Correct Answer - Option 2 : Water tube boiler
Explanation:
Fire Tube Boiler: In this boiler, the hot flue gases are present inside the tubes and water surrounds them. They are low-pressure boilers. The operating pressure is about 25 bar.
Example to fire tube boilers:
- Cornish boiler
- Cochran boiler
- Locomotive boiler
- Lancashire boiler
- Scotish marine boiler
Water Tube Boiler: In this boiler, the water is present inside the tubes and the hot flue gases surround them. They are high-pressure boilers and the operating pressure is about 250 bar.
- Stirling boiler
- Babcock and Wilcox boiler
- Yarrow boiler
- Lamont boiler
- Loeffler boiler
