Steam Boiler furnace wall construction standards include four aspects: heat resistance, insulation, sealing, ruggedness.
1. Steam Boiler furnace wall heat resistance:
In some cases, the furnace wall of the Steam Boiler may also have slag attached to it, the temperature of the inner wall of the Steam Boiler furnace wall is usually due to the fact that the Steam Boiler furnace wall is subjected to high temperature radiation of the flame of the combustion chamber or subjected to strong flushing of the high temperature flue gas. Very high, so the Steam Boiler furnace wall should have sufficient temperature performance, and should be able to withstand a lot of temperature changes and resistance to ash erosion ability.
The requirements for the heat resistance of the Steam Boiler to the furnace wall vary depending on the type of Steam Boiler. In a small Steam Boiler, there is a considerable part of the boiler furnace can not lay the water wall tube, the Steam Boiler laying water wall tube where the water wall pipe is usually larger, so the Steam Boiler wall wall temperature of more than 1000 ℃, which requires a good heat resistance of the furnace wall; laying the water pipe wall of the water pipe, depending on the combustion mode and the relative pitch of its inner wall temperature of about 400 ~ 800 ℃; modern Steam Boiler due to the extensive use of dense Or membrane-type water-cooled wall structure, membrane-type ceiling and film-coated heating surface structure, so that the Steam Boiler furnace wall wall can be maintained at a lower temperature level (generally slightly higher than the Steam Boiler operating pressure to see less than the saturation temperature) , So the Steam Boiler wall heat resistance requirements are greatly reduced.
The requirements for heat resistance with the furnace wall are also different depending on the location of the Steam Boiler. In the case of modern Steam Boilers, although the overall temperature of the furnace wall is reduced as previously described, there is still a high temperature in the local furnace wall, such as the burner nozzle, Set the furnace wall, the liquid slag required by the furnace hearth furnace wall, and the door hole wall and so on. All of these parts of the furnace wall together require a higher heat resistance.
2. Steam Boiler furnace wall insulation:
Steam Boiler furnace wall insulation is directly related to the economic operation of the Steam Boiler, Steam Boiler heat balance in the calculation of the heat loss q5 is largely a furnace wall insulation performance of the pros and cons of reflection. Although the value of q5 in high-capacity large-capacity power plant boilers does not seem to be about 10.3%, but its heat flow value is very impressive, furnace wall design and construction should be given high priority.
3. Steam Boiler furnace wall sealing:
The sealing of the furnace wall has a significant effect on the economics of the Steam Boiler operation. As the furnace wall seal caused by the leakage of air, not only will greatly increase the boiler exhaust heat loss, resulting in additional wind power consumption, may also affect the furnace normal combustion process. If the increase in boiler power consumption, then the leakage into the boiler flue air for every 10.% increase in boiler efficiency by about 0.4% to 0.5%. For the positive pressure operation of the boiler, but also requires strict sealing furnace wall to ensure the safety of operational personnel and boiler room environmental health.
The sealing of the Steam Boiler furnace wall can be reflected by the air leakage coefficient △ a, and the value of the air leakage coefficient △ a at different processes is different. For the micro-pressure boiler modern Steam Boiler, △ a = 0 is designed to be done, the Steam Boiler wall sealing is usually sealed by Steam Boiler good design to be guaranteed.
4. Steam Boiler furnace wall of the firmness:
First, the normal operation of the Steam Boiler in the furnace wall on the role of temperature stress, flue gas or atmospheric pressure; Secondly, due to fuel supply or deterioration of combustion conditions, may occur in the Steam Boiler furnace deflagration, resulting in sudden Of the flue gas pressure; again, the furnace burning flame pulsation, may also cause the vibration of the furnace wall; also, in the earthquake area of the furnace wall, also need to bear the earthquake caused by the horizontal wall to produce horizontal inertial force role. Therefore, the Steam Boiler furnace wall should be quite strong to ensure that the role of various external forces in the lower part of the destruction.
In addition to this, often by the slag adhesion and erosion of the Steam Boiler wall, but also requires its sufficient anti-slag performance; circulating fluidized bed Steam Boiler furnace wall, especially the furnace area of the wall, The inner wall of the separator, due to long-term erosion of high concentrations of particles, so the fire or insulation materials should have a good wear resistance; the same time, the Steam Boiler furnace wall should also have a relatively simple structure and low manufacturing And maintenance costs.