Category: Manufacturing Engineering Objective Questions

Manufacturing Engineering Multiple Choice Questions on “Shaper Parts”.

1. Cutting of material during shaping operation takes place in
a) Forward stroke
b) Backward stroke
c) Both forward and backward stroke
d) None of the mentioned
Answer: a
Clarification: Cutting always takes place in forward stroke. Backward stroke is ideal stroke.

2. Which of the following part of shaper supports all of the other parts of machines?
a) Base
b) Column
c) Cross rail
d) Table
Answer: a
Clarification: Base act as support for all other parts. It is made of stronger material.

3. Cutting of material during slotting operation takes place in
a) Forward stroke
b) Backward stroke
c) Both forward and backward stroke
d) None of the mentioned
Answer: a
Clarification: Cutting always takes place in forward stroke. Backward stroke is ideal stroke.

4. Which of the following act as housing for an operating mechanism in shaper?
a) Base
b) Column
c) Cross rail
d) Table
Answer: b
Clarification: Column acts as housing for operating mechanism in shaper. It is made of stronger material.

5. Which of the following part of shaper machine carries table elevating mechanism?
a) Base
b) Column
c) Cross rail
d) Table
Answer: c
Clarification: Cross rail carries table elevating mechanism. It is used to raise the of the table.

6. Which of the following part of shaper machine carries vertical guide ways mechanism?
a) Base
b) Column
c) Cross rail
d) Table
Answer: c
Clarification: Cross rail carries vertical guide ways mechanism. Cross rail carries table elevating mechanism. It is used to raise the of table.

7. Which of the following part of shaper machine hold and supports the work piece?
a) Base
b) Column
c) Cross rail
d) Table
Answer: d
Clarification: Table supports work piece. It is made of harder material.

8. Which of the following part of shaper machine carries tool head?
a) Cross rail
b) Column
c) Ram
d) Table
Answer: c
Clarification: Ram carries tool head. It also carries mechanism for tool head movement.

9. Which of the following part of shaper provides straight line motion of tool?
a) Cross rail
b) Column
c) Ram
d) Table
Answer: c
Clarification: Ram carries tool head and provides straight line motion to a tool.

10. Which of the following part of shape is used to hold the tool?
a) Cross rail
b) Tool head
c) Ram
d) Vice
Answer: b
Clarification: Tool head is used for tool holding purpose. It is attached to ram.

11. Which of the following can be used as job holding device in shaping machine?
a) Cross rail
b) Column
c) Ram
d) Vice
Answer: d
Clarification: Vice is a job holding device. It have good efficiency as holding device.

Manufacturing Engineering Multiple Choice Questions on “Grinding Wheel-1”.

1. Grain number of grinding wheel is ___ to grain size.
a) Directly proportional
b) Inversely proportional
c) Does not depend
d) None of the mentioned
Answer: b
Clarification: Grain number = 1/(grain size). Grain number is similar to density of grains on grinding wheels.

2. Which of the following is a correct range for grain number of the grinding wheel for coarse grains?
a) 220-600
b) 80-180
c) 30-60
d) 10-24
Answer: d
Clarification: For coarse grain, grain number ranges from 10 to 24.

3. Which of the following is the correct range for grain number of the grinding wheel for medium grains?
a) 220-600
b) 80-180
c) 30-60
d) 10-24
Answer: c
Clarification: For medium grain, grain number ranges from 30 to 60.

4. Which of the following is a correct range for grain number of the grinding wheel for fine grains?
a) 220-600
b) 80-180
c) 30-60
d) 10-24
Answer: b
Clarification: For fine grains, grain number ranges from 80 to 180.

5. Which of the following is the correct range for grain number of the grinding wheel for very fine grains?
a) 220-600
b) 80-180
c) 30-60
d) 10-24
Answer: a
Clarification: For very fine grains, grain number ranges from 220 to 600.

6. Which of the following grinding machine will give a better result for rough machining?
a) Fine grain
b) Very fine grain
c) Coarse grain
d) None of the mentioned
Answer: c
Clarification: Coarse grain wheel will give better metal removal rate and space for chip removal as rate of chip flow in rough machining is high.

7. Which of the following grinding machine will give a better result for finish machining operation?
a) Fine grain
b) Medium grain
c) Coarse grain
d) None of the mentioned
Answer: c
Clarification: Fine grain wheel will give smaller metal removal rate and hence better for finishing operations.

8. Which of the following symbol’s range of alphabet represent soft grain in grinding wheel?
a) A – H
b) I – P
c) Q – T
d) T – Z
Answer: a
Clarification: A-H represents soft grains in grinding wheel.

