Casting, Forming and Welding Questions and Answers Part-12

1. How much should fuel oil be added to increase the moulding ability of sand?
a) 0.01% – 0.1%
b) 0.02% – 0.2%
c) 0.03% – 0.3%
d) 0.04% – 0.4%

Answer: a
Explanation: Fuel oils are known to have great properties in them. Fuel oils are helpful in adding to the increase of the moulding ability of sand. It can be added in the range of 0.01% to 0.1%.

2. In the green sand moulding of steel casting, what is the bentonite percentage composition?
a) 1.5%
b) 2.5%
c) 3.5%
d) 4.5%

Answer: c
Explanation: In green sand mouldings of steel castings, the dextrin percentage is quite lower, it is around 0.5%. The bentonite percentage composition in green sand molding is calculated to be 3.5%.

3. In the green sand moulding of steel casting, what is the dextrine percentage composition?
a) 0.5%
b) 1.5%
c) 2.5%
d) 3.5%

Answer: a
Explanation: In green sand mouldings of steel castings, the dextrine percentage composition is calculated to be 0.5% and the bentonite percentage in the same green sand is higher than dextrin by around 3%.

4. In the green sand moulding of steel casting, what is the moisture percentage composition?
a) 1% – 2%
b) 2% – 3%
c) 3% -4%
d) 4% – 5%

Answer: c
Explanation: In green sand mouldings of steel castings, the moisture percentage composition is calculated to be 3%- 4% and the amount of bentonite present in the same green sand is around 3.5%.

5. In dry sand moulding of steel casting, what is the bentonite percentage composition?
a) 1%
b) 2%
c) 4%
d) 5%

Answer: d
Explanation: In dry sand mouldings of steel castings, the bentonite percentage composition is calculated to be 5% and in green sand, the bentonite percentage is calculated to be 3.5%.

6. In dry sand moulding of steel casting, what is the dextrine percentage composition?
a) 0.5%
b) 1.5%
c) 2.5%
d) 3.5%

Answer: a
Explanation: In dry sand mouldings of steel castings, the dextrine percentage composition is calculated to be 0.5%. In green sands, the dextrin content is also 0.5%, which is in green sand and in dry sand, the percentage of dextrine is same.

7. In green sand moulding of steel casting, what is the moisture percentage composition?
a) 2-3%
b) 3-4%
c) 4-5%
d) 5-6%

Answer: d
Explanation: In dry sand mouldings of steel castings, the moisture percentage composition is calculated to be 5-6%. In green sands, the moisture content is relatively lower than dry sands. It is around 3% to 4%.

8. In synthetic sands of aluminium alloys, what is the bentonite percentage composition?
a) 2-5%
b) 3-5%
c) 4-5%
d) 5-6%

Answer: c
Explanation: In synthetic sands of aluminium alloys, the bentonite percentage composition is calculated to be 4-5%. Whereas, in the case of green sands, the bentonite percentage is recorded to be around 3.5%.

9. In gray iron castings of facing sand mixtures, what is the bentonite percentage composition?
a) 2-3%
b) 3-4%
c) 4-5%
d) 5-6%

Answer: a
Explanation: In gray cast irons of facing sand mixtures, the bentonite percentage composition is calculated to be 2-3%. Whereas, in the case of green sands, the bentonite percentage is recorded to be around 3.5%

10. In magnesium alloys, what is the bentonite percentage composition?
a) 1%
b) 2%
c) 3%
d) 4%

Answer: d
Explanation: In magnesium alloys, the bentonite percentage composition is calculated to be 4%. Whereas, in the case of green sands, the bentonite percentage is recorded to be around 3.5%.