The Differences Between Industrial Fire Tube Boiler & Water Tube Boiler

December 17, 2019

difference-industrial-fire-tube-boiler-water-tube-boiler2

Fire Tube Boiler:

The fire tube boiler is a kind of industrial boiler that the flue gas generated after fuel combustion flows through the fire drum or flue pipe to heat the water, steam or steam-water mixture outside the fire drum or flue pipe. It is also called a shell type boiler.
Advantages:
1. It has a simple structure, easy operation, and convenient maintenance.
2. Low requirements for feed water quality.
3. Low failure rate, easy maintenance, and low maintenance cost.
4. The furnace is corrugated and has scalability when thermal expansion occurs.
5. It has a large water capacity, good adaptability to load changes and relatively safe operation.
Disadvantages:
1. There is a large diameter boiler shell, so the metal consumption is large.
2. Boiler capacity and pressure are limited. Generally, the capacity of a fire tube boiler doesn’t exceed 10 t/h and pressure doesn’t exceed 2 MPa.
3. The thermal efficiency is not as high as that of water tube boilers. Large water capacity and slow steam output.
4. Because of the large water capacity, once the boiler breaks down, the damage scope is large and the risk coefficient is relatively high.

Water Tube Boiler:

The water-tube boiler refers to an industrial boiler with a combustion chamber and a heating surface outside the drum, which causes water and steam to flow in the tube.
Advantages:
1. It is composed of small diameter pipes, which can be decomposed and combined, and is easy to deliver.
2. The structure is suitable for high pressure and large capacity boilers, and the performance of the boiler is greatly improved.
3. The heating surface of the water tube boiler is composed of many small pipes. The thermal expansion compensation performance is good and the heating surface can be arranged arbitrarily according to the need. The increase of boiler pressure and capacity is not limited by the boiler drum.

4. Large heat transfer area, better thermal efficiency, save fuel costs.
5. The water capacity is not so much, the steam outputs quickly, and n case of damage, the degree of damage is relatively small.
Disadvantages:
1. The structure is more complex, the volume is larger, the manufacturing cost is higher than that of the fire tube, and the cleaning is more trouble.
2. Boiler’s relative water capacity is small, which requires a higher level of automation control and operation.
3. The influence of scale is quite great and the water quality is strict.
4. Water tubes are easily damaged by long-term contact with high-temperature combustion gases.
5. Low steam dryness and high exhaust temperature.