practicum report on steam boiler

i
A Study on Operation and Maintenance of Steam
Boiler at DK knitwear Ltd.

ii
Boiler at DK knitwear Ltd.
By
Mosuud jilani Lipon
ID # 14207082
Program: BSME
Department of Mechanical Engineering
IUBAT - International University of Business Agriculture and Technology
4 Embankment Drive Road, Sector-10, Uttara Model town, Dhaka-1230 Bangladesh
15th
April 2018

iv
In the name of Allah, The Most Beneficent, The
Most Merciful and The Most Gracious

v
A Practicum Report Submitted to the Department of
Mechanical Engineering at IUBAT – International
University of Business Agriculture and Technology in
Partial Fulfillment of the Requirements for the Degree
of Bachelor of Science in Mechanical Engineering

viii
Certificate from Organization

ix
Student Declaration
This is to inform that the Practicum Report on " Operation and Maintenance of Steam
Boiler of DK knitwear Ltd. after completion of 10 weeks work in DK knitwear Ltd.
has only been prepared as a partial fulfillment of the Bachelor of Science in Mechanical
Engineering (BSME) Program. It has not been prepared for any other purpose reward
or presentation.
…………………
Lipon Islam
ID#14207082
Program: BSME

x
Acknowledgement
First of all I would like to thank the Almighty Allah for giving me the chance to
complete my Internship and prepare the internship report.
I would like to thank the respected Vice Chancellor of IUBAT Prof. Dr. Abdur rab
because he gave me the opportunity to study in such a beautiful university to acquire
knowledge on BSME that will be very helpful for my prospective career.
I also bring up the name of Prof. Dr. Engr. A. Z. A. Saifullah, respected Chair and
Prof. Engr. Abdul Wadud Coordinator of the Department of Mechanical Engineering
for their excellent guidance throughout the last four years.
I would like to grateful to Mr. Syed A.K.M. Sayeed – Group Director & In-charge
(DK. Knitwear Ltd) Engr. Nripendro nath Sarkar Biplob – Maintenance Manager of
DK Knitwear Ltd, and Mr. Alom Islam –Boiler operator of DK Knitwear Ltd. My
special thanks to Engr. Mr. Rubel Islam, DK Knitwear Ltd. who helped me a lot to
prepare this report .
Finally I would like to express gratitude to Md. Sharifuzzaman, Senior Lecturer,
Department of Mechanical Engineering, for imperative direction on total internship
program and also for guidance in preparing this report.

xi
Boiler at DK Knitwear Ltd.
…………………….. ………………………..
Lipon Islam Md. Sharifuzzaman
ID#14207082 Senior Lecturer
Department of Mechanical Engineering

xii
Abstract
This report described about steam boiler,classification of boiler ,boiler mounting,
boiler accessories, operation & maintenance of boiler, boiler starting & shut downing
systems, and safety operation of boiler. some common problems that occurred during
boiler operation have been also presented in the report along with solutions . Finally
some recommendations are being suggested.

xiii
List of Abbreviations
AR - Automatic Reset
BHP - Boiler Horsepower
BTU - British Thermal Unit
°C - Degrees Celsius
CFH - Cubic Feet per Hour
Cu Ft - Cubic Feet
CFM - Cubic Feet Per Minute
DC - Direct Current
°F - Degrees Fahrenheit
FM -Factory Mutual
FS - Flame Safeguard
Ft - Feet
FTMP -Fakhruddin Textile Mills Ltd.
GPM - Gallons per Minute
Hd - Head
Ht - Height
HTB - High Turndown Burner
Hz -Hertz
In H2O - Inches of Water
IRI - Industrial Risk Insurance
Ib - Pound
LE - Low Emission
LWCO - Low-Water Cut-Off
MM - Million
MFD - Micro-Farad
MR - Manual Reset
NEC - National Electric Code
No. - Number
pH - Measure of the degree of acid or base of a solution
P/N - Part Number
O & M - Operation and maintenance
PR - Program Relay
Psi - Pounds Per Square Inch
SAE - Society of Automotive Engineers
Scfh - Standard Cubic Feet per Hour
T - Temperature
TC - Temperature Control
TI - Temperature Gauge
UL - Underwriter’s Laboratories
V - Volt
WC - Water Column
WSI - Watts Per Square Inch

xiv
Table of Contents
Preparatory Part Page Number
A. Title Page…………….........................................................................................i
B. Cover Page ……….………................................................................................ii
C. Placement letter …. ……………......................................................................vii
D. Certificate from Organization………………………………………………...viii
E. Student's Declaration …………........................................................................ix
F. Acknowledgement……………..........................................................................x
G. A page for supervisor’s comment………..........................................................xi
H. Abstract ……………………………………………………………………… xii
I. List of Abbreviation.....……………………………………………………….xiii
J. Table of contents …………………………………………………............xiv-xix
K. List of Figures………………………………………………………………...xx
CHAPTER-1...................................................................................................................1
Introduction ....................................................................................................................1
1.1 Origin of the report ..............................................................................................2
1.2 Objectives ............................................................................................................2
1.2.1 Broad Objectives ............................................................................................2
1.2.2 Specific Objectives: .......................................................................................2
1.3 Scope.....................................................................................................................2
1.4 Background...........................................................................................................3
1.5 Methodology........................................................................................................3
1.6 Outline of the report..............................................................................................4
1.7 Limitations............................................................................................................4
CHAPTER-2...................................................................................................................5
Company profile.............................................................................................................5
2.1Company Name: ....................................................................................................6
2.2 Company Location:...............................................................................................6
2.3 Vision statement ...................................................................................................6

xv
2.4 Mission statement .................................................................................................6
2.5 Quality Control Laboratory ..................................................................................6
2.6 Quality assurance Inspection ................................................................................6
2.7 Our infrastructure................................................................................................7
2.8 Factory Address ....................................................................................................7
2.9 Major Products.....................................................................................................8
2.10 Name of the Group of Factories .........................................................................8
2.11 DK Knitwear Ltd ................................................................................................8
2.12 Main Production Items of Dk Knitwear Ltd.......................................................8
2.13 Production Area of Dk knitwear Ltd .................................................................8
2.14 Production Capacity of Dk Knitwear Ltd...........................................................9
2.15 Main Production Items of Dk Knitwear Ltd.......................................................9
2.16 Organogram of Employees:..............................................................................10
CHAPTER-3.................................................................................................................11
3.1 Steam Boiler........................................................................................................12
3.2 History of boiler..................................................................................................12
3.3 Materials of Boiler..............................................................................................13
3.4 Boiler Draught ....................................................................................................14
3.5 Types of draught .................................................................................................14
3.5.1 Natural Draught............................................................................................14
3.5.2 Artificial or Mechanical draught..................................................................15
3.6 Classification of boilers: .....................................................................................15
3.6.1 According to Relative Passage of water and hot gases................................15
3.6.2 According to the Number of Tubes..............................................................15
3.6.3 According to the position of the furnace......................................................16
3.6.4 According to the Axis of the Shell..............................................................16
3.6.5 According to the Methods of Circulation of Water and Steam ..................16
3.6.6 According to the use.....................................................................................17
3.6.7 According to Pressure of steam generated...................................................17
3.7.1 BOILER MOUNTING ....................................................................................18
37.1.1 Water Level Indicator ................................................................................18
3.7.1.2 Pressure gauge...........................................................................................19
3.7.1.3 Safety Valve..............................................................................................19
3.7.1.4 Stop Valve (steam stop valve) ................................................................20
3.7.1.5 Blow Off Cock ..........................................................................................21

xvi
3.7.1.6 Feed Check Valve ....................................................................................21
3.7.1.7 Fusible Plug..............................................................................................22
3.7.2 Boiler accessories ............................................................................................22
3.7.2.1Air preheater...............................................................................................23
3.7.2.2 Super heater...............................................................................................23
3.7.2.3 Economiser................................................................................................24
3.7.2.4 Feed pump.................................................................................................24
3.7.2.5 Injector ......................................................................................................25
3.7.2.6 Pressure reducing valve............................................................................25
3.7.3 Boiler Auxiliary ..............................................................................................26
3.7.3.1 Throttle Lever/Regulator...........................................................................26
3.7.3.2 Steam dome...............................................................................................26
3.7.3.3 Air pump ...................................................................................................26
3.7.3.4 Smoke box.................................................................................................26
3.7.3.5 Valve chest/steam chest ............................................................................26
3.7.3.6 Firebox ......................................................................................................27
3.7.3.7 Boiler tubes ...............................................................................................27
3.7.3.8 Smokestack/Chimney................................................................................27
3.7.3.9 FD fan........................................................................................................27
3.7.3.10 ID fan ......................................................................................................27
3.8 Fire Tube or Shell Boiler ....................................................................................28
3.8.1 Working Principle of a Fire Tube Boiler........................................................29
3.8.2 Operation of Fire Tube Boiler .........................................................................30
3.8.3 Types of Fire Tube Boilers:.............................................................................31
3.8.3.1 Cornish boiler............................................................................................31
3.8.3.2 Lancashire boiler.......................................................................................32
3.8.3.3 Locomotive boile ......................................................................................32
3.8.3.4 Scotch marine boiler .................................................................................33
3.8.3.5 Admiralty-type direct tube boiler..............................................................34
3.8.3.6 Horizontal return tubular boiler ................................................................35
3.8.3.7 Immersion fired boiler...............................................................................36
3.8.3.8 Vertical fire-tube boiler.............................................................................36
3.8.4 Advantages of fire tube boiler .........................................................................37
3.9 Water Tube Boiler ..............................................................................................37
3.9.1 Working Principle of Water tube boiler.......................................................37

