MCQs on Moulding sand
1 - Question
Which of the following is not a principle constituent of molding sand?
a) Silica
b) Aluminum
c) Iron oxide
d) Copper
View Answer
Explanation: Copper is not a principle constituent of molding sand. Moulding sand is generally composed of silica, aluminum, and iron oxide.
2 - Question
When sand is in its natural moist state it is known as?
a) Green sand
b) Facing sand
c) Loam sand
d) Dry sand
View Answer
Explanation: Green sand is a mixture of silica sand with 18-30% clay, having a water content in the range 6-8%. This name got its name “green” in the sense of “not ready” or “not processed” meaning.
3 - Question
Which of the following sand contains clay up to 50% and dries hard?
a) Green sand
b) Facing sand
c) Loam sand
d) Dry sand
View Answer
Explanation: Loam sand contains clay up to 50% and dries hard. It covers less part of mould. This sand is used for loam sand moulds for making very heavy castings usually with the help of sweeps and skeleton patterns. advertisement
4 - Question
Which of the following sand is black in color?
a) Green sand
b) Facing sand
c) Loam sand
d) Backing sand
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Explanation: Backing sand is black in color due to the presence of coal dust or due to burning. It contains mainly of old, used moulding sand which is black in colour due to the presence of coal dust etc on contact with any hot metal.
5 - Question
Which of the following sand is placed next to the surface and comes in contact with the molten metal?
a) Green sand
b) Facing sand
c) Loam sand
d) Backing sand
View Answer
Explanation: Facing sand is placed next to the surface and meets the molten metal. Facing sand is the sand which covers the pattern all around it. The remaining box is filled with ordinary floor sand.
6 - Question
Green strength of sand does not depend upon?
a) Grain size
b) Moisture content
c) Shape and distribution of sand
d) Refractoriness of the sand
View Answer
Explanation: The strength of the sand in green or moist state is termed as green strength. The green sand particles have the ability to cling to each other to impart sufficient strength to the mold.
7 - Question
The strength of the sand which is required to hold the shape of the mould cavity when the metal in the mould is still in liquid form is known as?
a) Hot strength
b) Green strength
c) High strength
d) Refractoriness of the sand
View Answer
Explanation: When the moisture in sand being eliminated, the sand would reach at a high temperature when the metal in the mold is still in liquid state. The strength of the sand that is required to hold the shape of the cavity is called hot strength.
8 - Question
Which of the following will have better plasticity?
a) Coarse sand
b) Fine grained sand
c) Semi grained sand
d) Plasticity does not depend on sand grain size
View Answer
Explanation: Plasticity is the ability of sand particles to undergo unrecoverable deformation at constant volume without cracking and crumbling. Fine grained sand particles will have better plasticity.
9 - Question
The passage of gaseous material, water and steam vapor through the molding sand is known as?
a) Plasticity
b) Flowability
c) Permeability
d) Refractoriness
View Answer
Explanation: The passage of gaseous material, water and steam vapor through the molding sand is known as permeability. Sand which are coarse or have rounded grains exhibit more permeability. In the absence of adequate permeability, defects like surface blows, gas holes, mold blast etc. may be experienced.
10 - Question
Which of the following sand is coated with phenol or urea formaldehyde resins?
a) Shell sand
b) Green sand
c) Dry sand
d) Facing sand
View Answer
Explanation: Shell sand is coated with phenol or urea formaldehyde resins.