101. The difference between Cornish boiler and Lancashire boiler is that
(a) former is fire tube type and latter is water tube type boiler
(b) former is water tube type and latter is fire tube type
(c) former contains one fire tube and latter contains two fire tubes
(e) none/of the above.
Ans: c
102. In accelerated circulation type boiler
(a) heating takes place at bottom and the water supplied at bottom gets converted into the mixture of stdam bub bles and hot water which rise to durm
(b) 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 from of mixture of water and steam
(c) feed pump is employed to supplement natural circulation in water wall type furnace
(d) water is converted into steam in one pass without any recirculation
(e) water is fed under high pressure and high velocity.
Ans: b
103. Pick up the wrong statement about water tube boiler in comparison to fire tube boilers
(a) former generates steam at high pres¬sure
(b) former occupies less space for same power
(c) rate of steam flow is more in former case
(d) former is used for high installed capacity
(e) chances of explosion are less in former case.
Ans: e
104. The number of drums in Benson steam generator is
(a) one
(b) two
(c) one steam drum and one water drum
(d) no drum
(e) none of the above.
Ans: d
105. A fusible plug is fitted in small boilers in order to
(a) avoid excessive build up of pressure
(b) avoid explosion
(c) extinguish fire if water level in the boiler falls below alarming limit
(d) control steam dome
(e) remove molten ASL.
Ans: c
106. The fusible plug in small boilers is located
(a) in the drum
(b) in the fire tubes
(c) above steam dome
(d) over the combustion chamber
(e) at the inlet of chimney.
Ans: d
107. Fusible plug for boilers is made of fusible metal containing tin, lead, and
(a) bismuth
(b) copper
(c) aluminum
(d) nickel
(e) iron.
Ans: a
108. Boiler H.P. is defined as the
(a) steam evaporation rate per kg of fuel fired
(b) work done in evaporating 1 kg of steam per hour from and at 100°C into dry saturated steam
(c) the evaporation of 15.65 kg of water per hour from and at 100°C into dry saturated steam
(d) work done by 1 kg of steam at saturation condition
(e) heat consumed in evaporating 1 kg water at 0°C to steam at 100°C and 1.033 kg/cm pressure.
Ans: c
109. In forced recirculation type boiler,
(a) heating takes place at bottom and the water supplied at bottom gets con-verted into the mixture of steam bubbles and hot water which rise to drum
(b) 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
(c) feed pump is employed to supplement natural circulation in water wall type furnace
(d) water is converted into steam in one pass without any recirculation
(e) heating of water takes place in stages.
Ans: c
110. The ratio of heat utilised to produce steam and the heat liberated in furnace is known as
(a) boiler effectiveness
(b) boiler evaporative capacity
(c) factor of evaporation
(d) equivalent evaporation
(e) boiler efficiency.
Ans: e
111. Steam in water tube boiler as compared to fire tube boiler
(a) can be raised rapidly
(b) is raised at slower rate
(c) is raised at same rate
(d) could be raised at fast/slow rate depending on design
(e) none of the above is true.
Ans: a
112. Thermal efficiency of well maintained boiler will be of the order
(a) 20%
(b) 40%
(c) 50%
(d) 75%
(e) 90%.
Ans: e
113. Thermal efficiency of a thermal power plant is of the order of
(a) 15%
(b) 20%
(c) 30%
(d) 45%
(e ) 60%.
Ans: c
114. It is required to produce large amount of steam at low pressure. Which boiler should be used ?
(a) pulverised fuel fired boiler
(b) cochran boiler
(c) lancashire boiler
(d) babcock and wilcox boiler
(e) stoker fired boiler.
Ans: c
115. The overall efficiency of thermal power plant is
(a) boiler efficiency, turhine efficiecny, generator efficiency
(b) all the three above plus gas cycle ef-ficiency
(c) carnot cycle efficiency
(d) regenerative cycle efficiency
(e) rankine cycle efficiency.
Ans: a
116. Which type of boiler can meet rapid changes of load
(a) vertical fire tube type
(b) horizontal fire tube type
(c) horizontal water tube type
(d) vertical water tube type
(e) forced circulation type.
Ans: e
117. In forced circulation type boiler
(a) 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
(b) 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
(c) feed pump is employed to supplement natural circulation in water wall type furnace
(d) water is converted into steam in one pass without any recirculation
(e) water is heated in a large number of tubes.
Ans: d
118. Boiler stays are used to
(a) prevent flat surfaces under pressure from tearing apart
(b) take care of failure in shear
(c) take care of failure in compression
(d) provide support for boiler
(e) provide foundation of boiler.
Ans: a
119. The radius of a dished head is taken approximately as
(a) one-fourth
(b) half
(c) one
(d) two
(e) three.
Ans: c
120. Size of boiler tubes is specified by
(a) mean diameter and thickness
(b) inside diameter and thickness
(c) outside diameter and thickness
(d) outside diameter and inside diameter
(e) outside diameter alone.
Ans: c
121. The heat loss in a boiler takes place in the form of
(a) heat carried away by flue gases
(b) heat carried away by ash
(c) moisture present in fuel and steam formed by combustion of hydrogen in fuel
(d) radiation
(e) all of the above.
Ans: e
122. The major axis of elliptical manholes on the shell should be provided
(a) longitudinally
(b) circumferentially
(c) on dished end
(d) anywhere
(e) vertically.
Ans: b
123. In which of the following boilers, the draught in furnace is increased by utilizing exhaust steam from engine
(a) lancashire boiler
(b) locomotive boiler
(c) babcock and wilcox boiler
(d) cochran boiler
(e) benson boiler.
Ans: b
124. With increase in load, radiant superheater has
(a) drooping characteristic
(b) lihear characterisstic
(c) rising characteristic
(d) flat characteristic
(e) none of the above.
Ans: a
125. With increase in load, convection superheater has
(a) drooping characteristic
(b) linear characterisstic
(c) rising characteristic
(d) flat characteristic
(c) none of the above.
Ans: c