9. Which of the following symbol’s range of alphabet represent medium hardness grain in grinding wheel?
a) A – H
b) I – P
c) Q – T
d) T – Z
Answer: b
Clarification: I-P represents medium hard grains in grinding wheel.

10. Which of the following symbol’s range of alphabet represent hard grain in grinding wheel?
a) D – H
b) I – P
c) A – D
d) Q – Z
Answer: a
Clarification: A-H represents soft grains in grinding wheel.

Manufacturing Engineering Multiple Choice Questions on “Gas Welding and Gas Cutting”.

1. Which of the following is also called “gas welding”?
a) Oxy fuel gas welding
b) Metallic welding
c) Arc welding
d) Fuel gas welding
Answer: a
Clarification: Gas welding is also known as oxy fuel gas welding. In gas welding, fuel gases are used to generate high amount of heat and melt the metal.

2. How many types of flames are there in welding?
a) 1
b) 2
c) 3
d) 4
Answer: c
Clarification: There are three basic flame types: neutral (balanced), excess acetylene (carburizing), and excess oxygen (oxidizing) as shown below.

3. In which of the following type of flame, oxygen is of same proportion with acetylene?
a) Neutral flame
b) Oxidizing flame
c) Carburizing flame
d) Both oxidizing flame and carburizing flame
Answer: a
Clarification: In neutral flame oxygen is in the same proportion with acetylene. Neutral welding flames are commonly used to weld: mild steel, stainless steel, cast iron, copper, aluminium, etc.

4. In which of the following type of flame, oxygen is in excess proportion with acetylene?
a) Neutral flame
b) Oxidizing flame
c) Carburizing flame
d) Both oxidizing flame and carburizing flame
Answer: b
Clarification: Oxidizing welding flames are produced when slightly more than one volume of oxygen is mixed with one volume of acetylene. Oxidizing welding flames are commonly used to weld zinc, copper, manganese steel, cast iron, etc.

5. In which of the following type of flame, oxygen is deficient in proportion with acetylene?
a) Neutral flame
b) Oxidizing flame
c) Carburizing flame
d) Both oxidizing flame and carburizing flame
Answer: c
Clarification: The carburizing flame has excess acetylene then oxygen. Reducing flame is used for the welding of low carbon and alloy steel.

6. Which of the following flame is harmful to steel?
a) Neutral flame
b) Oxidizing flame
c) Carburizing flame
d) Both oxidizing flame and carburizing flame
Answer: b
Clarification: Oxidizing flame is harmful to steel. An oxidizing flame should not be used for welding steel because the deposited metal will be porous, oxidized and brittle. This flame will ruin most metals and should be avoided.

7. For brazing, soldering and flame hardening which of the following flame is used?
a) Neutral flame
b) Oxidizing flame
c) Carburizing flame
d) Both oxidizing flame and carburizing flame
Answer: c
Clarification: For brazing, soldering and flame hardening carburizing flame is used.

8. The inner cone of the flame in welding has the following nature?
a) Highest temperature
b) Coldest temperature
c) Moderate temperature
d) Uncertain
Answer: a
Clarification: The inner cone of the flame has the highest temperature (3500°C). The outer flame has the lowest temperature.

9. The oxy acetylene gas welding is a type of?
a) Endothermic reaction
b) Exothermic reaction
c) Neutral reaction
d) Both endothermic reaction and exothermic reaction
Answer: b
Clarification: The oxy acetylene gas welding is a type of exothermic reaction. 1 mole of acetylene can produce KJ/mol of heat.

10. The chemical formula of acetylene is?
a) C₂H₄
b) C₂H₆
c) C₂H₅OH
d) C₂H₂
Answer: d
Clarification: The chemical formula of acetylene is C₂H₂. 1 mole of acetylene can produce KJ/mol of heat.

Manufacturing Engineering Multiple Choice Questions on “Various Casting Process”.

1. Injection moulding is not a type of?
a) Die casting
b) Centrifugal casting
c) Squeeze casting
d) Investment casting
Answer: a
Clarification: In casting processes, there are two type of mould processes: 1. expendable mould processes, 2. permanent mould processes. Casting types such as, low-pressure PM casting, vacuum PM casting, die casting, squeeze casting, centrifugal casting, semi-centrifugal casting, injection moulding and compression moulding comes under permanent mould processes. Likewise, sand casting, shell casting, plaster casting, ceramic casting and investment casting are the types of expendable mould processes.

2. Which of the following statement is not correct about die casting?
a) It has close dimensional accuracy
b) Die has good life
c) It is very economical for large scale production
d) No need for removing the entrapped gases
Answer: d
Clarification: Gas entrapment is a very serious defect in all casting processes, and die casting too can go without them.

