Steam Boilers and Engines MCQs : This section focuses on the "Steam Boilers and Engines". These Multiple Choice Questions (MCQs) should be practiced to improve the Steam Boilers and Engines skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
A device used to increase the temperature of saturated steam without raising its pressure, is called
A. blow off cock
B. fusible plug
C. superheater
D. stop valve
Question 2
A double acting steam engine with a cylinder diameter of 190 mm and a stroke of 300 mm has a cut-off of 0.35. The expansion ratio for this engine is nearly
A. 1.05
B. 2.86
C. 6.65
D. 10.05
Question 3
A draught produced by a chimney due to the difference of densities between the hot gases inside the chimney and cold atmospheric air outside it, is called natural draught.
A. Yes
B. No
Question 4
A grate, in a boiler, is a place in the combustion chamber upon which fuel (wood or coal) is burnt.
A. TRUE
B. FALSE
Question 5
A safety valve mainly used with locomotive and marine boilers is
A. lever safety valve
B. dead weight safety valve
C. high steam and low water safety valve
D. spring loaded safety valve
Question 6
A safety valve usually employed with stationary boilers is
A. lever safety valve
B. dead weight safety valve
C. high steam and low water safety valve
D. all of these
Question 7
A single acting steam engine produces __________ power than that of double acting steam engine.
A. equal
B. half
C. double
D. four times
Question 8
An air preheater is installed
A. before the economiser
B. before the superheater
C. between the economiser and chimney
D. none of these
Question 9
An economiser __________ the steam raising capacity of a boiler.
A. increases
B. decreases
C. has no effect on
Question 10
Cut-off governing of steam engines is a method of controlling the engine output by varying
A. volume of intake steam
B. pressure of intake steam
C. temperature of intake steam
D. all of these
Question 11
Fire tube boilers are
A. internally fired
B. externally fired
C. internally as well as externally fired
D. none of these
Question 12
In a boiler, feed water supplied per hour is 205 kg while coal fired per hour is 23 kg. The net enthalpy rise per kg of water is 145 kJ. If the calorific valve of the coal is 2050 kJ/kg, then the boiler efficiency will be
A. 56%
B. 63%
C. 74%
D. 78%
Question 13
In a glass tube type water indicator for a boiler, one end of the tube is connected to water space and the other end is connected to
A. water space also
B. chimney
C. steam space
D. superheater
Question 14
In a reciprocating steam engine, the heat energy in the steam is converted into mechanical work by the to and fro motion of the piston.
A. Agree
B. Disagree
Question 15
In a uniflow engine
A. steam enters and exhausts through the same port
B. steam enters at one end and exhausts at the centre
C. steam enters at the centre and exhausts at the other end
D. none of the above
Question 16
In natural circulation steam boilers, the circulation of water is by convection currents which are set up during the heating of water.
A. Correct
B. Incorrect
Question 17
In water tube boilers
A. water passes through the tubes which are surrounded by flames and hot gases
B. the flames and hot gases pass through the tubes which are surrounded by water
C. forced circulation takes place
D. none of these
Question 18
La-mont boiler, is a high pressure water tube steam boiler working on forced circulation.
A. Agree
B. Disagree
Question 19
Loeffler boiler is a water tube boiler using a forced circulation of water.
A. TRUE
B. FALSE
Question 20
The aim of a compound steam engine is
A. to reduce the ratio of expansion in each cylinder
B. to reduce the length of stroke
C. to reduce the temperature range in each cylinder
D. all of the above
Question 21
The average operating pressure of Benson boiler is
A. 100 bar
B. 150 bar
C. 200 bar
D. 250 bar
Question 22
The cylinder dimensions of a compound engine may be designed on the basis of
A. equal power developed in each cylinder for uniform turning moment
B. equal initial piston loads on all pistons for obtaining same size of piston rod, connecting rod etc. for all cylinders
C. equal temperature drop in each cylinder for economy of steam
D. all of the above
Question 23
The diameter of Cornish boiler varies from
A. 0.5 to 1 m
B. 1 to 2 m
C. 1.25 to 2.5 m
D. 2 to 3 m
Question 24
The diameter of flue tube in a Cornish boiler is __________ that of the shell.
A. one-fourth
B. one-third
C. two-fifth
D. three-fifth
Question 25
The draught produced by a steam jet issuing from a nozzle placed in the ashpit under the fire grate of the furnace is called
A. induced steam jet draught
B. chimney draught
C. forced steam jet draught
D. none of these
Question 26
The effect of wire drawing is to decrease the area of indicator diagram and thus work done by the engine is reduced.
