What is the difference between a fire-tube boiler and a water-tube boiler?

The distinction lies in the design and function of the two types of boilers. In a fire-tube boiler, hot gases generated from combustion pass through tubes that are encased in water. This configuration allows heat from the hot gases to transfer to the water, generating steam. Essentially, the fire-tube design focuses on heating water externally through the combustion gases, making it effective for certain applications.

In contrast, water-tube boilers function differently: they have water circulating within tubes that are surrounded by the hot combustion gases. This design allows water-tube boilers to efficiently heat water and create steam at high pressures, making them suitable for power generation and various industrial applications.

Understanding this fundamental design difference helps clarify why fire-tube boilers and water-tube boilers are utilized in specific scenarios based on their capabilities regarding pressure, efficiency, and maintenance requirements.