In this article we will study about what is a boiler? Different types of boiler (steam). The boilers are used in power plants for the generation of steam. They are crucial for the working of a power plant. They are mostly used in the power plants where steam turbines are used for the generation of electricity. The knowledge of boiler is very essential if you are a mechanical engineer.
What is a Boiler?
Working Principle of a Boiler
The boiler works on the same principle as the water is heated in a closed vessel and due to heating, the water changes into steam. This steam steam possesses high pressure kinetic energy.The boiler contains water. The water is heated to its boiling temperature by the use of heat from the furnace. Due to heating of water, it gets converted into high pressure steam. The steam generated is passed through the steam turbines. As the high pressure steam strikes the turbine, it rotates the turbine. A generator is attached to the turbine and the generator also starts to rotate with the turbine and produces electricity.
Different Types of Boiler
1. According to the Contents in the Tubes
(i) Fire Tube Boiler:
- The examples of the fire tube boiler are: simple vertical boiler, Cochran boiler, Lancashire boiler, Cornish boiler, Locomotive boiler, Scotch marine boiler and Velcon boiler.
(ii). Water Tube Boiler:
- The examples of water tube boilers are: La-Mont boiler, Benson boiler, Stirling boiler, Babcock and Wilcox boiler, Yarrow boiler and Loeffler boiler.
2. According to the Number of Tubes
(i). Single Tube Boilers: The boilers which contain one fire tube or water tube are called as single tube boiler.
- The examples of single tube boilers are Cornish boiler and simple vertical boiler.
(ii). Multitubular Boiler: The boilers which has two or more water tube or fire tubes are called multi tubular boilers.
- Lancashire boiler, Locomotive boiler, Cochran boiler, Babcock and Wilcox boilers are multitubular boilers.
3. According to the Position of the Furnace
- Among all the fire tube boilers, most of the boilers are internally fired boilers.
- Water tube boilers are always externally fired boilers.
4. According to the Axis of the Shell
- Examples of vertical boilers are: simple vertical boiler and Cochran boiler.
(ii). Horizontal Boilers: when the axis of the shell in a boiler is found horizontal than it is called as horizontal boiler.
- Lancashire boiler, Babcock and Wilcox boiler and locomotive boilers are examples of horizontal boilers.
5. According to the Methods of Circulation of Water and Steam
- In most of the boilers there is a natural circulation of water such as Lancashire boiler, Cochran boiler etc.
- Forced circulation is used in high pressure boilers such as
La-Mont boiler, Loeffler boiler, Benson boiler etc.
6. According to the use
- These boilers are used in power plants and in industrial
- Locomotive and marine boilers are mobile boilers.