xvii
3.9.2 Operation of water tube boiler .....................................................................39
3.9.3 Types of Water Tube Boiler:........................................................................40
3.9.4 Advantage of Water tube boiler:..................................................................40
CHAPTER-4.................................................................................................................41
Operation of Steam Boiler............................................................................................41
4.1 Operation.............................................................................................................42
4.2 Boiler startup & shutdown procedure.................................................................42
4.2.1 Boiler startup...................................................................................................42
4.2.1.1 Vacuum pulling.........................................................................................43
4.2.1.2 Electrical connection................................................................................44
4.2.1.3 Connecting the oil supply..........................................................................45
4.2.1.4 Water connection ......................................................................................45
4.2.1.5 Water treatment.........................................................................................46
4.2.1.6 Testing of steam pressure switch ..............................................................46
4.2.1.7 Testing of flame detector ..........................................................................47
4.2.1.8 Steam pressure testing of safety valve ......................................................47
4.2.1.9 Switching on Boiler...................................................................................47
4.2.1.11 Observations for satisfactory performance of the boiler.........................49
4.2.2 Boiler shut down ..........................................................................................50
4.3 Boiler Safety Operation ......................................................................................51
4.3.1 Boiler Room Doors ......................................................................................51
4.3.2 safety assurance during Operating the Boiler ..............................................52
4.3.3 Fire Safety Plan...........................................................................................53
4.3.4 Sources of Fire kept way from the Boiler Room .........................................53
4.3.5 Boiler water level .........................................................................................54
4.3.6 Low-water and feedwater controls...............................................................54
4.3.7 Low-water cut off evaporation.....................................................................54
4.3.8 Low-water cutoff slow drain........................................................................54
4.3.9 Firing............................................................................................................55
4.3.10 Water gauges.............................................................................................55
4.3.11 Safety valves ..............................................................................................55
4.3.12 Blow-down valves.....................................................................................55
4.3.13 Starting fires in a boiler..............................................................................56
4.3.14 Hot-water systems......................................................................................56
4.3.15 Firing cycle, power burners.......................................................................56

xviii
4.3.16 Feed Water Pumps .....................................................................................56
4.3.17 Overpressure ..............................................................................................57
4.3.18 Boiler Storage.............................................................................................57
4.3.19 Centrifugal Pumps......................................................................................58
4.4 Causes of Boiler Failures....................................................................................59
CHAPTER-5.................................................................................................................60
Maintenance..................................................................................................................60
5.1 Definition............................................................................................................61
5.1.2 Different Type of Maintenances......................................................................61
5.1.2.1 Preventive Maintenance............................................................................62
5.1.2.2 Corrective Maintenance ............................................................................62
5.1.2.3 Predictive Maintenance.............................................................................62
5.1.2.4 Emergency maintenance ...........................................................................62
5.1.3 Boilers maintenance........................................................................................63
5.1.3.1 Daily Maintenance ....................................................................................63
5.1.3.2 Weekly Maintenance.................................................................................63
5.1.3.3 Monthly Maintenance ...............................................................................64
5.1.3.4 Quarterly Maintenance..............................................................................64
5.1.3.5 Half Yearly Maintenance ..........................................................................64
5.1.3.6 Yearly Maintenance ..................................................................................65
5.1.4 Cleaning .......................................................................................................65
5.1.5 Steam and Condensate Pipe work System Pre-testing Inspection...............66
5.1.6 External Inspections.........................................................................................66
5.1.6.1 Leaks .........................................................................................................67
5.1.6.2 Indicating Devices.....................................................................................67
5.1.6.3 Control Systems ........................................................................................67
5.1.6.4 Valves........................................................................................................67
5.1.6.5 Housekeeping............................................................................................68
5.1.6.6 Signs..........................................................................................................68
5.1.6.7 Piping Supports .........................................................................................68
5.1.7 Internal Inspections..........................................................................................68
5.1.8 Boiler Tests......................................................................................................69
5.1.8.1 Safety/Relief Valve Operational Testing ..................................................69
5.1.8.2 Burner Checking .......................................................................................70
5.1.8.3 Condensate Pump Checking ....................................................................70

xix
5.1.8.4 Water Chemistry Checking.......................................................................70
5.1.8.5 LWFCO Slow Drain Testing ...................................................................70
5.1.8.6 Low Water Fuel Cutoff (LWFCO) Rapid Drain Testing..........................70
5.1.8.7 Pump testing..............................................................................................71
5.1.8.9 Drain Water Gage Glass Danger testing...................................................72
5.1.8.10 Checking System for Leaks ....................................................................72
5.1.9 Pressure and temperature regulators testing.................................................73
5.1.10 Functional Performance Test .....................................................................73
5.2 Problems Finding And Solution..........................................................................75
5.2.1 Problem :No heat or hot water .....................................................................75
5.2.2 Problem :Leaking and dripping....................................................................75
5.2.3 Problem :Strange banging, whistling or gurgling noises .............................75
5.2.4 Problem :Pilot light goes out........................................................................75
5.2.5 Problem :Losing pressure.............................................................................76
5.2.6 Problem :Kettling.........................................................................................76
5.2.7 Problem :Radiators not getting hot ..............................................................76
5.2.8 Problem :Boiler keeps switching itself off...................................................76
5.2.9 Problem :Sensor does not work ...................................................................76
5.2.10 Problem: Boiler fails to ignite....................................................................77
5.2.11 problem: Boiler doesn’t switch on.............................................................77
5.2.12 problem: Very loud explosive noise on ignition........................................77
CHAPTER-6.................................................................................................................78
Conclusion....................................................................................................................78
6.1 Conclusion: .........................................................................................................79
6.2 Recommendation: ...............................................................................................79
6.3 References:..........................................................................................................80

xx
Table of figures
Figures pages
Figure 3.1 : Steam boiler ..........................................................................................12
Figure 3.2 : Water Level Indicator ..........................................................................18
Figure 3.3 : Pressure gauge ......................................................................................19
Figure 3.4 : Safety valve..........................................................................................19
Figure 3.5 : Steam stop valve ..................................................................................20
Figure 3.6 : Blow off cock.......................................................................................21
Figure 3.7 : Feed check valve...................................................................................21
Figure 3.8 : Fusible plug...........................................................................................22
Figure 3.9 : Air preheater .........................................................................................23
Figure 3.10 : Super heater..........................................................................................23
Figure 3.11 : Economiser .........................................................................................24
Figure 3.12 : Feed pump............................................................................................24
Figure 3.13 : Injector .................................................................................................25
Figure 3.14 : Pressure reducing valve .......................................................................25
Figure 3.15 : Fire tube boiler.....................................................................................28
Figure 3.16 : fire tube boiler......................................................................................29
Figure 3.17 : Schematic diagram of fire tube boiler...................................................30
Figure 3.18 : Cornish Boiler......................................................................................31
Figure 3.19 : Lancashire Boiler.................................................................................32
Figure 3.20 : Locomotive Boiler ...............................................................................33
Figure 3.21 : Scotch marine boiler ............................................................................34
Figure 3.22 : Admiralty-type direct tube boiler........................................................34
Figure 3.23 : Horizontal return tubular boiler ..........................................................35
Figure 3.24 : Immersion boiler..................................................................................36
Figure 3.25 : Locomotive Boiler ...............................................................................36
Figure 3.26 : Water tube boiler..................................................................................37
Figure 3.27 : Natural water circulation in a water-tube boiler ..................................38
Figure 3.28 : Longitudinal drum boile ......................................................................39
Figure 4.1 : Connect the Power of all accessories...................................................44
Figure 4.2 : Open the Gas line main valve ..............................................................45
Figure 4.3 : Switch on Boiler Mountain components .............................................48
Figure 4.4 : Check the Water Level gauge..............................................................49
Figure 4.5 : Head phone type Ear plug....................................................................52
Figure 4.6 : Safety Fire Alarm of Boiler room........................................................53
Figure 4.7 : Fire extinguisher bottle (CO2).............................................................53
Figure 5.1 : Types of Maintenances ........................................................................61
Figure 5.2 : Flow chart o f the Boiler Maintenance ...............................................62
Figure 5.3 : Pipe work of steam line of Boiler ........................................................66
Figure 5.4 : Safety/Relief Valve Operational Testing.............................................69
Figure 5.5 : Pump testing.........................................................................................71
Figure 5.6 : Safety Valve Setpoint Testing .............................................................71
Figure 5.7 : Drain Water Gage Glass Danger testing..............................................72
Figure 5.8 : Temperature Gauge...............................................................................73

2
1.1 Origin of the report
This report has been prepared as an integral part of the internship program for the
Bachelor of Mechanical Engineering Program at the Department of Mechanical
Engineering (BSME), International University of Business Agriculture and
Technology. The DK Knitwear Ltd. was nominated as the organization for the
practicum while honorable Course Coordinator of Mechanical Engineering
Department, rendered his kind consent to academically supervise the internship
program.
1.2 Objectives
1.2.1 Broad Objectives: The main objective of this internship is to gather practical
knowledge, experience and understand the pros and cons of the steam boiler
and understanding the basic operation and maintenance of steam fire tube
boiler.
1.2.2 Specific Objectives::
 To Study on components of fire tube Steam Boiler.
 To know operation process of fire tube Steam Boiler.
 To know about maintenance of fire tube Steam Boiler.
 To gather knowledge about boiler controlling system.
 To know about troubleshooting of fire tube boiler.
1.3 Scope
This report will cover the practical knowledge of all components of Steam boiler, O &
M Activities, Quality Management system, study on boiler efficiency and a broad
knowledge of different kinds of Mechanical maintenance through steam generation
sector. Managing the O & M activities of Utility specially steam boiler to maintain it’s

