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EXAMINATION BOARD OF BOILERS

(MAHARASHTRA STATE)
(Under The Boiler Operation Engineer's Rule, 2011)
Boiler Technology -I
7th February 2015
[TIME:

10-00 A.M. to 1-00 P.M.]

(MAx. MARKS
: 100)

Notes.-(l)
(2)
(3)
(4)
(5)

The question paper is divided into two sections.

Section-l is compulsory.
Answer any four questions from Section-2.
Answer should be brief and to the point.
All Answers of one question should be at one place only.
SECTION-l
Answers all questions
Marks

1.

(a)

Choose right answer :(i)

(ii)

(iii)

10

Boiling temperature of water depends on(a)

Quality of fuel

(b)

Quantity of heat added

(c)

Vessel pressure in which water is heated

(d)

All of the above.

Safety valve is a . . ..
(a)

Accessories

(b)

Mounting

(c)

Decorative

(d)

None of the above.

....

in the boiler

Pressure drop across which type valve is more(a)

Gate valve

(b)

Globe valve

(c)

Butterfly valve

Cd) Safety valve.

(iv)

Calorific value of fuel oil is higher as compared to other fuel

because of
.
(a)

Presence of oxygen in it

(b)

Presence of sulpher in it

(c)

Presence of volatile organic compounds in it

Cd) Presence of hydrogen in it.

[Turn over

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Marks
(v)

Function of Deaerator is to
(a)

Remove dissolved gaseous from the feed water

(b)

Remove only oxygen from the feed water

(c)

Remove silica from the feed water

(d)
(vi)

(vii)

None of the above.

Hot air from Air heater

(a)

improves combustion

(b)

Increases thermal efficiency of the boiler

(c)

stabilises fuel combustion

(d)

All of the above.

Blowdown is required to

(a)

Controldrum pressure

(b)

Control Boiler water PH

(c)

Control Alkanity of Boiler water

(d)

Control Total Dissolved Solids (TDS) of Boiler water.

Scaling in Boiler tube is not desired as it

(viii)

(ix)

(x)

(b)

(a)

Overheats the tube material and leads to failure

(b)

Cause obstruction of water circulation causing overheating

of tube.

(c)

Reduces heat transfer and hence, efficiency of the boiler

(d)

All of the above.

Orsat apparatus is used for

(a)

Fuel analysis

(b)

Water analysis

(c)

Air analysis

(d)

Flue gas analysis.

Attemperation is done to

(a)

Control of steam pressure

(b)

Control of steam temperature

(c)

Control of feed water silica

(d)

None of the above.

Explain the following in one or two sentence:(i)

(ii)

Dryness fraction of dry saturated steam

Mobrey switch

(iii)

ARC of boiler feed pump

(iv)

HGI of coal

(v)

3 Ts.

10

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, 3
Marks
SECTION-2

Answer any four questions, Answer should be short and to the point only:2.

Briefly explain about Boiler Mountings and Boiler Accessories.

(b)

How air preheater improves boiler performance? Describe the working of tubular airheater.

(c)

Efficiency calculated on LCV basis is higher than efficiency

calculated on GCV basis. Explain this with suitable example,

(d)

A 250 TPH, 110 kg/ern", 500C boiler consumes 1300tons of fuel

per day with GCV of 3800 kcallkg. Feed water inlet temperature
is 140C and Make-up water is negligible.
(Enthalpy of steam - 803 kcallkg)-

(a)

(i)
(ii)

3.

(a)

(ii)

(i)
(iii)
(iv)

Suspended solids and Total dissolved solids of Water.

Lifting pressure and reset pressure ofspring loaded safety valve.

Give brief description of the following (any two):(ii)

Sugar test of Boiler feed water

Latent heat
Membrane type water wall
Coal mill.

(c)

Explain the function of Steam Drum. Write name of four important

Drum internals.

(d)

Steam is generated in a boiler at 100 kg/ em" (ab) and 480C.

Assume drum pressure is equal to steam pressure. Using steam
table find-

(i)
(ii)
(iii)

4.

