A Seminar On Boiler

INDEX Introduction.

History.

Classification.

Boiler Mountings.

Boilers Accessories.

Important Formulas of Boiler.

Reference.

INTRODUCTIONA boiler is defined as “a closed vessel in which water or other liquid

is heated and steam or vapour is generated”.

As per “The India Boiler Act 1923, a boiler is

a steam generating closed vessel whose minimum

capacity is 22.75 litres”.

In order to generate sream, boiler water is

subjected to heat produced by combustion of fuel

in the boiler furnace.

HISTORY

• In 298-306 AD the Romans built large baths with heated water.

• In 1679 the first boiler with a safety valve was designed by Danis Papin.

• In 1766 John Blakey patented the first water tube boiler.

• In 1804 an American, John Stevens made a boiler with a combination

of small tubes, connected at one end to a reservoir.

• In 1867 two American George Babcock & Stephen Wilcox Created a

water tube boiler name Babcock and Wilcox boiler.

------After that many modern boiler is created.

1) NATURE OF USE-

There are Three types of boiler------

Stationary Boilers-

Babcock & Wilcox Boiler.

Locomotive Boiler-

Traction engines, Steam rollers, Portable engine.

Marine Boiler-

Steam Ships.

2) POSITION OF WATER & FLUE GASES-

There are Two types of boiler------

Water tube Boiler-


Fire tube Boiler-

Cochran Boiler, Lancashire Boiler.

3) AXIS OF BOILER SHELL-


Vertical Boiler-

Cochran Boiler.

Horizontal Boiler-

Lancashire Boiler.

4) POSITION OF FURNACE-


Internally Fired Boiler-

Lancashire Boiler.

Externally Fired Boiler-


5) NATURE OF CIRCULATION-


Free Circulation-

Lancashire Boiler, Cochran Boiler.

Forced Circulation-

Benson Boiler, La Mont Boiler, Loeffler Boiler.

6) NATURE OF FUELS USED-

There are Four types of boiler------

Solid Fuels-


Liquid Fuels-

Volex Boiler.

Gas Fuels-


Nuclear Boiler

7) NO. OF TUBES USED-

There are Two types of boiler-----

Single Tubular Boiler-

Cornish Boiler.

Multitubular Boiler-

Cochran Boiler.

BOILER MOUNTINGS Definition-

Boiler mountings are those mechanical appliances which are

considered essential for operating a boiler smoothly and safely and

which are usually mounted on the surface of a boiler.

1) WATER LEVEL INDICATOR

Function:-

It indicate the water level inside

the boiler vessel. It shows the level in the boiler

drum.

2) FUSIBLE PLUG

Function:-

It is use to protect the

boil against damage due to overheating

caused by low water level in the boiler.

3) MAIN STEAM STOP VALVE

Function:-

It regulate the flow of

steam from boiler to the steam pipe or

from one steam pipe to the other.

4) SAFETY VALVE

Function:-

They guard the

boiler against the excessive high

pressure of steam inside the drum.

If the pressure of steam in the

boiler drum exceeds the working

pressure then the safety valve

allows blow-off the excess quantity

of steam to atmosphere.

5) PRESSURE GAUGE

Function:-

It indicates the pressure of

steam in boiler

6) BLOW OFF COCK

Function:-

The function of blow-off cock is to

discharge mud and other sediments deposited

In the bottom of the water space in the boiler.

When it is open, water under the pressure rushes

out, thus carrying sediments and mud.

7) FEED CHECK VALVE

Function:-

It controls the supply of

water from the boiler when the feed pump

pressure is less than boiler pressure or

pump is stopped.

BOILERS ACCESSORIES Definition-

Boilers Accessories are those appliances which are

installed along with a boiler to improve the operating condition and

overall efficiency of the boiler plant.

1) FEED PUMP

Function:-

The feed pump is a pump

which is used to deliver feed water to

the boiler.

2) INJECTOR

Function:-

Injector is used to feed water

In the boiler. It is commonly employees for

vertical boiler and does not find its

application in large capacity high pressure

boilers . it also uses more space is not space

is not available for the installation for feed

pump.

3) ECONOMISER

Function:-

Economiser increases

the temperature of feed water using

waste of heat to flue gases leaving

the boiler through chimney.

4) SUPER HEATER

Function:-

The function of super

heater is to increase the temperature

of the steam above its saturation

point.

5) STEAM SEPARATOR

Function:-

A Steam separator,

sometimes referred to as a moisture

separator, is a device for separating

water droplets from steam.

6) AIR PREHEATER

Function:-

An air preheater is a

general term to describe any device

designed to heat air before another

process (for example, combustion in

a boiler) with the primary objective of

increasing the thermal efficiency of

the process.

7) STEAM TRAP

Function:-

Steam Trap is

automatically to drain away or

return to the boiler, the water

collected in the steam pipe or

steam jacket due to partial

condensation of steam without

allowing steam escape.

IMPORTANT FORMULAS OF BOILER Finding The Height Of Chimney:-

h=353H

h= Height of water column.

T1= Abs. Temp. of outside air.

H= Height of Chimney.

T= Abs. Temp. of chimney gas.

W= Mass of air required in kg. per kg of fuel

burnt in the boiler furnace

Finding Thermal Efficiency:-

T.E=`

W= Amount of steam produce per hour.

w0= Amount of coal burnt per hour.

h= Total heat of steam.

Cv= Calorific value of coal.

REFERENCE Books:-

Thermal engineering by A.R Basu.

Encyclopedia Britannica.

Internet:-

www.google.co.in

http://en.wikipedia.org/wiki/Boiler

http://www.google.co.in/

http://en.wikipedia.org/wiki/Boiler

Engineering

A Seminar On Boiler