Special Casting Fig Q a for Students

Sp i l C i g Special Casting B   S K M d l By  S K Mondal

Shell moulding process

IES 2010 IES 2010 Consider the following advantages of shell  mould casting: ld  i 1. Close dimensional tolerance. 2. Good surface finish. 3  Low cost 3. 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 1996 IES‐1996 Consider the following ingredients used in moulding: 1. Dryy silica sand 2.Clay 3.Phenol formaldehyde 4.Sodium silicate Those used for shell mould casting include (a) 1, 2 and 4 (b) 2, 3 and 4 (c) 1and 3 (d) 1, 1 2, 2 3 and 4 Ans. Ans (c)

IES‐2005 g, In 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  oC – 380oC the range of 175 h f (d) By the type of binder used Ans. (a)

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

IES 2007 IES 2007 Which of the following are employed in shell moulding? 1. Resin R i binder bi d 2. Metal M t l pattern tt 3. Heating H ti coils il Select the correct answer using the code given below: (a) 1 and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1, 2 and 3 Ans. (d) ( )

IAS 2007 IAS‐2007 The process is Th mould ld in i shell h ll moulding ldi i made d up of which of the following? (a) Gypsum + setting agents (b) Green sand + clay (c) Sodium silicate + dried sand (d) Dried silica + phenolic resin Ans. (d)

IAS 1999 IAS‐1999 g Process) with List II (Binding g Match List I (Moulding Agent)) and select the correct answer using the codes given below the lists: List I List II A. Green sand 1. Silicate B. Core sand 2. Organic C Shell C. Sh ll moulding ldi 3. Clay Cl D. CO2 process 4. Plaster of Paris 5. Plastic ast c Codes:A B C D A B C D (a) 3 2 5 1 (b) 3 2 4 1 ( ) 2 (c) 3 5 4 (d) 2 3 4 5 Ans. (a)

Fig. Investment flask‐casting procedure

IES 2009 y 2 marks

IES 2011 IES 2011 The proper sequence of investment casting steps is : (a) Slurry coating – pattern melt out‐Shakeout – Stucco coating (b) Stucco coating – Slurry coating – Shakeout – Pattern melt out (c) Slurry coating – Stucco coating – Pattern melt out – Shakeout (d) Stucco coating – Shakeout h k – Slurry l coating – Pattern melt out A (c) Ans. ( )

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

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

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

IES 2010 IES 2010 Assertion (A): These investment casting is used for precision parts such as turbine plates, plates sewing machines etc. Reason (R): The investment castings have a good surface finish and are exact reproductions of the master pattern. p (a) Both A and R are individually true and R is the correct explanation p 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 Ans. (a)

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

IES 2006 IES‐2006 Which of the following materials are used for making patterns in investment casting method? 2. Rubber 33. Wood 4. Plastic 4 1. Wax 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 Ans (c) Ans.

IAS 1996 IAS‐1996 Light and intricate parts with close dimensional tolerances of the order of ± 0.005 mm are produced by (a) Investment casting ((b)) Die casting g (c) Centrifugal casting ((d)) Shell mould casting g Ans. (a)

IES 2011 IES 2011 Consider the following advantages of die casting over sand casting ti : 1. Rapidity of the process 2 Smooth surface 2. 3. Strong dense metal structure Which of these advantages g are correct ? (a) 1, 2 and 3 (b) 1 and 2 only (c) 2 and 3 only (d) 1 and 3 only A (b) Ans.

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

JWM 2010 JWM 2010 Assertion (A) : In die casting method, small thickness can be filled with liquid metal. metal Reason (R) : The air in die cavity trapped inside the casting causes problems. problems (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 Ans. (b)

IES 2005 IES‐2005 Which one of the following processes produces a casting when pressure forces the molten metal into the mould cavity? (a) Shell moulding (b) Investment casting ((c)) Die casting g ((d)) Continuous casting g Ans. (c) ( )

IES 2006 IES‐2006 In which of the following are metal moulds used? (a) Greensand mould (b) Dry sand mould (c) Die casting process (d) Loam moulding Ans. (c)

IES 1995 IES‐1995 ) An aluminium alloy y with 11 % silicon is Assertion ((A): used for making engine pistons by die casting technique. Reason (R): Aluminium has low density and addition of silicon improves its fluidity and therefore its castability. (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 Ans. (a)

IES 1995 IES‐1995 Match 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 A. Automobile piston in aluminium alloy 1  Pressure die‐casting 1. Pressure die casting B. Engine crankshaft in spheroidal graphite iron 2. Gravity die‐casting C. Carburettor housing in aluminium g alloyy 33. Sand casting g D. Cast titanium blades 4. Precision investment  casting 5. Shell moulding C d 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 Ans (a) Ans.

