Table of Contents
In this article we will discuss fire tube and water tube boiler. Later in the article, we will also differentiate between them.
Fire tube boiler
In fire tube boilers hot gases are present in the tubes. These tubes are further surrounded by water. When heated this water converts into steam. They are considered as low-pressure boilers since; they are used to produce pressures below 25 bar.
Cochran, Cornish, Locomotive, Lancashire, Scotch Marine and Simple vertical boiler are the examples of fire tube boiler.
Water tube boiler
In water tube boiler, water is filled in tubes. These tubes are further surrounded by hot gases. When heated this water converts into steam. They are considered as high-pressure boilers since; they are used to produce pressures above 25 bar.
Benson, Lamont, Loeffler, Yarrow, Babcock and Wilcox boiler are the examples of water tube boiler.
Difference between fire tube and water tube boilers
| Sr. No | Fire tube boiler | Water tube boiler |
| 1 | It is suitable for small power plants | It is suitable for large power plants |
| 2 | It has simple design | It has complex design |
| 3 | They are internally fired | They are externally fired |
| 4 | It can be operated by a relatively less skilled operator | It is operated by a highly skilled operator |
| 5 | It has low operating cost | It has high operating cost |
| 6 | Transportation and installation are difficult | Transportation and installation are relatively easy |
| 7 | Hot gases are present inside tube | Hot gases are present outside tube |
| 8 | Low rate of steam generation | High rate of steam generation |
| 9 | They are less efficient | They have high efficiency |
| 10 | Low rate of steam generation | High rate of steam generation |
| 11 | Risk of explosion is less | Risk of explosion is high |
| 12 | Occupies large space | Occupies less space |
| 13 | They are not suitable for sudden increase in load | They can meet sudden increase in load |
| 14 | Difficult to transport | Relatively easy to transport |
| 15 | Thermal stress in boiler parts is more | Thermal stress in boiler parts is less |
| 16 | Furnace area cannot be easily altered | Furnace area can be easily altered |
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