The first type is the bare pipe water wall. This is the simplest structure of the water wall. The advantage is that ordinary seamless steel pipes can be used, and it is more convenient to replace the water wall pipe. The disadvantage is that the temperature of the furnace wall is still high, and heavy refractory bricks are required. The steel frame of the corresponding boiler should be strengthened. , The air leakage of the furnace wall is relatively large. Old-fashioned high-pressure boilers and medium and small boilers are used more frequently.
The second tupe is the membrane water wall. The membrane water wall is welded by seamless steel tubes with fins. The Water Wall Tubes are connected by fins to make the water wall into a whole. This kind of water wall is called a membrane water wall. Its function is to strengthen the heat transfer of the water wall and greatly reduce the temperature of the furnace wall. The furnace wall does not need refractory bricks, but only requires thermal insulation materials. Compared with the conventional heavy furnace wall, the weight can be reduced by 60% ~ 70%, the furnace wall heat storage is reduced by 80%, the start and stop time is shortened, and the fuel consumption is reduced. The load of the furnace steel frame is greatly reduced, saving refractory materials and steel.
The third type is the pierced pipe water wall. The barbed pipe water wall pipe is made by welding many grab nails with a length of 20 to 26 mm and a diameter of 6 to 12 mm on the water wall pipe. It is mainly used to lay the gas belt. Generally, for boilers that burn fuel with low calorific value and low volatile content, in order to stabilize the fire, pierced pipe water walls are often used for laying the fire protection belt.