IAS 2007 IAS‐2007 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? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 Ans. (b)

IAS 1996 IAS‐1996 ) Die casting gy Assertion ((A): yields a p product of g good accuracy and finish. Reason (R): Low melting alloys used in die casting. i (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 p of A (c) A is true but R is false ((d)) A is false but R is true Ans. (b)

IES 2011 IES 2011 Consider the following statements : 1. Hot chamber is used h b machine h d for f casting zinc, tin and d other low melting alloys. 2 Cold chamber machine is used for die casting of ferrous 2. alloys 3. Rapid cooling rate in die casting produces high strength and d quality li in i many alloys. ll Which of these statements are correct? (a) 1, 1 2 and 3 (b) 1 and 2 only (c) 2 and 3 only (d) 1 and 3 only Ans. (d)

GATE 2007 GATE‐2007 Which of the following engineering materials is the most suitable candidate for hot chamber die casting? i ? (a) Low carbon steel (b) Titanium (c) Copper (d) Tin Ans. (d)

IES 1995 IES‐1995 ) Aluminium alloys y are cast in hot Assertion ((A): chamber die casting machine. Reason (R): Aluminium alloys require high melting l i when h compared d to zinc i alloys. ll (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 p of A (c) A is true but R is false ((d)) A is false but R is true Ans. (d)

Fig. True centrifugal casting

GATE‐2002 In centrifugal casting, the impurities are (a) Uniformly distributed (b) Forced towards the outer surface pp near the mean radius of the casting g (c) Trapped (d) Collected at the centre of the casting ( ) Ans. (d)

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

IES 2008 IES‐2008 Which of the following casting processes does not /do /d not require i centrall core for f producing d i pipe? i ? 1. Sand casting process 2. Die Di casting ti process 3. Centrifugal casting process Select the correct answer using the code given below: (a) 1 and 2 (b) 2 only (c) 2 and 3 (d) 3 only Ans (d) Ans.

IES 2009 IES‐2009 Which casting processes is Whi h one off the th following f ll i ti i best

suited

to

make

bigger

size

hollow

symmetrical pipes? ( ) Die (a) Di casting i ((b)) Investment casting g (c) Shell moulding (d) Centrifugal casting

Ans. (d)

IES 2007 IES 2007 Which one of the following is the correct statement? g casting g method In a centrifugal (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 Ans. (a)

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

IES 2009 IES‐2009 Which of the following are the most likely characteristics in centrifugal casting? ((a)) Fine g grain size and high g p porosityy (b) Coarse grain size and high porosity (c) Fine grain size and high density (d) Coarse grain size and high density Ans (c) Ans.

IES 2007 IES 2007 Match 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 mould B. 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  a metallic mould   lli   ld D. Centrifugal casting 4. After cooling, the invest is removed  from the Casting by pressure jetting or  vibratory cleaning C d A Code: 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 2000 IES‐2000 Match List I (Process) with List II (Products/materials)  and select the correct answer using the codes given  below the Lists: List I  List II A. Die casting  1. Phenol formaldehyde B. Shell molding  2. C.I. pipes C CO2 molding  C. ldi   3. Non‐ferrous alloys  N f   ll D. Centrifugal casting  4. Sodium silicate Codes:A Codes: B  B C  C D  D A  B  B C  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 2004 IAS‐2004 Match List‐I (Name of the Process) with List‐II (Advantage) and select the correct  M h Li I (N   f  h  P )  i h Li II (Ad )  d  l   h     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 quality B. Ceramic mold casting 2.Excellent dimensional accuracy and surface finish g 33. Intricate shapes and close tolerance parts p p C. Die casting D. Centrifugal casting 4. Almost any metal is cast and there if no limit to size, shape and weight 5. Good dimensional accuracy, finish and low porosity Codes:A  B  C  D A  B  C  (a)  2  3  5  1 (b) 4  1 2 ((c)  )  Ans. (d)

2  

1  

5  

3  

(d)

