The Lancashire boiler is a horizontal drum axis, natural circulation boiler with two large fire tubes internally. It works by transferring heat from hot flue gases passing through the fire tubes to the surrounding water, converting it to high-pressure steam. It has various components like a manhole, safety valves, and economizers to increase efficiency. Lancashire boilers are commonly used for power generation and in industries due to their high thermal efficiency of 80-90%. While easy to operate and maintain, they have limitations such as low steam pressure production and require more space.

1. Lancashire boiler
Presentated by
engr.. Shakeel Ahmed
BS/RE-26
University of Balochistan Renewable Energy Department

2. What is Lancashire boiler
Working of Lancashire Boiler:
Construction Of Lancashire Boiler:
Boiler mounting
Manhole
Fire door
Ash pit
Economizer
Air preheater
Superheater
Applications of Lancashire Boiler:
Advantages of Lancashire Boiler:
Disadvantages of Lancashire boiler:
Overveiw

3. Lancashire boiler is a horizontal drum axis, natural
circulation, natural draft, two-tubular, low pressure,
stationary, fire tube boiler with furnace located internally.
Its main purpose is to create steam and then this steam is
used to drive steam turbines for power generation. It has
high thermal efficiency and it is about 80 to 90 percent. It
is mostly used in locomotive engines and marines etc
What is Lancashire boiler
The Lancashire Boiler works on the principle of Heat Exchanger. A Heat
Exchanger is a device that is used for the transfer of heat between two
or more fluids.

4. Construction Of Lancashire Boiler:
•Lancashire Boiler consists of a horizontal cylindrical shell filled with water.
This boiler has two large fire tubes that are surrounded by water.
•The cylindrical shell is placed inside a brick wall creates several channels for
the flow of hot flue gases.
•The fire tubes are slightly conical towards its rear end to increase the velocity of
hot flue gases.
•There are dampers at the end of each side channel to regulate the airflow.
•The feed check valve is used to feed water uniformly to the boiler shell.
•An anti priming pipe separates the water from steam which is present at the top
of the boiler.
•A manhole is provided at the top and the bottom of the shell to allow a man to
enter the boiler and clean it.
•A blow off valve is provided to remove the mud that has settled down. It is also
used to empty and clean the boiler.

8. Boiler fuel types

9. Working of Lancashire Boiler:
•At first, water is fed uniformly to the boiler shell using the feed
pump.
•Before entering into the boiler, the water is preheated using the
economizer which gets heat from the flue gases. This economizer
increases the efficiency of the boiler.
•After that, solid fuel is entered from the fire door and burnt on the
grate which is present at the starting if each fire tube.
•As the solid fuel is burnt, flue gases start traveling in the fire tube.
•There is a small brick arc which stops ashes and burnt coal to enter
into the fire tube.
•As the flue gases pass through the fire tubes, these fire tubes start
getting heated and the heat is transferred to the water which is
surrounding the fire tube
•As the heat is transferred to the water, the water starts to get
converting into steam and the steam generated is transferred to the
required place using the stop valve.

10. •Before reaching the stop valve the steam crosses the superheater
which superheats the steam before delivering it to the required
place.
•After passing through the firetube, the flue gases go to the bottom
channel which is created in the brickwork and then the flue gases
pass through the side channel.
•As the flue gases pass through the channels in the brickwork, these
flue gases come in contact with the boiler shell and the boiler shell
gets heated and this heat is transferred to the water inside the boiler
shell and the efficiency of boiler is increased.
•channel and transfer heat to the superheater before passing
through the chimney.
•The flue gases after passing through side channels transfer the
heat to the superheater and then escapes to the environment
through the chimney.
Continue..

11. Working Principle of Lancashire Boiler:
 This Lancashire boiler works on the basic principle of the heat
exchanger.
 It is basically a shell and tube type heat exchanger in which the
gases flow through the tubes and the water flows through a shell.
 The heat is transfer from flue gases to the water through
convection.
 It is a natural circulation boiler that uses the natural current to flow
the water inside the boiler.

12.  Safety valve
 Pressure Gauge
 Feed check valve
 Water Level Indicator
 Blow off valve
 Steam stop valve
 Manhole
 Fire door
 Fusible Plug
 Ash pit
 Damper
 Feed pump
Boiler mounting

13. Safety valve:
The safety valve is used to blow off the steam when the
pressure of the steam inside the boiler exceeds the working pressure.
Pressure gauge:
The function of the pressure gauge is to indicate the
pressure of the steam inside the boiler.
Feed check valve:
It stops and allows the flow of water inside the
boiler.
Water level indicator:
It indicates the level of water in the boiler. It is
placed in front of the boiler. Two water level indicators are used in the
boiler.

14. Blow off Valve:
Its function is to remove the sediments or mud
periodically that is collected at the bottom of the boiler.
 Manhole:
The hole is provided on the boiler so that a man can
enter inside the boiler for the cleaning and repairing purpose.
 Ash pit:
The Ash-pit used to collect the ash of the burnt fuel.
 Feed pump:
It is used to pump the water from storage to the
during the boiler operation.

15.  Steam stop valve:
The function of a steam stop valve is to stop and
the flow of steam from the boiler to the steam pipe.
 Fire door:
This is used to ignite the present fuel inside or outside the
 Fusible plug:
It is used to extinguish the fire inside the boiler when the
level inside the boiler falls to an unsafe level and prevent an explosion.
It also prevents the damage that may happen due to the explosion.
echanical device that abstracts the heat from the flue gases and transfers
to the air(atmosphere).

16. A damper, which is used to control the
draft inside a boiler. ... When hot air from
the boiler rises up the stack, it must be
replaced by cooler air surrounding the
boiler. This cooler air will push the warmer
air up the stack, causing flow.
What is damper

17.  Economizer:
An economizer is a mechanical
that is used as a heat exchanger in the steam
power plant.
It is used to pre-heat the fluid or water by taking
the residual heat from the combustion products(
flue gases).
It is installed to increase the efficiency of the
boiler.
Accessories of Lancashire boiler

18.  Air pre-heater:
It is a mechanical device which abstracts the heat
the flue gases and transfers it to the air. In boilers the pre-heaters
installed in between the economizer and the chimney.
 Super heater:
The main purpose of the super heater is to increase the
temperature of the saturated steam without any change in the
pressure.

19. Applications of Lancashire Boiler:
Lancashire Boiler can be used in several filed like:
The Lancashire boiler is used to drive steam turbines, locomotives,
marines, etc.
It is used in industries like paper industries, textile industries, sugar
industries, tire industries, etc.
Advantages of Lancashire Boiler:
These are some advantages of Lancashire boiler:
This has high thermal efficiency. Thermal efficiency is about 80 to
90%.
This is easy to operate.
It can easily meet the load requirement.
Easy to maintain.
Low consumption of electricity due to natural circulation.

20. Although a Lancashire boiler has some disadvantages and those
are:
 This is a low-pressure type boiler, so high-pressure steam is
not produced.
 It has a limited grate area due to the small diameter of the
tubes.
 The steam production rate is low. It is about 9000 kg/hr.
 Corrosion occurs in the water legs.
 This boiler requires more floor space.
Disadvantages of Lancashire boiler:

21. Thank you