Oxygen Sensor Internal Resistance Check: For control instruments equipped with an internal resistance check function for oxygen sensors, perform the check at a gas stable temperature of 850~950°C. Normal range is below 0~25KQ. An abnormal internal resistance can lead to a low carbon potential in the oxygen sensor and an abnormally increased flow rate of enrichment gas.
Oxygen Probe Damage Inspection: After the reference air stops for 1.5 to 2 minutes, read the oxygen probe's electromotive force. After reconnecting the reference air, the reading should not increase by more than 20mv to be considered normal. Oxygen probe damage can cause the oxygen probe to fail to rise and lead to abnormal enrichment gas flow.
Oxygen Sensor Calibration: Regularly perform temperature system validation and correct temperature deviations, and regularly use an infrared gas analyzer such as CO2 to measure or use a carbon film to confirm. Oxygen Sensor Removal and Inspection: Approximately once every three months, remove the oxygen sensor during shutdown for ZrO2 cleaning and inspection; check for bending of the oxygen sensor, and re-install by rotating 180 degrees.
Carbon content sheet preparation: Low carbon steel foil with carbon content below 0.1%, thickness less than 0.003" or below 0.1mm, length approximately 100mm, width about 10mm, weight over 1g, free from rust, discoloration, fine burrs, and other defects. Carbon content sheet cleaning: Clean with a clean cloth or paper towel and dry, ensuring to wipe away any surface debris. Weighing: After cleaning, the carbon content sheet must not be contaminated before weighing. Use a balance or electronic scale with a resolution of 0.1mg to weigh the weight before carbon determination.
Carbon Determination Weighing: Pay attention to selecting the right timing for carbon determination, which should be done during a stage when the temperature and atmosphere are stable. After placing the carbon determination disc, insert it into the furnace, keep it for sufficient time, then remove it to confirm there is no oxidation and clean off any adhering foreign matter. Weigh the weight after the carbon determination.