Calculate Equivalent evaporation in Tons per hour from and

at 100C.

Describe the difference :(i)

(b)

Calculate efficiency of Boiler by direct method

(a)

Saturated steam temperature

Degree of superheat
Enthalpy of the steam.

Explain the following terms (any two):(i)

(ii)

Biomass fuel
Buckstay

(iii)

Gagging of safety valve

(iv)

Fusible plug.

(b)

What are the various methods used for flow control of a fan? Among
these which are energy efficient methods?

5 .:

(c)

Explain the term supercritical. What are the main differences in

between sub-critical and super-critical Boiler?

(d)

Size of a rectangular water-tank is 5 meter x 8 meter and height is 10

6
meter. Ifwater level is 70%in the tank, then calculate the volume
of water available in the tank in liter.
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Marks
5.

(a)

Explain the function of steam trap. What tests are carried-out to

detect defective traps?

(b)

Explain the various processes in Rankine cycle.

(c) Describe
(i)
(ii)

(iii)
(d)

the difference between ( any two):-

Direct and indirect method of efficiencycalculation

Sub-critical and Super-critical Boiler
Renewable and Non-renewable energy.

Following parameters are noted from ultimate analysis of a coal

sample:(i)

Carbon-53%

(ii)

Sulpher-2%

(iii)

Hydrogen-2%

(iv)

02-1.5%.

Calculate theoretical quantity of air required in kg. for burning 1kg coal.
6.

Answer any four :-

20

(a)

Describe the function of Air nozzles in AFBC and CFBC Boiler.

(b)

Describe about anyone of the following external water treatment

process .....

Softener

DMPlant

RO Plant

(c)

What precautions are to be taken during storage of bagasse?

(d)

Describe the fuel feeding system of a spreader stoker boiler.

(e)

Describe about scoopcontrol of Boiler feed pump in a PF Boiler.

(/) Why spiral wall design is adopted in a Supercritical Boiler? Why Transition header is required in this case?

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EXAMINATION BOARD OF BOILERS

(MAHARASHTRA STATE)
(Under The Boiler Operation Engineer's Rule, 2011)
Boiler Technology - II
7th February 2015
[TIME;

2-30

P.M.

to 5-30

P.M.]

(MAx. MARKs ; 100)

Note .-(1)

The question paper is divided into two sections.

(2) Section-I is compulsory.

(3) Answer any (our questions from Section-2.
(4) Answer should be brief and to the' point.
(5) All Answers of one question should be at one place only.
Marks
SECTION-l
Answer all questions
1. (a) State True or False. ;(i)

(b)

Bomb calorimeter is used to measure calorific value of fuel

(ii)

Hydrazine is used in boiler water for TDS control

(iii)

Steam drum air vent is closed before firing of boiler

(iv)

Set pressure of Superheater safety valve is kept higher than

drum safety valve

(v)

Flow regulation of fan by damper control is an energy efficient

method.
5

Define following terms in one or two sentence:(i)

(ii)

Three element control of drum level

Stoichiometric air fuel ratio

(iii)

Turndown ratio

(iv)

BMCR '- ~~

(v)
(c)

\(1

Flame impingement.

Convert following units as directed:(i)

(ii)

Convert 2300 Kcal into KJ

Convert 1450 psi into kg/em?

(iii)

Convert 1200 mmwc to kg/ern"

(iv)

Convert 1 kwh into kcal

(v)

10

Convert 23 MPa to kg/ern".

[Turn

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y !~Marks

SECTION-2
Answer any four questions. Answer should be short and to the point only.
2.

(a)

Narne four important parameters of boiler water that is measured

regularly to monitor water quality.

(b)

List out various losses in a boiler during operation.

Explain the procedure of annual inspection of boiler for renewal of

certificate as per Indian Boiler Regulation (IBR).

(c)

(d) 1500Tons of coal having 46%Ash is used in a boiler in a particular

day. 20% of the ash generated is drained from boiler as bottom

ash. Rest of the ash is fly ash. Calculate fly ash generation on
that particular day.
3.

(a)

Explain the term furnace purging. Why it is required?

