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This is Abhishek, Welcoming you to Engineers Rail- The number one portal for all your engineering queries.
This blog post is going to elaborate on the topic- Types of boilers, in which I will discuss various types of boiler systems based on the various categories.
So, Grab your seat and scroll gently meanwhile I am taking you to the mainstream. Before we proceed, Don’t forget to grab a free PDF of this whole article at the end.
So, Let’s dive in without further delays…
What is a Boiler?
A boiler is a closed vessel shell which used to produce steam by proving the heat source.
The function of a boiler is to either produce hot water or steam.
Classification of boiler-
Different types of boilers are divided into various categories based on their properties and they are-
- Based on the Axis of Drum
- Based on the Position of water and gas
- Based on the location of the furnace
- Based on the working pressure
- Based on the Method of water circulation
- Based on the Mobility of the Boiler
- Based on the Number of tubes
1. Based on the Axis of Drum-
Based on the axis of the drum, a boiler is classified into three types and they are-
- Horizontal Boiler
- Vertical Boiler
- Inclined Boiler
A. Horizontal Boiler-
If a drum of the boiler is placed horizontally or the axis of the boiler drum is horizontal, then this boiler will be known as a horizontal boiler.
An example of a Horizontal Boiler is- Locomotive Boiler
B. Vertical Boiler-
If a drum of the boiler is placed vertically or the axis of the boiler drum is vertical, then this boiler will be known as a vertical boiler.
An example of a Vertical Boiler is- Cochran Boiler
C. Inclined Boiler-
If a drum of the boiler is placed inclined or the axis of the boiler drum is inclined, then this boiler will be known as an inclined boiler.
An example of an Inclined Boiler is- Special Purpose Boiler
2. Based on the Position of water and gas–
Based on the position of water and gas, a boiler is classified into two types and they are-
- Fire tube Boiler
- Water tube Boiler
A. Fire Tube Boiler-
If the hot gases are inside the tubes and water is surrounding the tubes, it will be known as fire tube boiler.
An example of a Fire tube Boiler is- Cornish Boiler
B. Water Tube Boiler-
If the water is inside the tubes and hot gases are surrounded by the tubes, then this type of boiler in mechanical engineering will be known as a water tube boiler.
An example of a Water tube Boiler is- Backcock and Wilcock boiler
3. Based on the Location of the Furnace–
Based on the location of the furnace, a boiler is classified into two types and they are-
- Internally Fired Boiler
- Externally Fired Boiler
A. Internally Fired Boiler-
If the furnace is placed inside of the boiler drum, then it will be known as an internally fired boiler.
An example of an Internally fired Boiler is- Lancashire Boiler
B. Externally Fired Boiler-
If the furnace is placed outside of the boiler drum, then it will be known as an externally fired boiler.
An example of an Externally fired Boiler is- Stirling Boiler
4. Based on the Working Pressure–
Based on the working pressure, a boiler is classified into three types and they are-
- High-Pressure Boiler
- Medium Pressure Boiler
- Low-Pressure Boiler
A. High-Pressure Boiler-
If the pressure of any boiler is more or above than 25bar, then it will be known as a high-pressure boiler.
An example of a high-pressure Boiler is- Velox Boiler
B. Medium-Pressure Boiler-
If the pressure of any boiler ranges between 10 to 25 bar and superheated steam pressure ranges from 2.94 – 4.90 MPa, then it will be known as a Medium-pressure boiler.
An example of a medium-pressure Boiler is- Nestler Boiler
C. Low-Pressure Boiler-
If the pressure of any boiler is below 10 bar, then it will be known as a Low-pressure boiler.
An example of a Low-pressure Boiler is- Locomotive Boiler
5. Based on the Mode of Circulation–
Based on the method of circulation, a boiler is classified into two types and they are-
- Natural Circulation Boiler
- Forced Circulation Boiler
A. Natural Circulation Boiler-
Natural circulation boilers are those boilers which use the temperature differences to circulate the water inside the boiler.
Natural circulation is basically used in sub-critical boilers.
An example of a Force circulation Boiler is- Lancashire Boiler
B. Forced Circulation Boiler-
If the Circulation of water is done through a pump, known as boiler’s Feed Pump, That boiler will be known as a forced circulation boiler because the circulation of water inside the boiler is happening forcefully.
An example of a Force circulation Boiler is- Benson Boiler
6. Based on the Mobility of the Boiler-
Based on the mobility of the boiler, a boiler is classified into two types and they are-
- Stationary Boilers
- Portable Boilers
A. Stationary Boilers-
When a boiler is fixed at its place and can not be moved by any means, in this situation, a boiler is called a stationary boiler.
An example of a Stationary Boiler is- Lancashire Boiler
B. Portable Boilers-
When a boiler can be moved easily from here to there without any agitation with its Boiler’s Mounting and Accessories, then that boiler will be known as a Portable boiler or Mobile Boiler.
An example of a portable boiler is- Scotch Marine Boiler, a Locomotive boiler.
7. Based on the Number of tubes–
Based on the number of tubes, a boiler is classified into two types and they are-
- Single tube Boilers
- Multitube Boilers
A. Single tube Boilers-
If a boiler has a single fire tube or water tube, it will be known as a single-tube boiler.
An example of a single-tube boiler is- Cornish Boiler
B. Multi-tube Boilers-
If a boiler has equipped with multiple fire tubes or water tubes, it will be known as a Multi-tube boiler.
An example of a Multi-tube boiler is- Nestler Boiler
Wrapping Up-
This is all in Types of Boiler. I hope, this blog post served its purpose and gave you what you are here for. If so, share it with near and dear ones and also your social media platforms for maximum reach.
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Abhishek Tiwary is a blogger by passion and a Quality Engineer by profession. He completed his B.Tech degree in the year 2017. Now working in a reputed firm. He loves to share his knowledge with others.