101. In which the following regions of a boiler would you find the highest temperature of flue gas?
(A) Economizer
(B) Air preheater
(C) Boiler Drum
(D) Superheater
102. The ratio of mass rate of water feeding to the steam-generating tubes to the mass flow rate of generated steam is defined as
(A) Steam generation ratio
(B) Circulation ratio
(C) Turndown ratio
(D) Evaporation ratio
103. Which is the common coal firing system used in Indian thermal power plants?
(A) Pulverized coal firing
(B) Stoker firing
(C) Fluidized bed
(D) Pressurized bed
104. Which of the following is not true about Supercritical boilers?
(A) Supercritical Boilers don’t have a steam drum
(B) They operate above steam pressures of 22.064 MPa
(C) There’s an increase in the thermodynamic efficiency of the Rankine cycle
(D) The heat transfer area requirement is lower in comparison to subcritical boilers
105. What should be the silica percentage in superheated steam for the efficient operation of steam turbines?
(A) 0.2 ppm
(B) 0.02 ppm
(C) 2 ppb
(D) 2 ppm
106. High-pressure boilers are always
(A) Bottom supported
(B) Top supported
(C) Can be supported from either
(D) None of the above
107. Silica carryover in steam
(A) Decreases when pH of boiler water is increased or Pressure of boiler is decreased
(B) Decreases when pH of boiler water is decreased or the pressure of the boiler is increased
(C) Is not dependent on pH of boiler water and only dependent on the pressure of the boiler
(D) Is not dependent on pH of boiler water and only dependent on the pressure of the boiler
108. Which of the following is not a property of Boiler Quality plates?
(A) Low carbon
(B) Killed steel
(C) Thin
(D) High tensile strength
109. Which of the following can be used as a tube material (without hampering performance and efficiency) of boiler superheater exposed to a maximum flue gas temperature of 1025 degree Celsius
(A) SA209
(B) SA516
(C) SA213T-11
(D) SA106
110. To drain condensate from the main steam line, the following type of trap is a suitable trap.
(A) Float
(B) Bimetallic
(C) Thermodynamic
(D) None of the above
111. The Circulation ratio for once-through steam boilers is
(A) Greater than 1
(B) Less than one
(C) Unity
(D) Can take any value depending on the type of circulation employed
112. The Atmospheric Fluidised bed Boilers have higher fluidizing velocities in comparison to Pressurised Fluidized Bed Combustion units. For other conditions being constant, the heat transfer coefficient of Atmospheric Fluidised Bed Combustion units is:
(A) Lower
(B) Higher
(C) Equal
(D) Cannot be determined
113. The sulphur retention of Fluidised Bed Combustion boilers is dependent on
(A) The temperature of Bed
(B) Pressure of Bed
(C) The porosity of sorption material employed
(D) All of the above
114. To ensure that the tubes do not buckle or distort laterally, the loose tube waterwalls of a boiler should necessarily be supported from
(A) Top
(B) Bottom
(C) Laterally
(D) Either (B) or (C)
115. It was found that the packing of a steam line operating at a temperature of 600° C and pressure of 200kgf/cm2 needs to be replaced. It is recommended to replace it with the packing made from compressed asbestos fiber jointing sheet packing of type:
(A) Style 51 Super
(B) Universal Metallic
(C) Style 54 Super
(D) Style 51 High Pressure
116. Na2SO3 is not prescribed for High-Pressure boilers operating above 1000 psi due to:
(A) Decomposes to SO2
(B) Decomposes to H2S
(C) Both of the above
(D) Na2SO3 can be used in boilers operating above 1000 psi
117. The severity of condensate induced water hammer does not depend upon :
(A) Amount of condensate subcooling
(B) Amount of non-condensable in the void
(C) Size of the void
(D) Static pressure inside the pipe
118. The pH of feedwater in which Hydrazine dosing is practiced
(A) remains the same after and before dosing
(B) Increases after hydrazine dosing
(C) decreases after hydrazine dosing
(D) Cannot be determined
119. The terminal point of one end of a steam piping is supported rigidly and the other end of steam piping is attached to a stationary equipment. Which of the following supports should be used?
(A) Spring hangers
(B) Stanchion
(C) Rigid strut
(D) Rod hangers
120. Based on flue gas flow the boiler bank types are possible:
(A) Single-pass cross flow
(B) Multipass cross flow
(C) Multipass longitudinal flow
(D) All are possible
121. Phosphate hideout is most evident in boiler tubes with :
(A) low mass flow and highest heat flux
(B) low mass flow and lowest heat flux.
(C) high mass flow and highest heat flux.
(D) high mass flow and lowest heat flux.
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