(b)

Write about anyone of the commonlyused ND test method used in

boiler house.

(c)

Write suitable material for following for a 100 TPH, 55 kg/em",

500 c boiler.-

(i)
(ii)

Water wall tube

Steam drum

(iii)

Final super heater tube

(iv)

Main steam pipe line

(d) Specificfuel consumption of a 300 TPH boiler is 0.2 kg of fuel per kg

of steam. Calculate yearly net financial burden to the company if

cost of fuel increased by 50 rupees per ton. Consider average 90%
loading of the boiler and 300 running days in a year.
4.

(a)

Narne any four general practices to be adopted in boiler operation

for efficient use of fuel for steam generation.

(b)

List out some critical parameters to be monitored while boiler is in

operation.

(c)

Explain how scaling takes place in boiler tube and How it affects
Boiler performance?

(d) Exhaust flue gas temperature of a Boiler is 142 C. If ambient

What automatic action is taken because of safety interlocks in the

followingcases in a boiler?

temperature is 28 C then calculate energy loss in flue gas per

kilogramin kcaI/kg.Considerspecificheat offluegas as 0.23kcallkg.

5.

(a)

(i)

Drum level very high

(ii) Furnace pressure very high

(b)

(iii)

Deaerator level very low

(iv)

Superheated steam temperature high

List out some important field instruments used at boiler along with
its purpose.

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1330

(c)

Describe some important reasons of boiler tube failure. What

proactive action can be taken to avoid this?

(d)

Efficiencyof a 300TPH Coal fired boiler is 84%. Calculate quantity

of coal required per day if the boiler runs in full load. Consider
feed water temperature 1400 C and GCVof coal 3600 Kcal/kg a'lld
enthalpy of final superheated steam is 803 kcal/kg.

6. 'Write short notes (any four) :(a)

Off season maintenance of baggase fired boiler.

(b)

Controlling mill temperature ofPF fired boiler.

(c)

Bed slumping of AFBC Boiler.

(d)

Wet mode operation of supercritical boiler.

(e)

Loop seal of CFBC Boiler.

(/) RLA study

(g) Hydro test of boiler pressure parts.

Marks
5
6

20

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EXAMINATION BOARD OF BOILERS

(MAHARASHTRA

STATE)

(Under The Boiler Operation Engineer's Rule, 2011)

Engineering Drawing
8th February 2015
10-00 A.M. to 1-00 P.M.]

[TIME:

(MAx.

MARKs : 100)

Notes.-(1) Answer any five questions.

(2) Marks are indicated at the right hand side of the question
Marks
1.

Draw general arrangement of a water tube boiler and showfollowing:(a)

Water wall

(b)

Bank tube

(c)

Primary superheater

(d)

Final superheater

(e)

Economiser

20

(f) Air preheater.

2. Draw-the futluwing-{any tw&h.,__
~~) Draw general arrangement
important components.

3.

- ~--

20

of a Deaerator

and show all its

(b)

Draw P&I diagram of feed water circuit of a boiler.

(c)

Draw freehand sketch of a gauge glass.

(9) Draw, P-V and T-S diagram of rankine cycle.

10

Match the followingsymbols with their name:-

10

(b)

a)

i)

Leveltransmitter

ii)

Steam trap

iii)

Gate valve

iv)

Pneumatic
operated control
valve

v)

Y -type strainer

~
b)

c)

d)

e)

I
1~1

-(j

...

0
---1>Kl-

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Marks
4.

5.

Draw the following (any two):(a)

Neatly sketch spring loaded safety valve and mark its

important parts.

(b)

Draw general arrangement drawing of a pressure Reducing

and De-superheating Station (PRDS) and show all important
components.

(c)

Neatly sketch burden tube type pressure gauge and mark

important parts.

Neatly draw the following (any two):(a)

6.

20

20

Globe valve

(b)

Single -V and Double -V Butt weld

(c)

Steam system of a PF fired power plant showing superheater,

re-heater, steam turbine, condenser, HP and LP bypass.

Draw Front view and Top view of the object given below :..\

Top view

Front view

20