Questions and answers for exam Preparation

MCQs

Total Questions : 1628 | Page 15 of 163 pages

Question 141. In a __________ rivetted joint, the number of rivets decreases from the innermost row to the outermost row.

Chain
Diamond
Zig-zag
None of these

Discuss Question

Answer: Option B. -> Diamond

Question 142. Steam economy is defined as the amount of evaporation per unit amount of steam used, while the capacity is the total evaporation obtained per hour. Use of multiple effect in evaporation

Increases capacity
Increases economy
Does not affect the capacity
Both B & C

Discuss Question

Answer: Option D. -> Both B & C

Question 143. The practical representative values of HETP for a number of commercial operations lies within a range of __________ metre.

0.1-0.2
0.2-0.5
0.4-0.9
1.2-1.5

Discuss Question

Answer: Option C. -> 0.4-0.9

Question 144. Pick out the wrong statement.

Lug supports are less expensive than other type of supports
A pipe is differentiated from a tube by the fact that a pipe has a greater wall thickness compared to the tube
A reducer is used to change the direction of a pipe in a straight run
The method of fixing tubes to a tube sheet by expanding is called 'tube rolling'

Discuss Question

Answer: Option C. -> A reducer is used to change the direction of a pipe in a straight run

Question 145. Pick out the wrong statement pertaining to the design of a basket type evaporator.

It is used for high viscosity liquor having large rate of scaling
The tube bundle is suspended on bracket
There is no central downtake
Downtake is formed by the annular space between the bundle and the shell

Discuss Question

Answer: Option A. -> It is used for high viscosity liquor having large rate of scaling

Question 146. The operating velocity in the absorption tower is usually 40-50% of the flooding velocity. Packed absorption towers are normally designed for a pressure drop of about __________ mm of water column per metre height of packing.

1-5
20-40
100-150
1000-1500

Discuss Question

Answer: Option B. -> 20-40

Question 147. In packed absorption tower, onset of flooding usually occurs at a pressure drop of about __________ mm of water column per metre height of packing.

25-50
50-75
200-250
750-1000

Discuss Question

Answer: Option B. -> 50-75

Question 148. In perforated plate towers, the

Hole sizes may be around 1/8" or 3/16"
Total hole area may be around 6 to 15% of tower cross-sectional area
Pressure drop is less compared is similar bubble cap towers
All of the above

Discuss Question

Answer: Option D. -> All of the above

Question 149. A forced circulation long tube vertical evaporator as compared to the natural circulation evaporator

Is economical in operation
Employs high velocity, high heat transfer rate and less heating surface requirement
Employs a centrifugal pump placed between external downtake from vapor drum and inlet to tube bundle
Both B & C

Discuss Question

Answer: Option D. -> Both B & C

Question 150. Joint efficiency (J) for a seamless pipe is