ENGM 445 EXAM QUESTIONS AND
ANSWERS GRADED A+ 2025/2026
When casting low carbon steel under certain mold conditions, the mold constant in Chvorinov's
rule = 4.0 min/cm^2. Determine how long solidification will take for a rectangular casting whose
length = 30 cm, width = 15 cm, and thickness = 20 mm. - ANS 2.78 min
Why must the cross-sectional area at the bottom of the sprue be less than the cross-sectional
area at the top of the sprue during pouring? - ANS In order to ensure that the volume flow
rate of the flowing metal is the same at the top and bottom of the sprue and hence prevent air
from being aspirated into the liquid and conducted into the mold cavity.
Which of the following are some of the factors that affect the fluidity of a molten metal during
pouring into a mold cavity?
a) pouring temperature above the melting point
b) metal alloy composition
c) viscosity of the liquid metal
d) heat transfer to the surroundings
e) a, c, and d
f) all of the above - ANS f) all of the above
What is the limitation of permanent mold casting processes that does not apply to expendable
mold casting processes?
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,a) There is no limitation
b) the need to open the mold to retrieve the part
c) the need to reuse the mold for other similar part
d) b and c - ANS b) the need to open the mold to retrieve the part
The amount by which the mold must be made larger relative to the final casting size is called the
pattern shrinkage allowance. Using Table 10.1, determine the shrinkage allowance to be used by
pattern makers for yellow brass. Express your answer in terms of decimal fraction inches of
elongation per food of length compared to a standard one-foot scale (OR what shrinkage
allowance should be used for a 12 in long yellow brass)? - ANS 0.183 in
A riser in the shape of a sphere is to be designed for a sand casting mold. The casting is a
rectangular plate, with length = 200 mm, width = 100 mm, and thickness = 18 mm. If the total
solidification time of the casting itself is known to be 3.5 min, determine the diameter of the
riser so that it will take 25% longer for the riser to solidify. - ANS 47.5 mm
What is a chaplet? - ANS Chaplets are the supports that hold the core in position within the
mold cavity during pouring.
What properties determine the quality of a sand mold for sand casting?
a) strength
b) permeability
c) thermal stability
d) collapsibility
e) reusability
f) all - ANS f) all
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,What is flash in die casting? - ANS Flash is the liquid metal that squeezes into the small space
between the die halves at the parting line or into the clearances around the cores and ejector
pins.
What are some of the general defects encountered in casting processes? Name and briefly
describe three. - ANS 1. misruns: castings that solidify before the mold cavity has been
completely filled
2. cold shuts: when two portions of the metal flow together but do not fuse together due to the
premature freezing
3. cold shots: castings in which solid globules of metal have formed and become entrapped in
the casting because of splattering during pouring
Investment casting has which two of the following advantages compared to most other casting
processes:
a) close dimensional control
b) high production rates
c) inexpensive process
d) parts of great complexity can be cast
e) parts weighing several tons can be cast
f) a and d
g) a and c - ANS f) a and d
Which two of the following casting processes are expendable mold operations?
a) centrifugal casting
b) die casting
c) investment casting
d) low pressure casting
e) sand casting
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, f) slush casting - ANS c and e: investment casting and sand casting
Wheel and pulleys are examples of castings that are made by
a) centrifuge casting
b) semicentrifugal casting
c) die casting
d) all - ANS b) semicentrifugal casting
A mold shift refers to a defect in sand casting caused by a sidewise displacement of the core
inside the casting before it solidifies.
a) True
b) False - ANS b) False
Which two of the following casting processes are permanent mold operations?
a) centrifugal casting
b) expanded polystyrene process
c) sand casting
d) shell molding
e) slush casting - ANS a and e: centrifugal casting and slush casting
Which one of the following expendable mold processes is known as a precision-casting process?