3
require standard and user perception toward it is the main scope of discussion in this
report. All the improved Process that can be used in Steam production for proper
tracking improvement and decreasing extra cost require for operation of technical
activities will also discuss here.
1.4 Background
DK Knitwear Ltd. is a concern of DK Group. It has started the journey at
2004. DK Knitwear Ltd. is a 100% export oriented knit fabric & garments
manufacturing & export industries in Bangladesh. . Then gradually it has increased its
branches as Dryer, Ironing, and Finishing etc. As it is a project of a Group of Industries,
thus quickly it becomes familiar through the country.
DK Knitwear Ltd. has following machineries:
 Steam Boiler : 12 Ton
 Gas Generator : 1000 KW
 Air Compressor : 8 Ton
 W.T.P. : 100 m3
 E.T.P. : 300 m3
1.5 Methodology
A qualitative research method has been used to carry out this study of practicum in DK
knitwear Ltd. There the operating system has used very modern technology. The fuel
connection, the water connection & steam over load safety sector they have automotive
control valve. The specialization of DK Knitwear Ltd is that, they are using Condense
recovery system, thus it saves fuel cost & also prevent air pollution. For this, DK
Knitwear Ltd is using a Condense recovery Boiler of 1 Ton capacity placed on the roof
of Utility building. The steam produced by the Waste Heat recovery Boiler goes to the
main steam header. The information of this report has been collected from the following
sources:

4
1. Machine catalog
2. Plant Management Manual
1. Plant Operation Manual
2. Plant Maintenance Manual
3. Check sheet of Machines.
4. Specialist observation of Boiler supplier.
1.6 Outline of the report
This report consists of six chapters. The First chapter presents Introductory part. The
second chapter discusses about the Company Overview. Third chapter consists of about
Boiler, fourth is about Operation of Steam Boiler . The fifth chapter describes about
Maintenance, Problem finding and Solution. Chapter six consists of Conclusion and
Recommendation.
1.7 Limitations
This report has been prepared for the operation & maintenance of Steam Boiler. But, in
case of diesel/other fuels the operating system will be different. As like the Gas is
supplied to the burner by Gas regulator & the automotive control valve. Also the steam
productivity by burning gas & by burning other fuels will be different. And, gas
consumption can be easily measured by the pressure gauge of gas regulator. But, in case
of other fuels it will be difficult & different way. Thus the study was mainly followed
the gas fuel steam production.

6
2.1Company Name:
DK Knitwear Ltd (DK Group of Industries)
2.2 Company Location:
It’s situated Dhaka - Ashulia Hwy, Jamgora
Saver,Dhaka-1349
(Opposite To Fantasy kingdom )
2.3 Vision statement
To be the most preferred garment, home textile, bags and other sourcing agency for
global clients and to provide automated warehousing and re-distribution solutions to
global clients.
2.4 Mission statement
To conduct the business of DK Group so as to maintain our reputation for credibility
and integrity with our clients, vendors, and employees.To provide customized sourcing
and logistic solutions to global clients having unique requirements. To achieve
consistent high quality levels and on-time delivery schedules, through a team of
committed personnel and a proven set of vendors with World Class, systematic
manufacturing facilities. To open window for new avenue of business diversity. Our
business research and development team always keen to deal new type of product apart
from garments and textile items.
2.5 Quality Control Laboratory
Our products undergo quality control tests at our ultra-modern quality control
laboratory to ensure that the garments meet stringent specifications.
2.6 Quality assurance Inspection
Our goal is to provide our clients with a high quality product that meets or exceeds their
quality expectation. DK Group maintains quality assurance staff to assist in the selection
and development of manufacturers who manufacture products according to DK Group’s
standards and who meet DK Group’s policy, principles, and guidelines. This field

7
function is also responsible for assisting in starting up new production, monitoring
production as it is being made, and communicating with the buyers and production
representatives their findings.
2.7 Our infrastructure
 Group of adroit dedicated professional designers and merchandiser.
 A fully integrated production and finishing unit.
 A professional business development team for the international markets.
 A well mannered work force of people to assist the company in each department
• “from sampling to packing until shipping ".
 We also have a strong design and product development team, which constantly
innovate new products every year, exclusively for our customers who those are
interested.
If you have any new developments, please send us indications. Then we will develop
accordingly as we are having our personal production unit, Manufacturing Unit,
Designing Section, and Showroom here in Dhaka. Your own designs, labels,
trademarks, and other specifications are cordially welcome.
2.8 Factory Address
Zamgara, Savar, Dhaka, Bangladesh
Email: dkkl@dkgbd.com
Web: www.dkgbd.com
HEAD OFFICE
Address:
House# 15, Road# 68/A, Gulshan 1,
Dhaka-1111, Bangladesh.
Tel: 8801-8814070, 9898107
Email: info@dkgbd.com
Web: www.dkgbd.com

8
2.9 Major Products
 All types of bottoms and tops (hi-fashion with critical washes)
 Overall & denim jacket for men's/ ladies/ boy's & girl's
 Polo shirt
 Fancy tee
 Over dyeing of garments
 Basic tee shirt and Dress pant
2.10 Name of the Group of Factories
 DK Knitwear Ltd
 DK Sweater Limited
 DK Textile Limited
 DK Printing Limited
2.11 DK Knitwear Ltd
DK. Knitwear Ltd. is a 100% export oriented knit fabric & garments manufacturing &
export industries in Bangladesh. It started to walk since 2004. It's a well-trained and
experienced member of staff. Our commitment are top quality, best price negotiate, on
time delivery. Always we care for best quality.
2.12 Main Production Items of Dk Knitwear Ltd
We produce all kinds of men, ladies, and children's polo, basic t-shirt, fancy t-shirts
along with embroidery, print, sequence etc.We also do all kinds of pigment wash,
stone wash, garment wash t-shirt.Finally we produce T-shirt, feeder stripe and Eng
stripe t-shir
2.13 Production Area of Dk knitwear Ltd
Textile division
Knitting: 15,000 Sft
Dyeing: 40,000 Sft
Total: 55,000 Sft
Garments division

9
Cutting: 20,000 Sft
Sewing: 60,000 Sft
Finishing: 20,000 Sft
Sample room: 2,000 Sft
Office: 5,000 Sft
Store: 6,500 Sft
Total: 1, 13,500 Sft
Bonded warehouse– 40,000 Sft
Grand Total: 2, 08,500 Sf
2.14 Production Capacity of Dk Knitwear Ltd
Name of Products Pcs. / Day
Basic Tee shirt 40000 pcs
Fancy Tee 10000 pcs
Polo Shirt 10000 pcs
2.15 Main Production Items of Dk Knitwear Ltd
We produce all kinds of All kind of Men's, Ladies, Boys, Girls Sweater, Pullover,
Cardigan & Vest in-
01. 100% acrylic solid, mélange, mixed & twisted form.
02. 100% Acrylic smiling Dull and shiny.
03. 85% 15%, 70/30% , 50/50% acrylic/ wool
04. 100%, 50% 50% Acrylic/ cotton
05. 100% Acrylic and cotton chenille
06. Viscose nylon and cotton/ viscose/ nylon

10
2.16 Organogram of Employees:
Managing
Director
General
Manager
Assistant
General
Manager
Admin Quality Production Utility Store Security
Admin
Officer
Quality
Manager
Production
Manager
Utility
Manager
Store
Manager
Security
Officer
Sr.
Officer
In charge Assistant
manager
Assistant
manager
Supervisor Security
Gird
Jr.
Officer
Supervisor Supervisor Assistant
Engr.
Peon Sub-
Assistant
Engr.
Technical
Manager
Foremen
Technician

12
3.1 Steam Boiler
Figure 3.1 : Steam boiler
A boiler is defined as "a closed vessel in which water or other liquid is heated, steam or
vapor is generated, steam is superheated, or any combination thereof, under pressure or
vacuum, for use external to itself, by the direct application of energy from the
combustion of fuels, from electricity or nuclear energy." Many components make up or
act as a support system for the boiler to meet its designed steam or heat requirements.
There are the tubes that carry the water and/or steam throughout the system; soot
blowers that keep the unit free of fly ash or dust by blowing steam water or air into the
boiler; burners that burn the fuel (oil, gas, coal, refuse); economizers that recover heat
from the exit gas and pre-heat the water used for making steam; and many more such
systems, including brick, refractory, insulation, and lagging, which help the steam-
generating boiler be energy and thermally efficient.
3.2 History of boiler
It may be debated who developed the first steam-generating boiler; however, most will
agree that George Babcock and Steven Wilcox were two of the founding fathers of the
steam-generating boiler. They were the first to patent their boiler design, which used
tubes inside a firebrick-walled structure to generate steam, in 1867, and they formed

