# Steam Boilers and Engines MCQ Questions & Answers

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

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 2

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

Question 3

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 4

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 5

La-mont boiler, is a high pressure water tube steam boiler working on forced circulation.

A. Agree
B. Disagree

Question 6

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 7

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 8

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 9

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 10

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 11

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 12

The fire tubes in a Cochran boiler are

A. horizontal
B. vertical
C. inclined

Question 13

The temperature of condensate is __________ on leaving the condenser than that of circulating water at inlet.

A. higher
B. lower

Question 14

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 15

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 16

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 17

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 18

A single acting steam engine produces __________ power than that of double acting steam engine.

A. equal
B. half
C. double
D. four times

Question 19

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 20

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 21

The fire tubes in a Scotch marine boiler are

A. horizontal
B. vertical
C. inclined

Question 22

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 23

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 24

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 25

The natural draught is produced by

A. steam jet
B. centrifugal fan
C. chimney
D. both (a) and (b)

Question 26

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 27

A safety valve mainly used with locomotive and marine boilers is

A. lever safety valve
C. high steam and low water safety valve

Question 28

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 29

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 30

A safety valve usually employed with stationary boilers is

A. lever safety valve
C. high steam and low water safety valve
D. all of these

Question 31

The function of a connecting rod is not to convert reciprocating motion of the piston into rotary motion.

A. TRUE
B. FALSE

Question 32

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 33

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 34

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 35

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 36

The average operating pressure of Benson boiler is

A. 100 bar
B. 150 bar
C. 200 bar
D. 250 bar

Question 37

The shell diameter of a Locomotive boiler is

A. 1 m
B. 1.5 m
C. 2 m
D. 2.5 m

Question 38

Loeffler boiler is a water tube boiler using a forced circulation of water.

A. TRUE
B. FALSE

Question 39

An economiser __________ the steam raising capacity of a boiler.

A. increases
B. decreases
C. has no effect on

Question 40

The length of shell of a Locomotive boiler is

A. 1 m
B. 2 m
C. 3 m
D. 4 m

Question 41

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 42

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 43

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 44

Fire tube boilers are

A. internally fired
B. externally fired
C. internally as well as externally fired
D. none of these

Question 45

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 46

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 47

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 48

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 49

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