What is a flame detector and what is its principle?

Flame detectors are a crucial component in the furnace safety monitoring system, serving to monitor and determine the presence or absence of flames within the furnace. They are an essential part of ensuring the safe and stable operation of boilers.

Fire detection is the "eye" of the boiler, playing a crucial role throughout the entire process from startup to full load operation. In the event of a complete furnace fireout or burner shutdown, the fire detection system emits an alarm signal, triggering a cascade reaction that stops fuel supply to prevent fuel accumulation in the furnace and the occurrence of a boiler explosion.

The detection principle is that the combustion of oil, coal, or gas fuel essentially releases the chemical energy of the fuel in the form of electromagnetic waves. The intermediate products emitted during the combustion of different fuels have different spectral characteristics. The photoelectric sensor within the flame detection probe, upon receiving the emitted spectral radiation of different wavelengths, transmits flame detection signals to the boiler management system or combustion controller through solid-state signal processing technology.

Fuel flame: Contains a significant amount of infrared, some visible light, and a small amount of ultraviolet; Coal dust flame: Contains a small amount of ultraviolet, abundant visible light, and infrared; Gas flame: Rich in ultraviolet, infrared, and less visible light.