13
Babcock & Wilcox Company in New York City in 1891. Their first boilers were quite
small, used lump coal, fired by hand, and operated at a very low rate of heat input. The
solid firebrick walls that formed the enclosure for the unit were necessary because they
helped the combustion process by reradiating heat back into the furnace area. The
Stirling Boiler Company, owned by O.C. Barber and named for the street (Stirling
Avenue) the facility was on in Barberton, Ohio, also began making boilers in 1891.
Their eighth Stirling boiler design was called the H-type boiler (“h” being the eighth
letter in the alphabet) and had a brick setting design. The Stirling boiler was much larger
than the Babcock & Wilcox boiler and used three drums to help circulate the water and
steam flow throughout the boiler.In 1907, the Stirling Boiler Company merged with the
Babcock & Wilcox Company. They renamed their boiler the H-type Stirling, and it
became one of best-selling boilers of its time, probably because of its ability to produce
up to 50,000 pounds of steam per hour.
3.3 Materials of Boiler
The pressure vessel of a boiler is usually made of steel (or alloy steel), or historically
of wrought iron. Stainless steel, especially of the austenitic types, is not used in wetted
parts of boilers due to corrosion and stress corrosion cracking. However, ferritic
stainless steel is often used in superheater sections that will not be exposed to boiling
water, and electrically heated stainless steel shell boilers are allowed under the
European "Pressure Equipment Directive" for production of steam for sterilizers and
disinfectors. In live steam models, copper or brass is often used because it is more
easily fabricated in smaller size boilers. Historically, copper was often used
for fireboxes (particularly for steam locomotives), because of its better formability and
higher thermal conductivity; however, in more recent times, the high price of copper
often makes this an uneconomic choice and cheaper substitutes (such as steel) are used
instead.
For much of the Victorian "age of steam", the only material used for boilermaking was
the highest grade of wrought iron, with assembly by rivetting. This iron was often
obtained from specialist ironworks, such as at Cleator Moor (UK), noted for the high
quality of their rolled plate and its suitability for high-reliability use in critical

14
applications, such as high-pressure boilers. In the 20th century, design practice instead
moved towards the use of steel, which is stronger and cheaper,
with welded construction, which is quicker and requires less labour. Wrought iron
boilers corrode far slower than their modern-day steel counterparts, and are less
susceptible to localized pitting and stress-corrosion. This makes the longevity of older
wrought-iron boilers far superior to those of welded steel boilers.Cast iron may be used
for the heating vessel of domestic water heaters. Although such heaters are usually
termed "boilers" in some countries, their purpose is usually to produce hot water, not
steam, and so they run at low pressure and try to avoid boiling. The brittleness of cast
iron makes it impractical for high-pressure steam boilers.
3.4 Boiler Draught
The difference between atmospheric pressure and the pressure existing in the furnace
or flue gas passage of a boiler is termed as draft. Draft can also be referred to the
difference in pressure in the combustion chamber area which results in the motion of
the flue gases and the air flow.The main objectives of producing draft in a boiler are-
TO provide an adequate supplier of air for the fuel combustion .
TO exhaust the gases of combustion from the combustion chamber .
To discharge this gases to atmosphere through the chimney.
3.5 Types of draught
Draught are mainly two types
i. Natural Draught
ii. Artificial or Mechanical Draught
3.5.1 Natural Draught
The natural draught is obtained with the use of tall chimney which may be sufficient or
insufficient to overcome the losses in the system. Its usefulness depends upon the

15
capacity of the plant and duct work. This system of producing the draught is useful for
small capacity boilers and it does not play much important role in the present high
capacity thermal power plants. A chimney is a vertical structure of masonry; brick, steel
or reinforced concrete built for the purpose of enclosing a column of hot gases to
produce the draught and discharge the gases high enough which will prevent an air
pollution the draught produced by the chimney is due to the temperature difference of
hot gases in the chimney and cold air outside the chimney.
3.5.2 Artificial or Mechanical draught
The draught required in actual power plant is sufficiently high (300 mm of water) and
to meet high draught requirements, some other system must be used which are known
as artificial draught.
3.6 Classification of boilers:
There are a large number of boiler designs, but boilers can be classified according to
the following criteria
3.6.1 According to Relative Passage of water and hot gases
According to Relative Passage of water and hot gases the boilers can be classified as
fire tube boiler and water tube boiler.
(i). Fire Tube Boiler: The hot combustion gases pass through the boiler tubes,
which are surrounded by water, e.g., Lancashire, Cochran, locomotive boilers,
etc.
(ii). Water Tube Boiler: A boiler in which the water flows through some small tubes
which are surrounded by hot combustion gases, e.g., Babcock and Wilcox,
Stirling, Benson boilers, etc.
3.6.2 According to the Number of Tubes
According to the no of tubes, the boilers are classified as single tube boiler and
multitubular boilers.

16
(i). Single Tube Boilers: In single tube steam boilers, there is only one fire tube or
water tube. Simple vertical boiler and Cornish boiler are single tube boilers.
(ii). Multitubular Boilers: In multitubular steam boilers, there are two or more fire
tubes or water tubes. Lancashire boiler, Locomotive boiler, Cochran boiler,
Babcock and Wilcox boiler are multitubular boilers.
3.6.3 According to the position of the furnace
According to position of the Furnace the steam boilers are classified as internally fired
boilers and externally fired boilers.
(i). Internally Fired Boilers: The furnace is located inside the shell, e.g., Cochran,
Lancashire boilers, etc.
(ii). Externally Fired Boilers: The furnace is located outside the boiler shell, e.g.,
Babcock and Wilcox, Stirling boilers, etc.
3.6.4 According to the Axis of the Shell
According to the axis of the shell, the boilers are classified as
(i). Vertical Boilers: In vertical steam boilers, the axis of the shell is vertical.
Simple vertical boiler and Cochran boiler are vertical boilers.
(ii). Horizontal Boilers: In horizontal steam boilers, the axis of the shell is
horizontal. Lancashire boiler, Locomotive boiler and Babcock and Wilcox
boiler are horizontal boilers.
3.6.5 According to the Methods of Circulation of Water and Steam
According to the method of circulation of water and steam, the steam boilers are divided
into –
(i). Natural Circulation Boilers: Water circulates in the boiler due to density
difference of hot and water, e.g., Babcock and Wilcox boilers, Lancashire
boilers, Cochran, locomotive boilers, etc.

17
(ii). Forced Circulation Boilers: A water pump forces the water along its path,
therefore, the steam generation rate increases, Eg: Benson, La Mont, Velox
boilers, etc.
3.6.6 According to the use
According to the use, the boilers are classified as –
(i). Stationary Boilers: These boilers are used for power plants or processes steam
in plants.
(ii). Marine Boilers: These are used on ships.
(iii). Portable Boiler: These are small units of mobile and are used for temporary uses
at the sites.
(iv). Locomotive: These are specially designed boilers. They produce steam to drive
railway engines.
3.6.7 According to Pressure of steam generated
(i). Low-pressure boiler: a boiler which produces steam at a pressure of 15-20 bar
is called a low-pressure boiler. This steam is used for process heating.
(ii). Medium-pressure boiler: It has a working pressure of steam from 20 bars to 80
bars and is used for power generation or combined use of power generation and
process heating.
(iii). High-pressure boiler: It produces steam at a pressure of more than 80 bars.
(iv). Sub-critical boiler: If a boiler produces steam at a pressure which is less than
the critical pressure, it is called as a subcritical boiler.
(v). Supercritical boiler: These boilers provide steam at a pressure greater than the
critical pressure. These boilers do not have an evaporator and the water directly
flashes into steam, and thus they are called once through boilers.

18
3.7.1 BOILER MOUNTING
Boiler mountings are the components generally mounted on the surface of the boiler to
have safety during operation. These are the essential parts of the boiler, without which
the boiler operation is not possible. The following are the important mountings of the
boiler:
1. Water level indicator ( Water level gauge)
2. Pressure gauge
3. Safety valves
4. Stop valve
5. Blow off cock (Blow off valve)
6. Feed check valve
7. Fusible Plug
37.1.1 Water Level Indicator
Figure 3.2 : Water Level Indicator
 It is fitted in front of the boiler and generally present
two in number.
 It is used to indicate the water level inside the boiler. It shows the instantaneous
level of water that is present inside the steam boiler
which is necessary for its proper working.

19
3.7.1.2 Pressure gauge
Figure 3.3 : Pressure gauge
 It is also present in front of the boiler.
 It is used to measure the pressure of the steam inside the
boiler.
 The pressure gauges generally used are of Bourden type
3.7.1.3 Safety Valve
Figure 3.4 : Safety valve
 Safety valves are attached to the steam boiler chest.

20
 It is used to prevent explosion due to excessive internal
pressure. When the internal pressure inside the boiler exceeds its working
pressures than the safety valves blow off the steam and maintains the internal
pressure.
 Generally two safety valves are present on a boiler.
3.7.1.4 Stop Valve (steam stop valve)
Figure 3.5 : Steam stop valve
 It is usually fitted on the highest part of the boiler with the help of a flange.
 The main function of the stop valve is
(i). To control the flow of steam from the boiler to the main
steam pipe.
(ii). To completely shut off the steam supply when required.

21
3.7.1.5 Blow Off Cock
Figure 3.6 : Blow off cock
 It is fitted at the bottom of the boiler drum.
 The functions of blow off cock is
(i). To empty the boiler whenever required.
(ii). To discharge the scale, mud and sediments which gets
collected at the bottom of the boiler.
3.7.1.6 Feed Check Valve
Figure 3.7 : Feed check valve
 It is non-return valve and fitted to a screwed spindle to
regulate the lift.

22
 It is fitted to the shell slightly below the normal water
level of the boiler. A boiler must have its spindle lifted before the pump is
started.
 It regulates the supply of water which is pumped into the
boiler by feed pump.
3.7.1.7 Fusible Plug
Figure 3.8 : Fusible plug
 It is fitted to the crown plate of the furnace or firebox.
 Its function is to extinguish fire in the furnace when the
water level in the boiler falls to an unsafe limit. This avoids the explosion that
may takes place because of the overheating of the furnace plate.
3.7.2 Boiler accessories
These are the devices which are use as integral parts of a boiler, and help in running
efficiently. Though there are many types of boiler accessories, yet the following are
important from the subject point of view.