4

3

2

D 3 1

Fig. Semi‐centrifugal casting

IAS 2003 IAS‐2003 ) Semi‐centrifugal g g p Assertion ((A): casting process is similar to true centrifugal casting except that the central core is used in it to form inner surface. Reason (R): In semi‐centrifugal semi centrifugal casting process the axis of spin is always vertical ((a)) Both A and R are individuallyy 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 Ans. (a)

Fig. Method of casting by the centrifuging process

IES 2000 IES‐2000 Match List I (Type of casting) with List II (Working principles)  and select the correct answer using the codes given below the  d  l t th   t    i  th   d   i  b l  th   Lists: List I List II A A. Die casting 1  Molten metal is forced into the die  1. Molten metal is forced into the die  under pressure B. Centrifugal casting 2. Axis of rotation does not coincide with  axis of mould C.  Centrifuging 3. Metal solidifies when mould is rotating D. Continuous casting 4. Continuously pouring molten metal  into mould Codes: A B C  D A B  C D (a)  1  3  2  4  (b)  4  3  2  1 ((c)  ) 1  2  33  4  4 ((d)  ) 4  4 2  33  1 Ans. (a)

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

IES 2011 IES 2011 The method of casting for producing ornamental pieces are: (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 2002 IAS‐2002 Match List I (Casting Process) with List II (Applications)  and select the correct answer using the codes given below  d  l   h       i  h   d   i  b l   the Lists: List I  List II (Casting Process)  (Applications) A. Centrifugal casting 1. Carburetor B.. Squee Squeeze casting e cast g 2.. Pipes pes C. Die Casting 3. Wheels for  automobiles 4 4. Gear housings Codes:  A B C A B C (a)  2 3 1 (b)  4 1 3 ( )  2 (c)  1 3 (d)  4 3 1 Ans. (a)

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

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

GATE 1998 GATE‐1998 List I (A) Sand casting  (1) shapes only ((B)) Plaster mould casting  g skins and soft interior (C) Shell mould casting  (3) processing (D) Investment casting  (4)

Ans. (A) ‐4, (B) ‐6, (C) ‐2, (D)‐3

List II  Symmetrical and circular  ((2))

Parts have hardened 

Minimum post‐casting  Parts have a tendency                   to warp (5) Parts have soft skin        and hard interior (6) Suitable only for non‐ ferrous metals

GATE 1992 GATE‐1992 g g gp Match the following moulding/casting processes with  the product: Moulding/Casting processes Product (A) Slush casting Sl h  i (P) T bi  bl d (P) Turbine blade (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  b k brake Ans. A – S, B – P, C – R, D – T

GATE 1996 GATE‐1996 List I List II (A) Rivets for aircraft body  1. Forging (B) Carburettor body  2 2. Cold heading (C) Crankshafts  3. Aluminium‐based  alloy (D) Nails  4. Pressure die casting 5 5. Investment casting Ans. (A) – 3, (B) ‐ 4, (C) ‐ 1, (D) – 2

IES 2003 IES‐2003 Match List I (Products) with List II (Casting Process) and select  the correct answer using the codes given below the Lists: th   t    i  th   d   i  b l  th  Li t List I List II (Products) (Casting Process) A A. H ll   Hollow statues 1. C Centrifugal Casting if l C i B. Dentures 2. Investment Casting C. Aluminium alloy pistons 3. Slush Casting D. Rocker arms 4. Shell Moulding 5. Gravity Die Casting Codes: 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 y Ans. (d)

IES 1993 IES‐1993 ( q p ) Match 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. Cleaning Q ‐ Muller  Q  2. Core making R ‐ Dielectric Baker  3. Die casting S ‐ 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 ( ) P‐4, Q‐5, R‐1, S‐2  (c) (d) P‐3, Q‐5, R‐2, S‐1 Ans. (d)

IAS 2004 IAS‐2004 Match List‐I (Name of the Casting Process) with List‐II (Process Definition) and select  the correct answer using the codes given below the lists: h       i  h   d   i  b l   h  li 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 mixture B. Electroslag casting  2. In this process, molten metal is forced by Pressure into a metal mould C. Centrifugal casting  3. This process employs a consumable electrode D. Precision casting  4. This process involves rotating a mould while the  metal solidifies 5. This process produces very smooth, highly  Thi     d     th  hi hl Accurate castings from both ferrous and non ferrous alloys Ans. (b) 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