A. Agree
B. Disagree
Question 27
The fire tubes in a Cochran boiler are
A. horizontal
B. vertical
C. inclined
Question 28
The fire tubes in a Scotch marine boiler are
A. horizontal
B. vertical
C. inclined
Question 29
The function of a connecting rod is not to convert reciprocating motion of the piston into rotary motion.
A. TRUE
B. FALSE
Question 30
The function of a crosshead is to guide motion of the __________ and to prevent it from bending.
A. piston rod
B. connecting rod
C. eccentric rod
D. valve rod
Question 31
The function of a flywheel is
A. to convert reciprocating motion of the piston into rotary motion.
B. to convert rotary motion of the crankshaft into to and fro motion of the valve rod
C. to prevent fluctuation of speed
D. to keep the engine speed uniform at all load conditions
Question 32
The function of a piston rod is
A. to guide motion of the piston rod and to prevent it from bending
B. to transfer motion from the piston to the cross head
C. to convert heat energy of the steam into mechanical work
D. to exhust steam from the cylinder at proper moment
Question 33
The function of a safety valve is
A. to blow off steam when the pressure of steam inside the boiler exceeds the working pressure
B. to indicate the water level inside the boiler to an observer
C. to measure pressure of steam inside the steam boiler
D. none of the above
Question 34
The length of shell of a Locomotive boiler is
A. 1 m
B. 2 m
C. 3 m
D. 4 m
Question 35
The natural draught is produced by
A. steam jet
B. centrifugal fan
C. chimney
D. both (a) and (b)
Question 36
The object of producing draught in a boiler is
A. to provide an adequate supply of air for the fuel combustion
B. to exhaust the gases of combustion from the combustion chamber
C. to discharge the gases of combustion to the atmosphere through the chimney
D. all of the above
Question 37
The power of a boiler may be defined as
A. the ratio of heat actually used in producing the steam to the heat liberated in the furnace
B. the amount of water evaporated or steam produced in kg per kg of fuel burnt
C. the amount of water evaporated from and at 100° C into dry and saturated steam
D. the evaporation of 15.653 kg of water per hour from and at 100° C
Question 38
The pressure of steam in the engine cylinder at the beginning of the stroke is __________ the boiler pressure.
A. equal to
B. less than
C. higher than
Question 39
The rate of steam produced in Benson boiler is
A. 100 tonnes/h
B. 135 tonnes/h
C. 175 tonnes/h
D. 250 tonnes/h
Question 40
The shell diameter of a Locomotive boiler is
A. 1 m
B. 1.5 m
C. 2 m
D. 2.5 m
Question 41
The temperature of condensate is __________ on leaving the condenser than that of circulating water at inlet.
A. higher
B. lower
Question 42
When the circulation of water, in a boiler, is by a centrifugal pump, then the boiler is known as
A. internally fired boiler
B. externally fired boiler
C. natural circulation boiler
D. forced circulation boiler
Question 43
When the speed of the crankshaft is between 100 r.p.m. and 250 r.p.m., the engine said to be a
A. slow speed engine
B. medium speed steam engine
C. high speed steam engine
D. none of these
Question 44
Which of the following boiler is best suited to meet the fluctuating demand of steam ?
A. Locomotive boiler
B. Lancashire boiler
C. Cornish boiler
D. Babcock and Wilcox boiler
Question 45
Which of the following statement is correct ?
A. A fire tube boiler occupies less space than a water tube boiler, for a given power.
B. Steam at a high pressure and in large quantities can be produced with a simple vertical boiler.
C. A simple vertical boiler has one fire tube.
D. all of the above
Question 46
Which of the following statement is correct ?
A. Lancashire boiler is a fire tube boiler.
B. Fire tube boilers are internally fired.
C. Babcock and Wilcox boiler is a water tube boiler.
D. all of the above
Question 47
Which of the following statement is correct for a compound steam engine ?
A. The cost of the engine, for the same power and economy, is more than that of a simple steam engine.
B. The forces in the working parts are increased as the forces are distributed over more parts.
C. The ratio of expansion is reduced, thus reducing the length of stroke.
D. The temperature range per cylinder is increased, with corresponding increase in condensation.
Question 48
Which of the following statement is wrong ?
A. Locomotive boiler is a water tube boiler.
B. Water tube boilers are internally fired.
C. La-mont boiler is a low pressure water tube boiler.
D. all of the above
Question 49
Which of the following statement is wrong ?
A. The factor of evaporation for all boilers is always greater than unity.
B. The amount of water evaporated in kg per kg of fuel burnt is called equivalent evaporation from and at 100° C.
C. The ratio of heat actually used in producing the steam to the heat liberated in the furnace is called boiler efficiency.
D. none of the above
Question 50
Willian's line for the steam engine is a straight line relationship between the steam consumption per hour and
A. indicated power
B. brake power
C. efficiency
D. pressure of steam