Design And Fabrication Of A 14 Inch Diameter Cylindrical Boiler

ABSTRACT

The thermal industry is known as a major source of conventional energy in many countries. Boilers are used in the thermal power plant where chemical energy of the coal is converted into electricity. It is most demanding industry now days because of high energy demand. Boiler is device which is use for power generating by the heating process of water to convert the superheated steam.

This work is aimed at building a cylindrical boiler, 2 m high, has 14inch   diameter which has a hemispherical lid.

This project work is divided into five chapters. Chapter one deals with introductory part of the work.

Chapter two comprises the literature review

Chapter three brings to the methodology

Chapter four highlights about the various design consideration and analysis.

Chapter five discussed on conclusion together with references.

TABLE OF CONTENTS

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

1.0      INTRODUCTION

1.1      Background of the project

1.2      Aim and objectives of the project

1.4      Scope of the Project

1.5      Significance of the Project

1.6      Application and advantages of boilers

1.7      Definitions of Terms

CHAPTER TWO

2.0     LITERATURE REVIEW

2.1   Review of Related Studies

2.2    Classification of Boilers

2.3    Parts of Boilers

CHAPTER THREE

3.0     METHODOLOGY

3.1     Material selection

3.2      Construction for the choice of materials

3.3      Design considerations

3.4      Tools and instruments

3.5      Fabrication process

CHAPTER FOUR

4.1      General Design Consideration

4.2      System Operation

4.3      Design Diagram

4.4      Design Calculation

CHAPTER FIVE

5.1      Conclusion

5.2      References

 

CHAPTER ONE

1.0                                                        INTRODUCTION

1.1                                           BACKGROUND OF THE STUDY

A boiler is an enclosed vessel that provides a means for combustion and transfers heat to water until it becomes hot water or steam. The hot water or steam under pressure is then usable for transferring the heat to a process.

Water is useful and cheap medium for transferring heat to a process. When water is boiled into steam its volume increases about 1,600 times, producing a force that is almost as explosive as gunpowder. This causes the boiler to be extremely dangerous equipment and should be treated carefully.

Liquid when heated up to the gaseous state this process is called evaporation.

The heating surface is any part of the boiler; hot gases of combustion are on one side and water on the other. Any part of the boiler metal that actually contributes to making steam is heating surface. The amount of heating surface of a boiler is expressed in square meters. The larger the heating surface a boiler has, the more efficient it becomes.

The boiler system is made up of:

1. Feed water system
2. Steam system
3. Fuel system

The feed water system provides water to the boiler and regulates it automatically to meet the steam demand. The water supplied to boiler that is converted to steam is called feed water. The sources of feed water are:

1. Condensate or condensed steam returned from the processes
2. Makeup water which is the raw water which must come from outside the boiler room and plant processes.

The steam system collects and controls the steam produced in the boiler. Steam is directed through a piping system to the point of use. Throughout the system, steam pressure is regulated using valves and checked with steam pressure gauges.

The fuel system includes all equipment used to provide fuel to generate the necessary heat. The equipment required in the fuel system depends on the type of fuel used in the system.

Boilers come in different shapes and sizes, but in this work a 14inch diameter of a boiler is designed.

1.2                   AIM AND OBJECTIVES OF THE PROJECT

The main aim of this work is to design and fabricate a 14 inch diameter of a cylindrical boiler. The objectives of the study are:

1. To investigate the design of a cylindrical boiler
2. To design and fabricate a cylindrical boiler

• To carry out an economic analysis of the cylindrical boiler.

1.3                                 SCOPE OF THE PROJECT

The scope of this work involves providing guidance in how to design a boiler thereby increasing the understanding of the basic design of boiler with a suitable size, material and heat of combustion.

The choice of boiler and distributor design is crucial to give the best performance of boiler. Good performance of boiler is influenced by the maximum the heat absorbed and minimum heat loss. The design of boiler may be influenced by factors, including process requirements, economics and safety. All the important parameters use in the guideline are explained in the definition section which help the reader more understand the meaning of the parameters or the term used.

1.4                          SIGNIFICANCE OF THE PROJECT

The theory section explains how to calculate sizing and selection of a boiler. This guideline helps the reader to understand about heat balance concept. The application of the boiler theory with the examples will make the engineer understand boiler fundamentals and then be ready to perform the actual design of the boiler.

1.5             APPLICATION AND ADVANTAGES OF BOILERS

The most common function for any boiler, whether it is an industrial or residential boiler, is to serve as the central heating mechanism for a home, business facility, hospital, commercial complex, etc.

No matter what setting they are used in, boilers operate with the same basic functions and mechanisms that work together to create a contained, heat-generating combustion process.

Boilers draw natural gas from gas lines running through our streets and use this gas to fuel the combustion process for heat creation and distribution throughout a building.

The boiler system relies on a burner to initiate the combustion process, and then heat in the form of steam or hot water moves through the system using pumps, radiators, and heat exchangers.

1.6    DEFINITIONS OF TERMS

Burner – A device for the introduction of fuel and air into a furnace at the desired velocities, turbulence and concentration to establish and maintain proper ignition and combustion of the fuel.

Combustion – The rapid chemical combination of oxygen with the combustible elements of a fuel resulting in the production of heat.

Drum – A cylindrical shell closed at both ends design to withstand internal pressure.

Drum Head – A plate closing the end of a boiler drum or shell.

Dry Steam – Either saturated or superheated steam containing no moisture

 

Economizer – A heat recovery device designed to transfer heat of the products of combustion to boiler feed water.

Excess air – The extra air supplied to the burner beyond the air required for complete combustion. Excess air is supplied to the burner because a boiler firing without sufficient air or “fuel rich” is operating in a potentially dangerous condition.

Fuel – A substance containing combustible matter, and used for generating heat.

Gage Pressure – The pressure above atmospheric pressure.

Gross calorific value (GCV) – The amount of heat liberated by the complete combustion, under specified conditions, by a unit volume of a gas or of a unit mass of a solid or liquid fuel, in the determination of which the water produced by combustion of the fuel is assumed to be completely condensed and its latent and sensible heat made available.

Heat Balance – An accounting of the distribution of the heat input and output.

Lagging – A covering, usually metallic to protect insulating material, on boiler, pipes or ducts.

Leakage – The uncontrolled quantity of fluid which enters or leaves through the enclosure of air or gas passage.

Make-Up – The water added to boiler feed to compensate for that lost through exhaust, blow down, leakage, etc.

Nozzle – A short flanged or welded neck connection on a drum or shell for the outlet or inlet of fluids; also projecting spout for the outlet or inlet of fluids; also a projecting spout through which a fluids flow.

Saturated Steam – Steam at the pressure corresponding to its saturation temperature.

Stack – A vertical conduit to discharge combustion products to the atmosphere.

Steam – The vapor phase of water substantially unmixed with other gases.

Tube – A hollow cylinder for conveying fluids.

Turndown – The ability of the boiler to achieve a wide range (from low to high) of output. The higher the turndown the wider the range of output capabilities.

Wet Steam – Saturated steam which contains moisture