BOILERS & IT’S
CLASSIFICATION
For Coal Based Thermal Power Plants
1|Boilers
, 1. BOILER
A boiler is a closed vessel I which the steam is generated from water by applying
heat. The heat or vaporized fluid exits the boiler for use in various processes or heating
applications. A boiler or steam generator is used where a source of steam is needed.
The boilers are mainly used in mobile steam engines such as steam locomotives,
portable engines and steam-powered road vehicles, stationary steam engines,
industrial installations and power stations. The steam generator or boiler is an integral
component of a steam engine when it is used as a prime mover. A boiler includes a
firebox or furnace to burn the fuel and generate heat. The generated heat is
transferred to water to make steam.
1.1 Classifications of Boilers
The steam boilers are classified according to various parameters.
1. According to the flow of water and hot gases
a) Fire tube boiler
If the hot gas is passed through tubes and the water is circulated around tubes,
it is called fire tube boiler.
Examples: Cochran boiler, Lancashire boiler and Locomotive boiler.
b) Water tube boiler
If the water is circulated through a large number of tubes and the hot gases pass
around the tubes, it is called water tube boiler.
Examples: Babcock and Wilcox boiler and Stirling boiler.
2. According to the axis of the shell
a) Vertical boilers
A vertical boiler is a type of fire-tube or water-tube boiler where the boiler
barrel main axis is oriented vertically.
Examples: Vertical boilers are used in steam-powered vehicles and other mobile
machines, including early steam locomotives.
b) Horizontal boilers
A horizontal boiler is a type of fire-tube or water-tube boiler where the boiler
barrel main axis is oriented horizontally.
2|Boilers
CLASSIFICATION
For Coal Based Thermal Power Plants
1|Boilers
, 1. BOILER
A boiler is a closed vessel I which the steam is generated from water by applying
heat. The heat or vaporized fluid exits the boiler for use in various processes or heating
applications. A boiler or steam generator is used where a source of steam is needed.
The boilers are mainly used in mobile steam engines such as steam locomotives,
portable engines and steam-powered road vehicles, stationary steam engines,
industrial installations and power stations. The steam generator or boiler is an integral
component of a steam engine when it is used as a prime mover. A boiler includes a
firebox or furnace to burn the fuel and generate heat. The generated heat is
transferred to water to make steam.
1.1 Classifications of Boilers
The steam boilers are classified according to various parameters.
1. According to the flow of water and hot gases
a) Fire tube boiler
If the hot gas is passed through tubes and the water is circulated around tubes,
it is called fire tube boiler.
Examples: Cochran boiler, Lancashire boiler and Locomotive boiler.
b) Water tube boiler
If the water is circulated through a large number of tubes and the hot gases pass
around the tubes, it is called water tube boiler.
Examples: Babcock and Wilcox boiler and Stirling boiler.
2. According to the axis of the shell
a) Vertical boilers
A vertical boiler is a type of fire-tube or water-tube boiler where the boiler
barrel main axis is oriented vertically.
Examples: Vertical boilers are used in steam-powered vehicles and other mobile
machines, including early steam locomotives.
b) Horizontal boilers
A horizontal boiler is a type of fire-tube or water-tube boiler where the boiler
barrel main axis is oriented horizontally.
2|Boilers