23
3.7.2.1Air preheater
Figure 3.9 : Air preheater
 It is used to recover heat from the exhaust gases.
 It is installed between the economiser and the chimney.
3.7.2.2 Super heater
Figure 3.10 : Super heater
 It is placed in the path of hot flue gases from the furnace.
 A super heater is an important accessory used in the boiler.
Its main function is to increase the temperature of saturated steam without
raising its pressure.

24
3.7.2.3 Economiser
Figure 3.11 : Economiser
 It is used to heat the feed water by the utilization of heat
from the hot fuel gases before it leaves the chimney.
 A economiser improves the economy of the steam boilers
3.7.2.4 Feed pump
Figure 3.12 : Feed pump
 It is used to deliver water to the boiler.
 These pumps are normally high pressure units that take suction from a
condensate return system.
 Feed pump can be of the centrifugal pump type or positive displacement
type.

25
3.7.2.5 Injector
Figure 3.13 : Injector
 Function of the injector is the same as that of feed pump i.e.; to deliver feed
water to boiler under pressure.
3.7.2.6 Pressure reducing valve
Figure 3.14 : Pressure reducing valve
 the function of the pressure reducing valve is to maintain constant pressure on
its delivery side of the valve irrespective of fluctuating demand of steam from
the boiler.

26
3.7.3 Boiler Auxiliary
The devices incorporated in the boiler circuit to boost up the efficiency and
performance of the steam generation plant and assist in the systematic and adequate
operation of the boiler unit for prolonged periods safely.
3.7.3.1 Throttle Lever/Regulator
Controls the opening of the regulator/throttle valve thereby controlling the supply of
steam to the cylinders.
3.7.3.2 Steam dome
Collects the steam at the top of the boiler so that it can be fed to the engine via the
regulator/throttle valve.
3.7.3.3 Air pump
Provides air pressure for operating the brakes (train air brake system). This is sometimes
called a Westinghouse pump or Knorr pump after George Westinghouse and Georg
Knorr.
3.7.3.4 Smoke box
Collects the hot gas that have passed from the firebox and through the boiler tubes. It
may contain a cinder guard to prevent hot cinders being exhausted up the chimney.
Usually has a blower to help draw the fire when the regulator is closed. Steam
exhausting from the cylinders is also directed up to the chimney through the smokebox
to draw the fire while the regulator is open.
3.7.3.5 Valve chest/steam chest
Small chamber (sometimes cylindrical) above or to the side of the main cylinder
containing passageways used by the valves to distribute live steam to the cylinders.

27
3.7.3.6 Firebox
Furnace chamber that is built into the boiler and usually surrounded by water. Almost
anything combustible can be used as fuel but generally coal, coke, wood or oil are burnt.
3.7.3.7 Boiler tubes
Carry hot gasses from the fire box through the boiler, heating the surrounding water.
3.7.3.8 Smokestack/Chimney
Short chimney on top of the smokebox to carry the exhaust (smoke) away from the
engine so that it doesn't obscure the engineers vision. Usually extended down inside the
smokebox - the extension is called a petticoat. Some railways, e.g. the Great Western
Railway, fitted a decorative copper cap to the top of the chimney.
3.7.3.9 FD fan
Forced Draft Fan is a type of a fan supplying pressurized air to a system. In case of a
Steam Boiler Assembly, this fan is of a great importance.
3.7.3.10 ID fan
Induced Draft fan is used to extract the air from boiler post combustion via
(Electrostatic Precipitator if present) to exhaust through the chimney.

28
3.8 Fire Tube or Shell Boiler
Figure 3.15 : Fire tube boiler
This is the most common type of boiler used in small and medium sized industrial
installations. Fire tube boilers are often produced as ‘packaged’ units complete with
pumps and control system, requiring only connection to a suitable water and fuel supply
before commencing operation.In fire tube boilers the flame and heat gases from
combustion are confined within tubes arranged in a bundle within a water drum. Water
circulates on the outside of the tubes. As the water changes to steam it rises to the top
of the boiler drum and exists through a steam header. A fire-tube boiler is sometimes
called a "smoke-tube boiler" or "shell boiler" or sometimes just "fire pipe".
Fire tube boilers are efficient steam generators for low to medium pressure steam
requirements usually below 15 bar, although shell boilers operating up to 30 bar are
known and steaming rates up to 70,000 kg/hr. Operating at higher pressures and
steaming rates requires thicker plates and tube walls making the design less economic.

29
3.8.1 Working Principle of a Fire Tube Boiler
Figure 3.16 : fire tube boiler
 In fire tube boiler, the fuel is burnt inside a furnace.
 The hot gases produced in the furnace then passes through the fire tubes. The
fire tubes are immersed in water inside the main vessels of the boiler.
 The heat energy of the gasses is transferred to the water surrounds them.
 As a result steam is generated in the water and naturally comes up and is stored
upon the water in the same vessel of fire tube boiler.
 The steam is then taken out from the steam outlet for utilizing for required
purpose. The water is fed into the boiler through the feed water inlet.

30
3.8.2 Operation of Fire Tube Boiler
Figure 3.17 : Schematic diagram of fire tube boiler
Operation of fire tube boiler is as simple as its construction. In fire tube boiler, the fuel
is burnt inside a furnace. The hot gases produced in the furnace then passes through the
fire tubes. The fire tubes are immersed in water inside the main vessel of the boiler. As
the hot gases are passed through these tubes, the heat energy of the gasses is transferred
to the water surrounds them. As a result steam is generated in the water and naturally
comes up and is stored upon the water in the same vessel of fire tube boiler. This steam
is then taken out from the steam outlet for utilizing for required purpose. The water is
fed into the boiler through the feed water inlet.
As the steam and water is stored is the same vessel, it is quite difficult to produce very
high pressure steam from. General maximum capacity of this type of boiler is 17.5
kg/cm2 and with a capacity of 9 Metric Ton of steam per hour. In a fire tube boiler, the
main boiler vessel is under pressure, so if this vessel is burst there will be a possibility
of major accident due to this explosion.

31
3.8.3 Types of Fire Tube Boilers:
1. Cornish boiler
2. Lancashire boiler
3. Locomotive boiler
4. Scotch marine boiler
5. Admiralty-type direct tube boiler
6. Horizontal return tubular boiler
7. Immersion fired boiler
8. Vertical fire-tube boiler
3.8.3.1 Cornish boiler
The earliest form of fire-tube boiler was Richard Trevithick's "high-pressure" Cornish
boiler. This is a long horizontal cylinder with a single large flue containing the fire. The
fire itself was on an iron grating placed across this
Figure 3.18 : Cornish Boiler
flue, with a shallow ashpan beneath to collect the non-combustible residue.
Although considered as low-pressure (perhaps 25 pounds per square inch (170 kPa))
today, the use of a cylindrical boiler shell permitted a higher pressure than the earlier
"haystack" boilers of Newcomen's day. As the furnace relied on natural draught (air
flow), a tall chimney was required at the far end of the flue to encourage a good
supply of air (oxygen) to the fire.

32
For efficiency, the boiler was commonly encased beneath by a brick-built chamber.
Flue gases were routed through this, outside the iron boiler shell, after passing through
the fire-tube and so to a chimney that was now placed at the front face of the boiler.
3.8.3.2 Lancashire boiler
Figure 3.19 : Lancashire Boiler
The Lancashire boiler is similar to the Cornish, but has two large flues containing the
fires. It was the invention of William Fairbairn in 1844, from a theoretical consideration
of the thermodynamics of more efficient boilers that led him to increase
the furnace grate area relative to the volume of water.Later developments
added Galloway tubes (after their inventor, patented in 1848),]
crosswise water tubes
across the flue, thus increasing the heated surface area. As these are short tubes of large
diameter and the boiler continues to use a relatively low pressure, this is still not
considered to be a water-tube boiler.
3.8.3.3 Locomotive boile
A locomotive boiler has three main components: a double-walled firebox; a horizontal,
cylindrical "boiler barrel" containing a large number of small flue-tubes; and a
smokebox with chimney, for the exhaust gases. The boiler barrel contains larger flue-
tubes to carry the superheater elements, where present. Forced draught is provided in

33
the locomotive boiler by injecting exhausted steam back into the exhaust via a blast pipe
in the smokebox.
Figure 3.20 : Locomotive Boiler
Locomotive-type boilers are also used in traction engines, steam rollers, portable
engines and some other steam road vehicles. The inherent strength of the boiler means
it is used as the basis for the vehicle: all the other components, including the wheels,
are mounted on brackets attached to the boiler. It is rare to find superheaters designed
into this type of boiler, and they are generally much smaller (and simpler) than railway
locomotive types.
3.8.3.4 Scotch marine boiler
The Scotch marine boiler differs dramatically from its predecessors in using a large
number of small-diameter tubes. This gives a far greater heating surface area for the
volume and weight. The furnace remains a single large-diameter tube with the many
small tubes arranged above it. They are connected together through a combustion
chamber – an enclosed volume contained entirely within the boiler shell – so that the
flow of flue gas through the firetubes is from back to front.