3. Which type of casting is preferred for making hollow pipes and tubes which are axisymmetric with concentric holes?
a) Centrifuging
b) True centrifugal casting
c) Semi-centrifugal casting
d) None of the mentioned
Answer: b
Clarification: Centrifugal casting is used to make hollow pipes. In this process, molten metal is poured in a mould which is rotating. The molten metal experiences centrifugal force and it is forced radially outward. The axis of rotation could be vertical, horizontal, or even inclined.

4. Which of the following casting is a combination of casting and forging?
a) Die casting
b) Centrifugal casting
c) Squeeze casting
d) Investment casting
Answer: c
Clarification: Squeeze casting is a combination of casting and forging. It is a process in which an alloy melt solidifies under the application of external pressure, in order to prevent the formation of shrinkage porosity.

5. In plaster mould casting the mould is made from?
a) CaSO₄
b) CaSO₃
c) CaSO₂
d) Ca(SO₄)₂
Answer: a
Clarification: The mould is made from plaster of Paris whose chemical formula is CaSO₄ Where Ca is calcium, S is sulphur and O represents oxygen.

6. In which casting process the sand is mixed with a thermosetting resin to form a mould?
a) Die casting
b) Centrifugal casting
c) Squeeze casting
d) Shell moulding
Answer: d
Clarification: The first step in the shell mold casting process is to manufacture the shell mold. The sand we use for the shell molding process is of a much smaller grain size than the typical greensand mold. This fine-grained sand is mixed with a thermosetting resin binder.

7. Which one of the following is a resin used in shell moulding technique?
a) Diphenyl aldehyde
b) Phenol formaldehyde
c) Methyl formaldehyde
d) Dimethyl formaldehyde
Answer: b
Clarification: Phenol formaldehyde and phenol formaldehyde are the two synthetic thermosetting resins used in shell moulding process.

8. Which casting is used to make hollow casting with thin walls?
a) Die casting
b) Centrifugal casting
c) Slush casting
d) Shell moulding
Answer: c
Clarification: Slush casting creates hollow castings with thin walls. This process gives thin-walled profiles with a superior surface finish.

9. In investment casting process which of the following is used for pattern making?
a) Ceramics
b) Molten wax
c) Silica
d) Plaster of paris
Answer: b
Clarification: Investment casting refers to the material being surrounded by a refractory material which is expendable, usually a ceramic. The wax carving is “invested” in the refractory material so to speak. Lox wax refers to a wax shape being made then surrounded with the refractory material to create a mold. The molten metal is then poured in the mold which melts the wax. As the wax runs out of the mold then the molten metal assumes the shape left by the impression of the wax object.

10. Which of the following is not an example of a precision casting process?
a) Plastic mould casting
b) Ceramic mould casting
c) Slush casting
d) Investment casting
Answer: d
Clarification: Precision casting is a lox wax casting (investment casting) process. The lox was method of precision casting is suitable for producing casting with complex shapes and high dimensional accuracy.

Manufacturing Engineering Multiple Choice Questions on “Foundries and Foundry Automation”.

1. Which of the following furnaces, are used extensively in foundries and have such advantages as a high rate of melting?
a) Induction
b) Electric arc
c) Crucible
d) Vacuum arc
Answer: b
Clarification: Electric-arc furnaces, are used extensively in foundries and have such advantages as a high rate of melting (and thus high-production rate), much less pollution than other types of furnaces, and the ability to hold the molten metal for alloying purposes.

2. Which of the following furnaces, are especially useful in smaller foundries?
a) Induction
b) Electric arc
c) Crucible
d) Vacuum arc
Answer: a
Clarification: Induction furnaces, are especially useful in smaller foundries and produce smaller Composition-controlled melts.

3. Which of the following furnace consists of a crucible completely surrounded with a water-cooled copper coil?
a) coreless induction
b) electric arc
c) channel
d) vacuum arc
Answer: a
Clarification: The coreless induction furnace consists of a crucible surrounded with a water-Cooled copper coil through which a high-frequency current pass. Because there is a strong electromagnetic stirring action during induction heating, this type of furnace has excellent mixing characteristics for alloying and adding a new charge of metal.

4. Which of the following furnaces uses a low-frequency current?
a) coreless induction
b) electric arc
c) channel
d) vacuum arc
Answer: c
Clarification: The channel furnace, uses a low-frequency Current (as low as 60 Hz) and has a coil that surrounds only a small portion of the unit.

