一、Analysis of the Problems Encountered in Long Term Operation of the Flame Detection Outer Tube

1. The flame detection outer duct is installed in the secondary air box of the boiler. Due to the powder carried by the secondary air and prolonged erosion, the hose of the flame detection outer duct is severely worn, resulting in air leakage in the outer duct;
2. The installation of the flame detection outer conduit is too close to the ignition point of the boiler combustion, and the temperature at the front of the burner is too high, causing serious damage to the flame detection optical fiber;
3. The worn metal hose of the flame detection outer conduit cannot effectively protect the optical fiber, leading to frequent replacement of the optical fiber, greatly increasing maintenance costs and workload, and also posing risks to the safe operation of the boiler.

二、Advantages of ceramic conduits
1. Good roundness, smooth glaze, high geometric processing accuracy, and low maintenance costs.
2. Anti erosion, good thermal shock resistance, improved corrosion resistance to molten metal;
3. Ceramics have high temperature resistance, generally reaching over 1000 ℃, meeting the combustion conditions of boilers.
Ceramic conduits also have low thermal conductivity, good thermal stability, resistance to infiltration and corrosion, and are effective in solving problems such as high-temperature burning and wear of external flame detection conduits.

四、升级后达到的效果

1、提高火焰检测器的稳定性；

2、导管的耐磨性、耐温性大幅提升，导管及光纤的寿命均大大延长；

3、维护人员不再需要批量更换导管，维护工作量大幅减少。