Casting, Forming and Welding Multiple Choice Questions & Answers (MCQs) on “Coke Bed Charge Calculations”.
1. Given: cupola diameter = 65cm, Height of groove = 135cm, coke density = 490kg/m3. Find mass of bed charge.
a) 234.7 kg
b) 219.5 kg
c) 209.5 kg
d) 216.5 kg
Answer: b
Clarification: According to the question, d = 65cm = 0.65m, h = 135cm = 1.35m, w = 490 kg/m3. Therefore, according to the formula, W = π/4 x d2 x h x w => W = π/4 x 0.652 x 1.35 x 490 => W = 219.5 kg.
2. Given: cupola diameter = 35cm, mass of bed charge = 300kg, coke density = 505kg/m3. Find height of groove.
a) 6.1 m
b) 5.8 m
c) 3.6 m
d) 7.2 m
Answer: a
Clarification: In this question, d = 35cm = 0.35m, w = 505 kg/m3, W = 300kg. Therefore, according to the formula, W = π/4 x d2 x h x w, => h= 300 / (π/4 x 0.352 x 505) => h = 6.1m.
3. Given: cupola diameter = 45cm, mass of bed charge = 325kg, height of groove = 6.5m. Find coke density.
a) 314.38 kg/m3
b) 309.54 kg/m3
c) 193.92 kg/m3
d) 340.57 kg/m3
Answer: a
Clarification: Here, d = 45cm = 0.45m, W = 325kg, height of groove, h = 6.5m. Therefore, according to the formula, W = π/4 x d2 x h x w, => w= 325 / (π/4 x 0.452 x 325 x 6.5) => w = 314.38 kg/m3.
4. What is the minimum efficiency, in general of a cupola?
a) 15%
b) 30%
c) 25%
d) 35%
Answer: b
Clarification: The minimum efficiency of a cupola is 30%, and that, the maximum efficiency is 50%. Hence, the efficiency ranges from 30 to 50% only.
5. Given: cupola diameter = 50cm, Height of groove = 155cm, coke density = 480kg/m3. Find mass of bed charge.
a) 146 kg
b) 148 kg
c) 156 kg
d) 164 kg
Answer: a
Clarification: Here, d = 50cm = 0.5m, h = 155cm = 1.55m, w = 480 kg/m3. Therefore, according to the formula, W = π/4 x d2 x h x w, => W = π/4 x 0.52 x 1.55 x 480 => W = 146.08 kg.
6. Given: cupola diameter = 30cm, mass of bed charge = 270kg, coke density = 545kg/m3. Find height of groove.
a) 6 m
b) 5 m
c) 3 m
d) 7 m
Answer: d
Clarification: Here, d = 30cm = 0.3m, w = 545 kg/m3, W = 270kg. Therefore, according to the formula, W = π/4 x d2 x h x w, => h= 270 / (π/4 x 0.32 x 545) => h = 7.008m.
7. Height of the groove is inversely related to the diameter of the cupola.
a) True
b) False
Answer: a
Clarification: According to the formula, W = π/4 x d2 x h x w, the height of the groove is inversely proportional to the diameter of the cupola, that is, with an increase in the height there is a decrease in the diameter of the cupola.
8. The weight of the bed charge does not depend on which of the following factor?
a) Diameter of cupola
b) Height of groove
c) Type of metal used
d) Coke weight density
Answer: c
Clarification: The weight of the bed charge depends only on the diameter of the cupola, height of the groove and the coke weight density. It does not depend on the type of metal used.
9. Given: cupola diameter = 53cm, mass of bed charge = 465kg, height of groove = 7.2m. Find coke density.
a) 372.72 kg/m3
b) 292.73 kg/m3
c) 223.62 kg/m3
d) 390.57 kg/m3
Answer: b
Clarification: Here, d = 53cm = 0.53m, W = 465kg, height of groove, h = 7.2m. Therefore, according to the formula, W = π/4 x d2 x h x w => w= 465 / (π/4 x 0.532 x 7.2) => w = 292.73 kg/m3.
10. The melting rate is directly proportional to the diameter of the cupola.
a) True
b) False
Answer: b
Clarification: The melting rate is inversely proportional to the square of the diameter of the cupola, that is, with an increase in the diameter there would be a decrease in the melting ratio and vice versa.