34
Figure 3.21 : Scotch marine boiler
An enclosed smokebox covering the front of these tubes leads upwards to the chimney
or funnel. Typical Scotch boilers had a pair of furnaces, larger ones had three. Above
this size, such as for large steam ships, it was more usual to install multiple boilers.
3.8.3.5 Admiralty-type direct tube boiler
Extensively used by Britain, before and in the early days of ironclads, the only protected
place was below the waterline, sometimes under an armoured deck, so to fit below short
decks, the tubes were not led back above the furnace but continued straight from it with
Figure 3.22 : Admiralty-type direct tube boiler

35
keeping the combustion chamber in between the two. Hence the name, and considerably
reduced diameter, compared to the ubiquituous Scotch or return tube boiler. It was not
a great success and its use was being abandoned after the introduction of stronger side
armouring – “the furnace crowns, being very near the water-level, are much more liable
to over-heating. Further, on account of the length of the boiler, for an equal angle of
inclination, the effect on the water-level is much greater. Finally, the unequal expansion
of the various parts of the boiler is more pronounced, especially at the top and bottom,
due to the increased ratio between the length and the diameter of the boiler; the local
strains are also more severe on account of the comparatively feeble circulation in long
and low boilers.” All these also resulted in a shorter life. Also, the same length of a
combustion chamber was much less effective on a direct tube than on a return tube
boiler, at least without baffling.
3.8.3.6 Horizontal return tubular boiler
Figure 3.23 : Horizontal return tubular boiler
Horizontal return tubular boiler (HRT) has a horizontal cylindrical shell, containing
several horizontal flue tubes, with the fire located directly below the boiler's shell,
usually within a brickwork setting.

36
3.8.3.7 Immersion fired boiler
Figure 3.24 : Immersion boiler
The immersion fired boiler is a single-pass fire-tube boiler that was developed by Sellers
Engineering in the 1940s. It has only firetubes, functioning as a furnace and combustion
chamber also, with multiple burner nozzles injecting premixed air and natural gas under
pressure. It claims reduced thermal stresses, and lacks refractory brickwork completely
due to its construction.
3.8.3.8 Vertical fire-tube boiler
Figure 3.25 : Locomotive Boiler
A vertical boiler is a type of fire-tube or water-tube boiler where the boiler barrel is
oriented vertically instead of the more common horizontal orientation. Vertical boilers
were used for a variety of steam-powered vehicles and other mobile machines, including
early steam locomotives.

37
3.8.4 Advantages of fire tube boiler
 The water is supplied in shell and outside tubes while hot gas is supplied inside
tubes so the water volume can not be shaken easily when the fire tube boiler is
running.
 It is so easy to use, operate, clean and maintain
 It can be used in small scale industries.
 It is relatively cheaper than water tube boiler.
3.9 Water Tube Boiler
Figure 3.26 : Water tube boiler
A water tube boiler is such kind of a boiler, where the water is heated inside the tubes
and the hot gases surrounded them. It is the opposite of Fire tube boiler, where hot
gasses are passed through the tubes which are surrounded by water.
3.9.1 Working Principle of Water tube boiler
The working principle of water tube boiler is very simple. It consists of mainly two
drums, one is upper drum called steam drum and other is lower drum called mud drum.
These upper drum and lower drum are connected with two tubes namely down-comer

38
and riser tubes as shown in the figure.Water in the lower drum and in the riser connected
to it, is heated and steam is produced in them which comes to the upper drums naturally.
In the upper drum the steam is separated from water naturally and stored above the
water surface. The colder water is fed from feed water inlet at upper drum and as this
water is heavier than the hotter water of lower drum and that in the riser, the colder
water push the hotter water upwards through the riser. So there is one convectional flow
of water in the boiler system.
Figure 3.27 : Natural water circulation in a water-tube boiler
More and more steam is produced the pressure of the closed system increases which
obstructs this convectional flow of water and hence rate production of steam becomes
slower proportionately. Again if the steam is taken trough steam outlet, the pressure
inside the system falls and consequently the convectional flow of water becomes faster
which result in faster steam production rate. In this way the water tube boiler can control
its own pressure. Hence this type of boiler is referred as self controlled machine.

39
3.9.2 Operation of water tube boiler
Figure 3.28 : Longitudinal drum boile
The water in Babcock and Wilcox boilers pumped by a feed pump and it enters the
drum through the feed check valve up to the prespecified level so that the headers and
tubes are always flooded. When the combustion takes place above the grate, the
products of hot gases come out and rush through each compartment of the combustion
chamber. Hence, the rear part of the tubes has the lowest temperature and the front part
of the tubes as highest temperature. When water is heated inside the tube. Due to
continuous heat supply, some of the water gets vaporized into steam inside the tubes
and a mixture of water and steam enters the boiler drum through the uptake header. The
cold water from the boiler drum comes down through the uptake header and enters the
lower end of the water tubes for getting heated further. This natural circulation is called
thermosiphon system.The steam generated gets collected in the steam space above
water space in the boiler drum. In order to remove all water particles from the steam, it
is finally through the superheating. The superheated steam is then available for use.

40
3.9.3 Types of Water Tube Boiler:
(i). Babcock & Wilcox boiler
(ii). Stirling boiler
(iii). La-Mont boiler
(iv). Benson boiler
(v). Yarrow boiler
(vi). Loeffler boiler
3.9.4 Advantage of Water tube boiler:
 There are many advantages of water tube boiler due to which these types of boiler
are essentially used in large thermal power station.
 Larger heating surface can be achieved by using more numbers of water tubes.
 Due to convectional flow, movement of water is much faster than that of fire
tube boiler, hence rate of heat transfer is high which results into higher
efficiency.
 Very high pressure in order of 140 kg/cm2 can be obtained smoothly.

41
CHAPTER-4
Operation of Steam Boiler

42
4.1 Operation
Boiler operation is very important as safety, efficiency, and a constant supply of steam
or hot water depends on the smooth operation of heating boilers. Boiler operation is a
complicated system, especially the modern boilers that are fully automatic. Any mistake
in operation can cause plant shutdown, and even explosion of the boilers. On the other
hand, a boiler plant can run trouble-free if boilers are operated properly.A boiler
operator or engineer, depending on the size of the boiler, is responsible for its operation.
4.2 Boiler startup & shutdown procedure
4.2.1 Boiler startup
Before going to light up the boiler certain checks shall be done and certain auxiliaries
like CW pumps, ACW pumps, Instrument air compressors, Lube oil systems of various
equipments are to be kept in service. It shall be ensured that all work permits are
returned on the boiler and its related equipment.
 All manhole doors on the boiler and ducts are to be closed.
 All dampers in the flue gas path, primary air path, & secondary air path shall be
checked for their correct position.
 Power supplies for all electrically operated dampers shall be switched on.
 Breakers of all auxiliaries shall be kept in service position.
 D C control supplies shall be ensured for all auxiliaries.
 Local push buttons shall be kept released.
 All breakers shall be selected for remote operation.
 Valves status shall be checked on the boiler.
 Check up the drum level and keep it at (-) level.

43
 Main steam valve at boiler outlet and its bypass valve shall be kept closed.
 Drain valves before main steam stop valve and before ESV shall be kept
opened.
 All super heater vents and drains shall be kept opened.
 All sampling valves shall be kept opened.
 Chemical dosing tank levels both for phosphate and hydrazine shall be checked
and if necessary shall be topped up.
 Condenser hot well level and deaerator levels shall be checked and levels shall
be made up if necessary.
 Boiler seal trough shall be filled with water and seal trough overflow shall be
maintained.
 Before boiler light up the TG set shall be kept on barring gear and the CW
system shall be kept in service.
 Auxiliary cooling water pumps shall be kept in service.
 One boiler feed pump shall be kept in service.
 Fuel oil pump shall be kept in service.
 Fuel oil heating system shall be kept in service and the fuel oil shall be kept
under circulation to raise its temperature.
4.2.1.1 Vacuum pulling
Steam ejector is to be taken into service by supplying steam to the ejector from the
auxiliary steam header at a pressure of 10 kg and 220/240 degrees centigrade. Inlet
steam line drain shall be opened and ejector steam valve is to be opened slowly. After
draining the condensate, the drain valve shall be closed and steam pressure maintained.
Then the condenser air valve shall be opened and vacuum build up observed in the
condense

44
4.2.1.2 Electrical connection
Single phase boilers require voltage/frequency of 220 volt/50hz, 16 amp.Three phase
boilers require voltage/frequency of 380 or 440 volt/50hz, 32 amp The plug should be
inserted at the control panel.And step by step switch on all the plugs of control board.It
will how the green light when it will work well.When it found the yellow light, we have
to realize that, there is something wrong.
Figure 4.1 : Connect the Power of all accessories

45
4.2.1.3 Connecting the oil supply
In preference to a long fuel line (recommended max 3m long), it is more convenient to
use a clean oil container, which must obviously be sited on steady ground (preferably
on a trolley for manoeuvrability).The oil feed pipe from the burner should be connected;
if possible, at least 10 cm from the bottom of the oil barrel, to prevent contamination.
The oil return pipe from the burner (where fitted) can be inserted into the top of the
barrel. These pipes should not be longer than 3 meter. The pipes can be extended (max
5m) if the oil tank is sited on the same level or higher than the boiler.
IMPORTANT - Ensure that the oil pipes have no sharp bends
Figure 4.2 : Open the Gas line main valve
4.2.1.4 Water connection
The boiler should have been supplied with suitable treatment plants according to the
Quality of the local water supply. Having prepared the relevant water softener, the water
should be connected using a water hose with a Geka coupling, directly to the boiler

46
before the filter. Ensure the water supply is coming from a clean source. The emergency
connection should only be used, if the magnetic valve fails during steaming. Connect
the hose from the Dosing Plant, by-passing the valve. The raw water supply hose
remains on its normal position. The water must then be controlled manually and at the
end of the steaming operation, the solenoid must immediately be replaced.
4.2.1.5 Water treatment
Water contains calcium, magnesium, iron, chloride, oxygen, carbonic acid etc in
varying degrees, dependant on the water supply from one area to another, causing boiler
scale and corrosion. Boiler scale primarily consists of chalk, accumulating primarily on
the boiler walls and to some extent can cause complete obstruction of the pipes. This
causes a considerable reduction in heat transfer, thereby drastically reducing the
efficiency of the boiler. Corrosion, unlike scale which builds up in the boiler system,
actually eats into the boiler steel. It is therefore important that the appropriate water
treatment plant is used in conjunction with the boiler:
1. Water hardness up to 15dh (263 ppm) requires only the dosing plant, fitted as
Standard.
2. Water hardness above 15dh (263 ppm) also requires either a single or twin column
ion-exchanger, dependent on the degree of hardness.
4.2.1.6 Testing of steam pressure switch
This switch should be checked daily to ensure it is functioning properly. During the
initial start, make sure the boiler can be tripped off automatically when boiler pressure
attains the cut-off value of the pressure switch. Cut off pressure and differential
pressure can be adjusted with the adjusting screw on top of the switch to suit the
requirement of the factory.

