Pressure Vessels and Engines MCQ with Answers

306) In forced circulation type boiler

heating takes place at bottom and the water supplied at bottom gets converted into the mixture of steam bubbles and hot water which rise to drum

water is supplied in drum and through down-comers located in atmospheric condition it passes to the water wall and rises to drum in the form of mixture of water and steam

feed pump is employed to supplement natural circulation in water wall type furnace

water is converted into steam in one pass without any recirculation

Answer is:

water is converted into steam in one pass without any recirculation

307) Boiler stays are used to

Answer is:

prevent flat surfaces under pressure from tearing apart

308) The radius of a dished head is taken approximately as

Answer is:

one

309) Size of boiler tubes is specified by

Answer is:

outside diameter and thickness

310) The heat loss in a boiler takes place in the form of

Answer is:

all of the above.

Explanation:

The heat loss in a boiler takes place in the form of
* heat carried away by flue gases
* heat carried away by ash
* moisture present in fuel and steam formed by combustion of hydrogen in fuel