What is the negative pressure fluctuation of gas heating boiler?
The pressure control of gas heating boiler is called primary loop, and there may be many ways to control the circuit on / off. Like a pressure cooker for cooking, the pressure reaches the set limit, and the pot communicates with the outside world and vents. If you add a pressure sensor to the lid, install an executive element (such as a cylinder) and a processor, then control the lid up and close through the electrical circuit of the latter, and the pot cover to control the pressure in the pot. This is a secondary loop. In pneumatic application, it can be understood that one pneumatic loop can be used to control the control element of another pneumatic loop, so as to achieve the purpose of indirect control. The loop can be understood as the secondary loop.
In the gas-fired heating boiler with balanced ventilation, the negative pressure of the furnace is generally maintained at 20|40 Pa. During normal operation, the negative pressure meter will fluctuate slightly due to the pulsation of combustion. If the fluctuation range of furnace negative pressure is very large, which has an impact on the safety of operation, attention should be paid to finding out the causes and eliminating them in time. The main reasons for the fluctuation of furnace negative pressure are as follows:
1. The swing damper of suction fan or blower regulating damper will swing in a small range in the original position, which is equivalent to the opening and closing, which will affect the air volume, which will cause the negative pressure of the furnace to be unstable.
2. Due to the reasons of powder feeder or pipeline, the amount of fuel entering the furnace fluctuates, and the amount of smoke produced by combustion fluctuates accordingly, which leads to the instability of negative pressure in the furnace.
3. In the process of unstable combustion, due to the change of fuel quality or other reasons, the combustion in the furnace is strong and weak, resulting in negative pressure fluctuation.
4, the influence of soot blowing and coke blowing suddenly has a large amount of steam or air sprayed into the furnace, so that the furnace negative pressure fluctuates, so it is necessary to properly increase the furnace negative pressure in advance when blowing soot. When the large slagging of the furnace suddenly falls, the gas in the furnace will have shock wave due to the impact action, and the flue gas pressure in the furnace will fluctuate greatly, which may cause the gas heating boiler to extinguish the fire.
5. When adjusting the improper load change, it is necessary to adjust the fuel quantity, suction and air supply volume accordingly. If the adjustment operation of gas heating boiler is too fierce, or the adjustment procedure is improper, it will cause the fluctuation of furnace negative pressure.