47
4.2.1.7 Testing of flame detector
The detector should be tested weekly to ensure it is in normal working order.An easy
method of testing is by removing the detector head from the boiler and shielding the
sensing head with hand. If boiler trips off automatically, the flame detector is in
satisfactory condition.
4.2.1.8 Steam pressure testing of safety valve
The safe operation of steam boiler depends on the correct functioning of the safety
valve. The safety valve should be lifted daily with the easing gear to prevent sticking of
valve seat and it should be pressure tested weekly as follows:-
(a) Shut off main steam stop valve.
(b) Adjust steam pressure switch to a setting slightly higher than maximum permissible
working pressure.
(c) With boiler on maximum firing rate, observe the pressure gauge. When steam
pressure reaches m.p.w.p., safety valve will automatically open to release steam
pressure. That means safety valve is set correctly and working. Maximum permissible
working pressure can be obtained from the Certificate of Fitness.
(d) If the safety valve does not open when the steam pressure reaches the m.p.w.p.,
boiler should be stopped immediately, and the easing gear operated to release steam and
lower the boiler pressure. Call the Appointed Examiner for examination immediately
4.2.1.9 Switching on Boiler
1. Switch on main ON/OFF switch and the boiler fills automatically. The filling
time is approx 10-20 minutes (depending on the size of the boiler), until the water
is visible in the sight glass.
2.

48
2. When both low water level lights come on, press the re-set button which releases the
locking relays and the boiler is ready for operation.
Figure 4.3 : Switch on Boiler Mountain components
4.2.10 Water level controlling
The water level regulator and limiter control the water feed to the boiler maintaining
the correct levels, indicated by the water level lights (orange). Should the water supply
fail, the boiler will shut down and lock off automatically. The water level limiter is a
safety control which switches the boiler off as soon as the water falls below the lowest
permissible water level.
The water regulator is fitted with 3 electrodes:
 If the water level falls to the lower level, the pump or magnetic valve is switched
on to feed water to the boiler.

49
 When the water level reaches the upper limit, the magnetic valve closes or the
pump is switched off.
 If the water falls to the minimum level, the boiler switches off automatically.
The sight glass will always show the level rising and dropping – however – if the water
moves violently (boiling effect) or foams, then the water quality must immediately be
investigated. The boiler will eventually shut down and probably will have to be emptied
and refilled with fresh water.
Figure 4.4 : Check the Water Level gauge
4.2.1.11 Observations for satisfactory performance of the boiler
 Normal pressure drop between drum and superheater outlet should be 150 to 130
Kg
 Normal pressure drop in the reheater should be 5 to 23.5 Kg
 Flue gas temperature after reheater should be 640 to 660 deg. C
 Flue gas temperatures before economizer should be 420 deg.C
 Flue gas temperature after economizer should be 360 deg. C

50
 Gain in feed water temperature in economizer should be 45 to 50 deg. C .
 Steam temperature before DESH should be less than 456 deg.C
 Reheater spray quantity and burner should be tilt position.
 Feed water temperature before eco. Without HP heaters in service should be
normal.
 Feed water temperature before eco. With HP heaters in service should be To be
normal.
 Flue gas temperatures after air preheaters should be normal.
 Total air flow should be 780 to 840 tons/ hr.
 %O2 in flue gas before air preheater should be 5 to 4.0% .
 Difference in feed flow and feed flow should be normal .
4.2.2 Boiler shut down
When a boiler has to be removed from service for maintenance, inspection, or layup,
the following procedure should be followed:
1. Before shutting the boiler down, give it a good blowdown to remove as much
sediment as possible. Stop when the drain runs clear.
2. Put the boiler steam pressure control in manual mode, and slowly reduce the
firing rate. Watch the main steam header pressure to make sure that the other
boilers are taking up the load. Do not reduce the firing rate below that necessary
to maintain a stable flame.
3. When the boiler is at the minimum firing rate the fuel can be shut off at the main
gas cock. Alternatively, this is often a good time to test the low water level
shutdown switch, or some other boiler interlock. If this method is chosen make
sure you note it in the logbook.

51
4. Allow the fan to post-purge the furnace with a reduced air flow, and then shut
the fan down. Be particularly careful not to let the fan supply large amounts of
cold air into the furnace in the winter.
5. Close the boiler header stop valve.
6. Open a steam drum vent valve when the boiler pressure drops to slightly above
atmospheric pressure. This will prevent a vacuum from forming (not doing this
has resulted in a fatality in recent years, when maintenance personnel proceeded
to open the manhole cover from the water drum of a boiler which had drawn a
vacuum). If the boiler is going to be shut down for an extended period of time it
will need a proper lay-up.
4.3 Boiler Safety Operation
While this section covers many aspects of boiler operation, it does not contain all of the
technical details of boiler design or function. National Board of Boiler Pressure Vessel
inspectors' statistics indicate that boiler and pressure vessel failures result in many
injuries and deaths. In spite of sophisticated mechanical safety devices there is no
substitute for constant vigilance by the Engineer or his/her immediate staff. The most
frequent causes of boiler accidents were noted as deferred repairs and maintenance, and
improper feedwater treatment. It is important for engineers make certain that each
school facility with boilers and pressure vessels is maintained and operated in
accordance with established regulations and the preventive maintenance program.
4.3.1 Boiler Room Doors
As the weather moderate, there is often a tendency to prop open the boiler room door
leading to tunnels, plenums and interior portions of the school facility. In accordance
with Building Codes, the interior boiler room door shall remain closed at all times.
There are no exceptions.

52
4.3.2 safety assurance during Operating the Boiler
As it can be observed, most of the safety issues are linked closely with the boiler
operation. Manual operation of boilers generally leads to overlooking some of the safety
conditions and this might result in a safety hazard. During operation the boiler operator
should flow some things.
Figure 4.5 : Head phone type Ear plug
 Wearing gloves when handling hot items
 Wearing ear plug .
 Wearing the right eye protection and respirators
 Storing rags, oily or dry, in the right containers to prevent spontaneous
combustion due to the heat
 Checking all of the fire safety equipment in the boiler room regularly to make
sure that it works (including sprinklers, fire extinguishers, fire alarms, etc.)
 Never leaving loose tools around or in a pocket where they could slip out
 Never wearing loose clothing that could easily ignite
 Checking all equipment before starting it up for the day

53
4.3.3 Fire Safety Plan
A fire safety plan includes the locations of fire alarms, fire extinguishers, the main
electrical breaker, fire main, and exits for each area of the facility.
Figure 4.6 : Safety Fire Alarm of Boiler room
Figure 4.7 : Fire extinguisher bottle (CO2)
4.3.4 Sources of Fire kept way from the Boiler Room
Boiler rooms are full of combustible materials, making them particularly dangerous. All
fires need a combination of heat, oxygen, and fuel to stay burning. The fuel can be just

54
about anything you can imagine, from fuel oil, to wood, to wallpaper, to loose paper, to
textiles in the room.
4.3.5 Boiler water level
The first duty when taking over a boiler room shift is to make certain the pipe,fittings
and valves between the water glass and boiler are free and open by blowing down the
water column and water glass and noting the promptness of the return of water to the
glass.The most important rule – The most important rule for the safe operation of boilers
is to maintain the proper water-level at all times, and as constant a level as conditions
will permit. If water is not visible in the water glass, shut the boiler off immediately
until a safe water-level has been determined.
4.3.6 Low-water and feedwater controls
The low-water cutoff is the most important electrical/mechanical device on boiler for
maintaining a safe water-level. If a low-water condition develops, it could very well
result in an overheating and explosion of boiler. The low-water cutoff should be tested
at least weekly.
4.3.7 Low-water cut off evaporation
While the boiler is in operation, shut off the feedwater pump and monitor the boiler
water-level. The low-water cut off should shut down the burner before the water level
goes out of sight low; if the burner does not shut off, restart the feedwater pump before
the water level goes out of sight low and immediately troubleshoot the low-water cutoff
to determine the cause of failure. The boiler must be under constant attendance by a
properly licensed engineer at all times during this test.
4.3.8 Low-water cutoff slow drain
While the boiler is in operation, shut off the feedwater pump and slowly open the bottom
blow valve to drain the water from the boiler. The low-water cut off should shut down
the burner before the water level goes out of sight low; if the burner does not shut off,

55
restart the feedwater pump before the water level goes out of sight low and immediately
troubleshoot the low-water cut off to determine the cause of failure. The boiler must
be under constant attendance by a properly licensed engineer at all times during this
4.3.9 Firing
Aside from the standpoint of economy, maintain the fire as uniformly as possible to
avoid an excessive rate of combustion, undesirable variations in temperature and
possible explosions. The destructive force in a boiler explosion is caused by the instant
release of energy stored in the water as heat.
4.3.10 Water gauges
Keep all connections and valves clear. Test by blowing down the water glass and water
column regularly. Gauge cocks or tri-cocks should also be blown regularly.
4.3.11 Safety valves
The safety valve is the most important valve on the boiler. Safety valves prevent
dangerous over pressurization of the boiler. Safety valves are installed in case there is
failure of pressure controls or other devices designed to control the firing rate. All
safety valves should be kept free of debris by testing the safety valve regularly. This
should be done when the steam pressure is at approximately 75 percent of the safety-
valve set pressure. Safety and safety-relief valves on low-pressure boilers should be
tested at least quarterly, this is in accordance with the National Board Inspection Code.
4.3.12 Blow-down valves
The concentration of solids in the boiler should be measured and the boiler blown-
down at such intervals as necessary to maintain established limits. Blow-down valves
are placed at the lowest point of the boiler for the purpose of blowing sediment or scale
from the boiler. They should be maintained in good working order and are to be opened
and closed carefully when used.