5. Channel furnaces are used in?
a) superheating
b) holding
c) duplexing
d) all of the mentioned
Answer: d
Clarification: Channel furnace are used in nonferrous foundries and are particularly suitable for (a) superheating (that is, heating above normal Casting temperature to improve fluidity), (b) holding (which makes it suitable for die-casting applications), and (c) duplexing (using two furnaces-for instance, melt the metal in one furnace and transfer it to another).

6. Which of the following furnaces are heated with various fuels, such as commercial gases, fuel oil, and fossil fuel, as well as electricity?
a) Induction
b) Electric arc
c) Crucible
d) Vacuum arc
Answer: c
Clarification: Crucible furnaces, which have been used extensively throughout history, are heated with various fuels, such as commercial gases, fuel oil, and fossil fuel, as well as electricity. Crucible furnaces may be stationary, tilting, or movable.

7. Which of the following furnaces are basically vertical, refractory-lined steel vessels charged with alternating layers of metal, coke, and flux?
a) Cupolas
b) Electric arc
c) Crucible
d) Vacuum arc
Answer: a
Clarification: Cupolas are basically vertical, refractory-lined steel vessels charged with alternating layers of metal, coke, and flux. Although they require major investments and increasingly are being replaced by induction furnaces, cupolas operate continuously, have high melting rates, and produce large amounts of molten metal.

8. Which of the following technique involves magnetic suspension of the molten metal?
a) Cupolas
b) Levitation melting
c) Crucible
d) Induction melting
Answer: b
Clarification: Levitation melting involves magnetic suspension of the molten metal. An induction coil simultaneously heats a solid billet and stirs and confines the melt, thus eliminating the need for a crucible.

9. Which of the following is correct regarding “automation” in industry?
a) reduces the possibility of human error
b) minimizes labour cost
c) increases the production rate
d) all of the mentioned
Answer: d
Clarification: Automation minimizes labor, reduces the possibility of human error, increases the production rate, and attains higher quality levels.

10. Industrial robots are used in foundry operations for ___________
a) cleaning
b) riser cutting
c) mold venting
d) all of the mentioned
Answer: d
Clarification: Industrial robots are now used extensively in foundry operations, such as cleaning, riser cutting, mold venting, mold spraying, pouring, sorting, and inspection.

Manufacturing Processes Multiple Choice Questions on “Roll Forming – 3”.

1. During roll forming, a flat strip is passed number of times through the rollers.
a) True
b) False
Answer: a
Clarification: In roll forming, a flat strip is gradually formed to the finished shape. The forming is almost exclusively accomplished by rotating contoured rolls while the material passes through the mill.

2. Which of following is necessary in order to have a good set of rolls?
a) Short horizontal distances
b) Small lead-in flanges
c) A smooth flow of material
d) Less number of forming passes
Answer: c
Clarification: The probability of having a good set of rolls is to follow few rules:
(1) Envision a smooth flow of material,
(2) Do not be skimpy with the number of forming passes,
(3) Avoid too short horizontal distances and too small lead-in flanges.

3. Which of the following is true in case of “too quick” forming (too few passes)?
a) It makes the tooling and the process uneconomical
b) It makes process easier
c) It distorts the product
d) Eliminate the need of a skilled operator
Answer: c
Clarification: “Too quick” forming (too few passes) will distort the product because of the unacceptable level of stresses generated in the metal. On the other hand, too many passes will make the tooling and the process uneconomical.

4. What is “leg length” or “leg ”?
a) The maximum vertical dimension of the profile
b) Total length of the product
c) Excess length of the product
d) Maximum of the section
Answer: a
Clarification: The depth of the section, also called as “leg length” or “leg ”, is the maximum vertical dimension of the profile as it exits from the last pass. Sometimes it called as “depth of corrugation”.

5. In case of “U” channel/ section, the length of travel of the edge of the strip (effective length of the strip) ‘s’, travelling in a helical pattern having initial length ‘l’ is given by_____
a) l² = s² + c²
b) c² = l² + s²
c) s² = l² + c²
d) s = l² + c²
Answer: c
Clarification: As we know, edge of the strip to be bend travels in a helical path, the length of the strip after bending is given by formula:
s² = l² + c², where, s = final length &
l = initial length.

6. What will be the elongation if a 1in high section is formed in four passes in a mill having a horizontal distance (between passes) of 14in?
a) 0.04%
b) 0.16%
c) 0.63%
d) 0.50%
Answer: a
Clarification: Here, h = 1in; number of passes = 4 and each of length = 14in
Therefore, l = 4 * 14 = 56.

Therefore,
Elongation, e = (56.022 – 56)/ 56
= 0.0004 = 0.04%.