Water tube boiler is called water tube boiler, and high temperature flue gas is called fire tube (smoke tube) boiler. Water tube boilers are generally boilers with large evaporation capacity, and the heating surface can be arranged more. Fire tube boilers are generally small boilers, or a mixture of water and fire tubes. The water tube boiler team has relatively high water quality requirements.
The smoke tube boiler is divided into two types, vertical and horizontal. Vertical type can be divided into vertical smoke pipe and horizontal smoke pipe and other models with smaller capacity and better burning of bituminous coal. Horizontal smoke tube boilers are long due to the large number of smoke tubes, and have high rigidity. The interface between the smoke tube and the tube sheet should leak; the distance between the smoke tubes is small, and it is difficult to remove scale. Most of the smoke pipes are arranged horizontally, which is easy to accumulate ash, hinder heat transfer, has large resistance and poor combustion, and is not easy to disassemble, repair, etc., and has now basically withdrawn from the market. Compared with the smoke tube boiler, the water tube boiler does not have an extra large drum in the structure, and the flexible curved water tube replaces the straight smoke tube, which not only saves metal, but also provides conditions for improving capacity and steam parameters, improving combustion conditions and greatly improving thermal efficiency Improved, with good water circulation, maintenance and cleaning, and descaling conditions are better than the smoke tube boiler