56
4.3.13 Starting fires in a boiler
Before starting fires in a cold boiler or restarting a fire that may have been accidentally
extinguished, the entire fireside of the boiler must be thoroughly ventilated (purged)
with the dampers open to remove unburned gases before attempting to relight the fire.
Attempting to start a fire in a boiler with unburned gases is the most common cause of
boiler furnace explosions.
4.3.14 Hot-water systems
These systems are equipped with expansion tanks for the expansion and contraction of
the water as the temperature varies.
4.3.15 Firing cycle, power burners
The burner will start when the aquastat or pressuretrol calls for heat. The breeching
damper will open and the draft fan will purge the combustion chamber. The main gas
or oil valve will be energized when the pilot or ignition is proved.maintenance program
to allow "blow-down" the float chamber at Ieast once a day. Simply open the drain for
3 to 5 seconds making certain that the water drain piping is properly connected to a
discharge line in accordance with City Building Codes. This brief drainage process will
remove loose sediment deposits, and at the same time, test the operation of the water
level control device. If the water level control device does not function properly it must
be inspected, repaired and retested to guarantee proper operation.
4.3.16 Feed Water Pumps
Old, worn and obsolete feed water pumps are sometimes overlooked as potential
problems. A centrifugal pump may have worn seal rings that allow the water to chum
between the suction and discharge openings. An indicator of the latter problem is low
pressure discharge. Also, by comparing the time it takes to raise the boiler water level
to a predetermined level or the time to empty the condensate tank to the time it formerly
required, it is possible to determine if a pump is operating properly. Also, a pump that
operates quietly does not mean it is functioning properly.

57
4.3.17 Overpressure
Safe operation of a boiler is dependent on a vital accessory, the safety valve. Failure to
test the safety valve on a regular basis or to open it manually periodically can result in
heavy accumulations of scale, deposits of sediment or sludge near the valve. These
conditions can cause the safety valve spring to solidify or the disc to seal, ultimately
rendering the safety valve inoperative. A constantly simmering safety valve is a danger
sign and must not be neglected. Your preventive maintenance program includes the
documentation and inspection of the safety valve. A daily test must be performed when
the boiler is in operation Simply raise the hand operating lever quickly to its limit and
allow it to snap closed. Any tendency of a sticking, binding or leaking of the safety
valve must be corrected immediately.
4.3.18 Boiler Storage
As soon as possible after the end of the heating season, take these steps, where
applicable:
1. Remove all fuses from the burner circuit.
2. Remove soot and ash from the furnace, tubes, and flue surfaces.
3. Remove all fly ash from stack cleanout.
4. Drain the broiler completely after letting the water cool.
5. Flush the boiler to remove all sludge, and loose scale particles.
6. See that defective tubes, nipples, stay bolts, packings, and insulation are repaired
or replaced as required.
7. Clean and overhaul all boiler accessories such as safety valves, gauge glasses,
and firing equipment. Special attention should be given to low-water cutoffs and
feedwater regulators to ascertain that float (or electrode) chambers and
connections are free of deposits.
8. Check the condensate return system for tightness of components.

58
4.3.19 Centrifugal Pumps
For a better understanding of the centrifugal pump we must fully understand the
principle of operation. A centrifugal pump is one which depends on centrifugal force
and the rotation of an impeller for its action. The type of pump employed depends on
the service for which it is intended and varies with the capacity required, the variations
in suction and discharge head, the type of water handled (whether hot or cold, clean or
dirty), and the type of the drive to be employed.
Centrifugal pumps may be classified as follows:
1. Volute or turbine, depending on their construction.
2. Single or double-suction, depending on the manner in which the water enters the
pump.
3. Single, double or multistage, depending on the number of stages of impellers in
the pump.
4. It should always be remembered that preventive maintenance of a pump begins
the day the pump is selected. You must remember that full realization of life
expectancy can only be attained through proper implementation of operations. The
following guidelines will assist in attaining these goals:
 Do not overwork your pump. If worked continuously at higher capacities, heads
or speeds than originally specified and installed for, its life will be shortened.
 Provide proper lubrication at all times. Remember that a centrifugal pump
depends on water for lubrication. Keep properly primed when in operation. Use
proper lubricants for bearings.
 Do not allow foot valve screens to become clogged or water supplies to became
less than what is required.
 Do not permit the pump to operate at excessive temperatures.

59
 Do not pump liquids that the pump is not designed for.
 Leave all suction line strainers in place. Rather than remove the strainers, clean
them more frequently.
 Avoid extended periods of cavitation and vibrations or shock.
 Establish a scheduled preventive maintenance program, and keep records.
4.4 Causes of Boiler Failures
Automatic low-high water control equipment must be serviced on a daily basis when
the boiler is in operation. A high frequency of boiler failures is the result of low water,
and can be attributed to a careless boiler operator. A procedure must be established at
regularly clean the glass gauge column by "blowing down" the column at the start
during non-peak operating periods. This ensures ability to determine the level of water
in the boiler. One kind is a failure of the pressure parts of the steam and water sides.
There can be many different causes, such as failure of the safety valve, corrosion of
critical parts of the boiler, or low water level. Corrosion along the edges of lap joints
was a common cause of early boiler explosions.

61
5.1 Definition
The work of keeping something in proper condition, care or upkeep including: taking
steps to avoid something breaking down (preventative maintenance) and bringing
something back to working order is called maintenance .
5.1.2 Different Type of Maintenances
 Planned Maintenance
 Unplanned Maintenance
 Predictive Maintenance
 Preventive Maintenance
 Corrective Maintenance
 Unplanned Maintenance
 Emergency maintenance
 Running Maintenance
 Shutdown Maintenance
 Schedule Maintenance
Figure 5.1 : Types of Maintenances

62
5.1.2.1 Preventive Maintenance
It is a set of activities that are performed on plant equipment, machinery, and systems
before the occurrence of a failure in order to protect them and to prevent or eliminate
any degradation in their operating conditions.
5.1.2.2 Corrective Maintenance
In this type, actions such as repair, replacement, or restore will be carried out after the
occurrence of a failure in order to eliminate the source of this failure or reduce the
frequency of its occurrence.
5.1.2.3 Predictive Maintenance
Predictive maintenance is a set of activities that detect changes in the physical condition
of equipment (signs of failure) in order to carry out the appropriate maintenance work
for maximising the service life of equipment without increasing the risk of failure.
5.1.2.4 Emergency maintenance
It is carried out as fast as possible in order to bring a failed machine or facility to a safe
and operationally efficient condition.
Figure 5.2 : Flow chart o f the Boiler Maintenance

63
5.1.3 Boilers maintenance
All maintenance should be controlled such that replacement parts with the proper rating
are used. Substituting improper materials or parts can result in a boiler explosion or
catastrophic rupture of the steam system.Boilers can be dangerous if not inspected and
maintained properly. Proper maintenance of industrial boilers is critical for ensuring
optimal efficiency and safety of your facility. Because steam boiler problems typically
occur over a long period of time, regular monitoring and maintenance go a long way in
avoiding failures or catastrophic disasters. In the maintenance of boiler is a part of
scheduled maintenance. There are several types of maintenance-
5.1.3.1 Daily Maintenance
1.Check feed water quality.
2.Give blow down at regular intervals ( approx. twice in a shift ).
3.Blow down the Mobrey level switch and gauge glass.
4.Clean the gauge glass externally.
5.Clean the fuel filters and strainers.
6.Drain slightly the oil line bucket filter.
7.Nozzle cleaning.
5.1.3.2 Weekly Maintenance
1.Check the working of low level & extra low level alarm by reducing the water level.
2.Ensure proper lubrication of all moving parts.
3.Clean the flame sensor and viewing glass.
4.Check the conditions of door seals.

64
5.Check that there are no variations in the fuel pressure as compared with that at
commissioning time.
5.1.3.3 Monthly Maintenance
1.Clean electrical contacts of all relays and tighten loose connections if any. Rough
emery paper should not be used for cleaning contacts.
2.Check water pump gaskets and non-return valve.
3.Lubricate the modulation motor linkages.
4.Clean the burner nozzle and ignition electrodes.
5.Check and clean, if necessary, the furnace.
5.1.3.4 Quarterly Maintenance
1.Clean blower fan blades.
2.Drain and clean water service / deaerator tank and fill it with soft / DM water.
3.Clean the fuel filters / strainers.
4.Drain and clean fuel service tank.
5.Open and clean out doors of boiler and super heater. Remove collected soot
deposits.
5.1.3.5 Half Yearly Maintenance
1.Check all valves for leakage; lap them if found leaking.
2.Lubricate bearings of water pumps.
3.Check the sealing of Manhole head holes, and clean out door of smoke box. 4.Clean
the inner and outer face of the sight glass.

practicum report on steam boiler

practicum report on steam boiler

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to practicum report on steam boiler

Similar to practicum report on steam boiler (20)

Recently uploaded

Recently uploaded (20)

practicum report on steam boiler