Ap(c) A is true but R is false(d) A is false but R is true( )

Ans. (b)

IES 2011IES 2011Consider the following statements :

h b h d f d1. Hot chamber machine is used for casting zinc, tin andother low melting alloys.2 Cold chamber machine is used for die casting of ferrous2. Cold chamber machine is used for die casting of ferrousalloys3. Rapid cooling rate in die casting produces high strength

d li i lland quality in many alloys.Which of these statements are correct?(a) 1 2 and 3 (b) 1 and 2 only(a) 1, 2 and 3 (b) 1 and 2 only(c) 2 and 3 only (d) 1 and 3 only

Ans. (d)Ans. (d)

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

i ?casting?(a) Low carbon steel(b) Titanium(c) Copper(d) TinAns. (d)

IES 1995IES‐1995Assertion (A): Aluminium alloys are cast in hot( ) ychamber die casting machine.Reason (R): Aluminium alloys require high

l i h d i llmelting when compared to zinc alloys.(a) Both A and R are individually true and R is thecorrect explanation of Acorrect explanation of A(b) Both A and R are individually true but R is not thecorrect explanation of Ap(c) A is true but R is false(d) A is false but R is true( )

Ans. (d)

Fig. True centrifugal casting

GATE‐2002In centrifugal casting, the impurities are

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

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

Ans (b)Ans. (b)

IES 2008IES‐2008Which of the following casting processes does not/d i l f d i i ?/do not require central core for producing pipe?1. Sand casting process

Di ti2. Die casting process3. Centrifugal casting processSelect the correct answer using the code given below:Select the correct answer using the code given below:(a) 1 and 2(b) 2 only(b) 2 only(c) 2 and 3(d) 3 only Ans (d)(d) 3 only Ans. (d)

IES 2009IES‐2009Whi h f th f ll i ti iWhich one of the following casting processes is

best suited to make bigger size hollow

symmetrical pipes?

( ) Di i(a) Die casting

(b) Investment casting( ) g

(c) Shell moulding

(d) Centrifugal casting Ans. (d)

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

Ans. (a)

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

Ans  (c)Ans. (c)

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

Ans (c)Ans. (c)

IES 2007IES 2007Match List I with List II and select the correct answer using the code given below the Lists: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 refractory

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

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

C d A B C D A B C DCode: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

Ans. (b)

IES 2000IES‐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 CO ldi    N f   llC. CO2 molding  3. Non‐ferrous alloysD. Centrifugal casting  4. Sodium silicate

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

A  (b)Ans. (b)

IAS 2004IAS‐2004M h Li I (N   f  h  P )  i h Li II (Ad )  d  l   h    Match 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. Ceramic mold casting 2.Excellent dimensional accuracy and surface

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

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

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

( )          (d)(c)  2  1  5  3  (d) 4 3 2 1Ans. (d)

Fig. Semi‐centrifugal casting

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

Ans. (a)

Fig. Method of casting by the centrifuging process

IES 2000IES‐2000Match List I (Type of casting) with List II (Working principles) 

d  l t th   t    i  th   d   i  b l  th  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 A. Die casting 1. Molten metal is forced into the die 

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

axis of mouldaxis 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( ) 3 4 ( ) 4 3

Ans. (a)

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

Ans (b)Ans. (b)

IES 2011IES 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

Ans. (a)

IAS 2002IAS‐2002Match List I (Casting Process) with List II (Applications) 

d  l   h       i   h   d   i  b l  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. Pipes. Squee e cast g . pesC. Die Casting 3. Wheels for 

automobiles4 Gear housings4. Gear housings

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

Ans. (a)

IES 1996IES‐1996Which of the following pairs are correctly matched?Which of the following pairs are correctly matched?1. Pit moulding ..................For large jobs.2 Investment moulding  Lost wax process2. Investment moulding ... Lost wax process.3. Plaster moulding ……… Mould prepared in gypsum.gypsum.(a) 1, 2 and 3 (b) 1 and 2(c) 1 and 3 (d) 2 and 3(c) 1 and 3 (d) 2 and 3

Ans. (a)

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

Ans (a) Gravity die castingAns. (a) Gravity die casting

GATE 1998GATE‐1998List I List II (A) Sand casting  (1) Symmetrical and circular shapes only(B) Plaster mould casting  (2) Parts have hardened ( ) g ( )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       (5)

and hard interior(6) Suitable only for non‐

ferrous metalsAns. (A) ‐4, (B) ‐6, (C) ‐2, (D)‐3

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

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

Ans. A – S, B – P, C – R, D – T

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

alloyalloy(D) Nails  4. Pressure die casting

5 Investment casting5. Investment castingAns. (A) – 3, (B) ‐ 4, (C) ‐ 1, (D) – 2

IES 2003IES‐2003Match List I (Products) with List II (Casting Process) and select th   t    i  th   d   i  b l  th  Li tthe correct answer using the codes given below the Lists:List I List II(Products) (Casting Process)A H ll   C if l C iA. Hollow statues 1. Centrifugal 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  4Ans. (d)

IES 1993IES‐1993Match the items of List I (Equipment) with the items ( q p )of List II (Process) and select the correct answer using the given codes.List I (Equipment)  List II (Process)List I (Equipment)  List II (Process)P ‐ Hot Chamber Machine  1. CleaningQ ‐Muller  2. Core makingQ  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( ) (d)(c) P‐4, Q‐5, R‐1, S‐2  (d) P‐3, Q‐5, R‐2, S‐1

Ans. (d)

IAS 2004IAS‐2004Match List‐I (Name of the Casting Process) with List‐II (Process Definition) and select h       i   h   d   i  b l   h  lithe 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 ofA. Die casting 1.This process involves use of a mould made of

Dried silica sand and phenolic resin mixtureB. 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 solidifies Thi     d     th  hi hl5. This process produces very smooth, highly

Accurate castings from both ferrous and nonferrous alloys Ans. (b)

Codes:A  B  C  D A  B  C  DCodes: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