a) antioch process
b) investment casting
c) plaster-mold casting
d) sand casting
e) shell molding - ANS b) investment casting
4 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
ANSWERS GRADED A+ 2025/2026
When casting low carbon steel under certain mold conditions, the mold constant in Chvorinov's
rule = 4.0 min/cm^2. Determine how long solidification will take for a rectangular casting whose
length = 30 cm, width = 15 cm, and thickness = 20 mm. - ANS 2.78 min
Why must the cross-sectional area at the bottom of the sprue be less than the cross-sectional
area at the top of the sprue during pouring? - ANS In order to ensure that the volume flow
rate of the flowing metal is the same at the top and bottom of the sprue and hence prevent air
from being aspirated into the liquid and conducted into the mold cavity.
Which of the following are some of the factors that affect the fluidity of a molten metal during
pouring into a mold cavity?
a) pouring temperature above the melting point
b) metal alloy composition
c) viscosity of the liquid metal
d) heat transfer to the surroundings
e) a, c, and d
f) all of the above - ANS f) all of the above
What is the limitation of permanent mold casting processes that does not apply to expendable
mold casting processes?
1 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
,a) There is no limitation
b) the need to open the mold to retrieve the part
c) the need to reuse the mold for other similar part
d) b and c - ANS b) the need to open the mold to retrieve the part
The amount by which the mold must be made larger relative to the final casting size is called the
pattern shrinkage allowance. Using Table 10.1, determine the shrinkage allowance to be used by
pattern makers for yellow brass. Express your answer in terms of decimal fraction inches of
elongation per food of length compared to a standard one-foot scale (OR what shrinkage
allowance should be used for a 12 in long yellow brass)? - ANS 0.183 in
A riser in the shape of a sphere is to be designed for a sand casting mold. The casting is a
rectangular plate, with length = 200 mm, width = 100 mm, and thickness = 18 mm. If the total
solidification time of the casting itself is known to be 3.5 min, determine the diameter of the
riser so that it will take 25% longer for the riser to solidify. - ANS 47.5 mm
What is a chaplet? - ANS Chaplets are the supports that hold the core in position within the
mold cavity during pouring.
What properties determine the quality of a sand mold for sand casting?
a) strength
b) permeability
c) thermal stability
d) collapsibility
e) reusability
f) all - ANS f) all
2 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
,What is flash in die casting? - ANS Flash is the liquid metal that squeezes into the small space
between the die halves at the parting line or into the clearances around the cores and ejector
pins.
What are some of the general defects encountered in casting processes? Name and briefly
describe three. - ANS 1. misruns: castings that solidify before the mold cavity has been
completely filled
2. cold shuts: when two portions of the metal flow together but do not fuse together due to the
premature freezing
3. cold shots: castings in which solid globules of metal have formed and become entrapped in
the casting because of splattering during pouring
Investment casting has which two of the following advantages compared to most other casting
processes:
a) close dimensional control
b) high production rates
c) inexpensive process
d) parts of great complexity can be cast
e) parts weighing several tons can be cast
f) a and d
g) a and c - ANS f) a and d
Which two of the following casting processes are expendable mold operations?
a) centrifugal casting
b) die casting
c) investment casting
d) low pressure casting
e) sand casting
3 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
, f) slush casting - ANS c and e: investment casting and sand casting
Wheel and pulleys are examples of castings that are made by
a) centrifuge casting
b) semicentrifugal casting
c) die casting
d) all - ANS b) semicentrifugal casting
A mold shift refers to a defect in sand casting caused by a sidewise displacement of the core
inside the casting before it solidifies.
a) True
b) False - ANS b) False
Which two of the following casting processes are permanent mold operations?
a) centrifugal casting
b) expanded polystyrene process
c) sand casting
d) shell molding
e) slush casting - ANS a and e: centrifugal casting and slush casting
Which one of the following expendable mold processes is known as a precision-casting process?
a) antioch process
b) investment casting
c) plaster-mold casting
d) sand casting
e) shell molding - ANS b) investment casting
4 @COPYRIGHT 2026 ALLRIGHTS RESERVED.
